Bacteroides

Cent Afr J Med, 1989 Mar, 35(3), 344 - 51
Vaginal flora of women admitted to hospital with signs of sepsis following normal delivery, cesarean section or abortion . The Puerperal Sepsis Study Group; Mason PR et al.; The microbial flora of the genital tract of 95 women who developed clinical signs of infection within 48 hr of vaginal delivery, Cesarean section delivery or abortion were compared with 111 women who delivered at the same hospital during the same time period but who showed no signs of sepsis . While there were no significant differences in the prevalence of most organisms in the lower genital tract of women with and without sepsis, there was evidence of a higher prevalence of gonococcal, chlamydial and anaerobic infection in the former . Gonococci were isolated from over 20 percent of untreated women with sepsis, more than three times the prevalence in controls . A third of the isolates were penicillinase-producing and another third showed in vitro resistance to penicillin . Chlamydial antigen was detected in 16-20 percent of women with sepsis following vaginal delivery or abortion, compared with 6 percent of controls . Neither gonococcal nor chlamydial infections were significantly associated with sepsis following Cesarean section delivery . Clue cells, indicative of G . vaginalis infection were noted in 20 percent of patients with sepsis compared with 7 percent of controls while amongst the other anaerobes only pigment producing Bacteroides were associated with sepsis . These findings suggest that antepartum investigations for clue cells, chlamydial antigen, gonococci and pigment producing anaerobes may identify patients most at risk from obstetric sepsis in Harare, and identify those for whom prophylactic administration of antibiotics may be of benefit.

Res Vet Sci, 1989 Mar, 46(2), 147 - 52
Environmental influences on the progression of clinical and microbiological parameters of sheep periodontal disease; Frisken KW et al.; The responses of some clinical and microbiological parameters of periodontal disease (PD) in sheep were examined subsequent to transferring animals between PD-affected and PD-free farms . Previously healthy animals showed transient deterioration in some clinical, but not microbiological parameters, which suggests either that a different microbiota to the one studied may be more important in the initiation of the disease, or that sampling did not intercept periods of destructive disease activity in the early lesions . In sheep with established disease, those parameters indicative of periodontitis which included pocket depth and bleeding on probing as well as the proportions of black-pigmented Bacteroides species were not significantly altered by environmental changes . This observation suggests that once the disease is established on PD-affected farms, the hand, some clinical signs of the disease including lengthening and mobility of incisor teeth increased in sheep on the PD-affected farm relative to the PD-free farm . This suggests that the disease may have a complex aetiology.

Diagn Microbiol Infect Dis, 1989 Mar-Apr, 12(2), 165 - 70
Comparison of the bactericidal activity of cefotaxime and desacetylcefotaxime alone and in combination against Bacteroides fragilis group organisms; Aldridge KE et al.; Through the use of time-kill kinetic studies, the bactericidal activity of cefotaxime (CTX) and desacetylcefotaxime (dCTX) alone and in combination against 18 strains of Bacteroides fragilis group was studied . Each isolate was tested at subinhibitory, inhibitory, and suprainhibitory concentrations of each drug as determined from the MIC values . Overall CTX was more bactericidal than dCTX at each of the three concentration levels tested . The combination of CTX and dCTX showed comparable bactericidal activity to CTX at the subinhibitory and inhibitory concentrations, even though each component was present at only one-half the concentration of CTX alone . At suprainhibitory concentrations, the combination of CTX/dCTX appeared synergistic since the combination with each component at a concentration of 1 x MIC was as bactericidal as CTX at a concentration of 4 x MIC . CTX and dCTX alone and in combination exhibited comparable bactericidal activity against test isolates with high (greater than or equal to 32 micrograms/ml) or low (less than or equal to 16 micrograms/ml) MICs . Thus, in vitro the combination of CTX and its naturally occurring metabolite dCTX interacts to produce an additive or synergistic effect against strains of B . fragilis group . Whether the in vitro testing of the combinations is more relevant to clinical outcome than testing CTX alone needs further study.

Plasmid, 1989 Mar, 21(2), 151 - 4
Transferable 5-nitroimidazole resistance in the Bacteroides fragilis group; Breuil J et al.; We report the characterization of a strain of Bacteroides vulgatus, BV17, that exhibits a moderate resistance to 5-nitroimidazoles and carries plasmids of 4.5, 5, 7.7, and 56 kb . A genetic determinant involved in this resistance is carried by the 7.7 +/- 0.2-kb plasmid (pIP417) . This plasmid can be introduced and replicated in a sensitive strain of B . fragilis 638R by transformation or by conjugation . In the latter case, the transfer may involve mobilization by the 56-kb conjugative plasmid (pIP418) regularly found in transconjugants but not in transformants.

Can J Microbiol, 1989 Mar, 35(3), 416 - 22
Development of the cellulolytic microflora in the rumen of lambs transferred into sterile isolators a few days after birth; Fonty G et al.; Seven lambs, separated from their dam 24 h after birth, were kept in a conventional environment until transferred to sterile isolators between 1 and 9 days of age: two on day 1 (IA and IB), two on day 4 (IVA and IVB), one on day 8 (VIIIA), and two on day 9 (IXA and IXB) . The lambs were reared in these isolators until 120 days of age . Lambs IA, IB, IXA, and IXB were free of cellulolytic bacteria when they were placed in the isolators . They were then inoculated with Bacteroides succinogenes S85 which became established in the four lambs . Until the age of 2 months, the population of this strain fluctuated and then stabilized at a high level (10(8)-10(9) cells/mL) . Cellulolytic bacteria were present in the rumen of lambs IVA, IVB, and VIIIA when they were transferred to the isolators . In IVA, and IVB, the cellulolytic population slowly increased with the animal age . In contrast, in VIIIA, the cellulolytic bacteria disappeared within a few days . Bacteroides succinogenes S85 inoculated thereafter became established rapidly and reached a level comparable to that observed in lambs IA and IB . The total number of viable rumen bacteria in the isolated lambs was similar to that observed in conventionally raised animals, but differences were observed in the selective enumeration of bacteria utilizing specific energy sources.

Antimicrob Agents Chemother, 1989 Mar, 33(3), 394 - 5
Comparative in vitro antimicrobial susceptibilities of a special panel of 74 Bacteroides fragilis group isolates in Wilkins-Chalgren agar with and without sheep blood; Gill CJ et al.; Seventy-four cefoxitin-resistant Bacteroides fragilis group isolates were tested by the serial twofold agar dilution method for susceptibility to imipenem and other agents in medium with and without 5% sheep blood . Imipenem (MIC for 90% of strains tested, 1 microgram/ml) and metronidazole (MIC for 90% of strains tested, 2 micrograms/ml) were the two most active agents . The addition of 5% sheep blood to the medium had little or no effect on the activity of the antibiotics tested.

FEMS Microbiol Lett, 1989 Mar, 49(1), 37 - 41
Degradation of intestinal glycoproteins by Bacteroides vulgatus; Ruseler-van Embden JG et al.; Bacteroides vulgatus, isolated from a patient with Crohn's disease, produced in gnotobiotic rats 7 constitutive enzymes that might be concerned with the degradation of intestinal glycoproteins . Furthermore Bacteroides vulgatus caused an almost complete loss of blood group antigenicity of the intestinal glycoproteins . Enzymes with the potency to release toxic compounds from hepatic conjugates and plant glycosides, beta-glucuronidase and beta-glucosidase, respectively, were only detectable in small amounts . These findings indicate that Bacteroides vulgatus, which accounts for 40% of the total flora of patients with Crohn's disease, may play a role in the pathogenesis of Crohn's disease, by increasing the break-down of the mucus layer and therefore damaging its protective function.

Vet Microbiol, 1989 Mar, 19(3), 275 - 81
Bacteroides species from the oral cavity and oral-associated diseases of cats; Love DN et al.; One hundred and sixty-seven strains of Bacteroides were isolated from 71 subcutaneous fight-wound abscesses of cats, 21 cases of feline pyothorax, normal gingival margins from 10 cats and 6 cases of feline gingivitis . Bacteroides species constituted (as a proportion of all anaerobic isolates examined) 44.5% from subcutaneous abscesses, 33.7% from pyothoraxes, 37.5% from normal gingiva and 27.7% from diseased gingiva . Bacteroides tectum comprised 43.7% or 73 of 167 strains, followed by the black- or brown-pigmented asaccharolytic feline species of B . gingivalis, B . salivosus and Group B, comprising 32.3% or 54 of 167 strains . B . heparinolyticus (some 10% or 17 of 167 strains) was the next most common species described . The remainder consisted of two strains of B . fragilis and 21 unspeciated strains . Bacteroides tectum was frequently isolated from subcutaneous abscesses (43.7%) and pyothoraxes (46.6%), and it constituted some 33% of anaerobic isolated from normal gingiva . Bacteroides heparinolyticus was more commonly encountered in purulent lesions (abscesses and pyothoraxes) than in the oral cavity.

Nippon Shishubyo Gakkai Kaishi, 1989 Mar, 31(1), 43 - 54
{Correlation between subgingival microflora and peptidase activity in periodontal pockets measured with synthetic substrates}; Miyazawa Y; The activity of peptidases in periodontal pockets of patients were examined by using four different synthetic enzyme substrates, and surveyed their correlation with the microbial populations of subgingival plaque and clinical symptoms . The substrates were (1) alpha-N-benzoyl-DL-arginine-beta-naphthylamide (BANA), (2) N-carbobenzoxy-glycylglycyl-arginine-4-methoxy-beta-naphthylamide, (3) alpha-N-benzoyl-L-arginylglycyl-L-phenylalanyl-L-proline-4-methoxy -beta-naphthylamide and (4) N-carbobenzoxy-prolyl-L-alanylglycyl-L-proline-4-methoxy-beta naphthylamide . Whereas substrates (1) and (2) were hydrolyzed more specifically by peptidases of mainly Bacteroides gingivalis and Treponema denticola, substrates (3) and (4) were susceptible to most of the strains of black-pigmented Bacteroides, Capnocytophaga and T . denticola . Correlation between the peptidase activity and the level of Spirochetes in the plaques were observed with the substrates (1), (2) and (3) . Substrate (3) had the strongest correlation also with the level of the black-pigmented Bacteroides and with the depth of the periodontal pockets, suggesting that it is a better substrate for enzymatic diagnosis than BANA which is currently used as an indicator of oral Spirochetes and the black-pigmented Bacteroides.

Nippon Shishubyo Gakkai Kaishi, 1989 Mar, 31(1), 29 - 42
{Microbial flora of periodontitis and monitoring of the effect of initial preparation by immunofluorescence microscopy}; Seida K; The effect of initial preparation in adult periodontitis was evaluated by changes in clinical parameters and immunofluorescence microscopic counts of periodontal disease associated bacteria . Subgingival plaque samples were taken with sterilized paper points from 10 sites of 5 periodontally healthy persons and 44 sites of 23 adult periodontitis patients . Twenty-one diseased sites were periodically examined after plaque control and scaling, root planing . The direct immunofluorescence technique was used to detect Bacteroides gingivalis, Eikenella corrodens, Fusobacterium nucleatum and Treponema denticola, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Bacteroides forsythus and Wolinella recta were counted by the indirect immunofluorescence technique . The proportions of B . gingivalis, B . forsythus, F . nucleatum, E . corrodens, T . denticola and W . recta in periodontitis lesions were significantly higher than those in healthy sites . The proportions of B . gingivalis and T . denticola were significantly related to GI, PlI, BI and PD, those of B . forsythus and W . recta to GI, PlI and BI, E . corrodens to GI and PlI, and F . nucleatum to BI . Reduced proportions of T . denticola were found in samples taken after establishment of proper plaque control . Subgingival scaling and root planing resulted in the reduction of proportions of B . gingivalis, E . corrodens, T . denticola and B . forsythus in the samples . The samples from positive bleeding sites contained higher proportions of B . gingivalis, T . denticola, B . forsythus and W . recta than did resolved sites . The present study shows that the immunofluorescence technique which detects B . gingivalis, T . denticola and B . forsythus is useful in monitoring the efficacy of initial preparation.

Nippon Shishubyo Gakkai Kaishi, 1989 Mar, 31(1), 13 - 28
{Microbiological evaluation of initial preparation for adult periodontitis patients}; Nakagawa T; The microbial flora from 46 adult periodontitis lesions of 23 patients and 18 sites in 9 healthy persons were examined and levels of serum IgG antibody to gram negative periodontal disease-associated bacteria were measured by enzyme-linked immunosorbent assay . Plaque samples and serum samples were taken 40-50 days after initial preparation consisting of scaling and root planing . To evaluate the effects of the therapy on 10 patients with adult periodontitis, changes in clinical parameters were compared with alterations of the microbial flora and serum IgG antibody levels . Black-pigmented Bacteroides species, mainly Bacteroides gingivalis, were found to be predominant in periodontitis lesions . A significant relationship was found between the prevalence of B . gingivalis and elevated titers of serum IgG antibody against the microorganism . No relationships between Bacteroides intermedius, Actinobacillus actinomycetemcomitans and elevated titers of serum IgG antibody to them were detected . The fact that there was no marked reduction of serum IgG antibody to B . gingivalis after initial preparation suggests that a more extended, longitudinal study is required . Although brushing resulted in a significant reduction of the number of total cultivable organisms in samples from periodontal pockets, no significant proportional changes in gram-negative bacteria in the lesional flora were found . Initial preparation was not effective in eliminating gram-negative bacteria from deep periodontal pockets . However, the microbiological shifts, especially the reduction in the proportion and frequency of detection of B . gingivalis in periodontal pockets, was paralleled by significant improvement in the clinical parameters.

J Antimicrob Chemother, 1989 Mar, 23(3), 383 - 8
Effect of Bacteroides fragilis on mortality induced by Escherichia coli in an experimental infection treated with cefotaxime, aztreonam or gentamicin; Soriano F et al.; The possibility that beta-lactamase-producing strains of Bacteroides fragilis can protect Escherichia coli from cefotaxime was studied in an in-vivo model of peritoneal infection in rats . The protective effect of cefotaxime, aztreonam and gentamicin in peritonitis induced by E . coli alone or combined with B . fragilis was evaluated by analysing mortality at 24 and 48 h after bacterial inoculation and treating the animals with two doses of each antibiotic . Comparisons, by drugs, at 24 and 48 h revealed that a statistically significant high mortality rate was obtained at 48 h when mixed infections were treated with cefotaxime, a drug very active in the infection caused by E . coli alone . Infections by mixed flora or E . coli alone treated with aztreonam or gentamicin did not show any significant difference in mortality rate analysed at 24 or 48 h . These in-vivo results confirm previous in-vitro studies and suggest that cefotaxime could be inactivated in mixed infections if a beta-lactamase-producing strain, such as B . fragilis, is involved in a clinical infection.

Zentralbl Bakteriol Mikrobiol Hyg {A}, 1989 Mar, 270(4), 492 - 502
Rapid diagnosis of intestinal Bacteroides species by means of the immunofluorescence; Hohne C et al.; Rapid methods serving the detection of intestinal Bacteroides species in clinical specimens are of great significance . For this purpose, an identification of the species is possible at present only by means of immunofluorescence (IF) . Using preparations of antigens of different intestinal Bacteroides species (B . fragilis, B . thetaiotaomicron, B . uniformis, B . ovatus, and B . distasonis) as well as immune sera prepared against them, the presented results have shown the possibility of specific identification of the species involved by means of direct and indirect IF, respectively . However, it could be demonstrated that the direct IF results in a more brilliant appearance of the bacteria than the indirect procedure . Convincing results could be obtained also in the investigation of clinical specimens by means of the direct IF using a pool of conjugated immunoglobulin fractions (sensitivity 88%, specificity 100%) . Therefore, the direct method to detect intestinal Bacteroides species by IF should be preferred.

J Bacteriol, 1989 Mar, 171(3), 1294 - 302
Cloning and characterization of a Bacteroides conjugal tetracycline-erythromycin resistance element by using a shuttle cosmid vector; Shoemaker NB et al.; The Bacteroides conjugal tetracycline resistance (Tcr) elements appear not to be plasmids . In many cases, resistance to erythromycin (Emr) is cotransferred with Tcr . Using a newly constructed shuttle cosmid, pNJR1, we cloned 44 to 50 kilobase pairs of a conjugal Tcr Emr element on overlapping cosmid clones . Cosmid libraries were made in Escherichia coli with DNA from the original clinical Bacteroides thetaiotaomicron DOT strain containing Tcr Emr-DOT or from a Bacteroides uniformis Tcr Emr-DOT transconjugant strain . The cosmid clones were mobilized from E . coli into B . uniformis in groups of 10 to 20 per filter mating, with selection for Tcr or Emr transconjugants . The Tcr and Emr genes were cloned both separately and together on 30-kilobase-pair fragments . Several of the Tcr clones also contained transfer genes that permitted self-transfer of the cosmid from B . uniformis donors to E . coli or B . uniformis recipients . Neither the Tcr nor the Emr gene conferred resistance on E . coli, and the transfer-proficient clones did not self-transfer out of E . coli . Southern blot analysis was used to compare DNA from independently isolated Bacteroides strains carrying conjugal Tcr or Tcr Emr elements and their respective B . uniformis transconjugants . Results of these analyses indicate that there are large regions of homology, including regions outside the Tcr and Emr genes, but that the elements are not identical . Some Tcr clones contained a region which hybridized to chromosomal DNA from the wild-type B . uniformis recipient strain that did not carry the Tcr Emr-DOT element . This region of homology appeared not to be a junction fragment . It was not required in a Bacteroides recipient for successful transfer of the Tcr Emr element . Although we are not sure we have cloned a junction fragment between the Tcr Emr-DOT element and the B . uniformis chromosome, the preliminary function and restriction map appears to be linear.

Nippon Shishubyo Gakkai Kaishi, 1989 Mar, 31(1), 156 - 65
{Effects of periodontopathic bacterial components on phagocytic activity of rat peritoneal macrophages . Examination using ELISA}; Ichimura K et al.; This study examined the phagocytic activity of rat peritoneal resident macrophages to determine the movement of macrophages in local inflammation in periodontal disease . We studied phagocytic activity by enzymelinked immunosorbent assay (ELISA) and used the peroxidase-anti-peroxidase soluble complex (PAP; soluble immune complex) as a marker in . We also determined the basic conditions of this examination and studied the effects of bacterial components and the supernatants of sonicated periodontopathic bacterias . We obtained the number of applied macrophages, the concentration of PAP to use and the incubation time . The phagocytic activity of macrophages was enhanced significantly by the bacterial components lipopolysaccharide (LPS) and muramyldipeptide (MDP) . Phagocytic activity was also enhanced by the addition of the supernatant of sonicated Bacteroides gingivalis at 40 micrograms/ml (concentration of protein) and significantly suppressed at 320 micrograms/ml . Moreover, activity was significantly enhanced by the supernatant of sonicated Capnocytophaga suputigena at 40 micrograms/ml and 160 micrograms/ml, and suppressed by the supernatant of Fusobacterium nucleatum at a low concentration of protein (5 micrograms/ml) . These results suggested that LPS of gram-negative bacteria's endotoxicity and MDP on pivotal structure of peptidoglycans, which are bacterial cell surface components, exerted an effect on phagocytic activity . It was further indicated that the phagocytic activity of macrophages varied with the effects of each periodontopathic bacteria.

Nippon Shishubyo Gakkai Kaishi, 1989 Mar, 31(1), 1 - 12
{Effects of anti-Bacteroides gingivalis (Bg), and anti-Actinobacillus actinomycetemcomitans (Aa) antibodies on Bg and Aa}; Horino K et al.; The purpose of this study was to determine the effects of anti-Bacteroides gingivalis (Bg) and anti-Actinobacillus actinomycetemcomitans (Aa) antibodies on Bg and Aa respectively . Bg and Aa were resistant to complement-mediated bactericidal activity, and killing by PMN . However a significant reduction in CFU of Bg and Aa was found when these bacteria were incubated with the antibodies and not agitated . This would suggest that the antibody was capable of aggregating or phagocytizing, but not killing, these bacteria when complement and PMN were added . Moreover the antibodies had no effect on bacterial proliferation . Anti Aa antibody also had no effects on killing of Aa or PMN infiltration in experimentally established periodontal pockets in dogs.

Oral Microbiol Immunol, 1989 Mar, 4(1), 6 - 11
Experimental infections by Bacteroides gingivalis in non-immunized and immunized rabbits; Dahlen G et al.; The interactions between Bacteroides gingivalis and systemic antibodies were studied in tissue cages implanted in the backs of New Zealand white rabbits . Infectivity was evaluated according to clinical signs and to leukocyte and bacterial counts in material aspirated from the tissue cages . Pre- and post-inoculation antibody levels to sonicated whole bacterial cells were determined by enzyme-linked immunosorbent and agar immunodiffusion assays . Rabbits immunized against B . gingivalis and then challenged with pure cultures of B . gingivalis revealed complete elimination or markedly lower postinoculation bacterial counts and considerably weaker tissue reactions than non-immunized animals . B . gingivalis co-inoculated with Actinobacillus actinomycetemcomitans caused significantly more severe infections than observed in monoinfected animals . The present results suggest that the immune system acting through systemic antibodies and/or cellular mechanisms may modulate the pathogenic potential of infecting periodontal pathogens.

Oral Microbiol Immunol, 1989 Mar, 4(1), 24 - 9
Immunomodulatory effects of Bacteroides products on in vitro human lymphocyte functions; Shenker BJ et al.; Bacteroides spp . have been implicated in the pathogenesis of several diseases, including periodontal diseases . In this study sonic extracts of 6 Bacteroides spp . were examined for their abilities to alter human lymphocyte function . We found that soluble extracts from Bacteroides intermedius, Bacteroides endodontalis, Bacteroides asaccharolyticus, Bacteroides melaninogenicus, and to a lesser degree Bacteroides loescheii, caused dose-dependent inhibition of human lymphocyte responsiveness to both mitogens and antigens . Suppression involved altered DNA, RNA and protein synthesis as well as immunoglobulin production . In contrast, Bacteroides gingivalis did not suppress these responses; instead, it stimulated lymphocyte proliferation and enhanced immunoglobulin production . It has been proposed that impaired host defense may play a pivotal role in the pathogenesis of many infections . The data presented in this paper suggest that microbial mediated immunosuppression may conceivably alter the nature and consequences of host-parasite interactions in periodontal disease.

Oral Microbiol Immunol, 1989 Mar, 4(1), 19 - 23
Studies on the virulence properties and metabolism of pleiotropic mutants of Porphyromonas gingivalis (Bacteroides gingivalis) W50; Shah HN et al.; Porphyromonas gingivalis (Bacteroides gingivalis) strain W50 and variants isolated from continuous culture designated W50/BP1 (black pigmented), W50/BR1 (brown pigmented) and W50/BE1 (beige or non-pigmented) were previously shown to lose virulence with the loss of pigmentation . Major properties which may affect the virulence and metabolism of P . gingivalis were compared amongst the 4 strains . The non-pigmented strain lost the ability to hemagglutinate sheep erythrocyte, had a reduced hydrophobicity and possessed lower levels of proteolytic activity . Defects in the electron transport system occurred at the level of cytochrome b but not menaquinone synthesis and resulted in an altered metabolic end product profile of the non-pigmented strain.

Oral Microbiol Immunol, 1989 Mar, 4(1), 12 - 8
Further studies on the degradation of immunoglobulins by black-pigmented Bacteroides; Grenier D et al.; The ability of several species of black-pigmented Bacteroides to degrade immunoglobulins A and G was confirmed in this study . The cleavage products from IgG strongly stimulated the growth of bacteria degrading IgG . Growth of Bacteroides gingivalis on limiting media supplemented with IgG paralleled growth on complete medium . The degradation of IgG and IgA by black-pigmented Bacteroides appeared to occur in 2 stages . The molecules were broken into large fragments which were subsequently degraded into small peptides not visible on SDS-PAGE . B . gingivalis degraded IgG to peptides with Mrs of 33,000 and 11,000 whereas Bacteroides asaccharolyticus, Bacteroides intermedius and Bacteroides loescheii formed only the 33,000 Mr peptide . Electrophoresis in polyacrylamide gels containing covalently linked IgG, IgA and bovine serum albumin revealed that B . gingivalis elaborated 8 electrophoretically distinct proteolytic activities . The proteases protected the cell from reaction with anti-B . gingivalis antibody and were capable of hydrolyzing antibody bound to the bacterial cell surface.

J Gen Microbiol, 1989 Mar, 135 ( Pt 3), 557 - 64
Production of cell-bound and vesicle-associated trypsin-like protease, alkaline phosphatase and N-acetyl-beta-glucosaminidase by Bacteroides gingivalis strain W50; Minhas T et al.; Bacteroides gingivalis strain W50 was grown in batch and continuous culture on complex medium with haemin . In batch culture, cell-bound levels of trypsin-like protease (EC 3.4.21.4), alkaline phosphatase (EC 3.1.3.1) and N-acetyl-beta-glucosaminidase (EC 3.2.1.30) increased during the exponential phase of growth . These enzyme activities were also detected in extracellular vesicles and in extracellular soluble forms in the supernatant fluid, but in lower amounts per unit biomass compared to cell-bound levels . In continuous culture, at high relative growth rates (0.7-0.9 murel), the highest proportions of enzyme activities were cell-bound . In contrast, at low relative growth rates (0.1-0.2 murel), highest enzyme levels were detected in the extracellular vesicle fraction . Levels of extracellular soluble enzymes were always low compared to cell-bound or extracellular vesicle levels, but were highest at low relative growth rates . All three enzymes appeared to be relatively stable in their soluble forms . Vesicle production appeared to be associated with actively growing cells but was influenced by growth rate . The results are consistent with the hypothesis that cell-bound 'periplasmic' enzymes are encapsulated into vesicles which are subsequently released by the cells . Therefore, levels of total extracellular enzyme (extracellular vesicle plus extracellular soluble) may depend on the rate of vesicle formation superimposed on the rates of production of 'periplasmic' enzymes in the cell.

J Periodontal Res, 1989 Mar, 24(2), 96 - 105
Microbiota and crevicular fluid collagenase activity in the osseointegrated dental implant sulcus: a comparison of sites in edentulous and partially edentulous patients; Apse P et al.; The soft tissues adjacent to osseointegrated dental implants (OII) were investigated using clinical, biochemical and microbiological methods . Tooth and implant crevices were compared in 15 partially edentulous patients, examining 28 peri-implant and 19 periodontal sites, and in 6 edentulous patients, examining 13 implant sites . Sites were classified by standard periodontal indices; the crevicular fluid flow determined; crevicular fluid was collected for collagenase assays; and the subgingival bacterial flora was examined and cultured . Differences in clinical parameters were noted in that implants had significantly less keratinized gingiva and deeper probing depths . Crevicular fluid was present in the OII sulcus but the crevicular fluid flow did not differ from that observed from tooth sites either in the partially edentulous or edentulous patients . Tissue collagenase activity and collagenase inhibitor were detected in the implant crevicular fluid and, as in periodontal sites, a strong inverse relationship was found between the levels of active collagenase and collagenase inhibitor . Microbiology included darkfield microscopy, anaerobic culturing for total colony forming unit counts and identification of black pigmented Bacteroides (BPB) . Few differences were observed between implants and teeth in partially edentulous patients, indicating that crevices around teeth may act as reservoirs of bacteria which can colonize implant sites . A higher percentage of BPBs and wet spreaders (Capnocytophaga) was noted at partially edentulous implant sites when compared with edentulous implant sites, perhaps reflecting the lower numbers of periodontal pathogens present in edentulous mouths . Overall, the characteristics of implant sulci appear to be similar to periodontal sulci with respect to crevicular fluid flow and microflora.

Infect Immun, 1989 Mar, 57(3), 745 - 53
A soluble Bacteroides by-product impairs phagocytic killing of Escherichia coli by neutrophils; Rotstein OD et al.; The effect of Bacteroides culture filtrate on killing of Escherichia coli by neutrophils was examined as a potential mechanism for E . coli-Bacteroides microbial synergy . A low-molecular-weight heat-stable factor present in the 22-h culture filtrate of Bacteroides fragilis 9032 impaired neutrophil killing function . To determine whether short-chain fatty acids present in the filtrate could account for the inhibition, the fatty acid content of the culture filtrate was determined and sterile medium supplemented with measured concentrations of fatty acids was tested for its effect on neutrophil function . Succinic and acetic acids were measured in high concentrations, while lactic, formic, and fumaric acids were present in lower concentrations . Reconstituted media mimicked the inhibitory effect of B . fragilis filtrate on neutrophil killing capacity . In further support of the hypothesis that short-chain fatty acids were responsible for the inhibition, the filtrates of other Bacteroides strains were found to be inhibitory only after bacterial growth had entered the stationary phase, a period during which fatty acid production is maximized . Further studies investigating the mechanism of impaired neutrophil killing showed that B . fragilis 9032 culture filtrate inhibited both phagocytosis of {3H}thymidine-labeled E . coli by neutrophils and the intrinsic microbicidal functions of the neutrophil . Impairment of neutrophil superoxide production was mediated via the ability of short-chain fatty acids present in B . fragilis filtrate to reduce neutrophil cytoplasmic pH . These studies suggest that Bacteroides strains capable of reaching stationary phase in vivo may contribute to the pathogenesis of mixed infections by direct inhibition of neutrophil function.

J Periodontal Res, 1989 Mar, 24(2), 155 - 60
Bactericidal concentrations of chlorhexidine-digluconate, amine fluoride gel and stannous fluoride gel for subgingival bacteria tested in serum at short contact times; Oosterwaal PJ et al.; In vitro inhibitory and bactericidal concentrations in serum of chlorhexidine-digluconate, amine fluoride gel, stannous fluoride gel, stannous fluoride, metronidazole and amoxicillin were determined against Bacteroides gingivalis, Bacteroides intermedius, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans and Capnocytophaga sputigena . The minimal inhibitory concentration was assessed by the agar dilution technique . The killing curves and minimal bactericidal concentration of the antimicrobial agents in inactivated bovine serum were determined after 5, 10, 20 and 60 minutes contact time . The minimal inhibitory concentration varied amongst the tested bacteria . A concentration of 128 micrograms/ml chlorhexidine digluconate, 20 mg/ml amine fluoride gel, 1 mg/ml stannous fluoride, 128 micrograms/ml metronidazole and 4 micrograms/ml amoxicillin inhibited the growth of the tested species . The minimal bactericidal concentration in serum for B . gingivalis, B . intermedius, F . nucleatum, A . actinomycetemcomitans and C . sputigena after 10 min contact time was 5 mg/ml for chlorhexidine digluconate and 100 mg/ml for amine fluoride gel . A concentration of 200 mg/ml stannous fluoride gel in serum was bactericidal for the tested species after 10 min contact time, with exception of F . nucleatum.

J Periodontal Res, 1989 Mar, 24(2), 113 - 20
Prevalence of Bacteroides forsythus and Bacteroides gingivalis in subgingival plaque of prosthodontically treated patients on short recall; Gmur R et al.; The prevalence of Bacteroides forsythus and Bacteroides gingivalis in subgingival plaque of patients on short recall was analyzed in relation to the probing depth of the test sites . The subjects had excellent oral hygiene and therefore were unlikely to suffer from active periodontal destruction . Sixty-four subgingival plaque samples, taken from gingival or periodontal pockets with probing depths ranging from 1 to 8 mm, were quantitatively assessed for the presence of the two species using species-specific monoclonal antibodies in conjunction with a very sensitive indirect immunofluorescence technique . Both organisms were encountered in probes from sites as shallow as 2 mm, but the percentage of positive samples clearly rose in relation to the probing depth of the test sites . Overall, B . forsythus was found to colonize lesions earlier, that is at smaller probing depths, than B . gingivalis . Interestingly, whenever a sample was found to be positive for B . gingivalis it was also positive for B . forsythus . The numbers of B . forsythus and B . gingivalis and the total bacterial cell number found in the pockets were significantly correlated to the probing depth . However, with advancing probing depth the increase of the total cell numbers of the two Bacteroides species was considerably more pronounced than the increase of the total subgingival plaque cell number . The recall interval neither affected the frequency of sites positive for B . forsythus or B . gingivalis nor influenced significantly the proportions of the two species in subgingival plaque.(ABSTRACT TRUNCATED AT 250 WORDS)

Clin Exp Immunol, 1989 Feb, 75(2), 245 - 51
Limit dilution analysis of peripheral blood T lymphocytes specific to periodontopathic bacteria; Mahanonda R et al.; Limit dilution analysis (LDA) was used to determine the presence and frequency of periodontopathic-bacteria-specific T cells in the peripheral blood of patients with chronic inflammatory periodontal disease . Twelve adult periodontitis (AP), 13 marginal gingivitis (MG) and 12 healthy control subjects took part in the study . Bacteroides gingivalis and Actinomyces viscosus were used as test organisms, while tetanus toxoid was used as the control antigen . The median PTL-p frequencies to B . gingivalis were 46.33 x 10(-6), 45.33 x 10(-6) and 58.83 x 10(-6) in the control, gingivitis and AP groups respectively, while the median PTL-p frequencies to A . viscosus were 13.8 x 10(-6), 17.33 x 10(-6) and 11.5 x 10(-6), again in the control, gingivitis and AP groups . There were no statistically significant differences between the groups . All subjects displayed 'single-hit' kinetics with the control tetanus toxoid antigen and, with three exceptions, 'single-hit' kinetics was also found with the two test organisms . One control subject displayed a 'saw-tooth' curve with A . viscosus and a 'suppressor' curve with B . gingivalis, while two MG subjects had a 'saw-tooth' curve with B . gingivalis . These complex curves suggest that, in some subjects, more than one limiting cell type may exist in the cultures . Nevertheless, the results of the present study illustrate that lymphocytes specific to periodontopathic bacteria exist in the peripheral blood of both diseased and non-diseased subjects.

Can J Microbiol, 1989 Feb, 35(2), 313 - 7
Effects of methanol on the growth of gastrointestinal anaerobes; Caldwell DR; The effects of methanol on the growth of representative, predominant, anaerobic gut bacteria were studied . Growth yields and rates were determined in a base medium to which methanol was added to produce media with methanol concentrations varying, in twofold steps, over a concentration range of 0.01 to 25%, by volume . The growth of many of the organisms was completely inhibited by a methanol concentration equal to, or less than, 6.2% . Isolates representing cellulolytic species were completely inhibited at a methanol concentration of 3.1%, and inhibitory effects on the yield of some cellulolytic isolates were found at a methanol concentration as small as 0.01% . Although most of the organisms studied were inhibited at relatively small methanol concentrations, isolates of Selenomonas ruminantium, Bacteroides ovatus, and Fusobacterium necrophorum were relatively methanol resistant . A methanol concentration of 12.5% was required to completely inhibit S . ruminantium . Substantial growth of B . ovatus was obtained in media containing 12.5% methanol, and for F . necrophorum, substantial growth occurred in media containing 25% methanol . The yields of F . necrophorum strain B85 and S . ruminantium strain PC18 were enhanced by relatively small methanol concentrations and reduced with further methanol concentration increase Anaerobic, nonsporing gut bacteria exhibit a diversity of responses to methanol.

Antimicrob Agents Chemother, 1989 Feb, 33(2), 242 - 4
Macrolide accumulation by Bacteroides fragilis ATCC 25285; Muto Y et al.; The accumulation of macrolide antibiotics in Bacteroides fragilis ATCC 25285 was increased in the order erythromycin, josamycin, and rokitamycin, depending on hydrophobicity . The half-times of efflux were also prolonged in the same order . Furthermore, MICs of the antibiotics were correlated with the extent of hydrophobicity . These findings suggest that the macrolide antibiotics are accumulated in B . fragilis by means of their hydrophobic properties, and the efficient accumulation of the drugs may explain the susceptibility of this gram-negative bacterium to macrolides.

Zh Mikrobiol Epidemiol Immunobiol, 1989 Feb, (2), 20 - 4
{A study of the features of E . coli bacteroid infection in experiments on mice}; Komarovskaia TP et al.; Experiments on the intraperitoneal infection of F1 (CBA X C57BL/6) mice with bacteroids of the group Fragilis in combination with E . coli have revealed the presence of a synergic effect leading to more pronounced (greater frequency of abscess formation) and even qualitatively new (necrotic lesions of the liver) pathological changes in comparison with those observed in monoinfections . Bacteroides fragilis strain 1/1087 gamma has been shown to have greater virulence than that of Bacteroides vulgaris strain 18; their virulence was determined from the capacity of microorganisms for survival in the abdominal cavity of mice, as well as from their capacity for inducing the formation of necrotic lesions and abscesses.

