Streptococci

Jpn J Ophthalmol, 1999 Sep-Oct, 43(5), 368 - 74
Experimental uveitis induced by intravitreal or intravenous lipoteichoic acid in rabbits; Chen J et al.; PURPOSE: To investigate the role of lipoteichoic acid (LTA), one of the cell wall components in gram-positive bacteria in uveitis . METHODS: Intraocular inflammation in rabbit eyes was induced by intravitreal or intravenous injections of LTA from Staphylococcus aureus or Streptococcus sanguis . The inflammation was monitored progressively with the laser flare-cell photometer, and examined by periodic clinical observations . Histological examinations were performed 24 hours after administration, and aqueous protein concentrations and cell counts were also determined . RESULTS: Intraocular inflammation appeared within 6-9 hours of LTA intravitreal injection . became maximal at about 24-48 hours postinjection, and lasted for nearly 6 days . Intraocular inflammation was also induced by intravenous injection of LTA at a higher dose . Inflammation reached a peak 4-5 hours after injection, and rapidly disappeared in 24 hours . No cellular response was observed in intravenous LTA-treated eyes . CONCLUSIONS: This study demonstrates that LTAs from gram-positive bacteria have the biological activity to induce intraocular inflammation in rabbits by intravitreal or intravenous injection . Therefore, we suggest that LTA may play a role in the pathogenesis of uveitis as one of the etiological factors.

Glycoconj J, 1999 Jan, 16(1), 67 - 71
Determination of the cell adhesion specificity of Streptococcus suis with the complete set of monodeoxy analogues of globotriose; Haataja S et al.; Streptococcus suis causes meningitis and other serious infections in pigs and humans, and binds to host cell globotriosylceramide . In order to determine the essential hydroxyls involved in binding, the complete set of monodeoxy derivatives of the receptor trisaccharide Gal alpha1-Gal beta1-4Glc were tested as inhibitors of bacterial hemagglutination . Removal of the 4''-, 6'', 2' or 3'-hydroxyls abolished inhibitory activity, which indicated that they were critically involved in binding . The same results were obtained using synthetic lipid-linked monodeoxy derivatives of the trisaccharides in a thin-layer overlay assay . The P(N) and P(O) subtypes of the S . suis adhesin showed similar binding patterns . The hydroxyls of the glucose moiety were not critical for binding, although the adhesin binds better to the trisaccharide Gal alpha1-4Gal beta1-4Glc than the disaccharide Gal alpha1-4Gal.

Arch Oral Biol, 1999 Nov, 44(11), 901 - 6
Effects of topical application of free and liposome-encapsulated lactoferrin and lactoperoxidase on oral microbiota and dental caries in rats; Martinez-Gomis J et al.; Four groups of rats were inoculated with Streptococcus sobrinus ATCC 33478 and fed a cariogenic diet for 42 days . Topical treatment with either distilled water, sodium fluoride (0.2%), a solution containing lactoferrin and lactoperoxidase, or a solution containing liposome-encapsulated lactoferrin and liposome-encapsulated lactoperoxidase was applied at intervals for 35 days . Caries incidence in groups treated with liposome-encapsulated lactoferrin and lactoperoxidase was significantly lower than in control groups . The number of viable Strep . sobrinus and the proportion of Strep . sobrinus in the total counts were significantly higher in liposome-treated groups . Free lactoferrin and lactoperoxidase did not cause a significant reduction in caries incidence.

J Microbiol Methods, 1999 Dec, 39(1), 17 - 22
A novel staining method for detecting phytase activity; Bae HD et al.; Differential agar media for the detection of microbial phytase activity use the disappearance of precipitated calcium or sodium phytate as an indication of enzyme activity . When this technique was applied to the study of ruminal bacteria, it became apparent that the method was unable to differentiate between phytase activity and acid production . Strong positive reactions (zones of clearing around microbial colonies) observed for acid producing, anaerobic bacteria, such as Streptococcus bovis, were not corroborated by subsequent quantitative assays . Experimentation revealed that acidic solutions generated false positive results on the selected differential medium . Empirical studies undertaken to find a solution to this limitation determined the false positive results could be eliminated through a two step counterstaining treatment (cobalt chloride and ammonium molybdate/ammonium vanadate) which reprecipitates acid solubilized phytate . This report discusses the application of the developed two step counterstaining treatment for the screening of phytase producing ruminal bacteria as well as its use in phytase zymogram assays.

J Microbiol Methods, 2000 Jan, 39(2), 133 - 43
A sensitive method to detect initiation of growth in Streptococcus gordonii using ribosomal RNA operon-reporter gene fusions; Natarajan A et al.; A system for studying the early growth response of Streptococcus gordonii to environmental stimuli has been developed . A reporter gene, encoding alpha-amylase, has been integrated into an rRNA operon to monitor changes in cellular physiology associated with the initiation of growth . Two such strains with single integrants have been characterized during the transition from lag phase to exponential growth . Synthesis of the reporter is correlated to growth initiation in both strains, and the reporter enzyme is detectable with sufficient sensitivity . Comparison of the expression profiles of the two rrn operons containing the reporter gene suggests that they are differentially expressed over the course of growth.

Int J Pediatr Otorhinolaryngol, 1999 Oct 25, 50(2), 113 - 7
Acute mastoiditis in children--our experience; Vera-Cruz P et al.; The incidence of acute mastoiditis and the number of complications has changed since the 1950s, despite the increasing antibiotic effectiveness . Other series concluded that the incidence of acute mastoiditis is rising in the recent years, which can be justified by the antibiotic resistance of the microorganisms and the absence of paracentesis in the treatment of acute otitis media . Our aim is to approach risk factors, clinical presentation, diagnosis and treatment of acute mastoiditis . We reviewed 62 clinical records of patients in pediatric age, observed in D . Estefania Hospital Lisbon, between January 1993 and December 1997 . There was a relative homogenous distribution during the 5 years of the study period . The patient age ranged from 5 months to 14 years . They all were treated with intravenous antibiotics . The mean duration of treatment was 7.4 days . We registered 15 complications: 14 retroauricular subperiosteal abscesses and one subdural empyema . The most common isolated microorganism was Streptococcus pneumoniae . We found no statistic difference (P > 0.1) in the incidence of acute mastoiditis between the 5 years of the study.

Lab Invest, 1999 Nov, 79(11), 1393 - 401
Rapid appearance of M cells after microbial challenge is restricted at the periphery of the follicle-associated epithelium of Peyer's patch; Borghesi C et al.; M cells within the follicle-associated epithelium (FAE) of the gut play a central role in the initiation of mucosal immune responses by transporting antigens to the intestinal lymphoid tissue . We have previously demonstrated that the instillation into the gut of a nonenteric microorganism, Streptococcus pneumoniae R36a, is an excellent experimental model to investigate the highly dynamic nature of the FAE in response to microbial challenge . In the present study, S . pneumoniae was introduced into rabbit ileal loops, each one containing a Peyer's patch (PP), and the number of M cells was assessed by morphological and functional characteristics in different areas of the FAE after a short time (1-3 hours) . We report that a marked increase in the number of M cells was detected in the periphery, but not in the apical area, of the FAE as early as 1 hour after exposure to S . pneumoniae . Furthermore, a variant of this experiment enabled us to establish that the increased numbers of M cells led to an improved capability of the FAE to transport latex fluorescent microspheres (0.5 microm), highly specific to rabbit M cells, from the gut lumen to the intestinal lymphatic system . In these animals the cisterna chyli was cannulated, and the microparticles were introduced into the intestinal loops after stimulation with pneumococci . The microparticles reaching the lymph were then counted by flow cytometer . We interpreted these results as showing that only enterocytes located within the periphery of the FAE are converted to fully operational M cells by certain microbial interaction and the ability of enterocytes to undergo this conversion may depend on their stage of differentiation.

J Korean Med Sci, 1999 Oct, 14(5), 475 - 9
Evaluation of antibody responses to pneumococcal vaccines with ELISA and opsonophagocytic assay; Kim KH et al.; Antibodies to a capsular polysaccharide (PS) provide protection against Streptococcus pneumoniae which express the homologous capsular serotype, and pneumococcal vaccines are designed to induce antibodies in the capsular PS . Levels and opsonophagocytic capacity of antibodies to the capsular PS of S . pneumoniae serotype 19F were determined by sera from adults immunized with 23-valent S . pneumoniae capsular PS vaccines . Geometric means of IgG anti-19F antibody level and specific opsonic titer rise significantly after immunization . The level of anticapsular PS antibodies for S . pneumoniae 19F serotype is fairly well correlated (r2=O.63) with the opsonophagocytic activities of sera . However, 3.7% (1/27) of serum samples display strikingly less opsonophagocytic activity than expected on the basis of their antibody level . Thus, antibody level may be of general use in predicting vaccine-induced protection among adults for 19F serotype . However, the opsonic activity data suggest that antibody levels are not always indicative of functional antibody.

Scand J Infect Dis, 1999, 31(5), 509 - 10
Toxic-shock-like-syndrome due to Streptococcus pneumoniae sinusitis; Friedstrom SR et al.; We describe a patient with Streptococcus pneumoniae sinusitis associated with a severe sepsis syndrome and desquamative rash whose clinical illness strongly resembled toxic-shock syndrome . Assay of convalescent serum for antibodies to toxic-shock syndrome toxin 1 was negative . This case suggests the possibility of an additional bacterial pathogen associated with toxic-shock syndrome.

Int J Infect Dis, 1999 Summer, 3(4), 211 - 5
Nasopharyngeal carriage of multidrug-resistant Streptococcus pneumoniae in institutionalized HIV-infected and HIV-negative children in northeastern Romania; Leibovitz E et al.; OBJECTIVES: The study compared nasopharyngeal carriage of resistant pneumoniae in human immunodeficiency virus (HIV)-seropositive and -seronegative children . METHODS: Nasopharyngeal colonization with Streptococcus pneumoniae was investigated during May 1996 in 162 HIV-negative infants and children (age range, 1-38 mo) and 40 HIV-infected children (age range, 39-106 mo) living in an orphanage in Iasi, northeastern Romania . The HIV-infected children lived separated from the other children and were cared for by a different staff . Streptococcus pneumoniae was isolated from 12 of 40 (30%) HIV-infected and from 81 of 160 (50%) HIV-negative children . Antimicrobial susceptibility to penicillin and ceftriaxone was determined by E-test, and to another five antibiotics by disk diffusion . Serotyping was performed by the Quellung method on 81 of 93 (87%) isolates . RESULTS: Serotypes 6A, 6B, 19A, and 23F together represented 98% of all isolates . Ninety-nine percent of S . pneumoniae isolates were resistant to penicillin, and 74% were highly resistant to penicillin (minimum inhibitory concentration {MIC} > 1 mg/mL); MIC50 and MIC90 to penicillin of the isolates were 2 mg/mL and 8 mg/mL, respectively . Eighty-nine of ninety-one isolates were susceptible to ceftriaxone; 99%, 87%, 87%, 48%, and 21% of the isolates were resistant to trimethoprim-sulphamethoxazole, erythromycin, clindamycin, tetracycline, and chloramphenicol, respectively . Eighty-two (89%) isolates were multidrug resistant (resistant to =/>3 antibiotic classes); 37 of 92 (40%) isolates were resistant to 5 or more antibiotic classes, and 16 of these 37 (43%) belonged to serotype 19A . All serotype 19 isolates were highly resistant to penicillin . CONCLUSIONS: No significant differences were observed in the resistance rates of S . pneumoniae in HIV-infected children compared to HIV-negative children . Multidrug-resistant pneumococci were highly prevalent in this Romanian orphanage in both HIV-negative and older HIV-infected children . The observed high prevalence of multidrug-resistant pneumococci (coupled with high penicillin resistance) with a limited number of circulating serotypes emphasizes the need to further evaluate the conjugate vaccines in children at risk for invasive pneumococcal infection.

J Biomed Mater Res, 2000 Feb, 49(2), 250 - 6
Adherence of Streptococcus mutans to an E-glass fiber-reinforced composite and conventional restorative materials used in prosthetic dentistry; Tanner J et al.; The adherence of Streptococcus mutans to E-glass used in fiber-reinforced composites, denture base polymer, and four other restoratives was investigated . The materials were studied with and without a parotid saliva and serum pellicle . Specimens of the studied materials (E-glass, denture base polymer, titanium, cobalt-chromium alloy, gold alloy, and grained feldspar ceramic) were incubated in a suspension of S . mutans, allowing initial adhesion to occur . The degree of bacterial adhesion was studied using scanning electron microscopy (SEM) . The studied uncoated materials showed rather similar adhesion of S . mutans . Saliva coating resulted in a decrease of adherence to all materials except glass . With a saliva pellicle E-glass showed the strongest ability to bind S . mutans, and it differed significantly from the other studied materials . Serum coating markedly decreased adhesion to all materials, and only minor differences among the studied materials were observed . The results of this study suggest that the studied restoratives are rather similar with respect to S . mutans adhesion and that a saliva pellicle may promote adhesion of S . mutans to glass fibers .

J Paediatr Child Health, 1999 Oct, 35(5), 466 - 71
Streptococcus pneumoniae antibiotic resistance in Northern Territory children in day care; Skull S et al.; BACKGROUND: There is evidence that the rapid rise in Streptococcus pneumoniae (SP) antimicrobial resistance seen in other countries may have commenced in Australia . Streptococcus pneumoniae carriage and resistance levels are described for urban Northern Territory children in day care . METHODS: A prospective cohort study was conducted of 250 children in nine Darwin day care centres between 24 March and 15 September 1997 . Each fortnight nasopharyngeal swabs were collected from children, and parents were interviewed about medications administered . RESULTS: Streptococcus pneumoniae was detected in 52% (1028/1974) of all nasopharyngeal swabs . Streptococcus pneumoniae was isolated from 92% (231/250) of children at some time . Penicillin resistance was found in 30% (312/1028) of isolates using a screening test . Of these, 256 (82%) had resistance confirmed by E-test . Two hundred and one (20% of all isolates) had intermediate penicillin resistance and 55 (5% of all isolates) had high level resistance . Ceftriaxone resistance was found in 19% of children's first isolates . Resistance to other antibiotics was also common: co-trimoxazole 45%, erythromycin 17%, tetracycline 17% and chloramphenicol 13% . A total of 17% (172/1028) of the isolates were multiresistant . The average fortnightly proportion of children given antibiotics was 16% (405/2476) . CONCLUSION: Levels of intermediate and high level penicillin resistance in this day care population are consistent with previous data from the Northern Territory, and considerably higher than the rest of Australia . The national trend of increasing pencillin resistance is likely to continue.

J Immunol, 1999 Dec 1, 163(11), 6139 - 47
Lipoteichoic acid inhibits lipopolysaccharide-induced adhesion molecule expression and IL-8 release in human lung microvascular endothelial cells; Blease K et al.; Cell adhesion molecule expression (CAM) and IL-8 release in lung microvascular endothelium facilitate neutrophil accumulation in the lung . This study investigated the effects of lipoteichoic acid (LTA), a cell wall component of Gram-positive bacteria, alone and with LPS or TNF-alpha, on CAM expression and IL-8 release in human lung microvascular endothelial cells (HLMVEC) . The concentration-dependent effects of Staphylococcus aureus (S . aureus) LTA (0.3-30 microg/ml) on ICAM-1 and E-selectin expression and IL-8 release were bell shaped . Streptococcus pyogenes (S . pyogenes) LTA had no effect on CAM expression, but caused a concentration-dependent increase in IL-8 release . S . aureus and S . pyogenes LTA (30 microg/ml) abolished LPS-induced CAM expression, and S . aureus LTA reduced LPS-induced IL-8 release . In contrast, the effects of S . aureus LTA with TNF-alpha on CAM expression and IL-8 release were additive . Inhibitory effects of LTA were not due to decreased HLMVEC viability, as assessed by ethidium homodimer-1 uptake . Changes in neutrophil adhesion to HLMVEC paralleled changes in CAM expression . Using RT-PCR to assess mRNA levels, S . aureus LTA (3 microg/ml) caused a protein synthesis-dependent reduction (75%) in LPS-induced IL-8 mRNA and decreased the IL-8 mRNA half-life from >6 h with LPS to approximately 2 h . These results suggest that mechanisms exist to prevent excessive endothelial cell activation in the presence of high concentrations of bacterial products . However, inhibition of HLMVEC CAM expression and IL-8 release ultimately may contribute to decreased neutrophil accumulation, persistence of bacteria in the lung, and increased severity of infection.

Microb Drug Resist, 1999 Fall, 5(3), 219 - 25
Streptococcus pyogenes isolated in Portugal: macrolide resistance phenotypes and correlation with T types . Portuguese Surveillance Group for the Study of Respiratory Pathogens; Melo-Cristino J et al.; From January 1998 to June 1999, 302 clinical isolates of Streptococcus pyogenes were collected from 10 microbiology laboratories in Portugal . All strains were highly sensitive to penicillin (MIC90 = 0.012 mg/liter) . The prevalence of erythromycin resistance was 35.8% and of tetracycline resistance 41.4% . The majority (79.6 %) of erythromycin-resistant strains were of the MLSB constitutive resistance (CR) phenotype with high-level resistance to erythromycin (MIC90 >256 mg/liter) and to clindamycin (MIC90 >256 mg/liter), 16.7% showed the M phenotype with low-level erythromycin-resistance (MIC90 = 24 mg/liter) and susceptibility to clindamycin, and four isolates showed a phenotype characterized by low-level erythromycin resistance (MIC90 = 8 mg/liter) and high-level clindamycin resistance (MIC90 >256 mg/liter), not previously described . Erythromycin resistance was not associated with invasive strains . Only minor discrepancies between disk diffusion and E-test methods were observed . T serotyping was very useful for the epidemiological characterization of the strains . The most prevalent T types were T1, T4, T9, T12, T13, and T28 . A statistically significant association with resistance patterns was found: T12 with erythromycin resistance MLS(B) CR phenotype (p< 0.001), T4 with erythromycin resistance M phenotype (p<0.001), and T13 with tetracycline resistance (p<0.01) . Because of the high prevalence of resistance, careful surveillance of S . pyogenes isolates in Portugal is essential, routine antimicrobial susceptibility testing in clinical microbiology laboratories should be strongly encouraged, antibiotic prescription should be reviewed, and macrolides should no longer be used in the empirical therapy of acute pharyngitis.

Microb Drug Resist, 1999 Fall, 5(3), 215 - 8
Antimicrobial susceptibility of invasive Streptococcus pneumoniae in Italy by agar dilution method and E test; Tarasi A et al.; Few data on antimicrobial susceptibility of invasive Streptococcus pneumoniae isolated in Italy are available . Ninety-two invasive isolates from all over the country collected from January 1997 to April 1998 were tested for sensitivity to penicillin, erythromycin, ceftriaxone, chloramphenicol, tetracycline, and trimethoprim/sulfamethoxazole by the agar dilution method . Five (5.4%) strains were resistant to penicillin (one highly, four intermediately resistant), 8 (8.7%) to chloramphenicol, 27 (29.3%) to erythromycin, 17 (18.5%) to tetracycline (16 highly, one intermediately), and 21 (22.8%) to trimethoprim/sulfamethoxazole (14 highly, 7 intermediately) . All strains were susceptible to ceftriaxone, although the penicillin-resistant strain had the highest minimal inhibitory concentration . (MIC) value (0.5 microg/ml); three penicillin-resistant strains were also resistant to erythromycin . Eight strains were multi-drug resistant, being also resistant to at least three antibiotics . The commercially available E test was compared with the standard agar dilution method for the determination of MIC of penicillin, erythromycin, ceftriaxone, chloramphenicol, and trimethoprim/sulfamethoxazole . E test established the same susceptibility categories for 100% of the strains tested for penicillin and ceftriaxone, 99% for chloramphenicol, 97% for erythromycin, and 74% for trimethoprim/sulfamethoxazole . According to our results, E test was simple to perform, easy to interpret, and a valid method for susceptibility testing of S . pneumoniae . Our study shows that in Italy the rate of penicillin resistance in invasive isolates of S . pneumoniae is one of the lowest in Europe (5.4%), while the rate of erythromycin is very high (29.3%) and is reaching the highest rates of other Southern European countries.

Microb Drug Resist, 1999 Fall, 5(3), 201 - 5
Epidemiological studies on drug resistance in Streptococcus pneumoniae in Hungary: an update for the 1990s; Marton A et al.; The aim of this study was to give an overview about the epidemiological features of pneumococcal resistance in Hungary in the 1990s, and to assess the clinical relevance of drug resistance in Streptococcus pneumoniae primarily in upper respiratory tract infections and the role of risk factors in the acquisition of resistant strains . In Hungary, resistance in S . pneumoniae decreased slightly in recent years, but is still highly prevalent (around 40% to penicillin) compared to the prevalence in western and northern neighboring countries . The prevalent serogroup among resistant strains is 19A, as it was several years ago . In 76 case histories studies, chronic underlying diseases associated with long hospitalization, episodes of earlier hospitalization, and antibiotic therapy were found more frequently if the patient was infected with a resistant strain than with a susceptible one, indicating that these factors promote the acquisition of drug-resistant S . pneumoniae . Resistant S . pneumoniae modified the course of infection by prolonging the duration of hospitalization, making more courses of antibiotics necessary, including parenteral drugs, as well as more invasive interventions such as myringotomy and sinus puncture . These data justify the clinical relevance of resistance, particularly in the upper respiratory tract infections.

Microb Drug Resist, 1999 Fall, 5(3), 183 - 8
Induction of ribosome methylation in MLS-resistant Streptococcus pneumoniae by macrolides and ketolides; Zhong P et al.; One major mechanism for resistance to macrolide antibiotics in Streptococcus pneumoniae is MLS (macrolide, lincosamide, and streptogramin B) resistance, manifested when the 23S rRNA is methylated by the product of an erm gene . This modification results in the decreased binding of all known macrolide, lincosamide, and streptogramin B antibiotics to the ribosome . More than 30 ermAM-containing clinical isolates of S . pneumoniae were examined in our lab and showed high-level resistance (MIC > or =128 microg/ml) to erythromycin, azithromycin, tylosin, clindamycin, and ketolide (macrolides that lack the cladinose sugar) TE-802 . We found that the new generation of ketolides A965 and A088 displayed variable activity against the same group of resistant S . pneumoniae strains . To understand the basis of variability of the minimal inhibitory concentration (MIC) values of A965 and A088, we examined the effects of a series of macrolides and ketolides on the level of 23S rRNA methylation in five ermAM-containing resistant S . pneumoniae isolates . We show here that the basal levels of ribosomal methylation vary from strain to strain . The level of rRNA methylation can be strongly induced by erythromycin, azithromycin, and TE-802, resulting in high-level of resistance to these compounds . Ketolide A965 and A088, however, are weak inducers at sub-MIC drug concentrations, therefore showing variable activities in strains with differential methylation levels.

J Agric Food Chem, 1999 Jan, 47(1), 61 - 6
Productivity and some properties of immunoglobulin specific against Streptococcus mutans serotype c in chicken egg yolk (IgY); Chang HM et al.; Hens were immunized on thighs by using whole cells of Streptococcus mutans MT8148 serotype c strain as antigen through intramuscular (im) and subcutaneous (sc) routes to investigate the difference of immunization reactions and the changes in yolk antibody activities against antigen after initial immunization . Several properties of crude IgY were examined to evaluate the stability during food processing . Results showed that the specificity of IgY of im treated hens was nearly 10 times as high as those of sc treated antibody . IgY from the hens immunized with the serotype c strain showed significant cross-reactions against serotypes e and f, while minor reactions against serotypes a, b, d, and g were observed . In thermal stability tests, IgY activity in both yolk and crude IgY decreased with the increasing temperature, from 70 to 80 degrees C, but the thermal denaturation rates between those two samples were not significantly different . The addition of high levels sucrose, maltose, glycerol, or 2% glycine displayed effective protection against thermal denaturation of IgY . Lyophilized yolk-5% gum arabic powder showed better stability against proteases.

Infect Immun, 1999 Dec, 67(12), 6707 - 9
Role of keratinocyte injury in adherence of Streptococcus pyogenes; Darmstadt GL et al.; Keratinocytes injured acutely by UVB light or lipopolysaccharide were used to test the hypothesis that keratinocyte injury promotes bacterial adherence and the development of group A streptococcal skin infections . Injury did not affect adherence to undifferentiated and differentiated keratinocytes, but keratinocyte differentiation promoted adherence four- to fivefold.

Infect Immun, 1999 Dec, 67(12), 6533 - 42
The pspC gene of Streptococcus pneumoniae encodes a polymorphic protein, PspC, which elicits cross-reactive antibodies to PspA and provides immunity to pneumococcal bacteremia; Brooks-Walter A et al.; PspC is one of three designations for a pneumococcal surface protein whose gene is present in approximately 75% of all Streptococcus pneumoniae strains . Under the name SpsA, the protein has been shown to bind secretory immunoglobulin A (S . Hammerschmidt, S . R . Talay, P . Brandtzaeg, and G . S . Chhatwal, Mol . Microbiol . 25:1113-1124, 1997) . Under the name CbpA, the protein has been shown to interact with human epithelial and endothelial cells (C . Rosenow et al., Mol . Microbiol . 25:819-829, 1997) . The gene is paralogous to the pspA gene in S . pneumoniae and was thus called pspC (A . Brooks-Walter, R . C . Tart, D . E . Briles, and S . K . Hollingshead, Abstracts of the 97th General Meeting of the American Society for Microbiology 1997) . Sequence comparisons of five published and seven new alleles reveal that this gene has a mosaic structure, and modular domains have contributed to gene diversity during evolution . Two major clades exist: clade A alleles are larger and contain an extra module that is shared with many pspA alleles; clade B alleles are smaller and lack this pspA-like domain . All alleles have a proline-rich domain and a choline-binding repeat domain that show 0% divergence from similar domains in the PspA protein . Immunization of a rabbit with a recombinant clade B PspC molecule produced antiserum that cross-reacted with both PspC and PspA from 15 pneumococcal isolates . The cross-reactive antibodies afforded cross-protection in a mouse model system . Mice immunized with PspC were protected against challenge with a strain that expressed PspA but not PspC . The PspA- and PspC-cross-reactive antibodies were directed to the proline-rich domain present in both molecules.

Infect Immun, 1999 Dec, 67(12), 6350 - 7
Group B streptococcal surface proteins as targets for protective antibodies: identification of two novel proteins in strains of serotype V; Areschoug T et al.; Strains of group B streptococcus (GBS) express surface proteins that confer protective immunity . In particular, most strains of the four classical capsular serotypes (Ia, Ib, II, and III) express either of the Rib and alpha proteins, two members of the same protein family . Here, we report a study of surface proteins expressed by strains of serotype V, which has recently emerged as an important serotype among GBS strains causing serious disease . Two novel GBS proteins were identified, purified, and characterized . One of these proteins, designated Fbs, was immunologically unrelated to other GBS surface proteins . This approximately 110-kDa protein was found in 15 of 49 (31%) type V isolates but in few strains of other serotypes . The Fbs proteins expressed by different strains showed limited variation in size . The most common surface protein among type V strains, found in 29 of 49 (59%) isolates, was designated Rib-like, since it cross-reacted with Rib but was not immunologically identical to Rib . Characterization of this Rib-like protein showed that the N-terminal sequence (12 residues) was identical to that of alpha, although these two proteins lacked cross-reactivity . The biochemical and immunological properties of the Rib-like GBS protein indicate that it is closely related to the R28 protein of Streptococcus pyogenes . Importantly, passive and active immunization experiments with mice showed that the Fbs and Rib-like proteins are targets for protective antibodies . These two proteins are therefore of interest for analysis of pathogenic mechanisms and for vaccine development.

Curr Microbiol, 2000 Jan, 40(1), 61 - 6
Sequence analysis of a small cryptic plasmid isolated from Streptococcus suis serotype 2; Takamatsu D et al.; A small cryptic plasmid designated pSSU1 was isolated from Streptococcus suis serotype 2 strain DAT1 . The complete sequence of pSSU1 was 4975 bp and contained six major open reading frames (ORFs) . ORF1 and ORF2 encode for proteins highly homologous to CopG and RepB of the pMV158 family, respectively . ORF5 encodes for a protein highly homologous to Mob of pMV158 . ORF4 encodes for a protein highly homologous to orf3 of pVA380-1 of S . ferus, but its function is unknown . There was no similarity between ORF3 and ORF6 and other protein sequences . In this plasmid, the ORF1 (CopG protein) was preceded by two multiples of direct repeat and the conserved nucleotides that could be the double-strand origin (DSO) of rolling circle replication (RCR) mechanism . The ORF5 (Mob protein) was followed by a potential hairpin loop that could be the single-strand origin (SSO) of RCR mechanism . The sequence, which was complementary to the leader region of Rep mRNA, was homologous to the countertranscribed RNA (ctRNA) of pLS1 . Moreover, a 5-amino acid conserved sequence was found in C terminal of Rep and putative Rep proteins of several pMV158 family plasmids . These observations suggest that this plasmid replicates by use of the rolling circle mechanism.

J Clin Microbiol, 1999 Dec, 37(12), 4198 - 200
Lumbar vertebral osteomyelitis with mycotic abdominal aortic aneurysm caused by highly penicillin-resistant Streptococcus pneumoniae; Naktin J et al.; We present a case of vertebral osteomyelitis with an adjacent abdominal aortic mycotic aneurysm caused by a highly penicillin-resistant Streptococcus pneumoniae strain . The occurrence of all three phenomena in a single patient has not been previously described . This presentation offers the opportunity to reflect on the increasing incidence of S . pneumoniae as a resistant pathogen, the treatment of highly penicillin-resistant S . pneumoniae, and the etiologic agents of both vertebral osteomyelitis and mycotic aneurysm.

J Clin Microbiol, 1999 Dec, 37(12), 4131 - 4
Characteristics of Streptococcus pyogenes serotype M1 and M3 isolates from patients in Japan from 1981 to 1997; Murase T et al.; Streptococcus pyogenes isolates obtained in 1981 to 1997 from patients and healthy subjects were characterized by pulsed-field gel electrophoresis (PFGE) patterns, biotyping, and the presence of spe genes encoding streptococcal pyrogenic exotoxins . Changes in the profiles were shown in the serotype M1/T1 isolates from pharyngitis over this period, but not in serotype M3/T3 isolates . The characteristics of isolates from patients with toxic shock-like syndrome (TSLS) were comparable to those of the other isolates, including those from healthy subjects . This finding suggests that further phenotypic and molecular characterization, such as investigating the genomic difference represented by the pathogenicity island, of isolates with apparently the same profiles would be necessary to determine the etiology of diseases caused by S . pyogenes, including TSLS.

J Clin Microbiol, 1999 Dec, 37(12), 4039 - 41
Genetic relatedness among nontypeable pneumococci implicated in sporadic cases of conjunctivitis; Barker JH et al.; Nontypeable Streptococcus pneumoniae is a common cause of epidemic conjunctivitis . A previous molecular fingerprinting study identified a clone of nontypeable pneumococcus that was responsible for a recent outbreak of conjunctivitis . In the present study, we examined the extent to which pneumococci that cause sporadic cases of conjunctivitis are related to this epidemic strain . Using arbitrarily primed BOX-PCR, we have determined that, of 10 nontypeable pneumococci causing sporadic conjunctivitis, 5 were clonal and closely related to a previous outbreak strain, whereas 5 others were genetically diverse.

J Pharmacol Exp Ther, 1999 Dec, 291(3), 1086 - 92
Streptococcus pneumoniae pneumonia in mice: optimal amoxicillin dosing predicted from a pharmacokinetic-pharmacodynamic model; Moine P et al.; In an attempt to better understand the interaction of amoxicillin with Streptococcus pneumoniae in the lung, and to determine the parameters of therapeutic efficacy of the antimicrobial agent amoxicillin, we used a pharmacokinetic-pharmacodynamic model to describe the overall dose-effect relationship of amoxicillin against 12 strains of S . pneumoniae with penicillin minimum inhibitory concentrations ranging from <0.01 to 16 microg/ml in a neutropenic murine pneumonia model . We were able to correlate amoxicillin dosing, pharmacokinetics, and the temporal changes in bacterial count in lung . Moreover, survival rates measured in one strain at different dosing were significantly related to the number of bacteria in lung calculated from the pharmacokinetic-pharmacodynamic model . Disappearance of amoxicillin from the effect compartment appeared to be very slow and the rate constant (k(e0)) governing this process was significantly different between strains, ranging from 0.00131 to 0.03945 h(-1) . These findings have two major implications: 1) after a single dose of amoxicillin, bacterial counts in lung rapidly decreased and the bacterial growth remained suppressed during a long period of time after cessation of exposure of microorganisms to amoxicillin; and 2) the duration of bacterial growth suppression was related to the intrinsic properties of S . pneumoniae strains rather than to host environment because k(e0) was significantly different between strains . These two premises clearly demonstrate that bacterial growth suppression is related to an in vivo postantibiotic effect . Furthermore, we have shown that the major determinant of amoxicillin in vivo bactericidal activity and therapeutic efficacy appeared to be the dose of amoxicillin because amoxicillin exhibits a rapid dose-dependent killing regardless of the S . pneumoniae strain . Our findings may have implications for the clinical use of amoxicillin . In view of our results, the guidance to increase the amoxicillin-loading dose in pneumococcal pneumonia appears to be immediately clinically relevant.

No To Hattatsu, 1999 Nov, 31(6), 549 - 52
{A case of late onset group B streptococcus meningitis with transient oculomotor nerve palsy}; Murakami K; I report here a case of late onset Group B Streptococcus (GBS) meningitis with transient oculomotor nerve palsy . The boy was admitted to our hospital at 25 days of age . On the 5th hospital day, he was found to be unable to open the left eye . Although light reflex of both the eyes was intact, the left eye was deviated to the left lateral side . We administered intravenously steroid hormone and antibiotics . His eye movements were normalized on the 30th hospital day . Oculomotor nerve palsy in this case may have been caused by vasculitis of the middle cerebral artery . This case shows that steroid hormone is effective for vascular edema complicating neonatal meningitis.

FEMS Microbiol Lett, 1999 Dec 1, 181(1), 113 - 21
Hybridization analysis of the gene encoding a hemolysin (suilysin) of Streptococcus suis type 2: evidence for the absence of the gene in some isolates; Okwumabua O et al.; A hemolysin gene was cloned from a virulent strain of Streptococcus suis type 2 strain 1933 . Analysis of the gene and its product revealed that it is identical to a previously reported hemolysin (suilysin) of S . suis type 2 . Southern hybridization analysis of the digested total genomic DNA from S . suis with the cloned hemolysin DNA sequences as probe indicated that the hemolysin gene is present as a single copy on the genome . Genomic DNA of 63 isolates of S . suis encompassing all known serotypes were examined by DNA hybridization and polymerase chain reaction (PCR) studies for the presence of the hemolysin gene homolog . The results of both techniques were identical and demonstrated the absence of the hemolysin gene in some isolates . In DNA hybridization studies, three DNA probes derived from the hemolysin encoding gene were used . Results showed that sequences encoding the C-terminal 257 amino acid residues (Probe 1) were the most conserved and hybridized to a 1.2 kb fragment in 32 (51%) strains and a 4.0 kb fragment in 23 (36%) strains respectively . Thus, Probe 2 hybridized to the DNA of 55 (87%) of the isolates tested . The first probe (Probe 1) comprising almost the entire hemolysin gene and the third probe (Probe 3) which consisted of the N-terminal sequences hybridized only to a 4.0 kb fragment in 23 (36%) of the strains tested . Eight (13%) of the strains tested were hybridization and PCR negative . The hybridization of the C-terminal end sequences (Probe 2) to the 1.2 kb fragment in 32 (51%) of the strains and the lack of hybridization of the probes to eight (13%) strains may suggest the presence of different types of hemolysin molecule in S . suis strains.

Brain Res, 1999 Nov 13, 847(1), 143 - 8
Hypothermia decreases excitatory neurotransmitter release in bacterial meningitis in rabbits; Irazuzta JE et al.; The excitatory neurotransmitters glutamate (GLU) and aspartate (ASP) are involved in the pathogenesis of neuronal injury in meningitis . Based on past findings that the induction of moderate hypothermia (32-34 degrees C) attenuates the release of GLU in ischemic brain injury, this study was designed to detect if the application of moderate hypothermia decreases the release of excitatory amino acids (EAA) from brain tissue of animals with bacterial meningitis . Also examined was whether meningitis induces the expression of 72-kDa heat shock protein (HSP 70) in the cerebellum and how hypothermia affects it, for induction of HSP 70 has been used as a sensitive marker of neuronal stress in other forms of brain injury . Meningitis was induced by injecting Group B Streptococcus (GBS) into the cisterna magnae of rabbits . Antibiotic treatment began 16 h later . At this time the animals were anesthetized, instrumented, and randomized to normothermic (Nor) or hypothermic (Hy) conditions . Temperatures were strictly regimented for the following 10 h while maintaining stable cardiorespiratory parameters . Cerebrospinal fluid (CSF) samples were then withdrawn to measure concentrations of bacteria, protein, and amino acids . Meningitis causes CSF contents of GLU and ASP to increase significantly . Hypothermia treated animals demonstrated a 40-50% reduction in CSF GLU and ASP . Meningitis induced the expression of HSP 70 in the cerebellum while hypothermic animals experienced a significant decrease HSP 70 induction . These data demonstrate that hypothermia produces an attenuation of the release of excitatory neurotransmitters in meningitis and suggest that this treatment may attenuate neuronal stress.

Int J Antimicrob Agents, 1999 Sep, 13(1), 29 - 33
Prevalence of mefE, erm and tet(M) genes in Streptococcus pneumoniae strains from Central Italy; Latini L et al.; One hundred and seventy-three Streptococcus pneumoniae strains isolated from surveillance studies conducted in daycare centres were studied . The mefE, erm and tet(M) genes were detected in 16.2, 45.1 and 47.4% of isolates respectively . Agreement between PCR results and antibiotic susceptibility patterns was 100% . Macrolide resistance was due to the presence of erm in 73.6% of strains and to the presence of mefE in the remaining 26.4% . All tetracycline resistant strains carried the tet(M) gene . erm was associated with tet(M) in 98.7% of strains, whereas no isolate carrying mefE carried tet(M) . A significant association was found between mefE and serogroup 6 (P < 0.0005) and between erm and tet(M) and serogroup 19 (P < 0.00001).

Pharmazie, 1999 Oct, 54(10), 772 - 5
Antimicrobial activity of selected cyclic dipeptides; Graz M et al.; Cyclic dipeptides are products of rational drug design, which may exhibit both antimicrobial and antitumor properties . The aim of this study was to investigate both the antimicrobial effects of the cyclic dipeptides cyclo(L-phenylalanyl-L-prolyl), cyclo(L-tyrosyl-L-prolyl), cyclo(L-tryptophanyl-L-prolyl) and cyclo(L-tryptophanyl-L-tryptophanyl) and the effects of these cyclic dipeptides on the gastrointestinal epithelium in vitro . Furthermore, a relevant solvent for the possible pharmaceutical application of the products was sought concurrently . The antimicrobial effect of the cyclic dipeptides was assayed using the Kirby-Bauer disc diffusion assay against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis, Streptococcus pneumoniae, Candida albicans, Aspergillus niger and Penicillium notatum . The effect of the cyclic dipeptides on the gastrointestinal epithelium was assessed by changes in alkaline phosphatase expression of HT-29 cells . Cyclo(Pro-Trp) and cyclo(Phe-Pro) show broad spectrum antibacterial properties and cyclo(Trp-Pro) and cyclo(Trp-Trp) show broad spectrum antifungal properties . The maturation of the gastrointestinal cells was enhanced by cyclo(Phe-Pro), cyclo(Tyr-Pro), cyclo(Trp-Trp) and cyclo(Trp-Pro) . The activity of these cyclic dipeptides thus indicates potential application of these compounds as pharmacological agents.

Enferm Infecc Microbiol Clin, 1999 Oct, 17(8), 394 - 7
{Eikenella corrodens: five year experience in a general hospital}; Gasser I et al.; BACKGROUND: Eikenella corrodens is a Gram negative bacillus that colonizes oropharyngeal and digestive mucous membranes . It is difficult to isolate in the laboratory . This might be the reason why its implication in different types of infection is not well known . We report a five year experience in a general hospital . METHODS: Charts of 125 infections have been retrospectively reviewed . No selective medium was employed for the isolation . RESULTS: Infections were related to oral cavity in 68 patients (54%) and to gastrointestinal tract in 45 (36%); in 12 no clear source could be found . The prevailing infections were: postsurgical 32, apendiceal 22, abscesses 22, and traumatic wounds 12 . Seventy two percent of the patients were adults and 93% were hospitalized . Eighteen patients had a neoplasia, 6 were diabetic, and 3 had some kind of immunodeficiency . Etiology was polymicrobial in 91% of the cases, the prevailing association being with Streptococcus spp . (74%) . Only 15 patients had a pure culture, 11 of which had received previous antibiotic treatment . The most serious infections were a subdural empyema secondary to sinusitis, a mediastinitis following a mouth floor abscess, and a peritonitis with pleural empyema preceded by an hepatic abscess . The three were polymicrobial . Outcome was always satisfactory with no associated death . CONCLUSIONS: The origin of these infections is almost always clearly related with its habitat, but their spectrum is wide . Polymicrobial condition of most of them makes diagnosis as well as interpretation of its clinical meaning difficult . Nevertheless, association of E . corrodens with serious or slow healing infections fully justifies the efforts towards its isolation and the choice of antibiotics to which it is susceptible.

