Curr Opin Microbiol, 1998 Apr, 1(2), 170 - 4 Initiation of bacterial development; Hoch JA; The discovery of a mitotic apparatus in bacteria has led to significant recent progress being made in understanding the regulatory connections between the cell cycle, chromosome segregation and the onset of developmental processes in sporulation . The control of developmental transcription by antagonism between protein kinase and protein phosphatase reached a new level of complexity with the discovery of peptide inhibitors of protein phosphatases that cycle between the interior and exterior cell surface as information messengers . New mechanisms of developmental regulation are being uncovered in a variety of microbial systems. Curr Opin Microbiol, 1998 Feb, 1(1), 12 - 6 Microbial genome sequencing and pathogenesis; Tang CM et al.; The year 1997 saw the publication of the complete nucleotide sequence of Helicobacter pylori and Escherichia coli . It is conceivable that the complete nucleotide sequence for all the major human bacterial pathogens will be available by the end of the century . Database alignments have been used to ascribe the putative functions of open reading frames in the sequenced isolates and to define the differences between bacterial species at the nucleotide level . The most striking finding from all genome projects has been the high proportion of open reading frames that have no known function . Experimental data demonstrating the utility of the genome sequencing projects are only just beginning to emerge. J Anim Sci, 1999 Jan, 77(1), 187 - 93 Mechanical maceration of alfalfa; Hintz RW et al.; Maceration is an intensive forage-conditioning process that can increase field drying rates by as much as 300% . Because maceration shreds the forage and reduces its rigidity, improvements in bulk density, silage compaction, and ensiling characteristics have been observed . Macerating forage also increases the surface area available for microbial attachment in the rumen, thereby increasing forage digestibility and animal performance . Feeding trials with sheep have shown increases in DMI of 5 to 31% and increases in DM digestibility of from 14 to 16 percentage units . Lactation studies have demonstrated increases in milk production and BW gain for lactating Holstein cows; however, there is a consistent decrease in milk fat percentage when dairy cattle are fed macerated forage . In vitro studies have shown that maceration decreases lag time associated with NDF digestion and increases rate of NDF digestion . In situ digestibility studies have shown that maceration increases the size of the instantly soluble DM pool and decreases lag time associated with NDF digestion, but it may not consistently alter the rate or extent of DM and NDF digestion. Sci Total Environ, 1999 Jan 26, 225(3), 181 - 209 Natural and anthropogenic inputs of hydrocarbons to the Strait of Georgia; Yunker MB et al.; Sediment cores from the Fraser estuary, Vancouver Harbour and Strait of Georgia, suspended sediment samples from the Fraser River and sediment grabs from Vancouver Harbour have been analyzed for alkanes and parent and alkyl PAHs (polycyclic aromatic hydrocarbons) . Principal components analysis (PCA) clearly distinguishes mixed sources by separating parent PAHs according to molecular size, and separating alkyl substituted PAHs from higher plant PAHs . We find the Fraser River to be the predominant source for natural and anthropogenic hydrocarbons to the Strait of Georgia . The natural hydrocarbon burden from the Fraser River is augmented principally by petroleum hydrocarbons and combustion PAHs from Vancouver . Contaminated sediments from Vancouver Harbour very likely have also been transported to a major ocean disposal site off the Fraser estuary . Petroleum alkanes, which dominate Fraser River suspended sediment samples, are lost by processes such as dissolution or microbial degradation during transport and sedimentation, while PAHs from the river are delivered essentially unchanged to sediments in the strait . Hydrocarbon composition undergoes little change with depth at a reference location in the Strait of Georgia, indicating that PAH inputs have changed very little since the early part of this century . In Vancouver Harbour the low rate of sediment accumulation coupled with surface mixing has led to the retention of contaminant PAHs within the surface mixed layer, while the rapid delivery of sediments from the Fraser River has buried contaminant PAHs from historical ocean disposal in the Strait of Georgia. Proc Natl Acad Sci U S A, 1999 Mar 2, 96(5), 2373 - 8 Induction of autoantibodies to mouse CCR5 with recombinant papillomavirus particles; Chackerian B et al.; The vertebrate immune system has evolved to respond vigorously to microbial infection but to ignore self-antigens . Evidence has emerged that B cell responses to viruses are initiated by immune recognition of ordered arrays of antigen on the viral surface . To test whether autoantibodies against a self-antigen can be induced by placing it in a context that mimics the ordered surface of a viral particle, a peptide representing an extracellular loop of the mouse chemokine receptor CCR5 was incorporated into an immunodominant site of the bovine papillomavirus virus L1 coat protein, which self-assembles into virus-like particles . Mice inoculated with chimeric L1-CCR5 particles generated autoantibodies that bound to native mouse CCR5, inhibited binding of its ligand RANTES, and blocked HIV-1 infection of an indicator cell line expressing a human-mouse CCR5 chimera . These results suggest a general method for inducing autoantibodies against self-antigens, with diverse potential basic research and clinical applications. Proc Natl Acad Sci U S A, 1999 Mar 2, 96(5), 2204 - 9 Yeast and human genes that affect the Escherichia coli SOS response; Perkins EL et al.; The sequencing of the human genome has led to the identification of many genes whose functions remain to be determined . Because of conservation of genetic function, microbial systems have often been used for identification and characterization of human genes . We have investigated the use of the Escherichia coli SOS induction assay as a screen for yeast and human genes that might play a role in DNA metabolism and/or in genome stability . The SOS system has previously been used to analyze bacterial and viral genes that directly modify DNA . An initial screen of meiotically expressed yeast genes revealed several genes associated with chromosome metabolism (e.g., RAD51 and HHT1 as well as others) . The SOS induction assay was then extended to the isolation of human genes . Several known human genes involved in DNA metabolism, such as the Ku70 end-binding protein and DNA ligase IV, were identified, as well as a large number of previously unknown genes . Thus, the SOS assay can be used to identify and characterize human genes, many of which may participate in chromosome metabolism. Appl Environ Microbiol, 1999 Mar, 65(3), 1251 - 8 Identification of a novel group of bacteria in sludge from a deteriorated biological phosphorus removal reactor; Nielsen AT et al.; The microbial diversity of a deteriorated biological phosphorus removal reactor was investigated by methods not requiring direct cultivation . The reactor was fed with media containing acetate and high levels of phosphate (P/C weight ratio, 8:100) but failed to completely remove phosphate in the effluent and showed very limited biological phosphorus removal activity . Denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA was used to investigate the bacterial diversity . Up to 11 DGGE bands representing at least 11 different sequence types were observed; DNA from the 6 most dominant of these bands was further isolated and sequenced . Comparative phylogenetic analysis of the partial 16S rRNA sequences suggested that one sequence type was affiliated with the alpha subclass of the Proteobacteria, one was associated with the Legionella group of the gamma subclass of the Proteobacteria, and the remaining four formed a novel group of the gamma subclass of the Proteobacteria with no close relationship to any previously described species . The novel group represented approximately 75% of the PCR-amplified DNA, based on the DGGE band intensities . Two oligonucleotide rRNA probes for this novel group were designed and used in a whole-cell hybridization analysis to investigate the abundance of this novel group in situ . The bacteria were coccoid and 3 to 4 microm in diameter and represented approximately 35% of the total population, suggesting a relatively close agreement with the results obtained by the PCR-based DGGE method . Further, based on electron microscopy and standard staining microscopic analysis, this novel group was able to accumulate granule inclusions, possibly consisting of polyhydroxyalkanoate, inside the cells. Adv Parasitol, 1999, 42, 343 - 410 DNA vaccines: technology and application as anti-parasite and anti-microbial agents; Alarcon JB et al.; DNA vaccines have been termed The Third Generation of Vaccines . The recent successful immunization of experimental animals against a range of infectious agents and several tumour models of disease with plasmid DNA testifies to the powerful nature of this revolutionary approach in vaccinology . Among numerous advantages, a major attraction of DNA vaccines over conventional vaccines is that they are able to induce protective cytotoxic T-cell responses as well as helper T-cell and humoral immunity . Here we review the current state of nucleic acid vaccines and cover a wide range of topics including delivery mechanisms, uptake and expression of plasmid DNA, and the types of immune responses generated . Further, we discuss safety issues, and document the use of nucleic acid vaccines against viral, bacterial and parasitic diseases, and cancer . The early potential promise of DNA vaccination has been fully substantiated with recent, exciting developments including the movement from testing DNA vaccines in laboratory models to non-human primates and initial human clinical trials . These advances and the emerging voluminous literature on DNA vaccines highlight the rapid progress that has been made in the DNA immunization field . It will be of considerable interest to see whether the progress and optimism currently prevailing can be maintained, and whether the approach can indeed fulfil the medical and commerical promise anticipated. PDA J Pharm Sci Technol, 1998 Nov-Dec, 52(6), 326 - 30 Statistical analysis of environmental monitoring data: does a worst case time for monitoring clean rooms exist? Cundell AM, Bean R, Massimore L, Maier C. To determine the relationship between the sampling time of the environmental monitoring, i.e., viable counts, in aseptic filling areas and the microbial count and frequency of alerts for air, surface and personnel microbial monitoring, statistical analyses were conducted on 1) the frequency of alerts versus the time of day for routine environmental sampling conducted in calendar year 1994, and 2) environmental monitoring data collected at 30-minute intervals during routine aseptic filling operations over two separate days in four different clean rooms with multiple shifts and equipment set-ups at a parenteral manufacturing facility . Statistical analyses showed, except for one floor location that had significantly higher number of counts but no alert or action level samplings in the first two hours of operation, there was no relationship between the number of counts and the time of sampling . Further studies over a 30-day period at the floor location showed no relationship between time of sampling and microbial counts . The conclusion reached in the study was that there is no worst case time for environmental monitoring at that facility and that sampling any time during the aseptic filling operation will give a satisfactory measure of the microbial cleanliness in the clean room during the set-up and aseptic filling operation. Appl Environ Microbiol, 1999 Mar, 65(3), 982 - 8 Effect of phenylurea herbicides on soil microbial communities estimated by analysis of 16S rRNA gene fingerprints and community-level physiological profiles; el Fantroussi S et al.; The effect of three phenyl urea herbicides (diuron, linuron, and chlorotoluron) on soil microbial communities was studied by using soil samples with a 10-year history of treatment . Denaturing gradient gel electrophoresis (DGGE) was used for the analysis of 16S rRNA genes (16S rDNA) . The degree of similarity between the 16S rDNA profiles of the communities was quantified by numerically analysing the DGGE band patterns . Similarity dendrograms showed that the microbial community structures of the herbicide-treated and nontreated soils were significantly different . Moreover, the bacterial diversity seemed to decrease in soils treated with urea herbicides, and sequence determination of several DGGE fragments showed that the most affected species in the soils treated with diuron and linuron belonged to an uncultivated bacterial group . As well as the 16S rDNA fingerprints, the substrate utilization patterns of the microbial communities were compared . Principal-component analysis performed on BIOLOG data showed that the functional abilities of the soil microbial communities were altered by the application of the herbicides . In addition, enrichment cultures of the different soils in medium with the urea herbicides as the sole carbon and nitrogen source showed that there was no difference between treated and nontreated soil in the rate of transformation of diuron and chlorotoluron but that there was a strong difference in the case of linuron . In the enrichment cultures with linuron-treated soil, linuron disappeared completely after 1 week whereas no significant transformation was observed in cultures inoculated with nontreated soil even after 4 weeks . In conclusion, this study showed