J Periodontol, 1989 Feb, 60(2), 96 - 103
Antibodies to Bacteroides gingivalis in patients with treated and untreated periodontal disease; Murray PA et al.; It is proposed that the development of periodontal disease is associated with rising levels of serum and gingival crevice fluid (GCF) IgG antibodies to specific organisms, while treatment of periodontal disease is associated with a decline in specific IgG antibodies . This study examined the immune response to Bacteroides gingivalis, a suspected periodontal pathogen, in serum and GCF of patients with adult periodontitis . Three groups of subjects were studied: (1) patients with untreated adult periodontitis, (2) patients with treated adult periodontitis, and (3) patients with gingivitis (controls) . An enzyme-linked immunosorbent assay was employed using whole formalinized B . gingivalis (ATCC 33277) as antigen . Results showed that the untreated adult periodontitis patients had a humoral immune response to B . gingivalis, producing significantly higher serum levels of IgG antibody to that organism than did patients with treated adult periodontitis (p less than or equal to 0.01) or gingivitis (p less than or equal to 0.005) . The untreated patients also demonstrated a local immune response to B . gingivalis in that their GCF levels of IgG antibody to that organism were also significantly higher than levels in treated adult periodontitis patients (p less than or equal to 0.005) and gingivitis patients (p less than or equal to 0.001) . These results are consistent with reports by other investigators . However, ratios of GCF antibody to serum antibody in the untreated adult periodontitis group were not significantly higher than ratios in the other two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Immun, 1989 Feb, 57(2), 338 - 43
Induction of macrophage procoagulant activity by Bacteroides fragilis; Rosenthal GA et al.; Fibrin deposition in the peritoneal cavity during acute peritonitis appears to predispose the host to abscess formation by providing an environment for bacterial proliferation protected from host defenses . The purpose of the present study was to determine whether the potent abscess-inducing anaerobe Bacteroides fragilis could promote fibrin deposition by inducing mononuclear cells to express procoagulant activity (PCA) . B . fragilis stimulated PCA in a dose-dependent fashion, achieving a maximum at 10(7) CFU/ml . Heat-killed B . fragilis induced comparable levels of PCA, while a nonspecific phagocytic stimulus, latex beads, was not stimulatory . B . fragilis was capable of inducing PCA even when phagocytosis was blocked by preexposure of cells to latex beads . The results suggested that phagocytosis was neither necessary nor sufficient for the generation of PCA . Cell separation studies showed that PCA was solely produced by macrophages and that lymphocytes did not augment its production . These studies suggest one potential mechanism by which B . fragilis might initiate abscess formation.

Surg Gynecol Obstet, 1989 Feb, 168(2), 112 - 4
No effect of topical ampicillin prophylaxis in elective operations of the colon or rectum; Raahave D et al.; Whether or not topical application of ampicillin is necessary in patients undergoing elective colorectal operations was investigated . After mechanical preparation, 193 patients received 2 grams of cefotaxime administered intravenously from the start of the operation; patients received two more doses within the next 12 hours . In addition, patients were randomized to receive or not receive prophylaxis against infection of 2 grams of ampicillin in the site of the incision at closure . Twenty-three patients did not complete the study . Wound infection occurred in five of 81 patients who had topical application of ampicillin compared with six of 89 patients who did not receive prophylaxis; the difference was not significant . There were no significant differences in rates of wound dehiscence, intra-abdominal abscess or anastomotic leakage . Escherichia coli and Bacteroides fragilis were the predominant microorganisms isolated . Thus, topical application of ampicillin did not lower the wound infection rate when there was a preoperative antibiotic administered intravenously.

Endod Dent Traumatol, 1989 Feb, 5(1), 1 - 10
Bacteroides spp . in dental root canal infections; Haapasalo M; A summary of a series of bacteriological studies of endodontic infections is presented in this article . The bacteriology of 62 root canal infections was studied with special attention focused on the occurrence, role and taxonomy of Bacteroides spp . All infections except one were mixed infections dominated usually by anaerobic bacteria . Four to 6 different species were present in most canals . Species of the genus Bacteroides were found more frequently than species of any other genus . Seventy-eight Bacteroides strains were isolated from 45 canals . B . buccae, B . intermedius, B . denticola, B . oris, B . oralis, and B . gingivalis were the most common Bacteroides spp . At the beginning of the treatment 35 of 62 teeth caused acute symptoms . The results indicated that symptoms were a result of the synergistic action of the mixed anaerobic flora . The presence of B . gingivalis, B . endodontalis, and B . buccae was more often related to acute cases than other Bacteroides spp . Black-pigmented Bacteroides and a new Bacteroides-like organism, Mitsuokella dentalis, seemed to increase the probability that acute symptoms would persist one week after the beginning of the treatment . However, the treatment result assessed after 4 weeks and after 1 year was not affected by the composition of the mixed anaerobic flora . Calcium hydroxide was the only canal disinfectant used . Its efficacy was proved by a bacteriological sample at the second appointment in 10 cases . All teeth were asymptomatic at the third appointment . The susceptibility of the isolated Bacteroides strains to penicillin G was also studied . Only 2 B . buccae strains and 2 B . denticola strains were resistant at a concentration of 2.4 micrograms/ml . The patients were randomly divided into 3 groups which received 1) no antibiotics, 2) penicillin V (650 mg x 3) for 7 days, or 3) for 12 weeks . There was no difference between the 3 groups in the healing of the periapical lesion after one year . All patients attended the 1-year control . Fifty cases showed complete healing, partial healing was obtained in 11 cases and in 1 case no healing was observed.

Infect Immun, 1989 Feb, 57(2), 566 - 73
Immunochemical identification and preliminary characterization of a nonfimbrial hemagglutinating adhesin of Bacteroides gingivalis; Mouton C et al.; A cell-bound hemagglutinating adhesin (HA-Ag2) of Bacteroides gingivalis was identified by crossed immunoaffinity electrophoresis as one of the common antigens of the species . A polyclonal antiserum with a restricted specificity for HA-Ag2 was produced by immunizing with the relevant immunoprecipitate excised from crossed-immunoelectrophoresis gels . The immunoglobulin G fraction of this monospecific antiserum inhibited hemagglutination . The antiserum was used against a cell surface extract of B . gingivalis in immunoblotting experiments, and we detected two antigens with apparent molecular masses of 33 and 38 kilodaltons in B . gingivalis ATCC 33277 and W83 . Monoclonal antibody, C1.17, produced in another laboratory against B . gingivalis 381 and characterized as showing reactivity with a hemagglutinin of this strain (Y . Naito, K . Okuda, T . Kato, and I . Takazoe, Infect . Immun . 50:231-235, 1985), was also used to produce immunoblots of extracts of strains ATCC 33277 and W83 . The apparent molecular masses of the major polypeptides recognized by monoclonal C1.17 in the immunoblots were the same as those detected by the polyclonal monospecific antiserum, i.e., 33 and 38 kilodaltons . Significantly, none of the polypeptides identified in this study corresponded to the polypeptide appearing in the 41- to 43-kilodalton region and identified by Yoshimura and co-workers (F . Yoshimura, K . Takahashi, N . Yoshinobu, and T . Suzuki, J . Bacteriol . 160:949-957, 1984) as the fimbrial protein characteristic of the species . Enzyme-linked immunosorbent assay inhibition experiments with the monospecific antiserum indicated that the cell surface extracts from strains ATCC 33277 and W83 were strong inhibitors, whereas the fimbria-enriched preparations from both strains failed to inhibit binding of antibodies to the cell surface antigens . As a whole, our study indicates that a nonfimbrial surface protein complex demonstrating erythrocyte-binding capacity, HA-Ag2, is common to three strains of B . gingivalis and is composed of at least two associated polypeptides with apparent molecular masses of 33 and 38 kilodaltons which share at least one antigenic determinant.

Immunol Cell Biol, 1989 Feb, 67 ( Pt 1), 71 - 8
Monoclonal antibodies defining immunogenic regions of pili from Bacteroides nodosus strains 198 (A1), 265 (H1) and 336 (F1); Young D et al.; A total of 17 monoclonal antibodies (MoAb) were used to analyse the antigenic structure of pilus protein from three serogroups of Bacteroides nodosus . The four MoAb which agglutinated pili were serogroup (and subgroup) specific, and the agglutinating epitope was present on the pili monomer and dependent on the intra-chain disulfide bond . Non-agglutinating MoAb identified two further non-linear and serogroup-restricted epitopes on strain 198 (A1) pili and two linear epitopes on 336 (F1) and 265 (H1) pili . Three MoAb cross-reacted with pili from six of the eight major serogroups and recognized an epitope in the N-terminal region of the molecule . This panel of MoAb has therefore identified at least four epitopes on pilus protein and will facilitate serotopic analyses of the immunogenicity of each epitope in sheep during vaccination against footrot.

J Biol Chem, 1989 Jan 15, 264(2), 872 - 83
Structures of neutral O-linked polylactosaminoglycans on human skim milk mucins . A novel type of linearly extended poly-N-acetyllactosamine backbones with Gal beta(1-4)GlcNAc beta(1-6) repeating units; Hanisch FG et al.; O-Linked oligosaccharides were isolated from human skim milk mucins and from mucin-derived glycopeptides by reductive beta-elimination . The released alditols were fractionated by DEAE-Sephadex chromatography and purified by high performance liquid chromatography on primary amine bonded phase . The structures of the major neutral oligosaccharide alditols could be established by fast atom bombardment and electron impact mass spectrometry, combined with methylation analysis, 500-MHz 1H nuclear magnetic resonance spectroscopy, and endo-beta-galactosidase (from Bacteroides fragilis, EC 3.2.1.103) digestion (where n = 0-3): (formula; see text) Major O-glycosidically linked oligosaccharides on skim milk mucins are of the Gal beta(1-3){GlcNAc beta(1-6)} GalNAc core type 2 and exhibit linearly extended backbone chains of the poly N-acetyllactosamine type comprizing up to at least four repeating units, which are linked by the hitherto unknown sequence GlcNAc-beta(1-6) Gal rather than GlcNAc beta(1-3)Gal . A considerable portion of neutral alditols is represented by branched isomers of the linear species, which are distinguished by their content of 3,6-disubstituted galactose and their partial resistance to endo-beta-galactosidase digestion.

J Clin Periodontol, 1989 Jan, 16(1), 38 - 45
Treatment of recurrent periodontal disease by root planing and Ornidazole (Tiberal) . Clinical and microbiological findings; Mombelli A et al.; The purpose of this study was to evaluate the use of Ornidazole as an adjunct to root planing in the therapy of patients suffering from recurrent periodontal disease . In 10 individuals who had previously been treated with scaling, root planing and periodontal surgery and who had followed a regular maintenance program including recall visits every 3-5 months for 1-7 years, 2 sites with recurrent periodontitis and 1 shallow site were selected . Reinfected sites had a record of losing clinical attachment of more than 3 mm since the completion of initial therapy, were bleeding upon probing and had a mean pocket probing depth of 7.85 +/- 1.31 mm . They had been reinstrumented several times by a registered dental hygienist, when clinical signs of recurrence of disease had appeared and the root surfaces were judged to be smooth and free of deposits . Clinical parameters were recorded and microbial samples were collected twice prior to retreatment . Then, 500 mg Ornidazole, to be taken twice a day for 10 days, was administered, and the whole dentition was thoroughly scaled and root planed . At day 10 as well as 2, 5, 8 and 11 months thereafter, samples were again obtained . At baseline, reinfected sites showed over 20% spirochetes, over 20% motile rods and over 9% fusiform organisms in darkfield preparations of subgingival plaque samples . Culturally, over 1/10 of organisms were identified as black pigmenting Bacteroides and in 18% of all baseline samples collected, B . gingivalis was found.(ABSTRACT TRUNCATED AT 250 WORDS)

J Med Microbiol, 1989 Jan, 28(1), 5 - 8
Cytotoxic activity of crude extracts of Bacteroides gingivalis; Eke PI et al.; The cytotoxic activities of culture supernates, crude cell extracts and cell-wall materials of Bacteroides gingivalis were investigated in vitro . Each component was cytotoxic to Vero cells and, to a lesser extent, Wi 38 cells . The cytotoxic agents had similar effects on the cell lines to butyric acid, propionic acid and a partially-purified trypsin-like protein extracted from a clinical isolate of B . gingivalis; the effects were eliminated by heat . Cytotoxic materials obtained from young cultures were more susceptible to heat than those from older cultures . The heart-labile substance inside and outside the bacterial cell in young cultures of B . gingivalis may contribute to its overall cytotoxic activity.

Infection, 1989, 17 Suppl 1, S11 - 3
{Susceptibility of clinically important Bacteroides species against enoxacin-metronidazole and enoxacin-clindamycin combinations}; Heizmann WR et al.; To assess the activity of enoxacin, clindamycin and metronidazole, MICs of clinical isolates of saccharolytic intestinal Bacteroides spp . were determined, using the agar dilution method according to NCCLS guidelines . Checkerboard titrations of enoxacin-metronidazole and enoxacin-clindamycin were done on Wilkins-Chalgren agar; inoculation, incubation and reading of plates were as for determination of MICs . Metronidazole MIC 90s for Bacteroides fragilis (23 strains) and Bacteroides thetaiotaomicron (23 strains) were 0.5 mg/l, clindamycin MIC 90 for B . fragilis was 1 mg/l, and for B . thetaiotaomicron 8 mg/l, whereas enoxacin MIC 90 values were 16 mg/l and 64 mg/l, respectively . The evaluation of the inhibitory effects of the combination enoxacin-metronidazole for B . fragilis showed additional effects in eleven strains, indifference in seven strains and antagonism in one . The figures for B . thetaiotaomicron showed addition in five strains, indifference in 17 strains, antagonism in one . For B . fragilis the combination enoxacin-clindamycin showed addition in ten strains, indifference in six, and antagonism in one; for B . thetaiotaomicron synergism in one strain, addition in four strains, indifference in 17 strains . In conclusion, the absence of antagonism and the overall preponderance of additional and indifferent effects warrant the use of enoxacin in combination with metronidazole or clindamycin in clinical trials of treatment of anaerobic-aerobic mixed infections.

Free Radic Res Commun, 1989, 6(6), 359 - 67
Free radical generating mechanisms in the colon: their role in the induction and promotion of colorectal cancer?
Blakeborough MH, Owen RW, Bilton RF.
A hypothesis is presented to account for the dietary induction and promotion of colorectal cancer . The principal agents are the secondary bile acids, lithocholic and deoxycholic acids, the vitamin K group and ferrous iron complexes . These metabolites may interact to subvert the normal free radical generating mechanisms involved in mucosal defence . Diets high in fat and red meat and low in fibre support a Bacteroides-dominated colonic microflora, which both synthesis and utilises vitamin K2 isoprenalogues or menaquinones as enzyme co-factors . Iron(II) complexes such as haemin from the breakdown of dietary haemoglobin and myoglobin also serve as growth factors for these bacteria and provide a rich source of haem-iron for intestinal uptake . Biliary secretion is stimulated by dietary fat and bile acids are essential for the intestinal uptake of vitamin K and possibly of iron complexes such as haemin . In the mature colonocyte, vitamin K and haemin may initiate redox cycling reactions which liberate superoxide (O2-.) . Bile acids can activate the membrane bound phospholipase to liberate arachidonate and diacylglycerol . This leads in turn to the production of more O2- . which can enter the microcirculation and acts as a potent chemoattractant for the neutrophils that line the lamina propria . The released diacylglycerol can activate protein kinase C in the neutrophil membrane to switch on the respiratory burst oxidase system generating yet more O2- . and may stimulate the proliferation of transformed stem cells by a similar protein kinase C mediated mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

Int J Biochem, 1989, 21(6), 661 - 6
Detection of 2-keto-3-deoxyoctonate in endotoxins isolated from six reference strains of the Bacteroides fragilis group; Beckmann I et al.; 1 . Endotoxins isolated from six serotype specific reference strains of the Bacteroides fragilis group were dephosphorylated by treatment with aqueous 50% hydrofluoric acid . 2 . Mild acidic hydrolysis of the dephosphorylated endotoxins released 2-keto-3-deoxyaldonic acid, the presence of which was demonstrated by the colorimetric thiobarbituric acid assay (TBA) . 3 . Thin layer chromatography of the dephosphorylated lipopolysaccharide of B . fragilis IPL E 323 (serotype E2), after acidic hydrolysis, revealed a TBA-positive substance with the same Rf-value as authentical 2-keto-3-deoxyoctolusonic acid (KDO) . 4 . Quantification of 2-keto-3-deoxyoctonate-in the lipopolysaccharide of B . fragilis IPL E 323 by means of the TBA resulted in a KDO content of 15 nM mg-1 lipopolysaccharide.

Life Sci, 1989, 44(1), 35 - 40
Phenytoin induces interleukin-1 production in vitro; Modeer T et al.; Human adherent mononuclear cells and subcloned cell lines established from the human histiocytic cell line U-937 were cultured with phenytoin (PHT) and/or lipopolysaccharide (LPS) purified from Bacteroides fragilis . After the cultivation period, the cell-free supernatants were tested for interleukin-1 (Il-1) activity . The results showed that PHT induces Il-1 activity and potentiates LPS-induced Il-1 production . In the monocytic cell line U-937, the induced Il-1 production was found to be clonally distributed indicating that the response to PHT may be exerted by a subpopulation of monocytes . The PHT-induced Il-1 activity may be of importance in the development of gingival overgrowth . The induced Il-1 could also contribute to other known side effects such as dermatologic reactions accompanied by transient fever seen in patients medicating the drug.

Chemotherapy, 1989, 35(3), 153 - 9
Influence of environmental factors on the in vitro efficacy of ciprofloxacin against anaerobic bacteria; Thadepalli H et al.; The effects of alterations in pH, size of inoculum, addition of human serum, and repeated exposure to sub-minimum inhibitory concentration of ciprofloxacin against anaerobic bacteria were assessed . Increase in the size of the inoculum and human serum had no effect on the minimum inhibitory concentration, whereas decrease in pH and exposure to sub-MIC decreased the activity of ciprofloxacin against Bacteroides fragilis . We tested for synergism of ciprofloxacin with cefoxitin, clindamycin and metronidazole against B . fragilis.

J Antimicrob Chemother, 1989 Jan, 23(1), 99 - 106
Pharmacokinetics and pharmacodynamics of total and unbound cefoxitin and cefotetan in healthy volunteers; Carver PL et al.; Cefotetan is a semisynthetic cephalosporin with a broad spectrum of Gram-negative and anaerobic activity . We compared the pharmacokinetics and serum inhibitory activity of 2 g doses of cefotetan and cefoxitin in six healthy volunteers . The half-life of cefotetan (176 min) was significantly longer than that of cefoxitin (49 min) . Despite higher protein binding (85% versus 50%), free cefotetan serum concentrations 12 h post dose (1.6 mg/l) were higher than free cefoxitin serum concentrations 6 h post dose (0.32 mg/l) . Total and free serum inhibitory titres for Escherichia coli were greater than 1:8 for 12 h post dose for cefotetan, but only 1 h post dose for cefoxitin . Against Bacteroides fragilis, neither cefoxitin nor cefotetan exhibited free serum inhibitory titres greater than 1:8 at the end of their respective dosing intervals . However, cefotetan titres were equivalent or superior to those of cefoxitin over the entire 6 or 12 h dosing interval . Despite relatively high protein binding, cefotetan demonstrates comparable or superior activity 12 h after dosing to cefoxitin 6 h after dosing . More studies comparing the clinical outcome of cefoxitin and cefotetan are needed but our results support the clinical recommendations that cefoxitin should be given every 6 h, and cefotetan every 12 h.

Immunol Invest, 1989 Jan-May, 18(1-4), 225 - 37
Effects of immunization with B . macacae on induced periodontitis--preliminary findings; Nisengard R et al.; This preliminary study examined the effects of immunization with Bacteroides macacae, the monkey equivalent of the human species of B . gingivalis on ligature-induced periodontitis . During a 12 week immunization period, 8 out of the 12 Macacae fasicularis monkeys were immunized weekly with B . macacae washed cells and 4 were sham-immunized with saline . At the same time, all were scaled and pumiced weekly to establish gingival health . Following this period, the mandibular first molars were ligated in 8 out of the 12 monkeys to induce periodontitis . The immunized, ligated experimental group, the ligated, sham-immunized control group, and the immunized, non-ligated control group were then followed for a 6 months ligation period while plaque was allowed to accumulate . Gingival indices, attachment levels, pocket depths, plaque indices, radiographs, serum and crevicular fluid antibodies and subgingival bacteria were assessed . Immunization led to elevated antibody levels to B . macacae while ligation increased plaque, gingival inflammation, and bone loss . Following the 6 month ligation period, B . macacae comprised 1.7% of the cultivable flora in the immunized, non-ligated monkeys, 2.1% in the immunized, ligated monkeys, and 5.6% in the sham-immunized, ligated monkeys . Similar differences between the immunized, ligated and and the sham-immunized, ligated groups were not seen for B . intermedius, nor B . melaninogenicus . These results suggest a heightened humoral response to B . gingivalis reduces subgingival re-colonization by this organism and modulates the course of ligature-induced periodontitis.

Immunol Invest, 1989 Jan-May, 18(1-4), 171 - 85
Antigens released from four oral bacteria in periodontitis; Tolo K et al.; Antigens fractionated from cultures of four oral bacteria were tested for binding of serum IgG, IgA and IgM from patients in early and established phase of periodontitis . Bacteroides gingivalis and A.actinomycetemcomitans released antigens that discriminated between serum from individuals with or without periodontitis . The discriminating antigens ranged from 10 to 43 kDa and included neutral sugar and protein but no lipids . Significantly increased levels of IgG and IgA antibodies to the antigens released from B . gingivalis were detected before bone loss was seen and predicted such disease progression.

Pediatr Med Chir, 1989 Jan-Feb, 11(1), 93 - 6
{Post-traumatic inflammatory pseudotumor of the lung . Description of a case}; Freschi P et al.; Inflammatory pseudotumor (P.I.) of the lung is a rare benign lesion histologically characterized by a variety of inflammatory and mesenchymal cells (plasma cells, lymphocytes and histiocytes) . The etiology remains obscure . We report a case of P.I . occurred immediately after a thoracic trauma . The infectious etiology is suggested by the growth of an anaerobic microorganism (Bacteroides) in tissue culture.

FEMS Microbiol Lett, 1989 Jan 1, 48(1), 93 - 6
Glycylprolyl dipeptidase activity of Bacteroides gingivalis W50 and the avirulent variant W50/BEI; Kay HM et al.; Glycylprolyl dipeptidase activity was measured in cells, extracellular vesicles (ECV) and the soluble extracellular protein fraction (EP) of batch cultures of strains W50 and W50/BEI . Total culture enzyme activity of W50 dropped with age whilst that of W50/BEI remained constant . Activity was highest in the cellular fraction, greater for W50/BEI than W50 and rose with culture age . Both strains showed similar ECV activities but these declined with culture age . The EP glycylprolyl dipeptidase activity of W50/BEI in older cultures rose to a level 13-fold greater than W50 . The majority of extracellular activity was represented by the ECV for strain W50 but by EP for W50/BEI . Variable but incomplete attenuation of activity was achieved by dithiothreitol . ECV and EP activities were associated with a high molecular mass fraction, but a smaller fraction (molecular mass 30,000) was detected in W50/BEI EP.

Diagn Microbiol Infect Dis, 1989 Jan-Feb, 12(1), 45 - 50
Comparison of the in vitro action and interaction of cefotaxime and desacetylcefotaxime against clinical isolates of Bacteroides spp; Aldridge KE; Desacetylcefotaxime (dCTX), the in vivo metabolite of cefotaxime (CTX), possess significant in vitro antimicrobial activity similar to the parent compound against a variety of aerobic and anaerobic bacteria . In vitro susceptibility studies showed that CTX inhibited 86% of 473 strains of the Bacteroides fragilis at a concentration of 32 micrograms/ml while dCTX inhibited 91% of the test isolates at the same concentration . Strains of the B . fragilis species were significantly more susceptible to CTX than were the non-B . fragilis species . Susceptibility testing of CTX and dCTX in a 1:1 ratio produced significantly more inhibitory activity, especially against the non-B . fragilis strains . Synergy studies showed that the interaction of CTX and dCTX was either completely or partially synergistic against 85% of 92 test organisms . The presence of dCTX was also shown to lower the CTX MIC values four-fold or greater in 82% of the synergy studies . Synergy was noted against strains of the B . fragilis group, B . melaninogenicus group, B . bivius, B . disiens, and B . capillosus . Through the use of time-kill kinetics studies, the interaction of CTX and dCTX was shown to be additive at subinhibitory and inhibitory concentrations and suggestedly synergistic at suprainhibitory concentrations against strains of the B . fragilis group . These in vitro studies demonstrate that dCTX increases the inhibitory and bactericidal activity of CTX when tested in combination.

Diagn Microbiol Infect Dis, 1989 Jan-Feb, 12(1), 39 - 43
Effectiveness of cefotaxime alone and in combination with desacetylcefotaxime against Bacteroides fragilis; Wasilauskas BL; The synergistic activity of the combination cefotaxime-desacetylcefotaxime (CTX/dCTX) was compared to the effectiveness of seven other antimicrobial agents: cefoxitin (CFOX), cefotetan (CTAN), ceftizoxime (CTIZ), chloramphenicol (CLOR), clindamycin (CLIND), metronidazole (METR), and ampicillin-sulbactam (A/S) tested against 100 clinical isolates belonging to the Bacteroides fragilis group . All tests were performed using the NCCLS reference agar-dilution method . The overall susceptibility of these organisms to CTX/dCTX was 84% compared to CFOX at 78% or CTAN at 66% . The other antimicrobials inhibited greater than 90% of these isolates . There was no difference between the susceptibility rates of CTX/dCTX and CTX with the B fragilis (85%) or B . distasonis (75%) strains . Bacteroides thetaiotaomicron showed a 11% greater susceptibility to CTX/dCTX than to CTX . Of the 100 isolates tested, 40% showed either synergy or partial synergistic interactions between CTX and dCTX . Most of the isolates showed indifference (52%), while 8% demonstrated antagonism; a relatively unique finding to date.

Diagn Microbiol Infect Dis, 1989 Jan-Feb, 12(1), 33 - 7
Comparative in vitro activity of cefoxitin, cefotaxime alone, and in combination with desacetylcefotaxime against the Bacteroides species; Canawati HN; The agar dilution method was used to determine the inhibitory activity of cefotaxime (CTX) alone, desacetylcefotaxime (dCTX) alone, CTX plus dCTX, and cefoxitin against 74 clinical isolates of the Bacteroides species recovered from diabetic patients with foot ulcers . The study concluded that the addition of dCTX to CTX increased the inhibitory activity from 45% to 73% for all strains tested and from 50% to 81% among the 32 strains of Bacteroides fragilis . This synergistic interaction against B . fragilis resulted in a four- to nine-fold reduction in the MIC of seven strains (64-128 micrograms/ml, resistant category MICs) . While the lowest CTX MIC for B . fragilis was 2 micrograms/ml (four strains), the addition of dCTX also produced a remarkable reduction in susceptible range CTX MICs to 0.05-2 micrograms/ml in 16 strains (50%) . The overall susceptibility to cefoxitin and CTX plus dCTX was as follows: 100% and 100% for Bacteroides vulgatus, 50% and 66% for Bacteroides thetaiotaomicron, 100% and 33% for Bacteroides ovatus, and 83% and 82% for Bacteroides species other than the B . fragilis group.

Appl Environ Microbiol, 1989 Jan, 55(1), 148 - 53
Ruminal cellulolytic bacteria and protozoa from bison, cattle-bison hybrids, and cattle fed three alfalfa-corn diets; Varel VH et al.; Ruminal cellulolytic bacteria and protozoa and in vitro digestibility of alfalfa fiber fractions were compared among bison, bison hybrids, and crossbed cattle (five each) when they were fed alfalfa and corn in a ratio of 100:0, 75:25, and 50:50, respectively . The total number of viable bacteria (2.16 x 10(9) to 5.44 x 10(9)/ml of ruminal fluid) and the number of cellulolytic bacteria (3.74 x 10(7) to 10.9 x 10(7)/ml) were not different among groups of animals fed each diet . The genera of protozoa in all of the animal groups were similar; however, when either the 100:0 or 50:50 diet was used the percentage of Entodinium sp . was lower and the percentage of Diplodiniinae was higher (P less than 0.05) in bison than in bison hybrids or cattle . Bacteroides succinogenes made up the largest number of cellulolytic isolates from bison (58 and 36%, respectively, on the 100:0 and 75:25 diets), which were more numerous (P less than 0.05) than those from bison hybrids (36 and 12%) and cattle (33 and 18%) . This was offset by a lower number of cellulolytic Butyrivibrio isolates . The numbers of Ruminococcus albus and R . flavefaciens isolates, in general, were similar among the bovid species, although R . flavefaciens generally made up less than 10% of the cellulolytic isolates . In vitro digestibility coefficients were greater (P less than 0.05) for the bison when the 75:25 diet was used and similar for the other two diets . The concentration of ruminal volatile fatty acids was larger (P less than 0.05) in bison than in bison hybrids and cattle when the 50:50 diet was used.(ABSTRACT TRUNCATED AT 250 WORDS)

Scand J Infect Dis Suppl, 1989, 62, 15 - 24
Virulence determinants in nonsporeforming anaerobic bacteria; Hofstad T; The literature dealing with adherence, host-protective mechanisms and tissues damaging products of nonsporeforming anaerobes is reviewed . The adherence mechanisms are poorly understood . There is evidence for that encapsulation plays a role in the pathogenicity of Bacteroides fragilis and black-pigmented bacteroides . A leukocidin is produced by Fusobacterium necrophorum, and Ig protease, collagenase and a trypsin-like enzyme by some Bacteroides species . Some Bacteroides fragilis strains produce an enterotoxin . The pathogenetic role of endotoxin is unclear.

Rev Belge Med Dent, 1989, 44(2), 9 - 30
{Bacterial invasion in periodontitis, is it important in periodontal treatment?}; Adriaens PA; During the progression of periodontal disease bacteria invade the epithelial lining of the gingival pocket and the underlying connective tissue . This invasion was demonstrated in acute necrotizing ulcerative gingivitis (ANUG), localized juvenile periodontitis (LJP), rapidly progressive periodontitis in adults (RPP) and in children with Papillon-Lefevre syndrome associated periodontitis . Using morphologic criteria or fluorescent antibody staining techniques spirochetes, Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B . intermedius, Actinomyces species, Fusobacterium nucleatum and Mycoplasma have been identified in these tissue compartments . Recent light microscopic, electron microscopic and bacteriological studies demonstrated the presence of invading bacteria in the cementum and in the radicular dentin of teeth with periodontal disease . In 83% of 69 carries free periodontally diseased teeth bacteria were present in one of the dentin layer from the root . In 59% of these teeth the dental pulps contained bacteria . The composition of the flora resembled that of the subgingival flora . The use of chlorhexidine, fluoride, tetracyclines or metronidazole in the elimination of invading bacteria following mechanical periodontal therapy is discussed.

Int Arch Allergy Appl Immunol, 1989, 90(1), 24 - 30
Modulation of human neutrophil adherence by periodontopathic bacteria: reversal by specific monoclonal antibodies; Seow WK et al.; Previous investigations by us have shown that direct interaction of Fusobacterium nucleatum with polymorphonuclear neutrophils (PMNs) results in the stimulation of PMN adherence whereas direct interaction with Bacteroides gingivalis results in PMN suppression . In the present study, panels of monoclonal antibodies (MAbs) raised against cell wall antigens of F . nucleatum and B . gingivalis were tested to determine their ability to block the modulatory effects of the bacteria in their interactions with PMNs . While no activity was demonstrated for any of the 9 MAbs raised against F . nucleatum, it was found that 2 of 16 MAbs raised against B . gingivalis were able to reverse the suppression of PMN adherence induced by the bacteria . Further studies on these 2 reactive MAbs showed that the effect of MAbs were abrogated by heat treatment as well as by trypsin proteolysis . Investigations into the nature of the reactive epitopes on the bacterial surface showed that they probably contain protein components susceptible to proteolytic attack by subtilisin . In addition, beta-galactose may be a component of the reactive epitopes for one of the MAbs, but sialic acid residues on the bacterial surface are probably not involved as their elimination by neuraminidase did not affect the binding of both MAbs . The results of the present study strongly validate our previous observations that direct specific interaction of B . gingivalis with human PMNs occurs, resulting in the suppression of PMNs.

Appl Environ Microbiol, 1989 Jan, 55(1), 132 - 6
Molecular cloning and expression in Escherichia coli of a cellodextrinase gene from Bacteroides succinogenes S85; Gong JH et al.; A DNA fragment coding for a cellodextrinase of Bacteroides succinogenes S85 was isolated by screening of a pBR322 gene library in Escherichia coli HB101 . Of 100,000 colonies screened on a complex medium with methylumbelliferyl-beta-D-cellobioside as the indicator substrate, two cellodextrinase-positive clones (CB1 and CB2) were isolated . The DNA inserts from the two recombinant plasmids were 7.7 kilobase pairs in size and had similar restriction maps . After subcloning from pCB2, a 2.5-kilobase-pair insert which coded for cellodextrinase activity was isolated . The enzyme was located in the cytoplasm of the E . coli host . It exhibited no activity on carboxymethyl cellulose, Avicel microcrystalline cellulose, acid-swollen cellulose, or cellobiose but hydrolyzed p-nitrophenyl-beta-D-cellobioside and p-nitrophenyl-beta-D-lactoside . The Km (0.1 mM) for the hydrolysis of p-nitrophenyl-cellobioside by the enzyme expressed in E . coli was similar to that reported for the purified enzyme from B . succinogenes . Expression of the cellodextrinase gene was subjected to catabolite repression by glucose and was not induced by cellobiose . The origin of the DNA insert from B . succinogenes was confirmed by Southern blot analysis . Western blotting (immunoblotting) using antibodies raised against the purified B . succinogenes cellodextrinase revealed a protein with a molecular weight of approximately 50,000 in E . coli clones which comigrated with the native enzyme isolated from B . succinogenes . These data indicate that the cellodextrinase gene expressed in E . coli is fully functional and codes for an enzyme with properties similar to those of the native enzyme.

J Bacteriol, 1989 Jan, 171(1), 148 - 53
Novel aerobic tetracycline resistance gene that chemically modifies tetracycline; Speer BS et al.; A tetracycline resistance gene that was found originally on the Bacteroides plasmid pBF4 confers resistance on Escherichia coli but only when cells are growing aerobically . When E . coli EM24 carrying this aerobic tetracycline resistance (*Tcr) gene is grown in medium containing tetracycline, the resulting spent medium is no longer toxic to tetracycline-sensitive (Tcs) E . coli EM24 (B.S . Speer and A.A . Salyers, J . Bacteriol . 170: 1423-1429, 1988) . To determine whether the *Tcr gene product modified tetracycline, we characterized the material resulting from incubation of E . coli (*Tcr) with tetracycline . When {7-3H(N)}tetracycline was added to cultures of E . coli (*Tcr), at least 90% of the label was recovered in the extracellular fluid . Therefore, tetracycline was not being sequestered by the cells . The labeled material behaved similarly to tetracycline with respect to solubility in various organic solvents . However, the UV-visible light spectrum had a single peak at 258 nm, whereas the tetracycline spectrum had a peak at 364 nm . The labeled material also had a faster migration rate than did tetracycline on thin-layer plates in a solvent system of butanol-methanol-10% citric acid (4:1:2, vol/vol/vol) and was separable from tetracycline by reverse-phase high-pressure liquid chromatography, using an acetronitrile-0.1% trifluoroacetic acid solvent system . These results demonstrate that the *Tcr gene product chemically modifies tetracycline . The *Tcr gene is the first example of a chemically modifying tetracycline resistance mechanism.

Arch Oral Biol, 1989, 34(9), 679 - 83
Interleukin-1 and interleukin-1 inhibitor production by human adherent cells stimulated with periodontopathic bacteria; Walsh LJ et al.; This study examined the effect of the putative periodontopathic bacteria Bacteroides gingivalis and Fusobacterium nucleatum on the production of interleukin-1 (IL-1) and IL-1 inhibitors by human plastic-adherent mononuclear cells from normal donors . Fusobacterium mortiferum was used as a non-oral, non-pathogenic control organism . Unstimulated adherent cells spontaneously secreted an IL-1 inhibitor, whereas stimulation with B . gingivalis induced the synthesis and secretion of IL-1 . With both fusobacteria IL-1 was present in the intracellular environment, whereas the predominant secretory product was either IL-1 or an IL-1 inhibitor . These results suggest that bacteria are capable of modulating cytokine production by monocytes and may thereby alter the local immune response.

J Endod, 1989 Jan, 15(1), 13 - 9
Prevalence of black-pigmented bacteroides species in root canal infections; Sundqvist G et al.; The prevalence of black-pigmented Bacteroides species in the root canals of 72 teeth with apical periodontitis was evaluated . Twenty-two of the canals contained one or more species of black-pigmented Bacteroides . Bacteroides intermedius (14 strains) and Bacteroides endodontalis (5 strains) were most common . Of the species Bacteroides gingivalis, Bacteroides loeschei, and Bacteroides denticola, 2, 3, and 1 strains, respectively, were isolated . The median number of bacterial cells recovered from the root canals containing black-pigmented Bacteroides was 2.8 x 10(5) and from the other canals 3.0 x 10(3) . The mean number of strains was 7.9 and 3.3, respectively . Sixteen of the 22 root canals containing black-pigmented Bacteroides species were associated with acute apical abscesses and purulent drainage through the root canal . The other six teeth with black-pigmented Bacteroides were asymptomatic . One additional abscess was present among the 72 cases . This root canal contained Actinomyces israelii and Actinomyces naeslundii.