J Med Assoc Thai, 1999 Sep, 82(9), 922 - 4
Streptococcus suis meningitis: report of a case; Chotmongkol V et al.; A 50-year-old policeman who presented with subacute meningitis, bilateral rectus muscle palsies, dizziness and early bilateral deafness was reported . Cerebrospinal fluid (CSF) revealed polymorphonuclear pleocytosis with Gram-positive cocci . Blood and CSF cultures grew Streptococcus viridans which subsequently identified to be Streptococcus suis . The patient improved after treatment but deafness persisted.

Mol Microbiol, 1999 Nov, 34(3), 596 - 606
Identification and characterization of a Streptococcus pyogenes ABC transporter with multiple specificity for metal cations; Janulczyk R et al.; Metal ions are crucial trace elements for bacteria infecting the human host . The LraI (lipoprotein receptor-associated antigen I) transporter in Streptococcus spp . belongs to the superfamily of ABC transporters . The transporter consists of a lipoprotein, an ATP-binding protein and a hydrophobic integral membrane protein . Here, we describe a new member of the LraI family in the important human pathogen Streptococcus pyogenes . The system was identified in silico by analysis of the S . pyogenes Genome Sequencing Project . The S . pyogenes operon exhibits an atypical organization compared with equivalents in other Streptococcus spp . The presence and atypical organization of the operon was verified in a number of S . pyogenes strains of different serotypes . Transcriptional analysis of the LraI operon demonstrates a polycistronic transcription attenuated by a stable stem-loop structure, which allows the lipoprotein to be expressed in larger quantities than the other two components . The localization of the native lipoprotein at the bacterial surface was shown by proteolytic digestion of S . pyogenes bacteria and NH2-terminal sequencing of a released lipoprotein fragment . Recombinant lipoprotein was expressed as a GST fusion protein, and studies of molecular interactions with metal radioisotopes demonstrated that the protein has affinity for Zn(II), Fe(III) and Cu(II) . Zn(II) and Cu(II) were found to compete for the same binding site, whereas Fe(III) uses a second site . Also, proton-induced X-ray analysis of lipoprotein samples identified iron, copper and zinc . Finally, a mutant strain lacking a functional mtsABC operon was generated and showed reduced uptake of 55Fe and 65Zn compared with the wild-type strain . The operon encoding this novel ABC transporter with multiple specificity for metal cations is designated mtsABC, for metal transporter of Streptococcus.

Am J Obstet Gynecol, 1999 Nov, 181(5 Pt 1), 1243 - 9
The capture rate of at-risk term newborns for early-onset group B streptococcal sepsis determined by a risk factor approach; Towers CV et al.; OBJECTIVE: Currently, the Centers for Disease Control and Prevention, The American College of Obstetricians and Gynecologists, and the American Academy of Pediatrics recommend that health care providers for pregnant women implement 1 of 2 strategies for the potential prevention of early-onset neonatal group B streptococcal sepsis . Both algorithms recommend intrapartum antibiotic chemoprophylaxis for patients delivered of their neonates at <37 weeks' gestation . The basic difference lies in the management of the term pregnancy . One protocol suggests treatment of all patients with term pregnancies with a positive culture for group B Streptococcus obtained at 35 to 37 weeks' gestation . The second approach recommends treatment on the basis of risk factors of membrane rupture of >/=18 hours' duration or intrapartum temperature of >/=38 degrees C . The capture rate of at-risk neonates determined by the risk factor strategy is quoted as being approximately 70%; however, the basis for this percentage was from studies that used slightly different definitions than the current guidelines and never separated the term from the preterm newborn . Our objective was to prospectively collect every case of blood culture-proven early-onset neonatal group B streptococcal sepsis and determine whether risk factors, as currently defined, were present that might have warranted maternal intrapartum antibiotic chemoprophylaxis . STUDY DESIGN: A prospective study was initiated on July 1, 1987, and completed on December 31, 1996 . Every patient that was delivered of a neonate in whom early-onset group B streptococcal sepsis developed was analyzed in detail for possible intrapartum risk factors . RESULTS: A total of 49 cases of early-onset group B streptococcal sepsis occurred in 46,959 deliveries . Of these 49 newborns, 9 (18%) were delivered at <37 weeks' gestation . The remaining 40 newborns were delivered at term, and only 12 (30%) were delivered with an intrapartum risk factor of either membrane rupture of >/=18 hours' duration or temperature of >/=38 degrees C or both . CONCLUSIONS: On the basis of the data from this study and the current literature, the risk factor approach with the current guideline recommendations would capture <50% of the term newborns in whom sepsis develops.

Am J Obstet Gynecol, 1999 Nov, 181(5 Pt 1), 1197 - 202
Incidence of intrapartum maternal risk factors for identifying neonates at risk for early-onset group B streptococcal sepsis: A prospective study; Towers CV et al.; OBJECTIVE: In mid-1996 and early 1997, the Centers for Disease Control and Prevention, The American College of Obstetricians and Gynecologists, and the American Academy of Pediatrics all published guidelines outlining 2 potential strategies for the purpose of preventing neonatal sepsis caused by group B Streptococcus . One of these approaches involves treating pregnant women intrapartum with antibiotics if any of the following risk factors develop: delivery at <37 weeks' gestation, membrane rupture for >/=18 hours' duration, or temperature during labor of >/=38 degrees C . However, to date there have been no population-based studies that have ascertained the percentage of pregnant women eligible to receive intrapartum antibiotic chemoprophylaxis if these risk factors were used . Our objective was to perform a large patient-based study at >1 institution evaluating all deliveries for the presence of maternal risk factors by using the definitions of the current guidelines . STUDY DESIGN: A prospective cohort study was initiated in 1995 at 3 private community hospitals and 1 private referral center . The study population was composed of 5410 consecutively delivered patients from the 4 different hospitals . Every pregnancy was analyzed for gestational age at delivery, duration of membrane rupture, temperature during labor, and use of intrapartum antibiotic chemoprophylaxis . RESULTS: Of the 5410 patients, a total of 455 (8 . 4%) were delivered of their neonates before 37 weeks' gestation, 421 (7.8%) had rupture of membranes for at least 18 hours' duration, and 378 (7.0%) had an intrapartum temperature of >/=38 degrees C . Overall, 1071 pregnant women (19.8% of the population studied) had >/=1 of the defined risk factors . CONCLUSIONS: These data suggest that, if the current risk factor strategy is used, 19.8% of the delivering population would potentially be candidates for intrapartum antibiotic chemoprophylaxis.

J Bacteriol, 1999 Nov, 181(22), 6914 - 21
Phenotypic consequences resulting from a methionine-to-valine substitution at position 48 in the HPr protein of Streptococcus salivarius; Plamondon P et al.; In gram-positive bacteria, the HPr protein of the phosphoenolpyruvate:sugar phosphotransferase system (PTS) can be phosphorylated on a histidine residue at position 15 (His(15)) by enzyme I (EI) of the PTS and on a serine residue at position 46 (Ser(46)) by an ATP-dependent protein kinase (His approximately P and Ser-P, respectively) . We have isolated from Streptococcus salivarius ATCC 25975, by independent selection from separate cultures, two spontaneous mutants (Ga3.78 and Ga3.14) that possess a missense mutation in ptsH (the gene encoding HPr) replacing the methionine at position 48 by a valine . The mutation did not prevent the phosphorylation of HPr at His(15) by EI nor the phosphorylation at Ser(46) by the ATP-dependent HPr kinase . The levels of HPr(Ser-P) in glucose-grown cells of the parental and mutant Ga3.78 were virtually the same . However, mutant cells growing on glucose produced two- to threefold less HPr(Ser-P)(His approximately P) than the wild-type strain, while the levels of free HPr and HPr(His approximately P) were increased 18- and 3-fold, respectively . The mutants grew as well as the wild-type strain on PTS sugars (glucose, fructose, and mannose) and on the non-PTS sugars lactose and melibiose . However, the growth rate of both mutants on galactose, also a non-PTS sugar, decreased rapidly with time . The M48V substitution had only a minor effect on the repression of alpha-galactosidase, beta-galactosidase, and galactokinase by glucose, but this mutation abolished diauxie by rendering cells unable to prevent the catabolism of a non-PTS sugar (lactose, galactose, and melibiose) when glucose was available . The results suggested that the capacity of the wild-type cells to preferentially metabolize glucose over non-PTS sugars resulted mainly from inhibition of the catabolism of these secondary energy sources via a HPr-dependent mechanism . This mechanism was activated following glucose but not lactose metabolism, and it did not involve HPr(Ser-P) as the only regulatory molecule.

Chest, 1999 Nov, 116(5), 1278 - 81
The impact of blood cultures on antibiotic therapy in pneumococcal pneumonia; Waterer GW et al.; INTRODUCTION: The cost-effectiveness of blood cultures in community-acquired pneumonia (CAP) has been questioned . Although penicillin-resistant Streptococcus pneumoniae is an increasing problem, penicillin therapy, where appropriate, reduces cost and may reduce antibiotic resistance . Blood cultures, however, can only reduce cost if physicians are prepared to alter therapy based on the results . We reviewed our experience to determine how often physicians changed management based on blood culture results positive for S pneumoniae . METHODS: Retrospective chart review was performed of all CAP admissions between January 1996 and December 1998 with blood culture results positive for S pneumoniae . RESULTS: Seventy-four patients out of 1,805 patients admitted with CAP during this period had pneumococcemia . Penicillin resistance was identified in 15 cases (20.3%; high grade in 4 cases) with cephalosporin resistance in 4 of these cases (1 high grade) . Fifty-one patients had initial empiric therapy with a third-generation cephalosporin, and 58 patients had empiric coverage of atypical organisms; no patient received empiric penicillin therapy . Blood culture results altered management in 31 patients (41.9%), but in only 2 cases was this due to antibiotic resistance . Fifty-one patients without penicillin allergy grew penicillin-sensitive pneumococci; only 11 patients (21.6%) were changed to penicillin therapy . Thirteen of 35 patients (37.1%) who were given an additional antibiotic for atypical coverage had this antibiotic ceased . CONCLUSION: Despite evidence of penicillin-sensitive pneumococcal CAP, physicians were reluctant to narrow antibiotic therapy, potentially adding to treatment cost and reducing the impact of blood culture results on management . The impact of penicillin resistance was reduced by the usual empiric choice of a third-generation cephalosporin . While positive blood culture results can clearly be useful in the management of patients with CAP, their cost-effectiveness needs to be assessed in prospective clinical trials.

Chin J Dent Res, 1998 Sep, 1(2), 37 - 40
Reversed-phase high-performance liquid chromatographic measurement of the P-aminobenzoic acid synthesized by Streptococcus sanguis; Zhou XD et al.; OBJECTIVE: This study investigated the biosynthesis of P-aminobenzoic acid by Streptococcus sanguis and the role of P-aminobenzoic acid in the interaction between Streptococcus sanguis and Streptococcus mutans . METHODS: A reversed-phase high-performance liquid chromatographic technique was used to analyze the P-aminobenzoic acid synthesized by Streptococcus sanguis in an anaerobic atmosphere . RESULTS: The results showed, that (1) the chromatographic method established in this study had good linear relation and the average recovery of P-aminobenzoic acid was 80%, and (2) Streptococcus sanguis did synthesize P-aminobenzoic acid, and the mean concentration of P-aminobenzoic acid was 1.23 micrograms/mL . CONCLUSIONS: The results of this study will help further studies of the factors that may have effects on P-aminobenzoic acid synthesis by Streptococcus sanguis and on the role of P-aminobenzoic acid in the microbial homeostasis of dental plaque.

Chin J Dent Res, 1999 Feb, 2(1), 12 - 5
Effects of monoclonal antibody on colonization of Streptococcus sobrinus and development of dental caries in rats; Zhang P et al.; OBJECTIVE: To investigate the effect of local application of monoclonal antibody (McAb) raised against the 210KD cell surface protein antigen (PAg) of Streptococcus sobrinus on the colonization of rats' teeth and the development of dental caries . MATERIALS AND METHODS: Thirty Wistar rats were divided into 3 groups: group 1 received McAb against PAg; group 2 received unrelated mice ascites; group 3 received pure buffered saline . The bacteria were applied 6 times to the occlusal surfaces of molars and to the labial surfaces of incisors . After three applications, streptomycin-resistant S . sobrinus 6715 was applied to the teeth and the rats were fed with caries-inducing diet 2000 . The number of colonized S . sobrinus was counted on the streptomycin-supplemented mutans streptocci agar and expressed as a percentage of the total colonies on BHI agar . The presence of caries was examined and scored following Keyes' procedure . RESULTS: There were significantly lower levels of colonization by S . sobrinus on rats' teeth and lower mean caries scores on the teeth treated with McAb compared with those in the control groups . CONCLUSION: Local passive immunization with McAb against PAg may be an effective way to prevent colonization by implanted S . sobrinus and development of dental caries.

Chin J Dent Res, 1998 Dec, 1(3), 52 - 5
The relationship between caries activity and the status of dental caries--application of the Dentocult SM method; Shi S et al.; OBJECTIVE: To study the relationship between caries activity and the status of dental caries in preschool children using a caries activity test (CAT) . MATERIALS AND METHODS: The status of primary tooth caries in 229 children ages 3 to 5 was examined . Caries incidence, DFT, and caries severity index (CSI) were calculated . Based on the quantity of Streptococcus mutans in the oral cavity detected with Dentocult SM, a caries activity test, four grades of caries activity were classified: Grade 0 (< 10(4) colony-forming units/mL), Grade I (10(4)-10(5) CFU/mL), Grade II (10(5)-10(6) CFU/mL), and Grade III (> 10(6) CFU/mL) . RESULTS: The results showed that 79.48% children had Grade I or higher caries severity . Significant differences of caries activity were found among different grades, which were highly correlated with caries incidence, DFT, and CSI (r = 0.22216, 0.31212, and 0.32276, respectively) . CONCLUSIONS: As a CAT, Dentocult SM is a reliable method for measuring the status of dental caries in preschool children . It is also a valuable tool in the prevention and treatment of dental caries.

Pharmacotherapy, 1999 Nov, 19(11), 1308 - 14
In vitro activity and pharmacodynamics of oral beta-lactam antibiotics against Streptococcus pneumoniae from southeast Missouri; Kays MB et al.; STUDY OBJECTIVES: To determine the frequency of reduced susceptibility to penicillin, and to compare the in vitro activity and pharmacodynamics of oral beta-lactam antibiotics against clinical isolates of Streptococcus pneumoniae from southeast Missouri . SETTING: Cape Girardeau, Missouri (population 35,500) . Interventions . Minimum inhibitory concentrations (MICs) were determined for penicillin, amoxicillin, amoxicillin-clavulanic acid, cefprozil, cefuroxime, cefpodoxime, cefaclor, and loracarbef by E test for 108 isolates of S . pneumoniae . The MIC50, MIC90, and percentage susceptibility were calculated for each agent . Pharmacokinetic variables were obtained from the literature, and serum concentration-time profiles were simulated for a 25-kg child taking pediatric dosages commonly administered to treat otitis media . The average time above MIC (T > MIC) was calculated as percentage of the dosing interval using free concentrations and the MIC for each individual isolate . Analysis of variance (Scheffe post hoc test) was used to determine differences among agents for in vitro activity and T > MIC (level of significance, p<0.05) . MEASUREMENTS AND MAIN RESULTS: The frequency of penicillin-nonsusceptible S . pneumoniae was 28.7% (31/108) . For 25 penicillin-intermediate isolates, amoxicillin and amoxicillin-clavulanic acid were significantly more active than cefprozil, cefaclor, and loracarbef . The T > MIC for amoxicillin and amoxicillin-clavulanic acid, simulated at 13.3 mg/kg every 8 hours, was significantly longer than that for all other beta-lactams . CONCLUSION: Amoxicillin and amoxicillin-clavulanic acid have superior in vitro activity and longer T > MIC for penicillin-intermediate isolates than the other oral beta-lactams.

CLAO J, 1999 Oct, 25(4), 200 - 3
Corneal ulcers and the use of topical fluoroquinolones; Honig MA et al.; PURPOSE: To determine whether the widespread use of topical fluoroquinolones has changed the spectrum of ulcerative keratitis, and to determine how it has affected practice patterns in the treatment of corneal ulcers . METHODS: We retrospectively reviewed the charts of 48 consecutive patients with infectious corneal ulcers from 7/1/91 to 12/31/91 and 47 consecutive patients from 7/1/94 to 12/31/94 . Patients were treated with intensive topical antibiotics (either standard fortified antibiotics or topical fluoroquinolones) at a frequency of at least every hour while awake . Some patients were admitted to the hospital, and some underwent scraping for smears and cultures . RESULTS: Ulcers which were seen in 1994 appear to have been more severe than those seen in 1991 as judged by the presence of more ulcers associated with hypopyons, (P< 0.05) but not with regard to the size of the infiltrate or epithelial defect . More ulcers in 1994 were treated on an outpatient basis (P< 0.02) and fewer ulcers were scraped and cultured than in 1991 (P< 0.001) . Culture results from the 1991 and 1994 groups were similar . The most frequently isolated organisms were coagulase-negative Staphylococcus, Pseudomonas, Staphylococcus aureus, and Streptococcus spp . CONCLUSION: The spectrum of ulcerative keratitis at a tertiary referral center may be showing a trend towards more severe ulcers, but the causative agents responsible for the infection are unchanged.

Arch Otolaryngol Head Neck Surg, 1999 Nov, 125(11), 1262 - 6
Sinogenic subdural empyema and Streptococcus anginosus; Hutchin ME et al.; Subdural empyema (SDE) is most commonly caused by sinusitis and, without early diagnosis and neurosurgical intervention, is associated with high mortality . In a patient with sinusitis who presents with mental status changes, the diagnosis of SDE should be suspected on clinical grounds, even in the absence of significant computed tomographic findings . Computed tomography with contrast is a useful aid in the diagnosis of SDE, but findings may be subtle, and contrasted magnetic resonance imaging is superior . The association of Streptococcus anginosus sinusitis and related intracranial sequelae is important owing to the potentially catastrophic complications and should be recognized by otolaryngologists . In view of the rapidly progressing nature of sinogenic SDE, physicians should strongly consider early institution of aggressive therapy consisting of craniotomy with concurrent sinus drainage in patients in whom sinogenic SDE is suspected on clinical grounds, particularly in the presence of S . anginosus-positive sinus cultures.

New Microbiol, 1999 Oct, 22(4), 383 - 7
Molecular characterization of Streptococcus equi subspecies equi isolated from an Ethiopian camel by ribotyping and PCR-ribotyping; Sechi LA et al.; The aim of this study was to characterize a S . equi subspecies equi strain isolated from an Ethiopian camel by different molecular techniques (Ribotyping and PCR-Ribotyping) . We compared the results obtained with those generated from two strains of the Pasteur Collection . The ribotyping showed the highest power of differentiation, distinguishing between the strains analyzed, whereas PCR-Ribotyping was able only to differentiate the camel isolate but not the strains from the Pasteur Collection . The application of this technique will be very useful to establish a clonal relationship among equine and camelids strains and help the prevention and cure of the equine and camel pathology.

Nippon Jibiinkoka Gakkai Kaiho, 1999 Sep, 102(9), 1036 - 41
{Acute otitis media associated with bone conduction hearing loss}; Ikui A et al.; Eleven patients (12 ears) with acute otitis media associated with raised bone conduction were studied . The patients were from 19 to 70 years old and came to our hospital between November 1996 through May 1997 . Pure tone audiometry revealed mixed hearing loss, but there was no bullous myringitis in all cases . They were treated by oral or intravenous antibiotics, steroids, and myringotomy . Bacteriological examination was done in seven cases, and revealed penicillin resistant Streptococcus pnumoniae in three cases . Complete recovery of hearing loss was obtained in 10 of 12 ears, but sensorineural hearing loss remained in 2 patients . Bacteriological examination and pure tone audiometry in acute otitis media are important for detecting the severity of the disease, determining the administration of steroids, and for the selection of antibiotics.

Oral Microbiol Immunol, 1999 Aug, 14(4), 233 - 7
A DNA probe specific to Streptococcus sobrinus; Ida H et al.; Three DNA fragments (SSB-1, -2 and -3) in the dextranase gene (dex) of Streptococcus sobrinus were amplified by polymerase chain reaction and used as DNA probes . The probes were examined for the specificity and the sensitivity of hybridization with DNA of oral streptococcal species . While probes SSB-1 and SSB-2 were specific to both S . sobrinus and Streptococcus downei, SSB-3 was specific only to S . sobrinus . SSB-3 was able to detect 5 ng of chromosomal DNA purified from S . sobrinus NIDR6715 and DNA extracted from 1 x 10(5) cells of the strain . In addition, SSB-3 could differentiate clinical isolates of S . sobrinus from Streptococcus mutans . These results suggest that SSB-3 is an effective DNA-probe to detect and to identify S . sobrinus.

Oral Microbiol Immunol, 1999 Aug, 14(4), 225 - 32
Physical and genetic map of Streptococcus mutans GS-5 and localization of five rRNA operons; Cappiello MG et al.; The physical map of the 2.1 megabase chromosome of Streptococcus mutans GS-5 has been refined by including all ApaI and SmaI fragments of 5 kbp or greater, and by positioning the fragments generated by the endonuclease I-CeuI . Sixty-three new genetic loci have been added to the map, so that it now contains 90 loci . The new loci include those for 35 cloned streptococcal genes of established function and for 23 S . mutans genes of putative function . In addition, five rrn operons were identified and placed on the map of the chromosome . The presence of a SmaI site in each of the rrn operons allowed the direction of transcription of each operon to be deduced . The orientation of the rrn loci indicates that their transcription is directed away from a small region of the chromosome, identifying a possible region for the initiation of chromosome replication.

Oral Microbiol Immunol, 1999 Aug, 14(4), 213 - 9
The immunogenicity of various peptide antigens inducing cross-reacting antibodies to a cell surface protein antigen of Streptococcus mutans; Kato H et al.; A cell surface protein antigen (PAc) of Streptococcus mutans may be involved in the binding of bacteria to the tooth surface, and has long been focused upon as a candidate for a preventive vaccine of dental caries . Previously the peptide PAc (365-377) was shown to raise an antibody in B10.D2 mice which inhibited the binding of salivary components to the PAc molecule . Using this peptide as a unit peptide, two constructs based on multiple antigenic peptides, and several types of tandem repeats of two or three copies were synthesized to estimate the immunogenicity of these peptides . Increase in the immunogenicity was observed for all constructs with the use of an adjuvant compared to the unit peptide alone . However, the tandem repeat constructs generally induced antibody production in the absence of adjuvant, while the multiple antigenic peptide constructs did not induce antibody production under the same condition . Although such a phenomenon may be restricted to this particular peptide sequence, these results may influence the strategy for the design of peptide vaccines.

Clin Diagn Lab Immunol, 1999 Nov, 6(6), 986 - 8
bca, beta gene, and gene product divergency in reference and prototype strains of streptococcus agalactiae; Maeland JA et al.; Reference and prototype strains of Streptococcus agalactiae (GBS) were originally selected on the basis of phenotypic traits which, however, do not always mirror genotypic traits . A total of 14 reference and prototype GBS strains were examined by PCR designed to detect the bca and beta genes, encoding the c proteins c(alpha) and c(beta), respectively . The cognate proteins were detected by whole-cell-based fluorescent antibody testing and Western blotting . The PCR for beta gene detection and the antibody-based c(beta) protein detection showed concordant results with all of the isolates, whereas 7 of 14 strains which did not express c(alpha) protein at detectable levels contained bca gene elements, consistent with bca gene and gene product divergency in these strains . The results emphasize the importance of genetic characterization of reference and prototype strains of GBS which, in the past, have been selected on the basis of phenotypic traits.

Biochem J, 1999 Nov 15, 344 Pt 1, 259 - 64
Mutation of aspartic acid residues in the fructosyltransferase of Streptococcus salivarius ATCC 25975; Song DD et al.; The site-directed mutated fructosyltransferases (Ftfs) of Streptococcus salivarius ATCC 25975, D312E, D312S, D312N and D312K were all active at 37 degrees C, indicating that Asp-312 present in the 'sucrose box' was not the nucleophilic Asp residue responsible for the formation of a covalent fructosyl-enzyme intermediate required for enzyme activity . Analysis of the kinetic constants of the purified mutated forms of the enzyme showed that Asp-312 was most likely an essential amino acid involved in determining acceptor recognition and/or stabilizing a beta-turn in the protein . In contrast, when the Asp-397 of the Ftf present in the conserved triplet RDP motif of all 60 bacterial and plant family-32 glycosylhydrolases was mutated to a Ser residue, both sucrose hydrolysis and polymerization ceased . Tryptophan emission spectra confirmed that this mutation did not alter protein structure . Comparison of published data from other site-directed mutated enzymes implicated the Asp residue in the RDP motif as the one that may form a transient covalent fructosyl intermediate during the catalysis of sucrose by the Ftf of S . salivarius.

J Mol Biol, 1999 Nov 12, 293(5), 1145 - 60
Studies on the structure and mechanism of a bacterial protein toxin by analytical ultracentrifugation and small-angle neutron scattering; Gilbert RJ et al.; Pneumolysin, an important virulence factor of the human pathogen Streptococcus pneumoniae, is a pore-forming toxin which also possesses the ability to activate the complement system directly . Pneumolysin binds to cholesterol in cell membrane surfaces as a prelude to pore formation, which involves the oligomerization of the protein . Two important aspects of the pore-forming activity of pneumolysin are therefore the effect of the toxin on bilayer membrane structure and the nature of the self-association into oligomers undergone by it . We have used analytical ultracentrifugation (AUC) to investigate oligomerization and small-angle neutron scattering (SANS) to investigate the changes in membrane structure accompanying pore formation.Pneumolysin self-associates in solution to form oligomeric structures apparently similar to those which appear on the membrane coincident with pore formation . It has previously been demonstrated by us using site-specific chemical derivatization of the protein that the self-interaction preceding oligomerization involves its C-terminal domain . The AUC experiments described here involved pneumolysin toxoids harbouring mutations in different domains, and support our previous conclusions that self-interaction via the C-terminal domain leads to oligomerization and that this may be related to the mechanism by which pneumolysin activates the complement system.SANS data at a variety of neutron contrasts were obtained from liposomes used as model cell membranes in the absence of pneumolysin, and following the addition of toxin at a number of concentrations . These experiments were designed to allow visualization of the effect that pneumolysin has on bilayer membrane structure resulting from oligomerization into a pore-forming complex . The structure of the liposomal membrane alone and following addition of pneumolysin was calculated by the fitting of scattering equations directly to the scattering curves . The fitting equations describe scattering from simple three-dimensional scattering volume models for the structures present in the sample, whose dimensions were varied iteratively within the fitting program . The overall trend was a thinning of the liposome surface on toxin attack, which was countered by the formation of localized structures thicker than the liposome bilayer itself, in a manner dependent on pneumolysin concentration . At the neutron contrast match point of the liposomes, pneumolysin oligomers were observed . Inactive toxin appeared to bind to the liposome but not to cause membrane alteration; subsequent activation of pneumolysin in situ brought about changes in liposome structure similar to those seen in the presence of active toxin . We propose that the changes in membrane structure on toxin attack which we have observed are related to the mechanism by which pneumolysin forms pores and provide an important perspective on protein/membrane interactions in general . We discuss these results in the light of published data concerning the interaction of gramicidin with bilayers and the hydrophobic mismatch effect .

Nurse Pract, 1999 Oct, 24(10 Suppl), 1 - 9; quiz 15-6
Acute otitis media: management and surveillance in an era of pneumococcal resistance . Drug-Resistant Streptococcus Pneumoniae Therapeutic Working Group; Dowell SF et al.; Experts in the management of otitis media and the Drug-resistant Streptococcus pneumoniae Therapeutic Working Group were convened by the Centers for Disease Control and Prevention to respond to changes in antimicrobial susceptibility among pneumococci . The objective was to provide consensus recommendations for the management of acute otitis media (AOM) and for the surveillance of drug-resistant Streptococcus pneumoniae . After summarizing published and unpublished data from the scientific literature and the experience of the panel members, the group concluded that oral amoxicillin should remain the first-line antimicrobial agent for treating AOM . For patients with clinically defined treatment failure after 3 days of therapy, useful alternative agents include amoxicillin-clavulanate, cefuroxime axetil, and intramuscular ceftriaxone . The group also made recommendations to improve surveillance and to obtain antimicrobial susceptibility patterns for local geographic areas.

Postepy Hig Med Dosw, 1999, 53(4), 545 - 59
{Molecular mimicry of bacteria as a factor in bacterial pathogenicity}; Witkowska D; Structural and functional homology between bacterial proteins and host antigens, called molecular mimicry, is considered as significant pathogenic factor involved in several autoimmune diseases . The most important examples of this phenomenon reviewed in this work, involve rheumatic fever, Graves' disease, ankylosing spondylitis, Reiter's syndrome and rheumatic arthritis caused by infections with Streptococcus, Yersinia, Klebsiella, Escherichia coli, respectively.

J Nat Prod, 1999 Oct, 62(10), 1379 - 84
Activity of triterpenoid glycosides from the root bark of Mussaenda macrophylla against two oral pathogens; Kim NC et al.; Four new triterpenoid glycosides were isolated from the root bark of Mussaenda macrophylla . Their structures were determined as 3-O-beta-D-glucopyranosyl-28-O-alpha-L-rhamnopyranosyl-16alpha- hydrox y-23-deoxyprotobassic acid (1), 28-O-beta-D-glucopyranosyl-16alpha-hydroxy-23-deoxyprotobassic+ ++ acid (2), 3-O-beta-D-glucopyranosyl-28-O-alpha-L-rhamnopyranosyl-16alpha- hydrox yprotobassic acid (3), and 3-O- inverted question mark{beta-D-glucopyranosyl-(1-->6)}-O-alpha-L-rhamnopyranosyl-(1-->2 )-O-beta-D-glucopyranosyl-(1-->2) inverted question mark-O-beta-D-glucopyranosyl-(1-->3)-O- beta-D-glucopyranosyl-cycloarta-22,24-dien-27-oic acid (mussaendoside W, 4) . Four known triterpenoids {3-O-acetyloleanolic acid (5), 3-O-acetyldaturadiol (6), rotundic acid (7), and 16alpha-hydroxyprotobassic acid (8)} were also isolated . The structures of 1-4 were determined by several spectroscopic techniques including 2D NMR methods . Compounds 1-6 showed inhibitory activity against a periodontopathic bacterium, Porphyromonas gingivalis, but were inactive against the cariogenic organism, Streptococcus mutans.

Antimicrob Agents Chemother, 1999 Nov, 43(11), 2793 - 7
Pharmacokinetics of a once-daily oral dose of moxifloxacin (Bay 12-8039), a new enantiomerically pure 8-methoxy quinolone; Sullivan JT et al.; The pharmacokinetics, safety, and tolerability of oral moxifloxacin, a new 8-methoxy quinolone, were assessed in a randomized, double-blind, placebo-controlled study in which healthy male and female volunteers received either 400 mg of moxifloxacin once daily (n = 10) or a placebo once daily (n = 5) for 10 days . Plasma moxifloxacin concentrations on days 1 and 10 were measured by high-performance liquid chromatography and fluorometric detection . Standard pharmacokinetic parameters were estimated by noncompartmental methods . Natural logarithmic estimates for each pharmacokinetic variable of each subject were analyzed by a two-way analysis of variance . Hematology, blood chemistry, vital signs, and adverse events were monitored, and electrocardiograms (ECG) were performed . Plasma moxifloxacin concentrations of predicted therapeutic relevance were achieved in this study . For day 1, the mean maximum concentration of drug in serum (C(max)) and the area under the concentration-time curve from 0 to 24 h (AUC(0-24)) were 3 . 4 mg/liter and 30.2 mg . h/liter, respectively . Corresponding means on day 10 were 4.5 mg/liter and 48 mg . h/liter, respectively . On day 10, the mean elimination half-life was approximately 12 h . Plasma moxifloxacin concentrations exceeded the MIC for Streptococcus pneumoniae throughout the 24-h dosing period . The day 1 and day 10 mean AUC/MIC ratios were 121 and 192, respectively, and the mean C(max)/MIC ratios were 13 and 18, respectively . Moxifloxacin was well tolerated; no clinically relevant changes in the standard laboratory tests, vital signs, or ECG were observed . Pharmacokinetic parameters demonstrated linearity, and estimates of pharmacokinetic/pharmacodynamic ratios (AUC/MIC and C(max)/MIC) indicate that the regimen of 400-mg once daily should be effective for treating a variety of infections . Moxifloxacin was found to be safe and well tolerated in healthy volunteers when it was given as a single daily 400-mg dose for 10 days.

Antimicrob Agents Chemother, 1999 Nov, 43(11), 2579 - 85
Activities of fluoroquinolones against Streptococcus pneumoniae type II topoisomerases purified as recombinant proteins; Morrissey I et al.; Streptococcus pneumoniae topoisomerase IV and DNA gyrase have been purified from a fluoroquinolone-susceptible Streptococcus pneumoniae strain, from first-step mutants showing low-level resistance to ciprofloxacin, sparfloxacin, levofloxacin, and ofloxacin, and from two clinical isolates showing intermediate- and high-level fluoroquinolone resistance by a gene cloning method that produces recombinant proteins from Escherichia coli . The concentrations of ciprofloxacin, sparfloxacin, levofloxacin, or ofloxacin required to inhibit wild-type topoisomerase IV were 8 to 16 times lower than those required to inhibit wild-type DNA gyrase . Furthermore, low-level resistance to these fluoroquinolones was entirely due to the reduced inhibitory activity of fluoroquinolones against topoisomerase IV . For all the laboratory strains, the 50% inhibitory concentration for topoisomerase IV directly correlated with the MIC . We therefore propose that with S . pneumoniae, ciprofloxacin, sparfloxacin, levofloxacin, and ofloxacin target topoisomerase IV in preference to DNA gyrase . Sitafloxacin, on the other hand, was found to be equipotent against either enzyme . This characteristic is unique for a fluoroquinolone . A reduction in the sensitivities of both topoisomerase IV and DNA gyrase are required, however, to achieve intermediate- or high-level fluoroquinolone resistance in S . pneumoniae.

Microbiology, 1999 Oct, 145 ( Pt 10), 2647 - 53
Repeated extragenic sequences in prokaryotic genomes: a proposal for the origin and dynamics of the RUP element in Streptococcus pneumoniae; Oggioni MR et al.; A survey of all Streptococcus pneumoniae GenBank/EMBL DNA sequence entries and of the public domain sequence (representing more than 90% of the genome) of an S . pneumoniae type 4 strain allowed identification of 108 copies of a 107-bp-long highly repeated intergenic element called RUP (for repeat unit of pneumococcus) . Several features of the element, revealed in this study, led to the proposal that RUP is an insertion sequence (IS)-derivative that could still be mobile . Among these features are: (1) a highly significant homology between the terminal inverted repeats (IRs) of RUPs and of IS630-Spn1, a new putative IS of S . pneumoniae; and (2) insertion at a TA dinucleotide, a characteristic target of several members of the IS630 family . Trans-mobilization of RUP is therefore proposed to be mediated by the transposase of IS630-Spn1 . To account for the observation that RUPs are distributed among four subtypes which exhibit different degrees of sequence homogeneity, a scenario is invoked based on successive stages of RUP mobility and non-mobility, depending on whether an active transposase is present or absent . In the latter situation, an active transposase could be reintroduced into the species through natural transformation . Examination of sequences flanking RUP revealed a preferential association with ISs . It also provided evidence that RUPs promote sequence rearrangements, thereby contributing to genome flexibility . The possibility that RUP preferentially targets transforming DNA of foreign origin and subsequently favours disruption/rearrangement of exogenous sequences is discussed.

Am Heart J, 1999 Nov, 138(5 Pt 2), S534 - 6
Multiple infections in carotid atherosclerotic plaques; Chiu B; BACKGROUND: Chlamydia pneumoniae, cytomegalovirus, herpes simplex virus, and recently, periodontal disease, have been associated with human atherosclerosis . Porphyromonas gingivalis and Streptococcus sanguis are major pathogens associated with periodontitis, a common chronic inflammatory condition in adults . Investigators have found that these infectious agents may influence vascular cell functions by inducing thrombus formation, vascular cell proliferation, apoptosis, and cell death . METHODS AND RESULTS: The main purpose of our study was to investigate the relation between the presence of multiple infectious agents in human carotid endarterectomy specimens and pathoanatomic features of the corresponding carotid plaques . Histologically, plaque rupture of the fibrous cap and communication of the luminal thrombus with the central necrotic lipid core was seen in or at proximity to the macrophage-rich shoulder (unstable plaque region) . Thrombus within the lipid core without plaque rupture was occasionally found near the internal elastic lamina, associated with increased vascularity and lymphocytic infiltrate . Apoptosis, as detected by both the immunohistochemical staining of apoptosis-related proteins and in situ labeling of internucleosomally degraded DNA, was common in atherosclerotic plaques . Immunostainings for C pneumoniae, cytomegalovirus, herpes simplex virus-1, P gingivalis, and S sanguis were positive in the carotid plaques . From 1 to 4 organisms were found in the same specimen . The micro-organisms were immunolocalized in plaque shoulders and lymphohistiocytic infiltrate, associated with ulcer and thrombus formation, and adjacent to areas of strong labeling for apoptotic bodies . CONCLUSIONS: Our data provide evidence that multiple infectious agents may be found in atherosclerotic plaques, and sometimes in the same specimen . The current study is the first to report the detection of 2 major odontopathogens, P gingivalis and S sanguis, in atherosclerotic plaques . The immunolocalization of these micro-organisms within unstable plaque regions and their association with plaque ulceration, thrombosis, and apoptosis in vascular cells are intriguing . Multiple infectious agents may alter vascular cell function and provide a "trigger" for acute ischemic stroke events . Further evidence from human studies and animal models will be needed.

Kansenshogaku Zasshi, 1999 Sep, 73(9), 884 - 92
{Clinical analysis of pneumonia in the elderly in a community hospital--comparison of community-acquired pneumonia and nosocomial pneumonia}; Kobashi Y et al.; We experienced 530 elderly cases with pneumonia among 930 patients with pneumonia in Kawasaki Medical School Kawasaki Hospital between April 1986 and September 1998 . Clinical analysis of all these patients and a comparison of one group consisting of 418 patients with community-acquired pneumonia and another group composed of 112 patients with nosocomial pneumonia were performed . In all of the elderly patients with pneumonia, respiratory symptoms and inflammatory findings were less frequent, but were frequent for those in poor general and nutritional condition . The causative microorganism was isolated in 42% of these patients . Streptococcus pneumoniae, MSSA and Klebsiella pneumoniae were frequently isolated from the sputum of the patients with community-acquired pneumonia, while Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Methicillin-sensitive Staphylococcus aureus (MSSA) were frequently isolated from that of nosocomial pneumonia patients . Mycoplasma pneumoniae, Chlamydia pneumoniae and some viruses were less frequent for patients in both groups . Although many intravenous antibiotics, such as cephem or carbapenem were administered to patients in both groups, the prognosis was relatively good for those with community acquired pneumonia but was extremely poor for those with nosocomial pneumonia despite mechanical ventilation or steroid pulse therapy for many patients.

Neurology, 1999 Oct 22, 53(7), 1584 - 7
Clinical outcome in pneumococcal meningitis correlates with CSF lipoteichoic acid concentrations; Schneider O et al.; Lipoteichoic and teichoic acids are components of the cell wall of Streptococcus pneumoniae . A recently developed enzyme immunoassay was used in patients with pneumococcal meningitis to investigate lipoteichoic and teichoic acid concentrations in CSF at the first lumbar puncture in relation to the clinical outcome determined by the Glasgow Outcome Scale . Lipoteichoic and teichoic acid concentrations in CSF were significantly associated with neurologic sequelae and mortality in S . pneumoniae meningitis.