that both the structure and metabolic potential of soil microbial communities were clearly affected by a long-term application of urea herbicides. J Clin Periodontol, 1999 Feb, 26(2), 113 - 23 Etiologic models for incident periodontal attachment loss in older adults; Elter JR et al.; Etiologic factors for incident periodontal attachment loss (ALOSS) have not been conclusively identified . The purpose of this study was to develop etiologic models for ALOSS in older adults . Data on 697 older blacks and whites were obtained from 5 sequential examinations over 7 years in the Piedmont 65+ dental study, a complex random sample of older adults in North Carolina . Multivariable Poisson regression models were fit for average number of ALOSS events per person or site month at risk . In models for whites, molar sites, sites with adjacent caries, sites in persons who had: Porphyromonas gingivalis (P.g.) at least 2% of total microbial count (TMC), never had a dental checkup, more depression symptoms, fewer than 12 years of education, higher BANA score, or smoked, had significantly higher rates of ALOSS . In a separate model for blacks, interproximal and molar sites, sites in blacks who had: P.g . at least 2% of TMC, higher BANA score, never had a dental checkup, lower socioeconomic status (SES), or smoked, had significantly higher rates of ALOSS . These results confirm a multifactorial etiology for ALOSS in older adults and indicate that interventions aimed at infection, smoking, and preventive dental care utilization, may be most useful. Arch Bronconeumol, 1999 Jan, 35(1), 27 - 32 {Community-acquired pneumonia referred for hospital management . Its epidemiology and the diagnostic and therapeutic approaches}; Carretero Gracia JA et al.; OBJECTIVES: To determine the epidemiology of community-acquired pneumonia referred to the hospital and to characterize the diagnostic and therapeutic approach adopted by physicians . METHOD: Retrospective epidemiological and descriptive clinical study based on case histories consistent with a diagnosis of community-acquired pneumonia (Fang et al . Medicine, 1990; 69:307-16) of patients referred to hospitals in Soria (Spain) over a period of one year . The patients were grouped by severity and the presence of risk factors for unusual etiology . Initial approaches were compared to those advocated by various sources . RESULTS: Three hundred eight cases of community-acquired pneumonia were diagnosed, and 82% of the patients were admitted . Mean age was 68 +/- 26 years (43% over 80 years of age) . Men accounted for 56% . Two hundred seventeen patients (70%) were classified as seriously ill, 203 (66%) had risk factors for unusual etiology, and 166 (54%) were classified in both categories . Mortality among admitted patients was 13% . Etiological diagnoses did not correspond to the guidelines of the Spanish Society of Pneumology and Chest Surgery (SEPAR), with microbial identification achieved in 5% . Empirical treatment followed SEPAR guidelines in 45% of the cases . The Mensa guidelines were followed in 23% and the Sanford guidelines in 20% . CONCLUSIONS: The incidence of community-acquired pneumonia in this population is 3.2 cases per 1,000 inhabitants/year . The population is mainly elderly and comorbidity is common, although mortality is low . We believe common criteria should be adopted for managing community-acquired pneumonia and that empirical treatment should be directed toward germs identified in each setting, based on appropriate etiological investigation. Curr Opin Immunol, 1999 Feb, 11(1), 13 - 8 The Toll-receptor family and control of innate immunity; Kopp EB et al.; Innate immune recognition is mediated by a system of germline-encoded receptors that recognize conserved molecular patterns that are associated with microbial pathogens . These receptors are coupled to signal transduction pathways that control expression of a variety of inducible immune-response genes . Toll receptors and the associated signaling pathways of nuclear factor kappaB may represent the most ancient host defense system found in mammals, insects and plants. Nippon Rinsho, 1999 Jan, 57(1), 43 - 52 {Characteristics of anti-microbial agents and its clinical choice for H . pylori treatment}; Aoyama N et al.; Eradication of Helicobacter pylori (H . pylori) is now established as main treatment of upper-gastrointestinal diseases . Resistance to H . pylori and acid condition in the stomach were important factors which influenced H . pylori eradication . Recolonized H . pylori strains will be easily resistant to metronidazole and clarithromycin, whereas almost all of H . pylori strains are sensitive to amoxicillin . On the other hand, amoxicillin targets cell wall biosynthesis and clarithromycin inhibits protein synthesis of Helicobacter pylori mainly in the growth phase which induced high intragastric pH condition, however, metronidazole targets DNA and, therefore, is independent of the stationary or growth phase distribution . To established a optimal regimen for Helicobacter pylori treatment, several factors included them should be account according to the parmacokinetical standings. Int Rev Immunol, 1998, 17(5-6), 339 - 63 T cell receptor repertoire in rheumatoid arthritis; Goronzy JJ et al.; CD4+ T cells are a major component of the inflammatory infiltrate in rheumatoid synovitis . Within synovial lesions, clonal CD4+ T cell populations are detectable, supporting the notion of an antigen specific recognition even in the joint . In general, the clonal size of individual T cell clones is small and does not lead to a marked distortion of the synovial T cell receptor (TCR) repertoire . Comparison of TCR sequences derived from different patients has not provided evidence for common sequences . Either multiple antigens are recognized or the TCR repertoire is sufficiently plastic with a multitude of different TCR structures responding to the same antigen(s) . However, within one individual, the repertoire of clonal T cell populations is restricted . Identical T cell clones can be identified in different joints and at different timepoints of the disease, emphasizing that the spectrum of antigens recognized is conserved over time and that the T cell response pattern is not subject to evolution . Characterization of antigens involved in the latter stages of the disease may thus provide critical information on disease-initiating events . Recent data have led to the new concept that the role of T cells in rheumatoid arthritis (RA) is not limited to synovial inflammation . Evidence has been provided that the premorbid TCR repertoires of RA patients and normal controls can be distinguished . The T cell repertoire in RA patients is prone to recognize certain microbial products and autoantigens . The selection of this response pattern can only partially be attributed to the disease associated HLA-DRB1 alleles . Additional factors common in RA patients but not in HLA-DR matched control individuals seem to be important in shaping the TCR repertoire . Furthermore, the repertoire of mature T cells in RA patients is characterized by oligoclonality which involves T cells in the peripheral blood compartment . Possibly, these clonal T cell populations react to widespread autoantigens, raising the possibility that RA patients have a defect in controlling peripheral tolerance and an anomaly of lymphoproliferation . In contrast to joint residing CD4+ T cells, expanded clonotypes isolated from the blood of different patients have been described to share TCR beta chain structures . How these characteristic features of the global TCR repertoire in RA patients translate into mechanisms of disease remains to be elucidated. Biol Res, 1998, 31(4), 329 - 38 Is there a mucosal immune system associated with the mammalian oviduct? Cardenas H, Corvalan L, Imarai M. The oviduct is a key component of the reproductive system where essential states such as spermatozoa capacitation, fertilization and early embryo development take place . Recently, an additional role for the entire female reproductive tract has emerged with important implications for our understanding and management of reproductive health, namely, its role in mounting local immune responses against microbial pathogens . Most of the evidence about mucosal immune responses in the female reproductive tract is related to the vagina, with less information available for the uterus . The less known segment in this regard is the oviduct, which prompted us to review and summarize the current state of knowledge on the immune system at the level of the mammalian oviduct . A comprehensive search was conducted in Medline and--for the last two years--also in Current Contents . Result demonstrate that the mammalian oviduct is endowed with many of the elements that characterize a mucosal immune system . However, there are gaps in our knowledge that, in addition to important interspecies differences, make it essential to explore further some fundamental questions regarding this system. J Gastroenterol Hepatol, 1999 Jan, 14(1), 32 - 8 Optimal treatment for duodenal ulcer disease: a cost-decision analysis in Malaysian patients; Goh KL et al.; The aim of the present study was to determine the cost-efficiency of different duodenal ulcer disease treatment practices in Malaysia . Six Malaysian gastroenterologists met to discuss the direct costs related to Helicobacter pylori (HP) eradication treatment . Five treatment strategies were compared: (i) histamine H2 receptor antagonists (H2RA), acid suppression therapy for 6 weeks followed by maintenance therapy as needed; (ii) bismuth triple + proton pump inhibitor (PPI), bismuth (120 mg, q.i.d.), metronidazole (400 mg; t.i.d.), tetracycline (500 mg, q.i.d.) for 7 days and PPI, b.i.d., for 7 days; (iii) OAC, omeprazole (20 mg, b.i.d.), amoxycillin (1000 mg, b.i.d.) and clarithromycin (500 mg, b.i.d.) for 7 days; (iv) OMC, omeprazole (20mg, b.i.d.), metronidazole (400mg, b.i.d.) and clarithromycin (500 mg, b.i.d.) for 7 days; and (v) OAM, omeprazole (20 mg, b.i.d.), amoxycillin (1000 mg, b.i.d.) and metronidazole (400 mg, b.i.d.) for 7 days . A decision tree model was created to determine which therapy would be the most cost-effective . The model considered eradication rates, resistance to anti-microbial agents, compliance and cost implications of treatment regimens, physician visits and ulcer recurrences during a 1 year time period assumption . The H2RA maintenance therapy was the most expensive treatment at Malaysian Ringgit (MR) 2335, followed by bismuth triple therapy (MR 1839), OMC (MR 1786), OAM (MR 1775) and OAC, being the most cost-effective therapy, at MR 1679 . In conclusion, HP eradication therapy is superior to H2RA maintenance therapy in the treatment of duodenal ulcer disease . Of the HP eradication regimens, OAC is the most cost-effective. Int J Syst Bacteriol, 1999 Jan, 49 Pt 1, 149 - 62 New genus-specific primers for the PCR identification of members of the genera Pseudonocardia and Saccharopolyspora; Moron R et al.; Members of the family Pseudonocardiaceae are difficult to identify on the basis of their micromorphology only . The biochemical characterization of each new isolate is a painstaking and time-consuming task which cannot always be undertaken when handling large numbers of strains as is the case in natural product screening programmes . In this study, two sets of genus-specific oligonucleotides were designed which allow rapid detection of members of the genera Pseudonocardia and Saccharopolyspora by means of PCR-specific amplification . The genus specificity of these primers was validated on a wide range of collection strains and the primers were subsequently used to study a group of 106 wild-type isolates that possessed morphological characteristics of the family . Out of this group, 51 strains could be identified as members of the genus Pseudonocardia and only nine isolates could be assigned to the genus Saccharopolyspora . The diversity indicated by whole-cell fatty acid profiles of both wild-type and reference strains was compared with that identified using the oligonucleotide primers . The partial 16S rDNA sequencing of representative wild-type strains was used to validate their genus assignment by PCR-specific amplification . This study shows the industrial usefulness of the application of these direct identification tools as well as the complementary use of two sources of data, PCR-specific amplification results and fatty acid composition, to assess the diversity of a microbial population. FEBS Lett, 1999 Jan 29, 443(3), 290 - 6 Kinetics of oxidation of aliphatic and aromatic thiols by myeloperoxidase compounds I and II; Burner U et al.; Myeloperoxidase (MPO) is the most abundant protein in neutrophils and plays a central role in microbial killing and inflammatory tissue damage . Because most of the non-steroidal anti-inflammatory drugs and other drugs contain a thiol group, it is necessary to understand how these substrates are oxidized by MPO . We have performed transient kinetic measurements to study the oxidation of 14 aliphatic and aromatic mono- and dithiols by the MPO intermediates, Compound I (k3) and Compound II (k4), using sequential mixing stopped-flow techniques . The one-electron reduction of Compound I by aromatic thiols (e.g . methimidazole, 2-mercaptopurine and 6-mercaptopurine) varied by less than a factor of seven (between 1.39 +/- 0.12 x 10(5) M(-1) s(-1) and 9.16 +/- 1.63 x 10(5) M(-1) s(-1)), whereas reduction by aliphatic thiols was demonstrated to depend on their overall net charge and hydrophobic character and not on the percentage of thiol deprotonation or redox potential . Cysteamine, cysteine methyl ester, cysteine ethyl ester and alpha-lipoic acid showed k3 values comparable to aromatic thiols, whereas a free carboxy group (e.g . cysteine, N-acetylcysteine, glutathione) diminished k3 dramatically . The one-electron reduction of Compound II was far