Bacteroides

Infect Immun, 1991 Aug, 59(8), 2653 - 7
Pathogen-related spirochetes identified within gingival tissue from patients with acute necrotizing ulcerative gingivitis; Riviere GR et al.; The purpose of this investigation was to determine whether monoclonal antibodies against pathogen-restricted antigens of Treponema pallidum subsp . pallidum could be used as probes for spirochetes in diseased gingival tissue from subjects with acute necrotizing ulcerative gingivitis . A biotin-streptavidin system was used to identify spirochetes bound by monoclonal antibodies in cryostat sections of tissue . Twelve of 16 tissue samples from diseased sites, but none of 8 tissue specimens from healthy sites, reacted with pathogen-restricted antibodies . Organisms were found in intact epithelium and connective tissues adjacent to ulcers . Staining intensity was often high in perivascular locations and around vesicular spaces . Monoclonal antibodies to Bacteroides gingivalis and Treponema denticola were each reactive with diseased gingival tissues, but staining was usually restricted to ulcerated areas . These studies extend recent observations that showed that subjects with acute necrotizing ulcerative gingivitis had both pathogen-related spirochetes in dental plaque and serum immunoglobulin G to pathogen-restricted antigens on T . pallidum subspecies, suggesting that pathogen-related spirochetes may be associated with the pathogenesis of certain periodontal diseases.

Glycoconj J, 1991 Aug, 8(4), 376 - 80
Single mid-chain GlcNAc beta 1-6Gal beta 1-4R sequences of linear oligosaccharides are resistant to endo-beta-galactosidase of Bacteroides fragilis; Renkonen O et al.; Endo-beta-galactosidase (EC 3.2.1.103) of Bacteroides fragilis, at 250 mU ml-1, did not cleave the internal galactosidic linkage of the linear radiolabelled trisaccharide GlcNAc beta 1-6Gal beta 1-4GlcNAc, or those of tetrasaccharides Gal beta 1-4GlcNAc beta 1-6Gal beta 1-4GlcNAc and Gal beta 1-4GlcNAc beta 1-6Gal beta 1-4Glc . The isomeric glycans which contained the GlcNAc beta 1-3Gal beta 1-4GlcNAc/Glc sequence were readily cleaved.

Oral Microbiol Immunol, 1991 Aug, 6(4), 241 - 5
Adherence to experimental pellicle of rough-type lipopolysaccharides from subgingival plaque bacteria; Okuda K et al.; The adherence of lipopolysaccharides (LPSs) from periodontal disease-associated bacteria to saliva-coated hydroxyapatite (S-HA) and serum-coated HA beads was examined by chromogenic Limulus activity (toxicolor test) . Phenol-water extracted LPS preparations from Bacteroides intermedius, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and rough-type LPS from Escherichia coli adhered to S-HA and serum-coated beads and agglutinated human erythrocytes . The adhered LPSs to S-HA and serum-coated HA beads were not removed by vigorous washing with distilled water . LPSs from Bacteroides (Porphyromonas) gingivalis strains and wild-type E . coli did not adhere to S-HA, serum-coated HA beads or show hemagglutinating activity . SDS-PAGE patterns stained with silver stain showed that LPSs adhered to S-HA, and serum-coated HA beads and erythrocytes possessed a distinct fast-migrating band similar to rough-type LPS . B . gingivalis LPSs possessed slow-migrating and repeating ladder bands similar to wild-type LPS.

Pharmazie, 1991 Aug, 46(8), 595 - 6
Influence of anticoagulants on growth and vitamin K production of intestinal bacteria; Johanni M et al.; The influence of anticoagulants on growth and vitamin K production of intestinal bacteria was studied . Bacteroides vulgatus and Escherichia coli were grown in vitro in the presence of increasing amounts of warfarin, phenprocoumon and acenocoumarol . It was found that growth of B . vulgatus was inhibited under anaerobic conditions whereas growth of E . coli under aerobic conditions was not inhibited . A specific inhibition of vitamin K biosynthesis was not observed in either case . It is concluded that therapeutic doses of anticoagulants are unlikely to affect growth or vitamin K production of intestinal bacteria.

Appl Environ Microbiol, 1991 Aug, 57(8), 2114 - 20
Conjugal transfer of a shuttle vector from the human colonic anaerobe Bacteroides uniformis to the ruminal anaerobe Prevotella (Bacteroides) ruminicola B(1)4; Shoemaker NB et al.; Prevotella ruminicola (formerly Bacteroides ruminicola) is an anaerobic, gram-negative, polysaccharide-degrading bacterium which is found in the rumina of cattle . Since P . ruminicola is thought to make an important contribution to digestion of plant material in rumina, the ability to alter this strain genetically might help improve the efficiency of rumen fermentation . However, previously there has been no way to introduce foreign DNA into P . ruminicola strains . In this study we transferred a shuttle vector, pRDB5, from the colonic species Bacteroides uniformis to P . ruminicola B(1)4 . The transfer frequency was 10(-6) to 10(-7) per recipient . pRDB5 contains sequences from pBR328, a cryptic colonic Bacteroides plasmid pB8-51, and a colonic Bacteroides tetracycline resistance (Tcr) gene . pRDB5 was mobilized out of B . uniformis by a self-transmissible Bacteroides chromosomal element designated Tcr Emr 12256 . pRDB5 replicated in Escherichia coli as well as in Bacteroides spp . and was also mobilized from E . coli to B . uniformis by using IncP plasmid R751 . However, direct transfer from E . coli to P . ruminicola B(1)4 was not detected . Thus, to introduce cloned DNA into P . ruminicola B(1)4, it was necessary first to mobilize the plasmid from E . coli to B . uniformis and then to mobilize the plasmid from B . uniformis to P . ruminicola B(1)4.

J Clin Microbiol, 1991 Aug, 29(8), 1645 - 51
Fluorescence immunoassay for detecting periodontal bacterial pathogens in plaque; Wolff LF et al.; A particle concentration fluorescence immunoassay has been modified into a bacterial concentration fluorescence immunoassay (BCFIA) to rapidly detect periodontopathic bacteria in human plaque samples . The BCFIA utilizes fluorescently tagged monoclonal antibodies (MAbs) directed against the lipopolysaccharide of selected gram-negative plaque bacteria . Microorganisms closely associated with periodontal disease that can be identified in plaque with the BCFIA include Porphyromonas gingivalis, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, and Eikenella corrodens . Briefly, the procedure involved mixing a patient's plaque sample or other bacterial preparation with a species-specific fluorescein isothiocyanate-labeled MAb in a specialized microtiter plate . This mixture was incubated to allow binding of the MAb to its homologous bacteria . The bound and unbound fluorescent tagged MAbs were separated by filtration in the modified microtiter plate, and the total bacterial bound fluorescence was determined with a fluorimeter . The number of a specific bacterial species in a given plaque sample or other bacterial suspension was estimated by reference to a primary standard carried through the BCFIA . The lower detection limit of the BCFIA was 10(3) to 10(4) bacterial cells from single cultures of bacteria or 10(4) bacterial cells in mixed cultures . The coefficient of variation within and between plates for each of the five bacterium-specific MAbs in screening plaque for the periodontal pathogens was less than 10% . These results demonstrate that microbes in plaque can be used as the solid phase in the BCFIA to detect and quantitate MAbs associated with specific bacteria quickly and reliably.

J Formos Med Assoc, 1991 Aug, 90(8), 796 - 9
In vitro activities of 36 antimicrobial agents against clinically isolated Bacteroides fragilis; Teng LJ et al.; Thirty-six antimicrobial agents were evaluated for in vitro activities against 100 clinical isolates of Bacteroides fragilis . The minimal inhibitory concentration (MIC) of each agent for each isolate was determined by the agar dilution method . Among 25 beta-lactam antibiotics, the most active agent was imipenem with an MIC90 and a geometric mean of 1 and 0.15 micrograms/ml, respectively; followed by ticarcillin-clavulanic acid, and amoxicillin-clavulanic acid . Ampicillin-sulbactam, piperacillin-tazobactam, moxalactam, and flomoxef were the next most active agents . Piperacillin, ticarcillin, ceftizoxime, cefotaxime, cefuzonam, cefoxitin, and cefmetazole were equally active with the MIC50s ranging from 4 to 16 micrograms/ml, and MIC90s ranging from 32 to greater than or equal to 256 micrograms/ml . The remaining 10 beta-lactam antibiotics, ampicillin, amoxicillin, cefazolin, cefuroxime, cefoperazone, cefmenoxime, ceftazidime, cefpirome, aztreonam, and carumonam were less active . All isolates were resistant to cefotiam at a low breakpoint . Among 6 quinolones, ciprofloxacin was the most active agent with an MIC50 and an MIC90 of 4 and 16 micrograms/ml, respectively . All isolates were resistant to nalidixic acid, pipemidic acid, cinoxacin, enoxacin, and norfloxacin . Among 5 frequently used agents, chloramphenicol, ornidazole, and metronidazole were the most effective agents which inhibited 100% of the isolates at 8, 2, and 2 micrograms/ml, respectively; while clindamycin and minocycline had less activity.

J Bacteriol, 1991 Aug, 173(16), 5239 - 43
A site-specific DNA inversion in Bacteroides plasmid pBF4 is influenced by the presence of the conjugal tetracycline resistance element; Matthews BG et al.; pBF4 is a 42-kb R plasmid from Bacteroides fragilis which transfers clindamycin resistance (Clr) independently of the chromosomal tetracycline resistance (Tcr) transfer element . We have found that this plasmid exists in two nonequimolar conformations, A and B . These forms differ by an inversion of approximately 11.5 kb which does not involve the repeated DNA sequences previously mapped on the plasmid . The presence of chromosomal tetracycline resistance conjugal elements influences the relative amounts of the two conformations: induction with tetracycline shifts the dominant form from B to A.

Biochem Biophys Res Commun, 1991 Jul 15, 178(1), 336 - 42
Characterization of Porphyromonas (bacteroides) gingivalis hemagglutinin as a protease; Nishikata M et al.; A hemagglutinin (HA) was purified to homogeneity from the membrane fraction of the oral bacterium Porphyromonas gingivalis . The HA possessed protease activity hydrolyzing proteins and arginine-containing synthetic substrates . The protease activity was inhibited by thiol-blocking reagents, and hence the HA can be characterized as a cystein protease . The HA functions as an attachment factor and its substrate-binding site is responsible for the attachment to an erythrocyte.

J Med Microbiol, 1991 Jul, 35(1), 18 - 22
Early events after intra-abdominal infection with Bacteroides fragilis and Escherichia coli; Verweij WR et al.; Growth of Bacteroides fragilis and Escherichia coli was monitored during early stages of single (mono-) and mixed intra-abdominal infection in a rat fibrin clot model . When B . fragilis and E . coli were together involved in the infection, B . fragilis numbers increased about 6 h after an initial decline . This increase was not found with B . fragilis mono-infections . The numbers of E . coli increased rapidly in both mono- and mixed infections and stayed high for several days, but only mixed infection resulted in abscesses that persisted for more than 7 days . Macrophages, the main component of the peritoneal cellular defence mechanism, were outnumbered by polymorphonuclear leucocytes during the first 6 h of infection . Further characterisation of the macrophage population by means of monoclonal antibodies showed a shift from resident to exudate macrophages as the result of influx of the latter.

J Lab Clin Med, 1991 Jul, 118(1), 48 - 55
Effect of systemic fibrinogen depletion on intraabdominal abscess formation; McRitchie DI et al.; Deposition of fibrin within the peritoneal cavity is an integral host response to local infection . To directly assess the role of fibrin deposition in the pathogenesis of intraabdominal abscess formation, the ability to induce abscesses in fibrinogen-depleted mice was examined . We hypothesized that systemic defibrinogenation with ancrod would limit the availability of fibrinogen for deposition within the peritoneal cavity and would therefore impair intraabdominal abscess formation . A gelatin capsule containing 50% sterile feces plus Bacteroides fragilis 1 x 10(9) CFU was inserted IP into control or defibrinogenated mice . System defibrinogenation resulted in alteration of the character of abscess formation, as manifested by reduced abscess size and degree of purulence . Abscesses were significantly smaller (0.18 +/- 0.02 gm {n = 29} vs . 0.09 +/- 0.02 gm {n = 11}, p less than 0.01) and less purulent (p less than 0.001) in the ancrod-treated mice than in control animals, despite equal numbers of bacteria in the abscesses recovered from both groups . The effect of ancrod was specific for defibrinogenation, because IP repletion with fibrinogen reversed the ancrod effect on abscess size . In addition to its local effects, systemic fibrinogen depletion resulted in a significant elevation in mortality following IP infection (1 of 30 control animals vs . 10 of 23 ancrod-treated animals, p less than 0.01) . However, this was not due to an increase in the magnitude of the B . fragilis bacteremia . These studies demonstrate that fibrin deposition contributes to the pathogenesis of purulent abscess formation and that systemic depletion of fibrinogen may alter host susceptibility to the consequences of infection.

J Dent Res, 1991 Jul, 70(7), 1052 - 6
Detection of two anaerobic periodontopathogens in children by means of the BANA and ELISA assays; Watson MR et al.; The mouths of young children become colonized by a variety of bacteria, but there have been only a few studies that have sought the presence of periodontopathic species in this population . Almost all of these studies used culturing techniques rather than the newer detection methodologies for various periodontopathogens . Studies in adults have shown that Treponema denticola and Porphyromonas (Bacteroides) gingivalis can be detected in dental plaque by use of the BANA and ELISA diagnostic tests . In the present study, plaque samples from four subgingival sites in each of 157 children (aged from two to 18 years) were tested for BANA hydrolysis with a BANA reagent card, and for T . denticola and P . gingivalis with an ELISA assay . Anaerobic periodontopathogens hydrolyzing the BANA substrate were found to be present in at least one of four plaque samples in 88 children (56%) . T . denticola and/or P . gingivalis were detected by ELISA in at least one plaque sample in each of 135 children (86%) . This study shows that children are widely colonized by these micro-organisms . A higher proportion of Black children than Caucasian children was colonized by these BANA-positive organisms . Also, children having a parent with a documented history of periodontal disease were more likely to be BANA-positive than were children of parents with unknown periodontal status.

J Bacteriol, 1991 Jul, 173(14), 4540 - 3
Use of an Escherichia coli beta-glucuronidase gene as a reporter gene for investigation of Bacteroides promoters; Feldhaus MJ et al.; We have constructed transcriptional fusion vectors for use in Bacteroides spp., a genus of gram-negative obligate anaerobes found in high numbers in the human colon . The reporter group in these vectors is a promoterless beta-glucuronidase gene from Escherichia coli (uidA) . Two of the vectors (pMJF-2 and pMJF-3) replicate in Bacteroides spp . The third, pCQW-1, does not replicate in Bacteroides spp . and can be used to introduce E . coli beta-glucuroindase fusions into the Bacteroides chromosome.

Infect Immun, 1991 Jul, 59(7), 2427 - 33
Human immunoglobulin G antibody response to iron-repressible and other membrane proteins of Porphyromonas (Bacteroides) gingivalis; Chen CK et al.; The human immunoglobulin G (IgG) immune response against Porphyromonas (Bacteroides) gingivalis A7A1-28 iron-repressible membrane proteins (IRMPs) and other membrane proteins was examined by immunoblot analysis . Thirty sera from patients with adult periodontitis and 30 sera from periodontally healthy subjects were included . Iron limitation of P . gingivalis was achieved by growing bacteria in brain heart infusion broth supplemented with protoporphyrin IX and 250 microM alpha, alpha'-dypyridyl, a ferrous iron chelator . Iron-sufficient growth was achieved by growing bacteria in the same medium without alpha, alpha'-dypyridyl . Human sera, in particular those from patients with periodontitis who exhibited high levels of IgG against whole cells of P . gingivalis A7A1-28 in serum in an enzyme-linked immunosorbent assay (ELISA), commonly reacted with five membrane proteins with apparent molecular masses of 80, 67.5, 51, 40.5, and 28 kDa and four IRMPs of 46, 43, 37.5, and 22 kDa . More than 80% of the sera from patients with periodontitis and high levels of IgG against strain A7A1-28 in serum by ELISA reacted with the 46-, 43-, and 37.5-kDa IRMPs, and 40% of these subjects expressed immunoreactivity against the 22-kDa IRMP . Sera from patients with periodontitis and low levels of IgG against strain A7A1-28 in serum by ELISA and sera from periodontally healthy subjects exhibited less immunoreactivity against IRMPs and the five membrane proteins of P . gingivalis . The present study indicates that P . gingivalis IRMPs are immunogenic and that these proteins are expressed in vivo.

Indian J Med Res, 1991 Jul, 93, 236 - 9
Isolation of anaerobes from clinical chancroid associated with fluctuant bubo in men; Kumar B et al.; Microbial flora especially anaerobes were studied in 67 patients with genital ulcers due to chancroid (diagnosed clinically) and 53 controls with genital ulcers due to other causes . The aerobic flora was similar in patients of chancroid with or without associated bubo and in controls . Anaerobes were however, isolated with higher frequency from chancroid ulcers associated with fluctuant bubo compared to those without bubo (P less than 0.01) and with non-fluctuant bubo (P less than 0.05) . Anaerobic bacteria like Bacteroides melaninogenicus, B . fragilis and anaerobic cocci may play a role in the perpetuation of genital ulcers and development of bubo in chancroidPIP: The microbial isolates in 67 men with genital ulcers due to chancroid and 53 controls with genital ulcers due to other causes were investigated . The study subjects comprised 14% of men presenting to a sexually transmitted disease facility in India in 1986 . Bubo was present in 37 of the chancroid patients and was fluctuant in 20 . At least 1 organism was isolated in both subjects and controls . Monomicrobial growth was observed in 20 chancroid patients and 20 controls; the remainder were polymicrobial . Anaerobic cocci were isolated in 44 (66%) of men with chancroid and 25 (47%) of those with ulcers of miscellaneous etiology, while aerobes were present in 52 (77%) men with chancroid and 39 (73%) controls . Finally, anaerobes were isolated in 17 (57%) of ulcers without bubo, 11 (65%) of ulcers with nonfluctuant bubo, and 18 (90%) of chancroid ulcers associated with fluctuant bubo . There was a significant difference in the anaerobe isolation rate in men with fluctuant bubo and those without bubo (pp0.01) and between patients with fluctuant non nonfluctuant bubo (p0.05) . The finding that anaerobes were isolated more frequently, but not at a statistically significant level, from chancroid ulcers than ulcers of other etiology fails to support the hypothesis that anaerobes are a major cause of chancroid . On the other hand, the data do support the view that anaerobes such as anaerobic cocci and Bacteroides melaninogenicus are significant in the perpetuation of chancroid ulcers and the development of fluctuant bubo .

Indian J Med Res, 1991 Jul, 93, 232 - 5
Virulence factors in Bacteroides fragilis group; Jotwani R et al.; Attempts were made to study the virulence factors in some strains of B . fragilis group in the rat model . Subcutaneous wound abscesses could be produced by 10(9) CFU/ml of live cells of all the five species of B . fragilis group tested . For determination of virulence factor cellular components (capsular polysaccharide and lipopolysaccharide) of B . fragilis were separated using gel filtration technique and injected in rats . Abscesses could be produced only by capsular polysaccharide fraction suggesting it to be the virulence factor . Studies with transmission electron microscope showed presence of capsular polysaccharide in B . fragilis and B . thetaiotaomicron, it was doubtful in B . distasonis and absent in B . ovatus and B . vulgatus . This suggested that virulence factors other than capsular polysaccharide may be responsible for pyogenic lesions in the noncapsulated species of B . fragilis group . The abscess could not be produced by 10(9) CFU/ml of heat killed cells of non-capsulated B . ovatus and B . vulgatus indicating that in live bacteria, a heat labile factor was responsible for the development of abscess.

Rev Infect Dis, 1991 Jul-Aug, 13(4), 633 - 6
Anaerobic bacteremia: decreasing rate over a 15-year period; Dorsher CW et al.; At the Mayo Clinic, the number of cases of anaerobic bacteremia decreased 45% between 1974 and 1988 . In addition, the percentage of blood cultures positive for anaerobes decreased significantly even though the total number of blood cultures performed increased . The number of anaerobic bacteremias per 100,000 patient-days also declined over the 15-year period . Organisms of the Bacteroides fragilis group ranked third in frequency with respect to other organisms that caused aerobic and anaerobic bacteremia in 1974 but ranked only seventh in 1988 and caused slightly less than one-half of the anaerobic bacteremias . The mechanisms responsible for these changes are unclear but might relate to earlier recognition and treatment of localized anaerobic infection, widespread preoperative use of agents prior to bowel surgery, and use of broad-spectrum antimicrobial regimens that include agents with activity against anaerobes.

J Clin Periodontol, 1991 Jul, 18(6), 406 - 10
Microbiology in the management of destructive periodontal disease; van Winkelhoff AJ et al.; This paper summarizes the rationale for the application of microbiology in the management of destructive periodontal diseases . The subgingival microbiota in patients with severe periodontitis is complex and contains high numbers of obligate anaerobic bacteria as well as facultative micro-organisms . It has become clear that major differences exist in the composition of the subgingival microflora . These differences are not only quantitative but also qualitative . Difference in plaque composition is the basis for the application of clinical microbiology in the management of periodontal disease . Several bacterial species have emerged as useful indicators for progressive periodontitis . In this respect, the importance of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Bacteroides intermedius has been shown in a number of studies . It has become clear that A . actinomycetemcomitans is not specifically associated with the local form of juvenile periodontitis, but this micro-organism is probably also of importance in severe periodontitis in adult patients . Selection of individuals with an A . actinomycetemcomitans associated periodontitis is essential since successful treatment in these patients needs an adjunctive antibiotic therapy . Microbiological testing can be useful in patients showing a poor response to periodontal treatment (refractory periodontitis) . Factors which may be responsible include poor oral hygiene, poor subgingival debridement, the patient's susceptibility and a subgingival microflora resistant to therapy . In this patient category, microbiological testing is capable of diverting continuing periodontal treatment . Furthermore, microbiology can be useful in evaluating periodontal treatment . Successful elimination of specific periodontopathic microorganisms can be used to determine recall intervals.

J Bacteriol, 1991 Jul, 173(14), 4263 - 70
Identification of Porphyromonas gingivalis components that mediate its interactions with fibronectin; Lantz MS et al.; Porphyromonas (Bacteroides) gingivalis W12 binds and degrades human plasma fibronectin . In the presence of the protease inhibitor N-alpha-p-tosyl-L-lysyl chloromethyl ketone, P . gingivalis cells accumulated substantial amounts of 125I-fibronectin as a function of incubation time . Fibronectin binding was specific, reversible, and saturable . The Kd for the reaction was estimated to be on the order of 100 nM, and there was an average of 3.5 x 10(3) fibronectin binding sites per cell . Unlabeled fibronectin inhibited the binding of 125I-fibronectin to bacteria; however, fibrinogen was an even more efficient inhibitor of 125I-fibronectin binding . Unrelated proteins were without effect on fibronectin binding . A fibronectin-binding component (Mr, 150,000) was identified in sodium dodecyl sulfate-solubilized P . gingivalis . Fibronectin was degraded into discrete peptides by P . gingivalis W12 . The degradation of fibronectin was inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone . Two P . gingivalis components (Mrs, 120,000 and 150,000) degraded fibronectin in substrate-containing gels following sodium dodecyl sulfate-polyacrylamide gel electrophoresis . In a previous study (M . S . Lantz, R . D . Allen, T . A . Vail, L . M . Switalski, and M . Hook, J . Bacteriol . 173:495-504, 1991), we found that the same strain of P . gingivalis bound and subsequently degraded human fibrinogen via apparently distinct cell surface components of molecular sizes similar to those of components now implicated in the binding and degradation of fibronectin . These results raise the possibility that the two ligands are recognized and modified by the same components on P . gingivalis W12 . In support of this hypothesis, unlabeled fibrinogen effectively inhibited the binding of 125I-fibronectin to bacteria and blocked 125I-fibronectin binding to a P . gingivalis ligand-binding component (Mr, 150,000 immobilized on a nitrocellulose membrane.