Arch Oral Biol, 1989, 34(7), 579 - 83
Collagenolytic activity of the extracellular vesicles of Bacteroides gingivalis W50 and an avirulent variant W50/BE1; Smalley JW et al.; The activities of the extracellular vesicle fractions of these two organisms were compared . Lytic activity against a native type I placental collagen substrate at 30 degrees C was assessed following sodium dodecyl sulphate-polyacrylamide gel electrophoresis and densitometry . A rapid rate of collagen depolymerization was achieved by the extracellular vesicle fraction of W50, yielding approx . 90% substrate degradation compared to 5% for W50/BE1 extracellular vesicles over 6 h incubation . The polypeptide digestion patterns produced by incubation with extracellular vesicle fractions of both organisms were identical, and similar to those yielded by incubation of substrate with whole W50 cells.

J Pedod, 1989 Spring, 13(3), 222 - 9
DNA probe detection of key periodontal pathogens in juveniles; Kisby LE et al.; Recognition of juvenile forms of periodontitis have been shown to be directly linked with specific Gram-negative rods, primarily Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Bacteroides intermedius . However, clinical application of these laboratory findings have generally been restricted to the research environment . The purpose of this study was to explore the relationship of these three pathogenic species in children using the reliable and accurate new technology of DNA probes . Results indicated that the pathogenic oral flora did not differ significantly between subjects with and without gingival inflammation . Therefore, tracking of pathogens using clinical parameters of inflammation are unreliable and accurate monitoring requires microbiological testing in order to properly identify the presence or absence of pathogens.

Scand J Infect Dis Suppl, 1989, 62, 29 - 34
Immune mechanisms in the prevention of intra-abdominal abscess formation; Kasper DL et al.; Bacteroides fragilis is the most commonly isolated anaerobe from intraabdominal infections . In experimental models of intraabdominal sepsis, B . fragilis has been shown to be uniquely virulent . Some of these virulence traits are due to the capsular polysaccharide of this organism . Immunity to infection secondary to B . fragilis seems to involve both arms of the immune system . Humoral immunity (complement, antibody and PMNs) is critical to clearance of these bacteria from the blood stream . Cellular immune mechanisms predominate against intraabdominal abscess formation . Adoptive transfer experiments have shown that a CD8+, IJ+, non H2 restricted immune T cell or lysate from this T cell confers protection to immunocompetent, naive mice . An in vivo system has been developed to begin defining the mechanism of protection . B . fragilis placed inside a filter containment chamber within the peritoneum of immune mice are specifically killed over an 8-day period in the absence of white blood cells . This killing phenomenon was also observed inside filter chambers within mice receiving adoptively transferred immune T cells or lysates of these T cells . Furthermore, killing is specific to B . fragilis . These results support a T cell dependent mechanism for killing this bacteria and provide an interesting model for further exploration.

Scand J Infect Dis Suppl, 1989, 62, 25 - 8
Mechanisms of antimicrobial resistance in anaerobic bacteria: the predictive approach; Baquero F et al.; Antibiotic resistance in anaerobic bacteria probably evolves from broadly undetected mechanisms of resistance, as the generally accepted breakpoints in susceptibility testing are mainly based on pharmacological grounds . Some of the strains considered susceptible by conventional techniques may harbour mechanisms of resistance . These resistant organisms should be screened using the antibiotic concentrations immediately above those inhibiting the fully susceptible population of a given species as breakpoints . The following break-points for bacteroides strains are suggested as definitions of the entirely susceptible population: piperacillin 8 mg/l; ceftizoxime 8 mg/l: cefoxitin 8-16 mg/l: imipenem 1 mg/l: ticarcillin-clavulanate 2 mg/l; clindamycin 1 mg/l: chloramphenicol 8 mg/l: tetracycline 4 mg/l: metronidazole 1 mg/l . Detection of an increased frequency of organisms presenting low-level resistance may be useful to predict and possibly control the appearance and spread of fully resistant anaerobic organisms.

Microbiol Immunol, 1989, 33(1), 75 - 80
Possibility of Bacteroides gingivalis hemagglutinin possessing protease activity revealed by inhibition studies; Nishikata M et al.; Inhibition of hemagglutinin (HA) activity in a membrane fraction of Bacteroides gingivalis was examined using various compounds . Leupeptin and anti-pain inhibited the HA activity at nM order . This potency was lost when the aldehyde group of leupeptin was converted to an alcohol moiety . Irreversible protease inhibitors, tosyl-L-lysine chloromethyl ketone (TLCK), p-chloromercuribenzoate (PCMB), and N-ethylmaleimide (NEM) were also inhibitory . From the inhibition experiments, we speculate that the HA possesses protease activity and that the same site of the molecule participates in the erythrocyte binding and the substrate binding.

J Med Microbiol, 1989 Jan, 28(1), 9 - 14
Aggregation by fragilis and non-fragilis Bacteroides strains in vitro; Blake M et al.; Bacteroides fragilis is associated with the formation of intra-abdominal abscesses, whereas other Bacteroides species are rarely involved . Since bacterial clumping may contribute to the survival of bacteria in the face of host defence mechanisms, the hypothesis has been put forward that differences in aggregation between fragilis and non-fragilis strains of Bacteroides may account for their differences in survival in vivo . All seven B . fragilis strains tested formed aggregates within 4 h, but strains not associated with intra-abdominal sepsis--B . vulgatus, B . thetaiotaomicron and B . distasonis--did not form aggregates in vitro . Aggregation occurred at 37 degrees C, but not at 4 degrees C or 20 degrees C . Treatment with pronase partially inhibited aggregation . Periodate treatment killed the cells and caused them to form clumps which were distinguishable from the control aggregates . Heat-killed B . fragilis cells formed similar distinct clumps, but cells killed by glutaraldehyde and formaldehyde did so to a lesser degree . No inhibition was found upon addition of carbohydrates, ethylenediaminetetraacetic acid or after treatment with trypsin . These results demonstrate that aggregate formation occurs with B . fragilis strains alone, and that surface proteins probably mediate this interaction.

Infect Immun, 1989 Jan, 57(1), 213 - 8
A protease of Bacteroides gingivalis degrades cell surface and matrix glycoproteins of cultured gingival fibroblasts and induces secretion of collagenase and plasminogen activator; Uitto VJ et al.; To assess the direct effects of Bacteroides gingivalis on periodontal cells, human gingival fibroblasts were cultured in the presence of B . gingivalis extracts or a trypsinlike enzyme partially purified from the bacteria by chromatography on benzamidine-Sepharose and Sephacryl S-200 . Analysis of cell surface glycoproteins by the periodate-{3H}borohydride labeling technique combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-fluorography demonstrated that fibronectin and some other high-molecular-weight cell surface glycoproteins were degraded by a 35,000-Mr(35K) B . gingivalis protease . Immunostaining of the fibroblast cultures showed degradation of intercellular matrix fibronectin by the 35K protease . The pattern of fibronectin degradation was monitored by examining the reaction products with the SDS-PAGE-immunoblotting technique . The protease degraded fibronectin rapidly and more extensively than did corresponding amounts of pancreatic trypsin . Collagenase secretion by the fibroblasts was assayed by incubating cell culture medium with soluble type I {3H}collagen at 25 degrees C followed by SDS-PAGE-fluorography analysis of the reaction products . The medium was also assayed for plasminogen activator activity by using a casein-agarose diffusion plate assay . The fibroblasts cultured with the 35K protease secreted increased amounts of collagenase and plasminogen activator into the medium . The results suggest that periodontal infection by B . gingivalis causes proteolytic damage of the host cell surface structures . Concomitantly, B . gingivalis may induce the cells to degrade their pericellular matrix.

Zahn Mund Kieferheilkd Zentralbl, 1989, 77(7), 659 - 67
{A latex agglutination test for the rapid identification of periodontally pathogenic microorganisms in subgingival plaque . The preliminary results}; Tsalikis L et al.; Latex agglutination tests (LA) have been evaluated for identifying periodontal pathogens . This preliminary study compared LA tests with indirect immunofluorescence (IF) for the rapid identification of A . actinomycetemcomitans, B . gingivalis, and B . intermedius in clinical subgingival plaque samples . A total of 58 sites from 12 patients suffering from advanced periodontitis, exhibiting recent attachment loss were examined before and after initial periodontal treatment . The results of the two examinations were pooled and a total of 116 sites were statistically evaluated . The overall agreement between LA and IF was 75.8% for black pigmented Bacteroides (BPB) and 74.1% for Aa . These results demonstrate the feasibility of LA as a rapid, inexpensive, and reliable tool for monitoring periodontal disease offered to the general practitioner.

J Periodontal Res, 1989 Jan, 24(1), 20 - 7
Failure of Bacteroides gingivalis W83 to accumulate bound C3 following opsonization with serum; Schenkein HA; Our previous studies have demonstrated that strains of Bacteroides gingivalis are capable of proteolytic degradation and inactivation of complement proteins including the third component of complement C3 . Since a crucial step in the ability of complement to control bacterial infections is the binding of C3 fragments to the bacterial surface with subsequent enhancement of phagocytosis, further examination of the importance of the proteolytic capacity of Bacteroides in interactions with complement proteins was carried out by quantitating the amount of C3 bound to two proteolytic Bacteroides gingivalis strains . Pooled normal human serum (NHS) containing 125I-C3 was incubated with strains of B . gingivalis (W83 and ATCC 33277) and the non-proteolytic pathogen A . actinomycetemcomitans strain Y4, and samples of the reaction mixtures were removed at various time intervals for determination of bound C3 . B . gingivalis 33277 bound only half the number of C3 molecules as did A . actinomycetemcomitans, while B . gingivalis W83 bound very little C3 . A large increase in the number of C3 molecules bound to B . gingivalis W83 was noted in assays carried out in the presence of the protease inhibitor TLCK, indicating that bacterial proteases may be responsible for the lack of binding of C3 to strain W83 . TLCK treatment modestly increased the accumulation of C3 on strain 33277, but had no effect on A . actinomycetemcomitans . Analysis of 125I-C3 in supernatants from reaction mixtures of strain 33277, W83, or a proteolytic strain of B . intermedius demonstrated no qualitative differences in the C3 fragments amongst the tested strains or in the presence or absence of TLCK.(ABSTRACT TRUNCATED AT 250 WORDS)

Eur J Clin Microbiol Infect Dis, 1989 Jan, 8(1), 83 - 5
Selective and differential medium for isolation of Bacteroides ureolyticus from clinical specimens; Eley A et al.; A new selective and differential medium for Bacteroides ureolyticus was compared with other commonly used selective media for anaerobes in a diagnostic trial with routine clinical specimens . All Bacteroides ureolyticus strains grew on nalidixic acid-teicoplaninurea agar, producing red colonies against a straw-coloured background . This medium was found to be the most selective for Bacteroides ureolyticus . In the diagnostic trial with 185 clinical specimens a 20% increase in the isolation rate of Bacteroides ureolyticus was obtained with this new medium.

Arch Oral Biol, 1989, 34(11), 911 - 6
Cleavage action of a trypsin-like protease from Bacteroides gingivalis 381 on reduced egg-white lysozyme; Endo J et al.; Soluble reduced lysozyme was extensively digested by a trypsin-like protease purified from the culture supernatant of the bacterium . The digestion peptides were separated and purified by reversed-phase high-performance liquid chromatography, and were subjected to amino acid analysis . The fragments were identified by their amino acid composition, and the cleavage sites in the lysozyme chain were determined . Like mammalian trypsin, the enzyme from B . gingivalis split peptide bonds non-specifically at carboxyl sides of internal arginine and lysine residues, but the lysine present at the amino terminus of the lysozyme chain was not released . In addition, the enzyme cleaved the peptide linkage at the amino side of lysine and bonds between leucine-glycine, alanine-leucine and leucine-serine . Thus the trypsin-like protease from B . gingivalis has some cleavage actions on lysozyme different from those of mammalian trypsin.

Meikai Daigaku Shigaku Zasshi, 1989, 18(2), 187 - 96
{Biological characterization of Bacteroides intermedius specific monoclonal antibody}; Satoh T et al.; One monoclonal antibody (BIF6) directed against Bacteroides intermedius Group I was developed by hybridoma technology . In the present study, we used culture medium from BIF6 antibody-producing cells to characterize the antibody . Its reactivity against B . intermedius (Group I, II), B . gingivalis, B . corporis, B . melaninogenicus, B . loescheii, and B . asaccharolyticus was detected by the enzyme-linked immunosorbent assay . BIF6 monoclonal antibody specifically reacted with B . intermedius Group I, but not with B . intermedius Group II . Also, the BIF6 did not react with other black-pigmented Bacteroides . Since BIF6 antibody reacted with some clinical isolates from subgingival plaques of adult periodontal patients, we suggest that this antibody may be useful as a tool in the clinic to identify B . intermedius Group I . Specific antigen of B . intermedius Group I recognized by BIF6 antibody was located on the outer membrane of the organism . And the specific antigen was inactivated by treatment for 20 min at 80 degrees C and at pH2 and 12 . Also the antigen was sensitive to trypsin treatment.

Medicina (B Aires), 1989, 49(4), 357 - 9
{Bacteroides distasonis meningitis}; Santoianni JE et al.; A 50 year old woman while undergoing severe treatment for rheumatoid arthritis, developed anaerobic meningitis . The cerebrospinal fluid (CSF) sample was transported and cultivated aerobically and anaerobically . After 48 h at 37 degrees C the anaerobically incubated plate, the enriched fluid thioglycollate medium and the anaerobic culture medium yielded luxuriant growth of an anaerobic Gram negative bacillum . The biochemical and antimicrobial susceptibility patterns were consistent with those for Bacteroides distasonis . Most of the strains of the 5 species included in the Bacteroides fragilis group (B . fragilis, B . vulgatus, B . ovatus, B . thetaiotaomicron and B . distasonis) are resistant to penicillins, cephalosporins of first generation and aminoglycosides . Anaerobic polyresistant flora from an intraabdominal focus (chronic cholecystitis) might have been selected by treatment with gentamicin and cephalotin, and proliferated into meningeal dissemination . It is important that CSF from immunocompromised patients with acute or chronic pulmonary, intraabdominal or cranium-facial infectious processes be transported and cultured in aerobic and anaerobic conditions . These patients must be treated with an initial therapeutic scheme that includes an effective antibiotic for the anaerobic microorganism that may be involved.

Acta Microbiol Pol, 1989, 38(3-4), 285 - 91
The cell-surface components of Bacteroides thetaiotaomicron as coating antigens in ELISA test; Rokosz A et al.; Cell-surface antigens were extracted out of three Bacteroides thetaiotaomicron strains of different origin . Lipopolysaccharides, their fractions, L1 preparations and capsular antigen were obtained . All substances were tested as coating antigens in ELISA test against antibacterial rabbit immune sera . The highest absorbances were observed with lipopolysaccharides (LPS), their polysaccharide fractions (PS) and capsular material (CPS) . Lipopolysaccharides after nuclease treatment (N-LPS), free from nucleic acids, were more active than crude phenol-water extracts (PW-LPS).

Acta Microbiol Pol, 1989, 38(2), 171 - 6
Serological studies of Bacteroides vulgatus from normal gut flora; Meisel-Mikolajczyk F et al.; A serological classification scheme for 48 strains of Bacteroides vulgatus was established by agglutination technique . Bacterial strains were isolated in our laboratory from gut flora of healthy persons . Absorbed antisera to 11 strains of B . vulgatus were prepared . All 48 strains tested reacted with one or more antisera . Among these strains, 22 serogroups were formed; 11 of them contained only one group component and 11 were made up of multiple group components.

Infect Immun, 1989 Jan, 57(1), 95 - 9
Characterization of sodium dodecyl sulfate-stable Bacteroides gingivalis proteases by polyacrylamide gel electrophoresis; Grenier D et al.; Profiles of the proteolytic activities found in Bacteroides gingivalis culture supernatants, outer membranes, vesicles, and cell extracts were analyzed in sodium dodecyl sulfate-polyacrylamide gels containing covalently bound bovine serum albumin . A total of eight distinct bands of proteolytic activity could be detected . Four of these were found in the culture supernatant (P1, P2, P3, and P4) . The outer membranes, vesicles, and the cell extract each contained seven major proteolytic bands (P1, P3, P4, P5, P6, P7, and P8) . No activity was found in the membrane-free extract, suggesting that the proteases were associated with the cell envelope . With the exception of P7 and P8, all the proteolytic bands were dependent on reducing agents for activity . The eight proteolytic bands were distributed in an identical manner in all four strains of B . gingivalis studied . The effects of protease inhibitors, pH, and heat were determined . Sulfhydryl group reagents and N-alpha-p-tosyl-L-lysine chloromethyl ketone reduced proteolytic activity . The optimum pH was found to be between 7 and 8 . A 30-min preincubation at 50 degrees C inactivated the P6, P7, and P8 proteolytic bands . All proteolytic activity was lost after the samples were heated at 75 degrees C for 30 min.

J Chromatogr, 1988 Dec 28, 459, 331 - 5
Rapid identification of Bacteroides species by high-performance liquid chromatography; Radin L et al.; High-performance liquid chromatography was evaluated for the rapid identification of Bacteroides species of clinical interest . Each isolate was inoculated into a defined chemical medium containing primarily carbohydrates and was incubated aerobically at 37 degrees C for 1 h . After centrifugation, the supernatants were placed on ice to stop further enzymatic reactions . Specimens were injected into an Aminex HPX-87H column in order to determine carbohydrates and acid metabolic products . Peak areas of carbohydrates for each isolate were compared with those for uninoculated medium . As the utilization indexes of raffinose, lactose and arabinose were found to be particularly significant, the patterns of carbohydrate utilization could be used for the identification of Bacteroides species . This method can be adapted for diagnostic laboratory use and has good potential for automated microbial identification.

Showa Shigakkai Zasshi, 1988 Dec, 8(4), 405 - 12
Purification and characterization of intracellular dextranase of Bacteroides oralis Ig4a; Igarashi T et al.; Multiple forms of dextranase were detected in both intra- and extracellular fractions of Bacteroides oralis Ig4a . The molecular weights of these enzymes varied from 52,000 to 260,000 by sodium dodecyl sulfate-polyacrylamide-blue dextran gel electrophoresis . The intracellular dextranases were fractionated by chromatography and gel filtration steps, and the dextranases IV and V were obtained . The former was only partially pure . The molecular weights of the dextranases IV and V were estimated to be 120,000 and 105,000, respectively, by SDS-PAGE . The dextranase V was further characterized and it was revealed that the pH- and temperature optima were 5.0, and 55 degrees C, respectively . The Km value was 6.7 x 10(-2) mM for dextran T-70 . The enzyme did not exhibit any metal ion requirements, but was inhibited by CoCl2 and HgCl2; lysine and alanine contents were especially high; it hydrolyzed the alpha-1,6-glucan by an exo-type mechanism, and was inactive toward glucans containing alpha-1,3-, alpha-1,4-, and beta-1,4-linkages.

Nippon Shishubyo Gakkai Kaishi, 1988 Dec, 30(4), 1156 - 67
{Microbiological evaluation of topical application of the controlled release strips containing ofloxacin (PT-01) in the human periodontal pocket}; Kimura S et al.; The recognition that destructive periodontal diseases may be caused by specific microorganisms has led to an increased interest and usage of antimicrobial agents in periodontal therapy . In this study, the effect of topical application of ofloxacin (OFLX), a synthetic antibiotic, was microbiologically evaluated . The new developed controlled release strips containing OFLX (PT-01), in which there were structurally immediate- and sustained-releasing portions, were applied to the periodontal pockets of 27 adult subjects with periodontitis . Three different sites with a deep probing pocket depth (greater than or equal to 5 mm) were randomly selected in each patient, and were divided into three groups, i.e., PT-01 applied site (T), placebo-applied site (P) and control site (C) . Periodontal treatments consisted of oral hygiene instruction and supragingival scaling on day 0 and 7, and subgingival scaling and root planing on day 14 . PT-01 was weekly applied on day 0 to 35, and the subgingival plaque samples from each site were collected on day 0, 14, 21 and 42 . The dynamics of subgingival microflora was investigated by dark field microscopy for determination of the %s of spirochetes, motile rods and coccoid cells, and anaerobic and aerobic cultivations for the determinations of the total number of subgingival bacteria, black-pigmented Bacteroides (BPB), Fusobacterium species and Actinobacillus actinomycetemcomitans . The results showed that the significant reduction of %s of spirochetes and motile rods and significant increase of % coccoid cells were found in only PT-01 applied sites during first 14 days . In this period, the total number of cultivable bacteria, BPB and Fusobacterium species were also significantly reduced in T sites . While, after subgingival scaling and root planing were performed, significant changes in the proportions and numbers of the subgingival microflora were found in all sites . Especially, PT-01 applied site showed significant improvement in the %s of spirochetes and motile rods as well as the total number of the bacteria . Moreover, the further microbiological determinations of the each isolate revealed that no detectable amounts of A . actinomycetemcomitans could be found from any samples in this study . These results suggested that weekly application of PT-01 in the periodontal pocket could have significant effects on the qualitative and quantitative improvements in the subgingival microflora . It was also suggested that the application of PT-01 might have ameliorating effect as adjuncts of mechanical subgingival plaque control in the periodontal treatment.

Antimicrob Agents Chemother, 1988 Dec, 32(12), 1848 - 53
Mechanism of action of cephalosporins and resistance caused by decreased affinity for penicillin-binding proteins in Bacteroides fragilis; Yotsuji A et al.; The susceptibilities of 52 clinical isolates of Bacteroides fragilis to five monoanionic cephalosporins were examined . Cefoperazone showed the highest antibacterial activity, followed by ceftezole, cefazolin, cefamandole, and cephalothin . There were two groups of resistant strains: one group (ca . 15%), of which B . fragilis G-232 was a typical sample, was resistant to ceftezole (MIC, 100 micrograms/ml), cefazolin (MIC, 100 micrograms/ml), and cephalothin (MIC, 200 micrograms/ml) but not cefoperazone (MIC, 6.25 micrograms/ml) or cefamandole (MIC, 25 micrograms/ml) . On the basis of studies of stability to beta-lactamase, outer membrane permeation, and affinity for penicillin-binding proteins (PBPs), we conclude that decreased affinity for PBP 3 may play an important role in the resistance to ceftezole, cefazolin, and cephalothin in B . fragilis G-232 . Another group (also ca . 15%), of which B . fragilis G-242 was a representative, was resistant to all five cephalosporins (MIC, 100 to 400 micrograms/ml) and produced a high amount of beta-lactamase . Similar broad-spectrum resistance was seen in a mutant of strain G-232 that had a greater-than-30-fold increase in beta-lactamase production.

J Antimicrob Chemother, 1988 Dec, 22(6), 785 - 90
Permeability to beta-lactams in Bacteroides fragilis; Cuchural GJ et al.; Bacteroides fragilis strains TAL2480 and TAL3636 were used to assess outer membrane permeability to various beta-lactam compounds . These strains were chosen because they possess beta-lactamases capable of hydrolysing all commonly employed beta-lactams except monobactams . The beta-lactamases are located in the periplasmic space and could be released by sonication and osmotic shock . Permeability was calculated by the method of Zimmerman & Rosselet (1977, Antimicrobial Agents and Chemotherapy 12, 368-72) . The rank order of permeative ability (from fastest to slowest) was as follows: cephaloridine, imipenem, cefotaxime, cefoxitin, cefoperazone, nitrocefin, cephalothin, and latamoxef . Our results showed that ionic charge, hydrophobicity, and molecular weight influenced beta-lactam drug uptake by B . fragilis . These results are similar to findings for Escherichia coli, where increased negative charge and increased molecular weight are associated with decreased drug uptake . However, unlike E . coli, increased drug hydrophobicity, for a given charge and molecular weight of the drug, was associated with increased uptake by B . fragilis.

Antimicrob Agents Chemother, 1988 Dec, 32(12), 1825 - 9
Comparative pharmacokinetics and serum inhibitory activity of clindamycin in different dosing regimens; Flaherty JF et al.; The comparative pharmacokinetics and serum inhibitory effects of clindamycin were evaluated in six healthy male subjects given multiple-dose infusions of the following regimens in a crossover fashion: 600 mg every 6 h, 900 mg every 8 h, and 1,200 mg every 12 h . Serial blood samples were obtained after the last dose in each regimen and analyzed for clindamycin by a sensitive and specific high-performance liquid chromatography assay technique . Clindamycin pharmacokinetics were estimated by using noncompartmental methods, and serum inhibitory titers were serially determined against Bacteroides fragilis ATCC 25285 and evaluated by using area under the serum inhibitory curve (AUIC) . Maximum and minimum concentrations in plasma averaged 12.2 +/- 1.6 and 1.2 +/- 0.6, 16.3 +/- 4.0 and 0.9 +/- 0.5, and 16.8 +/- 2.5 and 0.4 +/- 0.2 micrograms/ml for the 600-, 900-, and 1,200-mg regimens, respectively . Clindamycin plasma clearance and elimination half-life averaged 23.3 +/- 4.0 liters/h and 1.9 +/- 0.4 h for the 600-mg regimen, 25.6 +/- 8.2 liters/h and 2.1 +/- 0.4 h for the 900-mg regimen, and 26.4 +/- 4.7 liters/h and 2.1 +/- 0.4 h for the 1,200-mg regimen . These results were not significantly different . Apparent volume of distribution increased significantly for the 1,200-mg regimen compared with the 600-mg regimen . Mean maximum reciprocal serum inhibitory titers were 96 +/- 35, 101 +/- 43, and 160 +/- 78 for the 600-, 900-, and 1,200-mg regimens, respectively . Minimum reciprocal serum inhibitory titers averaged 12 +/- 4, 6 +/- 3, and 5 +/- 2 for the low-, medium-, and high-dose regimens, respectively . Mean AUIC increased roughly in proportion to dose . Similar daily values for the area under the concentration-time curve and for AUIC for each of the regimens suggest similar daily drug exposure and serum inhibitory activity . A regimen of 1,200 mg every 12 h may represent an alternative dosing strategy for clindamycin.

Br J Oral Maxillofac Surg, 1988 Dec, 26(6), 452 - 7
The microbiology and management of acute dentoalveolar abscess: views of British oral and maxillofacial surgeons; Gill Y et al.; Improvements in microbiological technology have established a major role for anaerobes including Gram-positive anaerobes such as peptococci and peptostreptococci and Gram-negative anaerobes such as bacteroides and fusobacteria species in acute dentoalveolar abscesses . Organisms isolated increasingly may be, or may become, resistant to penicillin or erythromycin but metronidazole appears effective against many . These facts have implications for treatment when antimicrobials are indicated . This study presents the current views of British oral and maxillofacial surgeons responding to a questionnaire as to the causative microorganisms, selection of antimicrobial and route of administration and relates these to the current scientific basis for therapy.

Appl Environ Microbiol, 1988 Dec, 54(12), 3019 - 22
Effect of phenolic monomers on the growth and beta-glucosidase activity of Bacteroides ruminicola and on the carboxymethylcellulase, beta-glucosidase, and xylanase activities of Bacteroides succinogenes; Martin SA et al.; trans-p-Coumaric acid inhibited the growth of Bacteroides ruminicola on both cellobiose and glucose, while trans-ferulic acid and vanillin retarded growth . The phenolic monomers varied in their potential to inhibit the Bacteroides succinogenes beta-glucosidase, carboxymethylcellulase, and xylanase, with p-coumaric acid being the most inhibitory . The B . ruminicola beta-glucosidase was inhibited less than 10% by all three compounds.

Nippon Shishubyo Gakkai Kaishi, 1988 Dec, 30(4), 1061 - 9
{The inhibitory effects of chicken ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis culture supernatant, human PMN and human gingival crevicular fluid}; Kudo K et al.; We examined in vitro the inhibitory effects of ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis (B . gingivalis) culture supernatant, in human peripheral blood polymorphonuclear leucocytes (PMN), and in gingival crevicular fluid (GCF) from periodontitis patients . Measurement of collagenolytic activity was conducted with a CollagenoKit CLN-100 using FITC-conjugated type I collagen . The FITC-conjugated collagen was reacted with the sample in solution, and the residue was selectively degenerated at 35 degrees C and removed with ethanol . The fluorescence of the removed residue was then measured . The collagenolytic activity from B . gingivalis displayed dose dependent inhibition as high as 81.4% following addition of ovomacroglobulin at 224 micrograms/ml . The collagenolytic activity from human peripheral blood PMN showed, as a result of addition of 1,600 micrograms/ml of ovomacroglobulin, inhibition as high as 62.4% . The collagenolytic activity from human GCF, which was obtained from patients with different degrees of periodontal disease, exhibited as high as 71.0% inhibition after addition of 1,600 micrograms/ml ovomacroglobulin . Ovomacroglobulin showed almost the same level of inhibition obtained from alpha 2-macroglobulin, which was measured as a positive control . It was also recognized by SDS-PAGE that collagenolytic activity was inhibited after preincubation with added ovomacroglobulin . This collagenolytic activity, which dissolved the collagen substrate, was derived from B . gingivalis and human GCF . The above results demonstrate that ovomacroglobulin inhibits collagenolytic activity from B . gingivalis, human PMN, and human GCF.

Antimicrob Agents Chemother, 1988 Dec, 32(12), 1830 - 3
Comparative efficacies of amoxicillin-clavulanic acid and ampicillin-sulbactam against experimental Bacteroides fragilis-Escherichia coli mixed infections; Gisby J et al.; Amoxicillin-clavulanic acid was compared with ampicillin-sulbactam in preventing the development of mixed infections produced in mice by subcutaneous inoculation of amoxicillin-resistant strains of Bacteroides fragilis and Escherichia coli . At doses designed to produce concentrations in mouse plasma similar to those obtained in humans, both amoxicillin-clavulanic acid and ampicillin-sulbactam were effective in preventing an infection caused by B . fragilis VPI 8908 mixed with E . coli E96, both strains being susceptible in vitro to each combination . However, ampicillin-sulbactam failed to arrest the progression of infections involving a more potent beta-lactamase-producing strain, E . coli 41548, even when a comparatively low inoculum was tested . In contrast, amoxicillin-clavulanic acid therapy effectively reduced the bacterial numbers at the site of infection . These data illustrate the need to treat polymicrobial infections with agents effective against the responsible aerobic as well as anaerobic bacteria.

Antimicrob Agents Chemother, 1988 Dec, 32(12), 1797 - 800
The cryptic tetracycline resistance determinant on Tn4400 mediates tetracycline degradation as well as tetracycline efflux; Park BH et al.; Escherichia coli containing the cryptic tetracycline resistance determinant (class F) from the Bacteroides fragilis transposon Tn4400 on plasmid pGAT400 expressed a detoxification of tetracycline as well as an active efflux of tetracycline . This finding concurs with the report of detoxification for a related tetracycline resistance determinant from B . fragilis on Tn4351 (B . S . Speer and A . Salyers, J . Bacteriol . 170:1423-1429, 1987), which specifies a 10-fold-higher resistance than Tn4400 . Inactivation of tetracycline occurred at an initial rate of congruent to 0.7 micrograms of tetracycline per h per 10(8) cells, as determined by biologic assay and chromatographic analysis . The detoxification is a chemical degradation which can occur in the absence of energy-dependent efflux . The products of this degradation were not substrates for active transport into susceptible cells or out of pGAT400-containing E . coli . These results indicate that Tn4400 mediates two functionally different mechanisms for tetracycline resistance: an active efflux of tetracycline and a degradation of tetracycline.

J Clin Microbiol, 1988 Nov, 26(11), 2361 - 6
Annual incidence, epidemiology, and comparative in vitro susceptibilities to cefoxitin, cefotetan, cefmetazole, and ceftizoxime of recent community-acquired isolates of the Bacteroides fragilis group; Goldstein EJ et al.; The six species of the Bacteroides fragilis group are potent pathogens and commonly have different susceptibility patterns . We determined the relative annual isolation rate of anaerobic bacteria and the susceptibility of B . fragilis group species isolated during 1987 at two community hospitals . The relative frequencies of isolation of 261 strains were as follows: B . fragilis, 61%; B . thetaiotaomicron, 17%; B . distasonis, 7%; B . vulgatus, 6%; B . ovatus, 5%; and B . uniformis, 4% . A total of 234 recent clinical isolates were tested against cefmetazole, cefotetan, cefoxitin, ceftizoxime, clindamycin, imipenem, and piperacillin by a brucella agar dilution method . Imipenem was the most active agent tested with all but three isolates (two B . vulgatus and one B . distasonis) susceptible to less than 2 micrograms/ml . Of the cephalosporins tested, cefoxitin, cefotetan, and cefmetazole were relatively equal against B . fragilis, with 93 to 98% of strains susceptible to 32 micrograms/ml . Ceftizoxime was less active, with an MIC for 90% of strains tested of 128 micrograms/ml and only 75% of isolates susceptible to 32 micrograms/ml . Against B . ovatus, B . vulgatus, B . thetaiotaomicron, and B . uniformis, cefoxitin showed a two- to threefold-superior activity compared with that of cefotetan and cefmetazole . In general, ceftizoxime was much less active, except against B . distasonis, for which 78% of isolates were susceptible to 32 micrograms/ml compared with 68% for cefoxitin, 19% for cefmetazole, and 16% for cefotetan . Clindamycin and piperacillin showed activity similar to that of cefoxitin, except piperacillin was less active versus B . vulgatus and B . distasonis . We therefore suggest that clinical laboratories determine the species of B . fragilis group isolates as well as perform susceptibility studies on the isolates . Clinicians should be aware that while B . fragilis is the most frequent isolate, 38% of isolates are from other, more resistant B . fragilis group species.

J Gen Microbiol, 1988 Nov, 134 ( Pt 11), 2867 - 76
Serological properties and immunobiological activities of lipopolysaccharides from black-pigmented and related oral Bacteroides species; Fujiwara T et al.; Lipopolysaccharides (LPS) from five species of oral Bacteroides, B . gingivalis strains 381 and ATCC 33277, B . oralis ATCC 33269, B . loescheii ATCC 15930, B . intermedius ATCC 25611 and B . corporis ATCC 33547, were extracted from whole cells by the phenol/water procedure, and subsequently purified by treatment with nuclease and ultracentrifugation . The LPS were composed of hexoses, glucosamine, fatty acids and phosphorus . Heptose and 2-keto-3-deoxyoctonate were not detected . The LPS preparations from B . gingivalis strains 381 and ATCC 33277 presented very similar SDS-polyacrylamide gel electrophoresis patterns when stained with ammoniacal silver . They produced a fused precipitin band against an antiserum to B . gingivalis 381 LPS in immunodiffusion tests . Antisera raised against the LPS from B . loescheii and B . intermedius reacted with the LPS prepared from all the oral Bacteroides strains except those of B . gingivalis . All the LPS preparations were mitogenic for spleen cells of BALB/c (nu/nu) mice, but not for thymus cells from C3H/HeN mice . The LPS induced marked mitogenic responses and polyclonal B cell activation for spleen cells of not only C3H/HeN (LPS responder) mice, but also C3H/HeJ (LPS nonresponder) mice . The mitogenic responses were not suppressed significantly upon addition of polymyxin B to the reaction mixture . These LPS also enhanced interleukin-1 production by murine peritoneal macrophages and mouse cell line J744 . 1 macrophages . Hydrolysis of B . gingivalis ATCC 33277 LPS in 1 m-HCl at 100 degrees C for 1 h yielded lipid and polysaccharide . The lipid portion was largely composed of fatty acids and glucosamine, and was mitogenic for spleen cells from C3H/HeJ as well as C3H/HeN mice, while the polysaccharide portion induced no significant mitogenic responses under similar experimental conditions.

Appl Environ Microbiol, 1988 Nov, 54(11), 2672 - 6
Cloning and expression of a Bacteroides succinogenes mixed-linkage beta-glucanase (1,3-1,4-beta-D-glucan 4-glucanohydrolase) gene in Escherichia coli; Irvin JE et al.; A pseudorandom genomic library of Bacteroides succinogenes DNA, cloned into pUC8 in Escherichia coli, was screened for beta-glucanase activity on 0.1% lichenan plates . Six high-activity clones, containing identical 5.2-kilobase inserts of B . succinogenes DNA, were obtained . The clones exhibited activity solely on beta-glucan substrates containing beta-(1----3)(1----4) linkages, thus manifesting a specific fibrolytic enzyme previously unrecognized in B . succinogenes . A subclone (pJI10) of the original insert (1.35 kilobases in size) expressed full beta-glucanase activity under control of its own promoter . The expression of beta-glucanase in pJI10 appeared subject to catabolite regulation by glucose . Detailed analysis of enzyme activity in the parental and deleted derivatives, subcloned into pUC18 and pUC19, suggested that the apparent glucose repression was an artifact arising as a consequence of interactions with the lac transcriptional unit in the plasmid vector.

Vet Clin North Am Small Anim Pract, 1988 Nov, 18(6), 1167 - 82
Management of anaerobic infections; Dow SW; Successful management of anaerobic infection first requires an accurate diagnosis . Cytologic examination of wound exudates and inspection for characteristic clinical clues greatly facilitates an accurate initial diagnosis of anaerobic infection . Knowledge of antimicrobial activity against specific anaerobic pathogens is essential, since antibiotic susceptibility information is not routinely available . Whenever possible, antimicrobial and surgical therapy should be combined in managing anaerobic infections . Chloramphenicol, clindamycin, and metronidazole provide the most consistently reliable activity against pathogenic anaerobes, including Bacteroides . Penicillins are also generally effective, except for treatment of infections caused by penicillinase-producing strains of Bacteroides . Cephalosporins are not considered drugs of choice for anaerobic infections, although cefoxitin may in some instances be useful as monotherapy of mixed infections containing obligate anaerobes and coliform bacteria . Aminoglycosides and sulfonamides are ineffective and should be avoided for treatment of anaerobic infection.