more constrained by the nature of the substrate . Reduction by methimidazole, 2-mercaptopurine and 6-mercaptopurine showed second-order rate constants (k4) of 1.33 +/- 0.08 x 10(5) M(-1) s(-1), 5.25 +/- 0.07 x 10(5) M(-1) s(-1) and 3.03 +/- 0.07 x 10(3) M(-1) s(-1) . Even at high concentrations cysteine, penicillamine and glutathione could not reduce Compound II, whereas cysteamine (4.27 +/- 0.05 x 10(3) M(-1) s(-1)), cysteine methyl ester (8.14 +/- 0.08 x 10(3) M(-1) s(-1)), cysteine ethyl ester (3.76 +/- 0.17 x 10(3) M(-1) s(-1)) and alpha-lipoic acid (4.78 +/- 0.07 x 10(4) M(-1) s(-1)) were demonstrated to reduce Compound II and thus could be expected to be oxidized by MPO without co-substrates. Poult Sci, 1999 Jan, 78(1), 75 - 9 Effects of microbial phytase supplementation on egg production, eggshell quality, and mineral retention of laying hens fed different levels of phosphorus; Um JS et al.; A 20-wk feeding trial (21 to 40 wk of age) was conducted to evaluate the effects of phytase supplementation on egg production, egg quality, nutrient retention, and P excretion of laying hens fed diets containing different levels of P . Nine hundred and sixty ISA Brown hens were randomly allocated to completely randomized block arrangement of four diets: corn-soybean diet (1.4% tricalcium phosphate, TCP) without (T1, control) and with phytase (T2); 0.7% TCP (T3) or 0% TCP (T4) diet with phytase . Dietary microbial phytase was added at a level of 500 U/kg . Both hen-day and hen-housed egg production of T2 were significantly (P < 0.05) higher than other treatments, which were not different among themselves . Egg weights were also significantly (P < 0.05) different among treatments ,with T2 being the highest . Feed consumption of T2 was significantly (P < 0.05) higher than other treatments but feed conversion ratio was not significantly different from others . Specific gravity and shell thickness of the eggs were highest in the control (T1) but eggshell strength and broken egg to total egg ratio were not different among treatments . Haugh units were not different among treatments . Retention of Ca, P, Mg, Fe, and Zn were greater (P < 0.05) in phytase-supplemented groups . There were significant (P < 0.05) differences in excretion of ash, P, and Zn . The excretion of these components were highest in the control, whereas P excretion was significantly lower in the T3 and T4 groups . In conclusion, supplementation of the microbial phytase to normal corn-soybean diet improved egg production and can reduce TCP level in the diet without affecting egg production and egg quality . Significant reduction of P excretion can be also achieved. J Endod, 1998 Oct, 24(10), 659 - 62 Intraorifice sealing of gutta-percha obturated root canals to prevent coronal microleakage; Pisano DM et al.; A study was conducted to evaluate Cavit, Intermediate Restorative Material, and Super-EBA as intraorifice filling materials to prevent coronal microleakage . Root canal instrumentation and obturation was done on 74 extracted single-rooted teeth . Three and one-half millimeters of the gutta-percha was removed from the coronal aspect of the root canal and replaced with one of the three filling materials . The teeth were suspended in scintillation vials containing trypticase soy broth, and human saliva was added to the pulp chambers . Microbial penetration was detected as an increase in turbidity of the broth corresponding to bacterial growth . At the end of 90 days, the results showed that 15% of the Cavit-filled orifices leaked, whereas 35% of the Intermediate Restorative Material and Super-EBA-filled orifices leaked . The gutta-percha obturated root canals that received an intraorifice filling material leaked significantly less than the obturated, unsealed control group--all of which leaked in < 49 days. Genome Res, 1999 Feb, 9(2), 175 - 81 Optical mapping of Plasmodium falciparum chromosome 2; Jing J et al.; Detailed restriction maps of microbial genomes are a valuable resource in genome sequencing studies but are toilsome to construct by contig construction of maps derived from cloned DNA . Analysis of genomic DNA enables large stretches of the genome to be mapped and circumvents library construction and associated cloning artifacts . We used pulsed-field gel electrophoresis purified Plasmodium falciparum chromosome 2 DNA as the starting material for optical mapping, a system for making ordered restriction maps from ensembles of individual DNA molecules . DNA molecules were bound to derivatized glass surfaces, cleaved with NheI or BamHI, and imaged by digital fluorescence microscopy . Large pieces of the chromosome containing ordered DNA restriction fragments were mapped . Maps were assembled from 50 molecules producing an average contig depth of 15 molecules and high-resolution restriction maps covering the entire chromosome . Chromosome 2 was found to be 976 kb by optical mapping with NheI, and 946 kb with BamHI, which compares closely to the published size of 947 kb from large-scale sequencing . The maps were used to further verify assemblies from the plasmid library used for sequencing . Maps generated in silico from the sequence data were compared to the optical mapping data, and good correspondence was found . Such high-resolution restriction maps may become an indispensable resource for large-scale genome sequencing projects. J Pediatr Surg, 1999 Jan, 34(1), 188 - 91; discussion 191-2 Acute chest syndrome in the postoperative sickle cell patient; Delatte SJ et al.; BACKGROUND/PURPOSE: Acute chest syndrome (ACS), a phenomenon of pulmonary sequestration in sickle cell disease (SCD) patients, is frequently missed in the postoperative SCD child . The constellation of symptoms range from fever and respiratory distress to abdominal discomfort . In its most fulminate state, the syndrome has been reported in some series to carry almost a 25% to 50% mortality rate in the postoperative patient . The incidence in pediatric patients in the era of minimally invasive surgery is unknown . METHODS: Since December 1995, 63 episodes of ACS have been documented in the nearly 500 SCD children seen at our institution . Six of 63 episodes occurred within 2 weeks after a surgical procedure under general anesthesia . During this period, 59 operations were performed by the pediatric surgery service on SCD patients with an ACS incidence of 10.2% . Careful review of the preoperative, intraoperative, and postoperative management of these patients was performed . RESULTS: All six received preoperative oxygen saturation monitoring and intravenous fluid (IVF) hydration . One half of these patients required transfusion to achieve a hemoglobin level of greater than 10 mg/dL . Documentation of intraoperative temperature, hypoxia, volume status, and hypercarbia as well as any atypical perioperative events were monitored and reviewed . All patients received postoperative oxygen supplementation and IVF hydration . Onset of ACS ranged from 1 hour to 7 days postoperatively . Only one of six was thought to be of microbial etiology (elevated mycoplasma titers), and all patients received prophylactic antibiotic and aggressive pulmonary therapy . Overall length of hospitalization was increased with an average stay of 6.1 days . There were no postsurgical ACS deaths . CONCLUSIONS: Despite close attention and avoidance of known risk factors for development of postoperative SCD complications, ACS occurred with an incidence much higher than previously reported in the literature (0.4% v 10.2%) . Interestingly, five of six cases were after laparoscopic procedures suggesting that the advantages of laparoscopy, such as reduced postoperative pain, do not extrapolate to decreased incidence of ACS. Biodegradation, 1998, 9(3-4), 301 - 10 Biotechnological possibilities for waste tyre-rubber treatment; Holst O et al.; Every year large amounts of spent rubber material, mainly from rubber tyres, are discarded . Of the annual total global production of rubber material, which amounts to 16-17 million tonnes, approximately 65% is used for the production of tyres . About 250 millions spent car tyres are generated yearly in USA only . This huge amount of waste rubber material is an environmental problem of great concern . Various ways to remediate the problem have been proposed . Among these are road fillings and combustion in kilns . Spent tyres, however, comprise valuable material that could be recycled if a proper technique can be developed . One way of recycling old tyres is to blend ground spent rubber with virgin material followed by vulcanization . The main obstacle to this recycling is bad adhesion between the crumb and matrix of virgin rubber material due to little formation of interfacial sulphur crosslinks . Micro-organisms able to break sulphur-sulphur and sulphur-carbon bonds can be used to devulcanize waste rubber in order to make polymer chains on the surface more flexible and facilitate increased binding upon vulcanization . Several species belonging to both Bacteria and Archaea have this ability . Mainly sulphur oxidizing species, such as different species of the genus Thiobacillus and thermoacidophiles of the order of Sulfolobales, have been studied in this context . The present paper will give a background to the problem and an overview of the biotechnological possibilities for solutions of waste rubber as an environmental problem, focusing on microbial desulphurization. Biodegradation, 1998, 9(3-4), 293 - 300 Technological and economic aspects of coal biodesulfurisation; Klein J; The sulfur found in coal is either part of the molecular coal structure (organically bound sulfur), is contained in minerals such as pyrite (FeS2), or occurs in minor quantities in the form of sulfate and elemental sulfur . When pyrite crystals are finely distributed within the coal matrix, mechanical cleaning can only remove part of the pyrite . It can, however, be removed by microbial action requiring only mild conditions . The process involves simple equipment, almost no chemicals, but relatively long reaction times, and treatment of iron sulfate containing process water . Different process configurations are possible, depending on the coal particle size . Coal with particle sizes of less than 0.5 mm is preferably desulfurised in slurry reactors, while lump coal (> 0.5 mm) should be treated in heaps . Investment and operating costs are estimated for different process configurations on an industrial scale . Concerning the organically bound sulfur in coal there is up to now no promising biochemical pathway for the degradation and/or desulfurisation of such compounds. Biodegradation, 1998, 9(3-4), 201 - 12 Bioenergetics of sulphate-reducing bacteria in relation to their environmental impact; Hamilton WA; The cellular physiology of the sulphate-reducing bacteria, and of other sulphidogenic species, is determined by the energetic requirements consequent upon their respiratory mode of metabolism with sulphate and other oxyanions of sulphur as terminal electron acceptors . As a further consequence of their, relatively, restricted catabolic activities and their requirement for conditions of anaerobiosis, sulphidogenic bacteria are almost invariably found in nature as component organisms within microbial consortia . The capacity to generate significant quantities of sulphide influences the overall metabolic activity and species diversity of these consortia, and is the root cause of the environmental impact of the sulphidogenic species: corrosion, pollution and the souring of hydrocarbon reservoirs. Chem Biol, 1999 Feb, 6(2), R39 - 48 How do peptide synthetases generate structural diversity? Konz D, Marahiel MA. Many low-molecular-weight peptides of microbial origin are synthesized nonribosomally on large multifunctional proteins, termed peptide synthetases . These enzymes contain repeated building blocks in which several defined domains catalyze specific reactions of peptide synthesis . The order of these domains within the enzyme determines the sequence and structure of the peptide product. J Am Pharm Assoc (Wash), 1999 Jan-Feb, 39(1), 27 - 31 Comparison of melatonin products against USP's nutritional supplements standards and other criteria; Hahm H et al.; OBJECTIVE: To evaluate and compare the quality of a sample of melatonin products, as measured by the United States Pharmacopeial Convention (USP) General Tests and Assays for Nutritional Supplements (other than Microbial Limits) and certain other tests . DESIGN: Five immediate-release, two sublingual, and two controlled-release products were randomly gathered from a health food store, groceries, and pharmacies in the Baltimore-Washington metropolitan area . MAIN OUTCOME MEASURES: Weight variation, disintegration (not applicable for controlled-release products), and drug dissolution, based on USP standards . Twelve-hour dissolution profiles were obtained from the controlled-release products . All tablets were also evaluated for friability following the USP procedure and for hardness following unofficial procedures . RESULTS: All products passed the weight variation test . Two products showed excessive friability . Three immediate-release products failed both the disintegration and the dissolution tests . One of the three products demonstrated a threefold difference in hardness . One controlled-release product released 90% of melatonin in four hours in the dissolution test; the other released 90% of its content in 12 hours . CONCLUSION: Some products showed evidence of poor formulation and/or poor quality control as indicated by excessive friability, failure to disintegrate and dissolve, and excessive variation in hardness . In vitro release profiles of the two controlled-release products were substantially different . The poor quality of some supplements should be a concern to consumers and health care providers. J Exp Med, 1999 Feb 15, 189(4), 741 - 6 Macrophage microbicidal mechanisms in vivo: reactive