J Antimicrob Chemother, 1991 Jul, 28(1), 55 - 60
Comparative susceptibility of cefminox and cefoxitin to beta-lactamases of Bacteroides spp; Soriano F et al.; The susceptibility of the new cephamycin antibiotic, cefminox, to hydrolysis by various types of beta-lactamase produced by organisms of the Bacteroides fragilis group was compared with that of cefoxitin . Several enzymes were able to achieve complete hydrolysis of both drugs during overnight incubation, but no marked difference between the rates of inactivation of cefminox and cefoxitin was observed . Susceptibility of the cephamycins to crude extracts of beta-lactamases from the test strains of Bacteroides spp . did not correlate with the results of conventional minimum inhibitory concentration titrations . Possible reasons for these discrepancies are discussed.

J Antimicrob Chemother, 1991 Jul, 28(1), 47 - 53
Lactate dehydrogenase activity as a cause of metronidazole resistance in Bacteroides fragilis NCTC 11295; Narikawa S et al.; Enzymes acting on pyruvate as a parameter of the ATP regeneration system were studied as a cause of metronidazole resistance in Bacteroides fragilis NCTC 11295 . The resistant strain had higher lactate dehydrogenase activity and produced more lactate than susceptible strains, suggesting that the enzyme is more active in lactic acid fermentation . Furthermore, the reaction catalysed by lactate dehydrogenase occurred up to 48 mg/L metronidazole, whereas the reaction catalysed by pyruvate: ferredoxin oxidoreductase reaction stopped at 2 mg/L . The mechanism of metronidazole resistance in B . fragilis NCTC 11295 may be due to the high activity of lactate dehydrogenase which compensates for the decreased activity of pyruvate: ferredoxin oxidoreductase in the presence of metronidazole.

J Dent Hyg, 1991 Jul-Aug, 65(6), 289 - 95
The effects of subgingival irrigation with chlorhexidine and stannous fluoride . A preliminary investigation; Krust KS et al.; This pilot study compared the effectiveness of subgingival irrigation with 0.12% chlorhexidine, 1.64% stannous fluoride, and sterile saline, in addition to scaling and root planing, on levels of Bacteroides porphyromonas and the clinical parameters bleeding tendency, probing depth, and attachment level . A convenience sample of eight patients, exhibiting 32 sites with moderate periodontal disease, was randomly assigned to receive all treatments according to a four-quadrant treatment design . Subgingival irrigation was performed at 0, 1, 2, and 3 weeks following scaling and root planing . Clinical and microbial assessments were measured at baseline, 4, 8, and 12 weeks . Data were analyzed using a two-factor repeated measure analysis of variance, and the Newman-Keuls sequential range test or Friedman test and Kruskal-Wallis test revealed statistically significant (p less than .01) improvements in probing depths, attachment levels, and Bacteroides porphyromonas for all groups at 12 weeks when compared to baseline values . No statistically significant differences occurred between any of the treatment groups at any time period . Based on the findings of this investigation, it has been concluded that four weekly irrigations with 0.12% chlorhexidine, 1.64% stannous fluoride, or saline irrigation did not enhance the beneficial effects of scaling and root planing alone.

J Chromatogr, 1991 Jun 21, 546(1-2), 273 - 87
Ion chromatographic methods for the detection of starch hydrolysis products in ruminal digesta; Barsuhn K et al.; Dionex high-performance ion chromatographic methods were evaluated for separation and quantitation of plant sugars and starch digestion products in the ruminal digesta of cattle . Mono- and disaccharides were eluted from a Dionex CarboPac PA1 column with sodium hydroxide used isocratically or as a pH gradient . Maltooligosaccharides which had a degree of polymerization (DP) less than 30 glucose residues were eluted in 60 min by a sodium hydroxide eluent containing a sodium acetate gradient . Carbohydrates were detected amperometrically . Responses were linear (r2 greater than 0.99) for glucose, disaccharides and maltooligosaccharides (DP less than 8) . Precipitation and solid-phase extraction methods were evaluated for clean-up of samples of feedstuffs, ruminal contents, and bacterial culture fluids . Perchloric acid precipitation hydrolyzed sucrose but did not affect recoveries of cellobiose, isomaltose or maltose . Ethanol in concentrations of 79 and 86% precipitated maltooligosaccharides having chain lengths larger than 14 and 9 glucose residues, respectively . Maltooligosaccharide recoveries from solid-phase extraction columns varied with maltooligosaccharide size and column packing . Recoveries were greater than 94% for short chains (DP less than 6) eluted from phenyl-substituted columns and variable for all oligosaccharides eluted from C18 columns . Applications of these methods are presented and include: (1) detection of sugars in ruminant feed, (2) monitoring changes in ruminal sugars after feeding and (3) monitoring changes in extracellular sugars and oligosaccharides in the culture fluids of the ruminal bacterium, Bacteroides ruminicola.

Postgrad Med, 1991 Jun, 89(8), 221 - 4, 227-30, 233-4
Anaerobic infections . The basics for primary care physicians; Feleke G et al.; Anaerobic bacteria constitute a major portion of the normal human microflora, and some of them can cause disease in contiguous body parts, especially if there is a mucosal break . Most anaerobic infections are polymicrobial . Because anaerobes are difficult to culture, diagnosis is often made on the basis of clinical clues . Thus, knowledge of the common sites, predisposing conditions, and other representative features of anaerobic infections is critical . For anaerobic infections above the diaphragm, where Bacteroides fragilis is not a common isolate, high-dose penicillin G therapy is usually sufficient . Addition of clindamycin (Cleocin) or metronidazole (Flagyl, Metryl, Protostat) may be necessary for serious infections . Cefoxitin sodium (Mefoxin) or clindamycin is adequate for most anaerobic infections occurring outside the central nervous system . Metronidazole, chloramphenicol, imipenem, or beta-lactam antibiotics combined with beta-lactamase inhibitors may be preferable for serious infections . Appropriate coverage for aerobic bacteria must be included in the treatment regimen . Drainage of abscesses, decompression of infected spaces, debridement of necrotic tissue, and removal of foreign bodies are critical in management of many anaerobic infections.

Infect Immun, 1991 Jun, 59(6), 2075 - 82
Immunochemical characterization of two surface polysaccharides of Bacteroides fragilis; Pantosti A et al.; Immunochemical analysis of the capsular polysaccharide from Bacteroides fragilis NCTC 9343 revealed a novel structure composed of two distinct polysaccharides . Immunoelectrophoresis of an extract of purified surface polysaccharide from fermenter-grown organisms showed a complex precipitin profile with varying anodal mobility . DEAE-Sephacel anion-exchange chromatography of the polysaccharide extract failed to separate the majority of this aggregate . Disaggregation of this complex was accomplished by very mild acid treatment; purification was achieved by DEAE-Sephacel anion-exchange chromatography . Polysaccharide A had a neutral charge at pH 7.3, a net negative charge at pH 8.6, and an average Mr = 110,000; chemical analysis showed it to contain galactose, galactosamine, and an unidentified amino sugar . Polysaccharide B eluted from the anion-exchange column with increased salt concentration; it had a net negative charge and an average Mr = 200,000, and contained fucose, galactose, quinovosamine, galacturonic acid, and glucosamine . Neither of these polysaccharides contained detectable 3-deoxy-D-manno-octolusonic acid, and both were recognized as distinct antigens on the basis of their reactivity with monoclonal antibodies CE3 and F10, which reacted with the complex before acid treatment . These data indicate that the capsule of B . fragilis NCTC 9343 comprises two discrete, surface-exposed polysaccharides with differing physiochemical properties that are distinct from the lipopolysaccharide of this organism . The finding of two surface polysaccharides has not been described for other bacteria pathogenic to humans.

Infect Immun, 1991 Jun, 59(6), 1927 - 31
Immune modulation of Prevotella intermedia colonization in squirrel monkeys; Clark WB et al.; Colonization of the gingival crevice by black-pigmented Porphyromonas or Prevotella spp . (BP/P), including Porphyromonas gingivalis (formerly Bacteroides gingivalis) and Prevotella intermedia (formerly Bacteroides intermedius), is thought to be an important ecological event which may result in the destruction of connective tissues supporting the teeth . Theoretically, periodontal diseases could be prevented if these or other periodontal pathogenic microorganisms did not colonize the subgingival area . The humoral immune response is one mechanism which may modulate bacterial colonization in the gingival crevice . In the present study, we tested the effect of systemic humoral immunity on subgingival colonization by indigenous P . intermedia in squirrel monkeys (Saimiri sciureus) . Animals rendered essentially free of detectable BP/P by a single scaling, 10 days of tetracycline therapy, and toothbrushing three times per week were immunized with P . intermedia 1447 or were sham immunized with phosphate-buffered saline . Subsequently, all oral hygiene procedures were discontinued and five teeth in one quadrant were ligated with bacterium-soaked suture material to facilitate BP/P colonization . Immunization resulted in a significant increase in the level of immunoglobulin G anti-P . intermedia antibody in serum . Two weeks after ligation was initiated, P . intermedia could be detected in five of six sham-immunized and three of six immunized animals . Immunization was associated with a reduction in the emergence of indigenous P . intermedia in the gingival crevice.

J Biol Buccale, 1991 Jun, 19(2), 155 - 60
Targetting the production of monoclonal antibodies to the hemagglutinating adhesin of Bacteroides (Porphyromonas) gingivalis by injection of an immunoprecipitate from crossed immunoelectrophoresis; Deslauriers M et al.; This study has demonstrated that the production of monoclonal antibodies (MAbs) can be targetted to a predetermined antigen by immunization with the relevant immunoprecipitate (IP) excised from an agarose gel . The target antigen was the hemagglutinating adhesin HA-Ag2 of Bacteroides (Porphyromonas) gingivalis precipitated from a crude antigen extract with a rabbit antiserum in crossed immunoelectrophoresis . The immunization protocol used included: subcutaneous injection of 1 IP in Freund's complete adjuvant to Balb/c mice on day 0 and of 0.5 IP on day 8, followed by an intravenous booster injection of outer membranes on day 15, 4 days before the fusion . Of the 9 MAbs obtained, 8 were specific for HA-Ag2 since they reacted with its characteristic electrophoretic bands at 43 and 49 kDa . The ninth MAb was specific for the B . gingivalis lipopolysaccharide . The method allows for easy obtention of MAbs of predetermined specificity without purification of the antigen.

J Antimicrob Chemother, 1991 Jun, 27(6), 721 - 31
Susceptibility of Bacteroides ureolyticus to antimicrobial agents and identification of a tetracycline resistance determinant related to tetM; de Barbeyrac B et al.; The in-vitro activity of ten antimicrobial agents was evaluated for 28 clinical isolates of Bacteroides ureolyticus, an obligate anaerobe associated with non-gonococcal urethritis . The isolates were characterized by plasmid DNA profile and PAGE protein pattern . All isolates were inhibited at concentrations equal to or lower than the recommended breakpoint concentration for ampicillin (16 mg/l), metronidazole (16 mg/l) and erythromycin (4 mg/l) . Twenty-seven isolates were inhibited by less than or equal to 2 mg/l of ciprofloxacin, pefloxacin and ofloxacin . Four isolates were tetracycline-resistant requiring 2-64 mg/l of tetracycline, minocycline or doxycycline for inhibition . In two tetracycline-resistant isolates tetM was demonstrated by dot-blot and Southern hybridizations . These two isolates did not contain a plasmid and had a PAGE protein pattern type III . These data confirm the spread of the tetM determinant in various bacteria of the genital tract.

Antimicrob Agents Chemother, 1991 Jun, 35(6), 1219 - 24
Effect of beta-lactamase inhibitors on the activities of various beta-lactam agents against anaerobic bacteria; Wexler HM et al.; The in vitro activities of several new beta-lactam-beta-lactamase inhibitor combinations (piperacillin plus tazobactam, ceftizoxime and cefonicid with sulbactam and clavulanic acid, and ampicillin plus 8 micrograms of sulbactam per ml) were tested with anaerobic bacteria and compared with known beta-lactam-beta-lactamase inhibitor combinations and other potent antianaerobe agents . All the combinations tested (except for the cefonicid-inhibitor combinations) were active against almost all strains of the Bacteroides fragilis group . This report indicates that beta-lactamase inhibitors may improve the activity of beta-lactam agents with marginal activity against the B . fragilis group.

Antimicrob Agents Chemother, 1991 Jun, 35(6), 1214 - 8
Susceptibilities of 394 Bacteroides fragilis, non-B . fragilis group Bacteroides species, and Fusobacterium species to newer antimicrobial agents; Appelbaum PC et al.; The susceptibilities of 374 selected beta-lactamase-producing gram-negative anaerobes (including 22 cefoxitin-resistant strains and 36 strains refractory to the enhancing effect of beta-lactamase inhibitors) and 20 beta-lactamase-negative strains were tested by agar dilution against selected new agents . The organisms included 217 Bacteroides fragilis group strains, 137 non-B . fragilis group Bacteroides spp., and 40 fusobacteria . All strains were susceptible to piperacillin-tazobactam, imipenem, and meropenem . For the B . fragilis group, 96% were susceptible to ampicillin-sulbactam, 95% were susceptible to amoxicillin-clavulanate and cefoperazone-sulbactam, 94% were susceptible to tosufloxacin, 91% were susceptible to cefoxitin, 88% were susceptible to trospectomycin, and 73% were susceptible to cefotetan . For the beta-lactamase-positive non-B . fragilis group Bacteroides spp., greater than or equal to 94% were susceptible to cefoxitin, amoxicillin-clavulanate, ampicillin-sulbactam, cefoperazone-sulbactam, and trospectomycin, 90% were susceptible to cefotetan, and 85% were susceptible to tosufloxacin (the most resistant strains were B . bivius and B . disiens) . For the beta-lactamase-positive fusobacteria, greater than or equal to 97% were susceptible to amoxicillin-clavulanate, ampicillin-sulbactam, cefoperazone-sulbactam, trospectomycin, and cefoxitin, 90% were susceptible to cefotetan, and 89% were susceptible to tosufloxacin . All agents showed excellent activity against beta-lactamase-negative strains (for trospectomycin, 95% were susceptible; for all other drugs, 100% were susceptible) . Overall, both carbapenems and piperacillin-tazobactam were most active . Amoxicillin-clavulanate, ampicillin-sulbactam, and cefoperazone-sulbactam lacked activity against some cefoxitin-resistant B . fragilis group strains but had excellent activity against other organisms . Tosufloxacin, a new quinolone, had very good activity against B . fragilis group strains (94% susceptible), good activity against other beta-lactamase-positive strains (less than or equal 85% susceptible), and excellent activity against beta-lactamase-negative strains (100% susceptible; MIC for 90% of strains, 0.5 microgram/ml) . Trospectomycin was active against >90% of all strains except for B . fragilis group strains (88% susceptible; MIC for 90% of strains, 32 microgram/ml) . Clinical studies are required to delineate the role of newer agents in the therapy of anaerobic infections.

J Vet Pharmacol Ther, 1991 Jun, 14(2), 185 - 92
Comparative in vitro susceptibility of Bacteroides and Fusobacterium isolated from footrot in sheep to 28 antimicrobial agents; Piriz Duran S et al.; The agar dilution method was used to determine the bacteriostatic activity of 28 antimicrobial agents against 141 strains to the genus Bacteroides and 29 strains from the genus Fusobacterium . All organisms were isolated from clinical cases of ovine footrot . The strains were isolated from 125 Merino sheep, over a period of 2 years, from January 1987 to December 1988 . The three ureidopenicillins studied (azlocillin, mezlocillin and piperacillin) proved to be the most effective antimicrobial agents . Chloramphenicol, metronidazole and tinidazole effectively inhibited the growth of Bacteroides spp., while phosphomycin was active against Fusobacterium spp.

J Gen Microbiol, 1991 Jun, 137 ( Pt 6), 1445 - 52
Multivariate analyses of fatty acid data from whole-cell methanolysates of Prevotella, Bacteroides and Porphyromonas spp; Brondz I et al.; The genus Bacteroides contains a number of biochemically and physiologically heterogeneous groups of organisms and needs taxonomic revision . In this study cellular fatty acids from a number of Bacteroides spp . were identified and quantified using gas chromatography and gas chromatography-mass spectrometry . The chemical data were then subjected to principal components analysis . In B . fragilis, which is the type species of the genus Bacteroides, C3-OH-iso17 was the predominant fatty acid (38.0%) and Cante15 was present in higher amounts (32.7%) than Ciso15 (14.6%) . B . fragilis thus differed from all the other species examined: Prevotella (Bacteroides) buccae, P . (B.) oralis, P . (B.) oris, P . (B.) disiens, P . (B.) veroralis, P . (B.) heparinolytica and Porphyromonas (Bacteroides) endodontalis . Principal components analysis also enabled the closely related P . buccae, P . oralis and P . oris to be differentiated.

J Gen Microbiol, 1991 Jun, 137 ( Pt 6), 1431 - 5
A study of the candidate virulence factors of Bacteroides fragilis; Namavar F et al.; Bacteroides fragilis strains were classified as virulent or avirulent on the basis of their clearance from the subcutaneous tissues of mice . To determine the factors which may contribute to the virulence of B . fragilis strains, we studied encapsulation, hydrophobicity, growth rate, serum sensitivity, agglutination with erythrocytes of different origin, and neuraminidase production . The strains of the virulent group displayed a higher growth rate in broth and a lower sensitivity to the bactericidal activity of serum than the strains of the avirulent group . They also agglutinated different types of erythrocytes more strongly than did the avirulent strains . No significant differences were found between the two groups of strains as regards encapsulation, hydrophobicity and neuraminidase activity.

Br J Oral Maxillofac Surg, 1991 Jun, 29(3), 180 - 2
British oral and maxillofacial surgeons' views on the aetiology and management of acute pericoronitis; Gill Y et al.; Acute pericoronitis is a common oral infection characterised by a predominance of anaerobic micro-organisms such as peptococci, peptostreptococci, bacteroides and fusobacteria, and also spirochaetes . Penicillins such as amoxycillin, and metronidazole are effective antimicrobials in the treatment of acute pericoronitis . This study presents the views of a group of British Oral and Maxillofacial Surgeons as to the causative microbial agents and the antimicrobial management of acute pericoronitis.

J Periodontol, 1991 Jun, 62(6), 377 - 86
Incidence of periodontitis recurrence in treated patients with and without cultivable Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis: a prospective study; Listgarten MA et al.; A total of 98 adults previously treated for moderate to advanced periodontitis and on a trimonthly recall schedule were screened for the presence of critical levels of Actinobacillus actinomycetemcomitans, Prevotella (Bacteroides) intermedia, and Porphyromonas (Bacteroides) gingivalis . Patients with at least 2 positive sites were placed in a positive group and patients without or with low levels of these bacteria in a negative group . During the 30-month study the incidence of disease recurrence was greater in the positive group, but did not reach statistical significance . Positive patients with deeper pockets tended to be at greater risk of developing recurrent disease than those with shallower pockets . In the positive group only, both A . actinomycetemcomitans recovery and antibody levels to A . actinomycetemcomitans strain NCTC 9710 (serotype c) were inversely correlated with disease recurrence . The presence of A . actinomycetemcomitans and P . intermedia above critical levels did not reliably predict future episodes of disease recurrence in this population . The sparse recovery of P . gingivalis did not permit us to assess its diagnostic value . With the exception of P . gingivalis, for which insufficient data were available, the results indicate that the presence or absence of the above bacterial species cannot of itself serve as a reliable predictor of future episodes of recurrent disease in a population of treated patients on a regular trimonthly recall schedule.

Infect Immun, 1991 Jun, 59(6), 1972 - 7
Bacteroides (Porphyromonas) gingivalis fimbriae activate mouse peritoneal macrophages and induce gene expression and production of interleukin-1; Hanazawa S et al.; The purpose of this study was to examine whether Bacteroides (Porphyromonas) gingivalis fimbriae, an important structure involved in attachment of the bacteria to periodontal tissues, activate macrophages and subsequently induce gene expression and production of interleukin-1 (IL-1) in the cells . The fimbriae increased glucose consumption and lysozyme activity in BALB/c macrophages, both criteria of macrophage activation of peritoneal macrophages, in a dose-dependent fashion . A marked increase in the mRNA level of the c-myc gene, an oncogene, in the cells was observed after a 1-h treatment with the fimbriae, and the level decreased rapidly after 3 h . The fimbriae (4 micrograms of protein per ml) markedly induced IL-1 alpha and IL-1 beta gene expression in the cells and IL-1 production . The expression of IL-1 alpha and IL-1 beta genes measured in terms of specific mRNA increased 1 h after the start of treatment and peaked at 6 h . Such increased expression of IL-1 beta was also observed in C3H/HeJ mice, a lipopolysaccharide low-responder strain . The fimbriae stimulated transcriptional activity of IL-1 beta in the cells, but not that of IL-1 alpha . We also observed that fimbriae-induced IL-1 gene expression was not regulated by endogenous prostaglandin triggered by the fimbriae . Therefore, these observations suggest that B . gingivalis fimbriae may be involved in the pathogenesis of adult periodontal disease via triggering of IL-1 production by monocytes/macrophages in periodontal diseases.

Afr J Med Med Sci, 1991 Jun, 20(2), 115 - 21
Rapid presumptive identification of human black pigmented Bacteroides species; Eke PI et al.; A simple and reliable technique is described for the rapid presumptive identification of black pigmented Bacteroides species of human origin . This method involved a microtitration technique that detected the hydrolysis of specific chromogenic enzyme substrates and haemagglutination of sheep erythrocytes . Pure cultures of black pigmented Bacteroides strains, representing the eight human species, were successfully differentiated and identified within 4 h by the identification scheme developed with this method . This is a highly reproducible method and the scheme should be useful in laboratories lacking the sophisticated equipment often needed for the identification of black pigmented Bacteroides.

Appl Environ Microbiol, 1991 Jun, 57(6), 1615 - 23
A Bacteroides ovatus chromosomal locus which contains an alpha-galactosidase gene may be important for colonization of the gastrointestinal tract; Valentine PJ et al.; An alpha-galactosidase gene has been cloned from the human colonic Bacteroides species Bacteroides ovatus 0038 . This alpha-galactosidase appears to be distinct from two previously characterized alpha-galactosidases, I and II, from the same strain and has been designated alpha-galactosidase III . Partially purified alpha-galactosidase III from Escherichia coli EM24 containing pFG61 delta SE had a pI of 7.6, as compared with the reported pI values for the known alpha-galactosidases of 5.6 for I and 6.9 for II . Its molecular weight as estimated on sodium dodecyl sulfate-polyacrylamide gels was 78,000, whereas the molecular weights of alpha-galactosidases I and II were 85,000 and 80,500, respectively . The only substrate hydrolyzed by alpha-galactosidase III was melibiose, whereas the other two alpha-galactosidases were able to degrade melibiose, raffinose, and stachyose and partially degraded guar gum . alpha-Galactosidase III had a pH optimum of 6.7 to 7.2 . Finally, a single crossover insertion which disrupted the gene in the B . ovatus chromosome had no effect on expression of alpha-galactosidases I and II . Although this insertion had no effect on the ability of B . ovatus to grow in laboratory medium on any of the galactoside-containing carbohydrates tested, the insertion mutant was outcompeted by wild type when a combination of mutant and wild type was used to colonize germfree mice . Insertions on either side of the gene had the same effect . Thus, the locus which contains alpha-galactosidase III may be important for colonization in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

J Periodontol, 1991 Jun, 62(6), 394 - 401
Defective neutrophil function in an insulin-dependent diabetes mellitus patients . A case report; Cutler CW et al.; The objective of this study was to evaluate the polymorphonuclear leukocyte (PMN) function in a poorly controlled adult insulin-dependent diabetic patient (IDDM) with severe recurrent periodontitis, while describing the microbiological and clinical findings . Chemotaxis, superoxide production, and phagocytosis and killing of Porphyromonas (Bacteroides) gingivalis by the IDDM PMN were evaluated 1 week before treatment relative to a healthy, matched control . These analyses revealed a significant (P less than .05) depression in the number of IDDM PMNs migrating along an FMLP gradient (Boyden chamber assay) . In addition, a significant (P less than .05) enhancement of IDDM PMN superoxide production in response to opsonized zymosan (cytochrome C reduction) was observed . Phagocytosis and killing (fluorochrome phagocytosis assay) by IDDM PMN of two P . gingivalis strains was also impaired significantly (P less than .05) . The subgingival microflora contained significant levels of P . gingivalis, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and Peptostreptococcus micros . Periodontal treatment consisted of extraction of hopeless teeth, scaling and root planing and 3 weeks of Augmentin therapy . The antibiotic therapy resulted in unrecoverable numbers of the putative pathogens and a reduction in both gingival inflammation and disease progression . The IDDM healing response to previous surgical treatment and extractions was poor, presumably due to a marked thrombocytopenia (91 x 10(3) platelets/mm3).