Can J Microbiol, 1988 Nov, 34(11), 1189 - 95
The Bacteroides glycocalyx as visualized by differential interference contrast microscopy; Lambe DW Jr et al.; The glycocalyx of eight strains representing six species of Bacteroides was examined by differential interference contrast microscopy . Wet mounts in India ink were prepared from bacteria cultured in broth and on an agar medium; the wet mounts were observed by phase-contrast microscopy and differential interference contrast microscopy . With differential interference contrast microscopy, all bacteria demonstrated a glycocalyx, which included capsules surrounding single cells and microcolonies, strands of glycocalyx connecting cells and microcolonies, detached slime, and solid masses of glycocalyx in which innumerable bacteria were enmeshed . Bacteria showed comparable amounts of glycocalyx by visual observation with differential interference contrast microscopy whether grown on plates or in broth . Serial transfers of cultures did not diminish the amount of glycocalyx . Differential interference contrast microscopy proved to be a superior method to phase contrast for examining wet preparations of Bacteroides.

Anal Biochem, 1988 Oct, 174(1), 204 - 8
Detection of cellulose-binding proteins in electrophoresis gels by filter paper affinity blotting; Montgomery L et al.; Proteins separated in electrophoresis gels were tested for the ability to bind cellulose by a simple blotting procedure . Proteins were blotted onto Whatman No . 1 filter paper by diffusion or by electrophoretic transfer and detected by Coomassie blue staining . Certain proteins released into culture supernatant by Bacteroides succinogenes NR9 (ATCC 43854) adhered strongly to cellulose, but were not found to have carboxymethylcellulose activity . Boiling of samples prior to electrophoresis eliminated the ability of proteins to bind to cellulose . Proteins that did not adhere to filter paper cellulose were detected on a nitrocellulose membrane placed behind the filter paper during electrophoretic transfer . The technique, referred to as filter paper affinity blotting, detects cellulose-binding proteins with great sensitivity.

Ann Ophthalmol, 1988 Oct, 20(10), 397 - 9
Presence of anaerobic bacteria in conjunctivitis associated with wearing contact lenses; Brook I; Ten anaerobic bacterial species were found in conjunctival cultures obtained from six patients who wore contact lenses and developed conjunctivitis . In three instances the anaerobic bacteria were associated with facultative bacteria . The predominant anaerobic isolates were Peptostreptococcus species (three isolates), Bacteroides sp . (two), and Fusobacterium sp . (two) . It was the practice of five of the six patients to wet their lenses with saliva . It is recommended that a culture for anaerobes be obtained from any patient who uses contact lenses and develops conjunctivitis.

Br J Exp Pathol, 1988 Oct, 69(5), 631 - 8
The effect of a toxin from Bacteroides ureolyticus on the mucosal epithelium of human and bovine oviducts; Fontaine EA et al.; Bacteria-free filtrates of nine strains of Bacteroides ureolyticus, most of which had been isolated from the urethra of men with non-gonococcal urethritis, damaged the mucosal epithelium of human fallopian tube and bovine oviduct organ cultures . The damage, pronounced after three days, was manifested by loss of ciliary activity . Histological observations, supported by scanning electron microscopy, showed that this loss was due to disruption of the epithelia with sloughing of cells . It is likely that the inhibitory activity of the filtrates was due to endotoxin since lipopolysaccharides extracted from the bacteria had a similar deleterious effect on oviduct mucosal epithelia . It is speculated that B . ureolyticus has the potential for causing damage to the urethral mucosa by the same mechanism.

J Clin Microbiol, 1988 Oct, 26(10), 2144 - 6
Evaluation of the KOH test and the antibiotic disk test in routine clinical anaerobic bacteriology; Bourgault AM et al.; We have evaluated the KOH test, the antibiotic disk identification test, and the Gram stain reaction for the preliminary grouping of gram-positive and gram-negative anaerobes and have assessed the value of erythromycin 60-micrograms-disk resistance as a predictive index of clindamycin resistance among anaerobes . By testing 931 clinical isolates, 281 gram positive and 650 gram negative, with the KOH test and vancomycin 5-micrograms-disk test, we obtained the following parameters: sensitivity, 89.7 and 97.1%; specificity, 97.5 and 98.3%; positive predictive value, 80.4 and 98.7%; and efficiency, 92.1 and 98% for the KOH test and the vancomycin test, respectively . The KOH reaction incorrectly grouped 42 of 97 Bacteroides bivius and 12 of 50 pigmented Bacteroides strains . The vancomycin test correctly identified 63 of 67 gram-negative strains that had given a negative KOH reaction . The erythromycin disk result correctly predicted clindamycin resistance in gram-negative isolates but had a sensitivity of 85.7%, a specificity of 92.4%, and a positive predictive value of 42.8% for gram-positive isolates . Therefore, the use of these preliminary identification tests can assist in the correct grouping of anaerobes and accurately predict significant clindamycin resistance in gram-negative anaerobic bacteria.

J Infect Dis, 1988 Oct, 158(4), 766 - 72
Prevention of intra-abdominal abscesses by fibrinolysis using recombinant tissue plasminogen activator; Rotstein OD et al.; We studied whether intraperitoneal fibrinolysis using recombinant tissue plasminogen activator (t-PA) could prevent abscess formation in the rat model of intra-abdominal infection caused by fibrin clots . Single-dose administration of t-PA at concentrations greater than 0.005 mg/mL at surgery or delivered by open lavage within 1 h of surgery completely obviated abscess formation induced by Bacteroides fragilis-infected clots without altering mortality (approximately 0.6%) . With mixed Escherichia coli-B . fragilis clots, t-PA increased the mortality rate from the control level of 43.8% to 81.3% but prevented abscesses in survivors . This increased mortality rate was probably due to an acute E . coli bacteremia . Antibiotics plus t-PA prevented both mortality and abscess formation . Intraperitoneal fibrinolysis may be a useful adjunct to antibiotics and appropriate surgery in the management of intra-abdominal infection.

Antimicrob Agents Chemother, 1988 Oct, 32(10), 1511 - 4
Comparison of antibiotic activities by using serum bactericidal activity over time; Guglielmo BJ et al.; In evaluating antimicrobial agents with similar spectra of activity, it is difficult to determine equivalent dosage regimens . In vitro potency, pharmacokinetic disposition, and other factors determine the usual dosing regimen . Knowledge of the serum bactericidal activity over time may assist in defining the potency of comparative antimicrobial agents . Cefoxitin and ceftizoxime, cephalosporins with gram-negative aerobic and anaerobic activity, have been promoted as monotherapy in the treatment of intra-abdominal infection . In a randomized, crossover study, six healthy volunteers received single 30-mg/kg doses of cefoxitin and ceftizoxime . Greater serum activity against Escherichia coli and Bacteroides fragilis was observed with ceftizoxime than with cefoxitin . The results suggest that ceftizoxime can be administered in a lower daily dosage than cefoxitin . We propose that the present study may serve as a prototype for future studies attempting to assess equivalent dosing regimens for antibiotics with similar spectra of activity.

J Gen Microbiol, 1988 Oct, 134 ( Pt 10), 2713 - 20
Detection of fimbriae and fimbrial antigens on the oral anaerobe Bacteroides gingivalis by negative staining and serological methods; Suzuki Y et al.; We screened 63 clinical isolates of Bacteroides gingivalis from eight different laboratories for the presence of fimbriae by negative staining and by immunological methods . Techniques used were bacterial agglutination, Ouchterlony immunodiffusion and Western immunoblotting analysis using rabbit anti-fimbriae and anti-fimbrilin sera raised against fimbriae and fimbrilin (a constituent protein of B . gingivalis fimbriae) from B . gingivalis strain 381 . In 49 of the 51 strains tested, fimbriae were clearly detected by negative staining, and 30 (60%) of the fimbriate strains were positive in all three of the immunological assays . A total of 37 strains (75%) were positive by immunoblotting analysis, which was the most reliable of the serological methods used in this study . The study shows that the majority of B . gingivalis strains are fimbriate, and that these fimbriae are immunologically related to the fimbriae of B . gingivalis strain 381 . Molecular heterogeneity of fimbrilin was discovered by the immunoblotting analysis, when different strains were compared . With most of the strains, including strain 381, the antifimbrilin serum reacted with a protein of apparent molecular mass 43 kDa, but with 15 strains the immuno-reactive protein had an apparent molecular mass of 46 kDa.

J Dent Res, 1988 Oct, 67(10), 1267 - 70
The use of whole-cell DNA probes for the identification of Bacteroides intermedius isolates in a dot blot assay; Moncla BJ et al.; Bacteroides intermedius includes two distinct groups of organisms that are phenotypically indistinguishable by conventional methods . These two groups are represented by the type strain of the species ATCC 25611T (B . intermedius type I) and by ATCC 33563 (B . intermedius type II) . Members of each group can be distinguished from each other by analysis of the cellular protein composition by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and by DNA-DNA homology studies, because they share less than 40% homology . The purpose of this study was to prepare specific DNA probes for the two groups of Bacteroides intermedius and to test them against field isolates . Whole-cell DNA probes were prepared from B . intermedius types I and II and tested against 253 field strains of Bacteroides which had been identified by conventional phenotypic tests as B . intermedius . Of these, 170 (67%) hybridized with the B . intermedius type I DNA probe, 28 (11%) with the type II, and 23 (9%) failed to react with the B . intermedius probes but did hybridize with either B . melaninogenicus, B . loescheii, or B . corporis whole-cell DNA probes . The 32 (13%) remaining isolates failed to hybridize with any of the five Bacteroides probes or with probes to B . asaccharolyticus, B . buccae, B . buccalis, B . denticola, B . gingivalis, B . oralis, or B . oris . These data demonstrate the usefulness of whole-cell DNA probes for the identification of phenotypically similar or identical field isolates.

Surg Gynecol Obstet, 1988 Sep, 167(3), 175 - 9
Emergence of antibiotic resistant strains of Bacteroides fragilis; Scher KS; From 1981 to 1986, antibiotic susceptibility was tested by the agar dilution method in 534 isolates of Bacteroides fragilis organisms recovered from clinical specimens . Drugs evaluated included penicillin, ampicillin, tetracycline, clindamycin, metronidazole and chloramphenicol . Based on in vitro testing, tetracycline, ampicillin and penicillin were ineffective against B . fragilis because of high rates of resistance to these agents (74 per cent tetracycline resistant, 80 per cent ampicillin resistant and 89 per cent penicillin resistant) . Throughout the five years of the study, 5.1 per cent of the organisms studied were resistant to clindamycin compared with 2.1 per cent resistant to metronidazole (p less than 0.01) and 0.9 per cent resistant to chloramphenicol (p less than 0.001) . More important than the relative resistance rates to the various antibiotics is the observation that this is a dynamic process that is influenced by local practices of administering antibiotics . In 1981, the first year of the survey, no clindamycin resistant B . fragilis isolates were identified; by 1986, 7.8 per cent of the strains proved resistant to this antibiotic . Similarly, no metronidazole or chloramphenicol resistant organisms were demonstrated in 1981 or 1982; thereafter, resistance to these two drugs was noted with increasing frequency each year . The emergence of B . fragilis strains that are resistant to the antibiotics in current use mandates the surveillance of the local susceptibility data to identify important trends . When increasing rates of resistance are noted to one antibiotic, alternative regimens can be used.

Infect Immun, 1988 Sep, 56(9), 2392 - 9
Natural occurrence of black-pigmented Bacteroides species in the gingival crevice of the squirrel monkey; Clark WB et al.; The objective of this study was to determine whether the squirrel monkey (Saimiri scuireus) is indigenously colonized with black-pigmented bacteroides (BPB) resembling human Bacteroides gingivalis and Bacteroides intermedius (suspected periodontal pathogens) and to determine the usefulness of the squirrel monkey as an in vivo model for studying colonization by putative pathogens . We assayed the subgingival plaques of 138 monkeys of various ages and in four different colonies for the presence of anaerobic BPB microorganisms . We also tested half the animals for the presence of Actinobacillus actinomycetemcomitans . Clinical indices and levels of serum antibody to B . gingivalis were recorded . We detected BPB in 50% of the animals and A . actinomycetemcomitans in 69% of the animals . The presence of BPB was generally associated with increased age, increased gingival index, presence of calculus, and increased levels of serum antibody . These data indicate that the squirrel monkey may be a good model for studying the parameters of natural infection of the gingival crevice with suspected periodontopathogenic BPB microorganisms.

Eur J Epidemiol, 1988 Sep, 4(3), 360 - 5
Belgian Collaborative Study of the in-vitro susceptibility of the Bacteroides fragilis group . A Belgian Collaborative Study Group; Isolation of colonial variants of Bacteroides gingivalis W50 with a reduced virulence; Pathology Division, PHLS Centre for Applied Microbiology and Research, Salisbury, WiltshireThe spontaneous appearance of unusual colony forms was observed during prolonged growth of Bacteroides gingivalis W50 in a chemostat . Two variants were selected for further study which could be distinguished from the parent strain by the rate and intensity of pigmentation of their colonies . For example, after anaerobic incubation for 14 days, variant W50/BR1 produced brown colonies whereas those of the parent strain were black; in contrast, variant W50/BE1 did not show signs of pigmentation until incubation had continued for 21 days . In subsequent studies in the chemostat, variant W50/BE1 bred true even after prolonged growth whereas other colony forms appeared after incubation of variant W50/BR1 for 14 days . The relatedness of W50/BR1 and W50/BE1 to the parent strain was confirmed by comparisons of the whole-cell fatty-acid profiles, the patterns of pre-formed enzymes and by the metabolic end products after growth . However, the variants did differ from the parent strain in their virulence in a mouse pathogenicity model . The parent strain killed all mice given infective doses greater than 5 x 10(8) cfu whereas W50/BR1 was much less virulent (2 out of 10 mice killed and higher infective doses needed for higher mortality rates) and W50/BE1 was avirulent at all infective doses tested.

J Dent Res, 1988 Sep, 67(9), 1196 - 9
Relationship between enzyme activities involved in oxygen metabolism and oxygen tolerance in black-pigmented Bacteroides; Amano A et al.; In this study, the relationship between enzyme activities involved in oxygen metabolism and the degrees of oxygen tolerance in black-pigmented Bacteroides was investigated . All strains of Bacteroides tested possessed the activities of NADH oxidase and superoxide dismutase, whereas the activities of catalase and peroxidases were not detected in the cell-free extracts . There were relatively high correlations between oxygen tolerance and activity of either NADH oxidase or superoxide dismutase . The activity of superoxide dismutase showed a higher correlation with oxygen tolerance than with that of NADH oxidase . Among the species tested, Bacteroides gingivalis showed the highest activities of both the enzymes and was the most tolerant in the presence of oxygen . Furthermore, the activities of these two enzymes increased during aeration of the oxygen-tolerant strain Bacteroides gingivalis 381, but not in the oxygen-sensitive strain Bacteroides denticola ATCC 33185 . These results suggest that superoxide dismutase and NADH oxidase might be important for protection of black-pigmented Bacteroides against the toxic effect of oxygen.

J Dairy Sci, 1988 Sep, 71(9), 2416 - 27
Proteolysis of alcohol-treated soybean meal proteins by Bacteroides ruminicola, Bacteroides amylophilus, pepsin, trypsin, and in the rumen of steers; Lynch GL et al.; Sodium dodecyl sulfate-gel electrophoresis and cation exchange chromatography were used to examine degradation of treated and untreated soybean meal protein fractions by Bacteroides amylophilus H18(1), Bacteroides ruminicola B(1)4, pepsin, trypsin, and intraruminally . Soybean meal treatments consisted of 30% vol/vol isopropanol, 40% propanol, or 50% ethanol at 22 degrees C or 70% ethanol at 80 degrees C . Water-soluble protein fractions were applied to a hydroxylapatite column and eluted with a discontinuous phosphate gradient of .03 to .27 and then .27 to 1.0 M . The four protein fractions with the highest absorbance at 276 nm were dialyzed against distilled water prior to being subjected to enzymatic hydrolysis . Soybean meal treated with 40% propanol had the greatest reduction in absorbance of all effluents at 275 nm, followed by soybean meal treated with 50% ethanol or 30% isopropanol . Comparison of electrophoretic patterns over time showed that B . amylophilus H18(1), degraded protein subunits more rapidly than B . ruminicola B(1)4 . Protein subunits with the highest molecular weights were the most rapidly degraded by B . amylophilus H18(1), B . ruminicola B(1)4, pepsin, and trypsin . Hydroxylapatite chromatography of omasal fluid from steers supplemented with untreated soybean meal or soybean meal treated with 70% ethanol at 80 degrees C indicated that no detectable soluble glycinin or conglycinin escaped ruminal degradation.

Infect Immun, 1988 Sep, 56(9), 2369 - 72
Use of lymphokines in treatment of experimental intra-abdominal abscess caused by Bacteroides fragilis; Gollapudi SV et al.; The role of cell-free soluble factors (lymphokines) derived from mitogen-activated splenic cells of mice previously immunized against Bacteroides fragilis was evaluated in the treatment of B . fragilis intra-abdominal abscess (IAA) . Neither clindamycin nor lymphokines alone were effective against an established B . fragilis IAA, but the combination of clindamycin and lymphokines decreased the abscess size and bacterial counts in the majority of animals . This suggests that the synergy of lymphokines with clindamycin effects cure of IAA caused by B . fragilis and that lymphokines might have an application as adjuncts to conventional antimicrobial therapy in this setting.

J Ultrastruct Mol Struct Res, 1988 Sep, 100(3), 263 - 8
Intracellular crystal formation in Bacteroides nodosus; Hine PM; An intracellular crystalline structure was found in at least two strains of Bacteroides nodosus . The inclusion appeared to be associated with good growth of the organism under optimum conditions following selective passage of rough colonies containing highly fimbriate cells . Several morphological forms of the inclusion were noted . Indiscriminate subculture of crystal-forming cultures led to the loss of this particular property indicating a genetically controlled system of either bacterial or bacteriophage origin.

Antimicrob Agents Chemother, 1988 Sep, 32(9), 1437 - 8
Emergence of fluoroquinolone resistance in Bacteroides fragilis accompanied by resistance to beta-lactam antibiotics; Kato N et al.; The in vitro susceptibilities of a group of 93 isolates of Bacteroides fragilis collected from 1983 to 1984 to six fluoroquinolones were compared with those of a group of 93 isolates collected from 1986 to 1987 . The recently collected strains were less susceptible than the older strains to all of the agents tested . Norfloxacin-resistant (MIC, greater than 100 micrograms/ml) strains were less susceptible to cefoxitin and piperacillin than norfloxacin-susceptible strains.

J Dent Res, 1988 Aug, 67(8), 1062 - 9
Relationships between periodontal health, salivary steroids, and Bacteroides intermedius in males, pregnant and non-pregnant women; Jonsson R et al.; Relationships between four steroids, determined by radio-immunoassay of whole saliva, and clinical and bacteriological parameters were studied in 90 subjects: males, menstruating females, and pregnant females . Pocket depths and both plaque and gingival bleeding scores were recorded . Total counts and percentages of Gram-negative organisms Bacteroides and B . intermedius were determined from anaerobic cultures of subgingival plaque from 9-14 subjects in each group . None of the clinical parameters for the pregnant females differed significantly from those of non-pregnant females, nor did these parameters show any significant correlation with progression of pregnancy . No correlations were detected between bacterial and clinical parameters in the pregnant group . There were no statistically significant differences between the total bacterial counts from the three groups, yet males had significantly higher proportions of Gram-negative bacteria, Bacteroides, and B . intermedius, than did pregnant and non-pregnant females . Proportions of B . intermedius did not differ significantly between the two female groups, nor was there any correlation with progression of pregnancy . While some steroids appeared to affect some clinical or bacteriological parameters in some groups, no obvious patterns consistent with different steroid levels were detected . The results do not indicate that increased hormone levels cause more severe periodontal disease in pregnant women, nor that high salivary steroid levels result in increased recovery of B . intermedius from subgingival plaque.

Can J Microbiol, 1988 Aug, 34(8), 938 - 46
Establishment of Bacteroides succinogenes and measurement of the main digestive parameters in the rumen of gnotoxenic lambs; Fonty G et al.; We attempted to determine the degree of diversification of the microflora that allow the establishment of Bacteroides succinogenes S85 in the rumen of gnotoxenic lambs . Four lambs (group I) received an inoculum orally, composed of 182 noncellulolytic bacterial strains (inoculum 1) previously isolated from the rumen of conventional young lambs . Two lambs (group II) were inoculated with 32 strains (inoculum 2) selected among the 182 strains of inoculum 1 . Two lambs (group III) received an inoculum (inoculum 3) composed of 106 noncellulolytic bacterial strains previously isolated from the rumen of meroxenic lambs . Two lambs (group IV) were inoculated with 16 strains (inoculum 4) chosen among the 106 strains of inoculum 3 . All lambs were inoculated from birth except two lambs of group I, which were inoculated from 1 month of age . Each lamb then received orally a pure culture of B . succinogenes . This strain became established more easily in the rumen of lambs that had received complex inocula (group I) . Its population reached a level close to that generally observed in conventional lambs (10(7)-10(8) bacteria.mL-1) . In contrast, B . succinogenes became established in only one lamb of group II, but bacterial numbers varied considerably . In group III, repeated inoculations were necessary to obtain its definitive establishment (10(7)-10(8) bacteria.mL-1 after weaning) . In spite of several inoculations, this cellulolytic species failed to establish in the rumen of lambs of group IV, which had received the less complex inoculum . The volatile fatty acid levels were very different from one lamb group to another . The more complex the inoculum administered to the animals, the higher the concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Environ Microbiol, 1988 Aug, 54(8), 1964 - 9
A deletion in the chromosome of Bacteroides thetaiotaomicron that abolishes production of chondroitinase II does not affect survival of the organism in gastrointestinal tracts of exgermfree mice; Salyers AA et al.; Bacteroides thetaiotaomicron, an obligate anaerobe normally found in high concentrations in the human colon, is one of the few colon bacteria that can ferment host mucopolysaccharides such as chondroitin sulfate . Previously, we found that a directed insertional mutation in the gene that codes for the chondroitinase II gene of B . thetaiotaomicron did not affect growth on chondroitin sulfate despite the fact that chondroitinase II accounts for 70% of the total cellular chondroitinase activity . Thus, the chondroitinase II gene did not seem to contribute significantly to growth on chondroitin sulfate when the bacteria were grown in laboratory medium . To determine whether this enzyme is important for bacteria growing in the intestinal tract, we tested the ability of a strain that does not produce chondroitinase II to colonize the intestinal tracts of germfree mice and to compete with wild-type B . thetaiotaomicron . The mutant used in these experiments carried a 0.5-kilobase deletion in the chondroitinase II gene and was constructed so that, unlike the original insertion mutant, it contained no exogenous DNA . The deletion mutant colonized the intestinal tracts of germfree mice at the same levels as the wild type . When a mixture of the deletion mutant and wild type was used to colonize germfree mice, the percent wild type, measured by colony hybridization with the deleted 0.5-kilobase fragment as the hybridization probe, did not rise to 100% even after periods as long as 9 weeks . In most experiments, the percent wild type did not rise significantly above the percent in the original mixture.(ABSTRACT TRUNCATED AT 250 WORDS)

J Gen Microbiol, 1988 Aug, 134 ( Pt 8), 2231 - 40
Characterization of proteases formed by Bacteroides fragilis; Gibson SA et al.; Bacteroides fragilis NCDO 2217 produced three major proteases, P1, P2 and P3 of estimated molecular masses 73, 52 and 34 kDa respectively . Protease P1 weakly hydrolysed azocasein but strongly hydrolysed valyl-alanine p-nitroanilide (VAPNA), glycyl-proline p-nitroanilide (GPRPNA), and to a lesser extent leucine p-nitroanilide (LPNA), indicating it to be an exopeptidase . Proteases P2 and P3 hydrolysed only azocasein and LPNA . The high protease:arylamidase ratios of these enzymes indicated that they were probably endopeptidases . Experiments with protease inhibitors suggested that P1 and P2 had characteristics of serine and metalloproteases respectively and that P3 was a cysteine protease . The proteolytic activity of whole cells was stimulated by divalent metal ions such as Mn2+, Ca2+ and Mg2+, but was strongly inhibited (about 95%) by Cu2+ and Zn2+ . The temperature optimum for protein hydrolysis was 43 degrees C . Proteolysis was temperature sensitive, however (90% reduction at 60 degrees C) and was maximal at alkaline pH, with two broad peaks at pH 7.9 and pH 8.8 . Cell fractionation showed that P1 was located intracellularly and in the periplasm, whereas P2 and P3 were largely associated with the outer membrane . Release of the membrane-bound proteases by treatment with 1 M-NaCl suggested that ionic interactions were involved in the association of these enzymes with the membranes.

J Clin Periodontol, 1988 Aug, 15(7), 453 - 63
Clinical and microbiological effects of root debridement in periodontal furcation pockets; Loos B et al.; The aim of the present study was to investigate longitudinally over 52 weeks the clinical and microbiological effects of plaque control and root debridement at molar furcation sites . The results were compared with changes at non-molar sites . 24 non-molar sites and 31 grade II molar furcation sites with probing depth greater than or equal to 5.0 mm were monitored in 11 patients . Clinical measurements consisted of plaque scores, probing depths, and changes in probing attachment level . Microbiological monitoring was carried out with phase-contrast microscopy and anaerobic culturing . The debridement resulted in improvement in probing measurements and microbiological counts for both groups of sites . A slightly less favorable clinical response was noted for molar furcation sites . Higher post-operative microbiological counts were found throughout the 52-week observation period for molar furcation sites . Sites with probing attachment loss showed higher microbial counts and higher proportions of spirochetes, black pigmented colony forming units (CFU), and Bacteroides gingivalis CFU than sites with probing attachment gain . Individual site analysis, however, demonstrated marked variations of the microbiological counts at the different postoperative time points . In the few available sites undergoing probing attachment loss, no apparent association between target micro-organisms and periodontal deterioration was observed.

Circ Shock, 1988 Aug, 25(4), 231 - 44
Chronic hyperdynamic sepsis in the rat: I . Characterization of the animal model; Mela-Riker L et al.; We describe a new rat model of chronic hyperdynamic sepsis . After control values for weight gain, and food and water intake of each animal were obtained over a 5-day period, male Sprague-Dawley rats weighing 370-425 g were anesthetized, catheterized to allow chronic cardiac-output measurements, and a sterile subcutaneous cavity was formed over the flank area . The animals were allowed a 3-4 day postoperative recovery period . Body weight, food and water intake, and cardiac output were measured daily . Frequent blood samples were withdrawn for bacterial cultures and white cell counts (WBC) . On the third and, in some cases, the fourth postoperative day, the subcutaneous cavity was inoculated with 10(9) colony-forming units of Escherichia coli and Bacteroides fragilis . The resulting sepsis was characterized by loss of body weight in spite of normal food and water intake, increased cardiac output, increased WBC, intermittent bacteremia, decreased muscle mass, and decreased cross-sectional area of skeletal muscle myofibrils . Two levels of septic response emerged--moderate and severe . Based on the above-mentioned measurements, it was possible to categorize all long-term septic animals into these two groups . Both groups exhibited cardiac-output, body-weight, and WBC data significantly different from sham controls . Repeated inoculations of the subcutaneous abscess initiated on the third postoperative day resulted in moderate sepsis with no long-term mortality, severe sepsis with 23% mortality over a 3-week period, or a 100% mortality within 4 days, depending on the virulence of the E . coli organisms used . The new model is ideally suited for pathophysiologic studies of sustained, hyperdynamic sepsis.

J Dent Res, 1988 Aug, 67(8), 1075 - 80
Attachment of Bacteroides gingivalis to collagenous substrata; Naito Y et al.; The ability of Bacteroides gingivalis 381 to attach to hydroxyapatite (HA) beads, treated with either human type I or type IV collagen, or to particles of bovine bone collagen was studied . All preparations were blocked with human albumin prior to being incubated with 3H-thymidine-labeled B . gingivalis 381 cells . The presence of collagen on HA surfaces (C-HA) significantly promoted attachment of the organism . HA treated with Type IV collagen bound B . gingivalis cells more effectively than did HA treated with type I collagen . Attachment of two additional strains of B . gingivalis to HA was also promoted by collagen . Binding to type I or type IV C-HA occurred rapidly, and equilibrium was attained within 45 min . B . gingivalis 381 cells also bound to particles of bovine bone collagen, and this appeared to be biphasic . Heating the bacteria abolished their ability to bind to C-HA . Attachment of B . gingivalis 381 cells to HA treated with type I collagen was strongly inhibited by the presence of soluble type I or type IV collagen, or gelatin, but not by the presence of human albumin, salivary proline-rich protein 1, or saliva . Human serum, fibronectin, fibrinogen, certain protease inhibitors, and some peptides were also inhibitory . 3H-fibronectin bound to bovine bone collagen particles and blocked the attachment of 14C-B . gingivalis cells . Mild trypsin treatment of the fibronectin-collagen complex restored its ability to promote 14C-B . gingivalis attachment concomitant with the loss of 3H-fibronectin . We suggest that elevated levels of proteases in the gingival sulcus, such as are associated with poor oral hygiene and gingivitis, might remove fibronectin and expose collagen molecules in the basement membrane, thereby promoting the attachment of B . gingivalis cells and facilitating their invasion into gingival tissues.

J Dent Res, 1988 Aug, 67(8), 1070 - 4
Correlations between gingival crevicular fluid enzymes and the subgingival microflora; Suido H et al.; Bacteroides gingivalis is a Gram-negative micro-organism implicated in the pathogenesis of adult periodontitis and producing relatively large amounts of specific enzymes . In the present study, subgingival samples taken from adults with moderate periodontitis were examined for the presence and relative amounts of enzymatic activity toward certain substrates . Enzyme levels were then correlated with clinical periodontal indices and microbiological analysis of subgingival plaque, including darkfield microscopy for bacterial morphotypes and immunofluorescence microscopy for B . gingivalis and Bacteroides intermedius . The results of this study indicate a significant positive correlation between levels of enzyme capable of degrading N-benzoyl-D,L-arginine-beta-naphthylamide hydrochloride, and subgingival B . gingivalis (r = 0.55) . There was a much lower correlation coefficient between this enzyme activity and subgingival B . intermedius (r = 0.26) . Statistically significant (p less than 0.01) positive correlations were also demonstrated between total bacterial cell counts and levels of enzymatic activity against N-benzoyl-D,L-arginine-beta-naphthylamide hydrochloride (r = 0.76), N-carbobenzoxy-glycyl-glycyl-L-arginine-beta-naphthylamide hydrochloride (r = 0.72), and glycyl-L-proline-4-methoxy-beta-naphthylamide hydrochloride (r = 0.72), and glycyl-L-proline-4-methoxy-beta-naphthylamide hydrochloride (r = 0.69) . There were significant differences in the levels of these three enzymatic activities between sites exhibiting various degrees of clinical severity of gingival inflammation and harboring various proportions of B . gingivalis . The data from this study indicate that measurement of specific enzymatic activities in subgingival samples can be useful in the diagnosis of B . gingivalis-associated periodontitis.

Appl Environ Microbiol, 1988 Aug, 54(8), 1970 - 6
Importance of mucopolysaccharides as substrates for Bacteroides thetaiotaomicron growing in intestinal tracts of exgermfree mice; Salyers AA et al.; We used two approaches to determine whether the mucopolysaccharide chondroitin sulfate is an important source of carbon and energy for Bacteroides thetaiotaomicron in the intestinal tracts of germfree mice . First, we tested the ability of three mutants that grew poorly or not at all on chondroitin sulfate to colonize the intestinal tract of a germfree mouse and to compete with wild-type B . thetaiotaomicron in this model system . One mutant (CG10) was rapidly outcompeted by the wild type . However, since this mutant was unable to grow on chondroitin sulfate because it could not grow on N-acetyl-galactosamine, one of its monosaccharide components, this mutant might also be unable to utilize glycoprotein mucins . Two mutants (46-1 and 46-4) were isolated that grew poorly on chondroitin sulfate but normally on both component sugars . One of them was outcompeted by the wild type, but the percent wild type increased more slowly than with CG10 . In one experiment, the percent wild type never reached 100% . The other (46-4) was not outcompeted by the wild type . These results indicate that, although chondroitin sulfate may be a carbon source in the animal, it is not of major importance . Our second approach was to determine by immunoblot analysis whether a 28-kilodalton outer membrane protein that is produced by B . thetaiotaomicron only when it is grown on chondroitin sulfate or hyaluronic acid was being produced at induced level by B . thetaiotaomicron growing in the ceca of exgermfree mice . There was no evidence for induction of this protein in vivo . Thus, the immunoblot results are consistent with results of the mutant competition experiments.

Clin Invest Med, 1988 Aug, 11(4), 259 - 65
pH-dependent impairment of the neutrophil respiratory burst by the Bacteroides byproduct succinate; Rotstein OD et al.; The mechanisms by which Bacteroides species contribute to the virulence of polymicrobial intraabdominal infections are poorly defined . One potential mechanism may be their ability to inhibit host defenses, thereby permitting their co-pathogens to survive and exert their intrinsic virulence . The purpose of these studies was to examine the effect of the major Bacteroides byproduct, succinate, on the generation of the respiratory burst by neutrophils . Succinate caused a dose-dependent inhibition of both superoxide and hydrogen peroxide production . This phenomenon was markedly pH-dependent, i.e . inhibition occurred following incubation of cells in succinate at pH 5.5 but not at pH 7.4 . It was further hypothesized that succinate effected this inhibition by reducing cytoplasmic pH . Presumably, at low pH, succinate in its protonated form traversed the plasma membrane and dissociated within the cytoplasmic space, thereby reducing pH . The cytoplasmic pH was determined fluorimetrically . Succinate-containing medium at pH 5.5 significantly reduced cytoplasmic pH compared to both control medium pH 5.5 and succinate medium pH 7.4 . In further support of the hypothesis, it was shown that uptake of 14C-succinate by neutrophils was 8-fold increased at pH 5.5 compared to pH 7.4 . Reduced temperature (4 degrees C) protected cells from the inhibitory effect of succinate at pH 5.5 . Measurements of cytoplasmic pH and uptake of 14C-succinate suggested that this protection was achieved by retarding the uptake of succinic acid at low temperature . These studies suggest that fatty acid production by Bacteroides species in the acid milieux of an infection may be a potential mechanism by which Bacteroides species enhance the virulence of mixed infections.

J Bacteriol, 1988 Jul, 170(7), 2923 - 32
Purification and characterization of a chloride-stimulated cellobiosidase from Bacteroides succinogenes S85; Huang L et al.; A cellobiosidase with unique characteristics from the extracellular culture fluid of the anaerobic gram-negative cellulolytic rumen bacterium Bacteroides succinogenes grown on microcrystalline cellulose (Avicel) in a continuous culture system was purified to homogeneity by column chromatography . The enzyme was a glycoprotein with a molecular weight of approximately 75,000 and an isoelectric point of 6.7 . When assayed at 39 degrees C and pH 6.5, the activity of the enzyme with p-nitrophenyl-beta-D-cellobioside as the substrate was stimulated by chloride, bromide, fluoride, iodide, nitrate, and nitrite, with maximum activation (approximately sevenfold) occurring at concentrations ranging from 1.0 mM (Cl-) to greater than 0.75 M (F-) . The presence of chloride (0.2 M) did not affect the Km but doubled the Vmax . In the presence of chloride (0.2 M), the pH optimum of the enzyme was broadened, and the temperature optimum was increased from 39 to 45 degrees C . The enzyme released terminal cellobiose from cellotriose and cellobiose and cellotriose from longer-chain-length cellooligosaccharrides and acid-swollen cellulose, but it had no activity on cellobiose . The enzyme showed affinity for cellulose (Avicel) but did not hydrolyze it . It also had a low activity on carboxymethyl cellulose.

J Bacteriol, 1988 Jul, 170(7), 2914 - 22
Isolation and characterization of endoglucanases 1 and 2 from Bacteroides succinogenes S85; McGavin M et al.; Two endoglucanases designated EG1 and EG2 were purified by column chromatography from the nonsedimentable extracellular culture fluid of Bacteroides succinogenes S85 . They accounted for approximately 32 and 11%, respectively, of the total endoglucanase present in the nonsedimentable fraction . The most active enzyme (EG1) had a molecular weight of 65,000, pI of 4.8, and temperature and pH optima of 39 degrees C and 6.4, respectively . The Km for carboxymethyl cellulose was 3.6 mg/ml, and the Vmax was 84 U/mg . The major products of cellulose hydrolysis catalyzed by EG1 were cellotriose and cellobiose . EG2 was present as two components with molecular weights of 118,000 and 94,000 . The two components had nearly identical cyanogen bromide peptide maps, thereby indicating that the 94,000-dalton component was a proteolytic degradation product of the 118,000-dalton enzyme . The larger component, which was more abundant in the culture fluid than the smaller form was, had a Km of 12.2 mg/ml and a Vmax of 10.4 U/mg . It was a basic protein with a pI of 9.4, a temperature optimum of 39 degrees C, and a pH optimum of 5.8 . The major product of cellulose hydrolysis was cellotetraose . EG2 exhibited specific binding to acid-swollen cellulose, whereas EG1 did not, and neither of them had affinity for crystalline cellulose . Based on the substrate specificities and the affinities of the two enzymes for cellulose, we postulated that EG2 is involved in the early stages of cellulose hydrolysis and that EG1 is active primarily on the products arising from EG2.