nitrogen versus oxygen intermediates in the killing of intracellular visceral Leishmania donovani; Murray HW et al.; To determine the relative contributions of respiratory burst-derived reactive oxygen intermediates (ROI) versus reactive nitrogen intermediates (RNI) to macrophage-mediated intracellular host defense, mice genetically deficient in these mechanisms were challenged with Leishmania donovani, a protozoan that selectively parasitizes visceral tissue macrophages . During the early stage of liver infection at wk 2, both respiratory burst-deficient gp91(phox)-/- (X-linked chronic granulomatous disease {X-CGD}) mice and inducible nitric oxide synthase (iNOS) knockout (KO) mice displayed comparably increased susceptibility . Thereafter, infection was unrestrained in mice lacking iNOS but was fully controlled in X-CGD mice . Mononuclear cell influx into infected liver foci in X-CGD and iNOS KO mice was also overtly impaired at wk 2 . However, granuloma assembly in parasitized tissue eventually developed in both hosts but with divergent effects: mature granulomas were functionally active (leishmanicidal) in X-CGD mice but inert in iNOS-deficient animals . These results suggest that (a) ROI and RNI probably act together in the early stage of intracellular infection to regulate both tissue recruitment of mononuclear inflammatory cells and the initial extent of microbial replication, (b) RNI alone are necessary and sufficient for eventual control of visceral infection, and (c) although mature granulomas have traditionally been associated with control of such infections, these structures fail to limit intracellular parasite replication in the absence of iNOS. Med Mycol, 1998, 36 Suppl 1, 194 - 206 New approaches to antifungal chemotherapy; Viviani MA et al.; The antifungal agents currently available to treat invasive fungal infections are limited in both number and usefulness . Treatment with the polyene amphotericin B (AmB), and with several azoles, in particular fluconazole and itraconazole, is the mainstay of antifungal chemotherapy . However, the clinical usefulness of these drugs is hampered by drawbacks associated with their safety and/or efficacy . There are two approaches to overcome this situation . One is to discover and develop new antifungal agents or formulations with advantages over and/or complementary to existing drugs . For this purpose, the following three categories of new drugs have been the major targets of study and development: (i) lipid formulations of polyenes, (ii) azoles (including cyclodextrin-complexes), and (iii) nonazole compounds, particularly those of microbial origin (antibiotics). Mol Microbiol, 1999 Jan, 31(1), 223 - 35 Molecular characterization of a novel peroxidase isolated from the ligninolytic fungus Pleurotus eryngii; Ruiz-Duenas FJ et al.; A haem peroxidase different from other microbial, plant and animal peroxidases is described . The enzyme is secreted as two isoforms by dikaryotic Pleurotus eryngii in peptone-containing liquid medium . The corresponding gene, which presents 15 introns and encodes a 361-amino-acid protein with a 30-amino-acid signal peptide, was isolated as two alleles corresponding to the two isoforms . The alleles differ in three amino acid residues and in a seven nucleotide deletion affecting a single metal response element in the promoter . When compared with Phanerochaete chrysosporium peroxidases, the new enzyme appears closer to lignin peroxidase (LiP) than to Mn-dependent peroxidase (MnP) isoenzymes (58-60% and 55% identity respectively) . The molecular model built using crystal structures of three fungal peroxidases as templates, also showed high structural affinity with LiP (C alpha-distance 1.2 A) . However, this peroxidase includes a Mn2+ binding site formed by three acidic residues (E36, E40 and D175) near the haem internal propionate, which accounts for the ability to oxidize Mn2+ . Its capability to oxidize aromatic substrates could involve interactions with aromatic residues at the edge of the haem channel . Another possibility is long-range electron transfer, e.g . from W164, which occupies the same position of LiP W171 recently reported as involved in the catalytic cycle of LiP. Coll Antropol, 1998 Dec, 22 Suppl, 103 - 9 Reduction of epithelial dendritic cells in keratotic lesion of oral lichen planus; Mravak-Stipetic M et al.; The number and distribution of epithelial dendritic cells (EDC) in oral mucosal lesions are variable depending on the degree of epithelial maturation/differentiation and disease activity . Localized absence of EDC might impair mucosal immunologic protection, allow microbial colonization and enhance carcinogenesis . Increased number of EDC during the early stage of oral lichen planus (OLP) suggests their increased antigen-presenting capability and immunologic activity with inflammatory reaction, but their role in the process of keratinization remains unclear . Therefore, the purpose of this study was to determine the number and distribution of EDC in 33 biopsy specimens from lesions of OLP and from 18 control specimens of leukoplakia (LPL) at sites undergoing increased keratinization . Cells were identified immunocytochemically by the presence of antigen CD68 and labeled with acid phosphatase (AP) and alpha-naphthyl acetate esterase (ANAE) techniques . Numbers of EDC were expressed per mm epithelial surface length . Significantly more EDC with prominent histoenzymatic activity of AP and ANAE were present in OLP than in LPL . Intense enzymatic activity of ANAE was expressed in EDC of OLP with hyperparakeratosis . In the lesions with increased keratinization the number of EDC was markedly reduced in OLP while in LPL remained unchanged . Reduced number and subbasal redistribution of EDC in OLP suggest diminution of immunologic reaction and disease activity but also increased tissue vulnerability to various antigen challenges. Math Biosci, 1998 Dec 15, 154(2), 87 - 102 On the coexistence of three microbial populations competing for two complementary substrates in configurations of interconnected chemostats; Thomopoulos NA et al.; We examine the question of coexistence of three microbial populations competing for two complementary rate-limiting substrates in configurations of interconnected chemostats . It is known that coexistence of two populations competing for two rate-limiting substrates is possible in a single chemostat, but coexistence is not possible when three populations are involved . We examine whether coexistence of three populations becomes possible by considering configurations of two or three interconnected chemostats, thus allowing for effects of spatial heterogeneity . Computational analysis of the model equations indicates that in the case of two chemostats coexistence is possible only for specific discrete parameter values where the system is structurally unstable and therefore the coexistence state is not practically attainable, whereas in the case of three chemostats coexistence is possible for a whole range of parameter values where the system is structurally stable and therefore the coexistence state can be realized in practice. Zh Mikrobiol Epidemiol Immunobiol, 1998 Nov-Dec, (6), 23 - 5 {Effect of technogenic pollution on bacterial biocenoses of a water reservoir}; Boiko AV et al.; The industrial pollution of a water reservoir (the Volga), both indirect and direct, not exceeding the highest admissible level, has been shown to lead to the transformation of water microbial associations . The total amount of bacteria increases simultaneously with the decrease of their specific diversity, the ratio of the members of different microbiocenoses changes towards an increase in the proportion of bacteria, resistant to stress influences, which may lead to the growth of the epidemic danger of the polluted areas of the water reservoir. Adv Biochem Eng Biotechnol, 1999, 63, 109 - 23 Production of chiral C3- and C4-units by microbial enzymes; Shimizu S et al.; Enzyme (biocatalysis) reactions display far greater specificities, such as substrate specificity, stereospecificity, regiospecificity and so on, than more conventional forms of organic reactions . Using these specificities of the enzymes, many useful compounds have been enzymatically produced . Compounds possessing C3- and C4-units with additional functional groups are promising materials for the synthesis of various useful compounds . In particular, optically active C3- and C4-synthetic units are quite important intermediates for the preparation of pharmaceuticals and fine chemicals . Microbial transformation with enzymes showing stereo-specificities have been applied to the asymmetric synthesis of optically active substances . In this article the recent works on the practical production of chiral C3- and C4-synthetic units with microbial enzymes are described. Dtsch Tierarztl Wochenschr, 1998 Dec, 105(12), 472 - 4 Forestomach motility in llamas and camels; von Engelhardt W; Major aspects of forestomach anatomy in llamas and camels are described . The pattern of forestomach motility is a succession of motoric cycles, consisting of A- and B-contraction sequences and a pause . Respective differences between llamas and camels are discussed . Observations on regulation of motility are mentioned . Occurrences and courses of rumination and eructation within the motility cycles are emphasized . Motility of the forestomach achieves a selective retention of feed particles in the forestomach; a long retention time is a prerequisite for an effective microbial digestion, especially of poor quality feed. Cas Lek Cesk, 1998 Nov 16, 137(22), 694 - 9 {Treatment of febrile neutropenia in patients with solid tumors}; Novotny J et al.; BACKGROUND: Febrile neutropenia (FN) is one of the most serious complications of anti-tumourous treatment calling for early diagnosis and intensive treatment . The objective of the trial was to recommend a standard procedure for the treatment of febrile neutropenia at their Oncological Clinic, based on analyses of attacks of febrile neutropenia and the current microbial situation . METHODS AND RESULTS: In 1995-1997 in 30 patients (24 women, 6 men) 39 attacks of febrile neutropenia were treated . The age distribution of patients was within the range of 20-68 years, the mean age being 50 years . In the group patients with breast cancer predominated (14), soft tissue sarcomas (4), colorectal carcinoma (3), other diagnoses participated with 9 episodes . The analysis of the microbial situation was based on cultivation findings made in patients with attacks of FN . For empirical treatment of FN the authors use at combined treatment piperacillin-gentamicin or sultamicillin-cefpodoxim/or ciprofloxacin . If empirical treatment fails, therapy is based on the results of cultivation and the patient's clinical condition . Growth factors are indicated for treatment only in FN complicated by mycotic infection, inflammatory pulmonary infiltrates or cardiopulmonary failure . CONCLUSIONS: The standard procedure in the treatment of FN should be broad spectrum bactericidial antibiotics . The use of growth factors is reserved for complicated episodes of FN. J Pediatr Adolesc Gynecol, 1999 Feb, 12(1), 23 - 5 Combined oral and vaginal treatment of severe vulvovaginitis during childhood; Creatsas G et al.; STUDY OBJECTIVE: To evaluate the efficacy and safety of combined oral and vaginal administration of antibiotics . DESIGN: Treatment and follow-up examination of 54 cases of severe vulvovaginitis . SETTING: Division of Pediatric and Adolescent' Gynecology, Second Department of Obstetrics and Gynecology, University of Athens, Greece . PARTICIPANTS: Girls aged 1-10 years seen at the clinic of the above-listed institution . INTERVENTIONS: Vaginal application of antibiotics . MAIN OUTCOME MEASURES: Vaginal culture and vaginoscopy . RESULTS: Treatment achieved microbial eradication in 51 of 54 patients (94%) . In most patients, relief of symptoms was achieved after 2-3 days . No adverse effects were reported . CONCLUSIONS: Treatment was highly effective and simple to administer, and no complications were observed . A further advantage of this approach is the shorter duration of treatment. Clin Cardiol, 1999 Jan, 22(1 Suppl 1), I17 - 22 Intrapericardial treatment of inflammatory and neoplastic pericarditis guided by pericardioscopy and epicardial biopsy--results from a pilot study; Maisch B et al.; From a registry of 136 patients undergoing pericardiocentesis, 14 patients with autoimmune and 15 patients with neoplastic effusions were selected . All underwent pericardioscopy, epicardial and pericardial biopsy with histologic, immunohistologic, and polymerase chain reaction/or in situ hybridization analysis for microbial DNAs and RNA . Pericardioscopy identified neoplastic effusions by the high occurrence of protrusions . Fibrin threads and layers and neovascularization were found in both groups . For identification of the inflammatory and neoplastic process, the combined analysis of the cytology of the effusion and epicardial biopsy evaluation proved to be most important . Epicardial biopsy demonstrated a slightly higher sensitivity for identifying neoplastic disorders in the pericardium than cytology alone . Pericardial biopsy was inconclusive . Intrapericardial administration of 1 g of crystalloid triamcinolone in autoreactive pericarditis prevented recurrence in 13 of the 14 cases after 3 months and in 12 of the 14 cases after 1 year . In neoplastic effusion, intrapericardial administration of 50 mg cis-platin for 24 h prevented recurrence of a hemodynamically relevant effusion after 3 months in all, and after 6-12 months in 14 of 15 patients . Mortality in neoplastic effusion due to noncardiac tumor progression was 47 and 80%, respectively, after 3 and 6 months, as can be expected in endstage neoplastic disease . This pilot study demonstrates that local drug application is feasible, life-saving, and