J Med Microbiol, 1991 May, 34(5), 253 - 7
The resolution of bacteroides lipopolysaccharides by polyacrylamide gel electrophoresis; Maskell JP; The lipopolysaccharides (LPS) of the 10 species of the genus Bacteroides (sensu stricto) were extracted by the proteinase K method and their resolution compared by several methods of polyacrylamide gel electrophoresis (PAGE) . These included sodium dodecyl sulphate (SDS)-PAGE with and without urea, polyacrylamide gradient gels and Tricine {N-Tris (hydroxymethyl) methyl glycine}-SDS-PAGE . The original discontinuous system showed good resolution of LPS from B . thetaiotaomicron, B . caccae and B . ovatus and this was enhanced by urea; B . vulgatus showed a typical ladder pattern associated with repeating polysaccharide units of the O side chains . The LPS profiles of the other species, including B . fragilis, were poorly resolved; the majority of components migrated with the leading edge of the wave front . The resolution of the LPS of these species was marginally improved with gradient gels but the majority of components were separated only within the regions of high polyacrylamide concentration . The Tricine-SDS system was consistently superior to the other methods, with excellent resolution of the LPS profiles of all Bacteroides species.

Mol Microbiol, 1991 May, 5(5), 1211 - 9
Escherichia coli chromosomal mutations that permit direct cloning of the Bacteroides fragilis metallo-beta-lactamase gene, ccrA; Rasmussen BA et al.; The class B, metallo-beta-lactamase genes ccrA (carbapenem- and cephamycin resistance) from three Bacteroides fragilis isolates--QMCN3, QMCN4, and TAL3636--were cloned and expressed in Escherichia coli . Cloning of the genes, by selecting for ampicillin resistance, was facilitated by two classes of Escherichia coli chromosomal mutations which resulted in at least a 5-10-fold increase in metallo-beta-lactamase enzymatic activity . The observed increase in enzymatic activity is due to either increased translation of the ccrA gene or an effect on localization or stability of the protein . Comparison of the DNA sequences of the three ccrA genes revealed that their protein-coding sequences shared greater than 97% DNA sequence identity . However, the 5' upstream sequence for the TAL3636 ccrA gene was unrelated to that of the other two genes.

Indian J Med Res, 1991 May, 93, 171 - 3
Detection of Bacteroides infection by counter immunoelectrophoresis test; Lalitha MK et al.; The counterimmunoelectrophoresis (CIE) test using sonicated antigens of Bacteroides fragilis NCTC 2553 and a B . asaccharolyticus strain, standardised in the laboratory yielded a negative result in the 50 normal sera tested, while it was positive in 24 of 34 (71%) patients with infection due to black pigmented bacteroides and in 10 of 15 (67%) with B . fragilis infection . The microagglutination test (MAT) done in parallel showed a positivity of only 44 and 40 per cent respectively . The CIE test done with B . asaccharolyticus antigen was negative in 87 per cent of patients with infection due to B . fragilis whereas MAT showed cross reactivity to a greater extent.

J Clin Immunol, 1991 May, 11(3), 132 - 42
Rheumatoid factor (RF) distribution in periodontal disease; The J et al.; This study investigated the occurrence of an autoantibody, IgM rheumatoid factor, that may result from the chronic inflammation noted in periodontal disease and rheumatoid arthritis . In order to detect IgM-RF, a biotin-avidin ELISA was developed . This assay was found to be sensitive and accurate by testing a rheumatoid arthritis population . The characteristics of this rheumatoid arthritis group were further determined, such that the total serum immunoglobulin concentrations were slightly elevated although within the normal range for IgM, IgG, and IgA; IgG antibody levels were elevated against oral microorganisms of the genus Capnocytophaga, while elevated IgM antibody levels were noted to Bacteroides species . In a population of 260 subjects of which 171 were periodontal disease patients, 16 of 171 (9.4%) were seropositive for IgM-RF, of which the predominant disease types were advanced destructive periodontitis and adult periodontitis . For comparison, a random population of seronegative periodontal disease patients was constructed that was matched for sex and approximate age to the seropositive group . The total immunoglobulin levels of the two groups were not significantly different and the means of both were slightly lower than the rheumatoid arthritis group . When the antibody profiles of the two periodontal disease populations were compared it became evident that the RF-positive group showed IgM and IgG antibody that was significantly elevated to Capnocytophaga species and F . nucleatum . Therefore, the chronic inflammation associated with periodontitis appears to increase significantly the formation of IgM-RF; however, there does appear to be a relationship between IgM-RF and elevated antibody to selected oral microorganisms.

J Antimicrob Chemother, 1991 May, 27(5), 599 - 606
Meropenem: in-vitro activity and kinetics of activity against organisms of the Bacteroides fragilis group; Garcia-Rodriguez JA et al.; Meropenem was compared with imipenem and nine other antimicrobial agents, against 101 strains of the Bacteroides fragilis group . Meropenem was active against all strains tested, and its activity was similar to, and in many cases better than, that of imipenem . The activity of meropenem was similar to that of metronidazole, and greater than that of the other antimicrobial agents tested . The bactericidal activity of meropenem against B . fragilis was impressive, since the MBC to MIC ratios were no greater than two . The bactericidal activity was confirmed by time-killing curve assays with two strains which showed that meropenem was rapidly bactericidal and reduced the initial inoculum significantly during the first 4-6 h . The postantibiotic effect of meropenem (2-4 h) and a sub-inhibitory concentration of 1/4 x MIC suggested that meropenem interferes with the normal growth of B . fragilis, even when administered concentrations fall below the MIC . MICs of meropenem were affected minimally by the pH of the medium or by an increase in inoculum size . Meropenem continued to have good activity against a B . fragilis strain that had been induced for the production of cephalosporinase . The in-vitro data presented in this paper indicate that meropenem is a promising antimicrobial agent which may be useful in the treatment of problematic mixed infections.

Can J Microbiol, 1991 May, 37(5), 368 - 76
The stability of outer-membrane protein and antigen profiles of a strain of Bacteroides intermedius grown in continuous culture at different pH and growth rates; Bowden GH et al.; The stability of the outer-membrane proteins and antigens of a strain of Bacteroides intermedius (VPI 8944 group genotype II) grown in continuous culture at varying pH and growth rates (D = 0.025-0.2 h-1, pH 6.0-7.3) has been measured . The membranes showed nine major proteins (greater than 67-19.55 kilodaltons) and six major antigens (65-28 kilodaltons) . Membrane proteins and antigens were stable under the conditions tested; the major proteins were detected in all membranes, and the antigen profiles tested with different antisera showed maximum similarities of 82-95% . Differences did occur in the amounts of membrane proteins synthesized; cells at high growth rates and those growing on the surfaces in the chemostat showed increased amounts of two proteins (40 and 32 kilodaltons) and possibly novel proteins of 24 and 25 kilodaltons . In addition, these membranes reflected increased synthesis or a change to increased reactivity of antigens between 20.5 and 24 kilodaltons . The results indicate stability of the expression of outer-membrane proteins and antigens in environments of differing pH and under different growth rates . However, the amount of these molecules synthesized can vary, and increases in certain proteins and antigens occur as the growth rate increases and the organisms grow on surfaces.

Am J Vet Res, 1991 May, 52(5), 738 - 41
Identity of Bacteroides isolates and previously named Bacteroides spp in clinical specimens of animal origin; Jang SS et al.; During the years 1984 through 1987 2,574 isolates of obligately anaerobic bacteria were isolated from samples submitted for analysis . The most common anaerobic isolates were members of the genus Bacteroides, representing 44.6% of the isolates . Of these, the most commonly isolated identifiable microorganisms were bile-resistant and nonpigmented, belonging to the B fragilis group of Bacteroides . Importantly, obvious predilections for any one species or group of Bacteroides were not apparent for animal or site (condition), except that the proportion of isolates belonging to the nonpigmented, bile-resistant group obtained from the respiratory tract was significantly (P less than 0.005) higher than that not belonging to this group . On the other hand, the proportion of isolates of the non-pigmented, bile-resistant group obtained from abscesses was significantly lower than that not belonging to this group.

J Periodontal Res, 1991 May, 26(3 Pt 1), 184 - 90
Serological studies of Porphyromonas (Bacteroides) gingivalis and correlation with enzyme activity; Nagata A et al.; Porphyromonas gingivalis from the human oral cavity was serologically characterized using absorbed and unabsorbed rabbit antisera . The reference strains were ATCC 33277, W50, W83, 381 and hara 1 . The 432 isolates were from periodontal pockets of 63 patients with adult periodontitis . Using sonicated antigens, four serotypes were identified by immunodiffusion tests and immunoelectrophoresis . Each patient harbored only one serotype of P . gingivalis, and serotypes I and IV predominated . The incidence of serotype I was four times higher than that of serotype II, and approximately seven times higher than that of serotype III . The collagenolytic and some proteolytic enzymes of representatives of each serotype were assessed . Although all strains produced these enzymes to some degree, some differences in their levels were observed . Serotype II strains were more collagenolytic than serotypes I or III, and serotype III exhibited lower activities of N-CBz-glycyl-glycyl-arginyl peptidase than other serotypes . Antibiotic sensitivity was also compared with antimicrobial disks, and serotype IV strains exhibited high sensitivity to the four antibiotics used.

J Periodontal Res, 1991 May, 26(3 Pt 1), 167 - 75
Measurement of relative avidity of antibodies reactive with Porphyromonas (Bacteroides) gingivalis in the sera of subjects having adult periodontitis; Lopatin DE et al.; Relative avidities of antibodies to Porphyromonas (Bacteroides) gingivalis in the sera of 15 patients having adult periodontitis and 15 healthy subjects were evaluated using an ammonium thiocyanate-dissociated ELISA . Graded concentrations of ammonium thiocyanate were added to a single dilution of serum in order to dissociate low avidity antibody binding to P . gingivalis . The concentration of thiocyanate resulting in 50% reduction in binding (absorbance) was termed the ID50 for that serum . When IgG-class antibodies were examined, the ID50 of anti-P . gingivalis antibodies in the sera of patients was significantly elevated (0.96M vs 0.71M; p less than 0.01, Student's t-test) . In contrast, when IgM-class antibodies were examined no significant differences in ID50 between patients and controls were found for P . gingivalis (0.54M vs 0.53M) . While the ID50 values of patient antibodies were found to be elevated relative to those of healthy controls, comparison with antibodies from rabbits immunized with P . gingivalis and with ID50 values from other human studies suggests that adult humans, in general, produce very low-avidity antibodies to P . gingivalis . It is suggested that the presence of low-avidity antibodies contributes to the pathology associated with periodontal disease.

J Bacteriol, 1991 May, 173(9), 2962 - 8
Characterization of a neopullulanase and an alpha-glucosidase from Bacteroides thetaiotaomicron 95-1; Smith KA et al.; Previously, we constructed a gene disruption in the pullulanase I gene of Bacteroides thetaiotaomicron 5482A . This mutant, designated B . thetaiotaomicron 95-1, had a lower level of pullulanase specific activity than did wild-type B . thetaiotaomicron but still exhibited a substantial amount of pullulanase activity . Characterization of the remaining pullulanase activity present in B . thetaiotaomicron 95-1 has identified an alpha(1----4)-D-glucosidic bond cleaving pullulanase which has been tentatively designated a neopullulanase . The neopullulanase (pullulanase II) is a 70-kDa soluble protein which cleaves alpha(1----4)-D-glucosidic bonds in pullulan to produce panose . The neopullulanase also cleaved alpha(1----4) bonds in amylose and in oligosaccharides of maltotriose through maltoheptaose in chain length . An alpha-glucosidase from B . thetaiotaomicron 95-1 was characterized . The alpha-glucosidase was partially purified to a preparation containing three proteins of 80, 57, and 50 kDa . Pullulan and amylose were not hydrolyzed by the alpha-glucosidase . alpha(1----4)-D-Glucosidic oligosaccharides from maltose to maltoheptaose were hydrolyzed to glucose by the alpha-glucosidase . The alpha-glucosidase also hydrolyzed alpha(1----6)-linked oligosaccharides such as panose (the product of the pullulanase II action on pullulan) and isomaltotriose.

Vet Microbiol, 1991 May, 27(3-4), 283 - 93
The effect of dissociation of Bacteroides nodosus pili on their efficacy as a protective antigen against ovine footrot; Stewart DJ et al.; Previous studies have shown that pili from homologous Bacteroides nodosus provide protective immunity in sheep against footrot, whereas denatured pilin subunits are ineffective . The aim of the present study was to examine whether pili that were dissociated into pilin subunits under less vigorous, non-denaturing treatment conditions, would provide an effective level of protective immunity . Using the techniques of gel permeation chromatography, light scattering and susceptibility to proteolysis as measures of disruption, it was shown that pili were dissociated either by the neutral detergents n-octyl-beta-D-glucopyranoside (NOG) and Tween 80 or by lowering the pH with 1 M phosphoric acid to pH 2.2 . Circular dichroic spectra indicated, however that the samples were not denatured by these treatments . Electron microscopic monitoring of detergent dissociated material following exhaustive dialysis showed the presence of protein-detergent micelles and "in-line" aggregates which gave the appearance of short fibres . Within these monitored preparations, there was no evidence of native undissociated pili . Pili dissociated by NOG or acid were tested in protection trials and shown to provide protective immunity, although agglutination titres of serum taken from the vaccinated sheep were significantly lower than those of animals inoculated with intact pili.

Biochem Biophys Res Commun, 1991 Apr 15, 176(1), 505 - 10
Effects of a fecapentaene on protein kinase C; Hoshina S et al.; Protein kinase C (PKC) is a Ca2(+)- and phospholipid-dependent serine and threonine protein kinase which binds and is activated by tumor promoters such as the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA) . PKC can be activated in vitro by phosphatidylserine (PS) plus Ca2+ . We report here that the compound fecapentaene-12 can replace the requirement for PS in the activation of PKC by Ca2+ . In addition, at low concentrations fecapentaene-12 can enhance the activation of PKC by Ca2+ and PS . It can also either enhance or inhibit activation of PKC by the tumor promoter teleocidin, depending on the assay conditions . These results are of interest since fecapentaene is known to be a potent mutagen that is produced by Bacteroides species present in the lumen of the human colon . The present studies raise the possibility that this compound might also play a role in colon cancer by altering the activity of PKC.

J Dent, 1991 Apr, 19(2), 92 - 6
Evaluation of acrylic strips containing amoxycillin with clavulanic acid for local drug delivery; Abu Fanas SH et al.; The in vitro release of amoxycillin with clavulanic acid from acrylic strips at initial concentrations of 30, 40 and 50 per cent w/w was monitored using a double-beam ultraviolet spectrophotometer and compared with release of tetracycline hydrochloride . Highest levels of the antibacterial agents were released during the first 24 h period . Therapeutic levels of the drugs continued to be released during the subsequent 9 day period and were shown to be biologically active . Furthermore, for amoxycillin with clavulanic acid, an initial concentration of 40 per cent gave the highest level of release on day 10; while, for tetracycline, 50 per cent provided the highest level of release . Local application of 40 per cent amoxycillin with clavulanic acid incorporated into acrylic strips placed in periodontal pockets in patients with established periodontitis produced a marked change in the subgingival microflora as monitored by dark-field microscopy and cultural techniques . These changes in the subgingival flora were concomitant with elimination of bleeding on probing at the treated sites and were still evident 3 weeks after removal of the acrylic strips . The sensitivity of Bacteroides gingivalis (syn . Porphyromonas gingivalis) and Bacteroides intermedius (syn . Prevotella intermedia) isolated before and after treatment to amoxycillin with clavulanic acid remained unchanged.

J Periodontol, 1991 Apr, 62(4), 247 - 57
Effects of metronidazole on periodontal treatment needs; Loesche WJ et al.; Periodontitis, a common cause of tooth loss in adult populations, is an inflammatory response to the overgrowth of anaerobic organisms such as spirochetes and bacteroides and, in some cases, micro-aerophilic organisms in the subgingival plaque . In the present investigation, using a double-blind clinical design, we sought to determine whether 1 week of metronidazole treatment plus debridement of the tooth surfaces was superior to 1 week of placebo treatment plus debridement (positive control) in reducing the subsequent amount of periodontal surgery given to the patients . Thirty-nine patients were randomly assigned to either the metronidazole or placebo (positive control) groups . All patients were given the necessary scaling and root planing and were unsupervised in their usage of the medication . After the completion of this treatment, they were reexamined and it was found that the metronidazole regimen caused a significant reduction in surgical needs of about 5 teeth per patient compared to the positive control (difference before and after treatment 8.3 +/- 6.8 teeth metronidazole versus 2.9 +/- 4.8 positive control, P = 0.007) . The difference between groups was maintained during the 2 to 3 years' recall period . Metronidazole had a significant effect on the site specific reduction of spirochetes: 90% of the sites in the metronidazole group versus 64% in the positive-control group had a decrease in the percentage of spirochetes (P less than 0.05) . We conclude that systemic metronidazole given 250 mg tid for 7 days in conjunction with debridement of the tooth surfaces can significantly reduce the need for periodontal surgery compared to the standard regimen which included only debridement.

Clin Orthop, 1991 Apr, (265), 297 - 301
Anaerobic osteomyelitis . A new experimental rabbit model; Johansson A et al.; Experimental studies of osteomyelitis have been hampered by methodologic problems . For inducing experimental anaerobic osteomyelitis, the medullary cavity of the proximal tibial metaphysis of five New Zealand white rabbits was excavated and filled with a polyvinyl alcohol sponge . On the right side, 1 ml of a suspension containing Bacteroides fragilis (10(7) colony-forming units/ml) was injected, while on the left side, Ringer's solution was used as a control substance . Within five weeks, all animals developed clinical signs of osteomyelitis . The findings were verified by roentgenograms and bone scans . There was a significant rise in titers against the inoculated B . fragilis strain in every rabbit, and when killed at 18 weeks after the bacterial inoculation cultures containing the inoculated strain were obtained from all animals . No other bacterial strains were isolated . With one exception, cultures were positive in samples from both the inoculated and the control side, indicating hematogenous seeding . In one animal, the cultures from the inoculated side were negative, whereas on the control side, there was significant growth of the inoculated strain . Histologic examination of the infection sites showed low-grade chronic osteitis . In contrast to previous studies, which have indicated severe difficulty in obtaining a single-strain anaerobic osteomyelitis, the present method gives a high infection rate with reproducible immunologic, roentgenographic, and histologic reactions.

Infect Immun, 1991 Apr, 59(4), 1255 - 63
A novel mouse model to study the virulence of and host response to Porphyromonas (Bacteroides) gingivalis; Genco CA et al.; We describe here the development of a mouse subcutaneous chamber model that allows for the examination of host-parasite interactions as well as the determination of gross pathology with Porphyromonas (Bacteroides) gingivalis challenge . When inoculated into stainless-steel chambers implanted subcutaneously in female BALB/c mice, P . gingivalis W83, W50, and A7436 (10(8) to 10(10) CFU) caused cachexia, ruffling, general erythema and phlegmonous, ulcerated, necrotic lesions, and death . P . gingivalis W50/BEI, HG405, and 33277 (10(10) CFU) produced localized abscesses in the mouse chamber model with rejection of chambers at the injection site . Analysis of chamber fluid from 33277-, HG405-, and W50/BEI-infected mice by cytocentrifugation revealed inflammatory cell debris, polymorphonuclear leukocytes, and high numbers of dead bacteria . In contrast, fluid from A7436-, W50-, and W83-infected mice revealed infiltration predominantly of polymorphonuclear leukocytes and live bacteria . Bacteria were found primarily associated with polymorphonuclear leukocytes in the fluid from W50-, HG405-, and W83-infected mice but not from A7436-infected mice . Viable isolates were recoverable from the chamber fluid through day 3 for W50/BEI, day 5 for 33277, day 6 for HG405, day 7 for W50, day 14 for W83, and day 26 for A7436 . All strains induced a systemic immunoglobulin G response in serum and chamber fluid samples . The use of this model will allow us to examine the virulence of P . gingivalis as defined by the interaction of host response to localized infection with P . gingivalis.

Oral Microbiol Immunol, 1991 Apr, 6(2), 81 - 7
DNA probe detection of Eikenella corrodens, Wolinella recta and Fusobacterium nucleatum in subgingival plaque; Lippke JA et al.; This cross-sectional study used species-specific DNA probes to examine subgingival plaque specimens for the presence of Eikenella corrodens, Wolinella recta, and Fusobacterium nucleatum in adults with untreated periodontitis or gingivitis and in healthy controls . W . recta and F . nucleatum were more prevalent in diseased sites from the periodontitis group when compared with the controls (81% vs 22% and 83% vs 20% respectively) . E . corrodens was detected in 62% of the control sites and 81% of the periodontitis sites . Because the control sites commonly contained this organism, E . corrodens may not be useful in differentiating between health and disease . In addition, the relationship between the prevalence of W . recta and F . nucleatum and the prevalence of the established periodontal pathogens, Actinobacillus actinomycetemcomitans, Bacteroides intermedius and Bacteroides gingivalis, was examined . Positive detection of W . recta and F . nucleatum correlated closely with the presence of A . actinomycetemcomitans, B . intermedius and B . gingivalis . Therefore, W . recta and F . nucleatum do not appear to be unique indicators of periodontal disease.

Oral Microbiol Immunol, 1991 Apr, 6(2), 111 - 4
Rapid antimicrobial resistance screening method for Bacteroides intermedius; Calsina G et al.; The purpose of the study was to validate a rapid resistance screening (RRS) method for antimicrobial susceptibility testing of a selected periodontopathic microorganism using the standard broth dilution method as a control . Twenty-five subgingival plaque samples from gingivitis or periodontitis sites were plated on Trypticase soy agar supplemented with 5% rabbit blood with antibiotic discs (RRS method) and without (control) . The antibiotics tested were: Augmentin, clindamycin, erythromycin, metronidazole, penicillin G and tetracycline hydrochloride . Bacteroides intermedius isolated from both groups of plates were placed onto antibiotic supplemented Trypticase soy broth . The antibiotic susceptibilities of B . intermedius isolated from the plates with antibiotic discs and the standard broth method were compared . The results showed high sensitivity and predictability for the RRS method compared with the control . The percentage of agreement was: 100% for Augmentin 30 micrograms, clindamycin 2 micrograms and tetracycline 30 micrograms; 96% for erythromycin 15 micrograms, metronidazole 80 micrograms and penicillin 10 IU; 92% for penicillin 2 IU; 88% for erythromycin 2 micrograms and 84% for tetracycline 5 micrograms . The results of this study document the feasibility of the RRS method for testing antimicrobial resistance of whole samples if its efficacy can be demonstrated for other bacteria . This method may be a quick and useful test for the periodontal practitioner in determining the antibiotic susceptibility of periodontal plaque pathogens.