Infect Immun, 1988 Jul, 56(7), 1754 - 9
Bacteroides vulgatus outer membrane antigens associated with carrageenan-induced colitis in guinea pigs; Breeling JL et al.; Previous experiments with the carrageenan model for ulcerative colitis demonstrated that the inflammatory response in guinea pigs can be enhanced by immunization with Bacteroides vulgatus and subsequent feeding of this organism to experimental animals . The studies reported here show that antigens extractable from the bacterial outer membrane by EDTA are responsible for this effect . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to analyze the outer membrane proteins from various strains as well as the lipopolysaccharides (LPS) extractable by the phenol-water method . Although the observed pattern of outer membrane proteins was complex, the strains could be divided into two electrophoretic types (phenons) on the basis of immunoblotting against a panel of antisera . Cross-absorbed antisera used in immunoblotting experiments identified four outer membrane proteins uniquely associated with the phenon capable of enhancing the colitis inflammatory response . These proteins had molecular weights of 100,000, 57,000, 34,000, and 21,000 when measured in 8% to 12% acrylamide gradient sodium dodecyl sulfate gels . Other antigens identified included at least one type of smooth LPS, three types of rough LPS, and a common antigen of 30,000 molecular weight among the strains of B . vulgatus tested . The outer membrane preparations were used in animal immunization and challenge experiments, and the severity of colitis was correlated with one electrophoresis type . The potential role of membrane proteins in the enhancement of colitis is discussed.

Heart Lung, 1988 Jul, 17(4), 335 - 8
Anaerobic wound infection: Bacteroides mediastinitis after cardiovascular surgery; Czachor JS et al.; A case of postoperative anaerobic mediastinitis after coronary artery bypass grafting is reviewed . One of the causative organisms, Bacteroides oralis, has never previously been described as a pathogen causing mediastinitis after median sternotomy incision . There was associated Bacteroides fragilis bacteremia . Only three cases of Bacteroides species mediastinitis after open heart surgery have been reported . This anaerobic bacterium remains a rare pathogen in median sternotomy infections despite the increasing number of cases of mediastinitis seen in association with the burgeoning number of patients undergoing cardiac surgery . Multiple risk factors may contribute to mediastinal infections, which occur in about 2% of patients undergoing coronary artery surgery . When infection occurs, aerobic and anaerobic wound cultures should be made and appropriate antimicrobial and surgical therapy instituted.

J Antimicrob Chemother, 1988 Jul, 22 Suppl A, 63 - 71
Antibiotic resistance in anaerobic bacteria; Tally FP et al.; An improved understanding of the mechanisms of resistance and transfer in Bacteroides fragilis has been gained over the past decade . B . fragilis resistance to most penicillins is largely due to production of chromosomal beta-lactamases, although recent findings indicate these micro-organisms can acquire novel beta-lactamases, which can even inactivate imipenem . Several of the beta-lactamases of B . fragilis are transferable . Most of our understanding of transferable antimicrobial resistance in Bacteroides spp . has been gained through studies of the clindamycin-erythromycin resistance determinant found on pBFTM10 . This resistance is encoded on a transposon and is widely distributed among the naturally occurring clindamycin-resistant isolates . Recent studies have shown that DNA can be transferred from Escherichia coli to B . fragilis, from one B . fragilis to another, and from B . fragilis back to E . coli . Data from a large survey in the United States indicate that susceptibility patterns of B . fragilis differ in each of the eight participating centres . Overall, piperacillin and cefoxitin have been found to be the most active beta-lactam agents.

Res Vet Sci, 1988 Jul, 45(1), 68 - 71
Antibody responses of sheep vaccinated with foot rot vaccines; Ferrier GR et al.; Enzyme-linked immunosorbent assay (ELISA) and crossed immunoelectrophoresis (IEP) were used to investigate antibody responses of sheep vaccinated with a double adjuvanted or single adjuvanted commercial foot rot vaccine . ELISA detected an antibody response of greater magnitude to the double adjuvant vaccine compared with the single adjuvant vaccine . Sera from sheep vaccinated with double adjuvant vaccine recognised at least six antigens of Bacteroides nodosus in crossed IEP while sera from the single adjuvant vaccinated sheep recognised one antigen . The use of non-denatured antigens of B nodosus in ELISA and crossed IEP enabled quantitative comparisons of antibody responses to the different foot rot vaccines to be made.

Arzneimittelforschung, 1988 Jul, 38(7), 866 - 8
{The effect of a combination of ampicillin and sulbactam against clinical anaerobic isolates}; Werner H et al.; Effect of a Combination of Ampicillin and Sulbactam on Clinical Isolates of Anaerobic Bacteria . The antimicrobial susceptibility of 182 recent clinical isolates of anaerobic bacteria to ampicillin alone, ampicillin plus 1 mg/l sulbactam, ampicillin plus 5 mg/l sulbactam, and cefoxitin was studied by means of agar dilution tests . The ampicillin-sulbactam combination (Unacid) was most effective against species of the Bacteroides fragilis group, the MIC90 of ampicillin plus 5 mg/l sulbactam for B . fragilis being less than or equal to 1 mg/l, compared to 256 mg/l of ampicillin, 4 mg/l of ampicillin plus 1 mg/l sulbactam, and 8 mg/l of cefoxitin . No significant difference between ampicillin alone and in combination with sulbactam was observed against gram-positive anaerobic rods or cocci.

Pathology, 1988 Jul, 20(3), 260 - 3
Susceptibility of 114 isolates of the Bacteroides fragilis group to imipenem and eight other antimicrobial agents; Downes J et al.; The minimal inhibitory concentrations (MICs) of the newer beta-lactam antibiotic, imipenem, were compared with those of cefoxitin, cefotetan, penicillin, amoxycillin, ticarcillin and metronidazole against 114 clinical isolates of the Bacteroides fragilis group of anaerobic organisms . The ability of clavulanic acid, a beta-lactamase inhibitor, to potentiate the in vitro activity of amoxycillin and ticarcillin was also studied . Using an agar dilution technique we found imipenem to be the most active beta-lactam antibiotic tested having an MIC50 of 0.25 microgram/ml and inhibiting all isolates at a concentration of 4 micrograms/ml . Metronidazole had comparable activity with a MIC50 of 0.5 microgram/ml and all isolates inhibited by 1 microgram/ml . Cefoxitin and cefotetan showed similar activity both with a MIC50 of 8 micrograms/ml against the B . fragilis group, while penicillin, amoxycillin and ticarcillin all had a MIC50 of 16 micrograms/ml . Clavulanic acid significantly reduced the MIC50 of amoxycillin and ticarcillin to 0.5 micrograms/ml and 0.25 micrograms/ml, respectively.

Antimicrob Agents Chemother, 1988 Jul, 32(7), 1097 - 9
Outer membrane permeation of Bacteroides fragilis by cephalosporins; Yotsuji A et al.; Outer membrane permeation of Bacteroides fragilis by cephalosporins was examined by a previously described method . The permeation parameters of cephalosporins in B . fragilis were close to 10(-5) cm3/min per microgram of cell dry weight . These values were about an order of magnitude lower than those in Escherichia coli . In B . fragilis, the permeation was not directly proportional to the hydrophilicity of cephalosporins, and the ion selectivity was weak.

J Periodontol, 1988 Jul, 59(7), 431 - 8
Comparison of cultural methods and DNA probe analyses for the detection of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Bacteroides intermedius in subgingival plaque samples; Savitt ED et al.; The purpose of this study was to compare DNA probe analyses to cultural methods for detecting three periodontal pathogens, Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Bacteroides intermedius, in human subgingival plaque . Subgingival sites from patients diagnosed as either healthy or showing evidence of gingivitis or juvenile or adult periodontitis were sampled using two paper points . The number of these pathogens from one paper point was determined using microbiologic media and speciated by biochemical tests . Results were then compared to bacterial numbers obtained from the other paper point using species-specific DNA probes . In 60 samples from the disease group, DNA probe analysis demonstrated 100% effectiveness in detecting A . actinomycetemcomitans and B . intermedius and 91% effectiveness in detecting B . gingivalis at culture positive levels (greater than or equal to 10(3) cells) . In addition, probe assays frequently identified these pathogens in samples that were culture negative . Probe analysis revealed a better correlation between presence of a pathogen and clinical evidence of disease on an individual patient basis . In contrast, most samples taken from sites of healthy individuals showed undetectable levels of all three pathogens as determined by both techniques . These results suggest that DNA probe technology is at least equivalent and often superior to cultural methods for detecting A . actinomycetemcomitans, B . gingivalis, and B . intermedius in human subgingival plaque samples.

Ann Clin Lab Sci, 1988 Jul-Aug, 18(4), 326 - 36
Post-antibiotic effect in Bacteroides fragilis group; Siverhus DJ et al.; Post-antibiotic effect (PAE) is the transient suppression of bacterial growth after brief antimicrobial exposure . While numerous reports have described PAE with aerobic and facultative microorganisms, virtually no studies have been conducted with anaerobic isolates . Intraabdominal isolates of the Bacteroides fragilis group were exposed for one hour to antibiotic (cefoxitin, cefotetan, and imipenem) concentrations two to four times the minimal inhibitory concentration (MIC) . Post-antibiotic effect was described as the difference between the time required for microbial growth in the test versus the control to increase one Log10 above the quantitation observed immediately after drug removal . Bacteroides fragilis, B . ovatus, B . thetaiotaomicron and B . vulgatus exhibit PAEs for all test compounds . The time intervals for the PAEs were strain variable and ranged from six to 50 hours . No PAE was demonstrated with B . distasonis strains by the broth dilution technique . The results suggest that brief high dose exposure of some members of the B . fragilis group to anaerobe active beta-lactams produces a prolonged suppression in growth . In theory, a prolonged PAE could influence the dosage regimentation of selective antibiotics.

J Clin Periodontol, 1988 Jul, 15(6), 353 - 9
Combined antibiotic (metronidazole) and mechanical treatment effects on the subgingival bacterial flora of sites with recurrent periodontal disease; Gusberti FA et al.; 5 patients in maintenance, 1-3 years after periodontal therapy who showed sites with reinfected pockets and bleeding despite regular recall visits were selected . Darkfield microscopy from 3 sites in each patient showed an average of 41% spirochetes and 21% motile rods . Probing depths ranged from 7 to 9 mm and loss of clinical attachment from 6 to 13 mm in these sites . The patients were given 3 times 250 mg/day of metronidazole (Flagyl) for 10 days . Darkfield microscopy and microbiological cultures of the subgingival plaque were performed twice prior to the study, at the end of the medication and after 3 weeks, 3 and 6 months . The plaque and gingival indices, probing depth and loss of clinical attachment were recorded . During the medication and at 3 and 6 months, the teeth were scaled and root planed . The samples were obtained with 3 paper points and cultured anaerobically in the glove box on non-selective and selective media and representative bacterial colonies identified by aerobic growth, gram stain and rapid biochemical tests . Presumptive pathogenic micro-organisms including Bacteroides were identified . The % of spirochetes, motile rods and non-motile bacteria were enumerated by darkfield microscopy . The clinical results show that administration of metronidazole and repeated root planing significantly decreased gingival inflammation, probing depth and loss of clinical attachment in reinfected sites . After treatment, these sites harbored significantly less spirochetes and more non-motile bacteria, while motile rods tended to return to baseline levels with time . The combined antibiotic and mechanical therapy resulted in a statistically significant decrease of gram-negative rods, Fusobacteria and Bacteroides gingivalis over 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Control Hosp Epidemiol, 1988 Jun, 9(6), 250 - 4
Surgical complications related to insertion of penile prostheses with emphasis on infection and cost; Goetz A et al.; We initiated a prospective study of penile prosthesis implant surgery to evaluate risk factors for infection and other complications . Twenty-one patients admitted for surgery or related complications were evaluated over a seven-month period . The two types of penile prostheses implanted were (1) inflatable and (2) semi-rigid . Nine of 21 patients (43%) developed postoperative complications . Although cephapirin and gentamicin were given prophylactically, four of nine patients had four wound infections and one case of pneumonia . One case of Bacteroides fragilis bacteremia was due to stool incontinency during surgery . In two of the wound infections, removal and reinsertion of the prosthesis was necessary . Other complications included hypotension during surgery, prosthesis malfunction and malposition, and urethral tears . There were no significant associations between infection and age, length of surgery, or type of prosthesis used . These complications contributed to prolonged hospital stay and readmission (87 extra days for the infected patients at a cost of $44,000) . Antibiotic costs to treat the infections totaled $1,900 . Prospective evaluation by infection control practitioners of various elective surgeries can be useful in quantitating the complication rate and targeting patients at risk, with the goal of minimizing hospital costs.

South Med J, 1988 Jun, 81(6), 781 - 2
Bacteroides fragilis endocarditis; Jackson RT et al.; We recently diagnosed and treated an unusual case of primary endocarditis due to Bacteroides fragilis, for which no underlying etiology was found . Antibiotic treatment involved multiple parenteral and oral antibiotics, and sensitivity studies allowed choice of antibiotics . Despite complications, the patient was cured . Few cases of Bacteroides fragilis endocarditis have been reported, and therapy has changed with newer antibiotics.

Aust N Z J Surg, 1988 Jun, 58(6), 514 - 5
Primary iliac-appendiceal fistula; Chambers JL et al.; Primary aorto-appendiceal fistula has been reported only once previously . A further case is presented in which bleeding, per rectum, occurred in association with rupture of an aorto-iliac aneurysm adherent to an acutely inflamed appendix . Postoperatively the patient had several complications including permanent asymmetrical L1 paraplegia and delayed presentation of an intramedullary abscess of the femur which grew Bacteroides fragilis organisms . These complications highlight the high morbidity associated with aortocolic fistulae.

Diagn Microbiol Infect Dis, 1988 Jun, 10(2), 81 - 4
Synergistic activity of cefotaxime and desacetylcefotaxime against the Bacteroides fragilis group; Cornick NA et al.; Sensitivities to cefotaxime (CTX) and its metabolite, desacetylcefotaxime (DCTX), alone and in combination, were determined for 77 organisms of the B . fragilis group . Synergy was observed in 23 (30%) of the strains, of which 21 were those that had a MIC to CTX alone of less than or equal to 16 micrograms/ml . In the remaining two strains, which were resistant to CTX alone, one strain was susceptible to the combination, while the second strain was not . In one strain of B . fragilis, the drug combination increased the MIC of CTX, but both the MIC and MBC remained in the susceptible range.

Infect Immun, 1988 Jun, 56(6), 1647 - 51
Serological studies of oral Bacteroides intermedius; Nakazawa F et al.; Bacteroides intermedius is a gram negative, anaerobic microorganism associated with certain forms of human periodontal disease, including adult periodontitis and acute necrotizing ulcerative gingivitis . Previous studies have indicated the presence of two DNA homology groups which could be distinguished by analysis of protein patterns on polyacrylamide gel electrophoresis, as well as at least two serogroups within B . intermedius . The present study examined the serology of B . intermedius and determined the distribution of B . intermedius serogroups in clinical isolates and patient plaque samples . Serological reactions with unabsorbed rabbit antisera and antisera immunoabsorbed with B . intermedius strains demonstrated a previously unreported antigenic group within B . intermedius, serogroup C, in both immunodiffusion and immunofluorescence assays . Of 79 B . intermedius isolates from 68 subjects examined with specific antisera, 55% of the isolates and 52% of the subjects were categorized in serogroup C, 40% of the isolates and 46% of the subjects were in serogroup B, and 5% of the isolates and 6% of the subjects were in serogroup A . In 31 samples of subgingival dental plaque from adolescents known to harbor B . intermedius, 81% demonstrated serogroup B, 16% had serogroup A, and 3% had serogroup C.

Pathol Biol (Paris), 1988 Jun, 36(5 Pt 2), 685 - 9
{Influence of the inoculum effect on minimal inhibitory concentrations of 3 derivatives of 5-nitro-imidazole and 11 other antibiotics on Bacteroides fragilis}; Dusart G et al.; Three nitro-imidazole derivatives and eleven other antibiotics were studied for both their antimicrobial activity and the degree to which they produced inoculum effect on twenty strains of Bacteroides fragilis group . Five inocula were studied ranging from 10(5) to 10(9) CFU/ml . Statistical analysis show the significant influence of inoculum and those of strains . Nitro-imidazole derivatives exhibited a large inoculum effect while other antibiotics exhibited only a minimal to-no-inoculum effect.

Clin Obstet Gynecol, 1988 Jun, 31(2), 488 - 500
Treatment of postcesarean endomyometritis; Yonekura ML; Improved understanding of the microbiology of postcesarean endometritis has dramatically changed the approach to its antibiotic therapy . Initial therapy should include broad-spectrum anaerobic coverage, including against all Bacteroides species, as well as gram-positive and gram-negative aerobic coverage . Moreover, ideally initial therapy should also include coverage of Chlamydia trachomatis . Furthermore, although the use of antibiotic prophylaxis for high-risk patients undergoing cesarean section has significantly decreased their incidence of febrile morbidity, one must remember that prophylactic antibiotics have important bacteriologic effects that may limit the efficacy of monotherapy for the treatment of endometritis in prophylaxis failures.

Am J Surg, 1988 May 31, 155(5A), 24 - 9
Criteria for in vitro susceptibility testing of cefotetan . Correlations with clinical and bacteriologic responses; Barry AL; Standardized in vitro susceptibility testing criteria and quality-control guidelines for cefotetan have been well documented in the scientific literature . Cefotetan and cefoxitin differ in their in vitro spectrums of activity and cannot be used interchangeably for in vitro tests . In vitro susceptibility information failed to correlate with clinical or bacteriologic responses of treated patients when 314 anaerobic bacteria from 145 patients were evaluated . All cefotetan-resistant anaerobic bacteria were eradicated by cefotetan therapy, and 93 percent of patients with resistant strains were clinically curved . Most members of the Bacteroides distasonis-ovatus-thetaiotaomicron group of pathogens were resistant in vitro, but only one strain persisted after cefotetan therapy for a 96.6 percent cure rate . There was better correlation when 2,336 aerobic bacteria from 1,630 infected body sites were considered . Microorganisms susceptible or moderately susceptible by in vitro tests were equally responsive to therapy (95 percent of patients clinically cured and 94 percent of isolates eradicated) . However, strains that were resistant by in vitro test criteria were less likely to respond clinically . Development of resistance during therapy or superinfections (1.7 percent) were not found to be clinically important problems with cefotetan chemotherapy.

J Biol Chem, 1988 May 15, 263(14), 6683 - 7
Sequence of the phosphothreonyl regulatory site peptide from inactive maize leaf pyruvate, orthophosphate dikinase; Roeske CA et al.; The regulatory site peptide sequence of phosphorylated inactive pyruvate, orthophosphate dikinase from maize leaf tissue was determined by automated Edman degradation analysis of 32P-labeled peptides purified by reversed-phase high performance liquid chromatography . The overlapping phosphopeptides were products of a digestion of the {beta-32P}ADP-inactivated dikinase with either trypsin or Pronase E . The sequence is Thr-Glu-Arg-Gly-Gly-Met-Thr(P)-Ser-His-Ala-Ala-Val-Val-Ala-Arg . The phosphothreonine residue, which appeared as either an anomalous proline or an unidentifiable phenylthiohydantoin derivative during sequencing, was verified by two-dimensional phosphoamino acid analysis of the phosphopeptides and by resequencing the tryptic peptide after dephosphorylation with exogenous alkaline phosphatase . This sequence, starting at position 4, is completely homologous to the previously published sequence of the tryptic dodecapeptide harboring the catalytically essential (phospho)histidyl residue in the active-site domain of the dikinase from the nonphotosynthetic bacterium, Bacteroides symbiosus (Goss, N.H., Evans, C.T., and Wood, H.G . (1980) Biochemistry 19, 5805-5809) . These comparative results indicate that the regulatory phosphothreonine causing complete inactivation of maize leaf dikinase is separated from the critical active-site (phospho)histidine by just one intervening residue in the primary sequence.

Antimicrob Agents Chemother, 1988 May, 32(5), 717 - 22
Susceptibility of the Bacteroides fragilis group in the United States: analysis by site of isolation; Cuchural GJ Jr et al.; An ongoing survey of the susceptibility of the Bacteroides fragilis group of bacteria was continued at New England Medical Center in 1984 and 1985 . A total of 1,229 strains were obtained from eight centers in the United States . These results were compared with those for 1,847 isolates tested in 1981 through 1983 . The most active beta-lactam drugs were imipenem and ticarcillin-clavulanic acid (Timentin), which had a less than 1% resistance rate . No metronidazole- or chloramphenicol-resistant isolates were found during the 5 years of the study . Isolates obtained from blood, perinatal, and bone sites of infection were more resistant to a variety of antimicrobial agents . Susceptibility patterns of the members of the B . fragilis group varied at the eight hospitals and among species . These data indicate the need for determining the susceptibility patterns for the B . fragilis group of organisms at each hospital.

Appl Environ Microbiol, 1988 May, 54(5), 1079 - 84
Use of phylogenetically based hybridization probes for studies of ruminal microbial ecology; Stahl DA et al.; To address the long-standing need for more precise descriptions of natural microbial ecosystems, 16S rRNAs were used to track certain species and phylogenetically coherent groups of microorganisms in their natural setting without culturing . Species- and group-specific 16S rRNA-targeted oligonucleotide hybridization probes were developed to enumerate various strains of Bacteroides succinogenes and Lachnospira multiparus-like organisms in the bovine rumen before, during, and after perturbation of that ecosystem by the addition of the ionophore antibiotic monensin . Based on probe hybridization, relative numbers of L . multiparus-like organisms were depressed about 2-fold during monensin addition and demonstrated a transient 5- to 10-fold increase immediately after removal of the antibiotic from the diet . The most pronounced population changes were observed among different strains of B . succinogenes, as evaluated by three hybridization probes . One probe hybridized to all strains, whereas the other two identified genetically distinct groups represented by strains isolated from the rumen and from the ceca of nonruminants . The rumen-type strains predominated on most days (ca . 0.2 to 0.8% of total ribosome numbers) . Their proportion transiently increased about fivefold immediately after the addition of monensin to the feed and then transiently fell below the average premonensin level . During this time (ca . 2 weeks after monensin addition) the cecal type predominated (ca . 0.1 to 0.2%) . Cultural enumeration of B . succinogenes on nonselective agar and by observing clearings in cellulose agar media were largely unsuccessful due to the low number of organisms present and the predominance of other cellulolytic species.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutat Res, 1988 May, 208(1), 9 - 15
Fecapentaenes and their precursors throughout the bowel--results of an autopsy study; Schiffman MH et al.; The fecapentaenes are potent mutagens found in the stool of some humans and pigs . These compounds are produced by Bacteroides species in the gut from an uncharacterized family of precursor compounds, and have been postulated to pose a risk of human colorectal cancer . To better understand fecapentaene production in vivo, and to determine if excreted levels measured in epidemiologic studies are representative of the entire colon, fecapentaenes were assayed from multiple sites in the bowel in an autopsy study of 16 humans and 2 pigs . An indirect measurement of fecapentaene precursors was also made . Colonic concentrations of fecapentaenes and precursors varied widely between individuals, but were consistent for each individual throughout the colon . In addition, the measurements of rectal contents, assumed to approximate values in excreted stool, were equivalent to measurements from the colon.

Appl Environ Microbiol, 1988 May, 54(5), 1163 - 9
Effects of alkaline hydrogen peroxide treatment on in vitro degradation of cellulosic substrates by mixed ruminal microorganisms and Bacteroides succinogenes S85; Lewis SM et al.; The effects of sodium hydroxide (NaOH) and alkaline hydrogen peroxide (AHP) treatments on wheat straw (WS) and various cellulosic substrates were determined by measuring susceptibility to degradation by mixed ruminal organisms or Bacteroides succinogenes S85 . In vitro incubations were used to measure differences in fermentation resulting from each successive step in the AHP treatment process . In vitro incubations through 48 or 108 h were conducted to measure these differences . The AHP treatment of WS increased (P less than 0.05) dry matter, neutral detergent fiber, and acid detergent fiber degradation over control WS when these substrates were incubated with mixed ruminal microorganisms or B . succinogenes S85 . Fermentations containing AHP-treated WS had greater (P less than 0.05) microbial purine (RNA) and volatile fatty acid concentrations by 12 h compared with those containing untreated or NaOH-treated WS . Xylose in AHP-treated WS was utilized more extensively (P less than 0.05) by 12 h compared with the xylose of untreated or NaOH-treated WS . Treatment with AHP removed 23% of the alkali-labile phenolic compounds from WS . When substrates with high levels of crystalline cellulose (raw cotton fiber, Solka floc, and Sigmacell-50) were treated with NaOH or AHP and incubated for 108 h with B . succinogenes S85, extent of acid detergent fiber degradation of cotton fiber and Sigmacell-50 was similar to that of their respective controls . Sodium hydroxide and AHP treatments were effective in increasing acid detergent fiber degradation of the Solka floc which contained, on average, 3.3 and 4.8 percentage units more acid detergent lignin and hemicellulose, respectively, than cotton fiber and Sigmacell-50.(ABSTRACT TRUNCATED AT 250 WORDS)

J Clin Microbiol, 1988 May, 26(5), 1063 - 5
Rapid characterization of oral and nonoral pigmented Bacteroides species with the ATB Anaerobes ID system; van Winkelhoff AJ et al.; The ATB Anaerobes ID system (API SYSTEM, La Balme Les Grottes, France) was evaluated for its ability to differentiate between species of the pigmented Bacteroides group . This identification system is based on the degradation of chromogenic substrates in combination with sugar fermentation reactions . The results showed that the ATB system can be useful for differentiation between the 10 pigmented Bacteroides species . However, additional tests may be necessary.

Infect Immun, 1988 May, 56(5), 1096 - 100
Effect of environmental pH on enzyme activity and growth of Bacteroides gingivalis W50; McDermid AS et al.; Since the pH of the gingival crevice increases from below neutrality in health to above pH 8 in disease, we decided to investigate the effect of environmental pH on the growth and enzyme activity of Bacteroides gingivalis W50 . Cells were grown in a chemostat under hemin-excess conditions over a range of pH values; stable growth was observed only between pH 6.7 and 8.3, with the maximum yields obtained between pH 7.0 and 8.0 . The enzyme profile of cells varied markedly with pH . Enzymes with a specificity for gingival connective tissue (collagenase, hyaluronidase) were produced optimally at or below neutral pH, whereas trypsinlike activity increased with the growth pH and was maximal at pH 8.0 . Chymotrypsinlike activity was generally low, although its activity was highest at the extremes of growth pH, i.e., at pH 6.7 and 8.3 . Inhibitor studies provided evidence that the breakdown of collagen involved the concerted action of both a collagenase and the trypsinlike enzyme . The ratio of trypsin to collagenolytic activity rose from 1:1 during growth at neutral pH and below to almost 7:1 during growth at pH 8.3 . Thus B . gingivalis appears to be uniquely adapted as a periodontopathic organism in that under environmental conditions likely to prevail during the initial stages of pocket development it produces maximally those enzymes with a tissue-damaging potential . Then, as the pH of the pocket rises during the host inflammatory response, the activity of the trypsinlike enzyme increases markedly, which may enable cells to inactivate key components of the host defenses such as immunoglobulins and complement.

Eur J Obstet Gynecol Reprod Biol, 1988 May, 28(1), 39 - 52
Clinical and laboratory findings in women with bacterial vaginosis and trichomoniasis versus controls; van der Meijden WI et al.; We report comprehensively on the clinical and laboratory findings in 30 women with bacterial vaginosis (BV), 30 with vaginal trichomoniasis and 30 with normal secretions . Women with trichomoniasis were more often divorced (chi 2 test, p much less than 0.001), more often complained of dyspareunia (chi 2 test, p less than 0.05), frequently had discharge present in the vaginal vestibule, and showed one or more signs of vaginitis in half the cases . A 'moth-eaten' cervix was seen in only four women (13%) with trichomoniasis, but can be considered pathognomonic of the condition . While the main characteristics of vaginal secretions, i.e . amount, consistency, colour, absence or presence of gas and odour, are only poorly discriminative between BV and trichomoniasis, they can be of much help in distinguishing between 'abnormal' and--probably--normal secretions . Parabasal cells were found in the wet mount of 19 women (73%) with trichomoniasis . Epithelial cell clusters were a prominent finding in controls but were virtually absent in the other two groups . We detected curved rods in 15 women (50%) with BV, but in none of the women with trichomoniasis or normal secretions . There were only minor differences in the results of bacterial cultures in cases of BV and trichomoniasis . Bacteroides and Peptostreptococcus species were the predominant anaerobes in both groups . Gardnerella vaginalis was significantly more often isolated from women with BV than from controls (chi 2 test for trend, p less than 0.001) . Gas-liquid chromatography showed the presence of succinate in only two cases of BV . Lactate was found in all controls but one . Ethylation of vaginal samples probably reduces the risk of over-emphasizing the presence of succinate and lactate . It is concluded that BV and trichomoniasis are both characterized by the overgrowth of anaerobic bacteria and that there is a considerable overlap in clinical and laboratory findings . Microscopy of the wet mount should be considered the most powerful diagnostic tool.

J Clin Periodontol, 1988 May, 15(5), 331 - 7
Longitudinal study of untreated periodontitis (II) . Microbiological findings; MacFarlane TW et al.; 11 volunteer subjects with advanced chronic periodontitis participated in a 1-year longitudinal clinical and microbiological study . Subgingival plaque was collected at each of 7 visits from 148 pre-selected sites in the left jaw quadrants (test sites) and on the first and last visits, only from 117 sites in the left jaw quadrants (control sites) . All sites were examined clinically at each of the 7 visits, and the microbiological markers investigated were the % spirochaetes and % black pigmented Bacteroides species in subgingival plaque . At the completion of the study, the sequential changes in probing attachment level at each site were subjected to regression analysis to determine the direction and extent of attachment change . Possible correlations between attachment change and % spirochaetes or % black-pigmented bacteroides were investigated using both individual sites and individual subjects . No significant differences were observed in either of the microbial variables between test and control sites . Possible correlations between the microbiological markers and attachment changes were investigated at baseline, at the 12-month visit and using the microbial data accumulated over all 7 visits . Significant differences were observed only at the 12-month visit when the % spirochaetes of both test and control sites were significantly lower in subjects showing the greatest improvement in attachment level . Overall, these results indicate that quantification of either spirochaetes or black-pigmented Bacteroides species cannot be used reliably to identify or predict disease-active sites.

J Dent Res, 1988 May, 67(5), 807 - 11
Protective efficacy of active and passive immunizations against experimental infection with Bacteroides gingivalis in ligated hamsters; Okuda K et al.; The protective efficacy of immunization against Bacteroides gingivalis infection was examined in hamsters . Whole cells or extracted hemagglutinin of B . gingivalis 381 was injected with incomplete Freund adjuvant into the inguinal regions of hamsters . Two weeks after the rats received a booster injection, cotton threads were tied coronally to the gingival margins of the mandibular first molars, and then a streptomycin-resistant B . gingivalis 381R' strain was inoculated into the rats' oral cavities . The subcutaneous immunizations resulted in slight reductions in the numbers of B . gingivalis on the ligature threads compared with the sham-immunized group . Peroral administration of whole cells of B . gingivalis to hamsters elicited salivary immunoglobulin responses, but no reduction of B . gingivalis 381R' colonization was found in this group . Repeated passive immunizations with rabbit antiserum to B . gingivalis into the oral cavities of the hamsters resulted in a reduction in the number of organisms in the periodontal region.

Acta Chir Scand, 1988 May-Jun, 154(5-6), 379 - 83
Acute experimental suppurative pancreatitis in the rat; Tarpila E et al.; Acute pancreatitis was induced in rats by infusing sodium taurodeoxycholate with or without Escherichia coli and Bacteroides fragilis into the bile-pancreatic duct . Survival did not differ between the 'noninfected bile group' (NIB) and the 'infected bile group' (IB) . At standardized macroscopic evaluation, pancreatitis was more severe in the IB group (p less than 0.05) . Histologic examination on day 7 showed suppuration of pancreatic tissue in 6/7 IB and 3/14 NIB rats (p less than 0.05) . Bacteriologic culture of pancreatic tissue was positive in 6/8 IB and 3/17 NIB rats (p less than 0.01) . Bacterial culture of blood, peritoneal fluid of pulmonary tissue was seldom positive . Concordance between microscopically observed suppuration and positive bacterial culture was almost total . Recall antigen skin testing indicated anergy in the IB group, while the NIB group showed moderately diminished reaction (p less than 0.001) . Similar increase of S-fibrinogen was found on day 3 in both groups, but complement factor C3 was reduced only in the IB group . This experimental model, with suppurative pancreatitis induced by intraductal infusion of an infected bile salt, may be useful for studies of systemic complications in acute pancreatitis.

J Periodontol, 1988 Apr, 59(4), 259 - 65
Intragingival occurrence of Actinobacillus actinomycetemcomitans and Bacteroides gingivalis in active destructive periodontal lesions; Saglie FR et al.; A total of six active and six nonactive sites from six untreated periodontitis patients were examined for intragingival presence of Actinobacillus actinomycetemcomitans and Bacteroides gingivalis . The active destructive periodontal disease was determined by the "tolerance method." The method of immunoperoxidase was used in the identification of intragingival microorganisms in active and nonactive periodontal sites . Light microscopic sections of gingival tissues consecutive to those with gram stain, revealing presence of bacteria (substantiated by electron microscopy), were stained with peroxidase-labeled antibodies against A . actinomycetemcomitans and B . gingivalis . B . gingivalis was found to be significantly elevated in the connective tissue of active sites when compared to nonactive sites . A statistically significant border-line difference was found between active and nonactive sites in the connective tissue invaded by A . actinomycetemcomitans . Our findings plus the well established periodontopathic potential of A . actinomycetemcomitans and B . gingivalis support the concept that these bacteria are important invasive pathogenic agents in periodontitis.

J Antimicrob Chemother, 1988 Apr, 21(4), 451 - 9
Efficacy of amoxycillin/clavulanic acid in experimental Bacteroides fragilis/Escherichia coli mixed infections; Beale AS et al.; The efficacy of amoxycillin/clavulanic acid was compared with those of metronidazole, cefuroxime, metronidazole/ampicillin, metronidazole/gentamicin and metronidazole/cefuroxime, in experimental mixed infections produced in mice by subcutaneous inoculation of amoxycillin-resistant strains of Bacteroides fragilis and Escherichia coli . The combination of metronidazole/ampicillin failed to inhibit the growth of E . coli, and exerted only a transient effect on the numbers of Bact . fragilis in the groin abscesses . In contrast, amoxycillin/clavulanic acid prevented the development of the infection, eliminating both organisms . Metronidazole and cefuroxime, alone and in combination, were less effective than amoxycillin/clavulanic acid in inhibiting the growth of the infecting organisms . These results demonstrate the clinical potential of amoxycillin/clavulanic acid in prophylaxis, or in the therapy of mixed aerobe/anaerobe infections.

Clin Pharm, 1988 Apr, 7(4), 285 - 302
Use of cephalosporins with enhanced anti-anaerobic activity for treatment and prevention of anaerobic and mixed infections; DiPiro JT et al.; The microbiology, adverse-effect profiles, pharmacokinetics, published results of comparative clinical trials, and costs of cephalosporins with enhanced antianaerobic activity are reviewed . Cefoxitin, ceftizoxime, cefotetan, and moxalactam have been used as single agents in the treatment or prophylaxis of anaerobic or mixed aerobic and anaerobic infections, including intra-abdominal, female genital tract, and soft-tissue infections . None of these agents is as active against Bacteroides species as is clindamycin or metronidazole, but differences among the four cephalosporins do not appear to be clinically important . These agents differ somewhat in their activity against gram-positive and gram-negative bacteria . The majority of adverse reactions to these agents are immunological; disulfiram-like reactions and alterations in normal hemostasis have also been observed with cefotetan and moxalactam . All of these agents are well absorbed after intramuscular injection and produce serum concentrations adequate to treat most infections . Only ceftizoxime and moxalactam produce cerebrospinal fluid concentrations adequate for treatment of gram-negative meningitis . The primary route of elimination is renal, and each agent requires dosage adjustments in patients with renal impairment . Major differences exist among the elimination half-lives of the agents in patients with normal renal function . The decision to use a cephalosporin for treatment of anaerobic infections should be based on the results of clinical trials that have demonstrated the efficacy of the agent . Data are available to support the use of cefoxitin, ceftizoxime, and moxalactam in the treatment of intra-abdominal infections; cefoxitin and moxalactam to prevent infection of traumatic injury to the abdomen; all four agents in the treatment of female genital tract infections; and all four agents for prophylactic use in surgical procedures that may involve enteric anaerobes, especially B . fragilis . Cephalosporins with enhanced antianaerobic activity appear to have similar in vitro microbiological activity and have efficacy similar to that of combination regimens for the treatment and prophylaxis of intra-abdominal infections, abdominal contamination, obstetric and gynecological infections, and soft-tissue infections.