Can J Vet Res, 1999 Oct, 63(4), 269 - 75
Experimental exposure of young pigs using a pathogenic strain of Streptococcus suis serotype 2 and evaluation of this method for disease prevention; Torremorell M et al.; Control of Streptococcus suis infections and associated disease have proven to be a difficult challenge under most farm conditions . The objective of this study was to experimentally expose young pigs with a pathogenic strain of S . suis serotype 2 as a means of controlling the disease in a commercial swine farm . Prior to the start of the study, the pathogenic S . suis strain responsible for mortality in the farm was identified and used to experimentally inoculate baby piglets . Over a 3-week period, groups of pigs were selected (100 pigs/wk) and divided into 2 groups: control (50 pigs/week) and experimentally exposed (50 pigs/week) . Pigs in the experimentally exposed group were inoculated at 5 d old by tonsillar swabbing with the pathogenic S . suis farm isolate . The effect of exposure with this pathogenic strain was evaluated during the nursery and finishing stages and was based on: morbidity (pigs with central nervous signs (CNS) and/or lameness), mortality and number of treatments required by pigs that had either CNS or lameness . The relative risk (RR) of acquiring disease due to S . suis infection was also calculated . Results showed that morbidity in the experimentally exposed groups was lower than in the control group and these results were statistically different (P = 0.006) . Experimentally exposed pigs also showed a statistically significant reduction in lameness problems (P = 0.012), but not in CNS (P = 0.20) or mortality (P = 0.59) . Pigs in the control group had an increased RR of 4.76, 8.77 and 2.7 for morbidity, to have lameness or to have CNS signs, respectively . In conclusion, experimental exposure of young pigs with the farm's pathogenic S . suis strain at a young age, had a positive effect in reducing clinical signs characteristics of S . suis infection . This method constitutes a novel approach to the control of S . suis infections in swine farms.

Orv Hetil, 1999 Sep 19, 140(38), 2111 - 5
{Non-invasive management of multiple brain abscesses . Case report and review of the literature}; Hoffmann I et al.; The authors report a case and treatment of multiple brain abscesses located in the cerebrum and cerebellum combined with subdural empyema . In conjunction with the case report, the authors review the literature on the pathogenesis of brain abscesses and discuss therapeutic strategies concerning the topic . In the case presented, the primary infection persisted in the lung causing subclinical bronchitis . The hemoculture showed evidence of Streptococcus mitis infection . Although the etiological role of this bacterium in meningitis is known, it rarely causes bacterial meningitis without underlying predisposing factors . In their case, the patient was free of the most common predisposing factors such as congenital heart disease or immunodeficiency . Following the 2 month period of latency, a rapid onset of the symptoms of intracranial inflammation could be observed: fever, headache, meningeal symptoms, focal neurological symptoms and coma . They were not able to identify any bacteria in the cerebrospinal fluid; the Streptocossus mitis could be cultivated only from the haemoculture . The cytological analysis of the cerebrospinal fluid showed typical signs of bacterial infection and the cranial Computed Tomography revealed multiple cerebral abscesses . Neurosurgical intervention was not recommended because of the number, localization and size of the focal lesions . The therapy consisted of intravenous administration of 24 x 10(6) IU/die Penicillin and 4 g/die ceftriaxon . For supportive therapy, Mannitol B, 3 mg/die clonazepam and 300 mg/die phenytoin were administered . Corticosteroids were not used during the course of therapy . Two years later the 55 year old female is symptom free and doing well.

Infect Immun, 1999 Nov, 67(11), 6130 - 8
Bacterial species- and strain-dependent induction of tissue factor in human vascular endothelial cells; Veltrop MH et al.; A cardinal process in bacterial endocarditis (BE) is the activation of the clotting system and the formation of a fibrin clot on the inner surface of the heart, the so-called endocardial vegetation . The processes that lead to the activation of the clotting system on endothelial surfaces upon exposure to bacteria are largely unknown . In the present study, we investigated in an in vitro model whether infection of human endothelial cells (EC) with bacteria that are relevant to BE, such as Staphylococcus aureus, Streptococcus sanguis, and Staphylococcus epidermidis, leads to induction of tissue factor (TF)-dependent procoagulant activity (TFA) and whether this process is influenced by host factors, such as interleukin-1 (IL-1), that are produced in response to the bacteremia in vivo . The results show that S . aureus binds to and is internalized by EC, resulting in expression of TF mRNA and TF surface protein as well as generation of TFA within 4 to 8 h after infection . No TFA was found when EC were exposed to UV-irradiated S . aureus or bacterial cell wall fragments . S . sanguis and S . epidermidis, although also binding to EC, did not induce endothelial TFA . This indicates a species and strain dependency . EC also expressed TFA after exposure to IL-1 . The enhanced TFA of EC after exposure to S . aureus was not prevented by IL-1 receptor antagonist, arguing against an auto- or paracrine contribution of endogenous IL-1 . When IL-1 was applied together with bacteria, this had a synergistic effect on the induction of EC TFA . This was found in particular with S . aureus but also, although to a lesser degree, with S . sanguis and S . epidermidis . This influence of IL-1 on the species- and strain-dependent induction of EC TFA suggests that bacterial factors as well as host factors orchestrate the induction of coagulation in an early stage in the pathogenesis of endovascular disease, such as BE.

Infect Immun, 1999 Nov, 67(11), 6098 - 103
A new rat model of otitis media caused by Streptococcus pneumoniae: conditions and application in immunization protocols; van der Ven LT et al.; Streptococcus pneumoniae (pneumococcus {Pn}) can be cultured from up to 50% of acute otitis media (AOM) effusions, and these bacteria are the most common cause of AOM-related complications . With the recent advent of antibiotic-resistant Pn strains, treatment of Pn infections may meet with serious difficulties . Prevention through vaccination, notably for the four most common occurring Pn serotypes in humans (i.e., Pn 6B, Pn 14, Pn 19F, and Pn 23F), is a helpful alternative . Testing of vaccine efficacy should occur in an appropriate animal AOM model, which is presented here . The four involved Pn serotypes are not pathogenic to the rat, which was chosen as the experimental animal for practical reasons . To induce a natural infection (i.e., ascending through the eustachian tube), the mucociliary clearance of the eustachian tube was impaired by infusing histamine into the tympanic cavity on 2 consecutive days before intranasal inoculation of the bacteria . With this simple protocol, high and reproducible infection rates, as determined with bacterial cultures, of Pn-induced AOM (approximately 70%) with the two major Pn serotypes 14 and 19F (Pn 14 and Pn 19F) were obtained, whereas lower infection rates (25 to 50%) with Pn 6B and Pn 23F were obtained . In this model, intranasal priming with pneumococci, as well as subcutaneous vaccination with Pn 14 tetanus toxoid-conjugated polysaccharide, induced a protective effect against the induction of otitis media with these bacteria . This shows that immunity to Pn 14 AOM can be induced by both mucosal and systemic presentations of antigen . In conclusion, we have developed an animal model for Pn-induced AOM, which is suitable for the evaluation of the protecting effect of immunization.

Infect Immun, 1999 Nov, 67(11), 5979 - 84
Determination of antibody responses of elderly adults to all 23 capsular polysaccharides after pneumococcal vaccination; Rubins JB et al.; The 23-valent pneumococcal polysaccharide vaccine was formulated to prevent invasive infection in the elderly and other high-risk populations from the most prevalent Streptococcus pneumoniae serotypes . However, the immunogenicity of all 23 vaccine polysaccharides has not been fully characterized in elderly adults . We previously reported that whereas the majority of elderly subjects had vigorous immune responses to selected pneumococcal vaccine polysaccharides, a subset of elderly individuals responded to fewer than two of seven vaccine serotypes after immunization . To determine whether these elderly low responders have a general inability to respond to pneumococcal vaccine and to determine whether elderly low responders might be identified by their responses to a few polysaccharides, we measured antibody responses of elderly adults to all 23 vaccine polysaccharides after pneumococcal immunization . As a group, elderly subjects showed a significant rise after immunization in geometric mean antibody levels to all 23 vaccine serotypes . However, when individual rather than group immune responses were assessed, the 23-valent vaccine did not appear to be uniformly immunogenic in these elderly subjects . Eleven elderly subjects (20%) had twofold increases in specific antibody after vaccination to only 5 or fewer of the 23 vaccine polysaccharides, and they did not respond to the most prevalent serotypes causing invasive disease . Antibody responses to serotype 9N were found to reliably distinguish low vaccine responders from other elderly subjects . However, no particular group of vaccine polysaccharides could be used as a marker for adequate immune responses if only postvaccination sera were analyzed.

Infect Immun, 1999 Nov, 67(11), 5892 - 7
Intranasal immunization with pneumococcal polysaccharide conjugate vaccines with nontoxic mutants of Escherichia coli heat-labile enterotoxins as adjuvants protects mice against invasive pneumococcal infections; Jakobsen H et al.; Host defenses against Streptococcus pneumoniae depend largely on phagocytosis following opsonization by polysaccharide-specific immunoglobulin G (IgG) antibodies and complement . Since colonization of the respiratory mucosa is the first step in pneumococcal pathogenesis, mucosal immune responses may play a significant role . In addition to inducing systemic immune responses, mucosal vaccination with an effective adjuvant has the advantage of inducing mucosal IgA antibodies . The heat-labile enterotoxin (LT) of Escherichia coli is a well-studied mucosal adjuvant, and adjuvant activity of nontoxic LT mutants has been demonstrated for several protein antigens . We investigated the immunogenicity of pneumococcal polysaccharide conjugate vaccines (PNC) of serotypes 1 and 3 in mice after intranasal (i.n.) immunization by using as an adjuvant the nontoxic LT mutant LT-K63 or LT-R72, which has minimal residual toxicity . Pneumococcal serotype-specific antibodies were measured in serum (IgM, IgG, and IgA) and saliva (IgA), and vaccine-induced protection was evaluated by i.n . challenge with virulent pneumococci of the homologous serotype . When administered with LT mutants, i.n . immunization with both conjugates induced systemic and mucosal immune responses, and serum IgG antibody levels were significantly higher than after subcutaneous immunization . All mice immunized i.n . with PNC-1 and LT mutants were protected against bacteremia and cleared the pneumococci from the lung 24 h after i.n . challenge; pneumococcal density correlated significantly with serum IgG antibody levels . Similarly, the survival of mice immunized i.n . with PNC-3 and LT mutants was significantly prolonged . These results demonstrate that i.n . vaccination with PNC and potent adjuvants can protect mice against invasive and lethal pneumococcal infections, indicating that mucosal vaccination with PNC may be an alternative vaccination strategy for humans.

Arch Oral Biol, 1999 Oct, 44(10), 871 - 83
Characterization of the mucosal immune response in breast milk after peroral immunization of chimpanzees (Pan troglodytes) with Streptococcus mutans; Tyler BM et al.; The characteristics of the mucosal immune response to Streptococcus mutans cells, antigen A, antigen B, glucosyltransferases and glucan-binding proteins were examined in four pregnant chimpanzees that had been immunized perorally with Strep . mutans . Six pregnant chimpanzees served as non-immunized controls . None of the chimpanzees harbored S . mutans . Samples of milk were collected from all animals throughout the experiment . Peroral immunization resulted in an overall 17-fold median increase in SIgA in milk . Although SIgA1 comprised almost two-thirds of milk SIgA, Strep . mutans whole-cell antibody activity was contained predominantly in the SIgA2 subclass . The difference between the specific activities of anti-Strep . mutans SIgA1 and SIgA2 antibodies compared over time reached the borderline of statistical significance (p = 0.08) . The avidity of anti-Strep . mutans antibodies was low in three of four chimpanzees and there was no evidence of affinity maturation . SIgA antibodies from the milk of all four immunized chimpanzees recognized antigen A . In three animals these antibodies were restricted to the SIgA1 subclass and, in one animal, anti-A antibodies were confined to SIgA2 . Antibodies from all of the immunized chimpanzees recognized degradation products of antigen B in both the SIgA1 and the SIgA2 subclasses . Only two of four immunized chimpanzees responded to glucosyltransferases and these antibodies were restricted to the SIgA1 subclass . None of the chimpanzees responded to the 74-kDa glucan-binding protein . However, three animals produced SIgA1 antibodies against the 59-kDa glucan-binding protein and two of these also produced SIgA2 antibodies against this protein.

Pediatr Infect Dis J, 1999 Oct, 18(10), 902 - 7
Meningitis in pediatric cancer patients: a review of forty cases from a single institution; Sommers LM et al.; BACKGROUND: Although the clinical features of bacterial meningitis in adult cancer patients and in healthy children have been described, no previous large series has described the clinical features of meningitis in pediatric cancer patients . We performed a retrospective review of bacterial or fungal meningitis in pediatric cancer patients to determine its clinical presentation, microbiology and outcome . METHOD: We reviewed the medical records of all patients younger than 18 years old with a diagnoses of any malignancy and bacterial or fungal meningitis at Children's Hospital and Regional Medical Center in Seattle, WA, from January, 1981, to June, 1998 . RESULTS: During the study period there were 40 cases of bacterial or fungal meningitis in 36 pediatric cancer patients . Most patients (65%) had recent neurosurgery, a central nervous system device or cerebrospinal fluid leak . Neutropenia was present in 30% of patients . Fever and altered mental status were the most consistent signs at presentation . In addition at least one additional symptom or sign of meningitis (headache, neck pain or rigidity, seizures or photophobia) was present in 77% of cases . Staphylococcus aureus and Streptococcus pneumoniae were the most common microbiologic isolates . The five patients with fatal outcome were neutropenic . Neutropenia and seizures within 2 days of presentation were associated with long neurologic sequelae . CONCLUSIONS: Meningitis in pediatric cancer patients was associated with significant morbidity and mortality . Pediatric cancer patients with meningitis had clinical features and microbiology distinctly different from those of adult cancer patients and normal children with meningitis.

Clin Infect Dis, 1999 Sep, 29(3), 580 - 5
Penicillin-nonsusceptible Streptococcus pneumoniae at San Francisco General Hospital; Winston LG et al.; Positive pneumococcal cultures of specimens from adult inpatients at San Francisco General Hospital (SFGH) during the period of 11 August 1994 through 31 December 1996 were identified retrospectively . Of the isolates recovered, 15.5% were not penicillin-susceptible (MIC, > or =.1 microg/mL) . A case-control study was performed to evaluate risk factors for colonization or infection with penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) and outcomes . Cases (n = 65) were adult inpatients with a positive culture for PNSP, and controls (n = 411) were adult inpatients with a positive culture for penicillin-susceptible pneumococci (PSSP) and no evidence of PNSP . Cases were less likely to have pneumococcal bacteremia (15.4% versus 39.4%; P<.001) and less likely to have pneumonia (50.8% versus 68.9%; P = .006) . In a multiple logistic regression model, recent hospital admission and absence of bacteremia were independent predictors of penicillin-nonsusceptibility . Human immunodeficiency virus infection, mortality, and length of hospitalization were not significantly different among cases and controls . These data suggest that PNSP may be less virulent (cause less pulmonary infection) and/or less invasive (cause fewer bloodstream infections) than PSSP at SFGH.

Int Endod J, 1999 May, 32(3), 197 - 203
A comparison of MTA, Super-EBA, composite and amalgam as root-end filling materials using a bacterial microleakage model; Adamo HL et al.; AIM: The aim of this study was to compare traditional and newly developed root-end filling materials for resistance to bacterial microleakage . METHODOLOGY: Sixty extracted single-rooted teeth were randomly divided into five groups for root-end filling with mineral trioxide aggregate, Super-EBA, TPH composite resin with ProBond dentine bonding agent, Dispersalloy amalgam with and without ProBond, and positive and negative control groups . Root canals were instrumented using the step-back technique and simulated root-end resections performed . Root-end filling materials were placed in 3 mm ultrasonic retropreparations . Nail varnish was applied to all external root surfaces to the level of the resected root ends to prevent lateral microleakage . Samples were sterilized in an ethylene oxide sterilizer for 12 h . Using a newly designed model system, the apical 3-4 mm of the roots were immersed in BHI culture medium with phenol red indicator within culture chambers . The coronal access of each specimen was inoculated every 48 h with a suspension of Streptococcus salivarius . Culture media were observed every 24 h for colour change indicating bacterial contamination . Media demonstrating colour change were plated for S . salivarius . Samples were observed for 12 weeks . RESULTS: At 4 weeks 10% of specimens from each experimental group had evidence of leakage . At 8 weeks 20% of specimens filled with amalgam without dentine bonding agent, Super-EBA and MTA had evidence of leakage . At 12 weeks minor differences between materials were noted . CONCLUSIONS: Under the conditions of the study, despite some variations, there were no statistically significant differences in rate of microleakage among the five groups tested at either 4, 8 or 12 weeks.

Caries Res, 1999 Nov-Dec, 33(6), 446 - 54
Powdered milk micellar casein prevents oral colonization by Streptococcus sobrinus and dental caries in rats: a basis for the caries-protective effect of dairy products; Guggenheim B et al.; Three animal studies were performed to investigate the influence of the macromolecular structure of milk casein on caries incidence and the possible ecological changes of the oral microbiota by such casein fractions . Towards this end, rats were infected with mixed bacterial suspensions of Streptococcus sobrinus OMZ 176 and Actinomyces viscosus Ny1 . Various milk protein fractions were incorporated into carefully balanced powdered cariogenic diets to constitute the sole major protein component . Diets containing micellar casein had a pronounced and highly significant effect on almost all clinical and microbiological parameters examined . Both the formation of advanced dentinal fissure (B) and smooth surface (E) caries lesions was inhibited by diets containing micellar casein; this caries-inhibiting effect appeared to be due mainly to modifications within the plaque microbiota . The proportion of S . sobrinus in the oral cavity of rats was reduced (73-80%) by micellar casein-containing preparations, whereas the A . viscosus population was increased . Both these microbiological parameters were always negatively correlated . This appears to be the first example of a food component other than dietary sugars, selectively modifying the composition of the dental plaque microbiota of rats in such a way as to reduce its pathogenic potential . It also demonstrates the importance of establishing a molecular basis for the role of food components, which prove to be beneficial to oral health.

Scand J Infect Dis, 1999, 31(4), 409 - 10
Recurrent endocarditis caused by Streptococcus pneumoniae; Lindberg J et al.; Pneumococcal endocarditis most often presents as an ulcerative endocarditis causing rapid destruction of the normal aortic valve, leading to aortic insufficiency and acute heart failure . Alcoholism is the most frequent underlying medical condition . This case illustrates that pneumococcal endocarditis can reoccur and is able to attack healthy, as well as previously damaged, heart valves . It also illustrates that vaccination of certain groups should be considered . The importance of repeated heart stethoscopy in patients with pneumococcaemia is emphasized.

Scand J Infect Dis, 1999, 31(4), 367 - 70
Lower lipoteichoic and teichoic acid CSF concentrations during treatment of pneumococcal meningitis with non-bacteriolytic antibiotics than with ceftriaxone; Stuertz K et al.; In the rabbit model of Streptococcus pneumoniae meningitis, treatment with rifabutin, quinupristin-dalfopristin, moxifloxacin and trovafloxacin led to smaller increases of the CSF concentrations of the pro-inflammatory cell wall components lipoteichoic and teichoic acids (LTA and TA) than did treatment with ceftriaxone . Low doses of moxifloxacin were associated with higher LTA and TA concentrations in CSF than were high doses.

Zentralbl Veterinarmed B, 1999 Sep, 46(7), 433 - 42
Epidemiology of Streptococcus uberis intramammary infections in a dairy herd; Jayarao BM et al.; From 1987 to 1991, almost 36,000 quarter samples of mammary secretion representing 1790 lactations of 510 dairy cows from a research herd were collected for bacteriological examination . The percentage of cows infected with Streptococcus uberis ranged from 12 to 16% of cows/year . S . uberis was isolated from 14.2% of lactations over the 5-year period . The prevalence of S . uberis intramammary infection (IMI) was significantly higher in cows with > or = 4 lactations than in cows with 3 or fewer lactations . Regardless of lactation number, the prevalence of S . uberis was highest before parturition, during early lactation and near drying off . The prevalence of S . uberis infected quarters ranged from 1.3 to 2.3% of quarters/year; the prevalence rate for the 5-year period was 2% of quarters . The quarter prevalence of S . uberis was lowest in cows with < or = 3 lactations, increased significantly with lactation number and was highest in cows with > or = 6 lactations . The percentage of quarters infected with S . uberis varied significantly by year . The majority (95%) of S . uberis IMI were subclinical . The ratio of subclinical IMI to clinical IMI was lowest during early lactation, and increased with days in milk, and with lactation age except for cows in their 5th and 6th lactations . Results of this epidemiological investigation suggest that opportunities exist where suitable control measures could be applied to reduce the impact of S . uberis infections in the dairy herd.

Domest Anim Endocrinol, 1999 Oct, 17(2-3), 149 - 59
Modulation of the inflammatory reaction and neutrophil defense of the bovine lactating mammary gland by growth hormone; Burvenich C et al.; This review is focused on the possible interactions of prolactin and somatotrope hormone in the modulation of inflammation of the mammary gland . Several different models are examined: Escherichia coli, Streptococcus uberis, and endotoxin mastitis . Subsequently, the release of growth hormone and insulin-like growth factor during fever and mastitis, the immunophysiological effects of GH on E . coli mastitis, S . uberis and endotoxin mastitis, the galactopoietic action of rBST on healthy and mastitis cows as well as the immunologic effects of GH on leukocytes in healthy and diseased cows are discussed . It can be concluded that the underlying regulation of the neuro-endocrine network is fundamental in the normal function of the immune system.

Curr Microbiol, 1999 Dec, 39(6), 321 - 0326
Isolation and characterization of promoter regions from Streptococcus gordonii CH1; Vriesema AJ et al.; We aimed to identify transcription signal sequences from Streptococcus gordonii strain CH1 by random chromosomal cloning . Five genomic fragments from a Sau3A digest, which constitutively activated transcription of a promoterless spectinomycin resistance gene in this strain, were isolated and characterized . Additionally, one promoter fragment was isolated that was specifically activated under iron-limiting conditions . A sequence motif with similarity to the consensus for Fur-binding regulatory DNA sequences (Fur box) in Escherichia coli was detected within the putative promoter region . The open reading frame downstream of this region possibly encodes a transmembrane protein involved in iron uptake.

Methods, 1999 Sep, 19(1), 163 - 73
Engineering the gram-positive cell surface for construction of bacterial vaccine vectors; Oggioni MR et al.; A genetic system for surface display of heterologous proteins has been developed in Streptococcus gordonii, a gram-positive human oral commensal that is naturally competent for genetic transformation . Our approach is based on chromosomal integration downstream from a resident promoter and translational fusion to an M6 protein . Using this strategy a variety of proteins, of different origin and size, were displayed on the cell surface and were shown to be stably expressed both in vitro and in vivo . Animal models of mucosal colonization (oral and vaginal) and intragastric immunization with recombinant S . gordonii were developed and the local and systemic immune responses were studied . Here we report the techniques for the construction of recombinant bacteria, use of animal models, and analysis of the immune response .

Clin Infect Dis, 1999 Nov, 29(5), 1274 - 80
Marked differences in pneumococcal carriage and resistance patterns between day care centers located within a small area; Givon-Lavi N et al.; Carriage rates of Streptococcus pneumoniae and their antibiotic resistance, capsular types, and genetic patterns were studied among 264 children aged 12-35 months attending 8 day care centers located within a 2.5-mile radius in the same city . Nasopharyngeal cultures were obtained within a 2-month interval from all 264 children . Significant differences in each of the studied characteristics were found between day care centers, and each day care center had a unique pattern of the carried pneumococci . Our findings show that day care centers are independent microenvironments and emphasize their role in the transmission and augmentation of antibiotic-resistant S . pneumoniae in the community.

Clin Infect Dis, 1999 Nov, 29(5), 1257 - 64
Carriage of multidrug-resistant Streptococcus pneumoniae and impact of chemoprophylaxis during an outbreak of meningitis at a day care center; Craig AS et al.; Three cases of meningitis due to multidrug-resistant serotype 14 Streptococcus pneumoniae occurred at a day care center (DCC) over 5 days . Cultures of nasopharyngeal samples were done at the index DCC, 2 comparison DCCs, and a pediatrics practice . Isolates were serotyped and subtyped by pulsed-field gel electrophoresis (PFGE) with SmaI . Pneumococcal carriage rates ranged from 44%-65% at the 3 DCCs and 29% in the pediatrics practice . Carriage of multidrug-resistant serotype 14 S . pneumoniae was noted in 13%-19% of children at the 3 DCCs . An outbreak strain was identified by PFGE at the index DCC and 1 other DCC; a closely related strain was found in the third DCC . Carriage of the outbreak strain was associated with being age 0-24 months, antibiotic use, upper respiratory tract infections, and otitis media . DCC contacts of the ill children were offered chemoprophylaxis with rifampin and clindamycin, which produced a profound but transient decrease in carriage . No additional cases occurred.

Clin Infect Dis, 1999 Nov, 29(5), 1186 - 8
Prevalence of macrolide resistance mechanisms in Streptococcus pneumoniae isolates from a multicenter antibiotic resistance surveillance study conducted in the United States in 1994-1995; Shortridge VD et al.; Two main mechanisms of macrolide resistance have been described in erythromycin-resistant Streptococcus pneumoniae (ERSP): a ribosomal methylase, ErmAM, and a macrolide efflux pump, MefE . In this study, we examined the prevalence of these mechanisms in 114 clinical isolates of ERSP from a 30-center study conducted in the United States between November 1994 and April 1995 . The isolates were screened by polymerase chain reaction for the presence of known macrolide resistance genes . Seventy (61%) ERSP contained the macrolide efflux gene (mefE), whereas 36 isolates (32%) contained the biosomal methylase gene (ermAM) . Isolates that were ermAM-positive had constitutive macrolide resistance . The minimum inhibitory concentrations (for which 90% of isolates were susceptible) of clarithromycin for the efflux-positive strains were much lower than those for the ermAM-positive strains (4 microg/mL vs . >128 microg/mL, respectively) . The efflux mechanism is the predominant form of macrolide resistance in the United States.

J Clin Microbiol, 1999 Nov, 37(11), 3681 - 7
Genotypic and phenotypic characterization of "Streptococcus milleri" group isolates from a Veterans Administration hospital population; Clarridge JE 3rd et al.; Because identification of the species within the "Streptococcus milleri" group is difficult for the clinical laboratory as the species share overlapping phenotypic characteristics, we wished to confirm biochemical identification with identification by 16S rRNA gene sequence analysis . Ninety-four clinical isolates previously identified as the "Streptococcus milleri" group were reclassified as S . anginosus, S . constellatus, or S . intermedius with the API 20 Strep system (bioMerieux Vikek, Hazelton, Mo.) and the Fluo-card (Key Scientific, Round Rock, Tex.) . In addition, we determined the Lancefield group, hemolysis, colony size, colony texture, repetitive extragenic palindromic PCR (rep-PCR) pattern, and cellular fatty acid (CFA) profile (MIDI, Newark, Del.) . 16S rRNA gene sequence analysis with 40 selected representative strains showed three distinct groups, with S . constellatus and S . intermedius found to be more closely related to each other than to S . anginosus, and further distinguished a biochemically distinct group of urogenital isolates within the S . anginosus group of isolates . Except for strains unreactive with the Fluo-card (8%), all S . anginosus and S . intermedius strains identified by sequencing were similarly identified by biochemical testing . However, 23% of the selected S . constellatus isolates identified by sequencing (9% of all S . constellatus isolates) would have been identified as S . anginosus or S . intermedius by biochemical tests . Although most S . anginosus strains formed one unique cluster by CFA analysis and most S . constellatus strains showed similar rep-PCR patterns, neither method was sufficiently dependable for identification . Whereas Lancefield group or lactose fermentation did not correspond to sequence or biochemical type, S . constellatus was most likely to be beta-hemolytic and S . intermedius was most likely to have a dry colony type . The most frequent isolate in our population was S . constellatus, followed by S . anginosus . There was an association of S . anginosus with a gastrointestinal or urogenital source, and there was an association of S . constellatus and S . intermedius with both the respiratory tract and upper-body abscesses.

J Clin Invest, 1999 Oct, 104(8), 1139 - 47
Killing of Streptococcus pneumoniae by capsular polysaccharide-specific polymeric IgA, complement, and phagocytes; Janoff EN et al.; The role of IgA in the control of invasive mucosal pathogens such as Streptococcus pneumoniae is poorly understood . We demonstrate that human pneumococcal capsular polysaccharide-specific IgA initiated dose-dependent killing of S . pneumoniae with complement and phagocytes . The majority of specific IgA in serum was of the polymeric form (pIgA), and the efficiency of pIgA-initiated killing exceeded that of monomeric IgA-initiated killing . In the absence of complement, specific IgA induced minimal bacterial adherence, uptake, and killing . Killing of S . pneumoniae by resting phagocytes with immune IgA required complement, predominantly via the C2-independent alternative pathway, which requires factor B, but not calcium . Both S . pneumoniae-bound IgA and complement were involved, as demonstrated by a 50% decrease in killing with blocking of Fcalpha receptor (CD89) and CR1/CR3 (CD35/CD11b) . However, IgA-mediated killing by phagocytes could be reproduced in the absence of opsonic complement by pre-activating phagocytes with the inflammatory products C5a and TNF-alpha . Thus, S . pneumoniae capsule-specific IgA may show distinct roles in effecting clearance of S . pneumoniae in the presence or absence of inflammation . These data suggest mechanisms whereby pIgA may serve to control pneumococcal infections locally and upon the pathogen's entry into the bloodstream.

Microbiol Immunol, 1999, 43(8), 807 - 12
Limited stress response in Streptococcus pneumoniae; Choi IH et al.; In Streptococcus pneumoniae, heat shock induces the synthesis of 65-, 73-, and 84-kDa proteins, and ethanol shock induces a 104-kDa protein . In this study, the 65-, 84-, and 104-kDa proteins were identified as members of the GroEL, ClpL and alcohol dehydrogenase families, respectively, and the general properties of the stress response of S . pneumoniae to several other stresses were characterized . However, several stresses which are known to induce stress responses in Escherichia coli and Bacillus subtilis failed to induce any high molecular weight heat-shock proteins (HSPs) such as GroEL and DnaK homologues . A minor temperature shift from 30 to 37 C triggered induction of the homologues of DnaK and GroEL of E . coli . These features may provide a foundation for evaluating the role of heat-shock proteins relative to the physiology and pathogenesis of pneumococcus.

Infect Dis Obstet Gynecol, 1999, 7(5), 227 - 9
Semiquantitative bacterial observations with group B streptococcal vulvovaginitis; Monif GR; OBJECTIVE: Group B streptococcal (GBS) vulvovaginitis is a poorly-delineated clinical entity . The purpose of this study is to report semiquantitative data from four cases of GBS vulvovaginitis and to comment on their significance in terms of the in vitro inhibitory capabilities of GBS . METHODOLOGY: Four patients whose clinical presentations were consistent with GBS vulvovaginitis, from whom GBS was isolated and for whom semi-quantitative as well as qualitative microbiologic data existed, were identified . RESULTS: To produce vulvovaginitis, GBS must be at a high multiplicity (10(8) CFU/g of vaginal fluid) . Single coisolates were identified in three of the four cases (two cases of Escherichia coli and one case of Staphylococcus aureus) . Group B streptococcus does not inhibit either of these bacteria in vitro . CONCLUSION: When the growth requirements for the demonstration of in vitro inhibition for GBS or lack thereof are met in vivo, the in vivo observations are consistent with those projected from the in vitro data.

Gene, 1999 Sep 3, 237(1), 223 - 34
Domain organization and molecular characterization of 13 two-component systems identified by genome sequencing of Streptococcus pneumoniae; Lange R et al.; In bacteria, adaptive responses to environmental stimuli are often initiated by two-component signal transduction systems (TCS) . The prototypical TCS comprises two proteins: a histidine kinase (HK, hk) and a response regulator (RR rr) . Recent research has suggested that compounds that inhibit two-component systems might have good antibacterial activity . In order to identify TCS that are crucial for growth or virulence of Streptococcus pneumoniae, we have examined the genomic sequence of a virulent S . pneumoniae strain for genes that are related to known histidine kinases or response regulators . Altogether 13 histidine kinases and 13 response regulators have been identified . The protein sequences encoded by these genes were compared with sequences deposited in public databases . This analysis revealed that two of the 13 pneumococcal TCSs have been described before (ciaRH and comDE) and two are homologous to the yycFG and the phoRP genes of Bacillus subtilis . All the pneumococcal response regulators contain putative DNA binding motifs within the C-terminal output domain, implying that they are involved in transcriptional control . Two of these response regulators are obviously the first representatives of a new subfamily containing an AraC-type DNA-binding effector domain . To assess the regulatory role of these transcription factors, we disrupted each of the 13 response regulator genes by insertional mutagenesis . All the viable mutant strains with disrupted response regulator genes were further characterized with regard to growth in vitro, competence, and experimental virulence . Two response regulator genes could not be inactivated, indicating that they may regulate essential cellular functions . The possibility of using these systems as targets for the development of novel antibacterials will be discussed.

J Clin Microbiol, 1999 Nov, 37(11), 3759 - 60
A serotype VIII strain among colonizing group B streptococcal isolates in Boston, Massachusetts; Paoletti LJ et al.; Maternal colonization with group B Streptococcus (GBS) is a risk factor for neonatal GBS disease . Whereas serotypes Ia, Ib, II, III, and V are prevalent in the United States, types VI and VIII predominate in Japan . Recently, a serotype VIII strain was detected among 114 clinical GBS isolates from a Boston, Mass., hospital.

J Clin Microbiol, 1999 Nov, 37(11), 3707 - 10
Predicting susceptibility of Streptococcus pneumoniae to ceftriaxone and cefotaxime by cefuroxime and ceftizoxime disk diffusion testing; Williams-Bouyer N et al.; In this study, disk diffusion testing with ceftizoxime and cefuroxime was evaluated for use in predicting the susceptibility of Streptococcus pneumoniae to ceftriaxone and cefotaxime . Of the 194 isolates included in this study, 138 were susceptible, 34 were intermediate, and 22 were resistant to cefotaxime by MIC testing; 138 isolates were susceptible, 35 were intermediate, and 21 were resistant to ceftriaxone by MIC testing . A zone of inhibition around the cefuroxime disk of >/=32 mm correctly categorized 101 of 138 isolates as susceptible to cefotaxime and ceftriaxone . A zone of inhibition around the ceftizoxime disk of >/=26 mm correctly categorized 111 of 138 isolates as susceptible to cefotaxime and 114 of 138 as susceptible to ceftriaxone . We conclude that disk diffusion can separate S . pneumoniae isolates susceptible to ceftriaxone and cefotaxime from those that are not susceptible . Isolates not falling into the susceptible category by disk diffusion require additional testing to determine the MIC.

Laryngoscope, 1999 Oct, 109(10), 1674 - 8
Effects of depletion of complement in the development of labyrinthitis ossificans; DeSautel MG et al.; HYPOTHESIS: Labyrinthitis ossificans results in part from the intense inflammatory response to Streptococcus pneumoniae cell wall components . Depletion of complement in Mongolian gerbils following induction of meningitis will reduce the degree of inflammation and subsequent cochlear fibrosis . STUDY DESIGN: Random prospective study . Histological evaluations were performed with the researcher blinded to the experimental group METHODS: S . pneumoniae meningitis was induced in 10 control and 18 experimental Mongolian gerbils with an intrathecal injection of the bacteria . Both groups of animals received treatment with penicillin . The experimental group was also treated with cobra venom factor to deplete complement in the animals . Three months after the induction of meningitis, the animals' temporal bones were harvested for histological evaluation . RESULTS: The decomplemented animals developed significantly less intracochlear fibrosis (P < .01) . The mortality rate for the experimental group was 11% compared with 40% in the control group (P = .14) . CONCLUSIONS: Reduction of the intense inflammatory response to the S . pneumoniae cell wall components in suppurative labyrinthitis secondary to bacterial meningitis reduced the degree of labyrinthitis ossificans.

Oral Dis, 1999 Apr, 5(2), 92 - 9
Molecular pathogenesis of root dentin caries; Dung TZ et al.; Human dentin has a higher content of organic matrix and more non-ideal hydroxyapatite than human enamel . Ultrastructural studies indicate that root caries involves both mineral dissolution and breakdown of the organic matrix . Factors involved in the root caries process seem more complicated than those in enamel caries . Moreover, the distinct roles of acids and enzymes and the sequence of events in the root caries process are not well-understood . Although Streptococcus mutans and Actinomyces viscosus are considered to be major pathogenic micro-organisms of root caries, their roles in degradation of the organic matrix components of root dentin need clarification . The purpose of this paper is to review the basic composition of root dentin and the roles of acids and both endogenous and bacterial enzymes in the root caries process.

Am J Obstet Gynecol, 1999 Oct, 181(4), 803 - 8
A randomized trial of conjugated group B streptococcal type Ia vaccine in a rabbit model of ascending infection; Davies JK et al.; OBJECTIVE: Maternal vaccination may become a central strategy in the prevention of early-onset group B Streptococcal sepsis . Unlike earlier group B streptococcal polysaccharide vaccines that were poorly immunogenic, newer vaccines conjugated to tetanus toxoid have been developed and have improved immunogenicity . We sought to evaluate a conjugated vaccine using our rabbit model of ascending infection . STUDY DESIGN: Rabbit does were randomized to receive either conjugated group B streptococcal type Ia (Ia-tetanus toxoid) or conjugated group B streptococcal type III (III-tetanus toxoid) vaccine . Does were vaccinated 7 days before conception and 7 and 21 days after conception . On days 28 to 30 of a 30-day gestation, does were inoculated intracervically with 10(6) colony-forming units of type Ia group B Streptococcus . Labor was induced if does were undelivered after 72 hours . Does were observed up to 7 days after inoculation . Offspring were observed up to 4 days . We obtained maternal cultures from the uterus, peritoneum, and blood and offspring cultures from the mouth, anus, and blood . Antibody levels were also determined . RESULTS: Offspring survival was significantly improved in the group receiving Ia-tetanus toxoid (P =.047) . Outcomes such as maternal sepsis and severe illness, although not reaching statistical significance, showed a trend toward improved outcomes in the Ia-tetanus toxoid group . CONCLUSIONS: This is the first study to evaluate the conjugated group B streptococcal vaccine by using any model of ascending infection . The Ia-tetanus toxoid vaccine led to improved survival and was immunogenic but fell short of its expected efficacy in preventing ascending group B streptococcal disease under these experimental conditions.

Acta Paediatr, 1999 Sep, 88(9), 1031 - 2
Neonatal Group B Streptococcal bacteraemia in India: ten years' experience; Kuruvilla KA et al.; Group B Streptococcus (GBS) is an infrequent cause of neonatal septicaemia in many developing countries . In a perinatal centre in India with 60,119 live births between 1988 and 1997, GBS was isolated from blood cultures of 10 babies . Thus the incidence of GBS bacteraemia was 0.17 per 1000 live births . Lethargy, respiratory distress and poor perfusion were the presenting features in eight symptomatic babies . Two babies had meningitis, three required ventilatory support and one died . There were no cases of late onset disease . The low incidence could be due to the low rate of colonisation and high prevalence of protective antibody in the mothers.

J Clin Dent, 1998, 9(3), 64 - 6
Preliminary report: laboratory-induced stain removal as assessed by environmental scanning electron microscopy; Habib CM et al.; Environmental scanning electron microscopy (ESEM) was employed to observe stain removal during brushing with Arm & Hammer Dental Care and Crest Regular Toothpaste . ESEM allows serial examinations of the same sample, and does not require a destructive preparative process . Three extracted molars were cleaned, placed into a 96-hour broth culture of Streptococcus mutans, and stain was produced with undiluted chlorhexidine rinse, concentrated coffee and tea for a period of 23 days . After staining, the teeth were examined by ESEM, then brushed using a toothbrushing machine . Imaging was repeated after 5, 10, 15 and 30 seconds of brushing . As seen with ESEM, the Arm & Hammer product had different effects than those from the distilled water control, suggesting something other than that expected from abrasive and mechanical forces alone . There were also differences from the Crest dentifrice removal on this single sample, suggesting a possible difference between the two products . Further studies are needed to confirm and explain these effects.

J Clin Dent, 1998, 9(2), 46 - 8
An in vitro investigation of the antimicrobial activity of an herbal mouthrinse; Kaim JM et al.; The purpose of this study was to determine the antimicrobial activity of one prescription and two commercially available over-the-counter mouthrinses and positive and negative controls against bacteria commonly found in the oral cavity . The bacteria used in this study were Streptococcus mutans, Streptococcus sanguis and Actinomyces viscosus . Sterile discs which were treated with the mouthrinses were placed on agar plates along with the controls . Zones of microbial inhibition were measured in millimeters after 48 hours . The results indicated that all of the mouthrinses demonstrated antimicrobial activity against the bacteria tested . Herbal Mouth and Gum Therapy mouthrinse, containing natural ingredients, produced the largest zones of microbial inhibition when compared to Listerine against all three of the bacteria tested . Herbal Mouth and Gum Therapy mouthrinse produced larger zones of microbial inhibition when compared to Peridex against two of the three bacteria tested, and produced similar zones of inhibition against the third bacteria.

FEMS Microbiol Lett, 1999 Oct 15, 179(2), 485 - 90
Natural genetic transformation in the rumen bacterium Streptococcus bovis JB1; Mercer DK et al.; Natural transformation of Streptococcus bovis JB1 was demonstrated after development of competence in normal culture medium . Transformation efficiencies were not significantly increased when heat-inactivated horse serum was added to the medium before growth . This is the first time that a resident rumen bacterial species has been shown to be naturally transformable . Transformation allowed the acquisition of plasmids or integration of sequences into the chromosome . No transformation was observed in the presence of undiluted autoclaved or filter-sterilised ovine rumen fluid or filter-sterilised ovine saliva, suggesting that transformation in the ruminant digestive tract is a rare event, although transformation was observed in the presence of 1% and 0.5% filter-sterilised rumen fluid . The use of natural transformation of S . bovis should facilitate further molecular biological studies on this species.