J Bacteriol, 1991 Apr, 173(8), 2581 - 9
Adhesion of Actinomyces viscosus to Porphyromonas (Bacteroides) gingivalis-coated hexadecane droplets; Rosenberg M et al.; Interbacterial adhesion (coadhesion) is considered a major determinant of dental plaque ecology . In this report, we studied several aspects of the adhesion of Porphyromonas (Bacteroides) gingivalis to hexadecane in order to use the liquid hydrocarbon as a convenient substratum for coadhesion assays . Washed suspensions of hydrophobic P . gingivalis 2561 cells were vortexed with hexadecane to yield highly stable cell-coated droplets . Kinetics of coadhesion between Actinomyces viscosus cells and P . gingivalis-coated hexadecane droplets (PCHD) was subsequently studied . Aliquots of PCHD were added to A . viscosus suspensions, and the mixtures were gently rotated . Avid adhesion of A . viscosus cells to the immobilized P . gingivalis layer could be readily measured by the decrease in turbidity in the aqueous phase, following phase separation . Despite the ability of A . viscosus cells to adsorb to hexadecane following vigorous mixing, gentle mixing did not appreciably promote adhesion to bare hexadecane . Moreover, extensive microscopic examinations revealed that A . viscosus cells adhered exclusively to the bound P . gingivalis cells rather than to exposed areas of hexadecane . Coadhesion of A . viscosus to the PCHD appeared to follow first-order kinetics, attaining 80% levels within 30 min . Electron micrographs revealed A . viscosus cells adhering to the P . gingivalis cell layer adsorbed at the hexadecane-water interface . Interestingly, P . gingivalis cells did not appear to penetrate the hexadecane . A viscosus mutants lacking type 1 or type 2 fimbriae or both were still able to bind to the PCHD . No obvious correlation was observed between relative hydrophobicity of A . viscosus strains and their binding to PCHD . However, defatted bovine serum albumin, an inhibitor of hydrophobic interactions, was the most potent inhibitor among those tested . The data suggest that this approach provides a simple, quantitative technique for studying kinetics of bacterial coadhesion which is amenable to both light and electron microscopic observation.

J Clin Microbiol, 1991 Apr, 29(4), 723 - 5
Chronic conjunctivitis caused by oral anaerobes and effectively treated with systemic metronidazole plus amoxicillin; van Winkelhoff AJ et al.; In this study, we report on a case of refractory, unilateral anaerobic conjunctivitis . The predominant anaerobic flora consisted of Prevotella intermedia (formerly Bacteroides intermedius) and Peptostreptococcus micros . By using the technique of restriction endonuclease fingerprinting of genomic DNA, it was shown that the P . intermedia likely originated from the oral cavity . Topically applied antibiotics had failed to suppress the infection in the past . Successful treatment was achieved after systemic administration of metronidazole plus amoxicillin.

Antonie Van Leeuwenhoek, 1991 Apr, 59(3), 191 - 8
Fermentation of L-tartrate by a newly isolated gram-negative glycolytic bacterium; Janssen PH; Enrichments on L-tartrate from a freshwater lake sediment yielded a pure culture of anaerobic bacterium designated strain 16Lt1 . The rod-shaped organism was motile, did not form spores, and had a gram-negative wall structure . No cytochromes were detected . The mol % G + C of the DNA was 58 . The new strain was microaerotolerant, and grew optimally at 30 degrees C and neutral pH in freshwater medium . A wide range of carbohydrates was fermented, with formate, acetate, ethanol, lactate and succinate being the end-products detected . L-tartrate and citrate were fermented to formate, acetate and CO2 . L-tartrate was fermented by the dehydratase pathway, and glucose by the Embden-Meyerhof-Parnas pathway . Fumarate was reduced, but nitrate, sulfate, sulfur and thiosulfate were not used as terminal electron acceptors . Glucose metabolism was constitutive, whereas L-tartrate-degrading activity was inducible . When glucose and L-tartrate were both present as substrates, growth was diauxic with glucose being metabolized first . The growth rate and growth yield were higher on glucose than on L-tartrate . Strain 16Lt1 has been deposited with the Deutsche Sammlung von Mikroorganismen as 'Bacteroides' sp . DSM6268.

Enferm Infecc Microbiol Clin, 1991 Apr, 9(4), 214 - 8
{Evolution of the sensitivity of Bacteroides group fragilis at the Sevilla University Hospital (1983-1987)}; Borobio MV et al.; The evolution of antimicrobial susceptibility of Bacteroides fragilis over a five year period is described . We have studied 30 selected strains isolated each year at the University Hospital of Sevilla (total: 150 strains) . We did not find any resistant strain to chloramphenicol, metronidazole or imipenem . Resistance to piperacillin (8%) and cefoxitin (13%) remain constant over the study period . Resistance to cefmetazole, cefotaxime, mezlocillin, ofloxacin, clindamycin and moxalactam ranges from 24% to 37% . A rise in the percentage of resistant strains to ticarcillin (from 17% to 30%) and ceftizoxime (from 0% to 40%) was also seen during the study period . Bacteroides thetaiotaomicron was the overall more resistant species, and B . fragilis the more sensitive.

Roum Arch Microbiol Immunol, 1991 Apr-Jun, 50(2), 95 - 108
Detection of Bacteroides fragilis group by immunofluorescence; Radu I et al.; The following strains: B . fragilis subspecies thetaiotaomicron (A); B . fragilis subspecies fragilis strain E-1, E-2, M, St., Se., Ni., 8, 16; B . fragilis subspecies distasonis 145 (D) were serologically studied by immunofluorescence as compared to agglutination . Anti-B . fragilis sera titration by immunofluorescence (IF) reaction, as compared to agglutination reaction in tube, was more sensitive (2-16 times higher titers), specific and reproducible . Among the organisms from B . fragilis group, species, subspecies and even train specificity was noticed . Also, the possibility for rapid identification of anaerobic organisms, belonging to B . fragilis group, in pathologic products obtained from experimentally infected animals (mice and rats), by IF reaction, in comparison with classic methods (anaerobic cultures and biochemical determinations) was studied . Of 87 studied animals, 61 proved positive by cultures and 59 by IF; 56 animals were shown positive and 23 animals proved negative by both methods (intermethods concordance in 79 cases) . Statistical analysis of IF results provided the following: method sensitivity (detection capacity of real-positive cases)-91.80%; method specificity (detection capacity of real-negative cases)-88.46%; false-positive cases-11.53%; false-negative cases-8.19% . Immunofluorescence proved specific, sensitive, practical and rapid method detection of non-sporulated anaerobic organisms species and subspecies belonging to Bacteroides fragilis group.

Can J Vet Res, 1991 Apr, 55(2), 117 - 20
Monoclonal antibodies against pili of serologically distinct Bacteroides nodosus; Gradin JL et al.; Several monoclonal antibodies (McAbs) against pili of Bacteroides nodosus were examined to determine their reactivity with 11 different serotypes . One McAb was identified by enzyme-linked immunosorbent assay (ELISA) analysis that bound to nine of the 11 serotypes and another that bound to the remaining two serotypes tested . In addition, some McAbs demonstrated specificity for a single serotype, while others displayed specificities for up to five other serotypes . Comparison of immunoblot analysis with the ELISA revealed that the former method was not as sensitive in that all McAbs positive by the ELISA, were not positive by immunoblot . Possible explanations of these findings are discussed . There appear to be several antigenic determinants on B . nodosus pili and considerable sharing of these determinants between pili types . The 11 serotypes analyzed by the McAbs in this report are representative of all 20 US serotypes as well as the A-set and D-set categories of Australia . Therefore, the two epitopes recognized by two of the McAbs reported herein encompass all of the currently characterized B . nodosus serotypes and may provide a basis for bivalent vaccines efficacious for all types of B . nodosus induced footrot in sheep.

Dig Dis Sci, 1991 Apr, 36(4), 461 - 70
Inflammatory bowel disease induced by combined bacterial immunization and oral carrageenan in guinea pigs . Model development, histopathology, and effects of sulfasalazine; Oestreicher P et al.; A model of experimentally induced inflammatory bowel disease (IBD) featuring colitis, originally devised by Onderdonk and co-workers in guinea pigs, was modified to establish the optimal conditions for ulcer development . Upon varying the time of subcutaneous immunization with Bacteroides vulgatus and concomitant oral administration of acid-degraded iota-carrageenan and viable B . vulgatus, it was found that the optimal times of administering these agents were one to two weeks and five to six days, respectively . Light microscopy of the colon and cecum of the guinea pigs given the optimized treatment for ulcer induction revealed pronounced edema, inflammation, and lesions of the mucosa . Transmission electron microscopy of the mucosa from these animals showed the presence of large numbers of leukocytes in the subepithelial region, the majority being polymorphonuclear neutrophils which possessed large electron-dense granules or rods . Oral administration of 300 mg/kg/day sulfasalazine (salicylazosulfapyridine) for 14 days to guinea pigs given the optimized treatment for ulcer induction failed to reduce the numbers of ulcers or the histopathology gradings and fine structural changes of the mucosal inflammatory changes, but did reduce the symptoms of diarrhea.

Oral Microbiol Immunol, 1991 Apr, 6(2), 102 - 6
Variance in recovery of periodontitis-associated bacteria caused by sampling technique and laboratory processing; Wikstrom M et al.; The influence of sampling procedure and of laboratory processing on the recovery of Bacteroides gingivalis, Bacteroides intermedius, and Actinobacillus antinomycetemcomitans from periodontitis sites was evaluated . Thirty-three adult subjects with severe periodontitis participated in the study . In all, 462 samples from 81 sites were examined . The samples were taken using the paper point technique . The cultivations were performed by use of enriched Brucella agar for determination of total colony-forming units and Bacteroides species, and trypticase soy bean agar for determination of A . actinomycetemcomitans . The risk of getting a false negative result was 4% for B . gingivalis, 20% for B . intermedius, and 38% for A . actinomycetemcomitans . It was considerably reduced if duplicate samples were taken . The sampling procedure alone explained up to 98% of the false-negative results.

J Am Vet Med Assoc, 1991 Mar 15, 198(6), 1045 - 8
Clinical use of metronidazole in horses: 200 cases (1984-1989); Sweeney RW et al.; Case records of 200 horses treated with metronidazole were reviewed . Horses were treated for respiratory tract infections (90 cases), peritonitis or abdominal abscess (39 cases), celiotomy (49 cases), orthopedic infections (6 cases), and miscellaneous soft tissue infections (16 cases) . Bacteria of the genus Bacteroides were most prevalent (55 of 167 anaerobic isolates) . Metronidazole was always used in combination with other antimicrobial drugs . Only 4 of the 200 horses had signs of adverse effects associated with metronidazole treatment . Those 4 horses had poor appetite that resolved when metronidazole treatment was discontinued.

Biochem Biophys Res Commun, 1991 Mar 15, 175(2), 713 - 9
Purification, characterization and immunolocalization of fimbrial protein from Porphyromonas (bacteroides) gingivalis; Sojar HT et al.; Rapid and reproducible method is described here for the purification of the 43 kDa fimbrial protein from P . gingivalis by preferential fractionation in the presence of 1% SDS and 0.2M of a bivalent cation at pH 6.5 . Homogeneity of the purified 43 kDa was confirmed by SDS-PAGE and Western blot analysis using monoclonal and polyclonal antibodies raised against this protein . Amino acid composition and the amino acid sequence of the first 30 amino acid residues of the purified fimbriae are consistent with the composition and sequence predicted from the cloned gene of the fimbrial subunit . Circular dichroism spectra shows high levels of beta-sheet structure . The purified 43 kDa polymer shows fimbriae-like morphology under the electron microscope . Ultrastructural localization of the 43 kDa protein by the immunogold technique revealed specific labeling of the fimbriae with a diameter of approximately 3.5 to 5.0 nm . Localization of this protein suggest that the 43 kDa component is a fimbrial subunit.

Tohoku J Exp Med, 1991 Mar, 163(3), 175 - 85
Effect of a platelet activating factor antagonist and antithrombin III on septicemia and endotoxemia in rats; Inoue Y et al.; Disseminated intravascular coagulation (DIC) or renal damage associated with septicemia was induced in rats by ligating the cecum or by injecting endotoxin . In the septicemia model, the number of E . coli and Bacteroides spp in the blood increased concomitantly with an increase of endotoxin . In this model the development of hypercoagulability with mild fibrinolysis was observed . Histopathologic findings in the kidneys, including the formation of microthrombi in the glomeruli and the vacuolization and dilatation of renal tubular cells, suggest the development of mild DIC . In the endotoxin-induced DIC model, both remarkable state of hypercoagulability and fibrinolysis were observed with fibrin thrombi in glomeruli . The administration of the platelet-activating factor antagonist, CV-6209, or of human antithrombin III, ameliorated DIC significantly by limiting the increases in prothrombin time, activated partial thromboplastin time and fibrin degradation products . These agents significantly reduced the deposition of fibrin in the glomeruli and significantly prolonged the survival time of the endotoxin injected rats . These observations suggest that the PAF antagonist CV-6209 and ATIII merit clinical evaluation in the management of DIC caused by septisemia.

Infection, 1991 Mar-Apr, 19(2), 101 - 5
Comparative efficacies of ticarcillin, ticarcillin/clavulanic acid, piperacillin and cefoxitin against polymicrobial infections in mice caused by Escherichia coli and Bacteroides fragilis; Beale AS et al.; A model of localised abscess formation was used to establish mixed infections caused by Escherichia coli and Bacteroides fragilis . The beta-lactamase producing, ticarcillin-resistant strains E . coli E96 and B . fragilis VPI 8708 were used to produce one infection, and in another infection, a beta-lactamase hyperproducing strain E . coli 41548 was combined with a ticarcillin-susceptible strain, B . fragilis B3 . Treatment, at doses producing clinically achievable concentrations in mouse serum, began 1 h after inoculation, and continued three times daily for four days . Bacterial numbers in infected tissue were measured at intervals . Against both infections, ticarcillin was ineffective in preventing bacterial growth and abscess formation in all mice . Piperacillin prevented abscess formation in 60% of the mice infected with E . coli E96/B . fragilis VPI 8708, and in 40% of those in the E . coli 41548/B . fragilis B3 group . Therapy with ticarcillin/clavulanic acid or cefoxitin reduced the number of both organisms at the site of infection, and thus prevented abscess formation in 100% treated animals.

Int J STD AIDS, 1991 Mar-Apr, 2(2), 102 - 4
Anaerobic vaginosis: study of male sexual partners; Arumainayagam JT et al.; One hundred male sexual partners of women with anaerobic vaginosis (AV) were screened for the presence of sexually transmitted diseases (STD) . Thirty male partners had evidence of non-gonococcal urethritis (NGU), compared to 5 in the control group (P less than 0.05) . Chlamydia trachomatis was isolated from 14 male partners, compared to 3 in the control group . Forty-five male partners required treatment for STDs, compared to 11 in the control group (P less than 0.02) . Nine (40%) male partners with chlamydia-negative NGU were successfully treated with metronidazole alone while 10 required Deteclo in addition . There was no significant association between Bacteroides ureolyticus and chlamydia-negative NGU . Screening of male partners resulted in the treatment of STDs in 62 additional patients who would have otherwise not received treatment . The results suggest that examination of male partners of women with AV results in an increased yield of STD diagnoses.

J Appl Bacteriol, 1991 Mar, 70(3), 245 - 52
The hydrolysis of lucerne cell-wall monosaccharide components by monocultures or pair combinations of defined ruminal bacteria; Miron J; The defined ruminal bacterial strains Fibrobacter succinogenes S85, Ruminococcus flavefaciens FD1, Ruminococcus albus 7, Butyrivibrio fibrisolvens D1, and Bacteroides ruminicola GA33 were grown, in monocultures or as combinations of pair strains, on isolated lucerne cell-walls (CW) as the sole carbohydrate substrate . Fibrobacter succinogenes S85 was the dominant strain determining extent of CW hydrolysis in all combinations with S85 . The hydrolysis of cellulose, xylan, hemicellulose side-sugars, and total CW monosaccharides by pure S85 were: 58.8, 47.3, 66.9 and 57.0%, respectively . The strains combination S85 plus D1 comprised the highest complementary effect, increasing significantly the hydrolysis of cellulose and total CW monosaccharides by 16% and 13%, respectively, above the values obtained by pure S85 . This complementation was expressed also in growth pattern of bacteria . The monocultures of FD1, D1 and GA33 had very little hydrolytic effect on lucerne cellulose, but higher effects on xylan and hemicellulose side-sugars . The combinations D1 plus GA33 and 7 plus GA33 were complementary in the hydrolysis of all CW polysaccharides . The combinations FD1 plus D1, FD1 plus GA33, and 7 plus D1 were complementary only with respect to hemicellulose hydrolysis . On the other hand, the cellulolytic combinations S85 plus FD1, S85 plus 7 and FD1 plus 7 demonstrated negative interactions in lucerne CW polysaccharides hydrolysis . Under scanning electron microscopy (SEM), S85 comprised the most dense layer of bacterial cell mass attached to and colonized on CW particles . The cell surface topology of the cellulolytic strains S85, FD1 and 7 attached to CW particles was specified by a coat of characteristic protuberant structures.

J Appl Bacteriol, 1991 Mar, 70(3), 216 - 20
Rapid differentiation of the species of the genus Bacteroides sensu stricto by capillary gas chromatography of cellular carbohydrates; Engelhard E et al.; Whole-cell hydrolysates of Bacteroides fragilis, the type species of the genus Bacteroides Castellani and Chalmers 1919, and the genetical closely related species B . vulgatus, B . ovatus, B . eggerthii, B . distasonis, B . uniformis, B . thetaiotaomicron, B . stercoris, B . merdae, and B . caccae were used to determine characteristic carbohydrate patterns by capillary gas chromatography . On the basis of the chemical derivatization of the carbohydrates seven characteristic peaks for peracetylated aldononitriles and nine characteristic peaks for peracetylated o-methyloximes were selected from the carbohydrate fingerprints of the reference strains to prepare a dichotomous identification key . The classification of an unknown strain supposed to belong to the formerly called 'Bacteroides fragilis group' is possible with this key . Some of the advantages of the technique were that the identification of Bacteroides fragilis-like strains requires only 4-5 h after primary isolation and that the bacteria can be exposed to oxygen because viability of the organisms is not necessary . Sophisticated anaerobic techniques can therefore be avoided for identification.

J Periodontol, 1991 Mar, 62(3), 197 - 202
A randomized, placebo-controlled trial of doxycycline: effect on the microflora of recurrent periodontitis lesions in high risk patients; Kulkarni GV et al.; Twenty-seven patients with a recent history of periodontal abscesses and/or loss of gingival attachment level (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial . Clinical measurements and subgingival scaling were performed every 2 months . When a site exhibited greater than or equal to 2 mm loss of GAL or a periodontal abscess, patients were administered either doxycycline at a dosage of 200 mg to start and 100 mg per day for 3 weeks, or a placebo . Clinical measurements of GAL and microbial analysis of subgingival plaque at study and control sites were made at the time of active disease and at intervals of 1 week and 7 months after completion of the drug regime . Plaque samples were screened for the presence of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Bacteroides intermedius (Bi), Eikenella corrodens (Ec) and Fusobacterium nucleatum (Fn) by indirect immunofluorescence antibody technique and for spirochetes (Sp) using Ryu's stain . Based on presence or absence analysis of the sum scores of the 6 pathogens, both the placebo (n = 10) and the doxycycline groups (n = 17) exhibited similar scores at the time of detection of active disease (mean placebo = 2.38 +/- 0.32; mean doxycycline = 2.95 +/- 0.27; P = 0.18) . One week after treatment, the probability of detection was unchanged in the placebo group (mean placebo = 3.14 +/- 0.47), but was significantly reduced in the doxycycline group (mean doxycycline = 1.77 +/- 0.26; P = 0.0002) . Study (active) sites exhibited scores 2 to 3 times higher than control (inactive) sites before doxycycline treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Ann Surg, 1991 Mar, 213(3), 253 - 60
The peritoneal environment during infection . The effect of monomicrobial and polymicrobial bacteria on pO2 and pH; Sawyer RG et al.; Intraperitoneal (IP) abscesses frequently are composed of aerobes and anaerobes, and, in experimental models, a particulate adjuvant . The environmental changes effected by these components, either singularly or in combination, have not been well defined . The IP pO2, pH, and recoverable bacteria from the peritoneum of rats were quantified over 6 hours during simple aerobic and anaerobic infections and during mixed peritonitis with and without a sterile feces-barium sulfate adjuvant (SFA) . Fourteen groups were studied, receiving intraperitoneally, at time of oxygen probe placement, 1 mL normal saline (control), Escherichia coli (EC), Bacteroides fragilis (BF), SFA alone, or a mixture of EC and BF, EC and SFA, BF and SFA, or EC, BF, and SFA . Control animals exhibited a stable IP pO2 and pH during 6 hours . In monomicrobial EC peritonitis, inocula well below the LD50 produced an increased IP pO2 and reduced arterial-peritoneal gradient (APG), with a stable IP pH . By 6 hours lethal doses of EC produced a dramatic decline in IP pO2, with no change in arterial pO2 as well as acidic IP and arterial pHs . Simple BF peritonitis caused no or minor elevations in IP and arterial pO2 with no change in pH . During mixed infections a significant decline in the IP pO2 and pH at 6 hours in those groups infected with both SFA and EC of a moderate, normally sublethal inoculation was observed, while arterial pO2 was unchanged and arterial pH was decreased only slightly . Concomitantly there was a significant increased number of aerobic bacteria in those groups with SFA as adjuvant compared to similar inocula without SFA . This study demonstrates the complex interactions of bacteria, sterile particulate adjuvant (SFA), and the host peritoneum . It suggests that the combination of SFA and aerobic bacteria alter the peritoneal environment to one permitting anaerobic growth and promoting abscess formation.

J Infect Dis, 1991 Mar, 163(3), 664 - 7
Preexposure of the peritoneum to live bacteria increases later mixed intraabdominal abscess formation and delays mortality; Sawyer RG et al.; Intraabdominal infections are a major source of morbidity and mortality for the trauma and postoperative patient . Transient peritoneal contamination with bacteria after either intentional or unintentional violation of the gut are common . The effect of this intermittent antigen exposure upon later formation of intraabdominal abscesses is unclear . Previous experiments by others have demonstrated that repeated exposure to Bacteroides fragilis capsular polysaccharide can induce a T lymphocyte-mediated immunity to subsequent induction of pure B . fragilis abscess formation . In a murine mixed intraabdominal abscess model, preexposure to live Escherichia coli, B . fragilis, or both increased the number of later abscesses and in some cases their bacterial composition . Further, immunization with E . coli alone increased late mortality without altering overall mortality . These data suggest that the alterations of immune function produced by live, transient bacteria upon subsequent mixed intraabdominal abscess induction result in fundamentally different consequences from those observed after specific polysaccharide antigen exposure and subsequent monomicrobial abscess induction.

Indian J Med Res, 1991 Mar, 93, 98 - 102
Rapid identification of clinically important bacteroides by coagglutination method; Lalitha MK et al.; A coagglutination technique using indigenous reagents was applied for the rapid identification of Bacteroides fragilis and the black pigmented bacteroides group, using colony suspensions . All the 58 strains of B . fragilis and 42 strains of black pigmented bacteroides tested could be correctly identified by this method . The specificity of the coagglutination reagent was confirmed by the absence of cross reactivity with the related species of bacteroides, viz., B . distasonis, B . ovatus, B . vulgatus and B . thetaiotaomicron as well as other anaerobic and aerobic bacteria . A panel of four antisera against B . fragilis was required for correct identification of the strains tested, indicating the presence of multiple serotypes . On the other hand, all 42 strains of black pigmented bacteroides tested could be identified, using a single reagent as these strains appeared to have no antigenic type variants.