well tolerated by the patients . It opens perspectives for local drug application in other cardiac disorders as well. Microb Ecol, 1999 Feb, 37(2), 86 - 94 Growth Rates of Marine Bacterial Isolates on Particulate Organic Substrates Solubilized by Freely Released Extracellular Enzymes; Vetter YA et al.; > Abstract Growth rates of marine bacterial isolates on particulate organic substrates were measured using a novel apparatus which restricts bacterial cells to the uptake of hydrolysate produced from particulate substrates only by enzymes that are actively released from the bacterium into the culture medium . Significant, varying growth rates were measured for four different marine bacteria, using three different, ecologically significant particulate organic substrates (preparations of amylopectin, chitin, and animal hide) . Growth rates sometimes approached but were usually lower than rates that have been reported in laboratory experiments using dissolved organic growth substrates . These results are consistent with recent model predictions and have important implications for microbial ecology and material cycling in diverse liquid-bathed environments. Eur J Epidemiol, 1998 Dec, 14(8), 749 - 54 Cancer increased after a reduction of infections in the first half of this century in Italy: etiologic and preventive implications; Mastrangelo G et al.; Two rate ratios indicating the disappearance of infections and the growth of tumours, respectively, were simultaneously plotted against the calendar years of occurrence in a period during which mortality rates were reasonably comparable to incidences . The transformation used gave upward trend time variations for infectious diseases, providing strong evidence that in Italy during the first half of this century variations in infectious diseases preceded variations in cancer . While some bacteria and viruses are known to be cancer agents, sparse studies indicate that a host's immune response to infection may destroy cancer cells . With a decreasing mortality from infectious illnesses, there may have been a reduction in the activation of immunological mechanisms against transformed cells in early phases of carcinogenesis . If cancer growth is a consequence of a lower exposure to chronic sublethal doses of microbial agents, bacterial derivates could be potentially useful in cancer chemoprevention. Ann N Y Acad Sci, 1998 Dec 30, 862, 100 - 4 Xenozoonoses and the xenotransplant recipient; Michaels M; The use of animal cells, tissues, or organs for humans is being investigated as an alternative to allotransplantation and as therapy for a broad range of disease states including diabetes, Parkinson's disease, and neurologic pain control . The risk of transmitting novel infections with these tissues, xenozoonoses, has led to much debate . It is well recognized that infections are a hazard with the use of all biologic agents . In addition, infections from human donors remain a major cause of morbidity and mortality after allotransplantation . Accordingly the potential for animal microbial agents to be pathogenic in the human recipient after xenotransplantation and be transmissible to others must be critically examined . Along with laboratory-based research, clinical trials must be conducted in a manner to evaluate the transmission of potential animal infections . Pretransplant evaluation should include discussions with the candidate and, if possible, with close contacts . Information must be provided as to the potential risks of infection and transmission to others . Behavioral modifications which can decrease spread of infections should be emphasized . Serial samples should be obtained from the patients at defined intervals and if recipients become ill . In addition, archiving samples for future evaluation is critical . Prospective evaluation will enhance the ability to define and understand the spectrum of xenogeneic infections. Ann N Y Acad Sci, 1998 Dec 13, 864, 87 - 95 Chiral alcohol synthesis with microbial carbonyl reductases in a water-organic solvent two-phase system; Shimizu S et al.; Production of chiral 4-chloro-3-hydroxybutanoate ethyl esters (CHBE) was performed through microbial asymmetric reduction of 4-chloroacetoacetate ethyl ester (CAAE) . The enzymes reducing CAAE to (R)- and (S)-CHBE were found to be produced by Sporobolomyces salmonicolor and Candida magnoliae, respectively . The enzyme of S . salmonicolor is a novel NADPH-dependent aldehyde reductase (AR) belonging to the aldo-keto reductase superfamily . When AR-overproducing Escherichia coli transformant cells or C . magnoliae cells were incubated in an organic solvent-water two-phase system, 300 or 90 mg/mL of CAAE was almost stoichiometrically converted to (R)- or (S)-CHBE (> 92% ee), respectively. Cancer Res, 1999 Jan 15, 59(2), 482 - 6 Mannosylerythritol lipid is a potent inducer of apoptosis and differentiation of mouse melanoma cells in culture; Zhao X et al.; Malignant melanomas are tumors that are well known to respond poorly to treatment with chemotherapeutic reagents . We report here that mannosylerythritol lipid (MEL), an extracellular glycolipid from yeast, markedly inhibited the growth of mouse melanoma B16 cells in a dose-dependent manner . Exposure of B16 cells to MEL at 10 microM and higher concentrations caused the condensation of chromatin, DNA fragmentation, and sub-G1 arrest, all of which are hallmarks of cells that are undergoing apoptosis . Analysis of the cell cycle also suggested that both the MEL-mediated inhibition of growth and apoptosis were closely associated with growth arrest in the G1 phase . Moreover, MEL exposure stimulated the expression of differentiation markers of melanoma cells, such as tyrosinase activity and the enhanced production of melanin, which is an indication that MEL triggered both apoptotic and cell differentiation programs . Forced expression of Bcl-2 protein in stably transformed B16 cells had a dual effect: it interfered with MEL-induced apoptosis but increased both tyrosinase activity and the production of melanin as compared with these phenomena in vector-transfected MEL-treated control B16 cells . These results provide the first evidence that growth arrest, apoptosis, and the differentiation of mouse malignant melanoma cells can be induced by a microbial extracellular glycolipid. J Periodontol, 1998 Dec, 69(12), 1382 - 91 Periodontitis-associated marker bacteria in an urban North American patient population: application of a commercial immunoassay; Eggert FM et al.; We used an immunoassay to demonstrate marker organisms (Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans) in 3 private practice populations (F-ME periodontist, 55 patients; MHM periodontist, 179 patients; and EWM general dentist, 19 patients) . Occurrence of the marker organisms involves the whole oral environment, not just individual sites, as shown by close correlation between presence of the marker organisms in 2 independent sites/samples within a single mouth . Presence of the marker P . gingivalis (and P . intermedia) relates closely to periodontal pocketing while presence of A . actinomycetemcomitans does not have this pocket-associated characteristic . There was no significant relationship between presence of the marker organisms and the number of teeth in a mouth, and in the periodontal practice patients there was no significant effect of gender on occurrence of the marker organisms . A . actinomycetemcomitans and the other 2 markers were found over the entire age range (12 to 75) of our patients . Regular periodontal treatment reduced occurrence of all marker organisms and increased the frequency of marker-negative patients and sites . Occurrence of the marker organisms above immunoassay threshold levels appears to represent how receptive a patient is to each individual organism . Most patients appear receptive to the presence of P . intermedia whether treated or not . Significantly fewer patients who underwent regular treatment show the presence of P . gingivalis or A . actinomycetemcomitans when compared to untreated patients . Diagnostic application of microbial markers requires ongoing clinical assessment of patients and careful clinical judgment . 1391. Appl Environ Microbiol, 1999 Feb, 65(2), 795 - 801 Changes in bacterial and eukaryotic community structure after mass lysis of filamentous cyanobacteria associated with viruses; van Hannen EJ et al.; During an experiment in two laboratory-scale enclosures filled with lake water (130 liters each) we noticed the almost-complete lysis of the cyanobacterial population . Based on electron microscopic observations of viral particles inside cyanobacterial filaments and counts of virus-like particles, we concluded that a viral lysis of the filamentous cyanobacteria had taken place . Denaturing gradient gel electrophoresis (DGGE) of 16S ribosomal DNA fragments qualitatively monitored the removal of the cyanobacterial species from the community and the appearance of newly emerging bacterial species . The majority of these bacteria were related to the Cytophagales and actinomycetes, bacterial divisions known to contain species capable of degrading complex organic molecules . A few days after the cyanobacteria started to lyse, a rotifer species became dominant in the DGGE profile of the eukaryotic community . Since rotifers play an important role in the carbon transfer between the microbial loop and higher trophic levels, these observations confirm the role of viruses in channeling carbon through food webs . Multidimensional scaling analysis of the DGGE profiles showed large changes in the structures of both the bacterial and eukaryotic communities at the time of lysis . These changes were remarkably similar in the two enclosures, indicating that such community structure changes are not random but occur according to a fixed pattern . Our findings strongly support the idea that viruses can structure microbial communities. Appl Environ Microbiol, 1999 Feb, 65(2), 718 - 23 Diversity of arbuscular mycorrhizal fungus populations in heavy-metal-contaminated soils; Del Val C et al.; High concentrations of heavy metals have been shown to adversely affect the size, diversity, and activity of microbial populations in soil . The aim of this work was to determine how the diversity of arbuscular mycorrhizal (AM) fungi is affected by the addition of sewage-amended sludge containing heavy metals in a long-term experiment . Due to the reduced number of indigenous AM fungal (AMF) propagules in the experimental soils, several host plants with different life cycles were used to multiply indigenous fungi . Six AMF ecotypes were found in the experimental soils, showing consistent differences with regard to their tolerance to the presence of heavy metals . AMF ecotypes ranged from very sensitive to the presence of metals to relatively tolerant to high rates of heavy metals in soil . Total AMF spore numbers decreased with increasing amounts of heavy metals in the soil . However, species richness and diversity as measured by the Shannon-Wiener index increased in soils receiving intermediate rates of sludge contamination but decreased in soils receiving the highest rate of heavy-metal-contaminated sludge . Relative densities of most AMF species were also significantly influenced by soil treatments . Host plant species exerted a selective influence on AMF population size and diversity . We conclude based on the results of this study that size and diversity of AMF populations were modified in metal-polluted soils, even in those with metal concentrations that were below the upper limits accepted by the European Union for agricultural soils. Br Poult Sci, 1998 Dec, 39(5), 612 - 21 Strategies to improve the nutritive value of rice bran in poultry diets . IV . Effects of addition of fish meal and a microbial phytase to duckling diets on bird performance and amino acid digestibility; Martin EA et al.; 1 . Ducklings were given diets with vegetable protein (VP) and 0 or 600 g rice bran/kg; fish meal (60 g/kg) and a phytase (+, -) were added to the diets (VP + AP) . An additional 40 g soyabean meal/kg was added to the diet with rice bran (VP ++) . Amino acid digestibility and mineral retention were measured in the lower ileum of ducklings killed at 23 d of age . Acid insoluble ash was used as an inert marker . Trypsin and amylase activities were also measured and weights of the pancreas and small intestine recorded at slaughter . 2 . Addition of soyabean meal (VP ++) to the diet with rice bran improved growth rate and food intake compared to the diet without (VP) and gave the same food intake and growth rate as the comparable basal diet (VP) without rice bran . Fish meal improved growth rate on the diets without rice bran and improved food intake on this diet (VP + AP) . Rice bran depressed growth rate and food conversion ratio (FCR); protein source affected growth rate, food intake and FCR; phytase increased food intake only . There were several interactions . 3 . Determined total amino acid composition of the diets appeared to meet the essential amino acid requirements of ducklings . Rice bran depressed the ileal digestibility of virtually all amino acids and phytase had no direct effect, although there were interactions . Fish meal addition to diets with rice bran improved the apparent digestibility of several essential amino acids as well as that of dry matter and crude protein . 4 . Ileal retention of some minerals and tibia ash content were reduced by rice bran . Fish meal and phytase inclusion increased P retention and ash in tibia . 5 . Higher intestinal trypsin activity and increased pancreas size were seen in ducklings on diets with rice bran compared to those without . Intestinal amylase activity was reduced in ducklings given rice bran, probably because of its low starch content . 