FEMS Microbiol Lett, 1999 Oct 15, 179(2), 297 - 304
Genetic analysis of turbot pathogenic Streptococcus parauberis strains by ribotyping and random amplified polymorphic DNA; Romalde JL et al.; Ribotyping and RAPD profiling of a collection of 18 Streptococcus parauberis strains isolated from diseased turbot in Galicia (NW Spain) was performed in order to analyze the possible genetic variability within this bacterial fish pathogen . In addition, the value of this technique for intraspecific classification and epidemiological studies was evaluated . Ribopatterns of DNA digested with three endonucleases and hybridized with a cDNA probe complementary to highly conserved sequences in the 16S and 23S rRNA genes showed a great homogeneity among the turbot isolates . Compared with ribotyping, RAPD appeared to be a reliable and fast technique for discriminating between isolates of S . parauberis on the basis of their farm of isolation and, therefore, represents a powerful tool for epidemiological studies of this fish pathogen.

Eur J Clin Microbiol Infect Dis, 1999 Aug, 18(8), 545 - 50
Low prevalence of the immunoglobulin-A-binding beta antigen of the C protein among Streptococcus agalactiae isolates causing neonatal sepsis; Berner R et al.; Streptococcus agalactiae (Group B streptococcus, GBS) is the most important pathogen causing neonatal sepsis . The role of bacterial proteins contributing to pathogenicity in GBS infections has not yet been clearly determined, but the C protein complex has been suggested to be involved in both virulence and protective immunity . The aim of this study was to assess the prevalence of GBS strains bearing the gene encoding for the beta antigen of the C protein among clinical isolates from 68 neonates with sepsis, 45 newborns colonized without clinical signs of infection, and 50 isolates from pregnant women . The prevalence of the beta antigen gene in all three groups was low (24% vs . 19% vs . 22%) {corrected}, and the differences between groups were not statistically significant . Clinical characteristics and cytokine plasma levels did not differ between septic patients with beta antigen-positive and -negative strains . The beta-antigen gene was not found among serotype III isolates, which accounted for roughly half of all the strains isolated . Thus, polymerase chain reaction (PCR) analysis based on the beta antigen gene seems not helpful for distinguishing invasive from colonizing GBS strains . A vaccine based on peptide antigens from the beta antigen of the C protein would most probably not provide protection against the majority of GBS isolates . When analyzing the PCR products of the C protein beta antigen gene by DNA sequencing, a genetic heterogeneity was observed, revealing small repetitive genetic elements within the amplified fragment, an observation that should be studied further.

Microbiology, 1999 Sep, 145 ( Pt 9), 2605 - 13
Genetic approaches to the identification of the mitis group within the genus Streptococcus; Kawamura Y et al.; The usefulness and reliability of partial sequence analysis of the manganese-dependent superoxide dismutase gene (sodA), autolysin (lytA) gene amplification and species-specific PCR based on the D-alanine:D-alanine ligase (ddl) gene for differentiating each member of the mitis group of the genus Streptococcus was investigated . On the phylogenetic tree based on sodA partial sequences (366 bp) from 96 strains, including all species currently within the mitis group isolated in different geographic areas (mainly Japan and the UK), eight well separated clusters were generated corresponding to recognized species, and all strains fell into those clusters to which they had also been assigned by DNA-DNA hybridization . The Streptococcus pneumoniae sub-cluster was located within the Streptococcus mitis cluster, but the sodA gene of S . pneumoniae was very conserved and therefore could be separated from all other species examined . Furthermore, the lytA gene amplification approach could also be used to differentiate S . pneumoniae from other species . The species-specific amplification product of the ddl gene was successfully detected in Streptococcus sanguinis and Streptococcus gordonii, but failed to be detected in some strains of Streptococcus oralis including the type strain and S . mitis . We conclude that the partial sequence analysis of the sodA gene could be applied globally as a reliable and easy method for the accurate identification of all species currently within the mitis group.

Respiration, 1999, 66(5), 413 - 8
Treatment of community-acquired pneumonia in outpatients: randomized study of clarithromycin alone versus clarithromycin and cefuroxime; Rovira E et al.; OBJECTIVE: To evaluate the efficacy of clarithromycin alone in comparison with the combination of clarithromycin and cefuroxime in the treatment of nonhospitalized patients with community-acquired pneumonia (CAP) in a Mediterranean population . METHODS: CAP was defined as the acute onset of fever (>38 degrees C) with pulmonary opacity on chest roentgenogram . The American Thoracic Society (ATS) criteria (1993) were used to decide on patient hospitalization . Ninety subjects, of whom 53 (59%) were men, with a mean age (+/-SD) of 38+/-15 years, were randomized: 45 received clarithromycin 500 mg b.i.d . orally for 14 days (CL group), and 45 received clarithromycin plus cefuroxime 500 mg b.i.d . orally for 7 days (CLCE group) . Patients were monitored with clinical, radiological, and laboratory controls at 3 and 21 days . There were no significant differences between the two groups with regard to demographic, clinical, physical and laboratory data . RESULTS: The mean time to defervescence was 2.4+/-1.4 and 2.4+/-1.5 days, respectively . Chest roentgenogram clearance was complete in all cases, without statistically significant differences in the time to resolution between both arms . Side effects were mild (no significant differences between groups): 5 patients in the CL group and 3 in the CLCE group showed gastrointestinal symptoms . Two patients (2.2%), both in the CLCE group, needed hospital admission during follow-up, but all 90 patients showed an excellent outcome . A causative agent was determined in 25 cases (28%) . Legionella pneumophila, Streptococcus pneumoniae, and Mycoplasma pneumoniae were the most frequent pathogens . CONCLUSION: Empirical treatment of outpatient CAP with clarithromycin can be considered adequate in the Mediterranean area, independently of the microbiological etiology . ATS criteria for admitting patients with CAP are appropriate in this population.

J Infect Dis, 1999 Nov, 180(5), 1722 - 6
YKL-40, a matrix protein of specific granules in neutrophils, is elevated in serum of patients with community-acquired pneumonia requiring hospitalization; Nordenbaek C et al.; The serum concentration of YKL-40, a matrix protein of specific granules in neutrophils, was determined by RIA in 90 patients hospitalized with pneumonia of suspected bacterial origin . Of these, 64 were followed prospectively during antibiotic treatment with blood samples taken on day 0 (on admission and the start of treatment) and on days 1, 3, 5, 7, 10, and 21 . Serum YKL-40 at admission was increased in patients with Streptococcus pneumoniae pneumonia (median, 893 microgram/L; 95% confidence interval {CI}, 704-1560), compared with healthy subjects (median, 102 microgram/L; 95% CI, 64-247 microgram/L; P<.001) and in patients with pneumonia of unknown etiology (median, 448 microgram/L; 95% CI, 334-700; P<.05) . Peak YKL-40 serum values were observed on day 1 and thereafter declined steeply to almost normal by day 3 . During the first 10 days, there was a close relation between serum YKL-40 and markers of specific granules of neutrophils (serum lactoferrin and neutrophil gelatinase-associated lipocalin), which suggests that serum YKL-40 reflects exocytosis of specific granules of neutrophils in persons with acute bacterial pneumonia.

J Infect Dis, 1999 Nov, 180(5), 1718 - 21
Tumor necrosis factor-alpha and interleukin-1alpha decrease the adherence of Streptococcus pyogenes to cultured keratinocytes; Darmstadt GL et al.; We hypothesized that the primary epidermal cytokines, tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha, which are produced after skin injury, modulate bacterial adherence and the initiation of group A streptococcal skin infections . Streptococcus pyogenes binds preferentially to highly differentiated keratinocytes in vitro, simulating the superficial human skin infection, impetigo, and providing a model system for testing this hypothesis . Exposure of keratinocytes to 10 ng/mL TNF-alpha for 20 h decreased adherence to undifferentiated and differentiated keratinocytes by 33% and 38%, respectively . Treatment with 1 ng/mL IL-1alpha decreased adherence to undifferentiated and differentiated keratinocytes by 23% and 18%, respectively . Exposure to both cytokines simultaneously produced an additive 50% reduction in adherence . These data suggest that TNF-alpha and IL-1alpha may play a role in cutaneous host defense by impeding streptococcal adherence and decreasing its ability to form a nidus of infection in the skin.

J Infect Dis, 1999 Nov, 180(5), 1577 - 83
Characterization of a multidrug-resistant clone of invasive Streptococcus pneumoniae serotype 6B in Alaska by using pulsed-field gel electrophoresis and PspA serotyping; Rudolph KM et al.; Antimicrobial susceptibility, pneumococcal surface protein A (PspA) serotyping, and pulsed-field gel electrophoresis (PFGE) were used to evaluate clonal relatedness among 66 invasive isolates of Streptococcus pneumoniae serotype 6B collected during 1982-1996 from patients in Alaska . Thirty-seven (56%) of the isolates had penicillin minimal inhibitory concentration values >/=0.125 microgram/mL and were resistant to at least 1 other antibiotic . Fourteen PspA serotypes were observed; PspA 16 was the most common (35%) . Forty-five (68%) of the 66 isolates shared common and highly related PFGE patterns using 3 enzymes . Twenty-six (58%) of the isolates with common PFGE patterns were from Native Alaskan children </=2 years of age residing in 1 region of Alaska . Alaskan serotype 6B had distinct PFGE patterns, compared with the South African 6B-8 and Spanish 6B-2 multidrug-resistant clones, suggesting that the Alaskan 6B isolates were distinct from these other pneumococcal 6B clones but were genetically related to each other {corrected}.

J Infect Dis, 1999 Nov, 180(5), 1569 - 76
Immunity to cross-reactive serotypes induced by pneumococcal conjugate vaccines in infants; Yu X et al.; Infants were immunized with 1 of the 3 experimental pneumococcal conjugate vaccines that contain 6B and 19F but not 6A or 19A serotypes . Their sera were studied for the capacity to opsonize Streptococcus pneumoniae 6A, 6B, 19A, and 19F serotypes and the level of IgG antibody to the 4 serotypes . Significant increases were observed in the number of infants with detectable opsonophagocytic titers with 3 conjugate vaccines for 6B (vaccine) serotype but with only 2 vaccines for 6A (cross-reactive) serotype . Significant increases were observed with 2 conjugate vaccines for 19F serotype but with only 1 vaccine for 19A serotype . Thus, some conjugate vaccines may elicit cross-protection better than others . In addition, correlations between opsonophagocytic titers and IgG antibody levels by ELISA were high for 6B and 19F serotypes but low for 6A and 19A serotypes . Thus, ELISA may be an inadequate surrogate assay of vaccine response for cross-reactive serotypes.

J Bacteriol, 1999 Oct, 181(20), 6552 - 5
Gene disruption studies of penicillin-binding proteins 1a, 1b, and 2a in Streptococcus pneumoniae; Hoskins J et al.; The effects of inactivation of the genes encoding penicillin-binding protein 1a (PBP1a), PBP1b, and PBP2a in Streptococcus pneumoniae were examined . Insertional mutants did not exhibit detectable changes in growth rate or morphology, although a pbp1a pbp1b double-disruption mutant grew more slowly than its parent did . Attempts to generate a pbp1a pbp2a double-disruption mutant failed . The pbp2a mutants, but not the other mutants, were more sensitive to moenomycin, a transglycosylase inhibitor . These observations suggest that individually the pbp1a, pbp1b, and pbp2a genes are dispensable but that either pbp1a or pbp2a is required for growth in vitro . These results also suggest that PBP2a is a functional transglycosylase in S . pneumoniae.

J Neuropathol Exp Neurol, 1999 Oct, 58(10), 1078 - 89
Microglial activation by components of gram-positive and -negative bacteria: distinct and common routes to the induction of ion channels and cytokines; Prinz M et al.; Gram-positive Streptococcus pneumoniae is the major pathogen causing lethal meningitis in adults . We used pneumococcal cell walls (PCW) to investigate microglial consequences of a bacterial challenge and to determine the role of serum in the activation process . PCW caused the characteristic induction of an outwardly rectifying K+ channel (IK+(OR)), together with a concomitant suppression of the constitutively expressed inward rectifier K+ current, and evoked the release of tumor necrosis factor-alpha (TNF alpha), interleukin-6 (IL-6), IL-12, KC, macrophage inflammatory protein (MIP) 1alpha and MIP-2 . Serum presence strongly facilitated the PCW effects, similarly as observed for lipopolysaccharide (LPS) from gram-negative Escherichia coli . The inflammatory cytokine, interferon-gamma (IFNgamma) induced the same electrophysiological changes, but independent of serum . Recombinant LPS binding protein (LBP) could partially replace serum activity in LPS stimulations . In contrast, neither LBP nor an antibody-mediated blockade of the LPS receptor, CD14 had significant influences on PCW-inducible changes . Cell surface interactions and cofactor involvement in microglial activation by gram-positive bacteria are thus distinct from the mechanisms employed by LPS . Moreover, tyrphostin AG126, a protein kinase inhibitor that prevents activation of the mitogen-activated protein kinase, p42MAPK (ERK2), potently blocked the PCW-stimulated cytokine release while having only a limited effect on LPS-inducible cytokines . In contrast, AG126 did not influence IK+(OR) inductions . This indicates that PCW recruits more than 1 intracellular signaling pathway to trigger the various responses and that different bacterial agents signal through both common and individual routes during microglial activation.

Biotechnol Prog, 1999 Oct 1, 15(5), 898 - 910
Structured Model-Based Analysis and Control of the Hyaluronic Acid Fermentation by Streptococcus zooepidemicus: Physiological Implications of Glucose and Complex-Nitrogen-Limited Growth; Cooney MJ et al.; The hyaluronic acid (HA) fermentation by Streptococcus zooepidemicus under anaerobic and aerated conditions in glucose-complex media was well described by a structured, two-compartment model . The two-compartment model framework was found to be robust, easily adaptable, and able to predict the transient consumption of substrates and formation of products . Aerobic culture produced a substantially higher concentration of HA than an equivalent anaerobic culture; however biomass-specific growth rate and yield were lower due to partial inhibition by hydrogen peroxide . The model was then used to investigate the physiological implications of glucose and complex-nitrogen-limited growth on the anaerobic production of hyaluronic acid (HA) . Glucose-limited growth agreed well with model predictions, although the HA molecular weight was lower than expected even though the absolute HA concentration remained unaffected . Heterofermentative growth was also observed for growth rates below 0.1 h(-)(1) . Despite a comparatively lower specific growth rate, the biomass yield was higher; however the metabolic shift did not significantly affect HA production . For complex-nitrogen-limited growth, diauxic growth on complex-nitrogen (yeast extract) was observed and explained by partitioning the array of nitrogen components into two distinct but homogeneous pools . While nitrogen-limited growth was found to increase the HA to biomass yield, like that observed under glucose-limited growth, the resulting HA molecular weight was reduced.

Can Commun Dis Rep, 1999 Sep 1, 25(17), 150 - 1
Pneumococcal vaccines: World Health Organization position paper; Pharmacologic and bacteriologic properties of SCH-27899 (Ziracin) et al.; Department of Pharmacy Practice, College of Pharmacy and Allied Health Professions, Wayne State University, Detroit, Michigan, USASCH-27899 is an investigational antibiotic from the everninomicin family, a group of oligosaccharide antibiotics produced by Micromonospora carbonacea . Information regarding the pharmacology, pharmacodynamics, pharmacokinetics, efficacy, and toxicity of this agent was obtained from a MEDLINE search and a review of abstracts presented at recent scientific meetings . SCH-27899 has in vitro bacteriostatic activity against a wide variety of gram-positive organisms, including highly resistant organisms such as methicillin-resistant Staphylococcus aureus, vancomycin-intermediate-sensitivity S . aureus, Streptococcus pneumoniae (both penicillin-susceptible and -nonsusceptible), and vancomycin-resistant enterococci . In vitro data, animal studies, and preliminary human studies indicate that it is effective and fairly well tolerated . Its place in therapy remains to be determined, and clinical trials continue.

Emerg Infect Dis, 1999 Sep-Oct, 5(5), 688 - 93
Tracking drug-resistant Streptococcus pneumoniae in Oregon: an alternative surveillance method; Chin AE et al.; With the emergence of drug-resistant Streptococcus pneumoniae, community-specific antimicrobial susceptibility patterns have become valuable determinants of empiric therapy for S . pneumoniae infections . Traditionally, these patterns are tracked by active surveillance for invasive disease, collection of isolates, and centralized susceptibility testing . We investigated whether a simpler and less expensive method aggregating existing hospital antibiograms--could provide community-specific antimicrobial susceptibility data . We compared 1996 active surveillance data with antibiogram data from hospital laboratories in Portland, Oregon . Of the 178 S . pneumoniae active surveillance isolates, 153 (86% {95% confidence interval (CI) = 80% to 91%}) were susceptible to penicillin . Of the 1,092 aggregated isolates used by hospitals to generate antibiograms, 921 (84% {95% CI = 82%-87%}) were susceptible to penicillin . With the exception of one hospital's erythromycin susceptibility results, hospital-specific S . pneumoniae susceptibilities to penicillin, cefotaxime, trimethoprim-sulfamethoxazole, and erythromycin from the two methods were statistically comparable . Although yielding fewer data than active surveillance, antibiograms provided accurate, community-specific drug-resistant S . pneumoniae data in Oregon.

J Antimicrob Chemother, 1999 Sep, 44 Suppl A, 19 - 23
Optimal treatment of complicated skin and skin structure infections; Nichols RL; Gram-positive bacteria (e.g . Staphylococcus aureus and Streptococcus pyogenes) are the main cause of skin and skin structure infections (SSSI) . Treatment presents a clinical challenge to the physician, particularly with the increase in multidrug-resistant strains and widespread cross-resistance to antibiotic treatment . Initial treatment of SSSI involves the use of fluoroquinolones or penicillinase-resistant penicillins . If infection is caused by methicillin-resistant staphylococci, therapy with glycopeptides is warranted . However, in the last few years several cases of infection caused by strains of S . aureus with reduced susceptibility to glycopeptides have been reported . Quinupristin/dalfopristin is a new streptogramin that has shown efficacy in the management of multidrug-resistant gram-positive infections . Two major studies suggest that in the treatment of complicated SSSI, the clinical efficacy of quinupristin/dalfopristin is equivalent to that of vancomycin and/or oxacillin and vancomycin and/or cefazolin.

Antonie Van Leeuwenhoek, 1999 May, 75(4), 351 - 9
Adhesion and surface-aggregation of Candida albicans from saliva on acrylic surfaces with adhering bacteria as studied in a parallel plate flow chamber; Millsap KW et al.; Adhesive interactions between Candida albicans and oral bacteria are generally thought to play a crucial role in the microbial colonization of denture acrylic, which may lead to denture stomatitis . This study investigated the influence of saliva on the adhesive interactions between C . albicans and Streptococcus sanguis or Actinomyces naeslundii on denture acrylic . First, bacteria were allowed to adhere to the acrylic surface from a flowing suspension, and subsequently yeasts were flowed over the acrylic surface . The organisms were assayed in the presence or absence of human whole saliva . All experiments were carried out in a parallel plate flow chamber and enumeration was done in situ with an image analysis system . In the absence of adhering bacteria, adhesion of C . albicans from buffer was more extensive than from saliva . However, in the presence of adhering bacteria, yeast adhesion from saliva was increased with respect to adhesion of yeasts from buffer, indicating that specific salivary components constitute a bridge between bacteria and yeasts . In all cases, yeast aggregates consisting of 3 to 5 yeast cells were observed adhering to the surface . A surface physico-chemical analysis of the microbial cell surfaces prior to and after bathing the microorganisms in saliva, suggests that this bridging is mediated by acid-base interactions since all strains show a major increase in electron-donating surface free energy parameters upon bathing in saliva, with no change in their zeta potentials . The surface physico-chemical analysis furthermore suggests that S . sanguis and A . naeslundii may use a different mechanism for adhesive interactions with C . albicans in saliva.

Vestn Otorinolaringol, 1999, (5), 8 - 10
{ENT problems in children with chronic nonspecific pulmonary diseases}; Feigina VM et al.; Combined bronchological and otorhinolaryngological examinations with bacteriological tests were performed in 67 children with chronic nonspecific pulmonary disease (CNSPD) associated with ENT trouble . These patients comprised 69.6% of overall number of children with CNSPD treated by the authors . Bacteriological tests have shown almost absolute identity of microflora from chronic infection foci in the upper and lower airways . Coccal flora predominated, especially pmeumococcal and Streptococcus viridans . The response to treatment was observed both from the lower respiratory tracts and the ENT system . Both ENT and respiratory system benefited from the combined treatment which reduced frequency and duration of the exacerbations . Thus, combined therapy has proved more effective than pulmonological or otorhynolaryngological alone.

J Immunol, 1999 Oct 15, 163(8), 4308 - 14
Cerebral endothelial cells release TNF-alpha after stimulation with cell walls of Streptococcus pneumoniae and regulate inducible nitric oxide synthase and ICAM-1 expression via autocrine loops; Freyer D et al.; TNF-alpha, inducible NO synthase (iNOS), and ICAM-1 are considered to be key proteins in the inflammatory response of most tissues . We tested the hypothesis that cell walls of Streptococcus pneumoniae (PCW), the most common cause of adult bacterial meningitis, induce TNF-alpha, iNOS, and ICAM-1 expression in rat primary brain microvascular endothelial cell cultures . We detected TNF-alpha mRNA by RT-PCR already 1 h after stimulation with PCW, while TNF-alpha protein peaked at 4 h (9.4 +/- 3.6 vs 0.1 +/- 0.1 pg/microgram protein) . PCW induced iNOS mRNA 2 h after stimulation, followed by an increase of the NO degradation product nitrite (18.1 +/- 4 vs 5.8 +/- 1.8 at 12 h; 18.1 +/- 4 vs 5.8 +/- 1.8 pmol/microgram protein at 72 h) . The addition of TNF-alpha Ab significantly reduced nitrite production to 62.2 +/- 14.4% compared with PCW-stimulated brain microvascular endothelial cells (100%) . PCW induced the expression of ICAM-1 (measured by FACS), which was completely blocked by TNF-alpha Ab (142 +/- 18.6 vs 97.5 +/- 12.4%; 100% unstimulated brain microvascular endothelial cells) . Cerebral endothelial cells express TNF-alpha mRNA as well as iNOS mRNA and release the bioactive proteins in response to PCW . PCW-induced NO production is mediated in part by an autocrine pathway involving TNF-alpha, whereas ICAM-1 expression is completely mediated by this autocrine loop . By these mechanisms, cerebral endothelial cells may regulate critical steps in inflammatory blood-brain-barrier disruption of bacterial meningitis.

Clin Ther, 1999 Sep, 21(9), 1525 - 32
Comparison of cefdinir and penicillin for the treatment of pediatric streptococcal pharyngitis; Nemeth MA et al.; This multicenter, randomized, controlled, investigator-masked study was performed to assess the efficacy and tolerability of cefdinir for the treatment of streptococcal pharyngitis . Children aged 1 through 12 years with signs and symptoms of pharyngitis and a positive result on a rapid screening test for Streptococcus pyogenes were randomly assigned to receive cefdinir 14 mg/kg QD, cefdinir 7 mg/kg BID, or penicillin V 10 mg/kg 4 times daily for 10 days . Seven hundred ninety-two patients were enrolled, and 682 were clinically and microbiologically assessable . All treatment groups had similar demographic characteristics (-50.0% male, predominantly white, median age 7 years) . The eradication rates of S pyogenes, determined 4 to 9 days after completion of therapy, were 94.3% in the cefdinir QD group, 94.3% in the cefdinir BID group, and 70.0% in the penicillin V group (95% confidence interval {CI} 17.6%-30.9%, P < 0.001 for cefdinir QD vs penicillin; CI 17.5%-30.9%, P < 0.001 for cefdinir BID vs penicillin) . Clinical cure rates were 97.4%, 96.0%, and 86.3% for the cefdinir QD, cefdinir BID, and penicillin groups, respectively (CI 6.1%-15.9%, P = 0.001 for cefdinir QD vs penicillin; CI 4.6%-14.8%, P = 0.001 for cefdinir BID vs penicillin) . Adverse reactions occurred in 8.3%, 8.7%, and 7.6% of cefdinir QD, cefdinir BID, and penicillin patients, respectively (P = NS) . Treatment with cefdinir, either QD or BID, was associated with higher eradication rates of S pyogenes and higher clinical cure rates . Both cefdinir and penicillin were well tolerated . Three patients, 1 receiving cefdinir BID and 2 receiving penicillin, discontinued the study drug because of adverse reactions.

Appl Environ Microbiol, 1999 Oct, 65(10), 4346 - 50
Cloning and analysis of the L-lactate utilization genes from Streptococcus iniae; Gibello A et al.; The presence of lactate oxidase was examined in eight Streptococcus species and some related species of bacteria . A clone (pGR002) was isolated from a genomic library of Streptococcus iniae generated in Escherichia coli, containing a DNA fragment spanning two genes designated lctO and lctP . We show that these genes are likely to be involved in the L-lactic acid aerobic metabolism of this organism . This DNA fragment has been sequenced and characterized . A comparison of the deduced amino acid sequence of LctP protein demonstrated that the protein had significant homology with the L-lactate permeases of other bacteria . The amino acid sequence of the LctO protein of S . iniae also showed a strong homology to L-lactate oxidase from Aerococcus viridans and some NAD-independent lactate dehydrogenases, all belonging to the family of flavin mononucleotide-dependent alpha-hydroxyacid-oxidizing enzymes . Biochemical assays of the gene products confirm the identity of the genes from the isolated DNA fragment and reveal a possible role for the lactate oxidase from S . iniae . This lactate oxidase is discussed in relation to the growth of the organism in response to carbon source availability.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2510 - 2
Patterns of macrolide resistance determinants among community-acquired Streptococcus pneumoniae isolates over a 5-year period of decreased macrolide susceptibility rates; Oster P et al.; Erythromycin resistance rates were found to be increased, from 7.1 in 1993 to 32.8% in 1997, among community-acquired Streptococcus pneumoniae isolates from the Siena area of central Italy . Most of the erythromycin-resistant isolates carried ermAM determinants and were also resistant to josamycin and clindamycin, whereas a minority (5.8%) carried mefA determinants and remained susceptible to the latter drugs.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2504 - 9
Prevalence of antimicrobial resistance in respiratory tract isolates of Streptococcus pneumoniae: results of a Canadian national surveillance study . The Canadian Respiratory Infection Study Group; Zhanel GG et al.; From October 1997 to November 1998, 1,180 respiratory tract isolates of Streptococcus pneumoniae were collected from 18 medical centers in 9 of the 10 Canadian provinces . Penicillin-intermediate and -resistant isolates occurred at rates of 14.8 and 6.4%, respectively, and these rates varied considerably by geographic region . Trimethoprim-sulfamethoxazole, tetracycline, and macrolide rates of nonsusceptibility were 12.2, 10.6, and 8.0 to 9.3%, respectively . The most potent agents studied were newer fluoroquinolones.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2484 - 92
Development of a new experimental model of penicillin-resistant Streptococcus pneumoniae pneumonia and amoxicillin treatment by reproducing human pharmacokinetics; Piroth L et al.; The increase of penicillin-resistant Streptococcus pneumoniae (PRSP) pneumonia results in a greater risk of antibiotic treatment failure . In vitro data are not sufficient predictors of clinical efficacy, and animal models may be insufficiently contributive, since they often use immunocompromised animals and do not always respect the human pharmacokinetics of antibiotics . We developed an experimental PRSP pneumonia model in immunocompetent rabbits, by using intrabronchial instillation of PRSP (MIC = 4 mg/liter), without any adjuvant . This reproducible model was used to assess amoxicillin efficacy by reproducing human serum pharmacokinetics following 1-g oral or intravenous administrations of amoxicillin every 8 h . Evaluation was performed by using clinical, CT scan, macroscopic, histopathologic, and microbiological criteria . Experimental pneumonia in untreated rabbits was similar to untreated severe human bacteremic untreated pneumonia; in both rabbits and humans, (i) cumulative survival was close to 50%, (ii) red or gray lung congestion and pleuritis were observed, and (iii) lung and spleen concentrations reached 5 and 4 log(10) CFU/g . A 48-h treatment resulted in a significant bacterial clearance in the lungs (1.53 versus 5.07 log(10) CFU/ml, P < 0.001) and spleen (1.00 versus 4.40 log(10) CFU/ml, P < 10(-6)) and a significant decrease in mortality (0% versus 50%, P = 0.02) in treated versus untreated rabbits . No difference was observed on macroscopic and histopathologic lesions between treated and untreated rabbits (P = 0.36 and 0.78, respectively) . Similar results were obtained by using a fully penicillin-susceptible S . pneumoniae strain (MIC = 0.01 mg/liter) . Our findings suggest that (i) this new model can be contributive in the evaluation of antibacterial agents and (ii) 1 g of amoxicillin three times a day may be sufficient to treat PRSP pneumonia in immunocompetent humans.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2372 - 5
Killing activities of trovafloxacin alone and in combination with beta-lactam agents, rifampin, or vancomycin against Streptococcus pneumoniae isolates with various susceptibilities to extended-spectrum cephalosporins at concentrations clinically achievable in cerebrospinal fluid; Fitoussi F et al.; The killing activities of trovafloxacin alone and in combination with beta-lactam agents (extended-spectrum cephalosporins, meropenem), rifampin, or vancomycin were evaluated against 20 genotypically characterized Streptococcus pneumoniae isolates for which amoxicillin MICs were >/=4 microg/ml (cefotaxime MICs, >/=4 microg/ml for six strains) at concentrations clinically achievable in cerebrospinal fluid . At 6 h the mean killing activity of trovafloxacin alone (range, 2.6 to 2.9 log(10) CFU/ml) did not vary significantly according to the susceptibility of the strains to beta-lactam agents . The activities of trovafloxacin or vancomycin added to the beta-lactam agents and the combination trovafloxacin-vancomycin were additive or indifferent . Against the ceftriaxone-resistant isolates, the killing activity of the combination of a beta-lactam agent and trovafloxacin did not differ significantly from that of a beta-lactam agent and vancomycin.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2361 - 5
Molecular basis of rifampin resistance in Streptococcus pneumoniae; Padayachee T et al.; Rifampin resistance among South African clinical isolates of Streptococcus pneumoniae was shown to be due to missense mutations within the rpoB gene . Sequence analysis of 24 rifampin-resistant isolates revealed the presence of mutations within cluster I as well as novel mutations in an area designated pneumococcus cluster III . Of the 24 isolates characterized, only 1 resistant isolate did not contain any mutations in the regions sequenced . Either the cluster I or the cluster III mutations separately conferred MICs of 32 to 128 microg/ml . Clinical isolate 55, for which the MIC was 256 microg/ml, was noted to contain 9 of the 10 mutations identified, which included the cluster I and cluster III mutations . As in Escherichia coli, it is possible that cluster I (amino acids 406 to 434) and cluster III (amino acids 523 to 600) of S . pneumoniae interact to form part of the antibiotic binding site, thus accounting for the very high MIC observed for isolate 55 . PCR products containing cluster I or cluster III mutations were able to transform rifampin-susceptible S . pneumoniae to resistance . Although many of the isolates studied displayed identical sequences, pulsed-field gel electrophoresis analysis revealed that the isolates were not of clonal origin.

Antimicrob Agents Chemother, 1999 Oct, 43(10), 2345 - 9
Penetration of moxifloxacin into peripheral compartments in humans; Muller M et al.; To characterize the penetration of moxifloxacin (BAY 12-8039) into peripheral target sites, the present study aimed at measuring unbound moxifloxacin concentrations in the interstitial space fluid by means of microdialysis, an innovative clinical sampling technique . In addition, moxifloxacin concentrations were measured in cantharides-induced skin blisters, saliva, and capillary plasma and compared to total- and free-drug concentrations in venous plasma . For this purpose, 12 healthy volunteers received moxifloxacin in an open randomized crossover fashion either as a single oral dose of 400 mg or as a single intravenous infusion of 400 mg over 60 min . An almost-complete equilibration of the free unbound plasma fraction of moxifloxacin with the interstitial space fluid was observed, with mean area under the concentration-time curve (AUC)(interstitial fluid)/AUC(total-plasma) ratios ranging from 0.38 to 0.55 and mean AUC(interstitial fluid)/AUC(free-plasma) ratios ranging from 0.81 to 0.86 . The skin blister concentration/plasma concentration ratio reached values above 1.5 after 24 h, indicating a preferential penetration of moxifloxacin into inflamed lesions . The moxifloxacin concentrations in saliva and capillary blood were similar to the corresponding levels in plasma . Our data show that moxifloxacin concentrations attained in the interstitial space fluid in humans and in skin blister fluid following single doses of 400 mg exceed the values for the MIC at which 90% of isolates are inhibited for most clinically relevant bacterial strains, notably including penicillin-resistant Streptococcus pneumoniae . These findings support the use of moxifloxacin for the treatment of soft tissue and respiratory tract infections in humans.

Otolaryngol Head Neck Surg, 1999 Oct, 121(4), 381 - 7
Treatment of lymphangiomas in children: an update of Picibanil (OK-432) sclerotherapy; Greinwald JH Jr et al.; Picibanil (OK-432) is a sclerosing agent derived from a low-virulence strain of Streptococcus pyogenes that induces regression of macrocystic lymphangiomas . This report describes a prospective, nonrandomized trial to evaluate the efficacy of Picibanil in the treatment of 13 affected children ranging in age from 1 to 94 months . On average, 4.1 fluoroscopically guided intracystic injections were performed per child, with an average total dose of 0.56 mg of Picibanil . As judged by physical examination and radiographic studies, 5 children (42%) showed a complete or substantial response, and 2 children (16%) showed an intermediate response . No response was seen in 5 children (42%), 2 of whom had massive craniofacial lymphangioma . Factors that contribute to failure with Picibanil sclerotherapy are the presence of a significant microcystic component to the lesion, massive craniofacial involvement, and previous surgical resection . Macrocystic lymphangiomas of the infratemporal fossa or cervical area have the best response to therapy.

Biochemistry, 1999 Sep 28, 38(39), 12950 - 8
Evidence for the chemical activation of essential cys-302 upon cofactor binding to nonphosphorylating glyceraldehyde 3-phosphate dehydrogenase from Streptococcus mutans; Marchal S et al.; Nonphosphorylating glyceraldehyde 3-phosphate dehydrogenase (GAPN) from Streptococcus mutans which catalyzes the irreversible oxidation of D-glyceraldehyde-3 phosphate (D-G3P) into 3-phosphoglycerate (3-PGA) in the presence of NADP belongs to the aldehyde dehydrogenase (ALDH) superfamily . Oxidation of D-G3P into 3-PGA by GAPN involves the formation of a covalent enzyme intermediate via the nucleophilic attack of the invariant Cys-302 . Titration of Cys-302 in the apo-enzyme by two different kinetic probes, iodoacetamide and 2,2'-dipyridyl disulfide, shows a pK(app) of 8.5 and a chemical reactivity surprisingly low compared to a reactive and accessible thiolate . Binding of NADP causes a strong increase of the reactivity of Cys-302-which is time dependent-with a pK(app) shift from 8.5 to 6.1 . Concomitant with the increase in the Cys-302 reactivity, an additional protein fluorescence quenching is observed . These data suggest that cofactor binding induces at least a local conformational rearrangement within the active site . The efficiency of the rearrangement depends on the structure of the cofactors and on the protonation of an amino acid with a pK(app)( )()of 5.7 . The rate of the rearrangement also strongly increases when temperature decreases . The data on the conformational rearrangement also reveal an amino acid with a pK(app) of 7.6 whose deprotonation increases the reactivity of the thiolate of Cys-302 by a 3-fold factor . The nature of the amino acid involved-which should be located close to Cys-302 in the holo-active form-is likely the invariant Glu-268 . Changing Glu-268 into Ala or Cys-302 into Ala leads to mutants in which the rearrangement is only efficient in the presence of saturating concentrations of both NADP and G3P . The structural aspects of the conformational rearrangement occurring during the catalytic process in the wild-type GAPN should include at least reorientation of both Cys-302 and Glu-268 side chains and repositioning of the nicotinamide ring of the cofactor to permit the chemical activation of Cys-302 and the formation of an efficient ternary complex . Thus, it is likely that the conformation of the active site in the reported X-ray structures of ALDHs determined so far in the presence of cofactor, in which the side chains of Cys-302 and Glu-268 are 6.7 A apart from each other, does not represent the biological active form.

Acta Paediatr, 1999 Aug, 88(8), 874 - 9
Role of postnatal penicillin prophylaxis in prevention of neonatal group B streptococcus infection; Patel DM et al.; This prospective study was designed to identify the role of postnatal penicillin prophylaxis in the prevention of neonatal group B streptococcus (GBS) infection . We studied 10 998 infants . Of these, 5389 were in the penicillin prophylaxis group (PP) and 5609 infants did not receive penicillin prophylaxis (NPP) . Infants were allocated to treatment by month of birth, alternating 3-mo blocks or 2-mo blocks to the two groups after the first block was randomly assigned . The use of PP reduced the incidence of clinical sepsis (1.7% PP versus 2.5% NPP, p < 0.01), GBS infection (0.4% PP versus 0.9% NPP, p < 0.001) and deaths from sepsis (0.1% PP versus 0.3% NPP, p < 0.05) . We conclude that the routine use of postnatal penicillin prophylaxis appears to be effective in reducing the incidence of clinical sepsis and death from sepsis in neonates.

Res Vet Sci, 1999 Oct, 67(2), 131 - 5
The role of hyaluronic acid capsular material of Streptococcus equi subsp . zooepidemicus in mediating adherence to HeLa cells and in resisting phagocytosis; Wibawan IW et al.; Hyaluronic acid is thought to be one of the critical virulence factors of Streptococcus equi subsp . zooepidemicus . The present study was designed to study the role of hyaluronic acid capsular material in mediating adherence and to resist the phagocytosis of the host's immune defence . The studies were performed with two encapsulated S . equi subsp . zooepidemicus and two unencapsulated phase variants . The bacteria had been previously isolated from diseased pigs and monkeys in Indonesia . The presence of capsular material was determined using the hyaluronic acid decapsulation test and by electron microscopic studies . Both encapsulated bacteria showed mucoid colonies after cultivation on blood agar, grew with diffuse colonies in soft agar media and reacted negatively in the salt aggregation test . The unencapsulated bacteria grew with small colonies on blood agar, formed compact colonies in soft agar media and reacted positively in the salt aggregation test . Adherence and phagocytosis studies revealed that the encapsulated bacteria adhered significantly more to HeLa cells and were less phagocytosed by murine macrophages compared to unencapsulated bacteria . Pretreatment of the HeLa cells using hyaluronic acid or pretreatment of the bacteria by hyaluronidase decreased the adherence value of encapsulated bacteria . Pretreatment of bacteria with pronase had no effect . The presented results strongly indicate that the hyaluronic acid capsular material contributes to adherence properties of S . equi subsp . zooepidemicus and might help the bacteria to resist phagocytosis by macrophages .

Semin Respir Infect, 1999 Sep, 14(3), 276 - 84
Treatment of pneumococcal pneumonia; Pallares R; The emergence of Streptococcus pneumoniae strains with resistance to penicillin, macrolide, and other drugs has made the treatment of pneumococcal infections more complicated . Although resistance to penicillin has had a profound impact on the outcome of meningitis, it has had little impact on the mortality from pneumococcal pneumonia because the serum and pulmonary levels achieved with penicillin (or related drugs) are several times higher than the minimal inhibitory concentration of the strains . Thus, based on current levels of resistance to penicillin and cephalosporin, most patients with mild/moderate pneumococcal pneumonia may respond to oral amoxicillin, and most with severe pneumonia may be successfully treated with intravenous ceftriaxone, cefotaxime, or amoxicillin-clavulanic acid . It is of concern that patients infected with erythromycin-resistant pneumococci may not respond to therapy with a macrolide . In our opinion, except for well-selected patients, imipenem and vancomycin should not be widely used for the treatment of pneumococcal pneumonia . Some new drugs such as the new quinolones may play an important role in the management of pneumonia in the near future.

Semin Respir Infect, 1999 Sep, 14(3), 269 - 75
The role of the molecular laboratory in the investigation of Streptococcus pneumoniae infections; Gillespie SH; The importance of infections with Streptococcus pneumoniae is being increasingly recognized . This has been emphasised by the emergence and international dissemination of penicillin-resistant strains . These factors challenge modern microbiologists to use molecular tools to speed the process of the diagnosis of S pneumoniae at each of the stages: rapid diagnosis, culture identification, and typing . The polymerase chain reaction (PCR) has been used to amplify a number of different targets for primary diagnosis of pneumonia, meningitis, otitis media, and bacteraemia . This may provide a rapid diagnosis in patients who have been partially treated with antibiotics and increase the diagnostic yield in clinical trials of antimicrobial agents and new vaccines . A new development is the use of PCR to rapidly determine penicillin susceptibility . Several different experimental protocols are reviewed . In the past serotyping using the capsule swelling, or Quellung reaction was the only typing method available . Recent insight into epidemiology and population genetics of S pneumoniae has shown that this technique is inadequate to study the transmission of this organism . New molecular typing techniques have been developed including Field version gel electrophoresis, ribotyping, restriction fragment end labeling, BOX PCR, and random amplification of polymorphic DNA . As these methods become available to clinicians, they will gain more understanding of the way in which this organism interacts with human populations.