Zhonghua Kou Qiang Yi Xue Za Zhi, 1991 Mar, 26(2), 70 - 2, 126
{The correlation of black-pigmented bacteroides spp to symptoms associated with apical periodontitis}; Chen H; The quantitative analysis of the incidence of black-pigmented Bacteroides (B.P.B.) spp . in 80 human dental root canal infections (56 with acute symptoms and 24 clinically asymptomatic) in 79 adults were studied . Altogether 101 strains including 7 species of B . P . B . were identified . It was found that the infection rate of B . P . B . in symptomatic group (192.86%) was higher than that in asymptomatic group (41.67%) . The means of quantity of cultivable B . P . B . (CFU/ml) and percentage of B.P.B . (CFU/ml) in total CFU/ml of bacteria were not significant . But the percentage of asacchrolytic B.P.B . species in B.P.B . positive samples in symptomatic group (73.08%) was higher than that in B.P.B . positive samples in asymptomatic group (40%) . These results suggest that there is a close correlation between symptoms and the asacchrolytic species of B . endodontalis and B . gingivalis.

Mol Microbiol, 1991 Mar, 5(3), 543 - 60
Organization of the fimbrial gene region of Bacteroides nodosus: class I and class II strains; Hobbs M et al.; The fimbrial subunit genes of Bacteroides nodosus may be divided into two distinct classes, based on the sequence of the major subunit gene fimA (accompanying paper--Mattick et al., 1991) . The genetic organization of the fibrial gene region in these two classes is also distinct . Upstream of fimA in both classes in opposite transcriptional orientation is the gene aroA which encodes amino acid biosynthetic enzyme 5-enolpyruvylshikimate-3-phosphate synthase . However, downstream of fimA the two classes are quite different until homology is restored at a bidirectional transcription termination signal separating the fimbrial operon from a gene clpB, which appears to encode the regulatory subunit of an ATP-dependent protease . Between aroA and clpB class I strains contain, apart from fimA, only one other gene (fimB) . Sequence and polymerase chain reaction analyses indicate that fimB does not have a separate promoter but rather is co-transcribed with fimA at a level attenuated by the strength of the transcription termination signal in the intergenic region . In class II strains fimA is followed by a more extended region containing three genes, which appear to have the same transcriptional arrangement as fimB . The second of these genes (fimD) may represent a functional analogue of fimB although there is no close sequence homology . The first gene (fimC) has no obvious similarity to either fimB or fimD . Beyond fimD, at the 3' end of the class II-specific region, is a variant fimbrial subunit gene (fimZ) which is virtually identical in serogroups D and H and which appears to represent a duplicate, possibly redundant, gene closely related to the progenitor of the more divergent structural subunit fimA gene found in these strains . Comparisons of the predicted fimZ product with those of fimA in class I and class II strains, as well as of the boundaries of the class-specific regions, suggest that the class II sequences evolved in another type 4 fimbriate species and were subsequently substituted in the B . nodosus genome by lateral transfer . Analysis of the sequences flanking fimA in different strains indicates that recombinational exchange of both fimA and the entire operon has also occurred between strains, and is possibly a mechanism for disseminating structural diversity in the population.

Gene, 1991 Mar 1, 99(1), 115 - 9
Sequence of fimbrial subunit-encoding genes from virulent and benign isolates of Dichelobacter (Bacteroides) nodosus; Billington SJ et al.; Both virulent and benign isolates of the ovine pathogen Dichelobacter (Bacteroides) nodosus produce polar fimbriae which have been implicated in twitching motility . The fimbrial subunit-encoding genes from two virulent and two benign serogroup-B isolates of D . nodosus were cloned and sequenced . Analysis of the deduced amino acid (aa) sequences of these subunits indicated the presence of substitutions that appeared to correlate with the virulence phenotype . However, these aa substitutions were located in variable regions of the protein where they are unlikely to alter the functional properties of the fimbriae . The aa sequences of the serogroup-B subunits had a very high level (91-95%) of similarity, particularly at the N terminus, where the conserved region extended up to aa 61 . Specific aa substitutions within the subunit of one isolate may reflect its serotypic variation from the other serogroup-B subunits studied.

Plasmid, 1991 Mar, 25(2), 141 - 4
Identification and DNA sequence of a new Bacteroides fragilis insertion sequence-like element; Rasmussen BA et al.; A new Bacteroides fragilis insertion sequence (IS)-like element has been identified, cloned, and sequenced . The element is 1598 base pairs in length . It is flanked by a 15-base pair imperfect inverted repeat and contains a large open reading frame which could encode a 430 amino acid protein . There is an 8-base pair duplication of genomic DNA sequences at the site of integration . One copy of the IS-like element is integrated within the 5' upstream sequence of the metallo-beta-lactamase gene ccrA, cloned from B . fragilis TAL3636 . The IS-like element is integrated 19 bp upstream of the predicted initiation codon and, therefore, probably provides the transcriptional start signals for the CcrA gene.

J Parodontol, 1991 Feb, 10(1), 77 - 91
{Bacterial periodontal plaque in childhood . Literature review}; Robert JC et al.; Bacterial colonization is investigated: before eruption, in primary dentition, mixed dentition and permanent dentition, with and without gingival inflammation . Microorganisms such as spirochetes and Black pigmented Bacteroides are implicated in the periodontal disease . These germs arrive later than teeth and their importance grows with age and gingival inflammation . Different reviews have emphasised the potential role of specific pathogens in the aetiology of periodontitis . The plaque composition of necrotizing ulcerative gingivitis and periodontitis in their pre and post pubertal forms, localized and generalized is investigated . A actinomycetemcomitans, B . intermedius and spirochetes can be isolated from children having destructive periodontal disease . Changes in flora can then be explained.

Can J Microbiol, 1991 Feb, 37(2), 141 - 7
Cellobiose uptake by the cellulolytic ruminal anaerobe Fibrobacter (Bacteroides) succinogenes; Maas LK et al.; Cellobiose transport by the cellulolytic ruminal anaerobe Fibrobacter (Bacteroides) succinogenes was measured using randomly tritiated cellobiose . When assayed at the same concentration (1 mM), total cellobiose uptake was one-fourth to one-third that of total glucose uptake . The abilities of F . succinogenes to transport cellobiose or glucose were not affected by the sugar on which the cells were grown . Aspects of the simultaneous transport of {14C(U)}glucose and {3H(G)}cellobiose, the failure of high concentrations of cold glucose to compete with hypothetical {3H(G)}glucose (derived externally from {3H(G)}cellobiose), and differential metal-ion stimulation of cellobiose transport indicate a cellobiose permease, rather than cellobiase plus glucose permease, was responsible for cellobiose transport . Glucose (10-fold molar excess) partially inhibited cellobiose transport . This was enhanced by prior incubation of the cells with glucose, suggesting subsequent metabolism of the glucose was responsible for the inhibition . Compounds interfering with electron transport or maintenance of transmembrane ion gradients inhibited cellobiose uptake, indicating that active transport rather than a phosphoenolpyruvate:phosphotransferase system catalyzed cellobiose transport . Na+, but not Li+, stimulated cellobiose transport.

J Chemother, 1991 Feb, 3 Suppl 2, 12 - 9
Media- and method-dependent variation in MIC values of ceftizoxime for clinical isolates of the Bacteroides fragilis group; Wexler HM et al.; Although ceftizoxime has been used effectively in several clinical trials for infections involving anaerobic bacteria, reports of its in-vitro activity against anaerobes are contradictory and confusing . In an effort to clarify the discrepant reports, we tested 90 strains of Bacteroides fragilis group organisms from patients with perforated or gangrenous appendicitis using eight different susceptibility testing procedures . The minimal inhibitory concentration values were dependent on the technique used; agar dilution values were often four twofold dilutions higher than microbroth dilution values . Agar techniques (including spiral gradient end point) gave values of 36% to 61% susceptible at breakpoint (depending on the technique), while the microbroth dilution techniques gave values of 84% to 92% susceptible . When a 64 micrograms/ml breakpoint for agar dilution testing was used, the methods were more comparable, with the agar methods giving values of 64% to 83% susceptible . The results of the broth disk elution procedure were difficult to read and often did not agree with other values.

Wei Sheng Wu Xue Bao, 1991 Feb, 31(1), 60 - 6
{Purification and immunological behavior of beta-lactamase from Bacteroides fragilis}; Chen J et al.; The beta-lactamase crude extract of Bacteroides fragilis 55 was chromatographed with DEAE-sepharose CL-6B and sephadex G-100 . The partial purified enzyme proteins was further purified by cutting the band on PAGE in which the beta-lactamase was distinguishable from other proteins by our method of fluorescent staining . Using purified preparations to be mixed with liposome-CPS-K, prepared specific antisera against the purified beta-lactamase . Serological reactions were carried out by IgG-ELISA together with western blotting . The results revealed that Bacteroides fragilis beta-lactamase possessed its species-specificity.

Aust Vet J, 1991 Feb, 68(2), 50 - 3
Cross-protective immunity and the serological classification system for Bacteroides nodosus; Stewart DJ et al.; The relationship between the serological classification system for serogroup B and for serogroup H of Bacteroides nodosus and cross-protection between subgroups within these serogroups was examined . Protection against ovine footrot following vaccination was achieved against other subgroup strains provided sufficient cross-reactive antibody was induced by shared pilus antigens . Within serogroup B, better cross-protection against one subgroup was obtained with a pili vaccine than a whole cell vaccine which correlated with higher pilus antibody titres induced by the former . For serogroup H, a lack of cross-protection and serological reactivity between subgroups was demonstrated, which indicates that the prototype strain of subgroup H2 should be designated a new serogroup.

J Chemother, 1991 Feb, 3(1), 6 - 12
Synergistic antibacterial interaction of cefotaxime and desacetylcefotaxime; Molinari G et al.; Cefotaxime (CTX) is metabolized in desacetylcefotaxime (dCTX), a less potent compound which shows, however, a higher stability against selected beta-lactamases produced by Gram-negative organisms . The aim of this study was to verify if the antimicrobial activity of CTX against 260 clinical aerobic and anaerobic pathogens isolated in our institution was enhanced by its metabolic derivative dCTX . The combination of CTX and dCTX, assessed by checkerboard titration, was completely or partially synergistic towards 61% of the 220 aerobic organisms tested and against 68% of the 40 Bacteroides strains analyzed . In addition we have investigated, by the time-kill method, the in-vitro interactions against 50 aerobic strains of CTX and dCTX alone and in combination with netilmicin, a drug often employed in severe infections in combination with beta-lactam agents in order to provide effective killing of resistant nosocomial pathogens . Time-kill studies indicated that 36% of the aerobic nosocomial strains were synergistically inhibited by the combination of CTX/dCTX with netilmicin . These results indicate that dCTX makes an important contribution to the clinical efficacy of CTX.

J Clin Periodontol, 1991 Feb, 18(2), 97 - 100
Short-term bactericidal activity of chlorhexidine gel, stannous fluoride gel and amine fluoride gel tested in periodontal pockets; Oosterwaal PJ et al.; The short-term bactericidal effect of 2% chlorhexidine gel, 4% stannous fluoride gel or amine fluoride gel containing 1.25% fluoride on the subgingival microflora was determined in 40 periodontal pockets of 10 patients . The antimicrobial gels or placebo gel were applied in 5-9 mm deep periodontal pockets 3 times within 10 min . Before and 30 min after the applications, samples were taken of the subgingival microflora for determination of the total number of bacteria as well as the number of black pigmented Bacteroides . Reductions of the total number of bacteria were found in all test groups . The reductions found in the pockets treated with chlorhexidine gel or stannous fluoride gel were significantly greater than the reduction found in the pockets treated with a placebo gel . A significant reduction of black-pigmented Bacteroides was found after treatment with chlorhexidine gel or amine fluoride gel . It is concluded that 2% chlorhexidine gel or 4% stannous fluoride gel has a more than 99% reduction effect on the microflora of periodontal pockets within 30 min after application.

J Clin Periodontol, 1991 Feb, 18(2), 111 - 6
A 4-quadrant comparative study of periodontal treatment using tetracycline-containing drug delivery fibers and scaling; Heijl L et al.; The present study describes results on selected clinical and microbiological parameters obtained by periodontal treatment with ethylene vinyl acetate fibers containing 25% by weight tetracycline hydrochloride placed into the periodontal pocket alone or in combination with scaling . Supragingival plaque control was maintained throughout the study by weekly professional cleaning and 0.2% chlorhexidine mouthrinses . Controls included untreated sites and sites treated by conventional scaling alone in a 4-quadrant split-mouth design . The experiment was conducted on 95 teeth from 10 subjects with periodontal pockets greater than or equal to 6 mm which initially bled on probing . All treatments resulted in changes indicative of effective therapy . Pocket depth was reduced, bleeding on probing decreased and gingival index scores decreased . Parallel to the clinical changes, all treatments reduced total bacterial numbers, % black-pigmented Bacteroides, motile bacteria, non-motile rods, and produced a proportionate increase in cocci . Fiber therapy with or without scaling reduced bacterial counts by approximately 2 orders of magnitude when evaluated at 62 days post-therapy . The combination of fiber therapy with scaling was particularly effective, suggesting a possible synergy between these forms of therapy . The combined therapy eliminated bleeding on probing, and black-pigmented Bacteroides, and produced the greatest mean reduction in pocket depth.

Arch Surg, 1991 Feb, 126(2), 164 - 8
Transient and distant infections alter later intraperitoneal abscess formation; Sawyer RG et al.; Transient nosocomial infections, such as line sepsis and pneumonia, are common in today's critical care patient population . Although generally well treated, the effect of these transient antigen exposures on the immune system is unclear . We have previously shown that prior intraperitoneal inoculation with live bacteria leads to increased numbers of intraperitoneal abscesses . Data presented here demonstrate in a murine model that two immunizations with live Escherichia coli, Bacteroides fragilis, or both, administered systemically via intracardiac injection or at a focal distant site in subcutaneous tissue, significantly increased the number of mixed E coli/B fragilis intraperitoneal abscesses when induced 1 week later . Further, immunization with E coli, either alone or in combination with B fragilis, increased the total number of anaerobes recovered per mouse . Transient or focal sublethal infections can significantly alter an animal's immune response to later infectious insults, particularly the formation of intraperitoneal abscesses.

Gastroenterology, 1991 Feb, 100(2), 513 - 9
Hepatic injury associated with small bowel bacterial overgrowth in rats is prevented by metronidazole and tetracycline; Lichtman SN et al.; Susceptible rat strains develop hepatobiliary injury following the surgical creation of self-filling blind loops that cause small bowel bacterial overgrowth . Luminal bacteria or their cell wall polymers were implicated in the pathogenesis of the lesions because sham-operated rats and rats with self-emptying blind loops, having only slightly increased bacterial counts, did not develop hepatic injury . In this study, antibiotics with different spectra of activities were continuously administered starting 1 day or 22 days after surgery to determine which intestinal flora may be responsible for the development of hepatic injury in rats with small bowel bacterial overgrowth . Four weeks following surgery, Lewis rats with self-filling blind loops receiving no antibiotics had elevated liver histology scores (8.2 +/- 1.3 vs . 0.7 +/- 0.4) and plasma aspartate aminotransferase levels (269 +/- 171 vs . 84 +/- 24) compared with sham-operated rats, P less than 0.001 . Oral gentamicin as well as oral and intraperitoneal polymyxin B, which binds endotoxin, did not prevent hepatic injury in rats with self-filling blind loops . However, oral metronidazole and tetracycline therapy continuously administered beginning 1 day after surgery diminished hepatic injury (histology score 3.0 +/- 1.8, 2.9 +/- 1.1; aspartate aminotransferase 87 +/- 25, 98 +/- 34; respectively P less than 0.001 compared with self-filling blind loops receiving no antibiotics) . Metronidazole also protected Wistar rats that require 12 weeks to develop hepatic injury following experimentally induced small bowel bacterial overgrowth compared with rats with self-filling blind loops that received no antibiotic treatment (histology score 10.4 +/- 1.3 vs . 0.7 +/- 1.1, and aspartate aminotransferase 273 +/- 239 vs . 76 +/- 20, P less than 0.001) . When rats started metronidazole therapy 22 days after self-filling blind loop surgery, elevated aspartate aminotransferase values decreased to normal during the next 77 days and final histology scores were normal . All rats with self-filling blind loops had negative peritoneal, liver, spleen, and blood cultures but approximately 75% of mesenteric lymph node cultures were positive irrespective of antibiotic treatment . Because Bacteroides species have been implicated in causing vitamin B12 and disaccharidase deficiencies in rats with self-filling blind loops, we documented the presence or absence of these organisms from blind loops using selective culture techniques . Metronidazole and tetracycline eliminated Bacteroides sp . from blind loops, but polymyxin B and gentamicin did not.(ABSTRACT TRUNCATED AT 400 WORDS)

Oral Microbiol Immunol, 1991 Feb, 6(1), 34 - 40
DNA probe detection of periodontal pathogens in HIV-associated periodontal lesions; Murray PA et al.; Recent studies have shown that an atypical gingivitis and a rapidly progressive periodontal disease may be early-occurring opportunistic infections associated with human immunodeficiency virus (HIV) infection . This study examined the prevalence of selected periodontal pathogens associated with these HIV-related periodontal lesions . Subgingival plaque samples were obtained from both HIV-seronegative and HIV-seropositive homosexual men and from presumably uninfected heterosexual men . DNA probes were used to detect Actinobacillus actinomycetemcomitans, Bacteroides intermedius, Bacteroides gingivalis, Eikenella corrodens and Wolinella recta in the plaque . The healthy sites in both the seronegative and seropositive homosexual groups showed a greater prevalence of all test bacteria, except for E . corrodens, than did the heterosexual group . HIV-associated periodontitis sites showed a microbial profile qualitatively similar to that of conventional periodontitis, except that B . gingivalis was more prevalent in conventional periodontitis . In contrast, HIV-associated gingivitis sites exhibited a greater prevalence of all bacteria tested than conventional gingivitis sites . In fact, HIV gingivitis generally showed a bacterial profile similar to that of the HIV periodontitis lesions, except that W . recta was significantly more prevalent in HIV periodontitis . These data suggest that the HIV gingivitis lesion is a precursor to HIV periodontitis . Thus, early identification and prophylactic treatment of high-risk individuals may prevent the destruction of periodontal tissues.

Antimicrob Agents Chemother, 1991 Feb, 35(2), 371 - 2
Biochemical properties and purification of metallo-beta-lactamase from Bacteroides fragilis; Bandoh K et al.; The beta-lactamase from Bacteroides fragilis GAI-30144 hydrolyzed imipenem, oxyiminocephalosporins, cephamycins, and penicillins . Enzyme activity was inhibited by EDTA . Zinc completely reversed inactivation of the enzyme by EDTA . The molecular mass of purified enzyme was estimated to be 33,000 daltons.

J Dent, 1991 Feb, 19(1), 46 - 50
Identification, and susceptibility to seven antimicrobial agents, of 61 gram-negative anaerobic rods from periodontal pockets; Abu-Fanas SH et al.; Sixty-one cultures of Gram-negative anaerobic rods were isolated from deep periodontal pockets of patients with rapidly progressive periodontitis . Isolates were speciated as Bacteroides gingivalis (18 isolates), Bacteroides intermedius (8), Bacteroides oris (1), Bacteroides gracilis (17) and Fusobacterium nucleatum (17) . Their susceptibilities, to seven antimicrobial agents, were determined in vitro using a plate dilution technique . Amoxycillin and amoxycillin with clavulanic acid were active against all isolates (MIC less than 1 mg/l) and proved the most effective agents tested . F . nucleatum and B . gracilis showed resistance to erythromycin; F . nucleatum had MIC values ranging from 0.03 mg/l up to 128 mg/l when tested with this, least effective agent . Metronidazole was effective against all isolates except for a few strains of B . gracilis (MIC less than 4 mg/l) . Tetracycline hydrochloride and minocycline were active against all isolates except for a few strains of B . gracilis (MIC less than 2 mg/l with both minocycline and tetracycline hydrochloride) . Penicillin proved less effective than amoxycillin with regard to inhibition of B . gracilis.

J Dent Res, 1991 Feb, 70(2), 82 - 6
Association of proteases of Porphyromonas (Bacteroides) gingivalis with its adhesion to Actinomyces viscosus; Li J et al.; P . gingivalis adheres to A . viscosus on mineral surfaces mimicking teeth . To study whether P . gingivalis proteases contribute to its binding, mutants of P . gingivalis deficient in proteases were compared with their parent strain and a P . gingivalis-type strain for their adherence to A . viscosus on saliva-coated hydroxyapatite by manipulating a radio-isotope binding assay . Adherence of P . gingivalis 2561 to A . viscosus was studied by tests of the effects of incubation temperature and known inhibitors or promoters of proteases . Controls were handled by the assay run in PBS buffer at 22 degrees C . Two mutants deficient in trypsin-like protease were found to be deficient in adherence (% attachment relative to control: 3.2 +/- 0.1% and 11.2 +/- 0.4%), while a collagenase-deficient mutant had an adherence score (51.6 +/- 8.4) closer to that of the parent strain (75.6 +/- 7.2%) . Heating P . gingivalis at 70 degrees C decreased its subsequent adherence at 22 degrees C by 80% . Adherence decreased by 60% when the assay was run at 4 degrees C, but increased by 70% at 37 degrees C . Reducing agents (dithiothreitol, cysteine, and mercaptoethanol) enhanced P . gingivalis adherence by 50 to 60% . Protease inhibitors (BZMD, SBTI, TPCK, TLCK, CMPS, PMSF) decreased adherence by 10 to 50% . Also, Hg2+ and Zn2+ decreased adherence by 30 to 50%, and arginine decreased it by 50% . Most of these effects on P . gingivalis adherence were statistically significant (p less than 0.05) . Analysis of these data suggests that P . gingivalis proteases may contribute to the cohesion of P . gingivalis and A . viscosus.

Am J Vet Res, 1991 Feb, 52(2), 206 - 11
Electron microscopic study of Bacteroides nodosus pili and associated structures; Gradin JL et al.; Surface structures of Bacteroides nodosus were examined by electron microscopy . Collodion film and chrome shadowing were used for maximizing the visualization of B nodosus pili and ring structures . The existence of B nodosus pili in foot rot lesions was confirmed . Contrary to previous reports, it was found that B nodosus pili production can be retained through serial broth transfer under certain conditions . Capsule production by B nodosus was irregular in that it could be either lacking or variable in thickness . A bacteriophage capable of infecting B nodosus also was detected.

Am J Vet Res, 1991 Feb, 52(2), 202 - 5
Diversity of pilin of serologically distinct Bacteroides nodosus; Gradin JL et al.; Pili from 11 distinct serotypes of Bacteroides nodosus were examined for diversity of pilin polypeptide subunits among serotypes and for purity of the pilin preparations . The pilin of all 11 samples was shown to be homogeneous . Mean +/- SD molecular weight of the pilin of 7 serotypes (A198, IV, V, VI, IX, XVII, and XVIII) was 18,500 +/- 100 . The pilin of serotypes I, III, and VIII had molecular weight of 17,600, 19,400, and 19,000, respectively . Serotype XV differed greatly from the other 10 serotypes in that 2 distinct polypeptide bands with molecular weight of approximately 7,800 and 6,200 were detected . We suggest that these 2 low molecular weight bands resulted from proteolytic cleavage of the pilin protein.