6 . The stimulating effect of fish meal on duckling performance was probably caused in part by the improvement in the digestibility of some amino acids . The addition of small amounts of minerals in fish meal may have increased mineral retention . Phytase gave benefits anticipated from our previous work, but also improved lysine and threonine digestibility in diets containing vegetable protein only. Cancer Biochem Biophys, 1998 Nov, 16(4), 375 - 85 The instability of polyhydroxylated aromatic protein tyrosine kinase inhibitors in the presence of manganese; Ramdas L et al.; Inhibition of the tyrosine kinase activity of Src by forty-three different compounds from five chemical families (cinnamic acid, salicylic acid, phenol, coumarin and flavonoid derivatives) representing plant and microbial secondary metabolites were studied in the presence of MgCl2 versus MnCl2 . Within each chemical family, compounds containing multiple hydroxyl substituents demonstrated the greatest inhibitor potency . The ortho-substituted dihydroxy compounds were the most inhibitory . Except for the flavonoids, inhibition was higher in the presence of manganese compared to that observed with magnesium . UV-Vis spectra, HPLC, and mass spectrometric analyses demonstrate that manganese catalyzed the oxidation of these compounds . The general instability of such compounds, especially in the presence of manganese, and the associated problems it causes in the use of such compounds for developing selective protein tyrosine kinase inhibitors, is discussed. Br J Ophthalmol, 1998 Nov, 82(11), 1272 - 5 Disposable contact lens use as a risk factor for microbial keratitis; Radford CF et al.; AIMS: A case-control study was performed to evaluate soft contact lens (SCL) wear modality as a risk factor for microbial keratitis . METHODS: Contact lens wearers presenting as new patients to Moorfields Eye Hospital accident and emergency department during a 12 month period completed a self administered questionnaire detailing demographic data and contact lens use habits . Cases were patients with a clinical diagnosis of SCL related microbial keratitis . Controls were SCL users attending with disorders unrelated to contact lens wear . Odds ratios (estimates of relative risks) and 95% confidence limits (CL) were calculated through multivariable logistic regression analysis . RESULTS: There were 89 cases and 566 controls . A substantially increased risk with 1-4 weekly disposable SCL compared with non-disposable SCL was identified among both daily wear (DW) (odds ratio = 3.51, 95% CL 1.60-7.66, p = 0.002) and extended wear (odds ratio 4.76, 95% CL 1.52-14.87, p = 0.007) users after adjustment for demographic, lens use and hygiene variables . Other significant factors among DW users were "occasional" overnight use, use of chlorine based (as opposed to other chemical) systems in combination with poor storage case hygiene, and irregular disinfection . CONCLUSION: Properties of some disposable SCL may be partly responsible for these excess risks . It is also possible, however, that this finding is largely a reflection of widespread complacency among patients and practitioners with respect to disposable SCL fitting and use. Br J Nutr, 1998 Oct, 80(4), 371 - 9 Transfers of N metabolites across the ovine liver in response to short-term infusions of an amino acid mixture into the mesenteric vein; Lobley GE et al.; The effect of acute (4.5 h) infusions into the mesenteric vein of an amino acid (AA) mixture, which simulated the composition of rumen microbial protein, on net transfers of NH3, urea and total AA across the portal-drained viscera (PDV) and liver in the ovine has been examined . Four wether sheep were surgically prepared with vascular catheters across the PDV and liver (Lobley et al . 1995) and were offered a basal diet of 1000 g grass pellets/d (approximately 1.4 x energy maintenance) . Each animal was infused at weekly intervals with one of four dilutions of the AA mixture . These dilutions provided 0.44, 0.88, 1.32 and 1.84 mmol AA-N/min infused, the lowest of which approximately doubled the net absorption of AA-N from the basal diet . Animals were treated with heparin to allow continuous collection of blood by peristaltic pump for 2 h preceding, and between 0.5-2.5 and 2.5-4.5 h after, the start of the AA infusions . Blood flow in the hepatic artery increased (100 v . 208 g/min; P = 0.002) in response to AA infusion, while hepatic portal venous flow decreased (2090 v . 1854 g/min; P = 0.006) . The AA infusion also stimulated O2 uptake by the PDV (P < 0.001) and liver (P = 0.016) . Absorption across the PDV and hepatic removal of NH3 were unchanged between basal and amino acid infusion conditions . Urea-N removal across the PDV was unaltered, but hepatic production increased (P < 0.001) with level of AA infusion . During infusions, net appearance of AA across the PDV was below the theoretical level . This may have been due to inhibition of AA uptake from the small intestine, and/or increased removal by the digestive tract of AA from the systemic circulation associated with greater arterial concentrations . Hepatic extraction of AA increased with level of infusion, both for total AA and those included in the infusate . Total hepatic urea-N production tended towards a maximum (estimated as 2 mumol N/g liver wet weight per min) . The AA removed by the liver and not used for ureagenesis remained similar (170 mumol AA-N/min) between basal and AA infusions . This was presumed available for anabolic purposes (mainly synthesis of export proteins) . The proportion of net AA-N appearance (absorption plus infused) across the PDV removed by the liver declined from 0.71 to 0.53 between basal and AA infusions . In contrast to findings from cattle (Wray-Cahen et al . 1997), increased AA infusion did not alter the net removal of glutamine across the liver . This may reflect differences between the studies in NH3: AA-N absorbed . Further differences between the cattle study and the current findings may relate to the different physiological state (pregnancy v . growth), which may alter the partition of AA between anabolic and catabolic fates. Science, 1999 Jan 29, 283(5402), 686 - 9 Acetogenesis from H2 plus CO2 by spirochetes from termite guts; Leadbetter JR et al.; Pure cultures of termite gut spirochetes were obtained and were shown to catalyze the synthesis of acetate from H2 plus CO2 . The 16S ribosomal DNA sequences of two strains were 98 percent similar and were affiliated with those of the genus Treponema . However, neither was closely related to any known treponeme . These findings imply an important role for spirochetes in termite nutrition, help to reconcile the dominance of acetogenesis over methanogenesis as an H2 sink in termite hindguts, suggest that the motility of termite gut protozoa by means of attached spirochetes may be based on interspecies H2 transfer, and underscore the importance of termites as a rich reservoir of novel microbial diversity. J Public Health Med, 1998 Dec, 20(4), 386 - 95 Impact of infection on mortality and hospitalization in the North East of England; Wilson D et al.; BACKGROUND: Current modes of presentation of mortality and hospitalization data, based on codes in Chapter 1 of the International Classification of Diseases (ICD), hide the true importance of infection and other microbial diseases (infections) . Our aim was to produce a new aggregation of ICD-9 to estimate their true impact . METHODS: ICD-9 codes for infections, irrespective of ICD-9 chapter, were extracted to form the new aggregation . We reanalysed routine mortality (1979-1983 and 1989-1993) and hospital finished consultant episode data (FCEs) (1989-1993) in the area of the former Northern Regional Health Authority (population approximately 3 million) using the new aggregation of codes . This area is in the North East of England . Age- and sex-specific rates of death and FCE from infection were calculated using mid-1981 and mid-1991 population estimates . RESULTS: Using ICD-9 Chapter 1 codes, 839 (0.4 per cent) deaths in 1989-1993 were classified as due to infection, compared with 12655 (6.7 per cent) with the new aggregation . In 1979-1983, 10.3 per cent of all deaths were due to infection . The highest rates of infection death were in the oldest age groups and infants . FCEs for infections were 1.2 per cent using ICD-9 Chapter 1 codes, but 5.4 per cent using the new aggregation . The highest rates of infection FCEs were in infants . Most infection deaths and hospitalizations were for respiratory disorders . Using the new aggregation, infection moved from the 13th ranking cause of death to the third ranking cause; and from the 15th ranking cause of hospitalization to the 10th . CONCLUSIONS: The usual method of presenting data coded by ICD-9 chapters greatly understates the contribution of infection to morbidity and mortality and may mislead policy makers assessing the priority to be given to infections. Int J Prosthodont, 1998 Sep-Oct, 11(5), 433 - 41 Microbial colonization of the peri-implant environment and its relevance to long-term success of osseointegrated implants; Ellen RP; PURPOSE: This article provides a critical examination of the literature on the colonization of the peri-implant environment and its impact on clinically significant infection, in the context of a comparison with the microbial etiology of periodontitis . MATERIALS AND METHODS: Previous journal article bibliographies and MEDLINE searches provided comprehensive access to current literature on this topic . References that provided significant or novel advancements in knowledge were included in this review . Since it was prepared for a workshop that would examine this issue critically, this review offers provocative commentary . RESULTS: There are many similarities in peri-implant and periodontal microbiology, both in health and in infection leading to progressive deterioration . Periodontal pockets serve as reservoirs for the colonization of implants by periodontal pathogens in partially edentulous patients . Implant design and material composition affect the colonization of implant surfaces . Infections around implants can be treated by similar strategies used for periodontitis . Investigators are beginning to adopt research designs used in periodontology to study the pathogenesis and treatment of peri-implant infections . Research in this area is impeded by the lack of surrogate variables for crestal bone resorption . CONCLUSION: Some implants fail as a result of infection, but the frequency of failure by infection or any other cause is unknown . This paper suggests areas where much more additional research is needed, including critical consideration of strategies that have led to the past few decades' advancements in the pathogenesis of periodontitis. Am J Respir Cell Mol Biol, 1999 Feb, 20(2), 219 - 27 Brief exposure to 95% oxygen alters surfactant protein D and mRNA in adult rat alveolar and bronchiolar epithelium; Aderibigbe AO et al.; Surfactant protein D (SP-D), which has structural homology to C-type lectin binding regions, may play a role in host defense and has no known surfactant function . Because other surfactant proteins have been shown to be increased after prolonged periods of hyperoxia, we sought to evaluate the early effects of hyperoxia (95% O2) on expression of SP-D in the adult male rat lung . Animals were exposed to air or to 12, 36, or 60 h of 95% O2 . Northern blot analysis of total lung RNA revealed marked SP-D mRNA increases at 12 h 95% O2 compared with air-exposed controls, with decreasing expression to near that of air-exposed animals by 60 h . Semiquantitative in situ RNA hybridization demonstrated parallel results, with increased numbers of labeled alveolar epithelial (AE) and bronchiolar epithelial (BE) cells at 12 h and increased intensity of labeled alveolar cells, compared with air-exposed controls . After 60 h of exposure to 95% O2, mRNA label intensity in AE and BE was decreased to levels near those seen in air-exposed animals . In contrast, Western blotting showed a decline in total lung SP-D with 95% O2 exposure, beginning at 12 h and continuing at 36 and 60 h, respectively . Semiquantitative immunohistochemistry demonstrated a decline in AE labeling parallel to the total lung Western blot results, but labeled total BE cell numbers increased (P = 0.10) . Hyperoxia had differential effects on SP-D abundance in AE and BE cells, and therefore may influence the availability of SP-D to bind microbial pathogens in the airways depending on cell type and location. J Food Prot, 1999 Jan, 62(1), 10 - 5 Influence of various commercial packaging conditions on survival of Escherichia coli O157:H7 to irradiation by electron beam versus gamma rays; Lopez-Gonzalez V et al.; Irradiation of ground beef patties inoculated with the organism Escherichia coli O157:H7 was performed either by gamma rays from a cobalt 60 source or by electron beam generated by a linear accelerator . Patties were packaged in one of the following materials: nylon/polyethylene bags, Saran/polyester/polyethylene bags (PM2), or Saran overwrap with a Styrofoam tray inside . Bags were sealed in air or under vacuum and were irradiated at either 5 or -15 degrees C . Average D10 values (dose required to inactivate 90% of a microbial population) ranged from 0.27 to 0.63 kGy, depending on the conditions . Overall, higher D10 values (P<0.0001) were obtained upon irradiation at -15 degrees C as compared with 5 degrees C . Cells inoculated in samples packaged in PM2 had the highest D10 values, but only if irradiated by electron beam at -15 degrees C (P<0.001) . Since PM2 had the lowest oxygen permeability rate and since the temperature was too low for radicals to migrate easily, these conditions may have minimized the effect of oxygen- and water-derived radicals on microbial survival . Irradiation by gamma rays resulted in higher D10 values (P<0.047) than irradiation by electron beam, with the highest values being observed at -15 degrees C . Differences may be