Semin Respir Infect, 1999 Sep, 14(3), 255 - 68
Molecular mechanisms of resistance to commonly used non-betalactam drugs in Streptococcus pneumoniae; Widdowson CA et al.; This article reviews the molecular mechanisms of resistance to fluoroquinolones, erythromycin, chloramphenicol, tetracycline, and trimethoprim-sulfamethoxazole in Streptococcus pneumoniae . Resistance to fluoroquinolones primarily involves mutations in the DNA gyrase gene, gyrA, and in the topoisomerase IV genes, parC and parE, although in vitro studies have indicated that some strains may use an efflux mechanism for resistance to certain fluoroquinolones . Ciprofloxacin resistance results from initial and necessary mutations in ParC leading to low-level resistance and subsequent mutations in GyrA leading to high-level resistance . Sparfloxacin resistance results from initial mutations in GyrA, with ParC mutations occurring subsequently . A single amino acid substitution in ParE has also been associated with low-level resistance in S pneumoniae . Two mechanisms have been described for resistance to erythromycin . Coresistance to macrolides, lincosamides, and streptogramin B type antibiotics is a result of modification of the ribosome through methylation of an adenine residue in domain V of the 23S rRNA . This methylation is encoded by the methylase gene, ermAM . Resistance only to 14-and 15-membered macrolides is a result of efflux of the antibiotic from the cell, encoded by the gene, mefE, in S pneumoniae, and appears to be rapidly emerging as the predominant mechanism of resistance to erythromycin in many countries . The production of chloramphenicol acetyltransferase, an enzyme capable of catalyzing the conversion of chloramphenicol to its nonfunctional 1-acetoxy, 3-acetoxy, and 1,3-diacetoxy derivatives, leads to chloramphenicol resistance in S pneumoniae . Chloramphenicol acetyltransferase is encoded by a cat gene identical to the cat gene from the Staphylococcus aureus plasmid, pC194 . Tetracycline resistance occurs through ribosomal protection encoded by the genes tet(M) and tet(O) . It is possible that the Tet(M) and Tet(O) proteins cause tetracycline to be released from the ribosome, although the precise mechanism remains unclear . Resistance to trimethoprim is mediated through a single amino acid substitution in the chromosomal dihydrofolate reductase gene of S pneumoniae, which is thought to disrupt the bond with trimethoprim without affecting the action of the dihydrofolate reductase . Sulphonamide resistance appears to result from repetitions of one or two amino acids in the chromosomal dihydropteroate synthase . Although resistance exists to nearly all antimicrobial agents used in the treatment of S pneumoniae infections, ongoing research into new or alternative therapies is encouraging.

Semin Respir Infect, 1999 Sep, 14(3), 243 - 54
The epidemiology of penicillin resistance in Streptococcus pneumoniae; Forward KR; Pneumococci are not intrinsically resistant penicillin or other commonly used antibiotics . Penicillin-resistant strains were not encountered until 1965 when two strains were identified in Boston . At that time, the resistance was of a minor degree and its significance was not recognized by the authors . In 1971, resistant strains were encountered in New Guinea and, by the late 1970s, penicillin-resistant pneumococci had spread worldwide . By the early 1980s, areas where more than 10% of isolates were found to be penicillin resistant included Israel, Poland, Spain, South Africa, New Guinea, and the United States from New Mexico to Alaska . In this decade a number of countries including South Korea, Hungary, and Spain have reported dramatic increases in penicillin resistance . Penicillin resistance, once acquired by a virulent pneumococcal clone, has the ability to spread from country to country and to other continents in a relatively short time . Coincident with the increasing penicillin resistance has been the development of resistance to a wide variety of other antibiotics, including other cephalosporins, macrolides, trimethoprim-sulfamethoxazole, tetracycline, and chloramphenicol . Some strains are so highly resistant as to significantly impair our ability to treat patients with meningitis and to choose an appropriate oral agent for the treatment of pneumococcal otitis media.

Semin Respir Infect, 1999 Sep, 14(3), 237 - 42
Pneumococcal infections in HIV-infected adults; Schneider RF et al.; Bacterial pneumonia, specifically pneumococcal infection, is a frequent cause of morbidity and mortality in persons infected with human immunodeficiency virus (HIV) . It causes morbidity directly and possibly progression of HIV infection . The clinical presentation and response to therapy are usually similar to that of patients without HIV infection, although radiographic presentations may be atypical . There is a higher incidence of invasive disease and extrapulmonary disease, and mortality may be increased in HIV-infected patients . HIV infection impairs the host response to pneumococcus in a variety of ways . Colonization with Streptococcus pneumoniae may be prolonged for reasons that are incompletely understood . Concern about the rising prevalence of resistant pneumococcal strains is increasing, but the clinical relevance is uncertain . At least 90% of the strains that cause invasive disease are present in the 23-valent pneumococcal vaccine . The response to vaccination declines as immunodeficiency progresses; however, the potential benefit to responders is great and the risk is minimal . Therefore, this vaccine is recommended for all HIV-infected persons.

Semin Respir Infect, 1999 Sep, 14(3), 227 - 36
Pneumococcal pneumonia: epidemiology and clinical features; Marrie TJ; Pneumoccal pneumonia is a common illness; the highest incidence occurs at the extremes of age . The rate of pneumococcal bacteremic pneumonia is higher in blacks than in whites and 41 times higher in those with human immunodeficiency virus (HIV) infection than in individuals of the same age who are not HIV infected . Risk factors for pneumococcal pneumonia include dementia, seizure disorders, cigarette smoking, congestive heart failure, cerebrovascular disease, institutionalization, and chronic obstructive pulmonary disease . Outbreaks of pneumococcal pneumonia occur in situations of overcrowding such as in jails or in shelters for the homeless . Streptococcus pneumoniae is the most common cause of community acquired pneumonia requiring hospitalization, accounting for up to 50% of all such cases . The mortality rate from this infection varies considerably in reported studies ranging from 7% to 36% . Bacteremic pneumococcal pneumonia often has a complicated course . Respiratory failure, meningitis, pleural effusion, and empyema are the most common complications . The radiographic manifestations of pneumococcal pneumonia vary, but in general lobar consolidation is more likely to be associated with bacteremia . Cavitation is unusual.

Semin Respir Infect, 1999 Sep, 14(3), 198 - 208
A brief history of the pneumococcus in biomedical research; Watson DA et al.; Because of its importance in human disease, Streptococcus pneumoniae has been the subject of intensive study at both the clinical and basic scientific levels for more than a century . In a number of instances, important advances in basic biology have resulted . Among these are the development of Gram's stain for identification of bacteria in patient specimens, investigations of the role of the bacterial capsule in resistance to phagocytosis by cells of the host immune system, demonstration that molecules other than proteins are capable of eliciting host humoral immune responses, development of safe and effective vaccines composed of isolated bacterial exopolysaccharides, confirmation of the efficacy of penicillin against serious gram-positive infections, and perhaps most important confirmation that DNA alone encodes genetic information.

FEMS Microbiol Lett, 1999 Sep 15, 178(2), 265 - 70
Rapid PCR test for Streptococcus suis serotype 7; Smith HE et al.; Recent epidemiological studies on Streptococcus suis infections in pigs indicated that, besides serotypes 1, 2 and 9, serotype 7 is also frequently associated with diseased animals . For the latter serotype, however, no rapid and sensitive diagnostic methods are available . This hampers prevention and control programs . Here, we describe the development of a type-specific PCR test for the rapid and sensitive detection of S . suis serotype 7 . The test is based on DNA sequences of capsular (cps) genes specific for serotype 7 . These sequences were identified by cross-hybridization of several individual cps genes with the chromosomal DNAs of 35 different S . suis serotypes.

J Nutr, 1999 Oct, 129(10), 1836 - 41
Bovine milk antibodies against cell surface protein antigen PAc-glucosyltransferase fusion protein suppress cell adhesion and alter glucan synthesis of Streptococcus mutans; Oho T et al.; Cell surface protein antigen (PAc) and glucosyltransferases (GTF) produced by Streptococcus mutans are considered major colonization factors of the organism, and the inhibition of these factors is thought to prevent dental caries . In this study, 8-mo-old pregnant Holstein cows were immunized with fusion protein PAcA-GB, a fusion of the saliva-binding alanine-rich region (PAcA) of PAc with the glucan binding (GB) domain of GTF-I, an enzyme catalyzing the synthesis of water-insoluble glucan from sucrose . High titers of immunoglobulin antibodies specific for the fusion protein were found in normal milk after reimmunization, and they persisted for approximately 3 mo . The immunoglobulin G (IgG) antibodies against PAcA-GB were purified from immunized milk . The antibodies significantly inhibited the adhesion of S . mutans cells to saliva-coated hydroxyapatite beads . IgG antibodies purified from immunized milk also inhibited total glucan synthesis by cell-associated GTF preparation and GTF-I from S . mutans . The immunized milk may be useful as a means of passive immunization for the prevention of dental caries in humans.

J Bacteriol, 1999 Oct, 181(19), 6214 - 9
Characterization of the type 8 capsular gene cluster of Streptococcus pneumoniae; Munoz R et al.; The complete nucleotide sequence of the capsular gene cluster (cap8) responsible for the biosynthesis of the capsular polysaccharide of Streptococcus pneumoniae type 8 has been determined . The cap8 gene cluster, located between the genes dexB and aliA, is composed of 12 open reading frames . A 14.7-kb DNA fragment embracing the cap8 genes was sufficient to transform an unencapsulated type 3 S . pneumoniae strain to a strain with the type 8 capsule . A possible scenario for the evolution of pneumococcal types 2 and 8 is outlined.

J Bacteriol, 1999 Oct, 181(19), 6019 - 27
Identification of pel, a Streptococcus pyogenes locus that affects both surface and secreted proteins; Li Z et al.; A Tn917 insertion mutant of an M49 serotype, opacity factor-positive Streptococcus pyogenes, was isolated . It had the following phenotypes: decreased beta-hemolysis mediated by streptolysin S, reduction in the activity of a secreted cysteine protease and streptokinase, and an altered immunoglobulin and fibrinogen-binding phenotype . The site of insertion of Tn917 into the chromosome and the surrounding sequence, the pel region (pleiotropic effect locus), was determined . Phage A25 transduction confirmed that the pleiotropic changes in phenotype could be cotransduced with Tn917 . The pel region was cloned and sequenced, and the transposon was found to be inserted upstream of a single open reading frame which led to a failure to transcribe a 500-base mRNA . The loss of this transcript decreased the transcription of emm and speB genes and reduced the secretion of streptokinase . Enhanced Pel expression from a nisin-inducible plasmid resulted in increased message levels for emm in a wild-type organism . Characterization of the pel mutant provides evidence for the coordinated regulation of secreted and surface proteins and suggests the existence of a new global regulatory factor in S . pyogenes.

J Biomed Mater Res, 1999 Dec 15, 47(4), 516 - 22
Characterization and inhibitory effect of antibacterial dental resin composites incorporating silver-supported materials; Yoshida K et al.; Resin composites with antibacterial activity may be useful for preventing the secondary caries frequently seen around restorations . The purposes of this study were to investigate antibacterial light-activated dental resin composites incorporating each of two silver-supported antibacterial materials and evaluate their long-lasting inhibitory effect against Streptococcus mutans . Two types of silver-supported antibacterial materials, Novaron (N) and Amenitop (AM) were used . These antibacterial materials were incorporated into TEGDMA-UDMA-based light-activated resin composites, and the antibacterial activities and mechanical properties of these composites, and also the release of silver ions, were examined . Two silver-supported antibacterial materials inhibited the growth of the major oral pathogen S . mutans . The minimum inhibitory concentration in suspensions of N and AM against S . mutans was 40 microg/mL and 30 microg/mL, respectively . Composites incorporating 5 wt % (N-5) or more of Novaron and 7 wt % (AM-7) or more of Amenitop inhibited the growth of S . mutans after immersion in water for 6 months . There was no or extremely little release of silver ions from the N-5 and AM-7 composites after 1 day or after 6 months of immersion in water . No significant difference in either compressive or flexural strength was observed between the control and the N-5 composites after 1 day or after 6 months of storage in water . However, for the AM-5 composite, there was a significant difference in both strength parameters between the two immersion periods . These results indicate that a light-activated dental resin composite incorporating silver-supported antibacterial material such as Novaron may be useful clinically because of its long-lasting inhibitory effect against S . mutans and its favorable mechanical properties .

Infect Immun, 1999 Oct, 67(10), 5495 - 9
Growth-phase-dependent expression of virulence factors in an M1T1 clinical isolate of Streptococcus pyogenes; Unnikrishnan M et al.; The effect of growth phase on expression of virulence-associated factors was studied by Northern hybridization in an M1T1 clinical isolate of Streptococcus pyogenes . Expression of M protein, C5a peptidase, and capsule was maximal in the exponential phase of growth, while streptococcal pyrogenic exotoxins A and B and mitogenic factor were maximally expressed in later phases of growth.

Infect Immun, 1999 Oct, 67(10), 5298 - 305
A two-component regulatory system, CsrR-CsrS, represses expression of three Streptococcus pyogenes virulence factors, hyaluronic acid capsule, streptolysin S, and pyrogenic exotoxin B; Heath A et al.; Certain Tn916 insertions in the chromosome of an M1-type, nonmucoid Streptococcus pyogenes isolate (MGAS166) were previously shown to result in stable mucoidy with increased expression of the capsular synthetic genes . The transposon insertions in these strains are directly upstream of an apparent operon encoding a two-component regulatory system, designated csrR-csrS . Compared with MGAS166, these mucoid mutants are more hemolytic and cause significantly more tissue damage in a murine model of skin infection . To extend these observations, we constructed an in-frame deletion in the gene encoding the response regulator, csrR, and we evaluated the expression of other known S . pyogenes virulence factors . We discovered that csrR mutants have enhanced transcription of sagA, a gene associated with streptolysin S (SLS) and speB, the gene encoding pyrogenic exotoxin B (SpeB) . The mutants also express substantially higher SLS activity and SpeB antigen in late-exponential-phase cultures . There is no change in expression of emm, scpA, sic, or cpa (genes encoding other S . pyogenes virulence factors) . CsrR- strains but not the wild-type parental strain produce necrotizing lesions in a mouse model of subcutaneous infection . A double mutant with deletions in both csrR and the capsular synthesis genes caused fewer and smaller necrotic skin lesions than the csrR mutants . However, this nonmucoid csrR strain was more likely than the wild type to yield necrotic lesions, suggesting that mucoidy contributes to virulence in this model of infection but that there are other csrR-regulated factors involved in the production of necrotic lesions.

Infect Immun, 1999 Oct, 67(10), 5206 - 14
Streptococcus parasanguis pepO encodes an endopeptidase with structure and activity similar to those of enzymes that modulate peptide receptor signaling in eukaryotic cells; Froeliger EH et al.; Studies in our laboratory have identified two fimbria-associated adhesins, FimA and Fap1, of Streptococcus parasanguis FW213 . In this study, we isolated and sequenced DNA fragments linked to fimA to determine if they contained additional factors associated with adherence, virulence, or survival in the host . An open reading frame just upstream and divergently transcribed from the fimA operon was identified and named pepO . Northern hybridization indicated that pepO is transcribed as a monocistronic message . pepO encodes a predicted 631-amino-acid protein with a molecular mass of approximately 70.6 kDa . PepO contains the essential motif HEXXH, typical of many zinc-dependent metalloproteases and metallopeptidases . PepO has significant sequence identity to mammalian metallopeptidases, including endothelin-converting enzyme, which converts a potent vasoconstrictor into its active form, and neutral endopeptidase (NEP), which is involved in terminating the activity of opioid peptides . The opioid peptide metenkephalin is a natural substrate of NEP . Cell extracts of FW213 cleaved metenkephalin at the same site as does NEP, while an extract from an insertionally inactivated pepO mutant did not . These results indicate that FW213 pepO encodes an enzyme with activity similar to that of known mammalian endopeptidases . Phylogenetic analysis of PepO and its homologues suggests lateral genetic exchange between bacteria and eukaryotes.

BMJ, 1999 Sep 25, 319(7213), 824 - 7
Systematic review of near patient test evaluations in primary care; Delaney BC et al.; OBJECTIVE: To identify and qualitatively synthesise the findings from all studies that have examined the performance and effect of near patient tests in the primary care setting . DESIGN: Systematic review of published and unpublished research 1986-99 . Main outcome measures: Test performance characteristics, measures of effect on clinical practice or patient outcome . RESULTS: 101 relevant publications were identified . The general quality of these papers was low, and consequently only 32 papers were assessed in detail . Although these papers gave some indication of the value of near patient testing in areas such as anticoagulation monitoring and group A beta haemolytic streptococcus testing, the research raised many more questions than it answered . Almost no reports were found of unbiased assessment of the effect of near patient tests in primary care on patient outcomes, organisational outcomes, or cost . CONCLUSIONS: Available research provides little evidence to guide the expansion of use of near patient testing in primary care . Further research is needed in areas of clinical practice where near patient tests might be most beneficial.

Electrophoresis, 1999 Aug, 20(11), 2259 - 68
A proteomic analysis of erythromycin resistance in Streptococcus pneumoniae; Cash P et al.; Streptococcus pneumoniae is a significant human pathogen which is an important cause of pneumonia and bacteraemia . Over the past few years the incidence of antibiotic resistance among clinical isolates of S . pneumoniae has increased . Penicillin resistance is now widespread and the frequency of isolates that are resistant to erythromycin has risen . Erythromycin resistance in S . pneumoniae follows two basic patterns . The MLS erythromycin-resistant phenotype is due to the enzymatic methylation of ribosomal RNA that blocks erythromycin binding to the ribosome . Alternatively, in isolates of the M phenotype, a more recently documented mechanism, resistance is associated with an active efflux process that reduces intracellular levels of erythromycin . We used two-dimensional electrophoresis to examine the proteins synthesised by erythromycin-susceptible and -resistant S . pneumoniae . Erythromycin-resistant S . pneumoniae with the M phenotype showed a significantly increased synthesis of a 38,500 Dalton (pI 6.27) protein compared to susceptible isolates . Peptide mass mapping was used to identify the 38,500 Dalton protein as glyceraldehyde-3-phosphate dehydrogenase (GAPDH) . It was demonstrated that S . pneumoniae synthesised at least three forms of GAPDH that differed in their isoelectric points . The form of GAPDH possessing the most basic pI showed the increased synthesis in the erythromycin-resistant S . pneumoniae isolates . Alterations in the synthesis of GAPDH were only found for those erythromycin-resistant isolates possessing the M phenotype . S . pneumoniae isolates with the MLS phenotype were indistinguishable from the susceptible strains using the analytical conditions employed for the current study . The possible role of GAPDH in erythromycin resistance of S . pneumoniae is considered.

Int J Antimicrob Agents, 1999 Aug, 12(4), 349 - 54
Drug-resistant Streptococcus pneumoniae in the Lebanon: implications for presumptive therapy; Araj GF et al.; A total of 50 consecutive clinical isolates of Streptococcus pneumoniae, collected between 1996 and 1998, were tested against six antimicrobial agents using the E-test . The percentages of fully resistant (R) and intermediately-R strains, respectively, were: benzyl penicillin 18 and 38%, amoxycillin-clavulanate 6 and 12%, cefuroxime 22 and 16%, ceftriaxone 2 and 16%, and clarithromycin 10% . Fully and or intermediately multidrug-resistance (two or more drugs) was seen in 44% of the isolates, 18% being fully resistant . The MIC breakpoint for cefaclor is not defined by the National Committee for Clinical Laboratory Standards (NCCLS) but MICs showed that: 76% of the isolates had an MIC of < or = 8 mg/l, 4% had an MIC of 16 mg/l and 20% had an MIC of > or = 32 mg/l . There was agreement between the E-test Pen MIC results and the 1 microg oxacillin (oxa) disk diffusion screen test for the 22 susceptible and the nine fully R strains but not for the 19 strains with Pen MICs between 0.1 and 1 mg/l; this shows the importance of MIC determination in such isolates . Penicillin and multiply antibiotic-resistant pneumococci are spreading in Lebanon, emphasizing the necessity to reconsider current treatment regimens in this country.

J Am Anim Hosp Assoc, 1999 Sep-Oct, 35(5), 417 - 22
Streptococcal meningoencephalitis in a dog; Irwin PJ et al.; A 5.5-year-old French bulldog was presented with acute neck pain and a short history of central vestibular syndrome . A marked neutrophilic pleocytosis and numerous gram-positive cocci were evident on cerebrospinal fluid (CSF) cytology . Streptococcus pneumoniae, a pathogen of humans, was isolated upon CSF microbiological culture . Treatment consisted of intravenous antibiotics, supportive care, and anticonvulsants for the generalized seizures which developed shortly after admission . The dog responded to therapy and two years later exhibited only a mild, residual head tilt . The pathogenesis and treatment of bacterial meningoencephalitis in dogs are reviewed.

Pediatr Infect Dis J, 1999 Sep, 18(9), 806 - 10
Neonatal group B streptococcal disease in Finland: a ten-year nationwide study; Kalliola S et al.; BACKGROUND: Group B Streptococcus (GBS) is the most common cause of invasive infections in newborns . GBS bacteria are typed on the basis of capsular polysaccharides or surface-localized proteins . Both polysaccharides and protein antigens have been suggested as potential vaccine candidates . METHODS: A prospective nationwide laboratory-based study of invasive GBS infections in children younger than 3 months of age was conducted in 1985 through 1994 . Isolates were serotyped by immunodiffusion in agar gel with HCl extracts and rabbit antisera . Clinical diagnoses and case fatalities were verified from the patient records or the national hospital discharge register . RESULTS: There were 485 cases registered during the 10-year period . The incidence of disease was 0.76/1000 live births . The case fatality rate was 8.0% . Of the 485 cases 398 (83%) were early onset and 87 (17%) late onset infections . The most common clinical diagnosis was bacteremia (77%) without an identified focus of infection . Other diagnoses included meningitis (17%), pneumonia (3%), osteomyelitis or septic arthritis (2%), pyelonephritis or cellulitis . Serotyping of 395 isolates revealed that 47% were of serotype III or III/R, 23% of Ia/c, 11% of Ib, 6% of II/R, 8% of IV, 1% of V and 7% were nontypable . CONCLUSIONS: The clinical picture of GBS disease and serotype distribution are similar to what has been reported from other countries . Serotypes III and III/R dominated (47% of all infections), especially in late onset disease . On the basis of these results a GBS vaccine including at least the Ia, Ib, II and III components would provide coverage against 88% of GBS serotypes causing neonatal disease in Finland.

Plasmid, 1999 Sep, 42(2), 154 - 7
Firefly luciferase as a reporter to study gene expression in Streptococcus mutans; Goodman SD et al.; The utility of firefly luciferase as a reporter was tested in Streptococcus mutans . Under control of an endogenous promoter, the luciferase coding sequence was strongly expressed, while a promoterless version was indistinguishable from the background . Luciferase activity was easily extracted and the assay rapid and reproducible . In addition, the half-life of luciferase activity was found to be comparable to those of other frequently used reporters . Thus, firefly luciferase can readily be used as a reporter in S . mutans, a useful alternative to methods requiring radioactive isotopes .

MMWR Morb Mortal Wkly Rep, 1999 Aug 6, 48(30), 656 - 61
Geographic variation in penicillin resistance in Streptococcus pneumoniae--selected sites, United States, 1997; Improved detection of Streptococcus pneumoniae in middle-ear fluid cultures by use of a gentamicin-containing medium; Clinical Microbiology Laboratory, Soroka Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, IsraelThe performance of Columbia agar medium with added sheep blood and gentamicin (CAG) for isolation of Streptococcus pneumoniae from middle-ear fluid cultures was compared to that of routine blood agar medium (BA) . Of 238 pneumococcal isolates recovered, CAG plates detected 233 (97.9%) but BA plates detected only 208 (87.4%) (P < 0 . 001).

J Clin Microbiol, 1999 Oct, 37(10), 3384 - 6
Is there an ecological relationship between rates of antibiotic resistance of species of the genus Streptococcus? The Spanish Surveillance Group for Respiratory Pathogens; Gomez-Lus R et al.; The relationship between resistance to antibiotics on the part of Streptococcus pneumoniae and Streptococcus pyogenes was studied by comparing different prevalences of resistance among hospitals obtained from a recent microbiological surveillance of community-acquired respiratory tract infections . A high correlation for erythromycin resistance was found between S . pneumoniae isolates from lower respiratory tract infections and S . pyogenes isolates collected from pharyngeal swabs.

J Clin Microbiol, 1999 Oct, 37(10), 3308 - 15
Prophage carriage as a molecular epidemiological marker in Streptococcus pneumoniae; Severina E et al.; The great majority of clinical isolates of Streptococcus pneumoniae carry prophages that may be identified through their hybridization with a DNA probe specific for the pneumococcal lytA gene (M . Ramirez, E . Severina, and A . Tomasz, J . Bacteriol . 181:3618-3625, 1999) . We now show that the lytA hybridization pattern of chromosomal SmaI digests is stable for a given strain during extensive serial culturing in the laboratory; the pattern is specific for the strain's clonal type, as defined by pulsed-field gel electrophoretis (PFGE) pattern, and variations in PFGE subtypes may be explained by changes in the number and chromosomal localization of this prophage(s) . These observations indicate that the lytA hybridization pattern may be used as a molecular epidemiological marker that offers additional resolution of the genetic background of S . pneumoniae strains.

J Clin Microbiol, 1999 Oct, 37(10), 3296 - 9
Comparison of agar dilution, microdilution, E-test, and disk diffusion methods for testing activity of cefditoren against Streptococcus pneumoniae; Kelly LM et al.; This study evaluated the susceptibility of pneumococci to cefditoren by agar dilution and microdilution methods (both in air) and by E-test (AB Biodisk, Solna, Sweden) and disk diffusion methods (both in CO(2)) . By the three MIC tests, the MICs at which 50 and 90% of isolates were inhibited (MIC(50)s and MIC(90)s) were, respectively, as follows (in micrograms per milliliter): for the 65 penicillin-susceptible strains tested, 0.016 and 0.03 (by agar dilution), 0.016 and 0.03 (by microdilution), and 0.016 and 0.03 (by E test); for the 68 penicillin-intermediate strains tested, 0.125 and 0.5 (by agar dilution), 0.125 and 0.5 (by microdilution), and 0 . 25 and 0.5 (by E test); and for the 67 penicillin-resistant strains tested, 1.0 and 1.0 (by agar dilution), 0.5 and 1.0 (by microdilution), and 1.0 and 1.0 (by E test) . With tentative cefditoren breakpoints (in micrograms per milliliter) of </=2.0 (susceptible), 4.0 (intermediate), and >/=8.0 (resistant), all strains were susceptible to cefditoren by agar, microdilution, and E-test results; with breakpoints of </=1.0, 2.0, and >/=4.0 microg/ml, 97% of strains were cefditoren susceptible by agar dilution results, 98% were susceptible by microdilution results, and 99% were susceptible by E-test results . When microdilution and E-test results were compared to those from the reference agar dilution method, 191 (95.5%) and 183 (91.5%) of strains gave essential agreement (+/-1 log(2) dilution); 8 (2.7%) minor discrepancies were found for both methods with a breakpoint of </=1 . 0 microg/ml, and no discrepancies were found with a breakpoint of </=2.0 microg/ml . Disk test results (breakpoint, </=1.0 microg/ml) produced 2 major and 30 minor errors, with corresponding zone diameters (in millimeters) of >/=20 (susceptible), 17 to 19 (intermediate), and </=16 (resistant); a </=2.0-microg/ml breakpoint yielded zone diameters of >/=16 mm (susceptible) . All three methods for testing the MIC of cefditoren showed excellent correlation.

J Clin Microbiol, 1999 Oct, 37(10), 3210 - 6
The three major Spanish clones of penicillin-resistant Streptococcus pneumoniae are the most common clones recovered in recent cases of meningitis in Spain; Enright MC et al.; One hundred six isolates of Streptococcus pneumoniae recovered in Spain from patients with meningitis in 1997 and 1998 were characterized by multilocus sequence typing . A heterogeneous collection of genotypes was associated with meningitis in Spain: 65 different sequence types were resolved and, even at a genetic distance of 0.43, there were 37 distinct lineages . Thirty-eight percent of the isolates, including all isolates of serotypes 6B, 9V, 14, and 23F, were resistant to penicillin, and 24% of the isolates were members of the three major Spanish penicillin-resistant or multidrug-resistant clones of serotypes 6B, 9V, and 23F or serotype variants of these clones . These three clones (MICs, 1 to 2 microg of penicillin/ml) were the most common clones associated with pneumococcal meningitis in Spain during 1997 and 1998 . Only two of the other clones associated with meningitis were penicillin resistant (MICs, 0.12 to 0.5 microg/ml) . One of the two most prevalent penicillin-susceptible clones causing meningitis (serotype 3) has not been detected outside of Spain, whereas the other (serotype 18C) has been recovered from patients with meningitis in the United Kingdom, The Netherlands, and Denmark . The prevalence of meningitis caused by isolates of the three major Spanish penicillin-resistant or multiply antibiotic-resistant clones, which are now globally distributed, is disturbing and clearly establishes their ability to cause life-threatening disease.

J Clin Microbiol, 1999 Oct, 37(10), 3146 - 52
The cps genes of Streptococcus suis serotypes 1, 2, and 9: development of rapid serotype-specific PCR assays; Smith HE et al.; We developed three type-specific PCR assays for the rapid and sensitive detection of Streptococcus suis serotype 1 (plus 14), serotype 2 (plus 1/2), and serotype 9 strains in tonsillar specimens from pigs . The PCR primers were based on the sequences of type-specific capsular genes of S . suis serotype 1, 2, and 9 strains . We recently characterized a major part of the capsular biosynthesis (cps) locus of S . suis serotype 2 . Here we extended these studies and characterized major parts of the cps loci of S . suis serotypes 1 and 9 . Type-specific genes were identified by cross-hybridization experiments between the individual cps genes and chromosomal DNAs from the 35 different serotypes . Four genes of S . suis serotype 1 specifically hybridized with serotype 1 and 14 strains only . Five genes of S . suis serotype 2 specifically hybridized with serotype 2 and 1/2 strains only, and two genes of S . suis serotype 9 specifically hybridized with serotype 9 strains . Until now rapid and sensitive diagnostic tests were available only for pathogenic strains of serotype 2 and highly pathogenic strains of serotype 1 . The serotype-specific PCR assays can therefore be useful tools for the identification of serotype 1, 14, 2, 1/2, and 9 strains both for diagnostic purposes and in epidemiological and transmission studies . Therefore, these tests may facilitate control and eradication programs.

Respir Physiol, 1999 Aug 3, 116(2-3), 201 - 9
Combined effects of both bacteria and gastric juice on pneumonia in mice; Iwasaki K et al.; The effects of a combined inoculation of gastric juice and Streptococcus pneumoniae on the lungs of mice was investigated . Survival rates of mice inoculated with bacteria alone, gastric juice alone, and both bacteria and gastric juice were compared over 18 days . Xanthine oxidase (XO) activities in the lung tissues of mice inoculated with bacteria and gastric juice were measured and injected with a free radical scavenger, pyran-superoxide dismutase (pyran-SOD) . A high mortality rate was observed in mice inoculated with both gastric juice and Streptococcus pneumoniae (81%) . Mice inoculated with either Streptococcus pneumoniae or gastric juice showed a separate mortality rate of up to 10% during 18 days after inoculation . XO activity in the lung tissue of the mice inoculated with both gastric juice and bacteria was higher than in mice inoculated with either of them separately . The high mortality rate in the group inoculated with both two agents was reduced to 25% by the administration of pyran-SOD . XO activity raised by Streptococcus pneumoniae and gastric juice was significantly reduced by pyran-SOD . Thus, we suggest an important role in the combined effects of gastric juice and bacteria on pneumonia.

Curr Microbiol, 1999 Oct, 39(4), 180 - 6
Proteolytic activities of the starch-fermenting ruminal bacterium, Streptococcus bovis; Griswold KE et al.; The objective of this study was to characterize the extracellular proteolytic activity of Streptococcus bovis . Strains KEG, JB1, NCFB 2476, and K11.21.09.6C produced very similar large molecular weight (160-200 kDa) extracellular proteases that were specifically inhibited by PMSF, a serine protease inhibitor . Further experiments with S . bovis KEG indicated that cultures grown with casein as the sole added N source produced the greatest level of proteolytic activity, and the level of proteolytic activity was independent of growth rate . Clarified ruminal fluid (CRF) decreased proteolytic activity by 54% compared with cultures grown with casein alone, and addition of exogenous peptides and carbohydrates (CHO) to the CRF further reduced the level of proteolytic activity by 44% and 52%, respectively . These results suggested that the proteolytic activity of S . bovis KEG was modulated by available N source and that the proteolytic activity was present for reasons other than providing N for growth . The role of S . bovis in ruminal proteolysis requires further definition, but phenotypic similarity among some ruminal strains would suggest a common niche in ruminal proteolysis . The uniformity of proteolytic activities could make S . bovis a prime candidate for manipulation in ruminal proteolysis control strategies.

MMWR Morb Mortal Wkly Rep, 1999 Aug 13, 48(31), 681 - 3
Use of pulsed-field gel electrophoresis for investigation of a cluster of invasive group A streptococcal illness--Spokane, Washington, 1999; Incubation of Streptococcus uberis with extracellular matrix proteins enhances adherence to and internalization into bovine mammary epithelial cells; Department of Animal Science, University of Tennessee, Knoxville 37996, USA . soliver@utk.edu

Two strains of Streptococcus uberis (UT 888 and UT 366) isolated from cows with clinical mastitis were co-cultured with bovine mammary epithelial cells (MAC-T) with and without laminin, fibrinogen, fibronectin or collagen . Incubation of S . uberis with extracellular matrix proteins (ECMPs) increased adherence to and internalization into MAC-T cells . Both strains of S . uberis exhibited greater adherence when co-cultured in the presence of collagen than with any other ECMP . However, adherence was always higher when strains were co-cultured with ECMP than in medium alone . S . uberis UT 888 adhered better to MAC-T cells than S . uberis UT 366 . The influence of ECMPs on bacterial internalization into MAC-T cells was similar to adherence, however, differences among ECMPs were less noticeable . S . uberis UT 888 had a higher internalization index than S . uberis UT 366 . It is possible that ECMPs induce or up-regulate proteins that selectively adhere to ECMPs which could serve as a bridge between the eukaryotic cell and the bacterial pathogen that leads to internalization of the ECMP-bound pathogen into the mammary epithelial cell.

Nervenarzt, 1999 Aug, 70(8), 738 - 41
{Streptococcus suis meningitis and neurophysiology of the acoustic system . First case report from Austria}; Spiss HK et al.; Meningitis caused by Streptococcus suis was diagnosed in a 63 year old female in Austria . Sixteen months after onset she still suffers from ataxia, disturbance of gait and bilateral hearing impairment . Being a farmer, the patient belongs to a recognized high-risk-group, as most other infected people do . To the best of our knowledge, there has been no report of a human infection by Streptococcus suis in Austria so far . The results of neurophysiological tests excluded a direct lesion to the cochlea during the acute phase of meningitis, and thus, are in contrast to the guinea-pig-model by Kay, who showed suppurative labyrinthitis being the cause of hearing loss . The present knowledge of Streptococcus suis meningitis with respect to neurophysiology, pathogenesis, epidemiology and increasing resistance against antibiotics is discussed.

J Med Microbiol, 1999 Sep, 48(9), 863 - 6
Detection of pneumolysin in sputum; Wheeler J et al.; Western blot detection of the species-specific pneumococcal product, pneumolysin (SPN), was shown to be almost as sensitive as PCR for the non-cultural detection of pneumococci in 27 Streptococcus pneumoniae culture-positive sputa from patients stated to have chest infections . Both techniques were considerably more sensitive than counter-current immuno-electrophoresis for pneumococcal capsular polysaccharide antigens (CPS-CIE) on the same specimens . Sensitivities for PCR, SPN-immunoblotting and CPS-CIE were 100%, 85% and 67%, respectively . In 11 S . pneumoniae culture-negative sputa taken from patients receiving antibiotics, but with proven recent pneumococcal infection, PCR and SPN-blot were positive in six (in two of which CPS-CIE was also positive), PCR alone was positive in one and SPN-blot alone was positive in one . In 11 S . pneumoniae culture-negative samples from patients not receiving antibiotics, all three tests were negative in eight, PCR was positive in three (in one of which CPS-CIE was also positive), but SPN-blot was negative in all 11 . In 16 S . pneumoniae culture-negative samples from patients receiving antibiotics and with no known recent pneumococcal infections, one or more non-cultural test was positive in 11 . Although further evaluation is required to assess the significance of pneumolysin detection in relation to carriage and infection and to devise a more suitable test format, these preliminary studies suggest that pneumolysin detection is a promising new approach to the non-cultural diagnosis of pneumococcal chest infection.

Scand J Infect Dis, 1999, 31(3), 316 - 7
Group B streptococcal vertebral osteomyelitis with bacteraemia in an adult with no debilitating condition; Mouly S et al.; A previously healthy 62-year-old immunocompetent woman presented with group B streptococcal vertebral osteomyelitis . Group B Streptococcus was recovered in 3 consecutive blood cultures . The patient recovered fully after treatment including antibiotic therapy, bed rest and physical rehabilitation . Group B streptococcal vertebral osteomyelitis is uncommon and has not previously been reported in patients with no immunosuppressive condition.

Eur J Clin Microbiol Infect Dis, 1999 Jul, 18(7), 522 - 4
Influence of increased macrolide consumption on macrolide resistance of common respiratory pathogens; Cizman M et al.; The impact of increased macrolide consumption on the resistance of common respiratory pathogens to erythromycin and azithromycin was evaluated . The study focused mainly on azithromycin . During the period from 1991 to 1996, a 3.5-fold increase in macrolide prescriptions for outpatients was observed in Slovenia . Compared to 1994, when no macrolide resistance was evident in Streptococcus pyogenes and noninvasive Streptococcus pneumoniae, a significant increase in macrolide resistance was observed in these two pathogens in 1997 . Moraxella catarrhalis remained uniformly susceptible to macrolides . Close monitoring of macrolide resistance of common respiratory pathogens is thus necessary.

Eur J Clin Microbiol Infect Dis, 1999 Jul, 18(7), 506 - 9
Review of 17 cases of pneumonia caused by Streptococcus pyogenes; Barnham M et al.; Streptococcus pyogenes is an uncommon cause of community-acquired pneumonia and there have been few recent specific accounts of the condition . To describe the current nature of this disease in the UK, data was gathered on patients with clinical pneumonia from whom Streptococcus pyogenes was cultured principally from blood or other relevant normally sterile sites . In the Harrogate and Northallerton districts of North Yorkshire, pneumonia accounted for nine (20%) cases and a quarter of all deaths in a complete sequence of 45 patients with Streptococcus pyogenes bacteraemia detected during the 16-year-period 1981-1996 . An analysis is presented of those cases together with eight recent cases from counties York, Durham and Isle of Wight during 1995-1997 . Of the total 17 cases, nine occurred in women and eight in men; the age range was 30-92 years . The organism was isolated from blood culture in 15 (88%) patients . Eight (47%) patients died, five within 1 day of hospitalisation . Fourteen (82%) cases occurred in the winter months October to March, including all the fatal cases and all eight in which a clinical 'viral' prodrome was observed . Predisposing medical or surgical conditions were present in 65% of the patients . Major complications included septicaemia, pleural reaction, shock, pulmonary cavitation, osteomyelitis and metastatic abscesses . Seven serotypes of Streptococcus pyogenes were encountered, with M-type 1 predominating (the cause in 60% of cases) . All infections were community acquired; two small clusters of fatal pneumonia were seen.

Arch Dermatol Res, 1999 Jul-Aug, 291(7-8), 382 - 9
Hyporesponsiveness of peripheral blood lymphocytes to streptococcal superantigens in patients with guttate psoriasis: evidence for systemic stimulation of T cells with superantigens released from focally infecting Streptococcus pyogenes; Tokura Y et al.; Throat infection with Streptococcus pyogenes is the most important trigger for acute guttate psoriasis . We examined the in vitro responses of peripheral blood mononuclear cells (PBMC) to streptococcal superantigens, SPEA and SPEC, and staphylococcal superantigens, SEB and TSST-1, in patients with guttate psoriasis, in patients with chronic plaque psoriasis, and in healthy subjects . PBMC from patients with guttate psoriasis responded poorly to SPEA and SPEC at concentrations of 0.1 and 1 ng/ml as compared with those from patients with plaque psoriasis, but showed high responses to SEB and TSST-1 . The hyporesponsiveness recovered after improvement of the skin eruption . There was no significant difference between guttate and chronic types of psoriasis in the percentage of circulating T-cell receptor BV2 or BV8-bearing T cells, responsive to streptococcal superantigens, indicating that T-cell clonal anergy was a mechanism underlying the hyporesponsiveness . Our results suggest that superantigens released from focally infecting S . pyogenes induce a transient activation of relevant T cells, leading to the development of skin eruption and, subsequently, temporary T-cell anergy to these toxins.