Clin Exp Immunol, 1991 Feb, 83(2), 237 - 44
Porphyromonas gingivalis-specific serum IgG and IgA antibodies originate from immunoglobulin-secreting cells in inflamed gingiva; Ogawa T et al.; Patients with adult periodontitis (AP) exhibit elevated serum antibody levels to Porphyromonas (Bacteroides) gingivalis; however, it is not known whether these antibodies originate from plasma cells in the local disease site or from peripheral lymphoid tissues . We studied the isotype and subclass levels and origin of antibodies to P . gingivalis fimbriae, since elevated serum anti-fimbriae responses were seen when compared with sera of healthy controls . IgG anti-fibriae titres were dominant and the subclass response was IgG3 much greater than IgG1 greater than IgG2 much greater than IgG4; however, some IgA anti-fimbriae antibodies were also seen . The IgA subclass fimbriae-specific response was mainly IgA1; however, significant IgA2 anti-fimbrae antibodies were seen . We also assessed numbers of anti-fimbriae antibody producing cells from peripheral blood mononuclear cells (PMBC) and from either healthy or inflamed gingiva of AP subjects . Gingival mononuclear cells (GMC) of AP patients exhibited high numbers of immunoglobulin-producing (spot-forming) cells (SFC) including fimbriae-specific antibody secreting cells in a pattern of IgG greater than IgA greater than greater than greater than IgM . However, low numbers of SFC were seen in GMC from healthy gingiva; further, no anti-fimbriae SFC responses were noted in healthy GMC . Although no fimbriae-specific immunoglobulin-producing cells were seen in PBMC, low numbers of antigen-specific SFC were found in pokeweed mitogen-triggered PBMC from AP subjects . Treatment of AP patients for plaque and surgical removal of inflamed gingiva resulted in significant reductions in serum anti-fimbriae responses . These studies show that AP patients exhibit brisk serum IgG and IgA subclass anti-fimbriae antibodies, whose origin appear to be the plasma cells present in the localized inflamed tissues.

Infect Immun, 1991 Feb, 59(2), 742 - 4
Adherence of Bacteroides fragilis group species; Brook I et al.; The ability of piliated and capsulated Bacteroides fragilis and Bacteroides ovatus to adhere to intestinal cells and mucus was investigated . The adherence of piliated and capsulated strains was at least five times greater than the adherence of their nonpiliated and noncapsulated or capsulated only counterparts . These data illustrate the importance of pili as promoters of adherence of B . fragilis group species to the gastrointestinal mucosa.

Oral Microbiol Immunol, 1991 Feb, 6(1), 6 - 11
The hemagglutinating adhesin HA-Ag2 of Bacteroides gingivalis is distinct from fimbrilin; Mouton C et al.; We carried out a series of immunoblots with antigenic preparations from the periodontal pathogen Bacteroides gingivalis using antisera of restricted specificity for the hemagglutinating adhesin HA-Ag2, and for the major structural subunit of the fimbriae (fimbrilin) . We have been able to show that these 2 antigens are distinct . The fimbrilin subunit had an apparent molecular weight of 42 kDa in all of the bacterial preparations tested . HA-Ag2 occurred as a pair of bands at 43 and 49 kDa in outer membranes prepared as extracellular vesicles, and at 33 and 38 kDa in glass-bead-EDTA extracted antigens and in sheared-cell outer membranes prepared in the presence of EDTA . No HA-Ag2 was found in an enriched fimbrial preparation . The 2 antigens could thus be distinguished on the basis of their behaviour when subjected to different extraction techniques . The lower apparent molecular weight of HA-Ag2 (a pair of bands at 33 and 38 kDa) was invariably associated with the presence of EDTA in the buffers used to prepare the extracts, and the effect could be partially prevented by adding MgCl2 to the extraction buffer . The difference in apparent molecular weight of HA-Ag2 in the different extracts can thus be attributed either to an EDTA-sensitive tertiary conformation of its component polypeptides, or to an EDTA-sensitive linkage of each of these polypeptides to an unknown component of approximately 10 kDa.

Biochem Biophys Res Commun, 1991 Jan 31, 174(2), 625 - 30
Salivary histatin as an inhibitor of a protease produced by the oral bacterium Bacteroides gingivalis; Nishikata M et al.; We examined the effect of histatin 5 from human parotid saliva on various proteases . Histatin 5 strongly inhibited a trypsin-like protease produced by Bacteroides gingivalis with an IC50 value of 55 nM . Clostripain was also inhibited (IC50 = 800 nM) . Activities of other proteases were not affected significantly . Because B . gingivalis is a suspected periodontal pathogen and its proteolytic enzymes have been considered to be associated with periodontal tissue destruction, it is suggested that salivary histatins play a role as a preventive against periodontal disease.

FEMS Microbiol Lett, 1991 Jan 15, 61(2-3), 289 - 93
Formation of glycoprotein degrading enzymes by Bacteroides fragilis; Macfarlane GT et al.; Bacteroides fragilis NCDO 2217 produced a wide range of cell-associated hydrolytic enzymes (neuraminidase, alpha-fucosidase, alpha-N-acetylgalactosaminidase, beta-galactosidase, beta-N-acetylglucosaminidase) that could potentially degrade the carbohydrate moieties of mucin, a complex glycoprotein . The type of substrate used for growth markedly influenced their formation in batch cultures . Synthesis of neuraminidase, alpha-fucosidase, alpha-N-acetylgalactosaminidase and to a lesser extent, beta-N-acetylglucosaminidase, was inversely related to growth rate in continuous cultures (D = 0.03 h-1-0.23 h-1) in which porcine gastric mucin provided the sole source of carbon and nitrogen.

Free Radic Res Commun, 1991, 12-13 Pt 1, 313 - 8
In vivo metal substitution in Bacteroides fragilis superoxide dismutase; Chen Y et al.; Bacteroides fragilis, an obligate anaerobe, synthesizes an azide-inhibitable iron-containing superoxide dismutase when grown in complex medium . Cells grown anaerobically in complex media containing desferrioxamine (Desferal, Ciba-Geigy) and graded concentrations of Mn synthesize the azide-resistant manganese-containing SOD . The fraction of MnSOD activity in dialyzed cell extracts increased progressively as the Mn concentration in the medium increased . The fraction of MnSOD activity also increased in extracts of cells grown in the medium with 1 mM Mn but with graded concentrations of desferrioxamine (0-10 micromolar) . The SOD activity in the cells grown under the various conditions varied but not in a causal relationship with either Mn or desferrioxamine concentration . Electrophoresis revealed that the SOD activity in cells grown in the absence or presence of 1 mM Mn migrated with the same relative mobility and exhibited identical activity patterns when examined separately or as a mixture . These data are consistent with substitution of Mn for Fe in the B . fragilis apoprotein under anaerobic conditions and support the model of a single protein binding either Fe or Mn.

Microbiologica, 1991 Jan, 14(1), 71 - 5
Demonstration by confocal laserscanning microscopy of invasive potential with Bacteroides fragilis; Goldner M et al.; The confocal laserscanning microscopy (CLSM) system provides a stereoscopic view of an object . By this system the penetration of B . fragilis into HeLa cells was observed . The intensity of contact is highlighted with time . The CLSM system consolidates the recently described fluorescence technique to test invasive potential . This work purports that certain gram-negative anaerobes should be considered for invasiveness.

J Clin Periodontol, 1991 Jan, 18(1), 1 - 15
Specific antibody responses to subgingival plaque bacteria as aids to the diagnosis and prognosis of destructive periodontitis; Wilton JM et al.; We have reviewed the recent literature on the humoral immune responses to a variety of subgingival plaque bacterial species in patients with destructive periodontal diseases . We do not feel that the information presently available on the specific antibody responses to proposed pathogens such as Bacteroides gingivalis and Actinobacillus actinomycetemcomitans allows antibody responses to be diagnostic . All control subjects without periodontal destruction have antibodies to candidate pathogens but the generally higher levels in patients are not sufficiently elevated to be diagnostic . Nor can they be used to predict the initiation of disease or the onset of new episodes of destruction where disease had previously occurred . Successful treatment of patients may lead to lower levels of antibodies to some organisms, including possible pathogens, and thus support a given species in the aetiopathogenesis of disease . It appears that unsuccessful treatment may be accompanied by continuing high antibody levels to some organisms and further studies may enable this observation to be used to monitor therapy . There is some evidence from serological studies that each destructive episode may be induced by a different bacterial species or consortium . The start of studies using single antigens and the techniques of molecular biology will provide not only antibody-based diagnostic methods but also allow us to determine which bacterial antigens are virulence factors and thus the role of the antibody responses, whether protective or damaging, in the periodontal diseases.

Pharmacotherapy, 1991, 11(2 ( Pt 2)), 51S - 55S
Newer beta-lactam agents and the Bacteroides fragilis group; Cuchural GJ Jr; A continuing nationwide susceptibility survey of the Bacteroides fragilis group, begun in 1981, is being conducted at the New England Medical Center . Review of susceptibility testing in years 1986 through 1988 is reported here . Totals of 557 strains in 1986, 506 in 1987, and 534 in 1988 were obtained from seven centers in the United States . The most active beta-lactam drugs were beta-lactamase-inhibitor combinations ticarcillin-clavulanic acid, ampicillin-sulbactam, cefoperazone-sulbactam and the carbapenem imipenem . These drugs had virtually no resistance detected . Their rank order of activity was imipenem, ampicillin-sulbactam, ticarcillin-clavulanic acid, and cefoperazone-sulbactam, all with activity levels greater than cefoxitin or piperacillin, which, in turn, had activity levels greater than moxalactam, ceftizoxime, cefotetan, cefotaxime, cefoperazone, and ceftazidime . No metronidazole- or chloramphenicol-resistant isolates were found . Clindamycin resistance averaged 6% over the 3 years of testing . Ticarcillin-clavulanic acid, ampicillin-sulbactam, imipenem, and the non-beta-lactam drugs displayed uniform excellent activity against the five species of the B . fragilis group tested . The other beta-lactams displayed significant variability of activity among the various species.

Appl Environ Microbiol, 1991 Jan, 57(1), 277 - 82
Introduction of the Bacteroides ruminicola xylanase gene into the Bacteroides thetaiotaomicron chromosome for production of xylanase activity; Whitehead TR et al.; The xylanase gene from the ruminal bacterium Bacteroides ruminicola 23 is highly expressed in colonic Bacteroides species when carried on plasmid pVAL-RX . In order to stabilize xylanase expression in the absence of antibiotic selection, the xylanase gene was introduced into the chromosome of Bacteroides thetaiotaomicron 5482 by using suicide vector pVAL-7 . Xylanase activity in the resulting strain, B . thetaiotaomicron BTX, was about 30% of that observed in B . thetaiotaomicron 5482 containing the xylanase gene on pVAL-RX . The data obtained from continuous culture experiments using antibiotic-free medium showed that expression of xylanase activity in strain BTX was extremely stable, with no demonstrated loss of the inserted xylanase gene over 60 generations, with dilution rates from 0.42 to 0.03 h-1 . In contrast, the plasmid-borne xylanase gene was almost completely lost by 60 generations in the absence of antibiotic selection . Incubation of strain BTX with oatspelt xylan resulted in the degradation of more than 40% of the xylan to soluble xylooligomers . The stability of xylanase expression in B . thetaiotaomicron BTX suggests that this microorganism might be suitable for introduction into the rumen and increased xylan degradation.

Appl Environ Microbiol, 1991 Jan, 57(1), 1 - 6
Co-utilization of polymerized carbon sources by Bacteroides ovatus grown in a two-stage continuous culture system; MacFarlane GT et al.; Bacteroides ovatus NCTC 11153 was grown in a two-stage continuous culture system at various growth rates (vessel 1, D = 0.06 to 0.19 h-1; vessel 2, D = 0.03 to 0.09 h-1) on media containing mixtures of starch and arabinogalactan as carbon sources . The cell-associated enzyme activities needed to hydrolyze both substrates (amylase, arabinogalactanase, alpha-glucosidase, beta-galactosidase, and alpha-arabinofuranosidase) were variously influenced by growth rate and polysaccharide availability but were detected under all growth conditions tested . Measurements of residual carbohydrate in spent culture media showed that both polysaccharides were co-utilized during growth under putative C-limited conditions . The arabinogalactan was partly depolymerized in N-limited chemostats, and significant amounts of arabinose- and galactose-containing oligosaccharides accumulated in the cultures, indicating that starch was being preferentially utilized . Acetate, propionate, and succinate were the major fermentation products formed by C-limited bacteria, but under N limitation, lactate was also produced . Molar ratios of succinate increased concomitantly with the dilution rate in C-limited chemostats, whereas molar ratios of propionate decreased . During N-limited growth, however, decarboxylation of succinate to propionate was relatively independent of growth rate . Cell viability was higher in C-limited cultures compared with those grown under N limitation and was greatest at high dilution rates, irrespective of nutrient limitation.

Zhonghua Kou Qiang Yi Xue Za Zhi, 1991 Jan, 26(1), 15 - 7, 61
{Determination of serum antibody against Bacteroides gingivalis from rapidly progressive periodontitis and juvenile periodontitis patients}; Cao C; Bacteroides gingivitis (Bg) is one of the major pathogens associated with periodontitis . This is the first report in China on serum antibody level against Bg from patients with rapidly progressive periodontitis (RPP) and juvenile periodontitis (JP) using ELISA method . 21 RPP patients, 20 JP patients and 30 healthy subjects (H) were involved in this study . The results showed that the ratio of positive antibody response was 100% in RPP, 80% in JP and 30% in control group . The antibody response in both RPP and JP groups were significantly greater than that in healthy group (P less than 0.001) . The difference between RPP and JP groups were also statistically significant (P less than 0.05).

Vet Microbiol, 1991 Jan, 26(1-2), 151 - 60
Characterisation of virulent and benign strains of Bacteroides nodosus; Depiazzi LJ et al.; The extracellular proteases of 395 isolates of B . nodosus from ovine, bovine and caprine foot lesions were classified as either thermostable or thermolabile . Stable protease was associated with one and unstable protease with four distinctive isoenzyme patterns, each pattern differentiated by the relative mobility of paired isoenzymes . Pathogenicity tests on 64 isolates showed a correlation between the production of stable protease and the production of virulent ovine footrot lesions . The mean values for total protease activity, twitching motility and colony diameter were significantly higher for virulent compared to benign isolates, but the range of values overlapped . SDS-PAGE whole-cell electrophoretic profiles of virulent isolates were similar to the profiles of some benign isolates.

Rev Infect Dis, 1991 Jan-Feb, 13(1), 12 - 8
Epidemiology, antimicrobial susceptibility, pathogenicity, and significance of Bacteroides fragilis group organisms isolated at Los Angeles County-University of Southern California Medical Center; Appleman MD et al.; The epidemiology of species of the Bacteroides fragilis groups isolated at Los Angeles County-University of Southern California Medical Center was examined . In addition, frequency of resistance to six beta-lactam antibiotics (cefmetazole, cefotetan, ceftizoxime, imipenem, penicillin, and cefoxitin) and to clindamycin, chloramphenicol, and metronidazole was determined for each species . While B . fragilis was most commonly isolated, the other species of the B . fragilis group accounted for half of the isolates . Seven percent of 1,128 patients with infections due to species of the B . fragilis group were bacteremic . A review of bacteremic cases indicated that non-fragilis species were highly pathogenic . Resistance to clindamycin ranged from 8% to 22% among species and was most common among isolates of Bacteroides distasonis and Bacteroides thetaiotaomicron . Significant differences in antimicrobial activity were noted among the agents tested . Only imipenem, chloramphenicol, and metronidazole were predictably effective against non-fragilis species of the B . fragilis group . Prompt identification of species and susceptibility testing of clinical isolates of this group are needed if a newer beta-lactam agent or clindamycin is to be used for initial therapy.

Clin Exp Immunol, 1991 Jan, 83(1), 108 - 11
T cell proliferative responses to molecular fractions of periodontopathic bacteria; Ivanyi L et al.; Soluble antigenic preparations of Veillonella parvula and Bacteroides gingivalis were separated by SDS-PAGE and used after electroblotting and solubilization for in vitro lymphocyte stimulation in 13 patients with severe periodontitis and 12 controls . The cellular responses of controls and patients to V . parvula antigens were represented by four main proliferation-inducing fractions with 74-66, 52-46, 22-19 and 12 kD mol . wt . These fractions induced slightly enhanced DNA synthesis in lymphocytes from eight patients who failed to respond to whole antigenic extract . Lymphocyte samples from Veillonella whole extract unresponsive patients were also examined for in vitro proliferation by B . gingivalis fractions . Almost all stimulatory activities could be classified into five regions of 84-74, 35-31, 28-25, 17-15 and 12 kD.

J Bacteriol, 1991 Jan, 173(2), 495 - 504
Specific cell components of Bacteroides gingivalis mediate binding and degradation of human fibrinogen; Lantz MS et al.; Bacteroides (Porphyromonas) gingivalis, which has been implicated as an etiologic agent in human periodontal diseases, has been shown to bind and degrade human fibrinogen . B . gingivalis strains bind fibrinogen reversibly and with high affinity and bind to a specific region of the fibrinogen molecule that appears to be located between the D and E domains (M . S . Lantz, R . D . Allen, P . Bounelis, L . M . Switalski, and M . Hook, J . Bacteriol . 172:716-726, 1990) . We now report that human fibrinogen is bound and then degraded by specific B . gingivalis components that appear to be localized at the cell surface . Fibrinogen binding to bacterial cells occurred at 4, 22, and 37 degrees C . A functional fibrinogen-binding component (Mr, 150,000) was identified when sodium dodecyl sulfate-solubilized bacteria were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and probed with 125I-fibrinogen . Fibrinogen degradation did not occur at 4 degrees C but did occur at 22 and 37 degrees C . When bacteria and iodinated fibrinogen were incubated at 37 degrees C, two major fibrinogen fragments (Mr, 97,000 and 50,000) accumulated in incubation mixture supernatant fractions . Two major fibrinogen-degrading components (Mr, 120,000 and 150,000) have been identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in substrate-containing gels . Fibrinogen degradation by the Mr-120,000 and -150,000 proteases was enhanced by reducing agents, completely inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone, and partially inhibited by n-ethyl maleimide, suggesting that these enzymes are thiol-dependent proteases with trypsinlike substrate specificity . The fibrinogen-binding component could be separated from the fibrinogen-degrading components by selective solubilization of bacteria in sodium deoxycholate.

Infect Immun, 1991 Jan, 59(1), 383 - 9
Porphyromonas (Bacteroides) gingivalis fimbrillin: size, amino-terminal sequence, and antigenic heterogeneity; Lee JY et al.; Bacterial fimbriae mediate cell adhesion and are important in colonization . Fimbrial proteins from strains of Porphyromonas (Bacteroides) gingivalis isolated from different individuals were compared for their size, amino-terminal sequence, and antigenic diversity . Two major protein components of the crude fimbrial preparations differed in apparent molecular mass, ranging from 41 to 49 kDa for the fimbrillin monomer and from 61 to 78 kDa for the other major protein . The amino-terminal sequence of the antigenically related group of proteins of the fimbrillin monomer in the 41- to 49-kDa range showed significant homology; however, minor sequence heterogeneity was observed, mainly in residues 4 to 6 . One of the observed amino-terminal sequences, AFGVGDDESKVAKLTVMVYNG, resembled the deduced sequence of P . gingivalis 381 (D.P . Dickinson, M . K . Kubiniec, F . Yoshimura, and R.J . Genco, J . Bacteriol . 170:1658-1665, 1988) . Fimbriae from all the strains of P . gingivalis showing this sequence contained a fimbrillin monomer of 43 kDa and showed a strong reaction with both polyclonal and monoclonal antibodies directed to the fimbriae from P . gingivalis 2561 (381) . Fimbriae from strains showing amino-terminal sequence variations in residues 4 to 6 (i.e., substitution of VGD with either E or NAG) were more diverse in their molecular sizes . Most of these variant fimbriae showed weak reactions with the polyclonal antibodies and no reaction with the monoclonal antibodies induced to the fimbriae of strain 2561 . No correlation could be established between the molecular size and immunological reactivity of the fimbrillin monomer of P . gingivalis strains . Strains 9-14K-1 and HG 564 not only showed markedly different sequences from the other three amino-terminal sequences but also did not react with either polyclonal or monoclonal antibodies to the fimbriae of strain 2561 . Strains W50, W83, and AJW 5 failed to show any immunological reactivity with the antibodies to fimbrillin or fimbriae of strain 2561 . Fimbriae from different strains revealed different immunologic reactions with rabbit antisera to each of the synthetic peptides of residues 59-78 (peptide I), 79-100 (peptide J), and 91-108 (peptide E) of strain 381 . These results suggest that P . gingivalis fimbrillin subunits have size, sequence, and antigenic heterogeneity among the strains and that these differences may be important in the function and immune reactivities of the fimbriae.

J Mal Vasc, 1991, 16(3), 243 - 8
{Venous thrombosis in gastroenterology}; Valla D; Venous thrombosis involving the digestive tract affects the suprahepatic veins and the terminal part of the inferior vena cava, the portal vein and its roots . The etiology and diagnosis of this condition have made considerable progress . A thrombogenic disease can now be recognized in 90% of cases of involvement of the suprahepatic veins, and 75% of portal involvements . The most frequent causes are primary myeloproliferative syndromes, paroxysmal nocturnal hemoglobinuria, hereditary deficiency in coagulation proteins and circulating anticoagulants . The cause of involvement of the portal vein also include insults during biliary surgery and abdominal infections, particularly those caused by Bacteroides fragilis . Mechanical involvement due to compression finally plays a minor role in the etiology . Noninvasive techniques of diagnosis are now available, including ultrasound, computed tomography and magnetic resonance imaging . The expression of obstruction of the suprahepatic veins predominantly consists in ascites and hepatomegaly . Thrombosis of the portal vein preserving the mesenteric arches usually remains asymptomatic until the intrahepatic block is revealed by a digestive hemorrhage caused by portal hypertension . Isolate involvement of the splenic vein exceptionally causes the rupture of gastric or esophageal collateral veins . The treatment should combine the prevention of further thromboses by anticoagulants and the specific treatment of the venous obstruction . In case of suprahepatic obstruction, there are several methods of restoring a canal of drainage for hepatic blood . Their indications depend on the patency of the inferior vena cava and of the portal vein . In case of portal obstruction, portal-systemic bypass is feasible only if one of the major roots of the portal vein still is patent.(ABSTRACT TRUNCATED AT 250 WORDS)

J Hyg Epidemiol Microbiol Immunol, 1991, 35(2), 189 - 97
Comparison of the activity of imipenem and beta-lactams combined with sulbactam and clavulanic acid in beta-lactamase-producing strains of Bacteroides fragilis; Martin MA et al.; We compared the "in vitro" activity of imipenem with 14 beta-lactams, both alone and in combination with clavulanic acid, and sulbactam against 110 beta-lactamase-producing strains of Bacteroides fragilis . The following antibiotics were tested: amoxycillin, penicillin, mezlocillin, piperacillin, cephalothin, cephazolin, cefamandole, cefmetazole, cefonicid, cefoxitin, cefotaxime, ceftazidime, ceftizoxime, and ceftriaxone . In all cases, except those of cefoxitin and cefmetazole, these combinations showed a statistically significant increase in beta-lactam activity, which was, however, never higher than that of imipenem, the antibiotic which performed best against Bacteroides fragilis.