attributed to dose rate (1.0 kGy/h for gamma, 17 kGy/min for electron beam) since it is possible that, at low dose rates, microbial enzymes may have more time to repair damage to the cell due to irradiation, resulting in higher D10 values. J Parasitol, 1998 Dec, 84(6), 1274 - 7 Beneficial effect of selenium supplementation during murine infection with Trypanosoma cruzi; Davis CD et al.; Selenium (Se) has been shown to function as an antioxidant that may enhance immunity during microbial infection . To investigate the effect of elevated levels of Se on the course of experimental Chagas' disease, 5 groups of C3HeB/FeJ mice were infected with 10(3) bloodform trypomastigotes of a Brazil strain of Trypanosoma cruzi while receiving supplements of 0 ppm, 2 ppm, 4 ppm, 8 ppm, or 16 ppm Se as sodium selenate in drinking water . After 64 days of infection, survival ranged from 0 to 60%, with groups receiving 4 ppm and 8 ppm Se exhibiting 60% survival and the group without Se exhibiting 0% survival . In addition, parasitemia levels of mice supplemented with Se were significantly lower (P<0.01) than in nonsupplemented mice . The results of the present study suggest that Se supplementation does have a beneficial effect during murine infection with T . cruzi, resulting in decreased parasitemias and increased longevity. Cell Immunol, 1999 Jan 10, 191(1), 49 - 59 An inhibitor of CD28-CD80 interactions impairs CD28-mediated costimulation of human CD4 T cells; Fine JS et al.; We have identified and characterized a microbial extract-derived inhibitor of T cell CD28-dependent costimulation, NP1835-2, utilizing an in vitro system in which anti-human CD3 antibody and a human CD80-Ig fusion protein are immobilized on protein A-coated microspheres . This system is CD28-CD80-dependent, as judged by the specific ability of anti-CD80 antibody or cytotoxic T lymphocyte antigen-4-Ig to block human CD4 T cell responses . Activation of CD4 T cells in this system in presence of NP1835-2 resulted in a concentration-dependent inhibition of T cell proliferation (IC50 of 1-4 microg/ml), surface activation marker expression, and the production of many T cell cytokines, with the exception of TGFbeta . Impairment of T cell activation correlated with a blockade of cell cycle progression at G0/G1 and was only partly restored by addition of 100 U/ml IL-2 . No inhibition by NP1835-2 of T cell proliferation stimulated by plate-bound anti-CD3 antibody, phorbol 12-myristate 13-acetate + A23187, or P815 cells expressing the costimulatory molecule CD58 was observed . NP1835-2 was unable to modulate anti-IgM-stimulated B cell proliferation or LPS-induced monocyte activation . Suboptimal concentrations of NP1835-2 and cyclosporin together were able to impair T cell activation in an additive fashion . NP1835-2 was also able to inhibit the primary human MLR . These data indicate that NP1835-2 may belong to a class of molecules capable of selectively impairing CD28-mediated T cell costimulation and suggest its potential usefulness in the treatment of a variety of T cell-dependent diseases . Moreover, NP1835-2 may serve as a useful probe for investigating the mechanisms involved in T cell nonresponsiveness . Cell Immunol, 1999 Jan 10, 191(1), 20 - 5 Tetanus toxin impairs accessory and secretory functions in interferon-gamma-treated murine macrophages; Pitzurra L et al.; Tetanus neurotoxin (TT), a product of microbial origin, acts as a zinc endopeptidase on vesicle-associated membrane proteins (VAMP) . We have demonstrated that TT displays inhibitory effects on secretory and accessory functions in the murine macrophage (Mphi) cell line GG2EE . Nitric oxide (NO) secretion was decreased when interferon (IFN)-gamma-pretreated GG2EE Mphis were coincubated with a fungal costimulus (SMP200) and TT . When heat-inactivated TT was used this effect was not evident . The TT-mediated phenomenon was dose-dependent and specific since, under the same experimental conditions, it did not affect interleukin-6 or tumor necrosis factor-alpha secretion . Furthermore, IFN-gamma-induced major histocompatibility complex class II molecule expression and GG2EE accessory function, assessed by SMP200-stimulated lymphoproliferation, were also inhibited by TT . Such inhibition was incomplete, in line with our previous results showing that TT partially cleaves VAMP proteins in murine M&phi; . Mycoses, 1998 Nov, 41(9-10), 383 - 8 Airborne fungi and their secondary metabolites in working places in a compost facility; Fischer G et al.; The present study investigates in detail the exposure to airborne fungal spores in working places in compost facilities . The fungal species composition in the air is compared with the spectrum of microbial metabolites with regard to the physiological properties of different fungal species . The results indicate that the spectrum of microbial volatile organic compounds (MVOCs) and the production of mycotoxins can be specific for certain species . In addition to the pathogenic and allergological relevance, the fungi may have different toxicological health impacts. Infect Immun, 1999 Feb, 67(2), 946 - 53 Human intestinal M cells display the sialyl Lewis A antigen; Giannasca PJ et al.; The biochemical features that distinguish human M cells from other intestinal epithelial cell types are important for understanding microbial pathogenesis and for targeting vaccines to the mucosal immune system . We applied a large panel of carbohydrate-specific monoclonal antibodies and lectins to Peyer's patch and cecum biopsy specimens from three normal individuals and a patient with inflammatory bowel disease . The results show that human M-cell glycosylation patterns are distinct from those of other species examined and that human M cells preferentially display the sialyl Lewis A antigen . This carbohydrate epitope is also present in a small subpopulation of enterocytes in the follicle-associated epithelium and in goblet cell mucins. Infect Immun, 1999 Feb, 67(2), 504 - 12 Genetic and physiologic characterization of urease of Actinomyces naeslundii; Morou-Bermudez E et al.; Ammonia production from urea by ureolytic oral bacteria is believed to have a significant impact on oral health and the ecological balance of oral microbial populations . In this study we cloned and characterized the urease gene cluster of Actinomyces naeslundii, which is one of the pioneer organisms in the oral cavity and a significant constituent of supragingival and subgingival dental plaque in children and adults . An internal fragment of the ureC gene of A . naeslundii WVU45 was initially amplified by PCR with degenerate primers derived from conserved amino acid sequences of the large catalytic subunit of urease in bacteria and plants . The PCR product was then used as a probe to identify recombinant bacteriophages carrying the A . naeslundii urease gene cluster and roughly 30 kbp of flanking DNA . Nucleotide sequence analysis demonstrated that the gene cluster was comprised of seven contiguously arranged open reading frames with significant homologies at the protein and nucleotide sequence levels to the ureABCEFGD genes from other organisms . By using primer extension, a putative transcription initiation site was mapped at 66 bases 5' to the start codon of ureA . A urease-deficient strain was constructed by insertion of a kanamycin resistance determinant within the ureC gene via allelic replacement . In contrast to the wild-type organism, the isogenic mutant was unable to grow in a semidefined medium supplemented with urea as the nitrogen source and was not protected by the addition of urea against killing in moderately acidic environments . These data indicated that urea can be effectively utilized as a nitrogen source by A . naeslundii via a urease-dependent pathway and that ureolysis can protect A . naeslundii against environmental acidification at physiologically relevant pH values . Therefore, urease could confer to A . naeslundii critical selective advantages over nonureolytic organisms in dental plaque, constituting an important determinant of plaque ecology. Curr Opin Rheumatol, 1999 Jan, 11(1), 11 - 6 Molecular approaches for identification of infectious agents in Wegener's granulomatosis and other vasculitides; Nikkari S et al.; The primary symptoms of many vasculitides resemble those of infectious diseases . Patients with Wegener's granulomatosis usually seek medical care for respiratory tract symptoms resembling those caused by infection or allergy . In addition, vasculitis is a well-documented manifestation of infection by some known microbial agents . There have been relatively few controlled studies, however, seeking to identify infectious agents as the triggering factors in systemic vasculitides . Molecular methods offer powerful approaches for the identification of infectious agents in diseases of previously unknown origin . These methods include broad-range amplification of microbial nucleic acid sequences and comparative or subtractive methods, such as differential display and representational difference analysis . Host gene expression profiles (using DNA-chip technology) may also provide clues as to the possible infectious cause of an idiopathic disease . Furthermore, the application of molecular methods may reveal pathologic mechanisms and novel therapeutic strategies for the vasculitides. Biotechniques, 1999 Jan, 26(1), 134 - 8, 140-1 General method for plasmid construction using homologous recombination; Raymond CK et al.; We describe a general method for plasmid assembly that uses yeast and extends beyond yeast-specific research applications . This technology exploits the homologous recombination, double-stranded break repair pathway in Saccharomyces cerevisiae to join DNA fragments . Synthetic, double-stranded "recombination linkers" were used to "subclone" a DNA fragment into a plasmid with > 80% efficiency . Quantitative data on the influence of DNA concentration and overlap length on the efficiency of recombination are presented . Using a simple procedure, plasmids were shuttled from yeast into E . coli for subsequent screening and large-scale plasmid preps . This simple method for plasmid construction has several advantages . (i) It bypasses the need for extensive PCR amplification and for purification, modification and/or ligation techniques routinely used for plasmid constructions . (ii) The method does not rely on available restriction sites, thus fragment and vector DNA can be joined within any DNA sequence . This enables the use of multifunctional cloning vectors for protein expression in mammalian cells, other yeast species, E . coli and other expression systems as discussed . (iii) Finally, the technology exploits yeast strains, plasmids and microbial techniques that are inexpensive and readily available. J Eur Acad Dermatol Venereol, 1998 Sep, 11 Suppl 1, S8 - 12; discussion S28-9 Topical therapy in acne; Gollnick H et al.; The majority of acne patients will receive a topical treatment either as monotherapy or in combination with a systemic drug therapy depending on the severity of the disease . The currently available topical agents affect at least one of the four main pathogenetic factors responsible for the development of acne, i.e . hyperkeratosis, microbial colonization, immune response and inflammation . Retinoids, azelaic acid, benzoyl peroxide and topical antibiotics represent the spectrum of the established and proven topical agents . Presumably, antiandrogenic agents will soon be available for topical use to treat the important factor of seborrhea . In general, by combining topical agents, their potency can be enhanced and toxicity diminished . Unfortunately, bacterial resistances are beginning to emerge as a significant problem. Rheum Dis Clin North Am, 1998 Nov, 24(4), 753 - 70 Features of spondyloarthritis around the world; Lau CS et al.; This article elucidates the prevalence and pathogenic roles of the MHC and microbial infections and clinical features and treatment of SpA across different populations from the arctic and subarctic regions to Central America, Asia, and Africa . Preliminary evidence suggests significant genetic and environmental influences on the onset and presentation of SpA, particularly AS, in these populations, which are different than those reported in white Caucasians; however, community surveys and longitudinal and case control studies are difficult to undertake in many of the developing countries . Thus, most of the currently available data have been devised from short-term and retrospective studies and should be treated with caution . Differences in referral and follow-up practices and the availability of rheumatology expertise and relevant resources may explain some of the differences observed in the populations discussed in this article . Furthermore, widely accepted criteria for the classification of SpA may not be applicable to non-Caucasians and need to be evaluated in these subjects . With gradual improvement in the economic status in many of the developing countries in Asia and Africa, it is hoped that with improvement in medical services, more physicians and specialty clinics in rheumatology, and changing referral patterns, better documentation of the various aspects of different SpA can be achieved . Future research should focus on the evaluation of specific risk or protective factors in population groups to better delineate the relative importance of genetic and environmental effects in the pathogenesis of SpA. J Dairy Sci, 1998 Dec, 81(12), 3350 - 69 Modeling ruminal digestibility of carbohydrates and microbial protein flow to the duodenum; Firkins JL et al.; Carbohydrates are the major source of energy for dairy cows and for microbial protein synthesis in the rumen . The prediction of ruminal carbohydrate digestibility and of the flow of microbial protein to the small intestine is difficult because of the variability among various feeds in the kinetics of digestion