Kansenshogaku Zasshi, 1999 Jul, 73(7), 664 - 74
{Influence of dexamethasone on the clinical course of bacterial meningitis in children . Especially on secondary fever . Experiences in 27 institutions}; Kobayashi Y et al.; Of pediatric patients with purulent meningitis seen at the institutions listed in the title page of this paper between 1986 and 1994, 93 patients treated with antibiotics and dexamethasone (DXM) were compared with 91 patients treated with antibiotics alone . The patients receiving antibiotics with dexamethasone achieved overall improvement in inflammatory symptoms and signs and cerebrospinal fluid findings and became afebrile significantly earlier than those receiving antibiotics alone . However, some of the patients became febrile again . The secondary fever rate for the DXM group was much higher than that for the antibiotic alone group (p < 0.0001) . In most of the rebounded cases, the body temperature rose above 38 degrees C and remained elevated for 2-4 days . Cerebrospinal fluid (CSF) was cultured daily in 54 and 32 patients receiving antibiotics with and without DXM, respectively . Although this study was not a controlled study in a strict sense, these patients compared . In both groups, the CSF became mostly culture-negative within 48 hours . In a few patients receiving DXM, however, it became culture-negative after 72 hours or longer . DXM caused an adverse effect in a patient with meningitis caused by Streptococcus pneumoniae . The adverse effect was mild gastrointestinal bleeding, which recovered spontaneously . From the findings described above, the use of DXM combined with antibiotic therapy was considered to accelerate the relief from fever and improvement of inflammatory symptoms and signs and CSF findings . The body temperature rose again in more than half of the patients receiving DXM, but fell to normal spontaneously without treatment . The elevation doubtlessly could not be distinguished from recurrence of the meningitis itself or complications . It seems to be likely that no treatment but careful observation is required even if the fever recurs as far as the CSF findings showed favorable progress with excelluent general conditions . When DXM is given, it is essential that CSF tests and culture are repeated during the early stages and the progress is monitored carefully.

J Dairy Sci, 1999 Aug, 82(8), 1671 - 83
Effect of recombinant bovine somatotropin on milk production and composition of cows with Streptococcus uberis mastitis; Hoeben D et al.; The protective effect of bovine somatotropin (bST) during experimental Streptococcus uberis mastitis in cows was studied . The left quarters of 10 cows were infected with 500 cfu of S . uberis O140J . Five cows were subcutaneously treated with 500 mg of recombinant bST 7 d before and after infection, and 5 control cows received the excipient . In the treated cows, total milk production significantly increased after the first and second bST treatments . After infection, milk production decreased 24 and 40% in the infected quarters, 6 and 14% in the uninfected quarters, and 15 and 28% overall for treated and control cows, respectively . In the bST group, milk production was completely restored after 3 wk, but, in the control group, total production and the production of the infected quarters remained lower than preinfection production . The increase in somatic cell count occurred earlier and more rapidly in the control group, and the return to normal values was also more rapid in these cows . The amount of bacteria in milk was higher in the control cows . Changes in milk composition, such as lactose, protein, fat, Na+, K+, and Cl-, were significantly more pronounced in the control cows . Also, clinical symptoms were more prominent in the control cows . Somatotropin protected the mammary gland from excessive production losses and compositional changes during a subsequent episode of experimentally induced Streptococcus uberis mastitis and significantly improved the normalization of production and composition, which indicates a beneficial effect on the restoration of the integrity of the blood-milk barrier.

J Dairy Sci, 1999 Aug, 82(8), 1643 - 54
Management practices associated with the incidence rate of clinical mastitis; Barkema HW et al.; Risk factors for the incidence rate of clinical mastitis were studied in 274 Dutch dairy herds . Variables that were associated with resistance to disease were the feeding, housing, and milking machine factors . Variables that were associated with exposure were grazing, combined housing of dry cows and heifers, and calving area hygiene . Postmilking teat disinfection in herds with a low bulk milk somatic cell count and years of practicing dry cow therapy were positively associated with the incidence rate of clinical mastitis . Herds with a low bulk milk somatic cell count and in which postmilking teat disinfection was not used had lower incidence rates of clinical mastitis than did other herds . The incidence rate of clinical mastitis caused by Escherichia coli was mostly related to housing conditions, hygiene, and machine milking . The incidence rate of clinical mastitis caused by Staphylococcus aureus was mostly related to factors associated with bulk milk somatic cell count and factors that might be due to cause and effect reversal . A strong positive correlation existed between the incidence rate of clinical mastitis caused by Streptococcus dysgalactiae and the incidence rate of clinical mastitis caused by Staph . aureus . The incidence rate of clinical mastitis caused by Streptococcus dysgalactiae was related to nutrition, milking technique, and machine milking . The incidence rate of clinical mastitis caused by Streptococcus uberis was associated with factors related to housing, nutrition, and machine milking.

Panminerva Med, 1999 Jun, 41(2), 171 - 4
Pneumococcal arthritis in the wrist and ankle . A case report and short review of the literature; Levi N et al.; In this paper we report a 48-year-old man with septic arthritis of the wrist and ankle due to Streptococcus pneumoniae . No known predisposing factor was found . Only about 300 cases of pneumococcal arthritis have been reported in the literature since 1888 and less than 10% of these affect the wrist . The management of bacterial arthritis is reviewed.

Ophthalmologe, 1999 Jul, 96(7), 459 - 64
{Bacterial keratitis . Microbiological analysis as a principle for therapeutic recommendations}; Frohlich SJ et al.; PURPOSE: The study presented differentiates between the aetiological agents of bacterial keratitis in patients with and without a history of contact lens wear . Based on these results, recommendations are given for optimal antibiotic primary therapy . PATIENTS AND METHODS: Swabs and corneal scrapings were taken from 218 patients referred to the University Eye Hospital in Munich with a diagnosis of bacterial keratitis from 1989 to 1997 . Ninety-two of these patients had a history of contact lens wear; 126 had none . The germs were isolated and identified by staining and microscopy . Observing polymicrobial growth in 51 patients, a total of 275 germs was isolated . RESULTS: The most frequent pathogens were Staphylococcus epidermidis (44%), S . aureus (18%), Streptococcus spp . (10%), Propionibacterium acnes (7%) and Pseudomonas aeruginosa (6%) . Gram-negative germs were nearly exclusively isolated from contact lens wearers, gram-positive germs were predominant in non-contact lens wearers . CONCLUSION: Keratitis in patients with a history of contact lens wear is often caused by aggressive gram-negative germs . Those cases should immediately be treated with quinolones and erythromycin . In keratitis caused by gram-positive pathogens, a combination with aminoglycosides and erythromycin is sufficient.

J Immunol, 1999 Sep 15, 163(6), 3396 - 402
Fc-mediated nonspecific binding between fibronectin-binding protein I of Streptococcus pyogenes and human immunoglobulins; Medina E et al.; Fibronectin-binding protein I (SfbI) from Streptococcus pyogenes plays a key role in bacterial adhesion to, and invasion of, eukaryotic cells . In addition, SfbI exhibits a considerable potential as mucosal adjuvant and can trigger polyclonal activation of B cells . Here, we report that SfbI is also capable of binding human IgG in a nonimmune fashion . SfbI was reactive with IgG1, IgG2, IgG3, and IgG4 isotypes (type IIo IgG-binding profile) . The affinity constant (Kd) of the SfbI-IgG interaction was in the range of 1-2 x 10(-5) M . Further studies demonstrated that the SfbI binding was mediated by the Fc component of the IgG molecule . Experiments performed using purified recombinant proteins spanning different domains of SfbI showed that the IgG-binding activity was restricted to the fibronectin-binding domains, and in particular to the fibronectin-binding repeats . Finally, the presence of recombinant SfbI resulted in an impairment of both phagocytosis of IgG-coated RBCs and Ab-dependent cell cytotoxicity by macrophages . These results demonstrated for the first time that, in addition to its major role during the colonization process, SfbI may also favor bacterial immune evasion after the onset of the infection by interfering with host clearance mechanisms.

J Immunol, 1999 Sep 15, 163(6), 3029 - 36
Human dendritic cells very efficiently present a heterologous antigen expressed on the surface of recombinant gram-positive bacteria to CD4+ T lymphocytes; Corinti S et al.; Recombinant Streptococcus gordonii expressing on the surface the C-fragment of tetanus toxin was tested as an Ag delivery system for human monocyte-derived dendritic cells (DCs) . DCs incubated with recombinant S . gordonii were much more efficient than DCs pulsed with soluble C-fragment of tetanus toxin at stimulating specific CD4+ T cells as determined by cell proliferation and IFN-gamma release . Compared with DCs treated with soluble Ag, DCs fed with recombinant bacteria required 102- to 103-fold less Ag and were at least 102 times more effective on a per-cell basis for activating specific T cells . S . gordonii was internalized in DCs by conventional phagocytosis, and cytochalasin D inhibited presentation of bacteria-associated Ag, but not of soluble Ag, suggesting that phagocytosis was required for proper delivery of recombinant Ag . Bacteria were also very potent inducers of DC maturation, although they enhanced the capacity of DCs to activate specific CD4+ T cells at concentrations that did not stimulate DC maturation . In particular, S . gordonii dose-dependently up-regulated expression of membrane molecules (MHC I and II, CD80, CD86, CD54, CD40, CD83) and reduced both phagocytic and endocytic activities . Furthermore, bacteria promoted in a dose-dependent manner DC release of cytokines (IL-6, TNF-alpha, IL-1beta, IL-12, TGF-beta, and IL-10) and of the chemokines IL-8, RANTES, IFN-gamma-inducible protein-10, and monokine induced by IFN-gamma . Thus, recombinant Gram-positive bacteria appear a powerful tool for vaccine design due to their extremely high capacity to deliver Ags into DCs, as well as induce DC maturation and secretion of T cell chemoattractans.

Clin Infect Dis, 1999 Aug, 29(2), 281 - 8
Reduction in functional antibody activity against Streptococcus pneumoniae in vaccinated elderly individuals highly correlates with decreased IgG antibody avidity; Romero-Steiner S et al.; The pneumococcal polysaccharide vaccine is recommended as a means of preventing invasive disease in the elderly . We compared responses to the 23-valent polysaccharide vaccine in 46 previously unvaccinated, healthy, institutionalized elderly persons (mean age, 85.5 years) with those in 12 healthy younger adults (mean age, 37 years) by measuring prevaccination and postvaccination serum IgG antibody concentrations (by ELISA), functional antibody activity (by opsonophagocytosis), IgG antibody avidity, and passive protection in mice . Postvaccination IgG antibody concentrations for two serotypes (6B and 19F) of the five studied (4, 6B, 14, 19F, and 23F) were significantly lower in elderly than in younger adults; however, opsonophagocytic activity was significantly reduced for all serotypes in the elderly . Sera with reduced opsonophagocytic activity (titer, <64) correlated with low IgG antibody avidity and protected mice poorly against pneumococcal challenge . In elderly persons receiving polysaccharide vaccination, there was a significant reduction in the functionality of postvaccination antibodies, and this appeared to increase with advanced age.

J Cataract Refract Surg, 1999 Sep, 25(9), 1295 - 8
Endophthalmitis after phakic intraocular lens implantation to correct high myopia; Perez-Santonja JJ et al.; A 36-year-old woman had uneventful implantation of an angle-supported anterior chamber phakic intraocular lens (IOL) to correct high myopia . On the first postoperative day, she developed infectious endophthalmitis likely associated with intraoperative contamination . Group B beta-hemolytic Streptococcus endophthalmitis was confirmed by microbiologic studies . To our knowledge, this is the first documented case of infectious endophthalmitis after anterior chamber phakic IOL implantation to correct high myopia.

Mol Microbiol, 1999 Sep, 33(5), 971 - 81
Insertion of a Yop translocation pore into the macrophage plasma membrane by Yersinia enterocolitica: requirement for translocators YopB and YopD, but not LcrG; Neyt C et al.; The Yersinia survival strategy is based on its ability to inject effector Yops into the cytosol of host cells . Translocation of these effectors across the eukaryotic cell membrane requires YopB, YopD and LcrG, but the mechanism is unclear . An effector polymutant of Y . pseudotuberculosis has a YopB-dependent contact haemolytic activity, indicating that YopB participates in the formation of a pore in the cell membrane . Here, we have investigated the formation of such a pore in the plasma membrane of macrophages . Infection of PU5-1.8 macrophages with an effector polymutant Y . enterocolitica led to complete flattening of the cells, similar to treatment with the pore-forming streptolysin O from Streptococcus pyogenes . Upon infection, cells released the low-molecular-weight marker BCECF (623 Da) but not the high-molecular-weight lactate dehydrogenase, indicating that there was no membrane lysis but, rather, insertion of a pore of small size into the macrophage plasma membrane . Permeation to lucifer yellow CH (443 Da) but not to Texas red-X phalloidin (1490 Da) supported this hypothesis . All these events were found to be dependent not only on translocator YopB as expected but also on YopD, which was required equally . In contrast, LcrG was not necessary . Consistently, lysis of sheep erythrocytes was also dependent on YopB and YopD, but not on LcrG.

J Endocrinol Invest, 1999 Jul-Aug, 22(7), 535 - 40
Homologies of the thyroid sodium-iodide symporter with bacterial and viral proteins; Benvenga S et al.; We have demonstrated that Na+/I- symporter (NIS), a novel thyroid autoantigen, has local amino acid sequence homologies with the other thyroid autoantigens: Thyroglobulin (Tg), thyroid peroxidase (TPO) and thyrotropin receptor (TSH-R) . These homologies concern the 4th, 5th, 6th extracellular loop and the beginning of the intracellular tail . We have expanded our studies and found that there are significant local homologies with other 11 proteins, most of them of bacterial or viral origin (e.g., Streptococcus or Herpes) . These homologies concern the 2nd and 4th extracellular loop, and both the beginning and the end of the intracellular tail . These 11 homologies were retrieved by a computer-assisted search and extracted out of a database containing almost 300,000 amino acid sequences . These homologies were of magnitude greater than those concerning the three thyroid autoantigens {identities=51.1+/-7.3% vs 25.3+/-7.8% (mean+/-SD), p<0.001; similarities=70.6+/-10.7% vs 43.3+/-8.5%; p<0.001} . In addition, extensive, not local, homology was found with a number of unknown proteins from invertebrates (Drosophila melanogaster and Caenorhabditis elegans) and bacteria such as Bacillus subtilis and Xanthobacter . Previously, we had found that NIS has no extensive homology with Tg or TPO or TSH-R . This is the first demonstration of both extensive and local homologies between one thyroid autoantigen (NIS) and microbiological proteins . Taken together with data of the literature on the homologies between other thyroid antigens (Tg, TPO, TSH-R) and bacteria, the homologies we have now found reinforce the view that both bacterial and viral infections may trigger autoimmune thyroid diseases.

FEMS Microbiol Lett, 1999 Aug 15, 177(2), 313 - 7
Adherence and internalization of Streptococcus uberis to bovine mammary epithelial cells are mediated by host cell proteoglycans; Almeida RA et al.; The role of cell glycosaminoglycans (GAG) on adherence and internalization of Streptococcus uberis to bovine mammary epithelial cells was evaluated by adherence/internalization competition assays, by removal of GAG from the host cell surface and by inhibition of GAG glycosylation in the host cell . Heparin (HEP), heparan sulfate (HSA), chondroitin sulfate A (CSA) and chondroitin sulfate B (CSB) inhibited adherence and internalization of S . uberis in a dose-dependent manner . However, inhibition was lower with CSA and CSB than that observed with HEP and HSA . Adherence and internalization were also inhibited upon treatment of mammary epithelial cells with GAG lyases . The greatest inhibition was observed with heparinase I . Tunicamycin, an inhibitor of mammalian cell glycosylation of cell surface glycoproteins, markedly inhibited internalization of S . uberis into mammary epithelial cells . Differences between strains were observed . These results suggest that a HSA proteoglycan receptor on the host cell surface may mediate S . uberis adherence to and internalization of bovine mammary epithelial cells.

Antimicrob Agents Chemother, 1999 Sep, 43(9), 2225 - 30
Novel expansions of the gene encoding dihydropteroate synthase in trimethoprim-sulfamethoxazole-resistant Streptococcus pneumoniae; Padayachee T et al.; A study of eight sulfonamide-resistant clinical isolates of Streptococcus pneumoniae revealed chromosomal mutations within the gene encoding dihydropteroate synthase that play a role in conferring resistance to sulfamethoxazole . The presence of the suld mutation, found previously only in a laboratory mutant, was shown to occur in three of the wild-type clinical isolates . The duplication of Ser(61), the other previously defined mutation in the dihydropteroate synthase gene of S . pneumoniae, was observed in only one of the isolates characterized . We report two previously unidentified amino acid alterations, namely, a duplication of Arg(58) and Pro(59) and an insertion of an arginine residue between Gly(60) and Ser(61) in trimethoprim-sulfamethoxazole-resistant strains . The significance of these mutations was confirmed by site-directed mutagenesis and by the transformation of a susceptible strain of S . pneumoniae to sulfamethoxazole resistance . Two resistant isolates did not contain any mutations within the gene encoding dihydropteroate synthase . The results presented suggest the independent generation of resistant mutations among South African clinical isolates . It is also proposed that the mechanism of sulfonamide resistance in S . pneumoniae involves the expansion of a specific region within dihydropteroate synthase, which probably forms part of the sulfonamide binding site.

Appl Environ Microbiol, 1999 Sep, 65(9), 3880 - 7
Purification of mutacin III from group III Streptococcus mutans UA787 and genetic analyses of mutacin III biosynthesis genes; Qi F et al.; Previously, members of our group reported the isolation and characterization of mutacin II from Streptococcus mutans T8 and the genetic analyses of the mutacin II biosynthesis genes (J . Novak, P . W . Caufield, and E . J . Miller, J . Bacteriol . 176:4316-4320, 1994; F . Qi, P . Chen, and P . W . Caufield, Appl . Environ . Microbiol . 65:652-658, 1999; P . Chen, F . Qi, J . Novak, and P . W . Caufield, Appl . Environ . Microbiol . 65:1356-1360, 1999) . In this study, we cloned and sequenced the mutacin III biosynthesis gene locus from a group III strain of S . mutans, UA787 . DNA sequence analysis revealed eight open reading frames, which we designated mutR, -A, -A', -B, -C, -D, -P, and -T . MutR bears strong homology with MutR of mutacin II, while MutA, -B, -C, -D, -P, and -T are counterparts of proteins in the lantibiotic epidermin group . MutA' has 60% amino acid identity with MutA and therefore appears to be a duplicate of MutA . Insertional inactivation demonstrated that mutA is an essential gene for mutacin III production, while mutA' is not required . Mutacin III was purified to homogeneity by using reverse-phase high-pressure liquid chromatography . N-terminal peptide sequencing of the purified mutacin III determined mutA to be the structural gene for prepromutacin III . The molecular mass of the purified peptide was measured by laser disorption mass spectrophotometry and found to be 2,266.43 Da, consistent with our supposition that mutacin III has posttranslational modifications similar to those of the lantibiotic epidermin.

J Antimicrob Chemother, 1999 Aug, 44(2), 201 - 7
Structures of existing and new quinolones and relationship to bactericidal activity against Streptococcus pneumoniae; Mitsuyama J; The in-vitro bactericidal profiles of a number of quinolones against Streptococcus pneumoniae were investigated . Tosufloxacin was found to be the most bactericidal quinolone at the optimum bactericidal:MIC ratio (OBMR), followed by levofloxacin, ciprofloxacin and sparfloxacin, in order of potency . After exposure at the OBMR of each quinolone for 2 h, tosufloxacin showed a post-antibiotic effect (PAE) about 2.3-2.6 times longer than the other quinolones . Compounds with a 2,4-difluorophenyl group at the N-1 position in the quinolone nucleus had the greatest bactericidal activity and PAE . This activity exceeded that found with substitution of the quinolone nucleus at the C-7 position . Although the bactericidal activities of the quinolones correlated well with their PAEs, they were not always consistent with their MICs . These results suggest that bactericidal activity and PAE are governed by factors other than those which determine the MIC values, and a 2,4-difluorophenyl group at the N-1 position in the quinolone nucleus may play an important role in the expression of bactericidal activity and PAE against S . pneumoniae.

Otolaryngol Head Neck Surg, 1999 Sep, 121(3), 190 - 4
Impact of resistant pneumococcus on rates of acute mastoiditis; Antonelli PJ et al.; OBJECTIVE: To determine whether the rate of acute mastoiditis is rising, specifically as a result of antibiotic-resistant strains of Streptococcus pneumoniae . METHODS: A retrospective chart review of all patients with a discharge diagnosis of acute mastoiditis between July 1, 1987, and June 30, 1997, was performed at our academic, tertiary-care medical center . There were no interventions, and the main outcome measures included the number of cases of acute or coalescent mastoiditis, stratified by pathogen, per year . RESULTS: The rate of acute mastoiditis as a proportion of yearly otorhinolaryngology admissions increased linearly over time (P = 0 . 024) . Pneumococcal-related rates of acute mastoiditis, expressed as a proportion of yearly hospital and otorhinolaryngology admissions, increased linearly over time (P = 0.002, P = 0.002) . All but 1 case of pneumococcal mastoiditis during the past 3 years were caused by penicillin-resistant strains . CONCLUSIONS: The emergence of antibiotic-resistant S pneumoniae may be responsible for an increasing rate of acute mastoiditis.

Am J Respir Crit Care Med, 1999 Sep, 160(3), 923 - 9
Severe community-acquired pneumonia . Risk factors and follow-up epidemiology; Ruiz M et al.; The aim of the study was to determine risk factors for severe community-acquired pneumonia (CAP) as well as to compare microbial patterns of severe CAP to a previous study from our respiratory intensive care unit (ICU) originating from 1984 to 1987 . Patients admitted to the ICU according to clinical judgment were defined as having severe CAP . For the study of risk factors, a hospital-based case-control design was used, matching each patient with severe CAP to a patient hospitalized with CAP but not requiring ICU admission . Microbial investigation included noninvasive and invasive techniques . Overall, 89 patients with severe CAP were successfully matched to a control patient . The presence of an alcohol ingestion of >/= 80 g/d (odds ratio {OR} 3.9, 95% confidence interval {CI} 1.4 to 10.6, p = 0.008) was found to be an independent risk factor for severe CAP and prior ambulatory antimicrobial treatment (OR 0.37, 95% CI 0.17 to 0.79, p = 0.009) to be protective . Streptococcus pneumoniae (24%) continued to be the most frequent pathogen; however, 48% of strains were drug-resistant . "Atypical" bacterial pathogens were significantly more common (17% versus 6%, p = 0.006) and Legionella spp . less common (2% versus 14%, p = 0.004) than in our previous study, whereas gram-negative enteric bacilli (GNEB) and Pseudomonas aeruginosa continued to represent important pathogens (6% and 5%, respectively) . Our findings provide additional evidence for the importance of the initiation of early empiric antimicrobial treatment for a favorable outcome of CAP . Variations of microbial patterns are only in part due to different epidemiological settings . Therefore, initial empiric antimicrobial treatment will also have to take into account local trends of changing microbial patterns.

Antimicrob Agents Chemother, 1999 Sep, 43(9), 2314 - 6
Bactericidal/permeability-increasing protein inhibits growth of a strain of Acholeplasma laidlawii and L forms of the gram-positive bacteria Staphylococcus aureus and Streptococcus pyogenes; Horwitz AH et al.; Bactericidal/permeability-increasing protein (BPI) inhibited growth of cell wall-deficient Acholeplasma laidlawii and L forms of certain strains of Staphylococcus aureus and Streptococcus pyogenes . However, the same strains of S . aureus and S . pyogenes with intact cell walls were not susceptible to the growth-inhibitory effects of BPI.

Antimicrob Agents Chemother, 1999 Sep, 43(9), 2283 - 90
Immunomodulation of pneumococcal pulmonary infection with N(G)-monomethyl-L-arginine; Bergeron Y et al.; It has recently become apparent that inflammatory reactions including nitric oxide (NO) release contribute to the outcome of pulmonary infections . To investigate the effect of N(G)-monomethyl-L-arginine (L-NMMA), a NO synthase inhibitor, on the pathogenesis of pneumococcal pneumonia, we inoculated CD(1) Swiss mice with 10(7) CFU of Streptococcus pneumoniae . Treatment with two daily subcutaneous injections of 3 mg of L-NMMA per kg of body weight (over a 5-day period) reproducibly delayed mortality, as the number of surviving mice 72, 84, and 96 h after infection was increased by 16.8% (P < 0.05), 25.0% (P < 0.005), and 11.5% (P < 0 . 05), respectively . In fact, the following chronology of events was noted in L-NMMA-treated infected animals, compared to the untreated infected controls . (i) At 12 to 24 h after infection, larger amounts of leukotriene B(4) in bronchoalveolar lavage (BAL) fluid associated with greater neutrophilia in lung tissue and alveolar spaces and more persistent release of tumor necrosis factor alpha, interleukin-1 alpha (IL-1alpha), and IL-6 were observed . (ii) At 24 to 72 h, there was better preservation of lung ultrastructure, including reduction of edema in the interstitium and protection of alveolar spaces, despite identical bacterial growth in lungs, in L-NMMA-treated infected animals than in untreated animals . (iii) At 72 to 96 h, the death rate was delayed, despite the absence of antibiotic therapy . In our experiment, partial blockade of NO release was achieved . These data indicate that NO plays an important role in the induction of tissue injury and death during pneumococcal pneumonia and that L-NMMA is helpful for host protection.

Vaccine, 1999 Jul 30, 17 Suppl 1, S105 - 8
Pneumococcal immunization and public health: the Canadian experience; Spika JS et al.; Pneumococcal vaccine has been poorly used in Canada, despite strong recommendations for its use by the Canadian National Advisory Committee on Immunization . In a recent survey of health officials, however, seven of the 12 Canadian provinces and territories were found to either have a programme for all persons > 65 years of age or were planning to implement one within the next year . Factors that have contributed to this increased interest include: better data on disease incidence and preventable illness from population-based surveillance; data on emerging resistance of Streptococcus pneumoniae in Canada to penicillin and other antimicrobials; implementation of vaccine programmes for the elderly by public health officials in Ontario, Nova Scotia and British Columbia; completion of a cost-benefit study of pneumococcal vaccine for Canada; and increased attention to pneumococcal vaccination at national immunization meetings and in the medical literature . Increased availability of vaccine and competitive pricing are also making programmes for the elderly more feasible and affordable . A national meeting entitled 'Preventing Pneumococcal Disease: A Canadian Consensus Conference' was held in February 1998 to further build on this growing interest.

Anticancer Res, 1999 May-Jun, 19(3A), 1865 - 71
Antiproliferative and apoptosis-inducing effects of an antitumor glycoprotein from Streptococcus pyogenes; Yoshida J et al.; An acidic glycoprotein (SAGP) purified from an extract of Streptococcus pyogenes has been shown to inhibit the growth of methylcholanthrene-induced fibrosarcoma A (Meth A) cells via pertussis toxin-sensitive GTP-binding protein . The present study revealed that SAGP has activity to induce apoptosis in Meth A cells as assessed by DNA fragmentation and cell morphology with chromatin staining . The SAGP-induced DNA fragmentation in Meth A cells was augmented by herbimycin A, an inhibitor of protein tyrosine kinase, and prevented by orthovanadate, an inhibitor of protein tyrosine phosphatase . The growth inhibitory effect of SAGP on Meth A cells was reduced by orthovanadate, whereas the effect tended to be increased by herbimycin A . Western blotting analysis using antiphosphotyrosine antibody demonstrated that tyrosine phosphorylation of 170 kDa cellular protein was diminished in the cells incubated with SAGP . The inhibition of protein tyrosine phosphorylation was neither observed in the cells incubated with SAGP and orthovanadate nor in the cells incubated with heat-inactivated SAGP . These findings indicate that inhibition of tyrosine phosphorylation by protein tyrosine phosphatase(s) may be responsible for the SAGP-induced apoptosis and inhibition of cell growth.

Eur J Oral Sci, 1999 Aug, 107(4), 290 - 6
Antibacterial activity of resin composites with silver-containing materials; Yoshida K et al.; Resin composites with antibacterial activity may be useful to decrease the frequency of secondary caries around restorations . The purposes of this study were to investigate the antibacterial activity of light-activated resin composites incorporating one of three silver-containing materials and to evaluate their long-term inhibitory effect against Streptococcus mutans The three types of silver-containing materials, Novaron (N), Amenitop (AM), and AIS, were incorporated into TEGDMA-UDMA-based light-activated resin composites, and the antibacterial activities, mechanical properties and release of silver ions were examined . Minimum inhibitory concentrations in suspensions of N, AM, and AIS against S . mutans were 1.1, 1.2, and 23.0 mg/ml, respectively . Resin composites incorporating 5 wt% of Novaron (N-5) and 7 wt% of Amenitop (AM-7) inhibited the growth of S . mutans after immersion in water for 3 months, whereas the resin composite incorporating 10 wt% of AIS did not . No significant difference in either compressive or flexural strength was observed between the control and N-5 composites after 1 d and 3 months storage in water . However, for AM-5 composite, there was a significant difference in both strength parameters between the two immersion periods . There was no or extremely little release of silver ions from the N-5 and AM-5 composites after 1 d or 3 months immersion in water . These results indicated that a light-activated resin composite incorporating silver-containing materials such as Novaron may be clinically useful due to its long-term inhibitory effect against S . mutans and favorable mechanical properties.

Vet Microbiol, 1999 Jul 1, 67(4), 277 - 86
In vivo pathogenicity and resistance to phagocytosis of Streptococcus equi strains with different levels of capsule expression; Anzai T et al.; The glossy non-encapsulated strain of Steptococcus equi, NCTC 9682, was compared with the matt strain Hidaka/95/2 which expresses a medium sized capsule and with the mucoid CF32 which expresses a large sized capsule in phagocytosis assays and for virulence in inoculated horses . The three strains, NCTC 9682, Hidaka /95/2 and CF32 produced 2.0, 3.1, and 5.3 mg/g wet cells respectively after 3 h incubation, but similar amounts of M-like proteins, cytotoxin and mitogen . NCTC 9682 showed no resistance to phagocytosis by equine neutrophils regardless of the presence of opsonin while strains Hidaka /95/2 and CF32 showed almost complete resistance to phagocytosis . Furthermore, NCTC 9682 produced no clinical disease although it infected the guttural pouch and caused seroconversion . Typical strangles with guttural pouch invasion was observed in all horses infected with encapsulated strains.

J Bacteriol, 1999 Sep, 181(17), 5389 - 94
Regulation of cell component production by growth rate in the group B Streptococcus; Ross RA et al.; Group B Streptococcus (GBS) is the leading cause of bacterial sepsis and meningitis among neonates . While the capsular polysaccharide (CPS) is an important virulence factor of GBS, other cell surface components, such as C proteins, may also play a role in GBS disease . CPS production by GBS type III strain M781 was greater when cells were held at a fast (1.4-h mass-doubling time {td}) than at a slow (11-h td) rate of growth . To further investigate growth rate regulation of CPS production and to investigate production of other cell components, different serotypes and strains of GBS were grown in continuous culture in a semidefined and a complex medium . Samples were obtained after at least five generations at the selected growth rate . Cells and cell-free supernatants were processed immediately, and results from all assays were normalized for cell dry weight . All serotypes (Ia, Ib, and III) and strains (one or two strains per serotype) tested produced at least 3.6-fold more CPS at a td of 1 . 4 h than at a td of 11 h . Production of beta C protein by GBS type Ia strain A909 and type Ib strain H36B was also shown to increase at least 5.5-fold with increased growth rate (production at a td of 1 . 4 h versus 11 h) . The production of alpha C protein by the same strains did not significantly change with increased growth rate . The effect of growth rate on other cell components was also investigated . Production of group B antigen did not change with growth rate, while alkaline phosphatase decreased with increased growth rate . Both CAMP factor and beta-hemolysin production increased fourfold with increased growth rate . Growth rate regulation is specific for select cell components in GBS, including beta C protein, alkaline phosphatase, beta-hemolysin, and CPS production.

J Bacteriol, 1999 Sep, 181(17), 5373 - 83
Regulation of mga transcription in the group A streptococcus: specific binding of mga within its own promoter and evidence for a negative regulator; McIver KS et al.; Transcription of mga, encoding the multiple virulence gene regulator of the group A streptococcus, is positively autoregulated . This regulation requires a DNA region (Pmga) that contains both a promoter proximal to mga (P2) and a promoter located further upstream (P1) . To determine if Mga has a direct role in this process, its ability to bind to specific sequences within Pmga was tested . A purified fusion of Mga to the C-terminal end of maltose-binding protein (MBP-Mga), encoded by malE-mga, was shown previously to bind to the promoter regions of Mga-regulated genes, including scpA and emm . We report here that MBP-Mga can function in vivo to regulate emm and mga . Electrophoretic mobility shift assays and DNase I footprinting were used to demonstrate specific binding of MBP-Mga to two ca . 59-bp binding sites in Pmga centered around bases -108 and -180 from the major P2 start of transcription . Mga binding sites from Pemm and PscpA were shown to compete for binding at the two Pmga sites, suggesting that the same domain of Mga interacts at all of these promoter targets . Deletion of the distal Pmga binding site (site I) in vivo resulted in loss of Mga-dependent transcription from the P2 start . However, the same lesion resulted in an increase in P1 transcription that was independent of Mga . This suggests the existence of a repressor of mga transcription with a binding site overlapping those of Mga.

J Bacteriol, 1999 Sep, 181(17), 5355 - 64
Comparative genetics of capsular polysaccharide biosynthesis in Streptococcus pneumoniae types belonging to serogroup 19; Morona JK et al.; The genetic basis for the structural diversity of capsule polysaccharide (CPS) in Streptococcus pneumoniae serogroup 19 (consisting of types 19F, 19A, 19B, and 19C) has been determined for the first time . In this study, the genetic basis for the 19A and 19C serotypes is described, and the structures of all four serogroup 19 cps loci and their flanking sequences are compared . Transformation studies show that the structural difference between the 19A and 19F CPSs is likely to be a consequence of differences between their respective polysaccharide polymerase genes (cps19aI and cps19fI) . The CPS of type 19C differs from that of type 19B by the addition of glucose . We have identified a single gene difference between the two cps loci (cps19cS), which is likely to encode a glucosyl transferase . The arrangement of the genes within the cps19 loci is highly conserved, with 13 genes (cps19A to -H and cps19K to -O) common to all four serogroup 19 members . These cps genes encode functions required for the synthesis of the shared trisaccharide component of the group 19 CPS repeat unit structures . Furthermore, the genetic differences between the group 19 cps loci identified are consistent with the CPS structures of the individual serotypes . Functions have been assigned to nearly all of the cps19 gene products, based on either gene complementation or similarity to other proteins with known functions, and putative biosynthetic pathways for production of all four group 19 CPSs have been proposed.

J Bacteriol, 1999 Sep, 181(17), 5242 - 9
16S rRNA is bound to era of Streptococcus pneumoniae; Meier TI et al.; Era is an essential membrane-associated GTPase that is present in bacteria and mycoplasmas . Era appears to play an important role in the regulation of the bacterial cell cycle . In this study, we expressed the native and glutathione S-transferase (GST) fusion forms of Streptococcus pneumoniae Era in Escherichia coli and purified both proteins to homogeneity . We showed that RNA was copurified with the GST-Era protein of S . pneumoniae during affinity purification and remained associated with the protein after removal of the GST tag by thrombin cleavage . The thrombin-treated and untreated GST-Era proteins could bind and hydrolyze GTP and exhibited similar kinetic properties (dissociation constant {kD}, Km, and Vmax) . However, the native Era protein purified by using different chromatographic columns had a much lower GTPase activity than did GST-Era, although it had a similar k(D) . In addition, RNA was not associated with the protein . Purified GST-Era protein was shown to be present as high (600-kDa)- and low (120-kDa)-molecular-mass forms . The high-molecular-mass form of GST-Era was associated with RNA and exhibited a very high GTPase activity . Approximately 40% of purified GST-Era protein was associated with RNA, and removal of the RNA resulted in a significant reduction in GTPase activity . The RNA associated with GST-Era was shown to be predominantly 16S rRNA . The native Era protein isolated directly from S . pneumoniae was also present as a high-molecular-mass species (600 kDa) complexed with RNA . Together, our results suggest that 16S rRNA is associated with Era and might stimulate its GTPase activity.

J Bacteriol, 1999 Sep, 181(17), 5176 - 84
Molecular characterization of type-specific capsular polysaccharide biosynthesis genes of Streptococcus agalactiae type Ia; Yamamoto S et al.; The type-specific capsular polysaccharide (CP) of a group B streptococcus, Streptococcus agalactiae type Ia, is a high-molecular-weight polymer consisting of the pentasaccharide repeating unit 4)-{alpha-D-NeupNAc-(2-->3)-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1- ->3 )}-beta-D-Galp-(1-->4)-beta-D-Glcp-(1 . Here, cloning, sequencing, and transcription of the type Ia-specific capsular polysaccharide synthesis (cps) genes and functional analysis of these gene products are described . A 26-kb DNA fragment containing 18 complete open reading frames (ORFs) was cloned . These ORFs were designated cpsIaA to cpsIaL, neu (neuraminic acid synthesis gene) A to D, orf1 and ung (uracil DNA glycosylase) . The cps gene products of S . agalactiae type Ia were homologous to proteins involved in CP synthesis of S . agalactiae type III and S . pneumoniae serotype 14 . Unlike the cps gene cluster of S . pneumoniae serotype 14, transcription of this operon may start from cpsIaA, cpsIaE, and orf1 because putative promoter sequences were found in front of these genes . Northern hybridization, reverse transcription-PCR, and primer extension analyses supported this hypothesis . DNA sequence analysis showed that there were two transcriptional terminators in the 3' end of this operon (downstream of orf1 and ung) . The functions of CpsIaE, CpsIaG, CpsIaI, and CpsIaJ were examined by glycosyltransferase assay by using the gene products expressed in Escherichia coli JM109 harboring plasmids containing various S . agalactiae type Ia cps gene fragments . Enzyme assays suggested that the gene products of cpsIaE, cpsIaG, cpsIaI, and cpsIaJ are putative glucosyltransferase, beta-1, 4-galactosyltransferase, beta-1,3-N-acetylglucosaminyltransferase, and beta-1,4-galactosyltransferase, respectively.

Microbiology, 1999 Aug, 145 ( Pt 8), 2023 - 31
Serotype 14 variants of the Spanish penicillin-resistant serotype 9V clone of Streptococcus pneumoniae arose by large recombinational replacements of the cpsA-pbp1a region; Coffey TJ et al.; The high prevalence of penicillin resistance among Streptococcus pneumoniae isolates from Uruguay has been associated with the emergence of a penicillin-resistant clone of serotype 14 . Isolates of this clone were identical by multilocus sequence typing to members of the Spanish penicillin-resistant serotype 9V clone and possessed indistinguishable forms of the penicillin-binding protein 2b and 2x genes . Their pbp1a genes were also identical, except at the 3' end . The serotype 14 isolates were shown to be a variant of the Spanish serotype 9V clone which arose by a 22.2 kb recombinational replacement that introduced the capsular biosynthetic locus, and part of the neighbouring pbp1a gene, from a serotype 14 isolate . One end of the recombinational replacement was within the first gene of the capsular polysaccharide operon, cpsA, as the sequence of the upstream dexB gene, through most of cpsA, was identical in the penicillin-resistant serotype 9V and 14 isolates, but the sequences differed in the rest of cpsA and in cpsB . The other recombinational junction was at the end of the divergently transcribed pbp1a gene, which is approximately 11.6 kb downstream of the capsular biosynthetic locus . Isolates of this serotype variant were also detected in Spain and Denmark . Penicillin-resistant serotype 14 isolates from Poland were also closely related to the penicillin-resistant serotype 9V clone, but have emerged independently, as one end of the recombinational replacement was upstream of dexB and the other was within pbp1a, but at a different position from that in the serotype 14 variants from Uruguay, Spain and Denmark . Serotype 14 variants of the Spanish serotype 9V clone have therefore arisen on more than one occasion by large recombinational replacements that extend from the start of the cps region into the pbp1a gene.