Int Endod J, 1991 Jan, 24(1), 8 - 14
Class II antigen expressing cells in experimentally induced pulpitis; Bergenholtz G et al.; This study reports on the occurrence of class II antigen expressing cells in inflammatory lesions experimentally induced in the rat incisor pulp . Concanavalin A and lipopolysaccharide of Bacteroides gingivalis were applied to the exposed pulp following a preparation through alveolar bone and dental tissues in the midpart of the root . In a set of control teeth, pulpal exposures were capped with Cavit without the placement of antigenic material . Animals were killed after 3, 12, 24, 48 or 96 hours . Pulp tissue specimens were subjected to immunohistochemical analysis utilizing a monoclonal mouse anti-rat class II antigen antibody . Semi-quantitative assessment of positively stained cells was carried out under the light microscope . Significantly more class II antigen expressing cells were identified in the challenged pulps than in the controls at all experimental periods . The increase in cells peaked at 48 hours to taper off at the subsequent 96-hour observation . The rapid and intense influx of class II antigen expressing cells suggests that these cells are associated with the initial defence of the dental pulp.

Arch Oral Biol, 1991, 36(5), 341 - 6
Inhibition of bovine gingival laminin receptor by bacterial lipopolysaccharide; Slomiany BL et al.; A laminin receptor was isolated from bovine gingival epithelial-cell membrane . After solubilization with octylglucoside, the receptor was subjected to affinity chromatography on laminin-coupled Sepharose and eluted with cation-free EDTA buffer yielding on SDS-PAGE a 67 kDa protein band . After radioiodination, the protein was incorporated into liposomes which displayed specific affinity towards laminin-coated surfaces, as well as to tooth cementum . The binding of receptor protein to cementum was inhibited by lipopolysaccharide from Bacteroides gingivalis . Preincubation of cementum with the lipopolysaccharide decreased the binding of the liposomal laminin-receptor preparation by 35.8%, while a 59.2% decrease in binding occurred when the lipopolysaccharide was preincubated with the receptor, suggesting that the lipopolysaccharide interfered with the laminin binding site on the receptor . The results demonstrate the existence of a specific gingival cell-surface laminin receptor, show that it is capable of binding to cementum, and provide evidence for the disruption of this process by bacterial lipopolysaccharide . This mechanism may account for the loss of gingival attachment in the pathogenesis of periodontal disease.

Nor Tannlaegeforen Tid, 1991 Jan, 101(2), 50 - 2
{Tetracycline resistance in oral microorganisms in patients with periodontal disease}; Olsvik B; Several longitudinal studies have shown that periodontal treatment consisting of surgical and/or nonsurgical debridement of the teeth often is sufficient to prevent continued attachment loss when the patients' oral hygiene measures are good . Nevertheless, some patients will, in spite of excellent oral hygiene measures, continue to show attachment loss . The treatment of these patients has mainly been empirical, and the clinicians have used different kinds of antibiotics for different time intervals to eliminate proposed periodontal pathogens . The preferred antibiotic has been tetracycline . Most bacteria associated with destructive periodontal disease will normally be susceptible to tetracycline at the levels achieved in the gingival crevicular fluid after systemic administration of the antibiotic . Some patients have a microbial flora that will not change enough or be inhibited by these substances . The reason for this may in many cases be the development of antimicrobial resistance . Today 14 genotypes of tetracycline resistance have been found . The resistance is one of three types: active secretion, protection of the ribosomes by proteins and an active breakdown of tetracycline . The third type has recently been discovered as a cryptic gene in the microorganism Bacteroides fragilis . This gene is only expressed after transfer to Eschericia coli . Active breakdown of tetracycline does normally not occur in nature and the global level of the drug is increasing since tetracycline is the second most used antibiotic in the world today . It is therefore of interest to identify tetracycline resistance determinants in the oral cavity and to compare these with tetracycline resistance genes from other sources of human, animal and environmental origin.

J Bacteriol, 1991 Jan, 173(1), 176 - 83
Evidence that a novel tetracycline resistance gene found on two Bacteroides transposons encodes an NADP-requiring oxidoreductase; Speer BS et al.; Two transposons, Tn4351 and Tn4400, which were originally isolated from the obligate anaerobe Bacteroides fragilis, carry a tetracycline resistance (Tcr) gene that confers resistance only on aerobically grown Escherichia coli . This aerobic Tcr gene, designated tetX, has been shown previously to act by chemically modifying tetracycline in a reaction that appears to require oxygen . We have now obtained the DNA sequence of tetX and 0.6 kb of its upstream region from Tn4400 . Analysis of the DNA sequence of tetX revealed that this gene encoded a 43.7-kDa protein . The deduced amino acid sequence of the amino terminus of the protein had homology with a number of enzymes, all of which had in common a requirement for NAD(P) . In an earlier study, we had observed that disrupted cells, unlike intact cells, could not carry out the alteration of tetracycline . We have now shown that if NADPH (1 mM) is added to the disrupted cell preparation, alteration of tetracycline occurs . Thus, TetX appears to be an NADP-requiring oxidoreductase . Tn4400 conferred a fivefold-lower level of tetracycline resistance than Tn4351 . This finding appears to be due to a lower level of expression of the tetX on Tn4400, because the activity of a tetX-lacZ fusion from Tn4400 was 10-fold lower than that of the same fusion from Tn4351 . A comparison of the sequence of the tetX region on Tn4351 with that on Tn4400 showed that the only difference between the upstream regions of the two transposons was a 4-base change 350 bp upstream of the start of the tetX coding region . The 4-base change difference creates a good consensus -35 region on Tn4351 that is not present on Tn4400 and could be creating an extra promoter.

Cesk Epidemiol Mikrobiol Imunol, 1991 Jan, 40(1), 56 - 9
{Resistance of intestinal strains of Bacteroides to antibiotics and chemotherapeutic agents}; Hudac A et al.; Antibacterial therapy of anaerobic infections usually involves chemotherapy . The basis of therapy is assessment of the minimal inhibitory concentration (MIC) of antibiotic or chemotherapeutic agents needed to eliminate the suspected causal agents of infection . The authors assessed MIC of 9 selected antibiotics and chemotherapeutic agents (metronidazole, chloramphenicol, clindamycin, azlocillin, mezlocillin, cephoxitin, oxytetracycline, lincomycin, erythromycin) by the dilution method in blood agar in 157 strains of the most important types of the genus Bacteroides which were isolated in 1985-1989 from different clinical materials in Bratislava and in Halle (GDR) . All tested strains were sensitive to metronidazole and chloramphenicol . Resistance to clindamycin was very rare . Strains resistant to azlocillin, mezlocillin and cephotoxin were more frequent . A high resistance to lincomycin, oxytetracycline and erythromycin was found . Difference in sensitivity of strains from the CSSR and GDR were slight . Similarly results of the present work differed little from those of previous work.

J Periodontal Res, 1991 Jan, 26(1), 33 - 41
Topical chemotherapy in human periodontitis using a new controlled-release insert containing ofloxacin . I . Microbiological observation; Kimura S et al.; The recognition that destructive periodontal diseases may be caused by specific microorganisms in periodontal pockets has led to an increased interest in and usage of antimicrobial agents in periodontal therapy . Recently, a new controlled-release insert containing ofloxacin, a synthetic antibiotic, has been developed . In this study, the controlled-release insert (PT-01) was microbiologically evaluated in combination with or without subgingival mechanical debridement . PT-01 was applied in the periodontal pockets of 27 patients with chronic periodontitis . Three sites with a deep probing pocket depth (greater than or equal to 5 mm) were randomly selected in different quadrants of each patient, and were assigned into three groups, i.e., PT-01 applied (T), placebo applied (P) and control sites (C) . Periodontal treatments consisted of supragingival scaling with oral hygiene instruction for the first 2 weeks followed by root planing and subgingival scaling PT-01 was applied weekly on day 0 to 35, and the subgingival plaque samples from each site were collected on d 0, 14, 21 and 42 . The dynamics of the subgingival microflora was investigated by dark field microscopy and by anaerobic and aerobic cultivation . In the supragingival scaling period, significant reduction in percentages of spirochetes and motile rods and significant increase of the percentage of coccoid cells were observed only at T sites . In addition, the total viable counts of bacteria, black-pigmented Bacteroides and Fusobacterium species were significantly reduced at T sites . After mechanical subgingival debridement, significant shifts in the proportion and reduction of the viable counts in the subgingival microflora were found at all sites.(ABSTRACT TRUNCATED AT 250 WORDS)

J Periodontal Res, 1991 Jan, 26(1), 24 - 32
Gingival crevicular fluid elastase-inhibitor complex: correlation with clinical indices and subgingival flora; Zafiropoulos GG et al.; This investigation analyzed, in a cross-sectional study, the possible relationship between gingival crevicular fluid (GCF) elastase-like protease (ELP) levels and the periodontal clinical parameters or the presence of specific bacteria in subgingival plaque . A total of 388 periodontal sites from 8 adult periodontitis patients were examined for plaque index (PII), gingival index (GI), pocket depth (PD) and alveolar bone loss (ABL) . GCF ELP levels were determined as ELP alpha-1 protease inhibitor (ELP-alpha 1-PI) complex levels with a commercially available ELISA . Subgingival plaque samples were tested for the presence of Bacteroides gingivalis, B . intermedius and Actinobacillus actinomycetemcomitans by indirect immunofluorescence (IF) microscopy . GCF ELP-alpha 1-PI levels were then correlated with clinical periodontal indices and proportions of IF-positive bacteria per site . Statistically significant positive correlations were found between GCF ELP-alpha 1-PI concentrations and subgingival Bacteroides proportions . When the sites examined were analyzed depending on the level of each clinical parameter, the levels of these correlations changed . A . actinomycetemcomitans correlated highly (r = 0.716) with ABL for sites with low GI score . The correlations between GCF ELP-alpha 1-PI and B . gingivalis (r = 0.642) or B . intermedius (r = 0.774) were the highest for ABL less than or equal to 20% and PD less than or equal to 3 mm, respectively . The strong association between GCF ELP-alpha 1-PI concentrations and subgingival bacteria previously associated with advancing periodontitis indicates that measurement of GCF ELP-alpha 1-PI concentrations may be useful in the evaluation of periodontal sites, especially those with very little or no tissue destruction.

Dtsch Stomatol, 1991, 41(12), 460 - 2
{First results with a microbiological quick diagnostic procedure in periodontitis}; Kleber BM; We tested a new diagnostic procedure for the characterization of subgingival plaque in 119 subjects suffering from adult periodontitis . The method can be characterized as a hydrolysis of BANA (N-benzoyl-DL-arginine-beta-naphthylamide) by peptidases of Porphyromonas gingivalis, Bacteroides forsythus and Treponema denticola . The result of a positive will be a more or less blue coloured test paper representing the amount of these three peridontal pathogens into the subgingival plaque . After the periodontal initial therapy the frequency of the positive colour reaction was significantly reduced . A correlation between the colour reaction and the clinical signs of periodontitis as well as the morphological characterization of subgingival plaque by darkfield microscopy could not been found . The new method for the characterization subgingival plaque seems to be useful for the judgement of a successful periodontal therapy at single sites.

J Clin Dent, 1991, 3(1), 1 - 5
Antimicrobial activity of flurbiprofen and ibuprofen in vitro against six common periodontal pathogens; Hersh EV et al.; Nonsteroidal antiinflammatory drugs (NSAIDs) such as flurbiprofen and ibuprofen, have been shown to inhibit the inflammation and alveolar bone loss associated with chronic destructive periodontal disease . However, the direct effect of NSAIDs on the gingival crevice microflora has not been studied . The purpose of this investigation was to evaluate the antimicrobial activity of ibuprofen and flurbiprofen in vitro on six commonly isolated periodontal pathogens . The bacterial strains evaluated were Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, Bacteroides intermedius, Eikenella corrodens, Fusobacterium nucleatum and Wolinella recta . Pure cultures of these organisms were inoculated into broth, allowed to grow and inoculated again into sheep blood agar plates . For preliminary dose-response studies, antibiotic sensitivity blank disks loaded with 10 microliters of flurbiprofen 250 micrograms, 50 micrograms and 5 micrograms, or ibuprofen 500 micrograms, 50 micrograms and 5 micrograms were placed on the seeded agar plates . Clindamycin 2 micrograms disks were used as positive controls and discs loaded with only drug vehicle served as negative controls . In an attempt to estimate the minimal inhibitory concentrations of these NSAIDs on specific microorganisms, additional experiments employing intermediate drug dosages were also performed . Clindamycin produced large zones of inhibition for all bacterial strains except for Eikenella corrodens which is known to be resistant to the antibiotic and Actinobacillus actinomycetemcomitans which appeared to be only moderately sensitive to the antibiotic . Zones of inhibition were not produced by any of the negative control disks or by the 5 micrograms or 50 micrograms doses of either NSAID.(ABSTRACT TRUNCATED AT 250 WORDS)

Infection, 1991, 19 Suppl 6, S345 - 50
Calculated empiric antimicrobial therapy for mixed surgical infections; Wittmann DH et al.; In acute life-threatening surgical infections requiring immediate institution of antimicrobial therapy before bacteriological results are available, antibiotic treatment must be empiric . For best efficacy a more sophisticated form of empiric therapy is offered, termed calculated antibiotic therapy (CAT) . Calculated antibiotic therapy requires consideration of a) typical bacterial spectrum; b) bacterial pathogenicity and synergism; c) antibacterial concentrations at the site of infection; d) toxicity and adverse effects; e) interaction with immune response; and f) results of properly conducted trials . Intraabdominal infections are used as an example here to assess the efficacy of clinically used cephalosporins and penicillins for determination of calculated antibiotic therapy . CAT identifies Escherichia coli and Bacteroides fragilis as the most important pathogens for intraabdominal infections and determines the most effective antibiotics at the tissue breakpoint, which is defined as the minimal concentration maintained for more than 90% of the dosage interval period at the infected tissues . At the tissue breakpoint calculated antibiotic therapy identifies cefotaxime-generation cephalosporins to be fully (100%) active against the most important aerobic pathogen E . coli and metronidazole as fully active against the important obligate anaerobe B . fragilis . Calculated antibiotic therapy becomes relatively important, since impeccably controlled clinical therapeutic trials as a foundation for therapy are rarely published.

Shoni Shikagaku Zasshi, 1991, 29(1), 72 - 85
{Subgingival microflora in children of early childhood, school age and circumpuberty . The proportion and frequency of gram-negative bacteria in periodontally healthy and gingivitis groups}; Nakagawa S et al.; The present study characterized the microbial profiles of the gingival sulci in children . Subgingival samples from 36 gingivitis lesions of 18 patients and 36 sites in 18 healthy persons were examined . The tested individuals were divided into three stages according to physiological maturation i.e . early childhood, school age, circumpuberty . Puberty was confirmed through examination of wrist radiographs . Using continuous anaerobic techniques, samples were dispersed, diluted and then inoculated on selective and nonselective media and cultured under the condition appropriate gaseous phase respectively . Isolates were identified microbiologically and counted . All values were evaluated statistically . The samples were simultaneously examined by dark-field microscopy . Changes in the proportions and the frequency of periodontophathic bacteria were distinct in different stages of physiological maturation . Black-pigmented Bacteroides species were commonly found in gingivitis lesions . Bacteroides intermedius was frequently detected in the subgingival samples from children with gingivitis . In all stages, the proportion of black-pigmented Bacteroides and B . intermedius in the gingivitis groups were found to be significantly higher than that of the healthy groups . Statistical analysis revealed that levels of B . intermedius increased in circumpuberty stage compared with the 2 younger stages . Black-pigmented Bacteroides and B . intermedius were closely related to GI, PlI in 3 stages . Bacteroides gingivalis was found only in two gingivitis sites of a circumpubertal child with gingivitis . Actinobacillus actinomycetemcomitans was detected in 4 out of 12 sites in the school age group, and in 6 out of 12 sites in the circumpuberty group with gingivitis respectively . In the circumpuberty group, the proportion of A . actinomycetemcomitans in the gingivitis group was significantly higher than that of the healthy group, and A . actinomycetemcomitans was closely related to GI, PlI, CI, PPD . Eikenella corrodens was found to be associated with gingivitis in the school age and circumpuberty groups . No correlation was found in the detection of Fusobacterium nucleatum in 3 stages . Microscopic examination showed that the proportion of rods, fusiforms, filaments, motile rods, spirochetes in the gingivitis groups was significantly higher than that of the healthy groups, while the proportion of cocci in gingivitis groups was significantly lower than that of the healthy groups in 3 stages . Spirochetes were closely related to GI, PlI, PPD in all stages.

Microbios, 1991, 67(272-273), 195 - 202
A comparative study of the activity of first and second generation cephalosporins and their combinations with beta-lactamase inhibitors against Bacteroides fragilis; Martin MA et al.; The sensitivity of 160 strains of Bacteroides fragilis, 74 beta-lactamase-positive and 86 negative, to two first generation and four second generation cephalosporins, alone and in combination with clavulanic acid and sulbactam, was investigated . For the susceptibility test the dilution method in agar was used . The detection of beta-lactamase production by this micro-organism was performed by means of the method using chromogenic cephalosporin of Nitrocefin . In both strains an important improvement in the activity of cephalothin, cephazolin, cefonicid and cefamandole was noted when they were combined with the two inhibitors . In combinations of cefoxitin and cefmetazole, no significant improvement was evident in the values of the parameters studied in the beta-lactamase-producing strains; and even in beta-lactamase-negative strains these values showed only a slight increase.

Drugs Exp Clin Res, 1991, 17(6), 299 - 304
Anaerobic osteomyelitis--treatment with metronidazole in an experimental rabbit model; Johansson A et al.; Anaerobic micro-organisms are important agents in chronic bone infections . Their pathogenic role, however, is still unclear partly because of methodological reasons . In this paper an experimental model of osteomyelitis is used for studies of metronidazole treatment of bone infections induced by Bacteroides fragilis . The proximal tibial metaphyses of ten New Zealand white rabbits were excavated and filled with sheets of polyvinyl alcohol, into which a suspension of B . fragilis cells was injected on the right side, while saline was used on the left side . Within a month the animals showed immunological and radiological signs of an established bone infection . After 25 weeks of observation, four animals were treated with subcutaneous injections of metronidazole at a dosage of 10 mg/kg body weight twice daily for three weeks and five animals received saline . After 37 weeks the animals were killed . Radiological, histological and microbiological evaluation showed bilateral osteomyelitis in all animals . Prolonged raised titres of antibodies suggested an established infection, and not merely a colonization . There were no differences between the animals treated with metronidazole and the animals not treated.

Acta Microbiol Pol, 1991, 40(1-2), 77 - 83
Serological activity of antigens isolated from 11 Bacteroides vulgatus strains; Rouyan GS et al.; Capsular (CPS) and phenol water (PW) extracts were prepared from 11 serogroup specific strains of B . vulgatus isolated from normal gut flora . The extracts were active in immunodiffusion (ID) and passive hemagglutination (HA) tests . There was no correlation between sugar and protein contents and serological activity of these extracts.

Infect Immun, 1991 Jan, 59(1), 295 - 301
Induction of interleukin-1 and -6 in human gingival fibroblast cultures stimulated with Bacteroides lipopolysaccharides; Takada H et al.; Normal human gingival fibroblasts stimulated in vitro by lipopolysaccharides (LPS) from oral Bacteroides species produced cell-free and cell-associated thymocyte-activating factors (TAF) . Neutralization assays using antisera to human interleukin-1 alpha (HuIL-1 alpha), HuIL-1 beta, and HuIL-6 revealed that cell-free TAF was attributable mainly to IL-1 beta and that IL-6 augmented the TAF activity of IL-1 beta in the culture supernatant . Another factor(s), however, may also be involved in cell-free TAF . By contrast, the active entity of cell-associated TAF was ascribed to IL-1 alpha alone . Furthermore, IL-6 was detected mainly in the supernatant of fibroblast cultures stimulated with Bacteroides LPS . Fibroblasts pretreated with natural human beta or gamma interferon, but not those pretreated with alpha interferon, synthesized higher levels of cell-associated IL-1 alpha in response to stimulation by Bacteroides LPS; however, no interferons exhibited direct IL-1-inducing activity or synergistic IL-1-inducing activity with LPS . Endogenously induced beta interferon was suggested to be necessary for fibroblasts to produce cell-associated IL-1 alpha in response to Bacteroides LPS.

Minerva Stomatol, 1991 Jan-Feb, 40(1-2), 71 - 5
{Anaerobic bacteria in oral infections of dental origin . The characteristics of Bacteroides species and diagnosis}; Anglesio Farina G et al.; Pyogenic orofacial infections are generally the result of a mixed aerobic and anaerobic infection . The aerobic germ, particularly the Bacteroides, have a prevailing role, even though their etiopathogenetic role is not clear yet.

J Med Microbiol, 1991 Jan, 34(1), 51 - 5
Surface components of Bacteroides fragilis involved in adhesion and haemagglutination; Oyston PC et al.; The ability of 19 strains of Bacteroides fragilis to adhere to buccal epithelial cells (BEC) and to the human intestinal cell line HT-29 Clone 19A, and to agglutinate rabbit erythrocytes was compared . Adhesion to BEC was poor compared with that to the cell line . Adhesion to the latter was high for 21% of the strains, moderate for 37% and poor for 42% . Only 53% of the strains agglutinated rabbit red blood cells and only strain A459 did so strongly . Haemagglutination and adhesion of B . fragilis strain A459 were inhibited by sodium periodate, but not by proteases, heat or carbohydrates . These properties were not affected by protease which removed surface appendages . Periodate treatment did not remove the fimbriae or ruthenium red-staining layer, although the capsule was lost . This suggests that carbohydrate residues on the cell surface, possibly forming part of the capsule, are involved in adhesion and haemagglutination by this strain.

Int J Biochem, 1991, 23(10), 1053 - 61
Purification and immunochemical characterization of a recombinant outer membrane protein from Bacteroides gingivalis; Kawamoto Y et al.; 1 . Bacteroides gingivalis is thought to be one of the most virulent microorganisms in relation to adult periodontitis . A gene clone, MD125, is an Escherichia coli host which produces an outer membrane protein of B . gingivalis . 2 . The recombinant outer membrane protein (rOMP) was purified to homogeneity from cell sonicate of MD125 by four chromatographic steps . The molecular weight of the purified rOMP was estimated to be approximately 40 kDa . 3 . Immunodiffusion analysis showed that antiserum against whole cells of B . gingivalis reacted not only with B . gingivalis cells but also with other Bacteroides cells . Antiserum against the purified recombinant protein reacted with cells of B . gingivalis, whereas this antiserum did not react with all of the other Bacteroides species tested . 4 . These data suggest that the rOMP may be a B . gingivalis-specific antigen and that the purified rOMP will be useful material for serodiagnosis and for the development of a vaccine against B . gingivalis infection.

Arch Oral Biol, 1991, 36(10), 709 - 14
Differential morphological changes in human polymorphonuclear leucocytes induced by culture products of Porphyromonas (Bacteroides) Gingivalis W50 and its colonial variants with reduced virulence; Scragg MA et al.; The colonial variants of W50, derived after growth in a chemostat and previously designated W50/BP1, W50/BR1 and W50/BE1, produced black-, brown- and beige-pigmented colonies, respectively, and showed reductions in mouse virulence and proteolytic activity correlating with their reduced pigmentation . Incubation of glass-adherent polymorphonuclear leucocytes with culture supernatants from the virulent, highly proteolytic, black-pigmented strain produced significant changes in morphology when compared with changes among sterile bacterial growth medium treated, control polymorphonuclear leucocytes . Large, non-polar cells (greater than or equal to 18 microns dia) increased by 130% (p less than 0.01) while polarized and small non-polar cells (less than 18 microns dia) decreased by 48 and 30% (p less than 0.05), respectively . Changes in percentages of the different morphological forms of polymorphonuclear leucocyte after exposure to the culture supernatant from the less virulent W50/BR1 variant showed similar, though less marked trends, while the avirulent W50/BE1 variant failed to produce significant changes in any morphological category . The specific activities of trypsin-like enzyme in the culture supernatants of the different variants were greater in black-pigmented than brown-pigmented and least in the beige-pigmented variant, thus correlating with the morphological changes in polymorphonuclear leucocytes . Morphological changes similar to those seen with culture supernatants from black-pigmented strains were reproduced by exposure of polymorphonuclear leucocytes to commercially available trypsin type II and prior heat treatment of these culture supernatants abolished the shape changes in polymorphonuclear leucocytes . Thus a bacterial, trypsin-like enzyme may play a role in the morphological changes observed.