Microb Pathog, 1988 Apr, 4(4), 279 - 87
Outer membrane proteins of Bacteroides fragilis and Bacteroides vulgatus in relation to iron uptake and virulence; Otto BR et al.; A virulent strain B . fragilis BE1 and an avirulent strain B . vulgatus BE20 were grown in a culture medium with and without the addition of a synthetic chelator (Bipyridyl) to induce iron limitation . Cells grew more slowly under iron stress, although the growth rate of the B . vulgatus strain was more affected under these conditions than the strain of B . fragilis . The outer membrane protein profile of these strains was studied in relation to the iron concentration in the growth medium by means of SDS-polyacrylamide gel electrophoresis . Four proteins, with the apparent molecular weights of 89, 49, 44 and 23.5 kDa, were consistently present in the outer membrane of B . fragilis BE1 grown under iron restricted conditions . In B . vulgatus BE20 cells a 44 and a 23.5 kDa protein were absent and only the expression of an 89 kDa protein was clearly seen under these conditions . The iron regulated proteins, particularly the 44 kDa protein, could be involved to an iron uptake mechanism in B . fragilis . So the presence of these proteins might play an important role in the virulence of this anaerobic bacterium.

Antimicrob Agents Chemother, 1988 Apr, 32(4), 584 - 6
Activity of trospectomycin against Bacteroides fragilis and other Bacteroides species; Jacobus NV et al.; The in vitro activity of trospectomycin (U-63366; 6'-n-propyl spectinomycin pentahydrate sulfate) was evaluated against 189 clinical isolates of the Bacteroides fragilis group and 65 Bacteroides species isolates . At less than or equal to 8 micrograms/ml, the activity of trospectomycin compared favorably with those of clindamycin and cefoxitin against B . fragilis, Bacteroides distasonis, and Bacteroides vulgatus, and there was no cross resistance to these three drugs among the strains of the B . fragilis group . All the Bacteroides species were susceptible to trospectomycin . The results of this in vitro study indicate that trospectomycin possesses excellent activity against Bacteroides species.

Antimicrob Agents Chemother, 1988 Apr, 32(4), 598 - 600
Activities of Nigerian chewing stick extracts against Bacteroides gingivalis and Bacteroides melaninogenicus; Rotimi VO et al.; The in vitro activities of extracts of Nigerian chewing sticks against Bacteroides gingivalis and B . melaninogenicus are presented . The greatest inhibitory action was produced by Serindeia werneckei, whereas Fagara zanthoxyloides produced no appreciable inhibitory effect . A generally good correlation was found between the killing curves and MICs . Only extracts of Anogeissus leiocarpus showed acute toxicity in mice.

J Clin Microbiol, 1988 Apr, 26(4), 776 - 7
Evaluation of in vitro methods for testing ceftriaxone against anaerobic bacteria, including quality control guidelines; Barry AL et al.; Tests with 100 anaerobic bacterial isolates demonstrated comparability between ceftriaxone MICs obtained with the reference agar dilution procedure and those obtained with a broth microdilution susceptibility testing procedure . The aerobically incubated thioglycolate disk elution test was also evaluated . Six 30-micrograms ceftriaxone disks in 5 ml of thioglycolate separated strains for which MICs were less than or equal to 32 micrograms/ml from those for which MICs were greater than or equal to 64 micrograms/ml (6% overall discrepancies) . Quality control limits for ceftriaxone agar dilution tests were determined to be as follows: Bacteroides fragilis ATCC 25285, 32 to 128 micrograms/ml; and Bacteroides thetaiotaomicron ATCC 29741, 64 to 256 micrograms/ml.

J Bacteriol, 1988 Apr, 170(4), 1658 - 65
Molecular cloning and sequencing of the gene encoding the fimbrial subunit protein of Bacteroides gingivalis; Dickinson DP et al.; The gene encoding the fimbrial subunit protein of Bacteroides gingivalis 381, fimbrilin, has been cloned and sequenced . The gene was present as a single copy on the bacterial chromosome, and the codon usage in the gene conformed closely to that expected for an abundant protein . The predicted size of the mature protein was 35,924 daltons, and the secretory form may have had a 10-amino-acid, hydrophilic leader sequence similar to the leader sequences of the MePhe fimbriae family . The protein sequence had no marked similarity to known fimbrial sequences, and no homologous sequences could be found in other black-pigmented Bacteroides species, suggesting that fimbrillin represents a class of fimbrial subunit protein of limited distribution.

Appl Environ Microbiol, 1988 Apr, 54(4), 855 - 60
Plasmid-associated transfer of tetracycline resistance in Bacteroides ruminicola; Flint HJ et al.; Tetracycline resistance was transferred at frequencies between 10(-7) and 10(-6) per recipient cell in anaerobic matings between two strains of the strictly anaerobic rumen bacterium Bacteroides ruminicola . The donor strain, 223/M2/7, was a multiple-plasmid-bearing tetracycline-resistant strain from the ovine rumen, and the recipient, F101, was a rifampin-resistant mutant of B14, a bovine strain belonging to B . ruminicola subsp . brevis . Resistance transfer could occur in the presence of DNase, but not in dummy mating mixtures in which filtrate from a donor culture replaced donor cells . Acquisition of tetracycline resistance by the recipient was accompanied by the appearance of a 19.5-kilobase pair plasmid (designated pRRI4) which was homologous with a plasmid of similar size and restriction pattern present in the donor strain . A transconjugant (F115) carrying pRRI4 was also able to act as a donor of tetracycline resistance and plasmid DNA in matings with another recipient . Derivatives of F115 that had spontaneously lost tetracycline resistance lacked detectable plasmid DNA . It is concluded that pRRI4 mediated the transfer of tetracycline resistance . Transfer of resistance was not detectably enhanced by pregrowth of the donor in medium containing tetracycline . Transfer of tetracycline resistance was not detected from 223/M2/7 to a strain, 23 belonging to B . ruminicola subsp . ruminicola.

J Bacteriol, 1988 Apr, 170(4), 1651 - 7
Tetracycline-dependent appearance of plasmidlike forms in Bacteroides uniformis 0061 mediated by conjugal Bacteroides tetracycline resistance elements; Shoemaker NB et al.; Some human colonic Bacteroides strains carry conjugal tetracycline resistance (Tcr) elements, which are thought to be chromosomal . We have found that some of these Tcr elements can mediate the appearance of plasmidlike forms in Bacteroides uniformis 0061 . When B . uniformis 0061, containing a conjugal Tcr element designated Tcr ERL, was grown in medium containing tetracycline (1 microgram/ml), two circular DNA forms were found in the alkaline plasmid preparations: NBU1 (10.3 +/- 0.5 kilobases) and NBU2 (11.5 +/- 0.5 kilobases) . Restriction analysis of NBU1 and NBU2 showed that they were not identical, although Southern blot analysis indicated that they did contain some region(s) of homology . Results of Southern blot analysis also demonstrated that both NBU1 and NBU2 were normally integrated in the chromosome of B . uniformis or in some undetected large plasmid . Although we were unable to determine the exact structure and location of the integrated forms of NBU1 and NBU2 in B . uniformis, they appear to be in close proximity to each other . Neither NBU1 or NBU2 could be detected as a plasmidlike form in cells exposed to UV light, thymidine starvation, mitomycin C, or autoclaved chlortetracycline (50 micrograms/ml) . Four conjugal Tcr elements other than the Tcr ERL element were able to mediate the appearance of NBU1 alone, and two Tcr elements did not mediate the excision of either NBU1 or NBU2 . Three strains from different Bacteroides species contained some DNA sequences which had homology to NBU1 and NBU2.

J Bacteriol, 1988 Apr, 170(4), 1423 - 9
Characterization of a novel tetracycline resistance that functions only in aerobically grown Escherichia coli; Speer BS et al.; A tetracycline resistance (Tcr) gene that was found originally on two Bacteroides plasmids (pBF4 and pCP1) confers tetracycline resistance on Escherichia coli, but only when it is grown aerobically . Using maxicells, we have identified a 44-kilodalton protein which is encoded by the region that carries the Tcr gene and which may be the Tcr gene product . Localization experiments indicate that this 44-kilodalton protein is cytoplasmic . To determine whether the tetracycline resistance gene is expressed under anaerobic conditions, we have constructed a protein fusion between the Tcr gene and lacZ . In strains of E . coli carrying the fusion, beta-galactosidase activity was the same when the cells were grown under anaerobic conditions as when the cells were grown under aerobic conditions . This indicates that the tetracycline resistance gene product is made under anaerobic conditions but does not work . The failure of the Tcr protein to function under anaerobic conditions was not due to a requirement for function of the anaerobic electron transport system, because neither nitrate nor fumarate added to anaerobic media restored tetracycline resistance . Inhibition of the aerobic electron transport system with potassium cyanide did not prevent growth on tetracycline of cells containing the Tcr gene . A heme-deficient mutant, E . coli SHSP19, which carries the Tcr gene, was still resistant to tetracycline even when grown in heme-free medium . These results indicate that functioning of the Tcr gene product is not dependent on the aerobic electron transport system . Thus the requirement for aerobic conditions appears to reflect a requirement for oxygen . Spent medium from an E . coli strain carrying the Tcr gene, which was grown in medium containing tetracycline (50 micrograms/ml), did not inhibit growth of a tetracycline-susceptible strain of E . coli . Thus, the Tcr gene product may be detoxifying tetracycline.

J Protein Chem, 1988 Apr, 7(2), 157 - 64
Amino acid sequences of pilins from serologically distinct strains of Bacteroides nodosus; McKern NM et al.; Amino acid sequences of pilin from a strain of Bacteroides nodosus from serogroup B (234) and serogroup C (217) were determined . The amino-terminal N-methylphenlalanine residue of both proteins was followed by a hydrophobic sequence of 30 residues closely related to the N-terminal sequence of other pili having an amino-terminal residue of N-methylphenylalanine . These data lend support to the hypothesis that in pilins of this type, the amino-terminal sequence functions as a transport signal necessary for pilin to reach its external environment, as well as promoting intersubunit interactions for maintenance of the structural integrity of the pilus . Two hydrophilic hypervariable regions can be discerned across the pilin sequences, indicating possible locations of antigenic domains.

Can J Microbiol, 1988 Mar, 34(3), 299 - 306
Coaggregation among periodontal pathogens, emphasizing Bacteroides gingivalis--Actinomyces viscosus cohesion on a saliva-coated mineral surface; Ellen RP et al.; Teeth offer nonshedding surfaces on which a wide range of bacterial species accumulate as thick, cohesive plaques . Intergeneric coaggregation mediated by specific recognition between surface "cohesins" is thought to contribute to both the cohesiveness of plaque and the sequence in which bacteria colonize the tooth surface . There is some evidence that Gram-positive species, like the efficient tooth colonizer Actinomyces viscosus, enhance subsequent tooth colonization by the more virulent periodontal pathogen Bacteroides gingivalis . To study their mechanism of cohesion, we have developed an in vitro assay that measures the sequential binding of tritium-labeled B . gingivalis to A . viscosus adsorbed to saliva-coated hydroxyapatite beads, mimicking teeth (actinobeads) . The assay yields equilibrium and kinetics data amenable to statistical analysis . The presence of A . viscosus significantly increased the number of B . gingivalis cells bound . Inhibition studies were conducted to test the sensitivity of binding to heat; to various saccharides and sugar amines; to proteolytic treatment of Bacteroides; and to incorporation of various chaotropic agents, increased KCl, and saliva in the suspension buffer . Heating the Bacteroides cells but not the actinobeads diminished Bacteroides adherence . Proteolysis and various saccharides had little, if any, effect . Among chaotropic agents, NaSCN and LiCl reduced numbers of cells bound by 40%, but tetramethylurea had no effect . Increasing the ionic concentration of KCl reduced binding by 50 to 60% . Diluted saliva showed a concentration-dependent inhibition of B . gingivalis adherence to actinobeads . To begin examining B . gingivalis surface molecules significant to these reactions, lipopolysaccharide was extracted by the phenol-water method and analyzed by biochemical assays and polyacrylamide gel electrophoresis.(ABSTRACT TRUNCATED AT 250 WORDS)

Antimicrob Agents Chemother, 1988 Mar, 32(3), 403 - 6
In vitro activity of cefoperazone plus sulbactam compared with that of other antimicrobial agents against anaerobic bacteria; Wexler HM et al.; The activity of two cefoperazone-sulbactam combinations against anaerobic bacteria was tested and compared both with that of cefoperazone alone and with that of other commonly used antimicrobial agents . Imipenem was the most active of the tested agents, followed by chloramphenicol, metronidazole, and cefoperazone-sulbactam (90 to 100% of bacterial growth inhibited) . Clindamycin and cefoxitin inhibited approximately 80%, cefoperazone inhibited 63%, and penicillin G inhibited 47% of the strains tested . The agents were variable in activity against the Bacteroides fragilis group, with percents susceptible as follows: cefoperazone-sulbactam, imipenem, metronidazole, and chloramphenicol, 99 to 100%; cefoxitin and clindamycin, approximately 80%; cefoperazone, 49%; and penicillin G, 15.5%.

Antimicrob Agents Chemother, 1988 Mar, 32(3), 385 - 90
National Committee for Clinical Laboratory Standards agar dilution susceptibility testing of anaerobic gram-negative bacteria; Brown WJ; One hundred nine recent clinical isolates of anaerobic gram-negative bacteria were tested in triplicate by the National Committee for Clinical Laboratory Standards agar dilution procedure for their susceptibility to 32 antimicrobial agents . All isolates were inhibited by imipenem, but there were significant numbers of strains resistant to other beta-lactam drugs, and therefore the in vitro response to these antimicrobial agents cannot be predicted . This was particularly true for the bile-resistant or Bacteroides fragilis group . beta-Lactamase production was detected in 82% of the bacteroides with the nitrocefin test . Clavulanic acid combined with amoxicillin and ticarcillin and sulbactam combined with ampicillin resulted in synergistic activity against all beta-lactamase-positive organisms . Ceftizoxime was the most active of the cephalosporins . Two percent of the isolates were resistant to chloramphenicol and metronidazole . Clindamycin resistance was detected in 38% of the B . fragilis group, which is a marked increase from the 4% detected 10 years ago at this institution.

J Antimicrob Chemother, 1988 Mar, 21(3), 355 - 63
Metronidazole and gentamicin prophylaxis in synergistic aerobe-anaerobe infections in mice; Kelly MJ et al.; The efficacy of prophylaxis by intraperitoneal injection of gentamicin, metronidazole or both drugs combined was investigated in a mouse model of mixed infection with Escherichia coli and Bacteroides fragilis . A three dose prophylactic regimen given 12 hourly was studied starting simultaneously with bacterial challenge . Serum antibiotic concentrations lay within the human therapeutic ranges . Metronidazole alone eliminated B . fragilis from the developing infections, but at higher challenge doses the mice developed abscesses which contained E . coli, and mortality was no different from controls . Gentamicin alone eliminated both bacteria and deaths in all infections, but sterile abscesses occurred in two of five animals at the highest challenge dose . Mixed metronidazole + gentamicin abolished all effects of the challenge bacteria, aborting all infections for all challenge doses with no formation of sterile abscesses . It is proposed that, in abdominal surgery, although metronidazole or gentamicin may be effective given alone for low levels of contamination, for higher levels (e.g . colonic surgery) both drugs may be required.

J Bacteriol, 1988 Mar, 170(3), 1319 - 24
Mobilization of Bacteroides plasmids by Bacteroides conjugal elements; Valentine PJ et al.; A 4.2-kilobase cryptic Bacteroides plasmid, pB8-51, is found in several colonic Bacteroides species . To determine whether pB8-51 is mobilized by any of the known Bacteroides conjugal elements, we constructed an Escherichia coli-Bacteroides shuttle vector, pVAL-1, which contains pB8-51 . We constructed Bacteroides uniformis 0061 derivatives which carry pVAL-1 and various Bacteroides conjugal elements . The Bacteroides conjugal elements tested were six conjugal tetracycline resistance (Tcr) elements (which appear to be chromosomal), i.e., Tcr ERL, Tcr V479, Tcr Emr ERL, Tcr Emr 12256, Tcr Emr DOT, and Tcr Emr CEST, and the conjugal erythromycin resistance (Emr) plasmid pBF4 . These Tcr conjugal elements have not been extensively characterized, except for Tcr ERL . All six Tcr elements tested mobilized pVAL-1 at high frequency (10(-3) to 10(-5)) from one Bacteroides strain to another or from a Bacteroides strain to E . coli . Pregrowth of the donors (containing one of the Tcr elements and pVAL-1) in 1 microgram of tetracycline per ml enhanced the transfer of pVAL-1 by 20- to 10,000-fold, depending on which Tcr element was present in the donor . An Ems derivative of pBF4 (pBF4 delta E2) mobilized pVAL-1 from one Bacteroides strain to another at a frequency of 10(-4) but did not mobilize pVAL-1 from a Bacteroides strain to E . coli as efficiently . Thus the Tcr conjugal elements and pBF4 recognize a mobilization region on pB8-51.

Br J Obstet Gynaecol, 1988 Mar, 95(3), 286 - 93
Amoxycillin-clavulanic acid (Augmentin) versus metronidazole as prophylaxis in hysterectomy: a prospective, randomized clinical trial; Brown EM et al.; In order to determine the most effective regimen for the prevention of infection after elective hysterectomy, 300 patients were randomly assigned to receive three perioperative doses of either amoxycillin-clavulanic acid (1.2 g intravenous) or metronidazole (1 g suppository) . Of the 280 patients who were assessable 138 were given amoxycillin-clavulanic acid and 142 received metronidazole; 268 underwent abdominal hysterectomy and 12 had vaginal hysterectomy . Patients in the amoxycillin-clavulanic acid group had significantly less infectious morbidity (13.8%) than those in the metronidazole group (33.1%) . There were also statistically significant differences in favour of amoxycillin-clavulanic acid with respect to operative site infection, duration of hospital stay, need for postoperative antimicrobials, and surgery for operative site infection . But for one isolate of Bacteroides fragilis, all pathogens isolated from wound infections in the metronidazole group were aerobes . No anaerobes were isolated from patients in the amoxycillin-clavulanic acid group . The results suggest that prophylaxis for hysterectomy should consist of an agent, or combination of agents, with activity against both aerobic and anaerobic bacteria . Amoxycillin-clavulanic acid fulfils this criterion and appears to be effective and safe.

J Clin Microbiol, 1988 Mar, 26(3), 448 - 52
Detection of Bacteroides fragilis, Bacteroides thetaiotaomicron, and Bacteroides ovatus in clinical specimens by immunofluorescence with a monoclonal antibody to B . fragilis lipopolysaccharide; Viljanen MK et al.; A total of 1,897 clinical specimens (1,019 aspirates and 876 swabs) were studied by indirect immunofluorescence (IF) with a mouse monoclonal antibody (MAb) against a D-galactose oligomer of Bacteroides fragilis lipopolysaccharide . The MAb has been shown to react with 96% of clinical B . fragilis isolates and with about 50% of Bacteroides ovatus and Bacteroides thetaiotaomicron isolates but not with other aerobic or anaerobic organisms tested . The sensitivity of IF in comparison with culturing was 78.9% for all three species . Of the 32 strains originating from culture-positive, IF-negative specimens, 13 lacked the target determinant for the MAb . Sensitivity was highest with specimens taken from the perineal area (87.1%) and lowest with those taken from undefined sites (56.6%) . Sensitivity was better with aspirates (86.8%) than with swabs (72.6%) . The specificity of IF was 95.6% for all of the material . Positive and negative predictive values were 51.1 and 98.0%, respectively . Neither long transportation times of specimens nor antimicrobial therapy seemed to correlate with the occurrence of IF-positive, culture-negative specimens . This study shows that a single MAb can be used to establish an IF assay that can complement isolation in the detection of these three members of the B . fragilis group.

J Clin Periodontol, 1988 Mar, 15(3), 145 - 55
The role of black-pigmented Bacteroides in human oral infections; van Winkelhoff AJ et al.; Today, 10 black-pigmented Bacteroides (BPB) species are recognized . The majority of these species can be isolated from the oral cavity . BPB species are involved in anaerobic infections of oral and non-oral sites . In the oral cavity, BPB species are associated with gingivitis, periodontitis, endodontal infections and odontogenic abscesses . Cultural studies suggest a specific role of the various BPB species in the different types of infection . Bacteroides gingivalis is closely correlated with destructive periodontitis in adults as well as in juveniles . Bacteroides intermedius seems to be less specific since it is found in gingivitis, periodontitis, endodontal infections and odontogenic abscesses . The recently described Bacteroides endodontalis is closely associated with endodontal infections and odontogenic abscesses of endodontal origin . There are indications that these periodontopathic BPB species are only present in the oral cavity of subjects suffering from periodontal breakdown, being absent on the mucosal surfaces of subjects without periodontal breakdown . BPB species associated with healthy oral conditions are Bacteroides melaninogenicus, Bacteroides denticola and Bacteroides loescheii . There are indications that these BPB species are part of the normal indigenous oral microflora . Many studies in the past have documented the pathogenic potential and virulence of BPB species . This virulence can be explained by the large numbers of virulence factors demonstrated in this group of micro-organisms . Among others, the proteolytic activity seems to be one of the most important features . Several artificial substrates as well as numerous biological proteins are degraded . These include anti-inflammatory proteins such as alpha-2-macroglobulin, alpha-1-antitrypsin, C3 and C5 complement factors and immunoglobulins . B . gingivalis is by far the most proteolytic species, followed by B . endodontalis . Like other bacteria, the lipopolysaccharide of B . gingivalis has shown to be active in bone resorption in vitro and is capable in stimulating interleukin-1 production in human peripheral monocytes . Based on the well documented association with periodontal disease and the possession of relevant virulence factors, BPB species must be considered as important micro-organisms in the etiology of oral infections . B . gingivalis seems to be the most pathogenic and virulent species.

J Gen Microbiol, 1988 Mar, 134 ( Pt 3), 575 - 84
Nucleotide sequence of the pilin gene of Bacteroides nodosus 340 (serogroup D) and implications for the relatedness of serogroups; Finney KG et al.; The gene encoding pilin of Bacteroides nodosus 340 has been isolated and the nucleotide sequence determined . The gene is present as a single copy within the B . nodosus genome and a protein of Mr 16683 can be predicted from the proposed coding region . A comparison of the predicted amino acid sequence with pilin from other strains of B . nodosus indicated that the protein of strain 340 (serogroup D) has a high degree of similarity with pilin of strain 265 (serogroup H) . The degree of similarity between pilins from these strains and from other B . nodosus serogroups is no greater than that between B . nodosus pilins and the homologous proteins of several different bacterial species . These findings suggest that serogroups D and H may form a subset of B . nodosus serogroups.

J Dent Res, 1988 Mar, 67(3), 548 - 53
Production and characterization of monoclonal antibodies against Bacteroides forsythus and Wolinella recta; Werner-Felmayer G et al.; Hybrid cell lines producing monoclonal antibodies against Bacteroides forsythus or Wolinella recta were generated by fusion of SP2/0 or FO myeloma cells with splenocytes from Balb/c mice immunized with formalinized cells of B . forsythus FDC 331 or W . recta D13a-g, respectively . Enzyme-linked immunosorbent assays and indirect immunofluorescence tests were used to analyze the distribution of the recognized antigens on a panel of 70 strains representing 35 taxa, most of which are members of the oral flora . All monoclonal antibodies--eight against B . forsythus and six against W . recta--proved specific for the immunizing species . Four of the monoclonal antibodies against W . recta recognized antigens expressed by only some of the tested W . recta strains, thus confirming the earlier noted antigenic heterogeneity of this species . Antibody binding patterns consistent with those previously described or distinct for new serogroups could not, however, be observed . Four of the eight anti-B . forsythus monoclonal antibodies bound to only two of the three tested B . forsythus strains . All the remaining monoclonal antibodies detected every strain tested of the respective species against which they were raised . Preliminary results indicated that several of these antibodies should be very useful for the direct identification and quantification of these organisms in subgingival plaque.

J Periodontol, 1988 Mar, 59(3), 184 - 9
Refractory periodontitis: mixed infection with Bacteroides gingivalis and other unusual Bacteroides species . A case report; Van Dyke TE et al.; Host immune response and the predominant subgingival microflora were evaluated in a 47-year-old male exhibiting severe, recurrent periodontitis . The patient's neutrophils were chemotactically elevated but other functions were within normal limits . Significantly, Bacteroides gingivalis and Bacteroides zoogleoformans constituted 80% of the cultivable microflora and total cell count in subgingival plaque . The remainder of the cultivable microbiota was comprised of Fusobacterium nucleatum and Haemophillis aprophillis . The present study provides additional evidence for an association between B . gingivalis and severe, recurrent periodontal disease.

Can J Surg, 1988 Mar, 31(2), 98 - 100
Prevention of intra-abdominal abscesses with fibrinolytic agents; Rosenthal GA et al.; Fibrin deposition during secondary peritonitis predisposes to abscess formation by protecting bacteria from host-defence mechanisms . To test the hypothesis that local fibrinolytic therapy can prevent the formation of intra-abdominal abscess, daily injections of the fibrinolytic enzymes trypsin and tissue plasminogen activator (t-PA) were administered intraperitoneally to Wistar rats inoculated intraperitoneally with infected fibrin clots . After 5 days, trypsin (1 mg/ml) had significantly (p less than 0.001) reduced abscess formation in animals inoculated with monomicrobial Bacteroides fragilis clots (20% versus 87%) or mixed Escherichia coli-B . fragilis clots (11% versus 91%) . Bacteroides fragilis abscesses were also completely prevented with t-PA (0.25 mg/ml) . The number of B . fragilis organisms present in residual abscesses in the trypsin-treated group was significantly (p less than 0.05) lower than in the control group (8.2 +/- 0.2, n = 7 versus 5.7 +/- 1.4, n = 4, log CFU/g abscess) . In-vitro studies demonstrated that trypsin had no bactericidal effect on B . fragilis, suggesting enhanced clearance of bacteria . From these studies it appears that controlled fibrinolysis at operation may be a useful adjunct to surgery and systemic antibiotics in preventing abscess formation postoperatively.

Can J Microbiol, 1988 Mar, 34(3), 352 - 7
The spectrum of Escherichia coli--Bacteroides fragilis pathogenic synergy in an intraabdominal infection model; Rotstein OD et al.; Pathogenic synergy between Escherichia coli and Bacteroides fragilis was investigated in an intraabdominal infection model . Defined inocula of E . coli and B . fragilis, alone or in combination, were enmeshed within a fibrin clot and surgically implanted into the peritoneal cavity of rats . A spectrum of bacterial synergy ranging from synergistic abscess formation to synergistic lethality was demonstrated using this model . The type of synergy exhibited was dependent upon the initial E . coli inoculum . When combined with B . fragilis, high inocula of E . coli (greater than 10(8) cfu/clot) produced synergistic lethality while low inocula (2 x 10(2) to 2 x 10(7) cfu/clot) resulted in synergistic abscess formation . With respect to abscess formation, there was reciprocal synergy between E . coli and B . fragilis . Abscesses resulting from mixed inocula were larger and had significantly higher numbers of E . coli and B . fragilis than abscesses initiated by monomicrobial inocula . These studies define a clinically relevant model of bacterial interactions in the setting of intraabdominal infection and suggest that conclusions drawn from experimental models of bacterial synergy should consider the type of model examined, the strains of bacteria studied, and the number of bacteria inoculated.

J Am Vet Med Assoc, 1988 Feb 15, 192(4), 512 - 5
Genetic-associated resistance to foot rot in selected Targhee sheep; Bulgin MS et al.; Three Targhee rams obtained from the Ohio Agricultural and Experimental Station had been identified as foot rot resistant on the basis of results of challenge exposure . In the first breeding trial, when rams were bred to 20 foot rot-susceptible ewes, the percentages of foot rot-resistant offspring from the 3 foot rot-resistant rams were 68, 82, and 100, compared with 55 and 60 for foot rot-resistant offspring from 2 known foot rot-susceptible rams . In the second year, the foot rot-resistant rams were mated with ewes of unknown foot rot status . The foot rot-resistant status of their lambs was compared with that of range-raised lambs whose parents' foot rot status was unknown . During the first year, challenge exposure to the disease consisted of confinement of the lambs in moist or wet pens with sheep affected with the naturally acquired disease . This protocol was repeated for lambs born during the second-year breeding trial . In addition, the right front foot of each lamb was inoculated with a broth culture of Bacteroides nodosus . During the second year, when data that included infected feet from all lambs were analyzed, 41% of the progeny of the foot rot-resistant rams and 17% of the offspring of parents of unknown foot rot status were unaffected by the disease . When the B nodosus-inoculated foot was not included in the analysis, however, 61% of the progeny of the foot rot-resistant rams and 29% of the others were unaffected . The resistance to foot rot undoubtedly is hereditary . The mechanism of resistance may be in the interdigital skin.(ABSTRACT TRUNCATED AT 250 WORDS)

Biochem J, 1988 Feb 15, 250(1), 9 - 13
500 MHz 1H n.m.r . of oligosaccharides of N-acetyl-lactosamine-type released from human erythrocyte glycopeptides by endo-beta-galactosidase; Hounsell EF et al.; 500 MHz 1H n.m.r . spectroscopy has been used in structural studies of three linear and five branched oligosaccharides of N-acetyl-lactosamine-type that were released from desialylated blood group O erythrocyte glycopeptides by treatment with the endo-beta-galactosidase of Bacteroides fragilis followed by reduction . The following oligosaccharide alditols were characterized: (formula; see book)

Appl Environ Microbiol, 1988 Feb, 54(2), 534 - 9
Use of a unique gene sequence as a probe to enumerate a strain of Bacteroides ruminicola introduced into the rumen; Attwood GT et al.; Cloned fragments of genomic DNA from the ruminal anaerobe Bacteroides ruminicola subsp . brevis B14 were isolated and used as hybridization probes to identify closely related bacterial species . One DNA fragment unique to strain B14 was tested to determine its sensitivity in detecting homologous sequences among total ruminal microbial DNA . In a DNA titration experiment, the probe was capable of detecting strain B14 sequences in vitro down to 0.1% of the total bacterial DNA present in a hybridization assay . There was no detectable signal for total ruminal bacterial DNA . The specificity of this DNA fragment was exploited to enumerate strain B14 in a fresh mixed suspension of ruminal bacteria in vitro and after inoculation of the strain into the rumen . In vitro strain B14 had a half-life of 9 h . However, following inoculation into the rumen there was a very rapid loss of the strain to below the detectable limit within 3 h . The half-life was less than 30 min . This loss was not due to ruminal dilution or to bacteriophage attack but was possibly the result of a specific bacteriocinlike activity present in the rumen and detectable in fresh ruminal fluid.

J R Soc Med, 1988 Feb, 81(2), 95 - 6
Are we using the correct dose of metronidazole in colorectal surgery?
Hobbiss JH, Carr ND, Schofield PF.
In a series of 20 patients undergoing elective colorectal surgery, 10 received an infusion of metronidazole 500 mg and 10 an infusion of 1500 mg commencing at the induction of anaesthesia . The concentrations of metronidazole in the plasma, rectus muscle and colon of the two groups during the course of the operation were compared . In those patients who received 1500 mg, the plasma and tissue concentrations were all well above the minimum inhibitory concentration (MIC) of metronidazole against Bacteroides fragilis . In those patients who received 500 mg, serum and tissue concentrations were at or only just above the MIC . It may be that 1500 mg would be a more effective dose of metronidazole for prophylactic use in colorectal surgery.

Arch Fr Pediatr, 1988 Feb, 45(2), 119 - 22
{Septicemia, portal thrombosis and congenital protein C deficiency}; Garnier JM et al.; The authors report a case of Bacteroides fragilis septicemia with left portal vein thrombosis secondary to a liver abscess discovered by ultrasonography . This thrombosis was in relation with hereditary protein C deficiency . The authors emphasize the importance of assaying for C protein along with the other physiological coagulation inhibitors in the child presenting with venous thrombosis.

J Clin Periodontol, 1988 Feb, 15(2), 85 - 93
Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans in human periodontal diseases; Slots J et al.; Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans seem to be major pathogens in advancing periodontitis in man . First, these organisms are recovered in higher prevalence and proportions from progressive periodontitis lesions than from quiescent periodontal sites . Second, antibody levels against B . gingivalis and A . actinomycetemcomitans are markedly elevated in serum and gingival crevice fluid of periodontitis patients compared to normal controls . Third, B . gingivalis and B . intermedius elaborate potent proteases and A . actinomycetemcomitans various noxious substances which have the potential to perturb important host defenses and to disintegrate key constituents of the periodontal tissues . Monitoring these bacteria in advanced periodontal lesions may greatly assist the assessment of treatment efficacy and risk of further periodontal breakdown.

J Clin Periodontol, 1988 Feb, 15(2), 116 - 22
Microbial succession in recolonizing deep periodontal pockets after a single course of supra- and subgingival debridement; van Winkelhoff AJ et al.; In the present study, the effect of supra and subgingival plaque debridement on the dynamics of the subgingival microflora in deep pockets was investigated . 8 adult periodontitis patients participated in the study . In each patient, 4 clinically diseased sites were investigated microbiologically by phase contrast microscopy for the determination of both the %s as well as the total numbers of spirochetes and motile rods and by anaerobic cultivation for the determination of the different black-pigmented Bacteroides species . After base-line examination, patients were treated by mechanical removal of supra- and subgingival plaque deposits . 2 and 8 weeks after treatment, clinical and microbiological parameters were re-evaluated . During the experimental period, no oral hygiene procedures were performed in order to achieve fast recolonization of the pockets . Treatment resulted in a significant reduction in probing pocket depth and gain of probing attachment . 2 weeks after treatment, no further improvements could be observed . A positive correlation was found between the reduction in probing pocket depth and decrease in Bacteroides gingivalis (P less than 0.009) and between gain in probing attachment and reduction in the % of B . gingivalis (P less than 0.009) . No correlation between these clinical parameters and B . intermedius, spirochetes or motile rods was apparent . An inverse relationship between B . gingivalis and B . intermedius was observed . We found that changes in %s of spirochetes and motile rods are not correlated with changes in total numbers of these bacterial groups . It was concluded that monitoring of %s of micro-organisms may not supply rational information on the microbiological conditions of the subgingival area.

Genitourin Med, 1988 Feb, 64(1), 10 - 3
The enigma of non-gonococcal urethritis: role for Bacteroides ureolyticus; Hawkins DA et al.; Although up to about half the cases of acute non-gonococcal urethritis (NGU) are caused by Chlamydia trachomatis organisms (chlamydiae) and a smaller, ill-defined, proportion probably by Ureaplasma urealyticum organisms (ureaplasmas), the aetiology of all cases is not understood . Clarification of the role of the anaerobe, Bacteroides ureolyticus, was sought in the current study . Seventy five chlamydia negative patients with NGU were treated on a double blind placebo controlled basis with metronidazole . After seven days more of the 35 patients given this drug tended to improve clinically than the 40 given the placebo, but the difference was not significant . Of 23 chlamydia negative but anaerobe positive men, however, 78% (7/9) receiving metronidazole responded clinically, but only 7% (1/14) receiving placebo responded (p less than 0.001) . Furthermore, whereas 78% of the anaerobe positive men given metronidazole recovered, only 23% (6/26) of the anaerobe negative men did so (p less than 0.02) . No further evidence for the role of ureaplasmas in the aetiology of NGU was obtained, but the data suggest that B ureolyticus organisms, and perhaps other anaerobes, have an important role in a small proportion of cases and that the beneficial effects of metronidazole given on an empirical basis will be confined to anaerobe positive urethritis.

Biochemistry, 1988 Jan 26, 27(2), 625 - 33
Investigations of the partial reactions catalyzed by pyruvate phosphate dikinase; Wang HC et al.; The kinetic mechanism of pyruvate phosphate dikinase (PPDK) from Bacteroides symbiosus was investigated with several different kinetic diagnostics . Initial velocity patterns were intersecting for AMP/PPi and ATP/Pi substrate pairs and parallel for all other substrate pairs . PPDK was shown to catalyze {14C}pyruvate in equilibrium phosphoenolpyruvate (PEP) exchange in the absence of cosubstrates, {14C}AMP in equilibrium ATP exchange in the presence of Pi/PPi but not in their absence, and {32P}Pi in equilibrium PPi exchange in the presence of ATP/AMP but not in their absence . The enzyme was also shown, by using {alpha beta-18O, beta, beta-18O2}ATP and {beta gamma-18O, gamma, gamma, gamma-18O3}ATP and 31P NMR techniques, to catalyze exchange in ATP between the alpha beta-bridge oxygen and the alpha-P nonbridge oxygen and also between the beta gamma-bridge oxygen and the beta-P nonbridge oxygen . The exchanges were catalyzed by PPDK in the presence of Pi but not in its absence . These results were interpreted to support a bi(ATP,Pi) bi(AMP,PPi) uni(pyruvate) uni(PEP) mechanism . AMP and Pi binding order was examined by carrying out dead-end inhibition studies . The dead-end inhibitor adenosine 5'-monophosphorothioate (AMPS) was found to be competitive vs AMP, noncompetitive vs PPi, and uncompetitive vs PEP . The dead-end inhibitor imidodiphosphate (PNP) was found to be competitive vs PPi, uncompetitive vs AMP, and uncompetitive vs PEP . These results showed that AMP binds before PPi . The ATP and Pi binding order was studied by carrying out inhibition, positional isotope exchange, and alternate substrate studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagn Microbiol Infect Dis, 1988 Jan, 9(1), 47 - 50
Effect of clavulanic acid on the susceptibility of clinical anaerobic bacteria to ticarcillin: a multicenter study; Fuchs PC et al.; Over 2,000 recent clinical isolates of anaerobic bacteria were tested at five medical centers for susceptibility to ticarcillin, ticarcillin plus clavulanic acid, clindamycin, and metronidazole . At 64 micrograms/ml, ticarcillin inhibited 92% of all isolates, but 98% were inhibited at this concentration when 2 micrograms/ml of clavulanic acid was added . With different Bacteroides species, clavulanic acid reduced ticarcillin MICs 2- to 32-fold; other anaerobic species were not significantly affected.