Microbiology, 1999 Aug, 145 ( Pt 8), 1859 - 69
Genetic and physiological studies of the CiaH-CiaR two-component signal-transducing system involved in cefotaxime resistance and competence of Streptococcus pneumoniae; Giammarinaro P et al.; A mutation in the ciaH gene of Streptococcus pneumoniae induces cefotaxime resistance and transformation deficiency . ciaH encodes a putative sensor protein that belongs to the family of signal-transducing histidine kinases . This gene is adjacent to ciaR, which encodes a DNA-binding protein involved in the regulation of genes responding to environmental signals sensed by the histidine kinase . The authors have characterized a mutation that induces reversion of both cefotaxime resistance and transformation deficiency . It is a T/A deletion in the ciaR gene resulting in the synthesis of a truncated protein containing only 125 amino acids instead of 224 . The ciaH mutation requires a functional CiaR protein for expression . Northern blot analysis, using ciaR-ciaH as a probe, revealed one mRNA from the wild-type strain, indicating that the two genes constitute an operon . Comparisons of Northern blots show that the operon is constitutively activated in the strain carrying only the ciaH mutation . In the wild-type strain the activation occurs when the Ca2+ concentration is very low, demonstrating that Ca2+ is the environmental signal . The pleiotropic effects caused by the ciaH mutation include sensitivity to antibiotics and toxins, the ability to form protoplasts and the susceptibility to lysis with deoxycholate . Null-mutants were constructed in both genes and the particular features of the ciaR null mutant determined . It is able to grow in choline-deprived medium, and competence development occurs in a phosphate-deprived competence medium (CH-maleate), suggesting that the CiaH-CiaR system regulates several pathways, including teiochoic acid synthesis.

Commun Dis Public Health, 1999 Jan, 2(1), 64 - 5
Surveillance of neonatal group B streptococcal infection in Sunderland; Bignardi GE; Surveillance of neonatal group B streptococcus infection in Sunderland identified 15 confirmed cases (with positive cultures from blood or CSF) in three years from 1995 to 1997, equivalent to an incidence of 1.42 per 1000 live births, not much lower than the estimate of 1.8 used in the United States to justify the introduction of preventative policies . Confirmed early-onset cases may represent only a fraction of the true number of cases, and a modified risk factor-based policy was introduced in Sunderland in June 1998.

Caries Res, 1999 Sep-Oct, 33(5), 393 - 400
Effect of Apis mellifera propolis from two Brazilian regions on caries development in desalivated rats; Koo H et al.; The purpose of the present study was to evaluate the effect of Apis mellifera propolis collected from two regions of Brazil on caries development in desalivated rats . Ethanolic extracts of propolis (EEP) were prepared from crude propolis samples collected in Minas Gerais state (MG), southeastern Brazil, and Rio Grande do Sul state (RS), southern Brazil . The flavonoid composition of EEP was analyzed by high-performance thin-layer chromatography (HPTLC) and reversed-phase high-performance liquid chromatography (HPLC) . For the animal study, 30 specific pathogen-free Wistar rats were infected with Streptococcus sobrinus 6715 and surgically desalivated . The rats were randomly divided into three groups which were treated with 80% ethanol (control), EEP from MG and EEP from RS . The animals were placed in a Konig-Hofer programmed feeder and received 17 meals of diet 2000 daily at hourly intervals . The solutions were applied on the rat molars (25 microl on molars of each quadrant) twice a day, by using graduate syringes . After 3 weeks, the animals were killed by CO(2) asphyxiation . For microbial assessment, the left jaw was removed and sonicated in 154 mM NaCl solution . Dental caries was evaluated according to Larson's modification of Keyes' system . The HPTLC patterns and HPLC profiles demonstrated that both quality and quantity of flavonoid aglycones of EEP from MG were different compared to EEP from RS . In general, it is apparent that EEP from RS contained the highest concentrations of pinocembrin, chrysin, acacetin and galangin . The group of animals treated with EEP from RS showed the lowest smooth-surface and sulcal caries scores as well as less caries severity in smooth-surface and sulcal lesions, and these data were statistically different when compared with the control group . The group treated with EEP from MG only demonstrated a significant difference in the severity of sulcal lesions when compared to the control group . The percentage of S . sobrinus was lower in the groups treated with EEP, but did not differ statistically from the control group . The results showed that the cariostatic effect of propolis depends on its composition, and consequently the region of collection of propolis samples.

Caries Res, 1999 Sep-Oct, 33(5), 366 - 71
Inhibitory effect of antibacterial resin composite against Streptococcus mutans; Tanagawa M et al.; Dental resin composites with antibacterial activity may be useful for preventing the secondary caries frequently seen around restorations . Three types of silver-supported antibacterial materials (Novaron, Amenitop and AIS) inhibited the growth of the major oral pathogen Streptococcus mutans . Minimum inhibitory amounts in suspensions of Novaron, Amenitop and AIS against S . mutans were 40, 30 and 400 microg/ml, respectively . These antibacterial materials were incorporated into TEGDMA-UDMA-based light-activated resin composite, and the antibacterial activities of these composites were examined . Composites incorporating 5 wt% (N-5) or more of Novaron and 7 wt% (AM-7) or more of Amenitop inhibited the growth of S . mutans, whereas composites incorporating up to 10 wt% of AIS did not . No significant difference in either compressive or flexural strength was observed between the control and N-5 composites after 1 day and 6 months of storage in water . However, for AM-5 composite, there was a significant difference in either strength parameter between the two immersion periods . There was no or extremely little release of silver ions from the N-5 and AM-5 composites after 1 day or 6 months of immersion in water . These results indicated that a light-activated resin composite incorporating silver-supported antibacterial material such as Novaron may be clinically useful due to its inhibitory effect against S . mutans and favorable mechanical properties.

Int J Infect Dis, 1999 Spring, 3(3), 147 - 52
Severe pneumococcal infection at a Thai hospital; Leelarasamee A et al.; OBJECTIVES: To determine clinical manifestations, prognostic factors, and therapeutic outcomes of severe pneumococcal infection . METHODS: Hospitalized patients with specimens cultured positive for Streptococcus pneumoniae were identified retrospectively by reviewing hospital records from 1992 to May 1998 at Siriraj Hospital . RESULTS: Of 205 evaluable cases, 130 (63.4%) patients were male . Nineteen (9.3%) patients were less than 2 years old, 29 (14.1%) were between 2 and 13 years, 99 (48.3%) were between 14 and 60 years, and 58 (28.3%) were over 60 years of age . From 1992 to 1997, the average admission rate was highest (36.4%) between January and March (range = 20-45%) . Average admission rates during other periods ranged from 20.0% to 23.1% . Pneumonia (50.7%) and acute exacerbation of chronic obstructive pulmonary disease or infected bronchiectasis or bronchopneumonia (21.0%) were the most frequent diagnoses, followed by meningitis (14.6%) and primary sepsis without localized lesion (8 . 3%) . The mortality rate during the first 7 days of hospitalization was 28.8%, and thereafter, 11.7% . The odds ratios (95% CI) of old age, congestive heart failure, and alcoholism for death were 3.4 (1 . 4-8.2), 8.6 (0.97-76.1), and 8.0 (3.1-20.9), respectively . For pneumonitis only, mortality rates among alcoholic and nonalcoholic patients were 76.9% and 39.6%, respectively (P = 0.025) . CONCLUSIONS: Patients who were alcoholic, over 60 years of age, or had congestive heart failure were vulnerable to severe pneumococcal infection with significant mortality, in spite of proper selection of empirical antimicrobials . Diabetes mellitus and multiple myeloma also contributed to late mortality after 7 days of hospitalization.

Diagn Microbiol Infect Dis, 1999 Aug, 34(4), 315 - 20
Antimicrobial activity of gatifloxacin (AM-1155, CG5501), and four other fluoroquinolones tested against 2,284 recent clinical strains of Streptococcus pneumoniae from Europe, Latin America, Canada, and the United States . The SENTRY Antimicrobial Surveillance Group (Americas and Europe); Odland BA et al.; The newer fluoroquinolones generally have greater potency against Gram-positive cocci including Streptococcus pneumoniae . In this study, we report the activity of gatifloxacin (formerly AM-1155 or CG5501) compared with penicillin, erythromycin, and four other peer drugs, tested against 2284 strains isolated in North America (Canada and United States), Latin America (six nations), and Europe in 1997 . Reference broth microdilution methods were used and results were interpreted by consensus standards . Gatifloxacin demonstrated uniform potency against pneumococci across all monitored geographic areas (MIC90, 0.5 microgram/mL; > or = 99.6% of strains inhibited at < or = 1 microgram/mL) . This activity was comparable to trovafloxacin (MIC90, 0.5 microgram/mL) and sparfloxacin (MIC90, 0.5 microgram/mL) and two- to four-fold greater than that of ciprofloxacin or levofloxacin . The most resistant strains to the fluoroquinolones had mutations in both par C (Ser 79-->Phe) and gyr A (Ser83-->Lys or Phe) . Penicillin resistance (MIC, > or = 0.12 microgram/mL) rates varied from 27.6% in Europe to 55.7% in Latin America . Macrolide resistance was greatest in Europe and the United States . Gatifloxacin appears to be a promising new fluoroquinolone for clinical use in respiratory tract infections commonly caused by S . pneumoniae.

Diagn Microbiol Infect Dis, 1999 Aug, 34(4), 275 - 80
Evaluation of the Strep A OIA assay versus culture methods: ability to detect different quantities of group A Streptococcus; Kuhn S et al.; The Strep A OIA assay by Biostar (Boulder, Co., USA) is a unique optical immunoassay system for the rapid detection of Group A streptococcal carbohydrate . As part of a community-based pediatric cohort study of Group A Streptococcus (GAS) persistence following antibiotic therapy of pharyngitis, the performance of the Strep A OIA assay was compared with the amount of growth from standard throat swab culture methods . A total of 363 throat swabs taken over the course of the study was evaluated from 248 children between 2 and 18 years of age . Two culture methods were performed: an agar plate with the throat swab using Columbia agar base with 5% sheep blood incubated under an anaerobic environment for 48 h and Todd-Hewitt broth (THB) enhancement . The Strep A OIA was then performed . A total of 144 of 363 (39.7%) samples was positive for GAS by one or more of the laboratory tests across study visits: agar culture detected 132 of 144 (91.7%), THB culture detected 128 of 144 (88.9%), and the Strep A OIA assay detected 129 of 144 (89.6%) . Complete agreement among all three laboratory tests was found for 333 of 363 (91.7%) of the samples . Agar culture results were comparable to THB cultures with a sensitivity of 96.9%, specificity of 96.6%, a positive predictive value of 93.9%, and a negative predictive value of 98.3% . Although the performance of the Strep A OIA assay had similar specificity (96.5%) and positive predictive value (93.8%) compared with the combined results of the two culture methods, the sensitivity (89.0%) and negative predictive value (93.6%) were lower . A significant difference (p < 0.001) was found in the ability of the Strep A OIA assay to detect agar culture-positive swabs that had a light growth (1+ or 2+) (63.0%) versus a moderate (3+) or heavy (4+) growth (98.1%) of GAS . Although the Strep A OIA assay allows GAS throat swab results to be reported an average of 24 h sooner than either of the cultures, the rapid assay was not as sensitive in detecting light growth GAS-positive cultures.

Eur J Immunol, 1999 Aug, 29(8), 2414 - 9
The role of calcium homeostasis and flux during bacterial antigen processing in murine macrophages; Delvig AA et al.; We report that MHC class II (MHC-II)-restricted antigen processing of two CD4(+) T cell epitopes from the surface M protein of Streptococcus pyogenes in murine macrophages is dependent on intact calcium homeostasis and flux . We have previously shown that the CD4(+) T cell epitope 308-319 of the type 5 M protein is presented by newly synthesized MHC-II molecules via the classical pathway, while 17-31 is loaded on recycling MHC-II molecules via the recycling pathway . In this report we show that processing of viable bacteria for 308-319 presentation depended on the availability of intra- and extra cellular calcium, intact gadolinium-sensitive and/or T-type calcium channels, as well as on thapsigargin-sensitive homeostasis of intracellular calcium . In contrast, processing of 17-31 was independent of both intracellular calcium and gadolinium-sensitive calcium channels . The data suggest that alternative antigen processing pathways have different requirements for intracellular calcium homeostasis.

Infect Immun, 1999 Sep, 67(9), 4814 - 8
Antiphosphorylcholine antibody levels are elevated in humans with periodontal diseases; Schenkein HA et al.; Human immunoglobulin G2 (IgG2) serum concentrations and the IgG2 antibody response to Actinobacillus actinomycetemcomitans can be influenced by genes, by environmental factors such as smoking, and by periodontal disease status . Examination of the IgG2 response to phosphorylcholine (PC), a response thought to be mainly induced by the C polysaccharide of Streptococcus pneumoniae, suggested that periodontal disease status was also associated with this response . This prompted the hypothesis that PC is an important oral antigen associated with organisms in the periodontal flora and that anti-PC antibody is elevated as a consequence of periodontal disease . Subjects in various periodontal disease diagnostic categories in which attachment loss is exhibited were tested for anti-PC in serum . Those with adult periodontitis, localized juvenile periodontitis, generalized early-onset periodontitis, and gingival recession all had similar levels of anti-PC IgG2 serum antibody which were significantly greater than in the group of subjects with no attachment loss . Analysis of plaque samples from subgingival and supragingival sites in all diseases categories for reactivity with the anti-PC specific monoclonal antibody TEPC-15 revealed that a substantial proportion of the bacteria in dental plaque (30 to 40%) bear PC antigen; this antigen was not restricted to morphotypes resembling only cocci but was also present on rods and branched filamentous organisms . We found that S . mitis, S . oralis, and S . sanguis, as well as oral actinomycetes, including A . viscosus, A . odontolyticus, and A . israelii, incorporated substantial amounts of {(3)H}choline from culture media . Further analysis of antigens derived from these organisms by Western blot indicated that S . oralis, S . sanguis, A . viscosus, A . odontolyticus, and A . israelii contained TEPC-15-reactive antigens . The data show that many commonly occurring bacterial species found in dental plaque contain PC antigen and that immunization with plaque-derived PC antigens as a consequence of inflammation and periodontal attachment loss may influence systemic anti-PC antibody concentrations.

Infect Immun, 1999 Sep, 67(9), 4720 - 4
Pneumococcal surface protein A inhibits complement activation by Streptococcus pneumoniae; Tu AH et al.; Pneumococcal surface protein A (PspA) is a surface-exposed protein virulence factor for Streptococcus pneumoniae . In this study, no significant depletion of serum complement was observed for the serum of mice infected with pneumococci that express PspA . In contrast, in mice infected with an isogenic strain of pneumococci lacking PspA, significant activation of serum complement was detected within 30 min after infection . Also, the PspA-deficient strain but not the PspA-expressing strain was cleared from the blood within 6 h . The contribution of PspA to pneumococcal virulence was further investigated by using mice deficient for C5, C3, or factor B . In mice deficient for C3 or factor B, PspA-negative pneumococci became fully virulent . In contrast, in C5-deficient mice as in wild-type mice, PspA-deficient pneumococci were avirulent . These in vivo data suggest that, in nonimmune mice infected with pneumococci, PspA interferes with complement-dependent host defense mechanisms mediated by factor B . Immunoblots of pneumococci opsonized in vitro suggested that more C3b was deposited on PspA-negative than on PspA-positive pneumococci . This was observed with and without anticapsular antibody . Furthermore, processing of the alpha chain of C3b was reduced in the presence of PspA . We propose that PspA exerts its virulence function by interfering with deposition of C3b onto pneumococci and/or by inhibiting formation of a fully functional alternative pathway C3 convertase . By blocking recruitment of the alternative pathway, PspA reduces the amount of C3b deposited onto pneumococci, thereby reducing the effectiveness of complement receptor-mediated pathways of clearance.

Infect Immun, 1999 Sep, 67(9), 4693 - 9
Regulation of protein phosphorylation and pathogen phagocytosis by surfactant protein A; Schagat TL et al.; Surfactant protein A (SP-A), a pulmonary member of the collectin family of proteins, facilitates the rapid clearance of pathogens by upregulating immune cell functions in the lungs . SP-A binds to bacteria and targets them for rapid phagocytosis by alveolar macrophages, but the mechanism by which this stimulation occurs is not clear . To characterize the intracellular events that may be involved, we examined the roles of protein phosphorylation and cytoskeletal polymerization in SP-A-stimulated phagocytosis . In rat alveolar macrophages, SP-A stimulated rapid tyrosine phosphorylation of specific proteins in a dose- and time-dependent manner . The pattern of proteins that were phosphorylated in response to SP-A, as resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was similar to that observed for immunoglobulin G (IgG)-stimulated macrophages . Both SP-A and IgG stimulated increases in phagocytosis of Streptococcus pneumoniae above levels in the absence of added protein by 394% +/- 81% and 200% +/- 25%, respectively . Phagocytosis in both cases was dependent on tyrosine kinases, protein kinase C, and actin polymerization but not on microtubule activity . These studies show that SP-A utilizes pathways similar to those used by IgG to increase macrophage phagocytosis of bacteria.

Infect Immun, 1999 Sep, 67(9), 4646 - 54
Heat-killed Streptococcus suis capsular type 2 strains stimulate tumor necrosis factor alpha and interleukin-6 production by murine macrophages; Segura M et al.; Streptococcus suis capsular type 2 is an important etiological agent of swine meningitis, and it is also a zoonotic agent . Since mononuclear phagocytes have been suggested to play a central role in the pathogenesis of meningitis, the objective of the present study was to evaluate the capacity of whole killed S . suis type 2 organisms to induce the release of the proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) by murine macrophages . Induction of cytokines was evaluated in the presence or absence of phorbol ester (phorbol 12-myristate 13-acetate {PMA}) costimulation . Results showed that S . suis type 2 stimulated the production of both cytokines in a concentration- and time-dependent fashion . Although large doses of bacteria were required for maximal cytokine release, titers were similar to those obtained with the lipopolysaccharide (LPS) positive control . An increase in cytokine release was observed with both S . suis and LPS with PMA costimulation . Experiments with cytochalasin-treated macrophages showed that the stimulation of cytokine production was phagocytosis independent . When macrophages were stimulated with an unencapsulated mutant, an increase in TNF production was observed, but the absence of the capsule had no effect on IL-6 production . In fact, whereas purified capsular polysaccharide of S . suis failed to induce cytokine release, purified S . suis cell wall induced both TNF and, to a lesser extent, IL-6 . IL-6 secretion probably requires some distinct stimuli which differ from those of TNF . Finally, the S . suis putative virulence factors suilysin and extracellular protein EF showed no cytokine-stimulating activity . The ability of S . suis to trigger macrophages to produce proinflammatory cytokines may have an important role in the initiation and development of meningitis caused by this microorganism.

Infect Immun, 1999 Sep, 67(9), 4551 - 6
The autolysin-encoding gene (lytA) of Streptococcus pneumoniae displays restricted allelic variation despite localized recombination events with genes of pneumococcal bacteriophage encoding cell wall lytic enzymes; Whatmore AM et al.; The lytA-encoded autolysin (N-acetylmuramoyl-L-alanine amidase) of Streptococcus pneumoniae is believed to play an important role in the pathogenesis of pneumococcal infection and has been identified as a putative vaccine target . Allelic diversity of lytA in an extensive collection of clinical isolates was assessed by restriction fragment length polymorphism and confirmatory sequencing studies . Genetic diversity within lytA is limited, especially compared to the high levels of diversity seen in other pneumococcal virulence factor genes, although small blocks generating mosaic structure were identified . Sequence comparisons with genes encoding cell wall lytic enzymes of pneumococcal bacteriophage suggest that localized recombination events have occurred between host lytA and these bacteriophage genes . These results confirm earlier suggestions that recombination between DNA encoding bacteriophage autolytic enzymes and chromosomally encoded lytA might be important in the evolution of lytA . The implications of these findings for understanding the evolution of lytA and the potential utility of LytA as a vaccine target are discussed.

Infect Immun, 1999 Sep, 67(9), 4545 - 50
Role of tumor necrosis factor alpha, interleukin-1beta, and interleukin-6 in a mouse model of group B streptococcal arthritis; Tissi L et al.; Intravenous inoculation of CD1 mice with 10(7) CFU of type IV group B Streptococcus (GBS IV) results in a high incidence of diffuse septic arthritis . In this study the roles of tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 in articular pathology were evaluated . Cytokine levels were quantified in the serum and joints by enzyme-linked immunosorbent assay in mice injected with GBS IV and tested or not tested with pentoxifylline (PTF), a methylxanthine that affects cytokine production . PTF was administered intraperitoneally at a dose of 1 mg/mouse (50 mg/kg of body weight) 1 h after GBS infection and then at 24-h intervals for 4 days . High levels of IL-1beta and IL-6, but not TNF-alpha, were detected in the joints of mice injected with GBS IV from 5 to 15 days after infection, when articular lesions were most frequent and severe . IL-1beta and IL-6 concentrations in the joints significantly (P < 0.001) exceeded those detected in the serum, confirming a strong local production . PTF treatment resulted in a strong reduction of cytokine production and in a marked decrease in both the incidence and severity of arthritis . Inoculation of exogenous murine recombinant IL-1beta or IL-6 in mice treated with GBS IV plus PTF resulted in an incidence and severity of articular lesions similar to those obtained with inoculation of GBS IV alone . No significant effect was obtained with TNF-alpha administration . These data show a strong involvement of IL-1beta and IL-6, but not TNF-alpha, in the pathogenesis of GBS arthritis.

Infect Immun, 1999 Sep, 67(9), 4517 - 24
Resistance to both complement activation and phagocytosis in type 3 pneumococci is mediated by the binding of complement regulatory protein factor H; Neeleman C et al.; To study the role of surface-associated proteins in the virulence of Streptococcus pneumoniae, we used two serotype 3 strains, ATCC 6303 and WU2, and two PspA-negative mutants of WU2, an encapsulated one, JY1123 (Caps(+)/PspA(-)), and an unencapsulated one, DW3.8 (Caps(-)/PspA(-)) . ATCC 6303 and WU2 were highly virulent in mice, while the virulence of JY1123 was slightly decreased (50% lethal doses {LD(50)s}, 24, 6, and 147 CFU/mouse, respectively); DW3.8 was avirulent (LD(50), 2 x 10(8) CFU) . In vitro, ATCC 6303, WU2, and JY1123 (Caps(+)/PspA(-)) strongly resisted complement activation and complement-dependent opsonophagocytosis, whereas DW3.8 (Caps(-)/PspA(-)) was easily phagocytized in fresh serum . Trypsin treatment of ATCC 6303, WU2, and JY1123 (Caps(+)/PspA(-)) resulted in enhanced complement activation and complement-dependent opsonophagocytosis . Trypsin had no deleterious effect on the polysaccharide capsule . In addition, trypsin pretreatment of ATCC 6303 strongly reduced virulence upon intraperitoneal challenge in mice . This indicated that surface proteins play a role in the resistance to complement activation and opsonophagocytosis and contribute to the virulence of type 3 pneumococci . In subsequent experiments, we could show that the modulation of complement activation was associated with surface components that bind complement regulator factor H; binding is trypsin sensitive and independent of prior complement activation . Immunoblotting of cell wall proteins of the virulent strain ATCC 6303 with anti-human factor H antibody revealed three factor H-binding proteins of 88, 150, and 196 kDa . Immunogold electron microscopy showed a close association of factor H-binding components with the outer surface of the cell wall . The role of these factor H-binding surface proteins in the virulence of pneumococci is interesting and warrants further investigation.

Infect Immun, 1999 Sep, 67(9), 4510 - 6
Stress-induced membrane association of the Streptococcus mutans GTP-binding protein, an essential G protein, and investigation of its physiological role by utilizing an antisense RNA strategy; Baev D et al.; SGP (for Streptococcus GTP-binding protein) is a Streptococcus mutans essential GTPase which has significant sequence identity to the previously identified Escherichia coli Era protein and to numerous other prokaryotic GTPase proteins of unknown function . Recent studies in our laboratory have addressed the possible role of SGP in the stress response of the oral pathogen S . mutans . Here we report that during growth in the early stationary phase, and in response to elevated temperatures or acidic pH, the distribution of SGP between the cytoplasm and the membranes of S . mutans cells varies . Immunoblot analysis of soluble and membrane protein fractions collected from the mid-log and early stationary growth phases of bacterial populations grown at normal temperature (37 degrees C) and at the elevated temperature of 43 degrees C, or at acidic pH, demonstrated that the total amount of SGP increased with the age of the bacterial culture, elevated temperature, or acidic pH . Furthermore, it was established that a substantial amount of SGP is associated with the membrane fraction under stress conditions . In order to investigate the physiological role of SGP, we constructed an S . mutans strain capable of chromosomal sgp antisense RNA expression, which interferes with the normal information processing of the sgp gene . Utilizing this strain, we determined conditions whereby the streptococcal cells can be depleted of SGP, thus avoiding the problem of constructing a conditional lethal system . From the results of measurements of the nucleotide pools extracted from the antisense strain and its isogenic counterpart, we propose that one of the physiological roles of SGP is regulation and modulation of the GTP/GDP ratio under different growth conditions . Moreover, we observed that in SGP-depleted cells the levels of glucan-binding protein A (GbpA) substantially increased, suggesting that GbpA may have stress response-related physiological functions . Finally, the potential applications of the antisense RNA approach that we employed are discussed.

Infect Immun, 1999 Sep, 67(9), 4334 - 9
Group A Streptococcus induces apoptosis in human epithelial cells; Tsai PJ et al.; Internalization of group A streptococcus (GAS) by epithelial cells may have a role in causing invasive diseases . The purpose of this study was to examine the fate of GAS-infected epithelial cells . GAS has the ability to invade A-549 and HEp-2 cells . Both A-549 and HEp-2 cells were killed by infection with GAS . Epithelial cell death mediated by GAS was at least in part through apoptosis, as shown by changes in cellular morphology, DNA fragmentation laddering, and propidium iodide staining for hypodiploid cells . A total of 20% of A-549 cells and 11 to 13% of HEp-2 cells underwent apoptosis after 20 h of GAS infection, whereas only 1 to 2% of these cells exhibited spontaneous apoptosis . We further examined whether streptococcal pyrogenic exotoxin B (SPE B), a cysteine protease produced by GAS, was involved in the apoptosis of epithelial cells . The speB isogenic mutants had less ability to induce cell death than wild-type strains . When A-549 cells were cocultured with the mutant and SPE B for 2 h, the percentage of apoptotic cells did not increase although the number of intracellular bacteria increased to the level of wild-type strains . In addition, apoptosis was blocked by cytochalasin D treatment, which interfered with cytoskeleton function . The caspase inhibitors Z-VAD.FMK, Ac-YVAD.CMK, and Ac-DEVD.FMK inhibited GAS-induced apoptosis . These results demonstrate for the first time that GAS induces apoptosis of epithelial cells and internalization is required for apoptosis . The caspase pathway is involved in GAS-induced apoptosis, and the expression of SPE B in the cells enhances apoptosis.

Infect Immun, 1999 Sep, 67(9), 4326 - 33
Fibrinogen cleavage by the Streptococcus pyogenes extracellular cysteine protease and generation of antibodies that inhibit enzyme proteolytic activity; Matsuka YV et al.; The extracellular cysteine protease from Streptococcus pyogenes is a virulence factor that plays a significant role in host-pathogen interaction . Streptococcal protease is expressed as an inactive 40-kDa precursor that is autocatalytically converted into a 28-kDa mature (active) enzyme . Replacement of the single cysteine residue involved in formation of the enzyme active site with serine (C192S mutation) abolished detectable proteolytic activity and eliminated autocatalytic processing of zymogen to the mature form . In the present study, we investigated activity of the wild-type (wt) streptococcal protease toward human fibrinogen and bovine casein . The former is involved in blood coagulation, wound healing, and other aspects of hemostasis . Treatment with streptococcal protease resulted in degradation of the COOH-terminal region of fibrinogen alpha chain, indicating that fibrinogen may serve as an important substrate for this enzyme during the course of human infection . Polyclonal antibodies generated against recombinant 40- and 28-kDa (r40- and r28-kDa) forms of the C192S streptococcal protease mutant exhibited high enzyme-linked immunosorbent assay titers but demonstrated different inhibition activities toward proteolytic action of the wt enzyme . Activity of the wt protease was readily inhibited when the reaction was carried out in the presence of antibodies generated against r28-kDa C192S mutant . Antibodies produced against r40-kDa C192S mutant had no significant effect on proteolysis . These data suggest that the presence of the NH(2)-terminal prosegment prevents generation of functionally active antibodies and indicate that inhibition activity of antibodies most likely depends on their ability to bind the active-site region epitope(s) of the protein.

Infect Immun, 1999 Sep, 67(9), 4320 - 5
Intranasal immunization with heat-inactivated Streptococcus pneumoniae protects mice against systemic pneumococcal infection; Hvalbye BK et al.; In order to study the mucosal and serum antibody response to polysaccharide-encapsulated bacteria in mice, a preparation of heat-inactivated Streptococcus pneumoniae type 4 was administered, with and without cholera toxin, at various mucosal sites . It appeared that intranasal immunization of nonanesthesized animals was superior to either oral, gastric, or colonic-rectal antigen delivery with regard to the induction of serum immunoglobulin G (IgG) and IgA, as well as saliva IgA antibodies specific for pneumococci . The marked IgA antibody response in feces after intranasal, but not after oral or gastric, immunization is suggestive of a cellular link between the nasal induction site and the distant mucosal effector sites . Intranasal immunization also induced antibodies in serum and in mucosal secretions against type-specific capsular polysaccharide . IgA and IgG antibody levels in pulmonary lavage fluids correlated well with saliva IgA and serum IgG antibodies, respectively . Antibody determinations in pulmonary secretions may therefore be redundant in some cases, and the number of experimental animals may be reduced accordingly . After intraperitoneal challenge with type 4 pneumococci, mice immunized intranasally were protected against both systemic infection and death, even without the use of cholera toxin as a mucosal adjuvant . Thus, an efficient intranasal vaccine against invasive pneumococcal disease may be based on a very simple formulation with whole killed pneumococci.

Infect Immun, 1999 Sep, 67(9), 4307 - 11
Streptococcal pyrogenic exotoxin F (SpeF) causes permeabilization of lung blood vessels; Matsumoto M et al.; Acute respiration distress syndrome (ARDS) is a typical complication in toxic shock-like syndrome (TSLS) caused by Streptococcus pyogenes . An isolated perfused rat lung model was used to identify the causative agent of ARDS in TSLS in this study . Some crude preparations separated from the culture supernatants of S . pyogenes isolates caused rapid increases in the weight of perfused lungs, indicating vascular permeabilization . Six samples from M type 1 and 3 isolates from TSLS and pharyngitis patients showed strong permeabilization activity, whereas preparations from isolates of other M types (although the number of isolates examined was limited) were negative . The active substance was purified to a single band by sodium dodecyl sulfate-polyacrylamide gel electrophoresis using various columns, and the N-terminal amino acid sequence was determined . The resultant sequence of eight amino acids was identical to SpeF (mitogenic factor) . Moreover, the vascular permeabilization activity of the purified band was abolished with anti-SpeF antiserum prepared by immunizing with the purified SpeF . This activity was also neutralized by the antiserum prepared by immunizing with a synthetic peptide derived from the published SpeF sequence . These results suggested that streptococcal SpeF is a major cause of permeabilization of lung blood vessels and sufficient for the pathogenesis of ARDS under the conditions of TSLS caused by S . pyogenes.

J Child Neurol, 1999 Aug, 14(8), 509 - 13
Restricted unilateral Sydenham's chorea: reversible contralateral striatal hypermetabolism demonstrated on single photon emission computed tomographic scanning; Dilenge ME et al.; Sydenham's chorea results from group A streptococcus infection and subsequent generation of antineuronal antibodies directed at the caudate nucleus and putamen . Predominantly bilateral, in up to 30% of cases the chorea can be unilaterally restricted . Imaging studies, both structural (magnetic resonance imaging) and functional (positron emission tomography), in patients with bilateral Sydenham's chorea have suggested reversible striatal abnormalities . Two patients with unilateral Sydenham's chorea are presented . Computed tomographic and magnetic resonance imaging were normal in both . However, hexamethylpropylenamine oxime single photon emission tomographic (HMPAO SPECT) studies demonstrated hypermetabolism in the contralateral basal ganglia . Resolution of symptoms in one of the patients coincided with normalization of the SPECT scan . Thus, unilateral striatal hypermetabolism appears to underlie the contralateral chorea observed . A SPECT scan probably should be included in the work-up of new-onset chorea.

Microb Pathog, 1999 Sep, 27(3), 133 - 43
Recombinant hyaluronate associated protein as a protective immunogen against Streptococcus equi and Streptococcus zooepidemicus challenge in mice; Chanter N et al.; The capsule of Streptococcus equi, the cause of strangles, and Streptococcus zooepidemicus, associated with equine lower airway disease, plays an important role in evasion of phagocytosis by polymorphonuclear leucocytes . It is composed of hyaluronate, making it non-immunogenic . A hyaluronate associated protein (HAP) from S . equisimilis, whose gene has been sequenced {1}, was investigated (a) for its presence in S . equi and S . zooepidemicus and (b) as an immunogen able to interfere with capsule structure and protect against experimental challenge of mice . The purified capsule of S . equi contained a protein of similar molecular mass to the S . equisimilis protein (approximately 53 kDa) . Polymerase chain reaction (PCR) using primers derived from the published sequence of S . equisimilis HAP yielded a product from S . equi and S . zooepidemicus of the expected size and susceptibility to restriction endonucleases . Subcloning of two large in frame StuI/SspI fragments of the HAP gene from S . equi, approximately equivalent to the two halves of the molecule, into the expression vector pGEX-3X yielded only the carboxy half in the correct orientation . This latter recombinant produced a GST fusion protein (HAP-GST) of the expected size that was affinity purified . Antibodies in rabbit antiserum to the native protein in purified hyaluronate reacted strongly in immunoblots with HAP-GST . Antiserum to HAP-GST, when soaked into filter paper strips, caused a diminution of capsule production by S . equi cultured on blood agar . Antiserum added into fresh rabbit blood was not opsonic for S . equi . Immunization with HAP-GST significantly reduced rhinitis in Balb/C mice challenged nasally with S . equi and significantly increased survival time and clearance of bacteria in CBA/CA mice challenged intraperitoneally with S . zooepidemicus .

Ann Otol Rhinol Laryngol, 1999 Aug, 108(8), 769 - 76
Immunohistochemical distribution of extracellular matrix components and keratin in experimentally induced otitis media; Harada T et al.; The distribution of collagen types I, III, and IV and of laminin, fibronectin, and keratin was studied in otitis media experimentally induced by Streptococcus pneumoniae in the chinchilla . The expression of interstitial collagen types I and III and of fibronectin was increased in the subepithelial space that was thickened by inflammation in the acute period of infection . The expression of collagen type IV in the subepithelial space could be seen in the early period . The epithelial cells in the middle ear changed from flat cuboidal to pseudostratified columnar in pneumococcus-inoculated ears, and the number of keratin-positive epithelial cells in the middle ear increased remarkably after infection . These results indicate that changes in epithelial cell differentiation effected by the extracellular matrix correlate with changes in expression of keratin . It is proposed that the extracellular matrix may contribute to tissue repair in the middle ear after bacterial infection by interfering with cell proliferation of epithelial cells and fibroblasts.

Can J Microbiol, 1999 Jun, 45(6), 536 - 9
Subcellular localization of the Streptococcus mutans P1 protein C terminus; Homonylo-McGavin MK et al.; To determine the subcellular location of the Streptococcus mutans P1 protein C-terminal anchor, cell envelope fractionation experiments were conducted in combination with Western immunoblotting, using monoclonal antibody MAb 6-8C specific for an epitope that maps near the C terminus of P1 protein and also a polyclonal antibody preparation directed against the P1 C-terminal 144 amino acids (P1COOH) . P1 protein was detected in cell walls but not the membrane purified from S . mutans cells by the monoclonal antibody . In contrast, P1 protein was not detected in the same cell wall preparation using the anti-P1COOH polyclonal antibody . However, proteins released from the cell walls by treatment with mutanolysin contained antigen that was recognized by the anti-P1COOH antibody, suggesting that the epitopes recognized by the antibody were masked by peptidoglycan in the cell wall preparations . When cell walls were treated with boiling trichloroacetic acid to solubilize cell-wall-associated carbohydrate, P1 antigen could not be detected in either the solubilized carbohydrate, or in the remaining peptidoglycan, regardless of whether polyclonal or monoclonal antibody was used . However, when the peptidoglycan was treated with mutanolysin, P1 antigen could be detected in the mutanolysin solubilized fraction by MAb 6-8C . Collectively, these data suggest that the C-terminal 144 amino acids of the P1 protein are embedded within the cell wall, and associated exclusively with the peptidoglycan . Furthermore, the ability of the anti-P1COOH antibody to recognize P1 antigen only after mutanolysin treatment of cell walls suggests these C-terminal 144 amino acids are tightly intercalated within the peptidoglycan strands.

J Immunol, 1999 Sep 1, 163(5), 2761 - 8
Role of complement component C1q in the IgG-independent opsonophagocytosis of group B streptococcus; Butko P et al.; We investigated the role of complement component C1q in the IgG-independent opsonophagocytosis of type III group B Streptococcus (GBS) by peripheral blood leukocytes . We report that C1q binds to type III GBS both in normal human serum deficient in IgG specific for type III capsular polysaccharide and in a low-ionic strength buffer . The dissociation constant Kd ranged from 2.0 to 5.5 nM, and the number of binding sites Bmax ranged from 630 to 1360 molecules of C1q per bacterium (CFU) . An acapsular mutant strain of GBS bound C1q even better than the wild type, indicating that the polysaccharide capsule is not the receptor for C1q . In serum, binding of C1q to GBS was associated with activation of the classical complement pathway . However, normal human serum retained significant opsonic activity after complete depletion of C1q, suggesting that the serum contains a molecule that is able to replace C1q in opsonization and/or complement activation . Mannan-binding lectin, known to share some functions with C1q, appeared not to be involved, since its depletion from serum had little effect on opsonic activity . Excess soluble C1q or its collagen-like fragment inhibited phagocytosis mediated by normal human serum, suggesting that C1q may compete with other opsonins for binding to receptor(s) on phagocytes . We conclude that, although C1q binds directly to GBS, C1q binding is neither necessary nor sufficient for IgG-independent opsonophagocytosis . The results raise the possibility that additional unknown serum factor(s) may contribute to opsonization of GBS directly or via a novel mechanism of complement activation.

Clin Infect Dis, 1999 May, 28(5), 1057 - 61
Use of corticosteroids in glomerulonephritis related to infective endocarditis: three cases and review; Le Moing V et al.; We report the cases of three patients treated for infective endocarditis (IE) for whom corticosteroids were added to the antibiotic treatment . They all had clinical and biological evidence of immune-mediated glomerulonephritis . The microorganisms responsible for IE were Coxiella burnetii, Streptococcus bovis, and Cardiobacterium hominis . Median duration of IE before antimicrobial therapy was 7 months . In all patients, renal function deteriorated despite appropriate antimicrobial treatment for a mean duration of 16 days, but it improved after addition of corticosteroid therapy . All patients were cured of IE . A literature review revealed four additional cases of IE-related glomerulonephritis in which adjunctive immunosuppressive therapy was considered to be effective . Although corticosteroid therapy is generally not recommended for IE, it should be considered for patients whose renal dysfunction secondary to glomerulonephritis does not improve with appropriate antimicrobial treatment, especially if the duration of the illness is long.

Pediatr Med Chir, 1999 Jan-Feb, 21(1), 9 - 12
{Schönlein-Henoch syndrome: clinical-epidemiological analysis of 98 cases}; Sticca M et al.; We analyzed the clinical and epidemiological data of 98 patients (50 males and 48 females) aged between 6 months and 16 years, hospitalized for Schonlein-Henoch syndrome in the last 20 years . The incidence was higher during spring time . Throat culture was positive for streptococcus pyogenes in 16% of patients . 14 of 60 (23%) had a positive allergometric response to various tests . The extrarenal manifestations were: purpura (100%), articular (68%) or gastrointestinal (32%) involvement and orchitis (10%) . Renal symptoms were observed in 23% of the patients, but a clear nephropathy was documented just in 5% of the cases, with resolution within 2 years . Our data suggest, in agreement with the letterature, that renal involvement in Schonlein-Henoch syndrome has usually a benign course.

Clin Infect Dis, 1999 Jun, 28(6), 1265 - 72
A 20-year epidemiological study of pneumococcal meningitis; Stanek RJ et al.; We conducted a retrospective analysis of 55 community-acquired Streptococcus pneumoniae meningitis illnesses in Huntington, West Virginia, from 1978 to 1997 . Fourteen (36.8%) of 38 adults and 2 (11.8%) of 17 children died . Serotypes 6, 23, 3, and 18 accounted for 20 (41.7%) of 48 strains available for serotyping . Of 40 strains available for antimicrobial susceptibility testing, 1 serotype 19 and 1 serotype 23 strain showed intermediate resistance and a second serotype 23 strain showed high resistance to penicillin; all three patients survived . The case-fatality rates among adults who received penicillin alone, gentamicin in combination, or vancomycin and cephalosporin together were 57.1%, 55.5%, and 60%, respectively, and among those who received chloramphenicol or a third-generation cephalosporin, they were 11.1% or nil, respectively . No child died who received chloramphenicol or vancomycin . Two (33%) of 6 children died who received a third-generation cephalosporin; both were critically ill when initially treated . No child and one adult had received pneumococcal vaccine prior to becoming ill.