and passage of neutral detergent fiber and starch . Disappearance of fiber and starch in vitro or in situ and gas production in vitro have been extensively evaluated, improved, and reviewed . Similarly, markers and models to measure ruminal passage rate have been extensively researched and improved . Sources of variation and decreased accuracy for these techniques are discussed . Variation and potential errors also remain for the prediction of microbial protein flow to the duodenum using in vivo procedures . However, when in vivo results were accumulated into a database, microbial N flow to the duodenum over a wide range of conditions could be predicted accurately by intake of net energy for lactation or by dry matter intake and percentage of neutral detergent fiber in the diet . Although evaluation of feeding interactions and specific dietary limitations for microbial protein production in the rumen are possible with some models but not with this regression approach, mechanistic models need further validation and more accurate rate constants for improved accuracy over a wide range of conditions. J Dairy Sci, 1998 Dec, 81(12), 3248 - 58 Glucose metabolism and milk yield of cows infused abomasally or ruminally with starch; Knowlton KF et al.; The effect of ruminal or abomasal starch infusion on milk yield and glucose metabolism of early lactation cows was measured . Four cows were continuously infused in the rumen or abomasum with partially hydrolyzed starch (1500 g/d) or were not infused (control) for three 14-d periods during wk 4 to 12 postpartum . Milk yield averaged over 40 kg/d throughout the experiment . Milk and milk lactose yields tended to increase when starch was infused and DMI was decreased, regardless of the site of infusion . Starch infusion increased mean insulin concentration and tended to decrease the concentration of serum nonesterified fatty acids . Ruminal starch infusion did not affect glucose irreversible loss rate but tended to increase glucagon concentration and decrease glucose oxidation . The increased milk yield that occurred when starch was infused ruminally relative to the milk yield of control cows could be a result of increased microbial protein supply or increased energy availability . Compared with ruminal starch infusion, abomasal starch infusion tended to increase the irreversible loss rate of glucose and to increase glucose oxidation . Abomasal infusion tended to increase plasma insulin concentration and to decrease the nonesterified fatty acid concentration relative to ruminal infusion . Infusion of starch abomasally resulted in increases of most uses of glucose, including milk lactose production, glucose oxidation, and the possible storage of glucose as body fat, which indicates that the early lactation dairy cow has a greater capacity for glucose metabolism than is provided by voluntary feed intake of average diets, but that not all available glucose is partitioned to the mammary gland . These data should be useful in testing current concepts and equations in nutritional and metabolic models of dairy cattle. J Dairy Sci, 1998 Dec, 81(12), 3214 - 21 Effect of a Saccharomyces cerevisiae culture on nutrient digestion in lactating dairy cows; Doreau M et al.; The digestive effects of a Saccharomyces cerevisiae culture were investigated . Four cows in early lactation that were fitted with ruminal and duodenal cannulas were used in a crossover design . The diet, which consisted of 60% corn silage and 40% concentrates, was supplemented or not supplemented with a daily dose of 50 g of premix containing 0.5 g of S . cerevisiae (6 x 10(8) cfu/g of premix) . Total and ruminal digestibilities of organic matter, duodenal flows of nonmicrobial and microbial N, solid and liquid turnover rates, ruminal protozoal numbers, pH, ammonia N and volatile fatty acid concentrations, and concentrations of some plasma metabolites were not modified by the addition of S . cerevisiae . Ruminal dry matter content increased when S . cerevisiae was supplemented to the diet . In situ ruminal degradabilities of dry matter and neutral detergent fiber from corn stalk and of N from soybean meal were not modified; degradability of acid detergent fiber from corn stalk increased (32.5% vs . 26.3%) with the addition of S . cerevisiae . A short-term increase in N degradation was observed after 4 and 8 h of incubation . This experiment showed no effect of S . cerevisiae on most quantitative digestive events; however, a positive transitory postprandial effect on some parameters of microbial activity was observed. J Dairy Sci, 1998 Dec, 81(12), 3182 - 213 Effects of rumen-undegradable protein on dairy cow performance: a 12-year literature review; Santos FA et al.; In order to integrate and analyze knowledge on the use of protein supplements and protein nutrition of lactating dairy cows, we compiled a review of 108 studies published throughout the world, but principally in the Journal of Dairy Science between 1985 and 1997 . In 29 comparisons from 15 metabolism trials, soybean meal was replaced by high amounts of rumen undegradable protein (RUP) as a supplement; the benefits were not consistently observed for flow to the duodenum, essential amino acids, or lysine and methionine . High RUP diets resulted in decreased microbial protein synthesis in 76% of the comparisons . However, fish meal provided a good balance of lysine and methionine when calculated as a percentage of total essential amino acids . In 127 comparisons from 88 lactation trials that were published from 1985 to 1997, researchers studied the effects of replacing soybean meal with high RUP sources, such as heated and chemically treated soybean meal, corn gluten meal, distillers grains, brewers grains, blood meal, meat and bone meal, feather meal, or blends of these sources; milk yield was significantly higher in only 17% of the comparisons . Fish meal and treated soybean meal accounted for most of the positive effects on milk yield from RUP; corn gluten meal resulted in mostly negative results . The percentage of fat in milk was depressed more by fish meal than by other RUP sources . Protein percentage was decreased in 28 comparisons and increased in only 6 comparisons, probably reflecting the decrease in microbial protein synthesis, as was observed for diets high in RUP . The data strongly suggest that increased RUP per se in dairy cow diets, which often results in a decrease in RDP and a change in absorbed AA profiles, does not consistently improve lactational performance. Biochemistry, 1999 Jan 5, 38(1), 247 - 56 Two short-chain dehydrogenases confer stereoselectivity for enantiomers of epoxypropane in the multiprotein epoxide carboxylating systems of Xanthobacter strain Py2 and Nocardia corallina B276; Allen JR et al.; Epoxide carboxylase from the bacterium Xanthobacter strain Py2 is a multicomponent enzyme system which catalyzes the pyridine nucleotide-dependent carboxylation of aliphatic epoxides to beta-ketoacids as illustrated by the reaction epoxypropane + CO2 + NADPH + NAD+ --> acetoacetate + H+ + NADP+ + NADH . The combination of four distinct proteins, designated components I-IV, are required for the reconstitution of epoxide carboxylase activity with racemic mixtures of short-chain (C3-C5) terminal epoxyalkanes . In this work, components III and IV of the epoxide carboxylase system are shown to confer specificity for epoxyalkane enantiomers . Components I-III supported the carboxylation of (R)-epoxypropane, while components I, II, and IV supported the carboxylation of (S)-epoxypropane . At fixed concentrations of components I and II, the rates of (R)- and (S)-epoxypropane carboxylation saturated with increasing concentrations of component III or IV to give identical maximal rates for the two epoxide substrates . (S)-Epoxypropane was an inactivator of (R)-epoxypropane carboxylation by components I- III, while (R)-epoxypropane was an inactivator of (S)-epoxypropane carboxylation by components I, II, and IV . These inactivating effects were fully reversed upon the addition of the correct complementing dehydrogenase component . Amino acid sequence analysis of components III and IV demonstrates that they belong to the short-chain dehydrogenase/reductase (SDR) family of enzymes . Both components contain highly conserved residues within the coenzyme binding fold and catalytic regions found in SDR enzymes . Components III and IV are proposed to catalyze the NAD+-dependent abstraction of a hydride from a chiral secondary alcohol-like intermediate bound to the active site component of the enzyme system to form the corresponding beta-ketone intermediate . A multicomponent epoxide carboxylase system was purified to homogeneity from Nocardia corallina B276, a bacterium phylogenetically unrelated to Xanthobacter Py2, and found to consist of four proteins with functions identical to those of the Xanthobacter Py2 system . The stereoselective dehydrogenases of the Xanthobacter epoxide carboxylase system were able to substitute for the corresponding components of the N . corallina system when using (R)- and (S)-epoxypropane as substrates, and vice versa . These results provide the first demonstration of the involvement of stereospecific dehydrogenases in aliphatic epoxide metabolism and provide new insights into microbial strategies for the utilization of chiral organic molecules. Curr Opin Biotechnol, 1998 Dec, 9(6), 618 - 23 Implications of sequencing bacterial genomes for pathogenesis and vaccine development; Saunders NJ et al.; Improvements in homology search methodology and functional predictions are being complemented by the increase in the volume of sequence data with which comparative analyses can be performed . The experimental methods needed for investigation of gene function and expression in a variety of model systems of infection continue to develop . The identification of surface-exposed microbial structures and their conservation in natural populations of pathogenic species offers prospects for developing novel vaccines . A major challenge is the development of efficient screening methods to select the most promising candidates, such as immunisation with DNA. Science, 1999 Jan 15, 283(5400), 404 - 6 Diminishing returns from mutation supply rate in asexual populations; Arjan JA et al.; Mutator genotypes with increased mutation rates may be especially important in microbial evolution if genetic adaptation is generally limited by the supply of mutations . In experimental populations of the bacterium Escherichia coli, the rate of evolutionary adaptation was proportional to the mutation supply rate only in particular circumstances of small or initially well-adapted populations . These experiments also demonstrate a "speed limit" on adaptive evolution in asexual populations, one that is independent of the mutation supply rate. J Immunol, 1999 Jan 1, 162(1), 366 - 71 CD1-restricted microbial lipid antigen-specific recognition found in the CD8+ alpha beta T cell pool; Rosat JP et al.; It is generally accepted that TCR alphabeta+ CD8+ T cells recognize immunogenic peptides bound to MHC-encoded class I molecules . This recognition is a major component of the cellular response mediating immune protection and recovery from viral infections and from certain intracellular bacterial infections . Here, we report two human CD8+ TCR alphabeta+ T cell lines specific for Mycobacterium tuberculosis Ags presented in the context of CD1a or CD1c Ag-presenting molecules . These T cells recognize lipid Ags and display cytotoxicity as well as strong Th cell type I cytokine responses . By extending presentation by the CD1 system to the major TCR alphabeta+ CD8+ T cell pool, this system gains wider applicability beyond the double negative subset of T cells previously shown to have this reactivity . This implies that previous assumptions about the role of CD8+ T cells in microbial immunity may require revision as the relative proportions of CD1-restricted and MHC class I-restricted CD8+ T cells are further defined. Blood, 1999 Jan 15, 93(2), 590 - 8 Definition of dendritic cell subpopulations present in the spleen, Peyer's patches, lymph nodes, and skin of the mouse; Anjuere F et al.; Dendritic cells (DC) are highly efficient antigen-presenting cells (APC) that have an essential function in the development of immune responses against microbial pathogens and tumors . Although during the past few years our understanding of DC biology has remarkably increased, a precise characterization of the different DC subpopulations remains to be achieved with regard to their phenotype and lineage relationships . In this report, we have extensively studied the DC subpopulations present in the thymus, spleen, Peyer's patches, lymph nodes (LN) and skin of the mouse . Thymus DC and 60% spleen DC have a lymphoid DC phenotype, ie, CD8(+) DEC-205(high) Mac-1(low), whereas 40% spleen DC have a myeloid DC phenotype, ie, CD8(-) DEC-205(low) Mac-1(high) . Both CD8(+) and CD8(-) DC are leukocyte function-associated antigen-1 (LFA-1)high and highly adherent . Within Peyer's patches the majority of DC correspond to the CD8(+) DEC-205(high) Mac-1(low) lymphoid category . In the LN, together with CD8(+) and CD8(-) DC, an additional nonadherent CD8(int) LFA-1(int) subpopulation with lymphoid DC characteristics is described . Finally, in the skin both epidermal Langerhans cells (LC) and dermal DC are CD8(-)DEC-205(high) Mac-1 (high), and do not express LFA-1 . Interestingly, LC migration experiments indicate that LC underwent the upregulation of CD8 and LFA-1 upon migration to the LN, supporting the hypothesis that LC belong to the CD8(+) lymphoid lineage. Diagn Microbiol Infect Dis, 1998 Nov, 32(3), 165 - 76 Comparative study of five different techniques for epidemiological typing of Escherichia coli O157; Grif K et al.; A set of 47 Austrian human, food, and veterinary Escherichia coli O157:H7 isolates was used to evaluate five different epid