Microbios, 1988, 53(214), 21 - 5
Diagnostic value of a coagglutination procedure using monoclonal antibodies to Bacteroides gingivalis; Shklair IL et al.; A specific monoclonal antibody against Bacteroides gingivalis was bound to particles coated with protein A and evaluated for use in a coagglutination test . B . gingivalis was the only organism tested which gave a specific positive reaction with the CoA reagent . Subgingival plaque samples were collected from 217 patients diagnosed as having periodontitis . Organisms that gave biochemical reactions which indicated they were B . gingivalis were isolated from eleven of the 217 gingival pockets . These eleven strains were the only organisms which gave a positive reaction using the CoA test.

Science, 1988 Jan 1, 239(4835), 55 - 7
Implantation of Bacteroides gingivalis in nonhuman primates initiates progression of periodontitis; Holt SC et al.; Although periodontitis is a bacterial disease, its multidimensional nature and its bacterial complexity have made it difficult to definitively prove that specific microorganisms initiate the disease process . The successful implantation of a rifampin-resistant strain of the putative periodontal pathogen Bacteroides gingivalis into the periodontal microbiota of monkeys (Macaca fascicularis) resulted in an increase in the systemic levels of antibody to the microorganism and rapid and significant bone loss.

Rev Infect Dis, 1988 Jan-Feb, 10(1), 76 - 91
Cefoxitin: its role in treatment and prophylaxis of obstetric and gynecologic infections; Counts GW; Cefoxitin has become one of the most used parenteral antibiotics in the United States, perhaps because of a broad spectrum of activity, including activity against Bacteroides fragilis, which makes the drug suitable for prevention and treatment of intraabdominal and pelvic infections . This review focuses on the use of cefoxitin in obstetric and gynecologic infections, with comparisons to older and newer antibiotics . Numerous studies have shown that cefoxitin is clearly effective; in most of these studies, however, either the initial infection rates were low or the sample sizes were small--circumstances making it difficult to establish the superiority of any one agent . Thus, the necessity of using a drug with activity against B . fragilis for prevention and treatment of pelvic infections has not been proven . Several antibiotics without such activity have been equally effective . Cefoxitin may be of particular value when combined with surgical drainage of pelvic abscesses, infections in which control of B . fragilis may be especially important to outcome.

Arch Oral Biol, 1988, 33(8), 547 - 53
The effect of the outer membrane fraction of Bacteroides gingivalis W50 on glycosaminoglycan metabolism by human gingival fibroblasts in culture; Smalley JW et al.; The synthesis of extracellular {35S}-SO4- and {3H}-glucosamine-labelled glycosaminoglycan (GAG) was studied in confluent human gingival fibroblast cultures in vitro . The differential synthesis of the total chondroitin sulphate/dermatan sulphate (CS/DS) and heparan-sulphate (HS) fraction was measured following chondroitinase-ABC digestion, nitrous-acid treatment and column chromatography on Sephadex G50 . Control cultures synthesized a CS/DS fraction that represented 78 per cent of the total {35S}-SO4-GAG; the residual 22 per cent was heparan sulphate . Similar cultures were labelled with {3H}-glucosamine and the proportions of a high molecular-weight hyaluronic acid (HA) and proteoglycan fractions measured by gel-filtration HPLC after papain and hyaluronidase digestions . The HA fraction represented 66 per cent of the total isotope incorporated in control cultures . GAG chains released on treatment with papain (24 per cent of the total label incorporated) were of apparent molecular weight 17-20 kDa . All cultures exposed to Bacteroides gingivalis W50 outer membrane at concentrations between 2 and 50 micrograms ml-1 displayed a decrease in the CS/DS fraction and a reciprocal increase in the HS . However, the proportion of HA synthesized was slightly enhanced with a reciprocal decrease in the proteoglycan (papain-digestible) fraction . There was no alteration in the molecular weight of the papain-digestion products or the size distribution of the hyaluronic-acid fraction.

Arch Gynecol Obstet, 1988, 244(1), 1 - 6
Preterm labor and bacterial intra-amniotic infection: arachidonic acid liberation by the action of phospholipase A2; Takahashi K et al.; There is a strong association between preterm labor and infection, presumably through an increase in prostaglandin (PG) formation . The studies presented in this report were undertaken to evaluate whether bacterial products stimulate endogenous phospholipid hydrolysis and arachidonic acid liberation by the action of phospholipase A2, a rate-limiting step for PG synthesis . When human endometrial cells prelabelled with {3H}arachidonic acid to an isotopically steady state were exposed to a medium conditioned with Bacteroides fragilis, arachidonic acid liberation was stimulated, accompanied with lysophospholipid formation . Similar stimulatory effect on phospholipid degradation was also observed in the experiments with the bacterial extract . These results demonstrate that the organism produces phospholipase A2 acting on endogenous phospholipids and/or factor(s) activating phospholipase A2 . Phospholipase A2 is suggested as a mechanism for the onset of labor associated with intra-amniotic infection and arachidonic acid liberation.

Microbios, 1988, 55(222), 17 - 24
The effect of human bile on Bacteroides fragilis in health and disease; Thadepalli H et al.; Bacteroides fragilis is generally believed to be stimulated by bile . Although B . fragilis is rarely found in the human duodenum, it is relatively frequent in gall bladder infections . To investigate this paradox, the growth of B . fragilis in the human bile in both health and disease was studied, and compared with the effect of bovine and porcine bile . B . fragilis was stimulated by the bovine bile and inhibited by the porcine bile . The normal human bile was either bacteriostatic or inhibitory whereas bile from cholelithiatic patients, in 50% of cases, stimulated the growth of B . fragilis . This explains the relative prevalence of B . fragilis in cholelithiatic cholecystitis patients although it is not a resident flora of the duodenum.

Arch Oral Biol, 1988, 33(5), 323 - 9
The degradation of type I collagen and human plasma fibronectin by the trypsin-like enzyme and extracellular membrane vesicles of Bacteroides gingivalis W50; Smalley JW et al.; A soluble trypsin-like enzyme (STE) was purified from a cell- and particle-free culture supernatant of this bacterium by a combination of ultra-centrifugation, ammonium-sulphate precipitation and gel-filtration chromatography on Sephacryl S-200 . Trypsin-like activity in the culture supernatant was associated with a 58 kDa peptide and also with a higher molecular-weight complex . The STE and extracellular vesicle (ECV) fraction of B . gingivalis W50 rapidly degraded human plasma fibronectin in the presence and the absence of 10 mM dithiothreitol (DTT) . The STE yielded a range of lower molecular-weight fibronectin digestion products . Under conditions where little activity was expressed by mammalian trypsin, both STE and ECV depolymerized a denatured and a native type I collagen substrate . Quantitative and qualitative differences were observed in the patterns of digestion products generated by both STE and ECV fraction following incubation with and without 10mM DTT . Inclusion of DTT appeared to reduce the degradative effect of both ECV and STE towards the type I collagen and plasma fibronectin substrates.

Scand J Infect Dis, 1988, 20(2), 187 - 92
Bacteriology of odontogenic apical periodontitis and effect of penicillin treatment; Ranta H et al.; The microbiology and treatment of apical periodontitis was studied in 62 patients, followed-up for 1 year . The clinical treatment and the radiological technique were standardized . One third of the patients received no systemic antibiotics, one third received phenoxymethylpenicillin for 1 week, and one third for 3 months . On the average, 0-2 facultatively anaerobic and 4-6 anaerobic bacteria were isolated from periapical infections . The genera Bacteroides and Fusobacterium in addition to anaerobic gram-positive cocci were found most frequently . Minimum inhibitory concentrations of benzylpenicillin against 269 strains were tested . 12 strains were resistant at the concentration 2.4 micrograms/ml, including 4 strains of Fusobacterium sp . All patients were free of symptoms 1 month after the admission . Only 1 patient failed to show any progress in radiological healing . No differences between the groups in relation to penicillin therapy were found.

J Antimicrob Chemother, 1988 Jan, 21(1), 17 - 26
A tissue culture model for study of growth promotion and antimicrobial susceptibility in Bacteroides fragilis; Claesson BE et al.; A new model for testing the susceptibility of anaerobic bacteria under in-vivo oxygen pressure is described . Bacteroides fragilis was incubated with a monolayer of mouse fibroblasts or with Escherichia coli or with both in tissue culture medium exposed to an aerobic atmosphere with 5% CO2 . B . fragilis started to multiply when the oxygen pressure of the medium was approximately 13 kPa . The resulting growth curves were similar whichever promoter was used . However, the reduction of the medium took place much earlier in the presence of E . coli . This may explain the excellent effect of metronidazole on B . fragilis in the E . coli combinations and its solely bacteriostatic effect in the plain tissue culture . Imipenem exerted a bactericidal effect in all systems and was the most potent agent tested.

Scand J Infect Dis Suppl, 1988, 57, 55 - 64
Antimicrobial resistance in oral and colonic bacteroides; Crook DW et al.; Antimicrobial resistance in Bacteroides from oral and colonic flora influences the selection of antimicrobial therapy to treat infections involving these organisms . An antimicrobial susceptibility study of 49 clinical isolates of oral bacteroides to 9 drugs revealed high resistance rates for penicillin 53%, for cefaclor 45%, and for tetracycline 27%, while there were low rates (less than 10%) with cefoxitin, piperacillin, clindamycin, chloramphenicol and metronidazole . Review of our U.S . nationwide survey of the susceptibility of colonic bacteroides (Bacteroides fragilis group) reveals low resistance to clindamycin, cefoxitin, piperacillin, imipenem, chloramphenicol and metronidazole . However, the identification of clindamycin, clindamycin, cefoxitin, piperacillin, imipenem and chloramphenicol resistant isolates is worrisome . The mechanism of resistance and the resistant transfer mechanism to the different classes of drugs in the oral and colonic bacteroides are reviewed.

Scand J Infect Dis Suppl, 1988, 57, 50 - 4
Beta-lactamase producing anaerobic bacteria in the oropharynx and their clinical relevance; Nord CE et al.; The mechanisms of resistance to beta-lactam antibiotics in anaerobic bacteria are production of beta-lactamases, alteration of penicillin-binding proteins and blocked penetration of beta-lactam agents through the outer membranes . The most important factor in beta-lactam resistance is production of beta-lactamase . Beta-lactamases have been found in oropharyngeal strains of bacteroides and fusobacteria isolated from orofacial infections, peritonsillitis and recurrent tonsillitis . Clinical failures with penicillin therapy of these infections are reported in an increasing frequency and other antimicrobial agents such as clindamycin and metronidazole should be considered in the treatment of these failures.

Eur Surg Res, 1988, 20(5-6), 304 - 9
Myoelectric activity of the small bowel in mechanical obstruction and intra-abdominal bacterial contamination; Lausen M et al.; The myoelectric activity of the small bowel was evaluated in 6 rabbits following 24 h of complete small-bowel obstruction and in 6 rabbits during an intra-abdominal perfusion with a bacterial suspension containing Bacteroides fragilis and Escherichia coli . Myoelectric recordings were performed before and during pharmacological small-bowel stimulation with ceruletide . Following small-bowel obstruction both slow-wave frequency and spike activity were reduced . Ceruletide stimulation demonstrated a significantly decreased spike activity after 24 h of obstruction . Intra-abdominal bacterial contamination did not affect spontaneous slow-wave frequency and spike activity but induced complete resistance to ceruletide stimulation . Pharmacological stimulation is recommended as an additional method to evaluate the impairment of myoelectric activity in motility disorders.

J Gen Microbiol, 1988 Jan, 134 ( Pt 1), 19 - 27
Studies on the proteolytic activity of Bacteroides fragilis; Gibson SA et al.; The proteolytic activity of the intestinal bacterium Bacteroides fragilis NCDO 2217 was cell-bound during exponential growth, but was progressively released from the cells in stationary phase . Proteins hydrolysed included casein, trypsin, chymotrypsin, azocasein and the proteins in azosoya bean flour . Collagen, azocoll, elastin, gelatin, ovalbumin and bovine serum albumin were either weakly degraded or completely refractory to proteolysis . Arylamidase activity was exhibited against leucine p-nitroanilide (LPNA), leucine beta-naphthylamide, glycyl-proline p-nitroanilide and valyl-alanine p-nitroanilide . The bacterium grew with ammonia, peptone or casein as sole nitrogen source . Azocasein- and LPNA-hydrolysing activities were consistently higher when grown on casein . Cell-bound protease activity increased concomitantly with growth rate in both carbon- and nitrogen-limited continuous culture . Leucine arylamidase activity was also growth-rate-dependent, being 3-fold greater at D = 0.18 h-1 compared to D = 0.03 h-1 . Extracellular proteolytic activity was only detected at low growth rates, accounting for about 25% of total protease activity.

Scand J Infect Dis Suppl, 1988, 53, 35 - 45
Antimicrobial agents in the treatment of periodontal diseases: special aspects on tetracycline and doxycycline; Heimdahl A et al.; Increasing evidence for the involvement of specific microorganisms in the etiology of human periodontal diseases has appeared during the last few years . The microorganisms most likely to cause periodontal disease are Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, Bacteroides intermedius and Capnocytophaga species . Many of the strains are resistant to tetracycline and doxycycline . Recently penicillin-resistant B . gingivalis and B . intermedius have also been described . A . actinomycetemcomitans strains and capnocytophaga strains are sensitive to tetracycline and doxycycline . This has raised the question if periodontal diseases are possible to treat with antimicrobial agents alone or in combination with scaling of the teeth and surgery . Although numerous studies with different antimicrobial agents have been published it is still controversial if antimicrobials agents have a role in the treatment of human periodontal diseases . Comparative randomized long term studies are still needed to answer this question.

Phlebologie, 1988 Jan-Mar, 41(1), 13 - 20
{Therapeutic possibilities for the diabetic and ischemic foot}; Leguit P et al.; The prognosis and treatment of a diabetic foot depend on the extent of the lesions . If infected, these lesions are always mixed, secondary to aerobic and anaerobic bacteroides . The antibiotic treatment must be well adjusted and applied for a long enough time . It is absolutely necessary, for the treatment to be effective, to know the level of the ischemia in order to decide whether a lesion or an amputation scar will heal without revascularization . The author discusses various non-invasive examinations . Today, distal revascularization if possible due to new surgical techniques . But, one must emphasize that the patency of an adequate by-pass is definitely longer than the survival of a diabetic patient, in general . A accurate diagnosis and a multiudiscipline treatment will therefore improve the quality of the survival of the patient.

Arch Oral Biol, 1988, 33(7), 479 - 85
Specific inhibition of adherence of an oral strain of Bacteroides gingivalis 381 to epithelial cells by monoclonal antibodies against the bacterial fimbriae; Isogai H et al.; Monoclonal antibodies against purified fimbriae from this organism blocked its adherence to buccal epithelial cells . Three clones of monoclonal antibodies against these fimbriae were selected for use . The isotype of the three was IgG1 kappa chain . The antibodies reacted with fimbriae or their partially dissociated oligomers, but not with their constituent monomers (43 K protein, fimbrilin) or with other B . gingivalis 381 components, in an enzyme-linked immunosorbent assay or by immuno-blotting . The antibodies agglutinated only B . gingivalis 381 cells and no other species of Bacteroides . The purified immunoglobulin G (IgG) antibodies inhibited bacterial adherence to the human buccal epithelial cells, but had no effect on bacterial haemagglutination to various animal and human erythrocytes . The papain-cleaved Fab fragment, which did not allow cell to cell cross-linking, also inhibited adherence of B . gingivalis 381 but did not interfere with haemagglutination . Thus the fimbriae of B . gingivalis 381 may be responsible for adherence to epithelial cells, which supports the notion that a different type of fimbria or a lectin-like protein may be acting as haemagglutinin in this bacterium.

Infect Immun, 1988 Jan, 56(1), 272 - 4
Bacteroides gingivalis fimbriae stimulate production of thymocyte-activating factor by human gingival fibroblasts; Hanazawa S et al.; In a previous report (Y . Ohmori, S . Hanazawa, S . Amano, T . Miyoshi, K . Hirose, and S . Kitano, infect . Immun . 55:947-954, 1987), we showed that human gingival fibroblasts spontaneously produce thymocyte-activating factor (FTAF), which stimulates mitogen-induced thymocyte proliferation . In the present study, we examined the effect of Bacteroides gingivalis fimbriae on FTAF production by the cells, because the fimbriae may be involved in attachment of the organism to periodontal tissues . We show here that the fimbriae bind to the cells, which may subsequently lead to the stimulation of FTAF production by the cells.

J Bacteriol, 1988 Jan, 170(1), 449 - 51
Direct repeats flanking the Bacteroides transposon Tn4351 are insertion sequence elements; Hwa V et al.; The clindamycin-erythromycin resistance (Ccr Emr) region of the Bacteroides transposon Tn4351 is flanked by direct repeats . This study showed that the direct repeats are insertion sequence (IS) elements . Although both IS elements can mediate transfer of the chloramphenicol (Cmr) marker on pBR328 by cointegrate formation with the conjugal IncW plasmid R388, IS4351R-mediated transfer of Cmr occurred at a consistently lower frequency than did the transfer mediated by IS4351L . Analysis of plasmids from the resultant transconjugants revealed IS-mediated activities such as deletions, tandem duplication of IS4351L, and excision of IS4351R.

Pharm Weekbl Sci, 1987 Dec 11, 9 Suppl, S48 - 52
Long-term oral ciprofloxacin for infection prophylaxis in allogeneic bone marrow transplantation; de Witte T et al.; The efficacy of oral ciprofloxacin to prevent bacterial infections during the first three months after allogeneic bone marrow transplantation (BMT) was assessed prospectively . Twenty-three recipients of lymphocyte depleted marrow grafts received ciprofloxacin orally, 500 mg twice daily for 90 days after BMT . Nine patients had no infections during ciprofloxacin prophylaxis; in the remaining 14 patients 19 febrile episodes occurred . No infections could be attributed to Gram-negative rods nor to fungal micro-organisms on the basis of the micro-organisms isolated . One infection, a pneumonia due to Bacteroides melaninogenicus, proved to be fatal . Allergic skin reactions were observed in three patients, but neither hematological nor nephrological side-effects could be substantiated in patients who were treated concomitantly with cyclosporine . Prolonged administration of ciprofloxacin turned out to be safe and effective in preventing serious aerobic bacterial infections during the first three months after BMT.

J Clin Microbiol, 1987 Dec, 25(12), 2317 - 21
Antibiotic- and method-dependent variation in susceptibility testing results of Bacteroides fragilis group isolates; Aldridge KE et al.; The susceptibilities of 36 isolates of the Bacteroides fragilis group to ceftizoxime, cefoxitin, clindamycin, and metronidazole were determined by using the National Committee for Clinical Laboratory Standards agar dilution reference method and a broth microdilution method using anaerobe, brucella, Schaedler, and brain heart infusion broths . MICs that were greater than or equal to fourfold higher or lower than those of the reference method were considered significant . Major and minor discrepancies in susceptibility interpretation (SI) were also noted . Ceftizoxime showed the greatest number of variations and SI discrepancies . In 72% of the cases, MICs in broth were greater than or equal to fourfold lower than those obtained by the reference method, resulting in 33% of the major and 22% of the minor discrepancies in SI . A total of 53% of the isolates were resistant to ceftizoxime by the reference method, but only 11 to 17% were resistant in the various broths . Significant variations in MICs of cefoxitin occurred in 19 to 22% of the isolates; 17 to 19% of the isolates showed major discrepancies and 31 to 58% showed minor discrepancies in SI . A total of 58% of the isolates were resistant to cefoxitin by the reference method, but only 19 to 28% were resistant in the various broths . Significant variations with clindamycin in broths ranged from 32 to 53% and resulted in 3 to 8% of the isolates showing major discrepancies and 33 to 44% showing minor discrepancies in SI . Metronidazole yielded significant variations in MICs in 6 to 28% of the isolates, but no major or minor SI discrepancies were noted . This study indicates that significant differences in susceptibility results, which appear to be method related, can result when isolates of the B . fragilis group are tested . Therefore, studies correlating in vitro results, determined by various methods, to clinical outcome are essential.

Antimicrob Agents Chemother, 1987 Dec, 31(12), 2002 - 4
Activity of newer beta-lactam agents against clinical isolates of Bacteroides fragilis and other Bacteroides species; O'Keefe JP et al.; The in vitro activities of beta-lactam antibiotics against Bacteroides fragilis and B . fragilis group isolates are presented . Clinical isolates from 1986 were compared with strains from 1979 to 1982 . Imipenem, ticarcillin-clavulanic acid, and ceftizoxime were the most active agents . Cefotetan was equivalent to cefoxitin against B . fragilis but less active against B . fragilis group isolates . Enhancement of cefotaxime by its desacetyl metabolite was minimal.

Antimicrob Agents Chemother, 1987 Dec, 31(12), 1915 - 8
Subinhibitory concentrations of tetracycline alter fibrinogen binding by Bacteroides intermedius; Lantz MS et al.; Previous studies from our laboratory have shown that a strain of Bacteroides intermedius, VPI 8944, an organism isolated originally from a patient with acute necrotizing ulcerative gingivitis, binds human fibrinogen rapidly, reversibly, specifically, saturably, and with high affinity (M.S . Lantz, L.M . Switalski, K.S . Kornman, and M . Hook, J . Bacteriol . 163:623-628, 1985) . We examined the effect of growth in subinhibitory levels (sub-MICs) of tetracycline on fibrinogen binding by these bacteria and found concentration-dependent inhibition of fibrinogen binding by bacteria grown in the presence of tetracycline over the range of tetracycline concentrations from 1/64 to 1/8 the MIC . Analysis of the binding data suggests that bacteria grown in the presence of sub-MICs of tetracycline bind fewer fibrinogen molecules per cell than do bacteria grown in the absence of the drug . If fibrinogen-mediated adherence is important in the establishment B . intermedius in periodontal lesions and lesions of acute necrotizing ulcerative gingivitis, then tetracycline may be effective in disrupting establishment of these organisms at concentrations well below those required to achieve a bacteriostatic effect.

J Clin Microbiol, 1987 Dec, 25(12), 2330 - 3
Isolation of enterotoxigenic Bacteroides fragilis from humans with diarrhea; Myers LL et al.; Enterotoxigenic Bacteroides fragilis was isolated from stool specimens of 8 of 44 diarrheic individuals (ages, 4 months to 69 years) . The individuals had watery diarrhea and intestinal cramping; and infants had hyperthermia, vomiting, and blood in the stools . No recognized enteric pathogens were detected in seven of the eight diarrheic individuals positive for enterotoxigenic B . fragilis . The bacterium produced an enterotoxin detectable in concentrated broth that supported bacterial growth . Fifteen adult rabbits with ligated ceca developed fatal enteric disease following intraileal injection with 5 x 10(9) CFU of enterotoxigenic B . fragilis . Conversely, eight control rabbits injected with nonenterotoxigenic B . fragilis remained clinically normal . As few as 5 x 10(3) CFU of enterotoxigenic B . fragilis caused fatal enteric disease in the rabbit model . Disease in rabbits was characterized by mucoid, often hemorrhagic, diarrhea . The bacterium colonized the caudal small intestine and the colon of the rabbits and caused moderate to severe necrotizing colitis . Enterotoxigenic B . fragilis is widespread in the intestinal tract of diarrheic humans and is enteropathogenic in adult rabbits with ligated ceca . Its possible role in the enteric disease complex merits further study.

J Periodontol, 1987 Dec, 58(12), 868 - 72
Rapidly progressive periodontitis . Neutrophil chemotaxis inhibitory factors associated with the presence of Bacteroides gingivalis in crevicular fluid; Di Murro C et al.; In the last few years several bacteriological and immunological studies have investigated the role of bacteria and immune defects in order to establish the etiopathogenesis of periodontal disease . With regard to the immune system, a defect in polymorphonuclear neutrophil (PMN) chemotaxis has been frequently reported in patients with rapidly progressive or juvenile periodontitis . The purpose of this study was to investigate in five patients with rapidly progressive periodontitis and normal chemotaxis of peripheral blood PMNs the presence of chemotaxis inhibitory activity in gingival fluid and to relate such activity to three types of bacteria, often involved in rapidly evolving periodontal lesions, that are able to inhibit in vitro PMN chemotaxis: Bacteroides gingivalis, Capnocytophaga sp., and Actinobacillus actinomycetemcomitans . We found strong inhibitory activity in three of these patients . This activity was consistently associated with the finding of B . gingivalis in gingival pockets . We cannot rule out, however, that other substances not of bacterial origin could be responsible for such inhibitory activity . The strict association with B . gingivalis, known to secrete blocking factors, is highly suggestive, although this data must be considered preliminary.

Infect Immun, 1987 Dec, 55(12), 3131 - 6
Isolation of a membrane-associated Bacteroides gingivalis glycylprolyl protease; Grenier D et al.; A low-molecular-weight proteolytic enzyme was purified 47-fold from outer membranes of Bacteroides gingivalis ATCC 33277 by preparative polyacrylamide gel electrophoresis . The enzyme was present in all B . gingivalis strains tested but was not found in other species of black-pigmented Bacteroides . The molecular weight, determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, was 19,500 when the enzyme was heated to 100 degrees C in SDS before electrophoresis and 29,000 when it was mixed with SDS but not heated . The optimum pH, with azocasein as the substrate, was between 6.0 and 6.5 . The activity was inhibited by phenylmethylsulfonyl fluoride, N-alpha-p-tosyl-L-lysine chloromethyl ketone, Hg2+, and various reducing agents . The enzyme was active against azocasein, azocoll, proline-rich protein from saliva, and the synthetic peptide glycyl-L-proline-p-nitroanilide . The enzyme did not degrade acid-soluble collagen nor did it hydrolyze various arginine- and lysine-containing synthetic substrates.

Appl Environ Microbiol, 1987 Dec, 53(12), 2849 - 53
Fermentation of xylans by Butyrivibrio fibrisolvens and other ruminal bacteria; Hespell RB et al.; The ability of Butyrivibrio fibrisolvens and other ruminal bacteria (6 species, 18 strains) to ferment a crude xylan from wheat straw or to ferment xylans from larchwood or oat spelts was studied . Liquid cultures were monitored for carbohydrate utilization, cell growth (protein), and fermentation acid production . B . fibrisolvens 49, H17c, AcTF2, and D1 grew almost as well on one or more of the xylans as they did on cellobiose-maltose . B . fibrisolvens 12, R28, A38, X10C34, ARD22a, and X6C61 exhibited moderate growth on xylans . Partial fermentation of xylans was observed with Bacteroides ruminicola B14, Bacteroides succinogenes S85, Ruminococcus albus 7, Ruminococcus flavefaciens C94 and FD1, and Succinivibrio dextrinosolvens 22B . All xylans tested appeared to have a small fraction of carbohydrate that supported low levels of growth of nonxylanolytic strains such as Selenomonas ruminantium HD4 . Compared to growth on hexoses, the same array of fermentation acids was produced upon growth on xylans for most strains; however, reduced lactate levels were observed for B . fibrisolvens 49 and Selenomonas ruminantium HD4 . Measurements of enzyme activities of B . fibrisolvens AcTF2, 49, H17c, and D1 indicated that the xylobiase activities were cell associated and that the xylanase activities were predominantly associated with the culture fluid . The pattern of expression of these enzymes varied both between strains and between the carbon sources on which the strains were grown.

Acta Pathol Microbiol Immunol Scand {C}, 1987 Dec, 95(6), 241 - 50
Effects of endotoxins from Bacteroides intermedius and Escherichia coli on human monocytes in vitro; Johne B et al.; Endotoxins (lipopolysaccharides, LPSs) from the strictly anaerobic bacterium Bacteroides intermedius and from Escherichia coli were compared with respect to effects on human monocytes . Exposure of monocyte monolayer cultures to the structurally different endotoxins caused morphological changes, demonstrated by large rounded cells containing cytoplasmic granules with the B . intermedius LPS, and smaller cells with several cytoplasmic protrusions with the E . coli LPS after 10 days of culture . The B . intermedius LPS was, at some doses, able to induce an increased level of the lysosomal enzyme acid phosphatase and increased C3b-receptor-mediated phagocytosis, while other doses gave no effect or weak suppression compared to control cultures . The stimulatory effects were donor-dependent . The E . coli LPS had predominantly suppressive effects on acid phosphatase level and C3b phagocytosis . Both endotoxins resulted in enhanced expression of the activation related cell surface antigen, characterized by the mononuclear phagocyte specific monoclonal antibody 1D5 . Biphasic dose-response relationships were observed, particularly pronounced with B . intermedius LPS, giving stimulation of enzyme activity with low (1 ng/ml) and high (0.5 microgram/ml) doses, and suppressed enzyme activity with intermediate doses (0.01-0.10 microgram/ml) . The results imply that the effects of endotoxins on different aspects of human monocytes vary considerably; they also suggest that the balance between stimulatory and suppressive properties of a particular endotoxin may influence its net effect on mononuclear phagocyte functions.

Am J Vet Res, 1987 Dec, 48(12), 1751 - 4
Efficacy of amoxicillin trihydrate for the treatment of experimentally induced foot rot in cattle; Braun RK et al.; Twenty holstein heifers were intradermally inoculated in the interdigital skin with a suspension containing Fusobacterium necrophorum and Bacteroides melaninogenicus to induce acute foot rot . Lesions, lameness, and swelling were evaluated during the study, using a subjective scoring system . Rectal temperature, species and number of bacteria isolated, and change in body weight were monitored throughout the study . Ten heifers (treated) were given amoxicillin trihydrate (10 mg/kg of body weight, IM) for 5 days, beginning at the onset of lameness . The remaining 10 heifers (controls) were given physiologic saline solution IM . Treated heifers had less severe lesions and greater weight gain than did control heifers . Rectal temperatures of treated heifers did not differ significantly from those of control heifers . It was concluded that administration of amoxicillin trihydrate early in the course of acute foot rot may reduce the severity of lesions associated with foot rot in cattle.

Presse Med, 1987 Nov 14, 16(38), 1889 - 90
{Mediastinitis caused by anaerobic bacteria . 4 cases}; Piperno D et al.; In 4 cases of mediastinitis caused by anaerobes and consecutive to dental abscess (2 cases), perforation of the oesophagus and tonsillar abscess, the diagnosis was based on widening of the mediastinum associated, in 2 cases, with pneumomediastinum . II all 4 cases, Bacteroides fragilis was present among other germs . Treatment consisted of surgical drainage by thoracotomy (2 cases), or cervicotomy and antibiotic therapy . Two of the patients, who were old and had underlying diseases, died.

Eur J Biochem, 1987 Nov 2, 168(3), 585 - 93
Characterisation of oligosaccharides released from human-blood-group O erythrocyte glycopeptides by the endo-beta-galactosidase of Bacteroides fragilis . A study of the enzyme susceptibility of branched poly(N-acetyllactosamine) structures; Scudder P et al.; Desialylated human blood group O erythrocyte glycopeptides were digested with the endo-beta-galactosidase of Bacteroides fragilis and the enzyme-released products reduced with NaBH4 and purified by Bio-Gel P-4 chromatography . Three linear and six branched oligosaccharides of poly(N-acetylllactosamine) type, which together accounted for 90% of the oligosaccharide alditols, were characterised by fast-atom-bombardment mass spectrometry and gas-liquid chromatography/mass spectrometry . Linkage and composition data were obtained for the remaining material . The salient findings were (a) the branched oligosaccharide alditols each contained the sequence: (Formula: see text) and (b) there was no evidence for the terminal branch-point sequence: (Formula: see text) . Together these observations indicate that, as with erythrocyte glycolipids described previously {Scudder, P., Hanfland, P., Uemura, K . & Feizi, T . (1984) J . Biol . Chem . 259, 6586-6592}, the endo-beta-galactosidase of Bacteroides fragilis cannot hydrolyse branch-point beta-galactosidic linkages on erythrocyte membrane glycopeptides.

Diagn Microbiol Infect Dis, 1987 Nov, 8(3), 157 - 63
Comparative antimicrobial activity of aminothiazolyl methoxyimino cephalosporins against anaerobic bacteria, including 100 cefoxitin-resistant isolates; Jones RN et al.; Three aminothiazolyl methoxyimino cephalosporins (ceftizoxime, ceftriaxone, and cefotaxime with and without its metabolite) were tested against 500 strains of anaerobic bacteria using the NCCLS reference agar dilution procedure . Eighty-seven percent of all strains tested were from the Bacteroides fragilis group . When tested against a collection of 100 cefoxitin-resistant isolates, ceftizoxime and the cefotaxime/desacetyl-cefotaxime combination were the most active in vitro, inhibiting 32-38% of strains . Ceftriaxone inhibited the greatest number (87%) of cefoxitin-susceptible anaerobes at less than or equal to 32 micrograms/ml . A regional variation in the activity of these drugs was confirmed when an additional 300 isolates were examined from three medical centers . Cefotaxime, ceftizoxime, and ceftriaxone were essentially equal in overall antimicrobial activity, although each drug was judged the best at one of the three locations . Cefoxitin resistance (MIC greater than or equal to 32 micrograms/ml) was consistent among the institutions at a 25% incidence for all organisms tested, and 28% cefoxitin resistance among the B . fragilis group strains . Cefoxitin resistance was not determined to be associated with a beta-lactamase mechanism, but ceftriaxone and other aminothiazolyl cephems were hydrolyzed, thus elevating their MICs . Regional variation in anaerobic organism susceptibility to cephamycins and cephalosporins in company with the variable beta-lactam resistance mechanisms seems to require periodic, epidemiologic monitoring of in vitro drug activity by appropriate methods to assure continued antimicrobial efficacy.

Antimicrob Agents Chemother, 1987 Nov, 31(11), 1739 - 43
Cryptic tetracycline resistance determinant (class F) from Bacteroides fragilis mediates resistance in Escherichia coli by actively reducing tetracycline accumulation; Park BH et al.; Escherichia coli bearing a cryptic tetracycline resistance determinant from Bacteroides fragilis expressed low-level constitutive resistance to tetracycline under aerobic, but not anaerobic, growth conditions and accumulated less tetracycline aerobically than did isogenic susceptible cells . This decreased uptake was energy dependent and reversible by increased concentrations of tetracycline, suggesting a saturable carrier-mediated active efflux mechanism . Decreased uptake was not seen when the cells were grown and assayed anaerobically . Other tetracycline resistance determinants (classes A to E) isolated from gram-negative enteric bacteria expressed resistance and generated active efflux of tetracycline under anaerobic as well as aerobic conditions . When the Bacteroides determinant was placed in the same cell with any of the class A to E tetracycline resistance determinants, there was an increase in resistance under aerobic conditions of as much as 48% more than was projected by adding the resistances expressed by the determinants individually . In cells bearing the class A determinant together with the Bacteroides determinant, saturation of the active efflux system required over twofold more exogenous tetracycline than did cells bearing the class A determinant alone . We have designated this new tetracycline resistance determinant class F.

Infect Immun, 1987 Oct, 55(10), 2534 - 7
Effect of immunization on experimental Bacteroides gingivalis infection in a murine model; Chen PB et al.; BALB/c mice were immunized with an invasive (A7A1-28) or noninvasive (381) Bacteroides gingivalis strain, Bacteroides intermedius, or Ringer solution . All immunized mice were subsequently challenged with the invasive B . gingivalis strain and examined for septicemia or secondary spread of the infection or both . Mice immunized with the invasive B . gingivalis strain localized the infection to the challenge site . Mice immunized with the noninvasive B . gingivalis strain, B . intermedius, or Ringer solution developed spreading infections . These data suggest that immunization with an invasive B . gingivalis strain can alter the course of subsequent infections.

Infect Immun, 1987 Oct, 55(10), 2391 - 7
Bacteroides gingivalis-Actinomyces viscosus cohesive interactions as measured by a quantitative binding assay; Schwarz S et al.; There is limited evidence, mostly indirect, to suggest that the adherence of Bacteroides gingivalis to teeth may be enhanced by the presence of gram-positive dental plaque bacteria like Actinomyces viscosus . The purpose of this study was to carry out direct quantitative assessments of the cohesion of B gingivalis and A . viscosus by using an in vitro assay modeled on the natural sequence in which these two species colonize the teeth . The assay allowed comparisons to be made of the adherence of 3H-labeled B . gingivalis 2561 and 381 to saliva-coated hydroxyapatite beads (S-HA) and A . viscosus WVU627- or T14V-coated S-HA (actinobeads) in equilibrium and kinetics binding studies . A series of preliminary binding studies with 3H-labeled A . viscosus and parallel studies by scanning electron microscopy with unlabeled A . viscosus were conducted to establish a protocol by which actinobeads suitable for subsequent Bacteroides adherence experiments could be prepared . By scanning electron microscopy, the actinobeads had only small gaps of exposed S-HA between essentially irreversibly bound A . viscosus cells . Furthermore, B . gingivalis cells appeared to bind preferentially to the Actinomyces cells instead of the exposed S-HA . B . gingivalis binding to both S-HA and actinobeads was saturable with at least 2 X 10(9) to 3 X 10(9) cells per ml, and equilibrium with saturating concentrations was reached within 10 to 20 min . B . gingivalis always bound in greater numbers to the actinobeads than to S-HA . These findings provide direct measurements supporting the concept that cohesion with dental plaque bacteria like A . viscosus may foster the establishment of B . gingivalis on teeth by enhancing its adherence.