Clin Infect Dis, 1999 Jun, 28(6), 1206 - 11
Spread of drug-resistant Streptococcus pneumoniae in Asian countries: Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study; Song JH et al.; Antimicrobial susceptibility of 996 isolates of Streptococcus pneumoniae from clinical specimens was investigated in 11 Asian countries from September 1996 to June 1997 . Korea had the greatest frequency of nonsusceptible strains to penicillin with 79.7%, followed by Japan (65.3%), Vietnam (60.8%), Thailand (57.9%), Sri Lanka (41.2%), Taiwan (38.7%), Singapore (23.1%), Indonesia (21.0%), China (9.8%), Malaysia (9.0%), and India (3.8%) . Serotypes 23F and 19F were the most common . Pulsed-field gel electrophoresis (PFGE) of 154 isolates from Asian countries showed several major PFGE patterns . The serotype 23F Spanish clone shared the same PFGE pattern with strains from Korea, Japan, Singapore, Taiwan, Thailand, and Malaysia . Fingerprinting analysis of pbp1a, pbp2x, and pbp2b genes of 12 strains from six countries also showed identical fingerprints of penicillin-binding protein genes in most strains . These data suggest the possible introduction and spread of international epidemic clones into Asian countries and the increasing problems of pneumococcal drug resistance in Asian countries for the first time.

Am J Med, 1999 Jul 26, 107(1A), 86S - 90S
Pneumococcal disease: a symposium in honor of Robert Austrian, MD--a summary; Sanders CV; The Pneumococcus '97 symposium, convened under the direction bf Dr . Stephan L . Kamholz, brought together a preeminent faculty to discuss the current state of our knowledge about Streptococcus pneumoniae and to honor Dr . Robert Austrian, one of the pioneers in the research into what was once one of the primary killers of humankind . My task here is to summarize these diverse presentations and the articles that evolved from them for publication in this supplement to The American Journal of Medicine.

Am J Med, 1999 Jul 26, 107(1A), 69S - 76S
Pneumococcal vaccines: history, current status, and future directions; Butler JC et al.; Streptococcus pneumoniae is the leading cause of community-acquired pneumonia and bacterial meningitis . Although effective antimicrobial drugs have reduced case fatality, the pneumococcus remains a leading global cause of morbidity and mortality . Therefore, prevention of infection by vaccination with the pneumococcal polysaccharide vaccine is recommended for persons at high risk for serious pneumococcal disease, such as the elderly and individuals with certain underlying medical conditions . Pneumococcal polysaccharide vaccines are safe and effective for the prevention of invasive infection among immunocompetent children and adults but are not immunogenic in infants . Conjugation of pneumococcal polysaccharides to a carrier protein improves immune responses among infants, and conjugate vaccines are currently being evaluated in large efficacy trials . The role of pneumococcal conjugate vaccines in adults has not been determined . Pneumococcal vaccines directed against pneumococcal proteins and DNA vaccines that induce anti-pneumococcal antibodies have been evaluated in animal models and may someday provide complementary or alternative methods for preventing pneumococcal infection . Improved utilization of the pneumococcal polysaccharide vaccine and continued development of improved vaccines are essential, and the emergence of drug-resistant strains of S . pneumoniae highlights the importance of preventing pneumococcal infections by vaccination.

Am J Med, 1999 Jul 26, 107(1A), 63S - 68S
Treatment of pneumococcal pneumonia: the case for penicillin G; Bryan CS; Although widely endorsed for specific treatment of pneumococcal pneumonia, penicillin G is seldom used for this purpose in clinical practice for at least three reasons: (1) concern about penicillin-resistant Streptococcus pneumoniae (PRSP) strains; (2) the difficulty of making an early etiologic diagnosis of pneumonia; and (3) lack of a clear consensus about the optimum dosage . Continuous infusion of 20-24 million units of penicillin per day provides serum levels of 16-20 microg/mL in persons with normal renal function . These levels easily exceed the minimum inhibitory concentrations (MICs) of penicillin G against most PRSP strains (4 microg/mL), which are actually strains with reduced susceptibility to penicillin . High-dose penicillin G therapy has not been shown to be therapeutically ineffective against pneumonia due to PRSP strains . However, the extent of penicillin resistance warrants continued monitoring, because strains exhibiting extremely high-level resistance (MIC > or = 8 microg/mL) would probably respond poorly if at all . Development and use of rapid, sensitive, specific ways to diagnose pneumococcal pneumonia could extend the usefulness of penicillin G, thus postponing the emergence of resistance to other antibiotics.

Am J Med, 1999 Jul 26, 107(1A), 50S - 54S
Typing of Streptococcus pneumoniae: past, present, and future; Henrichsen J; Early works leading to the detection of the pneumococcus and eventually to the appreciation that isolates differed in agglutination and that antisera differed in their capacity to protect against pneumococcal infection in the mouse protection test are reviewed . Studies by researchers from Europe, South Africa, and the United States over nearly five decades led to the introduction of serum therapy . Rapid typing methods thus became very important, and type-specific serum therapy generated a dramatic decrease in the number of deaths from pneumococcal pneumonia . Just before the introduction of sulfonamides and, shortly thereafter, penicillin, the use of horse sera was replaced by the use of rabbit sera for a number of reasons . The present methods of typing comprise the capsular reaction test, latex- and coagglutination, and capillary precipitation, to name the most important; these use a large variety of antisera . Newer methods include the use of DNA probes and DNA sequence-based subtyping.

Am J Med, 1999 Jul 26, 107(1A), 44S - 49S
Pneumococcal disease in Sweden: experiences and current situation; Ortqvist A; During the last decade, the incidence of invasive pneumococcal disease in Sweden has risen, seemingly due chiefly to an increasing incidence of pneumococcal bacteremia among the elderly . On the other hand, mortality due to invasive disease in Sweden is low, approximately 10% for bacteremic pneumococcal pneumonia . Beta-lactam resistance in Streptococcus pneumoniae is still a relatively minor problem in Sweden, with only 3%-4% of strains demonstrating decreased susceptibility to penicillin . However, local outbreaks of pneumococcal disease with up to 10% resistance have occurred among children, especially in southern Sweden.

Am J Med, 1999 Jul 26, 107(1A), 28S - 33S
Antimicrobial resistance among clinical isolates of Streptococcus pneumoniae in North America; Barry AL; From a historical perspective, the development of antibiotic resistance among Streptococcus pneumoniae isolates can be traced over the past 3 decades . In North America, penicillin-resistant pneumococci are now found in nearly all medical centers, but the prevalence of such strains varies by region and time period . In the United States, only approximately 75% of all pneumococci are fully susceptible to penicillin, 15% are intermediately susceptible, and approximately 10% are highly resistant . The latter are often multiply resistant to other unrelated drugs, which leaves few effective chemotherapeutic agents with which to treat serious infections caused by such strains . New approaches to therapy are needed to avoid further selection of antibiotic-resistant mutants; these include discontinuing inappropriate or unnecessary use of antibiotics.

Am J Med, 1999 Jul 26, 107(1A), 12S - 27S
Unusual manifestations of invasive pneumococcal infection; Taylor SN et al.; Unusual pneumococcal infections occurred frequently in the preantibiotic age but rapidly declined with the advent of the antibiotic era . Unfortunately, the morbidity and mortality associated with invasive pneumococcal disease remain high despite antibiotic therapy and monumental advances in medical technology . The incidence of invasive pneumococcal disease has increased recently because of the onset of the human immunodeficiency virus (HIV) epidemic and the emergence of antibiotic-resistant pneumococcus . Robert Austrian described the clinical triad of pneumococcal pneumonia, meningitis, and endocarditis, a syndrome that now bears his name . Although seen infrequently today, unusual manifestations of pneumococcal infection such as those Austrian reported still occur . A review of these cases is warranted because, as drug-resistant organisms continue to emerge worldwide, more unusual pneumococcal infections will be seen . Streptococcus pneumoniae is responsible for a remarkable array of disease processes; our literature review uncovered 95 different types of unusual pneumococcal infections representing 2,064 cases . Examples of these infections included pancreatic and liver abscesses, aortitis, gingival lesions, phlegmonous gastritis, inguinal adenitis, testicular and tubo-ovarian abscesses, and necrotizing fasciitis . We also reviewed predisposing underlying illnesses and conditions . Alcoholism, HIV infection, splenectomy, connective tissue disease, steroid use, diabetes mellitus, and intravenous drug use remain common risk factors for invasive pneumococcal infections . Currently, multidrug-resistant S . pneumoniae remains susceptible to vancomycin and several new third-generation fluoroquinolones . As what some fear will be a possible postantibiotic era approaches, clinicians must be able to recognize and manage unusual pneumococcal infections.

Arq Neuropsiquiatr, 1999 Jun, 57(2B), 465 - 70
{Acute bacterial meningoencephalitis in children . Complications and neurologic sequelae}; Natalino W et al.; We studied 271 children under age of 15 with diagnosis of acute bacterial meningencephalitis treated at Medical School in Ribeirao Preto, University of Sao Paulo, between 1980 and 1990 . The patients were divided in two groups: 1) those who had not received previous antibiotics treatment (NTP), with 153 cases; and 2), those who had received previous antibiotics treatment (PT), with 118 cases . The etiological agent was more frequently identified in NPT group, while ventriculitis was more frequent in PT group . Mortality rate accounted for 19.5% of all cases, and 29.7% of children under 12 months of age . Acute meningitis caused by Streptococcus pneumoniae was frequently followed by increased mortality . Convulsive disorders and hemiparesis predominante among children under 12 months of age . On the neurosurgical point of view, ventriculitis, subdural hygroma, hydrocephalus, subdural empyema and brain abscess were identified and treated.

ORL J Otorhinolaryngol Relat Spec, 1999 Jul-Aug, 61(4), 206 - 11
Effects of active immunization with a pneumococcal surface protein (PspA) and of locally applied antibodies in experimental otitis media; White P et al.; An experimental rat model for Streptococcus pneumoniae otitis media was used to investigate passive protection by anti-type 3 capsular antibodies and effects of immunization with pneumococcal surface protein A (PspA) . Anti-type 3 antibodies instilled into the middle ear reduced purulent otitis media as compared to control animals (p = 0.015) . Secondly, after immunization with PspA, the right middle ear was inoculated with S . pneumoniae type 6A in a dose calibrated to induce purulent otitis media . There was an anti-PspA antibody response in all rats immunized and a reduction in signs of purulent otitis media as compared to control animals (p = 0.026) . Thus, purulent (acute) otitis media can be reduced by local application of antibodies in the middle ear and also by immunization with a non-type-specific pneumococcal protein, PspA.

J Clin Microbiol, 1999 Sep, 37(9), 2877 - 81
Immunomagnetic isolation of Streptococcus suis serotypes 2 and 1/2 from swine tonsils; Gottschalk M et al.; Isolation of specific serotypes of Streptococcus suis from the tonsils, nasal cavities, and genital tract is difficult, since low-pathogenic serotypes and untypeable strains also inhabit these sites . An immunomagnetic separation (IMS) technique for the selective isolation of S . suis serotypes 2 and 1/2 was standardized . Superparamagnetic polystyrene beads (immunomagnetic beads or IMB) were coated with either a purified monoclonal antibody (MAb) directed to a capsular sialic acid-containing epitope or purified rabbit immunoglobulin G (polyclonal antibody {PAb}), both specific for S . suis serotypes 2 and 1/2 . The amount of antibodies required for optimum coating of the beads, the number of IMB required for optimum bacterial recovery, and the nonspecific carryover were considerably higher with the MAb-IMS technique than with the PAb-IMS technique . The sensitivity of the IMS technique was 10(1) CFU/0.1 g of tonsil . The presence of serotype 1/2 bacteria did not considerably affect the recovery rate of a serotype 2 strain and vice versa . To validate the technique, PAb-coated beads were used to study 192 tonsils from animals from S . suis serotype 2- or 1/2-infected herds . Results showed that significantly more positive tonsils were detected by the IMS technique than by the standard procedure . This method represents an innovative and highly sensitive approach for the isolation of S . suis serotypes 2 and 1/2 from carrier animals.

J Clin Microbiol, 1999 Sep, 37(9), 2834 - 9
Evidence of clonal dissemination of multidrug-resistant Streptococcus pneumoniae in Hong Kong; Ip M et al.; The relationship between the phenotypic and genotypic characteristics of 105 penicillin-intermediate or -resistant Streptococcus pneumoniae isolates saved during 1994 to 1997 at the Prince of Wales Hospital and Pamela Youde Nethersole Eastern Hospital, Hong Kong, was studied . The pbp genes for penicillin-binding proteins 1a, 2b, and 2x for each isolate were amplified by PCR, and the products were digested with restriction enzymes HinfI and AluI . A combination of the pulsed-field gel electrophoresis (PFGE) profiles, pbp fingerprints, and phenotypic characteristics of capsular types and antibiograms enabled these isolates to be divided into four major groups . Seventy-four percent (78 of 105) of the strains, belonging to serotypes 23F, 19F, and 14, showed indistinguishable pbp fingerprint patterns (group A1, 1-1-1, 1-1-1), with PFGE patterns belonging to group A and its subtypes, suggesting that these strains were closely related . Eighty-three percent (65 of 78) of these isolates were also resistant to tetracycline, erythromycin, chloramphenicol, and trimethoprim . The type 23F isolates were indistinguishable from representative strains of the Spanish 23F clone by these molecular methods, indicating that these strains may be variants of the Spanish 23F clone . Serotype 6B accounted for 19% (20 of 105) of the isolates with reduced penicillin susceptibility and was made up of variants belonging to four different pbp fingerprint groups with the PFGE pattern group B, the predominant group being indistinguishable from that of the Spanish 6B clone . Other PFGE and fingerprint groups were mainly obtained from penicillin-susceptible strains of various serotypes . The results suggest that the rapid emergence of drug-resistant S . pneumoniae in Hong Kong has been due to the rapid dissemination of several successful clones.

Infect Dis Obstet Gynecol, 1999, 7(4), 210 - 3
Intrapartum antibiotic prophylaxis increases the incidence of gram-negative neonatal sepsis; Levine EM et al.; OBJECTIVE: To investigate the influence of the increased use of intrapartum chemoprophylaxis on the incidence of vertically transmitted neonatal sepsis . METHODS: Multiple institutional databases were queried for the number of cases in which intrapartum antibiotics were used, the obstetric risk factors that were present, and the number of resultant cases of neonatal sepsis that occurred for deliveries from 1992 through 1997 . Intrapartum antibiotic use was compared between the first and fourth quarter of 1997 . Comparisons were made between the years 1992-1996 and 1997 for the incidence of the various pathogens causing neonatal sepsis; group B streptococcus (GBS), gram-negative sepsis, and others . RESULTS: We found a significant increase in intrapartum chemoprophylaxis between the first and fourth quarters of 1997 corresponding to the increased physician awareness of published guidelines . As expected, the incidence of neonatal GBS sepsis was drastically reduced (from 1.7/1000 live births to 0 in 3730 births, P = 0.02) . Unfortunately, there was a concomitant increase in the incidence of gram-negative sepsis (0.29/1000 vs . 1.3/1000, P = .02) . The overall incidence of neonatal sepsis remained unchanged (2.7/1000 vs . 2.1/1000, P = .69) . CONCLUSIONS: Published guidelines have encouraged physicians to increase the use of intrapartum chemoprophylaxis to reduce vertical transmission of GBS . This study confirms the efficacy of this approach . Unfortunately, this reduction comes at the cost of increasing the incidence of ampicillin-resistant gram-negative neonatal sepsis with a resultant increased mortality . These data provide compelling evidence that the policy of providing ampicillin chemoprophylaxis in selected patients needs to be reconsidered.

Prev Vet Med, 1999 Jul 20, 41(2-3), 75 - 88
Methods for estimating areas under receiver-operating characteristic curves: illustration with somatic-cell scores in subclinical intramammary infections; Detilleux J et al.; The aim of this study was to demonstrate receiver-operating characteristic (ROC) methodology in the context of bovine intramammary infection (IMI) . Quarter somatic cell scores (SCS) were available to evaluate quarter IMI, and the final IMI diagnosis was made from milk bacteriologic cultures . Data consisted of 11,453 quarter-milk samples collected on 2084 clinically healthy cows located in 154 Belgian herds . Bacteriological analyses showed 16.2%, 7.2%, and 11.9% of quarters infected with coagulase-positive Staphylococcus spp., Streptococcus agalactiae, and coagulase-negative Staphylococcus spp., respectively . The ROC curve indicated all the combinations of sensitivity and specificity that quarter SCS was able to provide as a test to identify quarter IMI . Among parametric, semi-parametric, and non-parametric methods to estimate area under ROC curves, the parametric method seemed the least appropriate for analyzing SCS in this study . With the non-parametric method, the total area under the ROC curves showed quarter SCS could identify quarter IMI with an overall accuracy of 69%, 76%, and 59% for coagulase-positive Staphylococcus spp., S . agalactiae, and coagulase-negative Staphylococcus spp., respectively . Parametric and non-parametric statistical tests showed that overall SCS diagnostic capability was significantly (p<0.01) different from chance and was different (p<0.01) across the three bacteria . However, the SCS thresholds yielding the highest percentage of quarters correctly classified as infected (for the observed prevalence and for equal costs assigned to false-positive and false-negative results) were so high that they had no practical value . The major advantage of ROC analysis is the comprehensive description of the discrimination capacity of SCS for all possible choices of critical values . The major disadvantage is the dependency upon the gold standard used for the final diagnosis--but recent improvements of the methodology will correct the problem.

Arch Ophthalmol, 1999 Aug, 117(8), 1058 - 62
Intravitreal dexamethasone effect on intravitreal vancomycin elimination in endophthalmitis; Park SS et al.; OBJECTIVE: To determine whether intravitreal dexamethasone administration can alter the elimination of intravitreal vancomycin hydrochloride in rabbit eyes with experimental Streptococcus pneumoniae endophthalmitis . METHODS: Albino rabbits were infected with an intravitreal inoculum of S pneumoniae (2 x 10(3) colony-forming units) and randomized after 24 hours to treatment with intravitreal vancomycin hydrochloride (1 mg), alone or in combination with intravitreal dexamethasone (400 microg) . For comparison, uninfected eyes were similarly treated . All eyes were enucleated 24, 48, or 72 hours after treatment, and vitreous levels of vancomycin were quantitated using a fluorescence polarizing immunoassay . RESULTS: The half-life of intravitreal vancomycin in infected eyes was prolonged from 48 to 84 hours when eyes were treated with dexamethasone . Conversely, such treatment shortened the half-life in uninfected eyes from 56 to 42 hours . CONCLUSIONS: Intravitreal dexamethasone administration reduces the elimination of intravitreal vancomycin in rabbit eyes with pneumococcal endophthalmitis, whereas an opposite effect is noted in uninfected eyes . CLINICAL RELEVANCE: In patients with eyes having endophthalmitis caused by virulent organisms, the elimination of intravitreal vancomycin may be reduced when intraocular inflammation is minimized with corticosteroid therapy . This may enhance the efficacy of intravitreal vancomycin therapy in treating the infection.

Immunology, 1999 May, 97(1), 117 - 23
Infection-stimulated infraosseus inflammation and bone destruction is increased in P-/E-selectin knockout mice; Kawashima N et al.; Infections of the dental pulp commonly result in infraosseus inflammation and bone destruction . However, the role of phagocytic leucocytes in the pathogenesis of pulpal infections has been uncertain . In this work we used P/E-/- selectin-deficient mice, which lack rolling adhesion of leucocytes to endothelium and mimic the human syndrome, leucocyte adhesion deficiency II (LAD-II), to test the hypothesis that phagocytic leucocytes protect against pulpal infection and subsequent periapical infraosseus bone resorption . P/E-/- mice and P/E+/+ wild-type controls were subjected to surgical pulp exposure, and both groups were infected with a mixture of pulpal pathogens including Prevotella intermedia, Fusobacterium nucleatum, Peptostreptococcus micros and Streptococcus intermedius . Animals were killed after 20 days, and the extent of infraosseus bone destruction was quantified by histomorphometry . In two separate experiments, P/E-/- mice had significantly greater bone resorption than P/E+/+ controls . The increased bone destruction correlated with a twofold decrease in polymorphonuclear (PMN) infiltration into periapical inflammatory tissues of P/E-/- mice . P/E-/- mice had higher tissue levels of the bone resorptive cytokine, interleukin (IL)-1alpha . Tissue levels of IL-2, IL-4, IL-10, tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were all higher in P/E-/- mice, but the increases were not statistically significant . Only IL-12 was higher in P/E+/+ mice, possibly reflecting a greater number of infiltrating monocytes in wild-type mice . These findings demonstrate that phagocytic leucocytes are protective in this model, and suggest that elevated expression of inflammatory cytokines is responsible for the observed bone destruction.

Mol Microbiol, 1999 Aug, 33(4), 817 - 27
Identification of DNA binding sites for ComE, a key regulator of natural competence in Streptococcus pneumoniae; Ween O et al.; Natural competence in Streptococcus pneumoniae is regulated by a quorum-sensing mechanism consisting of a competence-stimulating peptide (CSP), its dedicated secretion apparatus (ComAB), its histidine kinase receptor (ComD) and a response regulator (ComE) . In this report, we show that ComE is a DNA-binding protein that acts autocatalytically by binding to a region in its own promoter . Two additional ComE binding sites were identified in the pneumococcal genome, one in the promoter region of comAB and the other upstream of an ABC transporter of unknown function . A comparison of the ComE-binding sequences with the sequence motif previously found to be involved in the co-ordinated expression of the late genes revealed that they are unrelated . These findings indicate that ComE activates transcription of the late genes indirectly, i.e . via one or more intermediate factors.

Mol Microbiol, 1999 Aug, 33(4), 778 - 90
Molecular analysis of the role of streptococcal pyrogenic Exotoxin A (SPEA) in invasive soft-tissue infection resulting from Streptococcus pyogenes; Sriskandan S et al.; Epidemiological studies strongly implicate the bacterial superantigen, streptococcal pyrogenic exotoxin A (SPEA), in the pathogenesis of necrotizing soft-tissue infection and toxic shock syndrome resulting from Streptococcus pyogenes . SPEA can act as a superantigen and cellular toxin ex vivo, but its role during invasive streptococcal infection is unclear . We have disrupted the wild-type spea gene in an M1 streptococcal isolate . Supernatants from toxin-negative mutant bacteria demonstrated a 50% reduction in pro-mitogenic activity in HLA DQ-positive murine splenocyte culture, and up to 20% reduction in activity in human PBMC culture . Mutant and wild-type bacteria were then compared in mouse models of bacteraemia and streptococcal muscle infection . Disruption of spea was not associated with attenuation of virulence in either model . Indeed, a paradoxical increase in mutant strain-induced mortality was seen after intravenous infection . Intramuscular infection with the SPEA-negative mutant led to increased bacteraemia at 24 h and a reduction in neutrophils at the site of primary muscle infection . Purified SPEA led to a dose-dependent increase in peritoneal neutrophils 6 h after administration . SPEA is not a critical virulence factor in invasive soft-tissue infection or bacteraemia caused by S . pyogenes, and it could have a protective role in murine immunity to pyogenic infection . The role of this toxin may be different in hosts with augmented superantigen responsiveness.

Mol Microbiol, 1999 Aug, 33(4), 673 - 8
beta-lactam resistance in Streptococcus pneumoniae: penicillin-binding proteins and non-penicillin-binding proteins; Hakenbeck R et al.; The beta-lactams are by far the most widely used and efficacious of all antibiotics . Over the past few decades, however, widespread resistance has evolved among most common pathogens . Streptococcus pneumoniae has become a paradigm for understanding the evolution of resistance mechanisms, the simplest of which, by far, is the production of beta-lactamases . As these enzymes are frequently plasmid encoded, resistance can readily be transmitted between bacteria . Despite the fact that pneumococci are naturally transformable organisms, no beta-lactamase-producing strain has yet been described . A much more complex resistance mechanism has evolved in S . pneumoniae that is mediated by a sophisticated restructuring of the targets of the beta-lactams, the penicillin-binding proteins (PBPs); however, this may not be the whole story . Recently, a third level of resistance mechanisms has been identified in laboratory mutants, wherein non-PBP genes are mutated and resistance development is accompanied by deficiency in genetic transformation . Two such non-PBP genes have been described: a putative glycosyltransferase, CpoA, and a histidine protein kinase, CiaH . We propose that these non-PBP genes are involved in the biosynthesis of cell wall components at a step prior to the biosynthetic functions of PBPs, and that the mutations selected during beta-lactam treatment counteract the effects caused by the inhibition of penicillin-binding proteins.

Intensive Care Med, 1999 Aug, 25(8), 829 - 34
Cervical necrotizing fasciitis: 10 years' experience at a single institution; Mohammedi I et al.; OBJECTIVE: To evaluate clinical and microbiologic characteristics, modalities of treatment and outcome of patients with cervical necrotizing fasciitis admitted to our institution . DESIGN: Retrospective clinical investigation . PATIENTS AND METHODS: We reviewed the charts of 20 consecutive patients hospitalized in our Intensive Care Unit between January 1987 and June 1998 with the diagnosis of cervical necrotizing fasciitis . RESULTS: All the patients required mechanical ventilation . Four of them had mediastinal involvement . The organisms most commonly implicated included Streptococcus, Prevotella, and Peptostreptococcus species . Patients with adequate surgery had a better outcome than those with inadequate surgical procedures . Because no evidence-based recommendations exist in the field of head and neck infections, hyperbaric oxygen was not used as adjunctive therapy . Of the 20 patients, 3 (15 %) died . CONCLUSION: The main finding of this study is that prompt, rather than delayed, surgical debridement correlates with a decrease in morbidity and mortality . However, no definite conclusion is justified due to the relatively small number of patients . Immediate radical debridement, and early redebridement if needed, appropriate antibiotics and intensive care support are critical in controlling these life-threatening infections.

Scand J Infect Dis, 1999, 31(2), 206 - 7
Group A streptococcal brain abscess; Ralph E et al.; A 48-y-old woman with an acute Group A streptococcal brain abscess is described . The abscess enlarged rapidly with neurological deterioration and required open drainage and excision . The patient was treated with antibiotics for 6 weeks and recovered completely . Group A streptococcus is a rare cause of brain abscess in the antibiotic era and may require urgent neurosurgical intervention.

Acta Otolaryngol Suppl, 1999, 540, 67 - 71
The alteration of penicillin-binding proteins (PBPs) in drug-resistant Streptococcus pneumoniae isolated from acute otitis media; Tsurusako Y et al.; Streptococcus pneumoniae is the micro-organism most frequently isolated from acute otitis media (AOM) . Recently, drug-resistant or insensitive strains have been prevalent among pneumococcal AOM cases and were reportedly associated with persistent or recurrent otitis media . The purpose of this study was to examine the alterations of penicillin-binding proteins (PBPs) in Streptococcus pneumoniae isolated from AOM . The PBP samples from 21 clinically isolated strains were examined by 14C-penicillin binding assay and also by adding CCL and CDTR as competitors of 14C-penicillin . Reduced signals in PBP1A and PBP2X/2A were typically observed with the penicillin-resistant Streptococcus pneumoniae samples, while widely different PBP profiles were obtained in each strain of penicillin-insensitive Streptococcus pneumoniae . The competitive binding assay with penicillin-insensitive strains revealed the reduced affinity of CCL to PBPs in comparison with that of CDTR . The results of the penicillin-binding assay were consistent with the results from minimal inhibitory concentration analysis, and its potential usefulness for the prediction of drug resistance was demonstrated.

J Med Assoc Thai, 1999 Jun, 82(6), 587 - 92
Clinical and microbiologic findings in cellulitis in Thai patients; Kulthanan K et al.; BACKGROUND: Cellulitis is an inflammation of subcutaneous tissue in which infective, generally bacterial cause is proven or assumed . However, attempts to culture bacteria from lesions are often unsuccessful . METHOD: One hundred and fifty cases diagnosed as cutaneous cellulitis at Siriraj Hospital between 1992 and 1995 were retrospectively studied . RESULTS: Our study in 150 adult Thai patients with cellulitis showed that the most common site of infection was the lower extremity . Forty two per cent of the patients had history of preceding local trauma . Fever and regional lymphadenopathy were detected in 77.3 per cent and 22.6 per cent respectively . Sixty nine per cent of patients had leukocytosis with a mean neutrophil ratio of 79.7 per cent of patients with underlying diseases predisposed to the infection, 61.6 per cent had positive lesional culture results in contrast to 31.6 per cent in patients without . Needle aspiration and blood gave low positive culture yields . The common organisms detected were S.aureus and Streptococcus group A (83%) in immunocompetent patients . Of immunocompromised patients, in one half of the cases gram negative bacteria were found . CONCLUSIONS: This study showed that in immunocompetent patients, the major bacterial isolated in cellulitis were S.aureus and Streptococcus group A . In immunocompromised patients, gram negative bacteria were found in one half . These findings may help in the selection of antimicrobials before the results of bacterial cultures are available or in culture negative cases.

Eur J Clin Microbiol Infect Dis, 1999 Jun, 18(6), 450 - 3
Comparative activity of 27 antimicrobial compounds against 698 Streptococcus pneumoniae isolates originating from 20 European university hospitals . SENTRY Participants Group; Schmitz FJ et al.; The purpose of this study was to compare the in vitro activity of 27 antimicrobial compounds against 698 clinical Streptococcus pneumoniae isolates collected at 20 European university hospitals . Of the isolates tested, 21.3% were intermediately resistant to penicillin and 6.2% displayed high-level resistance to penicillin . Resistance to different antibiotics was more common among intermediately penicillin-resistant strains than among penicillin-susceptible strains and was most common among high-level penicillin-resistant organisms . The results of the current surveillance study confirm the ongoing trend among European clinical pneumococcal isolates of decreased sensitivity to various antibiotics.

Eur J Clin Microbiol Infect Dis, 1999 Jun, 18(6), 440 - 4
Five-year analysis of antimicrobial susceptibility of the Streptococcus milleri group; Limia A et al.; Susceptibility to 17 antibiotics was studied in 180 strains of the Streptococcus milleri group (88 Streptococcus anginosus, 63 Streptococcus constellatus, and 29 Streptococcus intermedius) isolated over a 5-year period . Minimum inhibitory concentrations of penicillin were in the intermediate range for 5.6% of the strains . Resistance to erythromycin and clindamycin was found in 17.1% and 16.6% of the isolates, respectively . A steady increase in the susceptibility to ciprofloxacin was observed over the study period . Imipenem was the most active beta-lactam agent tested . Glycopeptide antibiotics showed excellent activity . Only slight differences between the three species were found in terms of antibiotic susceptibility . Intermediate resistance to penicillin is appearing among the Streptococcus milleri group in our area; consequently, care must be taken when choosing a macrolide for the management of infections caused by these microorganisms.

J Reprod Med, 1999 Jul, 44(7), 639 - 41
Group A Streptococcus causing PID from an initial pharyngeal infection . A case report; Lamb EK et al.; BACKGROUND: Pelvic inflammatory disease (PID) is a difficult diagnosis . Five billion dollars is spent on over 1 million women diagnosed each year . Atypical organisms and prior history of tubal ligation may complicate the diagnosis . CASE: A woman who had undergone tubal ligation and abstained from intercourse for over two years developed group A streptococcal salpingitis . It occurred following an upper respiratory infection with the same organism . CONCLUSION: PID is rare in a woman with prior tubal ligation who is not engaging in intercourse . In this case it followed an upper respiratory infection with group A Streptococcus . Low diagnostic suspicion must be maintained for uncommon pathogens in PID in women with prior tubal ligation who are not engaging in intercourse.

J Reprod Med, 1999 Jul, 44(7), 587 - 91
DNA probe for beta-hemolytic group B Streptococcus . Diagnostic accuracy in threatened preterm labor; Ryan KM et al.; OBJECTIVE: To determine the diagnostic accuracy of a DNA probe for beta-hemolytic group B Streptococcus (GBS) in women with threatened preterm labor . STUDY DESIGN: Two identical vaginal/perianal samples were collected from 75 pregnant women who were being evaluated for threatened preterm labor . One sample was managed in the traditional manner, with direct plating onto blood agar followed by plating after 8 and 24 hours of LIM broth enhancement . The "gold standard" was 24 hours of LIM broth enhancement followed by blood agar plating . The second sample was placed in LIM broth, and DNA probe testing was performed after incubation for 8 and 24 hours . RESULTS: The prevalence of GBS colonization by the gold standard culture was 32% . After 8 hours of incubation in LIM broth, the DNA probe had poor sensitivity (79%); however, after 24 hours of incubation in LIM broth the DNA probe sensitivity rose to 96% . The DNA probe demonstrated only one false negative result after 24 hours of LIM broth enhancement . All DNA probe results were known 25 hours after sample collection . CONCLUSION: This DNA probe gave results nearly identical to those of standard cultures and allowed a substantial saving of time.

Arzneimittelforschung, 1999 Jul, 49(7), 631 - 4
Activity of aerosol thiamphenicol glycinate acetylcysteinate in a mouse model of S . pyogenes pneumonia; Albini E et al.; Thiamphenicol glycinate acetylcysteinate (TGA, CAS 20192-91-0) is a water soluble ester of thiamphenicol (TAP) that allows a rapid utilization by the systemic route but also a direct local action when used as aerosol . To assess the efficacy of aerosolized TGA in the treatment of experimental pneumonia in mice, we compared its in vivo activity with that of thiamphenicol glycinate hydrochloride (TG), erythromycin (ERT) and amoxicillin (AMX), the last two compounds being more active in vitro than TAP . TGA, administered by aerosol route, showed better efficacy than the aerosolized TG, particularly as far as survival rate is concerned, and was significantly more potent than ERT and similar to AMX either administered by oral route . No significantly different therapeutic efficacy was observed when TGA was parenterally administered . The rapid release, at the site of infection, of TAP and N-acetylcysteine and the favourable pharmacokinetic properties of TGA accounted in large part for its high therapeutic efficacy against Streptococcus pyogenes pneumonia.

J Hosp Infect, 1999 Jul, 42(3), 185 - 92
Hospital-related outbreak of infection with multidrug-resistant Streptococcus pneumoniae in the Netherlands; de Galan BE et al.; Multidrug-resistant strains of Streptococcus pneumoniae were isolated over a two-year period (July 1995 until August 1997) from the sputum of 36 patients who were hospitalized in a Dutch medical centre . Nosocomial transmission was confirmed by typing of the bacterial isolates: all 36 multidrug-resistant isolates shared the same genotype, serotype, and displayed overlapping drug resistance profiles . Thirty-two of the 36 (89%) patients had chronic obstructive pulmonary disease (COPD) . The outbreak was initiated by a 76-year old patient, who had been colonized with the same strain since 1993 . Because staff screening of the hospital and pulmonary function department was negative, patient-to-patient spread was the most likely cause of this outbreak . The epidemic ceased following the commencement of barrier nursing, a treatment course of ceftriaxone, and a five-day rifampicin eradication therapy for the positive patients . The outbreak resulted from failure to recognize quickly the rapid transmission of this multidrug-resistant pneumococcal clone . We conclude that patients with COPD are at high risk of acquiring multidrug resistant pneumococci, and suggest that COPD patients who are colonized or infected with multidrug-resistant pneumococci should be isolated to prevent future transmission.

Drugs, 1999 Jul, 58(1), 1 - 4
Penicillin- and cephalosporin-resistant Streptococcus pneumoniae . Emerging treatment for an emerging problem; Klugman KP et al.; The global emergence of pneumococci resistant to antimicrobial therapy has led to dilemmas in the management of pneumococcal infections . The principles of pharmacodynamics predict that penicillin and cephalosporin therapy of pneumonia will be successful against pneumococci with minimum inhibitory concentrations of penicillin up to 4 micrograms/ml . These predictions are supported by the observations of a number of recent clinical studies . Otitis media therapy is influenced by penicillin-resistance and current recommendations are that amoxicillin is the drug of choice for this infection, given at a double dose of 80 to 90 mg/kg/day . For the therapy of meningitis, cefotaxime or ceftriaxone in maximal doses is recommended and vancomycin may be added if cephalosporin-resistant strains are encountered with reasonable frequency in the population . The new fluoroquinolones with excellent antipneumococcal activity may be considered for use in the setting of pneumonia caused by highly resistant pneumococci and are under evaluation for the management of meningitis.

Enferm Infecc Microbiol Clin, 1999 Jun-Jul, 17(6), 286 - 91
{Prospective study of the invasive strains of Streptococcus pneumoniae isolated in 16 hospitals in Cataluna, Spain}; Latorre C et al.; BACKGROUND: The increasing penicillin resistance rates of Streptococcus pneumoniae led us to review the strains isolated from usually sterile sources during 1996 in 16 hospitals of Cataluna . METHODS: A card was designed for the prospective collection of patients' data . Susceptibility to penicillin, cefotaxime and erytromicin, as well as serotypes, were studied . RESULTS: 237 S . pneumoniae strains were isolated from patients aged from one month to 95 years (19% younger than 5 years), 9.7% of adult patients being HIV antibodies carriers . Global penicillin resistance was of 35.4% (27.4% with minimal inhibitory concentration {MIC} between 0.1 and 1 microgram/ml and and 8.0% > 1 microgram/ml), but it was only of 25% in strains causing meningeal infections, and of 34.1% in those involved in respiratory processes . Paediatric patients less than five years old had a higher resistance rate (47.7%), as well as octagenarian ones (44.7%), but HIV+ patients had a lower rate (30.4%) . 12.2% of strains (10% of meningeal ones) showed some degree of cefotaxime resistance but only five of them (none from meningeal origin) reached a MIC of 2 micrograms/ml . Global erythromicin resistance was 17.7% (17.1% in strains causing respiratory infections) . Prevalent serotypes were 6, 9 and 14 . CONCLUSIONS: The high percentage of strains, mainly from paediatric patients, with diminished penicillin, cefotaxime and erythromicin susceptibility among those causing meningitis and respiratory infections, alerts of possible therapeutic failures if empiric treatments are established in infections produced by this microorganism . For this reason, nowadays it is necessary the routine study of the susceptibility of all pathogen strains of pneumococci . Most strains (208 out of 216) causing invasive disease in our area belong to serotypes covered by the present 23-valent vaccine.

J Bacteriol, 1999 Aug, 181(16), 5004 - 16
Identification of a new regulator in Streptococcus pneumoniae linking quorum sensing to competence for genetic transformation; Lee MS et al.; Competence for genetic transformation in Streptococcus pneumoniae is regulated by a quorum-sensing system encoded by two genetic loci, comCDE and comAB . Additional competence-specific operons, cilA, cilB, cilC, cilD, cilE, cinA-recA, coiA, and cfl, involved in the DNA uptake process and recombination, share an unusual consensus sequence at -10 and -25 in the promoter, which is absent from the promoters of comAB and comCDE . This pattern suggests that a factor regulating transcription of these transformation machinery genes but not involved with comCDE and comAB expression might be an alternative sigma factor . A search for such a global transcriptional regulator was begun by purifying pneumococcal RNA polymerase holoenzyme . In preparations from competent pneumococcal cultures a protein which seemed to be responsible for cilA transcription in vitro was identified . The corresponding gene was identified and found to be present in two copies, designated comX1 and comX2, located adjacent to two of the repeated rRNA operons . Expression of transformation machinery operons, such as cilA, cilD, cilE, and cfl, but not that of the quorum-sensing operons comAB and comCDE, was shown to depend on comX, while comX expression depended on ComE but not on ComX itself . We conclude that the factor is a competence-specific global transcription modulator which links quorum-sensing information transduced to ComE to competence and propose that it acts as an alternate sigma factor . We also report that comAB and comCDE are not sufficient for shutoff of competence-stimulating peptide-induced gene expression nor for the subsequent refractory period, suggesting that these phenomena depend on one or more ComX-dependent genes.

J Infect Dis, 1999 Sep, 180(3), 892 - 5
Synthesis and preclinical evaluation of glycoconjugate vaccines against group B Streptococcus types VI and VIII; Paoletti LC et al.; Group B Streptococcus (GBS) types VI and VIII are prevalent among serotypes isolated from pregnant women in Japan . Maternal vaccination with a safe and effective GBS vaccine has been proposed as a rational approach to prevent neonatal GBS disease . Because antibody specific for the capsular polysaccharide (CPS) antigens of GBS is protective, vaccines were developed with purified type VI and VIII CPS coupled to tetanus toxoid . In rabbits the newly synthesized conjugate vaccines elicited high-titered, type-specific antibody that was opsonically active in vitro . Moreover, litters born to mice actively vaccinated with the conjugate vaccines, in contrast to uncoupled CPS or saline, were protected against an ordinarily lethal challenge of GBS of homologous serotype . GBS types VI and VIII conjugate vaccines of the design presented may be important components of a multivalent GBS vaccine for use in regions where these serotypes predominate.

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