Eur J Clin Microbiol, 1987 Oct, 6(5), 536 - 41
Bacterial vaginosis: microbiological and clinical findings; Holst E et al.; A prospective study was performed involving 101 women who consecutively attended a primary health care unit for complaints of genital malodour and/or abnormal vaginal discharge . Bacterial vaginosis was diagnosed in 34 women on the basis of four diagnostic criteria: vaginal pH greater than 4.7, homogeneous vaginal discharge, a positive amine test and clue cells . The sensitivity of these criteria was greater than 90% except for homogeneous discharge (82%) . Their specificity was greater than 90% except for vaginal pH greater than 4.7 (46%); a specificity of 87% could have been achieved by using the criterion for vaginal pH greater than or equal to 5.0 . There was a strong association between diagnosis of bacterial vaginosis and the concomitant occurrence of Gardnerella vaginalis, Mobiluncus spp . and Bacteroides spp . There was no difference between women with or without bacterial vaginosis as regards contraception methods (except for use of an intrauterine device), age at first intercourse, or earlier episodes of vaginal discharge . Sexual transmission of the predominant bacteria was not supported by data collected from the male consorts.

Antimicrob Agents Chemother, 1987 Oct, 31(10), 1596 - 9
Disk diffusion susceptibility testing of the Bacteroides fragilis group; Horn R et al.; The susceptibilities of 225 isolates of the Bacteroides fragilis group to six antibiotics were determined by a new disk diffusion test in Wilkins-Chalgren agar and by the standard agar dilution method . For disk diffusion, the bacteria were directly suspended in saline and immediately swabbed onto 15-cm agar plates . Disks of cefoxitin (30 micrograms), chloramphenicol (30 micrograms), clindamycin (2 micrograms), moxalactam (30 micrograms), imipenem (10 micrograms), and ticarcillin (75 micrograms) were applied, and the plates were incubated at 37 degrees C in an anaerobic atmosphere . Zone sizes were measured at 24 h . The results of disk diffusion and agar dilution were compared by regression analysis by the method of least squares and by the error rate-bounded method . Zones were easily measured for 216 strains (96%) . The correlation between the MICs and diameters of inhibition for cefoxitin, clindamycin, moxalactam, and ticarcillin was generally good . A correlation could not be established for chloramphenicol and imipenem, as there were too few resistant strains . With the recommended resistance breakpoints, the following susceptible and resistant zone diameter breakpoints could be established: cefoxitin, less than or equal to 19 and greater than or equal to 21 mm; clindamycin, less than or equal to 14 and greater than or equal to 18 mm; moxalactam, less than or equal to 21 and greater than or equal to 25 mm; and ticarcillin, less than or equal to 15 and greater than or equal to 16 mm . By applying these zone criteria, the percentage of false-susceptible strains was less than 1% and of false-resistant strains was less than 4% for the drugs tested.

Diagn Microbiol Infect Dis, 1987 Oct, 8(2), 87 - 94
Ceftizoxime and cefoxitin susceptibility testing against anaerobic bacteria: comparison of results from three NCCLS methods and quality control recommendations for the reference agar dilution procedure; Jones RN et al.; Ceftizoxime and cefoxitin (control) were tested against 99 anaerobic bacteria using three commonly used susceptibility testing methods . The cefoxitin MIC results with the National Committee for Clinical Laboratory Standards (NCCLS) reference agar dilution (RAD) method and the broth microdilution (BMD) method did not differ by more than one log2 dilution step . However, the ceftizoxime BMD MIC results were 2- to 4-fold lower than those produced by the RAD procedure . Broth disk elution (BDE) tests for both cephalosporins (ceftizoxime and cefoxitin) had very high rates of false-susceptible and false-resistant error when compared to the RAD MICs: the BDE tests are not recommended for either cephalosporin . Findings indicate that because of method and possible medium or technical variability, ceftizoxime MICs should be determined only by the NCCLS RAD method . Also, cefoxitin susceptibility should be assessed primarily by RAD or BMD procedures . This should minimize confusion related to ceftizoxime's spectrum and activity against anaerobic bacteria compared to similar beta-lactam drugs . Ceftizoxime quality control guidelines were established for Bacteroides fragilis (ATCC 25285): mode, 64 micrograms/ml, range 32-128 micrograms/ml . Other control strains were not reliable.

J Gen Microbiol, 1987 Oct, 133 ( Pt 10), 2883 - 94
Trypsin-like enzyme activity of the extracellular membrane vesicles of Bacteroides gingivalis W50; Smalley JW et al.; Trypsin-like enzyme activity in spent culture media from 3-d-old batch cultures of Bacteroides gingivalis W50 was measured by using the hydrolysis of N alpha-benzoyl-L-arginine-p-nitroanilide . The cell-free culture medium was fractionated by differential centrifugation at 10,000 g and 75,000 g, yielding two particulate fractions and a soluble supernatant fraction . About 80% of the total recoverable activity was associated with the particulate fractions, the remainder being in the supernatant . Electron microscopy of ruthenium-red/osmium stained ultrathin sections of the pellet fractions showed them to be composed of vesicular particles (extracellular vesicles), between 50 and 250 nm in diameter . Enzyme activity in all three fractions was enhanced by dithiothreitol . Gel-permeation chromatography of the soluble fraction yielded one peak of activity which contained 64 kDa and 58 kDa polypeptides . Enzyme activity from the vesicular fractions could be solubilized by sonication, giving a similar chromatographic profile to the supernatant fraction . The main peak of activity was composed of 64 kDa and 58 kDa polypeptides . In addition, there was a higher molecular mass enzyme activity peak composed of the 64 kDa and 58 kDa components along with 111 kDa, 93 kDa and 70 kDa polypeptides . We conclude that the trypsin-like enzyme of B . gingivalis is released as a soluble protein and is also associated with extracellular vesicles, in which it may exist as a soluble component and also as a protein complex.

J Gen Microbiol, 1987 Oct, 133 ( Pt 10), 2773 - 80
Regulation of synthesis and reversible inactivation in vivo of dual coenzyme-specific glutamate dehydrogenase in Bacteroides fragilis; Yamamoto I et al.; Regulation of the dual coenzyme-specific glutamate dehydrogenase (GDH; EC 1.4.1.3) was studied in the anaerobic bacterium Bacteroides fragilis . Cells grown at a low concentration of ammonia had a specific activity for the enzyme 10-fold higher than that for cells grown with excess ammonia . Immunochemical determination with a GDH-specific antiserum showed that the content of immuno-precipitated protein was about 8% of the total protein in the former cells and was 4% in the latter cells . When cells grown on 50 mM-NH4Cl were transferred to a fresh medium containing 0.5 mM-NH4Cl, an increase in the molecular activity of the enzyme occurred, and synthesis of immuno-reactive protein started . Rapid inactivation of the GDH occurred when cells grown on 1 mM-NH4Cl were exposed to 50 mM-NH4Cl . However, the amount of immuno-precipitated protein was not decreased . The inactivation was specifically induced by ammonia and was reversed by transferring the cells to an ammonia-limited medium even in the presence of chloramphenicol . These findings suggest that the synthesis of the GDH is stimulated under low ammonia conditions and that the enzyme activity is controlled by means of a reversible activation/inactivation mechanism which is regulated by ammonia . However, no phosphorylation of GDH was observed before and after exposure of cells to high concentrations of ammonia.

Appl Environ Microbiol, 1987 Oct, 53(10), 2588 - 9
Isolation of intact high-molecular-weight DNA by using guanidine isothiocyanate; Lippke JA et al.; A method for obtaining high-molecular-weight chromosomal DNA from Bacteroides intermedius and Bacteroides gingivalis is described . This technique is a modification of the guanidine isothiocyanate isolation procedure for RNA and should be useful for isolating intact DNA from organisms with high endogenous nuclease activity.

J Clin Periodontol, 1987 Oct, 14(9), 528 - 33
The effect of subgingival debridement with hand and ultrasonic instruments on the subgingival microflora; Oosterwaal PJ et al.; The effect of hand or ultrasonic instrumentation on the subgingival microflora of periodontal pockets was investigated . Pockets with probing depths of 6-9 mm were selected in 12 patients and were randomly assigned per patient to the experimental and control groups . After oral hygiene instruction, instrumentation of the experimental pockets was carried out either by ultrasonic or by hand instruments in a split-mouth design . The treatment effect on the subgingival microbiota was evaluated by microscopic and culture studies of subgingival plaque samples, while in addition, supragingival plaque, bleeding after probing and probing pocket depth were scored . Examinations were carried out before and 7, 21 and 49 days after treatment . The hand and ultrasonic treatments were equally effective in reducing probing pocket depths and bleeding scores . At the end of the experimental period, the probing depths of 54% of the hand-treated pockets and 43% of the ultrasonic-treated pockets were reduced to 4 mm or less while the bleeding scores were reduced to 29% and 22%, respectively . The analysis of microscopical and cultural data did not show any differences between hand and ultrasonic debridement . Both treatments reduced the microscopical counts of rods, spirochetes and motiles and reduced the total colony-forming units and number of black-pigmented Bacteroides and Capnocytophaga, resulting in a subgingival microbiota consistent with periodontal health.

Appl Environ Microbiol, 1987 Oct, 53(10), 2505 - 10
Regulation of beta-glucosidase in Bacteroides ruminicola by a different mechanism: growth rate-dependent derepression; Strobel HJ et al.; Bacteroides ruminicola B(1)4, a predominant ruminal and cecal bacterium, was grown in batch and continuous cultures, and beta-glucosidase activity was measured by following the hydrolysis of p-nitrophenyl-beta-glucopyranoside . Specific activity was high when the bacterium was grown in batch cultures containing cellobiose, mannose, or lactose (greater than 286 U/g of protein) . Activity was reduced approximately 90% when the organism was grown on glucose, sucrose, fructose, maltose, or arabinose . The specific activity of cells fermenting glucose was initially low but increased as glucose was depleted . When glucose was added to cultures growing on cellobiose, beta-glucosidase synthesis ceased immediately . Catabolite repression by glucose was not accompanied by diauxic growth and was not relieved by cyclic AMP . Since glucose-grown cultures eventually exhibited high beta-glucosidase activity, cellobiose was not needed as an inducer . Catabolite repression explained beta-glucosidase activity of batch cultures and high-dilution-rate chemostats where glucose accumulated, but it could not account for activity at slow dilution rates . Maximal beta-glucosidase activity was observed at a dilution rate of approximately 0.35 h-1, and cellobiose-limited chemostats showed a 15-fold decrease in activity as the dilution rate declined . An eightfold decline was observed in glucose-limited chemostats . Since inducer availability was not a confounding factor in glucose-limited chemostats, the growth rate-dependent derepression could not be explained by other mechanisms.

Appl Environ Microbiol, 1987 Oct, 53(10), 2379 - 83
Effect of extracellular pH on growth and proton motive force of Bacteroides succinogenes, a cellulolytic ruminal bacterium; Russell JB; The utilization of cellulose or cellobiose by Bacteroides succinogenes S85 was severely inhibited at pH values of less than 5.7 . Since low pH inhibited the utilization of both cellobiose and cellulose, changes in cellulase activity could not explain the effect . At an extracellular pH of 6.9, the pH gradient (delta pH) across the cell membrane was only 0.07 U . As extracellular pH declined from 6.9 to 5.7, intracellular pH decreased to a smaller extent than extracellular pH and delta pH increased . Below pH 5.7, there was a linear and nearly proportional decrease in intracellular pH . B . succinogenes took up the lipophilic cation tetraphenylphosphonium ion (TPP+) in the presence of cellobiose, and uptake was sensitive to the ionophore valinomycin . As pH was decreased with phosphoric acid, the cells lost TPP+ and electrical potential, delta psi, decreased . From extracellular pH 6.9 to 5.7, the decrease in delta psi was compensated for by an increase in delta pH, and the proton motive force ranged from 152 to 158 mV . At a pH of less than 5.7, there was a large decrease in proton motive force, and this decrease corresponded to the inhibition of cellobiose utilization.

J Bacteriol, 1987 Oct, 169(10), 4589 - 96
Nucleotide sequence analysis of Tn4551: use of ermFS operon fusions to detect promoter activity in Bacteroides fragilis; Smith CJ; The Bacteroides pBI136 clindamycin resistance (Ccr) determinant from the composite transposon Tn4551 was cloned onto the shuttle plasmid pFD160, and the regions necessary for expression in Bacteroides fragilis were determined . These results suggested that transcriptional regulatory signals required for Ccr were located in the Tn4551 direct repeat sequence (DRS) adjacent to the resistance determinant . Analysis of the nucleotide sequence of this region revealed that the Ccr structural gene, 798 base pairs (bp), was located 17 bp from the terminus of the DRS and that this gene (ermFS) differed from ermF (pBF4) by one amino acid . The DRS element was found to be 1,155 bp and appeared to contain the ermFS transcription start signals . The DRS structure was typical of insertion sequence elements isolated from other bacterial species, and its termini were characterized by 25-bp regions of imperfect dyad symmetry . The DRS was dominated by a 978-bp open reading frame, which terminated in the left inverted repeat 27 bp from the ermFS start codon, and weak amino acid sequence homology was observed with the putative transposase of IS3 . Promoter activity of the DRS in B . fragilis was demonstrated by in vitro construction of operon fusions with a promoterless ermFS gene followed by transformation of the recombinant plasmids with selection for resistance to clindamycin . The location of one DRS promoter was identified by using the ermFS fusions and then verified by in vitro mutagenesis of the site with single-stranded linkers . Northern blot (RNA blot) analysis of total RNA from B . fragilis strains containing pBI136 or ermFS recombinant plasmids confirmed the location of this promoter and indicated that it was used in vivo by Tn4551 . A second DRS promoter, which activated ermFS transcription by readthrough of the large DRS open reading frame, was also identified by the Northern blot analysis . The bicistronic ermFS message was not observed in strains containing a complete copy of Tn4551, and the possibility of transcriptional regulation is discussed.

Antimicrob Agents Chemother, 1987 Sep, 31(9), 1379 - 82
Interactions of ciprofloxacin with clindamycin, metronidazole, cefoxitin, cefotaxime, and mezlocillin against gram-positive and gram-negative anaerobic bacteria; Whiting JL et al.; A total of 598 clinical isolates of anaerobic bacteria were tested against ciprofloxacin by the agar dilution technique with 10(5) CFU on Wilkins-Chalgren medium . Selected strains representative of the six major genera of anaerobes relatively resistant to the quinolones were tested for interactions with ciprofloxacin in combination with clindamycin, metronidazole, cefoxitin, cefotaxime, or mezlocillin by using a checkerboard agar dilution technique . Cefotaxime-ciprofloxacin and clindamycin-ciprofloxacin were the most effective combinations, with 16% of all isolates and 44% of the Bacteroides fragilis group isolates responding synergistically to the former combination and 9% of all isolates and 37% of Peptostreptococcus isolates responding synergistically to the latter . Occasional synergy was seen with all other antibiotic combinations except for metronidazole-ciprofloxacin . Likewise, synergism was seen with all groups of anaerobes except for Fusobacterium species . Antagonistic interactions were observed only with a Peptostreptococcus intermedius strain tested against clindamycin-ciprofloxacin . These data suggest that combinations of ciprofloxacin with these agents may be useful for certain resistant anaerobic infections.

J Med Microbiol, 1987 Sep, 24(2), 133 - 7
Identification of Bacteroides species from adult periodontal disease; Duerden BI et al.; Samples from deep (4-7 mm) periodontal pockets were collected from 17 patients with adult-type periodontal disease and one with the juvenile form of the disease . They were streaked immediately on selective and non-selective media and incubated anaerobically for 96 h . There was a heavy growth of Bacteroides spp . from most samples and 10 representative colonies from each sample were sub-cultured for identification . In a total of 149 isolates from patients with adult-type disease, the commonest species were B . oralis (40), B . asaccharolyticus (35), B . intermedius (31), B . fragilis (12) and B . ureolyticus (10); B . gingivalis was not detected . The distribution of species was not distorted by multiple identical isolates from individual patients . There was a heavy growth of a single species, B . ureolyticus, from the patient with juvenile-type disease.

J Thorac Cardiovasc Surg, 1987 Sep, 94(3), 414 - 8
Treatment of spontaneous bacterial empyema thoracis; Mandal AK et al.; The need for decortication to cure primary bacterial (nontuberculous) empyema was evaluated in 112 consecutive patients . Twenty-eight patients (25%) were cured by thoracentesis alone . Intercostal chest tube drainage was required in 43 (39%) and decortication in 41 (36%) . Although hospital stay was shortened by 5 days for those who had decortication, the difference was statistically insignificant . Penicillin failed to eradicate infection in nine of 17 patients, four of whom had Bacteroides organisms . There were no therapeutic failures among 46 patients treated with clindamycin and gentamicin . We conclude that conservative therapy, such as thoracentesis, antibiotics directed against anaerobic bacteria, and intercostal tube drainage (thoracostomy), was adequate to achieve clinical and physiologic resolution in about two thirds of all patients with primary bacterial empyema . The remaining one third required decortication . Rib resection and Eloesser flap procedures seem to be unnecessary in the treatment of primary bacterial empyema.

Diagn Microbiol Infect Dis, 1987 Sep, 8(1), 61 - 5
Effect of beta-lactamase inhibitors on the antimicrobial activity of cefoperazone, cefotaxime, and ceftizoxime against aerobic and anaerobic beta-lactamase producing bacteria; Fuchs PC et al.; Clavulanic acid (2.0 micrograms/ml) lowered the minimal inhibitory concentrations (MICs) of ceftizoxime and cefotaxime against 49 strains of the Bacteroides fragilis group by a mean of 4.0 and 3.4 log2 concentrations, respectively . Sulbactam plus ceftizoxime gave almost identical results . Sulbactam lowered cefoperazone MICs by a mean of 2 log2 concentrations . Against 52 aerobic and facultative isolates producing a variety of beta-lactamase types, the use of beta-lactamase inhibitors (sulbactam) was most effective in reducing the MICs of cefoperazone.

J Med Microbiol, 1987 Sep, 24(2), 125 - 31
Difficulties in the serodiagnosis of infection with the fragilis group of Bacteroides; Elhag KM et al.; Bacteroides antibodies were studied in sera from 74 patients infected with the fragilis group of Bacteroides and 74 healthy control persons, by immunofluorescence of 26 different serotypes of the fragilis group . Antibodies were present at titres of 10-320 in 65 (88%) patients and 50 (68%) controls (p less than 0.01) . Titres of greater than or equal to 80 were demonstrated in sera of 38 (51%) patients and 5 (7%) controls (p less than 0.01) . Specific IgM antibodies were detected in sera of 42 (57%) patients at a geometric mean titre (GMT) of 30, and 8 (11%) controls at a GMT of 11 (p less than 0.01) . High antibody titres as well as specific IgM were found in 32 (43%) patients, while none of the controls showed such a combination (p less than 0.01) . The majority of positive patients' sera (57%) reacted with five or more serotypes, whereas most positive control sera (51%) reacted against only one or two serotypes (p less than 0.01) . A selected combination of serotypes not reacting with the control sera showed positive reactions with 52 (70%) patients' sera . These findings may be useful in devising schemes for the serodiagnosis of infection caused by the fragilis group of Bacteroides . However, there are indications of geographic variation in prevalence of serotypes, which may prevent the development of a single universal scheme.

J Med Microbiol, 1987 Sep, 24(2), 119 - 24
Effect of Bacteroides fragilis cellular components on chemotactic activity of polymorphonuclear leukocytes towards Escherichia coli; Namavar F et al.; Chemotaxis of polymorphonuclear leukocytes (PMNL) in response to cell components of Bacteroides fragilis alone or in combination with Escherichia coli was evaluated . E . coli produced much more powerful chemotactic factors than B . fragilis . The culture filtrate (CF), outer membrane (OM) preparation, and lipopolysaccharide (LPS) of B . fragilis slightly stimulated chemotactic activity of PMNL . The culture filtrate and OM preparation were capable of inhibiting the chemotaxis of PMNL in response to the chemotactic factors of E . coli but LPS of B . fragilis was not able to do so . Reduction by B . fragilis of PMNL chemotaxis in response to E . coli was not specific for B . fragilis but also occurred in the presence of facultative bacteria . In parallel with chemotaxis, lysozyme release, but not beta-glucuronidase release, by PMNL was significantly stimulated by E . coli but not by B . fragilis.

Obstet Gynecol, 1987 Sep, 70(3 Pt 1), 384 - 8
Antibiotics and suction drainage as prophylaxis in vaginal and abdominal hysterectomy; Wijma J et al.; A randomized prospective study compared the efficacy of a three-dose perioperative course of intravenously administered cefuroxime and metronidazole versus suction drainage of the vaginal vault for preventing postoperative infection in abdominal and vaginal hysterectomies . In vaginally operated patients, a significant difference in the rate of vaginal cuff abscess formation was found between the drain group and the antibiotic group (33 versus 0%) . In the abdominally operated patients, no significant difference was found (7 versus 0%) . The rate of cystitis was not influenced by the prophylactic method . A positive correlation was found between Bacteroides sp isolated from the vaginal fluid and vaginal cuff abscesses in the vaginally operated women . The complications of infection are explained by the decrease in host defense, occurring more frequently in patients treated with the vaginal approach than with the abdominal technique.

J Bacteriol, 1987 Sep, 169(9), 4018 - 23
Western blot (immunoblot) analysis of the fimbrial antigens of Bacteroides nodosus; Anderson BJ et al.; The roles of the fimbrial subunit and the putative basal protein antigens in the serological classification of Bacteroides nodosus have been examined by Western blot (immunoblot)-antibody binding studies of fimbriae isolated from a wide range of strains representative of different serogroups and serotypes . Fimbrial subunits were recognized by antiserum against the homologous serogroup but not generally by heterologous antisera, whereas recognition of the basal antigen was independent of serological classification . Secondary cross-reaction patterns among fimbrial subunits indicated that some serogroups may be more closely related than others . Examples include serogroups C and G and serogroups D and H . Similar analyses of isolates classified within serotypes A1 and A2, with serotype-specific antisera, showed that this subdivision is also determined by the fimbrial subunit and that significant variation does occur even at this level . These studies suggest that the various serogroups and serotypes of B . nodosus comprise a series of overlapping sets of antigenically related strains.

J Clin Periodontol, 1987 Aug, 14(7), 412 - 7
Effect of periodontal therapy on specific antibody responses to suspected periodontopathogens; Vincent JW et al.; The effects of clinically successful periodontal therapy were studied in juvenile periodontitis (JP) and rapidly progressive periodontitis (RP) patients and compared with periodontally healthy subjects (HS) . Serum samples were obtained in 35 HS prior to the study and in 12 of these subjects 3-4 years later . Serum samples were obtained from 50 JP patients initially, 9 subjects immediately following surgical therapy and 29 of these subjects 3-4 years later . RP patients provided 46 initial serum samples, 9 following therapy and 27 samples 3-4 years later . Antibody levels were determined utilizing a standardized enzyme-linked immunosorbent assay with Bacteroides gingivalis, B . ochracea, Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans serving as antigens . The JP patients showed an initial rise in antibody levels immediately following therapy followed by a significant decrease in antibody levels 3 to 4 years later . The RP patients did not show an early change in antibody levels but by 3 to 4 years post-therapy, antibody levels had significantly decreased . However, during this study, the antibody levels of JP and RP patients remained significantly higher when compared with HS patients.

Br J Oral Maxillofac Surg, 1987 Aug, 25(4), 328 - 33
An unusual case of necrotising fasciitis; Steel A; A case of subcutaneous necrotising ulceration presenting on the chest wall following a dental abscess is described . The course, surgical treatment, chemotherapy and successful outcome of the case are annotated . The bacteriological findings in this and other cases presenting similarly are discussed, and the possible implication of bacteroides species, alone or in conjunction with Str . milleri, as an aetiological factor in this condition is discussed.

J Gen Microbiol, 1987 Aug, 133 ( Pt 8), 2217 - 24
Hexagonal periodicity in the outer membrane of Bacteroides buccae; Kerosuo E et al.; In Bacteroides buccae, a hexagonally arranged periodic structure was found in the outer membrane (OM), in addition to hexagonal lattices present in its external surface layer (S-layer) . This crystalline OM protein (COMP) was present as patches on the concave fracture face (the outer leaflet) of the OM in freeze-fractured cells . Occasionally, hexagonally arranged structures could also be seen on the convex fracture face of the OM as 'fingerprints' of the COMP . The OM proteins were isolated and analysed by gel electrophoresis . The major band protein had an apparent molecular mass of 17 kDa . Whether the minor band proteins are also components in the structure of the COMP remains to be elucidated . Other oral Gram-negative anaerobic rods studied did not show any periodicity in their OM.

J Anim Sci, 1987 Aug, 65(2), 488 - 96
Activity of fiber-degrading microorganisms in the pig large intestine; Varel VH; The large intestine is comparable to the rumen fermentation in many aspects; however, it is understood less well . Fiber in the form of cellulose and hemicellulose is one of the major substrates fermented in the large intestine . Various studies suggest that the pig can utilize fiber for growth, and up to 30% of its maintenance energy may be derived from volatile fatty acids produced in the large intestine . The total number of microorganisms in the pig large intestine do not change when a high fiber diet such as 50 or 80% alfalfa meal is fed . However, the fiber-degrading organisms increase and obviously replace others . The increase in fibrolytic bacteria normally coincides with an increase in enzyme activity (cellulase and xylanase), indicating that diet can be used to enhance fibrolytic activity . This is true for growing pigs and adult animals . The cellulolytic organisms in the pig, Bacteroides succinogenes and Ruminococcus flavefaciens, are similar to those in the rumen and are present at comparable numbers . This partly explains why adult pigs can maintain themselves by merely grazing on forage in pastures . Assuming other conditions are met, there is a significant potential for fiber degradation in the pig large intestine . Whether various genotypes such as the genetically selected obese and lean pigs have different abilities to degrade fiber is unknown . More work is required to understand the interaction of the fibrolytic organisms with the other organisms present in the large intestine, similar to that which has been done in the rumen, as well as the microbe-host interaction.

J Bacteriol, 1987 Aug, 169(8), 3573 - 80
Complete nucleotide sequence of insertion element IS4351 from Bacteroides fragilis; Rasmussen JL et al.; The nucleotide sequence and genetic analyses of one of the directly repeated sequences flanking the macrolide-lincosamide-streptogramin B drug resistance determinant, ermF, from the Bacteroides fragilis R plasmid, pBF4, suggested that this region is an insertion sequence (IS) element . This 1,155-base-pair element contained partially matched (20 of 25 base pairs) terminal-inverted repeats, overlapping, anti-parallel open reading frames, and nine promoterlike sequences, including three that were oriented outward . Analysis of this sequence revealed no significant nucleotide homology to 13 other known IS elements . Inasmuch as Southern blot hybridization analysis detected homologous sequences in chromosomal DNA and its G+C content (42 mol%) was similar to that of B . fragilis, the data suggested that this element is of Bacteroides origin . Transposition promoted by this element was demonstrated in recA E . coli . Recombinants were recovered by selecting for the activation of a promoterless chloramphenicol resistance gene on the plasmid pDH5110 and were characterized by restriction endonuclease mapping and Southern blot hybridization . We propose that this IS element be designated IS4351.

J Bacteriol, 1987 Aug, 169(8), 3450 - 7
Transposition of Tn4551 in Bacteroides fragilis: identification and properties of a new transposon from Bacteroides spp; Smith CJ et al.; Tn4551, a clindamycin resistance (Ccr) transposon from the R plasmid pBI136, was cloned onto an Escherichia coli-Bacteroides shuttle vector which could replicate normally in E . coli but was maintained unstably in Bacteroides fragilis . To aid in cloning and to ensure maintenance of Tn4551 in E . coli, a kanamycin resistance determinant (Kmr) was inserted in the transposon . The transposon-bearing shuttle vector pFD197 was transformed into B . fragilis 638, and putative insertions of Tn4551::Kmr were identified by screening for resistance to clindamycin and plasmid content . Southern hybridization analyses were used to verify integration of the transposon in the B . fragilis chromosome, and the frequency of insertion was estimated at 7.8 X 10(-5) events per generation . In 57% of the isolates tested a second integration event also occurred . This second insertion apparently involved just a single copy of the 1.2-kilobase repeat sequence which flanks the transposon . In addition, Tn4551::Kmr appeared to function as a transposon in E . coli . Evidence for this was obtained by the isolation of transposon insertions into the bacteriophage P1 genome . Finally, the transposon vector, pFD197, could be mobilized to other B . fragilis strains in which transposition was detected . Mobilization from the strain 638 background was via a conjugation like process, but occurred in the absence of known conjugative elements or other detectable plasmids . This result suggested the presence of a host-encoded transfer system in this B . fragilis strain.

Microb Pathog, 1987 Aug, 3(2), 87 - 95
Characterization of fimbriae from Bacteroides fragilis; van Doorn J et al.; Fimbriae derived from Bacteroides fragilis strain BE1 (BE1 fimbriae) appeared to be composed of subunits with a molecular weight of 40,000 . Under the electron microscope the fimbriae could be visualized as straight filaments with a diameter of 4 nm . It appeared that production of the BE1 fimbriae is repressed under conditions of iron limitation, and at a growth temperature of 20 degrees C . Antibodies raised against the 40,000 dalton polypeptide, purified by means of preparative SDS-polyacrylamide gelelectrophoresis, recognized the native fimbriae, as was shown by immunogold labelling of intact bacterial cells, and by immunoprecipitation . Immunoblot experiments showed that other strains of B fragilis tested produced polypeptides, ranging in molecular weight from 40,000 to 42,000, that are antigenically related to the BE1 fimbrial subunit . No haemagglutination activity could be associated with the BE1 fimbriae.

Scand J Dent Res, 1987 Aug, 95(4), 308 - 14
Fibronectin fragmentation induced by dental plaque and Bacteroides gingivalis; Larjava H et al.; Degradation of fibronectin (FN) by subgingival and supragingival plaque and Bacteroides gingivalis (Bg) was studied in vitro . The degradation of FN by both types of plaque was relatively rapid, continuous but incomplete . Some differences were found between supra- and subgingival samples . Supragingival plaque extracts produced several FN fragments of 110-180 kd during short incubations of 15-60 min . The predominant fragment after overnight incubation was a 110 kd polypeptide . With subgingival plaque extract a more extensive degradation of FN was noted . The main degradation product was a 120 kd fragment after overnight incubation . Several peptide fragments were released from fibronectin by Bg extracts . Their molecular size was different from those produced by trypsin, elastase or dental plaque . When cell extracts of Bg were fractionated by high performance liquid chromatography, three separate peaks of fibronectin degrading activity were obtained . Two of those peaks also contained trypsin-like enzyme activity . The degradation of fibronectin and the subsequent formation of biologically active peptides may have many effects in periodontal pockets . These may include modifying effects on plaque growth and wound healing.

Diagn Microbiol Infect Dis, 1987 Aug, 7(4), 273 - 8
Preparation of ribonucleic acid probes specific for Bacteroides fragilis; Groves DJ et al.; Nucleic acid probes promise to be very useful in the detection of infectious agents . Several RNA probes have been developed by random cloning of chromosomal DNA for the detection of Bacteroides fragilis . Four such probes prepared by transcription of inserts of 400 bp, 800 bp, 2.4 kbp, and 6 kbp all hybridized to denatured B . fragilis DNA on nitrocellulose, but did not bind to DNA from a variety of other Bacteroides spp . or from selected aerobic strains . Each probe readily detected five clinical isolates of B . fragilis and did not react with 11 clinical isolates representing four other species in the "B . fragilis group".

Vet Rec, 1987 Jul 18, 121(3), 60 - 2
Vaccination against lumpy jaw and measurement of antibody response in wallabies (Macropus eugenii); Blanden DR et al.; Successful protection against lumpy jaw disease in a colony of captive wallabies (Macropus eugenii) was induced by vaccination with a commercial ovine footrot vaccine . No mortalities attributable to lumpy jaw were observed in 69 vaccinated animals while six of 42 unvaccinated control wallabies died of the disease . Vaccinated animals exhibited significant increases in antibody titres to Bacteroides nodosus after the first and second doses of vaccine . Titres were measured by an enzyme-linked immunosorbent assay.

J Gen Microbiol, 1987 Jul, 133 ( Pt 7), 1975 - 81
Glucose-6-phosphate dehydrogenase and malate dehydrogenase enzyme electrophoretic patterns amongst strains of Bacteroides fragilis; Shah HN et al.; Fifty-two strains of Bacteroides fragilis were examined for their enzyme electrophoretic patterns of glucose-6-phosphate dehydrogenase (G6PDH) and malate dehydrogenase (MDH) . All strains tested possessed high levels of both enzymes but the G6PDH reduced NADP whereas MDH was NAD-dependent . Twenty-seven strains produced single bands of both G6PDH and MDH . In all cases G6PDH migrated faster than MDH . Strains clustered by a single linkage algorithm were recovered in eight clusters at the 77% similarity level . The remaining 25 strains produced multiple bands of one or both enzymes . These were recovered in six clusters at the 72% similarity level using the same algorithm . The results of this study revealed considerable heterogeneity of enzyme patterns within B . fragilis.

Infect Immun, 1987 Jul, 55(7), 1725 - 7
Polymorphonuclear neutrophil chemotaxis modulated by Bacteroides fragilis peptidoglycan; Sperry JF et al.; Peptidoglycan was isolated from Bacteroides fragilis with boiling sodium dodecyl sulfate, and some was treated with pronase to eliminate contaminating protein . This peptidoglycan was chemotactic for rabbit polymorphonuclear neutrophils and had even greater chemotactic activity along with some chemokinetic activity after it was partially hydrolyzed with lysozyme . Significant chemotaxis-inhibitory activity was observed for an acid-precipitable component of the lysozyme-treated crude peptidoglycan of B . fragilis.

J Clin Periodontol, 1987 Jul, 14(6), 326 - 33
Clinical and microbiological effects of fixed orthodontic appliances; Diamanti-Kipioti A et al.; The purpose of this clinical and microbiological study was to evaluate longitudinally the changes occurring in the subgingival microbiota in children following the placement of orthodontic bands in the absence of a prophylactic oral hygiene program . A total of 12 children in the age between 10 and 15 years were selected for the study . The experimental group (E) consisted of 6 subjects scheduled for orthodontic treatment including the placement of fixed appliances . They were seen 1 week before and just prior to the placement of orthodontic bands . The control group (C) involved 6 children in the maintenance phase of orthodontic therapy in which removable retainers were used . All subjects were examined at 3-5 week intervals for a period of 4 months . At each examination, microbiological subgingival plaque samples were collected by means of sterile paper points . Plaque and gingival index scores as well as pocket probing depth at the site of sampling were determined . The microbiological samples were processed using continuous anaerobic culturing techniques and were plated on non-selective and selective media . Differential counts and biochemical characterization of isolates were performed according to the methods described by Kornman and Loesche . Following tooth-banding, an increase in pocket probing depth was observed, while the P1I and GI scores remained unaffected . A statistically significant increase from baseline values (p less than 0.05) was found for the %s of black-pigmented bacteroides, the B . intermedius and A . odontolyticus species, concomitantly with a decrease of the anaerobe/facultative bacteria ratio in the experimental, but not the control sites.(ABSTRACT TRUNCATED AT 250 WORDS)

J Clin Periodontol, 1987 Jul, 14(6), 307 - 14
A clinical, demographic and microbiologic study of ANUG patients in an urban dental school; Falkler WA Jr et al.; 35 ANUG patients were examined and compared clinically and demographically . Plaque removed from ulcerated sites in 20 patients was cultured using quantitative anaerobic procedures and examined by electron and darkfield microscopy . Patients were classified as having ANUG when presenting with ulceration and necrosis of interproximal papillae, pain and bleeding . The clinical symptoms of fetid odor, pseudomembrane formation, lymphadenopathy and elevated body temperature were present in 97%, 85%, 61% and 39% of the ANUG patients, respectively . 83% of the patients were smokers . The ANUG patients demonstrated a lower average age (24 years) than the general clinic population (32 years) . There was a slightly higher % of male (54%) than female (46%) and the % of Caucasian (51%) and black (49%) ANUG patients were almost equal . Cultural studies revealed that gram-negative rods were the predominant cultivable micro-organisms present in the plaque, representing 78.2% of the total recoverable count . Of these, nearly half were strict anaerobes with Bacteroides gingivalis and Fusobacterium nucleatum accounting for 7.8% and 3.4%, respectively . Anaerobic and facultative gram-positive cocci (15.5%), gram-negative cocci (3.5%) and gram-positive rods (2.8%) were also isolated . Microscopic analysis of the morphologic composition of plaque revealed that rods (43%) constituted the greatest % of the total microorganisms observed followed by spirochetes (30%) and cocci (27%) . 8 distinct types of spirochetal periplasmic flagellar arrangement were observed by electron microscopy, the "2-4-2" periplasmic flagellar arrangement being most numerous.

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