Biochemistry, 1990 Dec 4, 29(48), 10757 - 65
Analysis of sequence homologies in plant and bacterial pyruvate phosphate dikinase, enzyme I of the bacterial phosphoenolpyruvate: sugar phosphotransferase system and other PEP-utilizing enzymes . Identification of potential catalytic and regulatory motifs; Pocalyko DJ et al.; In this paper we report the amino acid sequence of pyruvate phosphate dikinase (PPDK) from Bacteroides symbiosus as determined from the nucleotide sequence of the PPDK gene . Comparison of the B . symbiosus PPDK amino acid sequence with that of the maize PPDK {Matsuoka, M., Ozeki, Y., Yamamoto, N., Hirano, H., Kamo-Murakami, Y., & Tanaka, Y . (1988) J . Biol . Chem . 263, 11080} revealed long stretches of homologous sequence (greater than 70% identity), which contributed to an overall sequence identity of 53% . The circular dichrosim spectra, hydropathy profiles, and calculated secondary structural elements of the two dikinases suggest that they may have very similar tertiary structures as well . A comparison made between the amino acid sequence of the maize and B . symbiosus dikinase with other known protein sequences revealed homology, concentrated in three stretches of sequences, to a mechanistically related enzyme, enzyme I of the Escherichia coli PEP: sugar phosphotransferase system {Saffen, D . W., Presper, K . A., Doering, T . L., Roseman, S . (1987) J . Biol . Chem . 262, 16241} . It is proposed that (i) these three stretches of sequence constitute the site for PEP binding and catalysis and a possible site for the regulation of enzymatic activity and (ii) the conserved sequences exist in a third mechanistically related enzyme, PEP synthase.

Acta Odontol Scand, 1990 Dec, 48(6), 415 - 23
Associations between six DNA probe-detected periodontal bacteria and alveolar bone loss and other clinical signs of periodontitis; Albandar JM et al.; The purpose of the present study was to assess the associations between the presence and amounts of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B . intermedius, Eikenella corrodens, Wolinella recta, and Fusobacterium nucleatum in the periodontal pocket and the degree of alveolar bone loss and other clinical signs of periodonitis, such as probing pocket depth, attachment level, and presence of bleeding on probing at the same site . The study material comprised 16 subjects with or without approximal sites showing longitudinal alveolar bone loss who were selected from a group of 142 subjects monitored radiographically over the past 4 years . In this group 105 sites were examined, of which 58 showed recent alveolar bone loss greater than or equal to 1 mm . Subgingival plaque was collected with absorbent paper points and hybridized with 32P-labeled DNA probes specific for the above-mentioned bacteria . The amount of each bacterial species was correlated with the degree of bone loss over time and the three clinical measurements by means of Spearman rank correlation . A . actinomycetemcomitans showed poor correlations with all three clinical signs of periodontal inflammation, whereas B . gingivalis and W . recta demonstrated significant positive correlations with the three clinical measurements and with attachment level and pocket depth, respectively . In addition, the amount of A . actinomycetemcomitans, B . gingivalis and W . recta showed significant positive correlation with the extent of alveolar bone loss at the site . In contrast, the amounts of B . intermedius, E . corrodens, and F . nucleatum showed negative correlations with all four measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Wei Sheng Wu Xue Bao, 1990 Dec, 30(6), 433 - 7
{Physico-chemical and enzymological properties of beta-lactamase from Bacteroides fragilis}; Chen J et al.; Bacteroides fragilis 55 from clinical specimens was selected at random for beta-lactamase investigation of physico-chemical and enzymological properties . The enzyme was characterized as a cell-associated cephalosporinase with some penicillinase activity, the molecular weight of the enzyme being 43,000 and the pI 4.95 . It could be inhibited by cefoxitin, PCMB, carbenicillin, sulbactam, clavulanic acid and cloxacillin . The optimum pH and temperature for enzyme reactions have been found to be 7.2 and 37 degrees C, respectively . The analysis of amino acid composition and parameters of enzyme kinetics has been described.

Am J Obstet Gynecol, 1990 Dec, 163(6 Pt 1), 1938 - 43
A rabbit model for bacteria-induced preterm pregnancy loss; Dombroski RA et al.; Bacterial infection has been implicated in premature labor in humans . To elucidate mechanisms and potential intervention strategies, we sought to develop a model of infection-induced pregnancy loss in rabbits . On day 21 (70% of gestation), each uterine horn was inoculated hysteroscopically with 0.2 ml containing saline solution of 10(6) cfu Escherichia coli or Bacteroides bivius or Fusobacterium necrophorum . Fetal viability was assessed . Animals were sacrificed at various times or as delivery occurred . Serum progesterone and amniotic fluid prostaglandins were measured . Cultures and histologic sections were prepared . Compared with the saline solution group, E coli and F . necrophorum-inoculated rabbits were significantly more likely to deliver (16 of 16 and six of seven with mean times of 31.9 +/- 10.7 and 28.3 +/- 11.5 hours, respectively for E . coli and F . necrophorum) . Positive amniotic fluid cultures for the E . coli group were found in 11 of 12 (92%) and for the F . necrophorum group in three of three cases (100%) . Histologic inflammation was seen heavily in both the E . coli and F . necrophorum groups, whereas it was absent in the saline solution group . Inoculation with B . bivius led to a much lower pregnancy loss rate (eight of 32) and less histologic inflammation despite positive uterine cultures in most animals . This model may provide an opportunity to determine mechanisms of clinical or subclinical intraamniotic infection and to test intervention strategies.

J Trauma, 1990 Dec, 30(12 Suppl), S49 - 57
Endotoxin requirements for alveolar macrophage stimulation; Maier RV et al.; Acute pulmonary failure or ARDS in severely injured patients continues to be a significant problem . The most important clinical risk factor identified is sepsis syndrome . Sepsis syndrome is the clinical correlate of a malignant systemic inflammatory process and is directed in large part by the tissue-fixed macrophage (M phi), such as the alveolar M phi . The M phi is capable of producing most of the central inflammatory mediators responsible for the pathophysiology seen during sepsis and organ injury . Two major mediators are procoagulant activity (PCA), leading to diffuse microvascular thrombosis, and tumor necrosis factor (TNF), causing much of the physiologic derangement of sepsis . Endotoxins (LPS) derived from Gram-negative bacterial cell walls are the primary inflammatory stimulus for the tissue-fixed M phi production of inflammatory mediators . It is not completely known how LPS interacts with its various cellular targets, but it is hoped that knowledge of the molecular interactions involved in stimulation of the M phi by endotoxin will lead to therapies to modulate the response and prevent deleterious processes such as ARDS . In the present studies, LPS from E . coli 0111:B4 was shown in a dose response to stimulate large levels of both PCA and TNF in alveolar M phi . LPS from Bacteroides fragilis and Lipid X (the monosaccharide precursor of endotoxin) were unable to cause stimulation of the M phi in vitro . However, both moieties, B . fragilis LPS and Lipid X, were able to effectively and specifically compete with E . coli LPS and block M phi stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Immun, 1990 Dec, 58(12), 4016 - 9
Hemin levels in culture medium of Porphyromonas (Bacteroides) gingivalis regulate both hemin binding and trypsinlike protease production; Carman RJ et al.; Washed cells and Sarkosyl-insoluble outer membrane preparations of the black-pigmented bacteroides Porphyromonas gingivalis W50 bound hemin . The amount of hemin removed from a buffered solution by both cells and outer membranes was significantly larger if bacteria had been grown in broths supplemented with 5 mg of hemin per liter rather than none . Conversely, cells grown without supplemental hemin bound relatively little . However, all preparations bound some hemin . In addition, hemin regulated the production of significantly higher levels of trypsinlike protease by P . gingivalis W50 . The nonpigmented variant, W50 BE1, showed no such responses to the levels of hemin in the growth medium.

Infect Immun, 1990 Dec, 58(12), 3954 - 8
Iron-regulated outer membrane protein of Bacteroides fragilis involved in heme uptake; Otto BR et al.; Under iron starvation, Bacteroides fragilis expresses various iron-regulated outer membrane proteins . In this study, a deferrated minimal medium was used in growth experiments, and the role of one of these iron-regulated outer membrane proteins (a 44-kDa protein) in an iron uptake mechanism which acquires iron from heme compounds was elucidated . When a specific 44-kDa protein antiserum was used in a medium with heme as the only iron source, growth inhibition was observed . These results demonstrate that the 44-kDa outer membrane protein plays an important role in the uptake of heme in B . fragilis.

Osaka Daigaku Shigaku Zasshi, 1990 Dec, 35(2), 447 - 64
{Preparation and application of monoclonal antibodies against sialoglycoprotein purified from human submandibular-sublingual saliva}; Takagaki M; Sialoglycoprotein (SGP) having relatively high molecular weight was purified from human submandibular sublingual saliva by anion exchange chromatography on Q-Sepharose Fast Flow followed by gel filtration on Superose 6 prep grade . The molecular weight of SGP was estimated to be about 440,000 and the isoelectric points obtained by IEF-PAGE, ranged from 5.2 to 5.8 . The purified SGP contained high compositions of glutamic acid, proline, glycine and aspartic acid which were calculated as about 57% of the total amino acids, and about 15% of sugars such as N-acetylneuraminic acid, galactose, fucose, mannose, N-acetylgalactosamine and N-acetylglucosamine . A panel of 23 murine monoclonal antibodies (MAbs; 8 IgG1, 15 IgM) directed against SGP was prepared . Although three protein components were detected by SDS PAGE, SGP specific MAb reacted intensely with a 60 kilodalton of protein component . Bacteroides gingivalis 381 showed high binding ability to SGP, but this interaction was inhibited by SGP specific MAb . To detect SGP in the pellicle formed on fragments of human dental enamel, SGP specific MAb were used . During the first hour of formation, rapid increase of SGP detected was observed, and it remained relatively unchanged between 1 and 24 h after beginning of pellicle formation . This work has suggested that SGP purified from submandibular-sublingual saliva is a main component of salivary pellicle on tooth surface and plays an important role in the interaction with oral bacteria including Bacteroides gingivalis.

J Periodontol, 1990 Dec, 61(12), 755 - 62
A family study of a mother and daughter with increased susceptibility to early-onset periodontitis: microbiological, immunological, host defensive, and genetic analyses; Nishimura F et al.; Microbiological, immunological, host-defensive, and genetic analyses were performed on a mother and daughter, both of whom had early-onset periodontitis (rapidly progressive periodontitis in the mother; localized juvenile periodontitis in the daughter) . Microscopic examination revealed a greatly elevated percentage of rod-form bacteria in both subjects . Fusobacterium sp . and Porphyromonas gingivalis (formerly Bacteroides gingivalis) were the predominant microorganisms cultured . The humoral immune responses to F . nucleatum, P . gingivalis, and Actinobacillus actinomycetemcomitans were much higher in both subjects than those to any other periodontal bacteria examined . Functional and phenotypic analysis of the peripheral lymphocytes showed no significant abnormalities . However, investigation of neutrophil function showed that the mother had depressed neutrophil chemotaxis and superoxide production . The daughter had depression not only of chemotaxis and superoxide production, but also of neutrophil phagocytosis . Serological typing of HLA antigens revealed the same Class II HLA profile in both subjects . It was concluded that both subjects very probably had an identical condition and that these patients provided a unique model for improving our understanding of the host factors involved in periodontal disease.

Clin Oral Implants Res, 1990 Dec, 1(1), 1 - 7
Microbiological features of stable osseointegrated implants used as abutments for overdentures; Mombelli A et al.; The microflora associated with osseointegrated implants used as abutments for overdentures was investigated in 18 edentulous patients, 2 years after implantation . 52.8% of the organisms cultured were facultatively anaerobic cocci and 17.4% were facultatively anaerobic rods, while Gram-negative anaerobic rods accounted for only 7.3% . Fusobacterium sp . and Bacteroides intermedius were both found in 8.8% of the samples . B . gingivalis and spirochetes were not found . Repeated microbiological and clinical data were collected in 9 patients during the 3rd, 4th and 5th year after implantation . No significant time trends were noted . Separate samples taken within the same patient from different sites were similar . Therefore, bacteriological independence of sites could not be assumed for the conditions investigated.

Oral Microbiol Immunol, 1990 Dec, 5(6), 360 - 2
Purification and characterization of a 43-kDa protease of Bacteroides gingivalis; Fujimura S et al.; From the culture supernatant of Bacteroides gingivalis ATCC 33277, a thiol protease was purified to homogeneity by fractional ammonium sulfate precipitation, ion-exchange chromatography, gel filtration, and isoelectric focusing . Its molecular weight was 43 kDa and showed similar enzymatic properties to a 300-kDa protease that was previously characterized.

Oral Microbiol Immunol, 1990 Dec, 5(6), 332 - 5
Black-pigmented, asaccharolytic Bacteroides species resembling Porphyromonas gingivalis (Bacteroides gingivalis) from beagle dogs; Yamasaki T et al.; Black-pigmented, asaccharolytic Bacteroides strains, which positively reacted with anti-Bacteroides gingivalis (now reclassified as Porphyromonas gingivalis) serum, were isolated from beagle dogs, and their characteristics were studied and compared with those of P . gingivalis . The strains from dogs were different from P . gingivalis in their catalase activity, nutritional requirements and oxygen tolerance, and double-immunodiffusion tests showed serological dissimilarity between the strains from dogs and P . gingivalis . However, the strains from dogs had guanine-plus-cytosine contents of 49.0 to 49.3 mol %, which were very similar to P . gingivalis, and they showed strong DNA-DNA hybridization with P . gingivalis . These results indicated that beagle dogs had Porphyromonas species analogous to P . gingivalis in their oral cavities.

Arch Intern Med, 1990 Dec, 150(12), 2525 - 9
Clindamycin vs penicillin for anaerobic lung infections . High rate of penicillin failures associated with penicillin-resistant Bacteroides melaninogenicus; Gudiol F et al.; Thirty-seven adult patients with anaerobic lung infections (27 lung abscesses and 10 necrotizing pneumonias) were submitted to transthoracic needle-aspiration and/or bronchoscopic specimen brush cultures before therapy and thereafter in all cases considered to be failures . Patients were randomly assigned to receive either clindamycin, 600 mg intravenously every 6 hours, or penicillin G, 2 million U every 4 hours for no less than 8 days, until clinical and radiological improvement became apparent . Treatment was continued orally with clindamycin, 300 mg every 6 hours, or penicillin V, 750 mg every 6 hours, until completing a minimum of 4 weeks . Ten of the 47 anaerobes initially isolated from the lung (nine Bacteroides melaninogenicus and one Bacteroides capillosus) were resistant to penicillin, but none were resistant to clindamycin . Five of the nine patients harboring these penicillin-resistant Bacteroides received penicillin, and all failed to respond to therapy . Overall, eight of the 18 patients in the penicillin group and one of 19 in the clindamycin group failed to respond to therapy . These drugs were equally well tolerated in both groups . The presence of penicillin-resistant Bacteroides is a frequent cause of penicillin failure in patients with anaerobic lung infections . In this setting, clindamycin appears to be the current therapy of choice for initial treatment.

Kanagawa Shigaku, 1990 Dec, 25(3), 327 - 37
{Studies on immunobiological activities of periodontopathic bacteria . Comparison of the activities of soluble components from Bacteroides gingivalis and Actinomyces viscosus}; Matsubara K; It has been proposed that Bacteroides gingivalis and Actinomyces viscosus are most important agents to pathogenesis of the periodontitis and gingivitis . In this study, the influences of sonic extracts prepared from B . gingivalis and A . viscosus for DNA synthesis of murine lymphocytes, production of prostaglandin E2 (PGE2), collagenase and interleukin-1 (IL-1) from human peripheral monocyte were investigated . Furthermore, PGE2 and collagenase production by fibroblasts from human periodontal ligament (HPLF) and gingiva (Gin 1) stimulated with macrophage conditioned medium (MCM) cultured with bacterial sonic extracts were examined . The results obtained were as follows . 1 . The sonic extracts (10 micrograms/ml protein) from B . gingivalis and A . viscosus showd low mitogenic activity to spleen cells, however, induced polyclonal B cell activation . 2 . Although, the effect of these sonic extracts on the production of PGE2 and collagenase by human peripheral monocyte was not found, the induction of IL-1 production was recognized . 3 . The culture supernatants of C3H/HeN mouse peritoneal macrophage stimulated with sonic extracts of B . gingivalis and A . viscosus were induced PGE2 and collagenase production by HPLF and Gin 1 . These results suggest that the cellular components of B . gingivalis and A . viscosus may play the pathogenic roles in periodontal tissue destruction through the stimulation of macrophage and/or lymphocyte.

Osaka Daigaku Shigaku Zasshi, 1990 Dec, 35(2), 465 - 85
{Purification, characterization and induction by oxygen of superoxide dismutase from Bacteroides gingivalis 381}; Amano A; Several strains of Bacteroides gingivalis had strong activities of superoxide dismutase (SOD) and were markedly tolerant in the presence of oxygen in 13 strains of black-pigmented Bacteroides species tested . Thus, the strains were maintained and incubated in the either anaerobic or aerobic system . It was found that the SOD activity was significantly induced by oxygen, especially in B . gingivalis 381 . The SODs, anaero-SOD and aero-SOD from the extracts of B . gingivalis 381 cells, each was purified by hydrophobic chromatography followed by anion exchange chromatography, and then by gel filtration, respectively . Both the purified enzymes having molecular weight of about 46,000 consisted of two subunits of equal sizes . Spectral analysis revealed that anaero-SOD had the characteristic A350 of Fe-SOD, but aero-SOD exhibited A475 of Mn-SOD . Both samples contained three isozymes with identical isoelectric points of 5.25, 5.10 and 5.00 . On the basis of inactivation of SOD by H2O2, it was shown that aero-SOD consisted of one Mn-SOD and a small quantity of two Fe-SODs, whereas anaero-SOD contained only Fe-SOD . To ascertain whether or not the apoprotein of aero-SOD is the same as that of anaero-SOD, each apoprotein was prepared by dialysis in guanidinium chloride plus 8-hydroxyquinoline . Only one protein band with the same isoelectric point of 5.30 on an isoelectric focusing gel was obtained in each purified SOD sample . Subsequent reconstitution of both apoenzymes with either Fe (NH4)2 (SO4)2 or MnCl2 significantly restored their activity . These reconstituted SODs showed only one protein band with SOD activity on Native-PAGE . The complete amino acid sequence of anaero-SOD was determined by automated Edman degradation of the protein, Achrombacter protease I, endoproteinase Asp-N and tryptic digestion . The sequence consisted of 191 residues corresponding to a molecular weight of 21,500 per subunit . Furthermore, the first 36 amino acid sequence of aero-SOD was determined following N-terminal analysis . The two enzymes had similar amino acid compositions, and their amino-terminal sequences were identical through the first 36 amino acids in which methionine residue was present at N-terminal . These results suggest the three isozymes of either anaero-SOD or aero-SOD in B . gingivalis 381 may be formed from the same apoprotein.

Appl Environ Microbiol, 1990 Dec, 56(12), 3867 - 70
Utilization of nucleic acids by Selenomonas ruminantium and other ruminal bacteria; Cotta MA; Species of ruminal bacteria were screened for the ability to grow in media containing RNA or DNA as the energy source . Bacteroides ruminicola D31d and Selenomonas ruminantium HD4, GA192, and D effectively used RNA for growth, but not DNA . B . ruminicola D31d was able grow on nucleosides but not on bases or ribose . The S . ruminantium strains were able to grow when provided with either nucleosides or ribose but not bases . Strains of S . ruminantium, but not B . ruminicola D31d, were also able to use nucleosides as nitrogen sources . These data suggest that RNA fermentation may be a general characteristic of S . ruminantium.

Gene, 1990 Nov 30, 96(1), 149 - 50
The superoxide dismutase-encoding gene of the obligately anaerobic bacterium Bacteroides gingivalis; Nakayama K; The gene (sod) encoding the superoxide dismutase (SOD) of the obligately anaerobic bacterium Bacteroides gingivalis was cloned . The amino acid (aa) sequence of the SOD, deduced from the nucleotide sequence of the sod gene, basically resembled that of known Fe-SODs . However, the aa sequence of the B . gingivalis SOD was found to be intermediate between those of Fe-SOD and Mn-SOD in a limited region around the putative second ligand, where major differences between the aa sequences of Fe-SOD and Mn-SOD are known to exist.

J Appl Bacteriol, 1990 Nov, 69(5), 697 - 700
Growth of Bacteroides fragilis group in agar and broth media; Brook I; The rate of bacterial growth of four Bacteroides fragilis group organisms was determined in agar and broth media . Exponential bacterial growth occurred in agar media within 4 to 8 h, while such growth was delayed in broth media and occurred within 12-24 h after inoculation . This phenomenon may explain why antimicrobials which manifest an 'inoculum effect' may show increased resistance to antimicrobials when tested in agar media.

J Periodontol, 1990 Nov, 61(11), 692 - 8
The effect of clindamycin on the microbiota associated with refractory periodontitis; Walker C et al.; The purpose of this investigation was to determine the effect of clindamycin hydrochloride, as an adjunct to scaling, on the microbiota associated with refractory periodontitis and to elucidate the probable causative bacteria associated with the disease . Microbial samples were collected from a subset of 9 patients with severe adult periodontitis who had not responded to conventional treatment modalities including the use of tetracycline and other antibiotics . Microbial samples were collected from a relatively deep site determined to be actively losing attachment and a comparably deep, but quiescent, control site in each patient prior to clindamycin therapy . Samples continued to be collected from the same sites for up to 1 year post-therapy . The microbial flora of each sample were enumerated by darkfield microscopy and predominant cultivable methods . Prior to clindamycin therapy, both active and control sites consisted on average of approximately 50% spirochetes and motile rods and 40% Gram-negative anaerobic rods . Bacteroides intermedius and Porphyromonas gingivalis (formerly B . gingivalis) were elevated in the active, as compared to control, sites and accounted for approximately 20% of the cultured microbiota in the former . Following treatment with clindamycin, the Gram-negative components of the microbiota were either eliminated or severely suppressed . At 1 year post-therapy, spirochetes and motile rods together accounted for about 15% of the microscopic flora . Total Gram-negative anaerobic rods accounted for approximately 20%, and B . intermedius and P . gingivalis combined accounted for less than 2% of the cultured microbiota from historical active sites.(ABSTRACT TRUNCATED AT 250 WORDS)

J Clin Microbiol, 1990 Nov, 28(11), 2389 - 93
Irrigation-aspiration for culturing draining decubitus ulcers: correlation of bacteriological findings with a clinical inflammatory scoring index; Ehrenkranz NJ et al.; Biopsy of infected decubitus ulcers for culture disrupts tissues and may disseminate infection . Antimicrobial prophylaxis to prevent dissemination of infection may adversely affect biopsy culture results . Irrigation-aspiration to obtain submarginal specimens from draining decubitus ulcers was studied as an atraumatic, noninvasive culturing technique to serve as an alternative to biopsy in research activities . Two aspirates were obtained serially from 32 subjects; in 12 subjects, biopsies were also performed immediately . A median of 4.5 bacterial species was recovered per ulcer by irrigation-aspiration . Recent antimicrobial treatment had no evident effect on the recovery of bacterial species in general or, specifically, on the recovery of Bacteroides species . Concordance of results for both aspirates was 97.6% for aerobes and 91.8% for anaerobes, indicating no interactive methodological effect of the first irrigation-aspiration on the second . Compared with biopsy isolates for one aspirate, the sensitivity was 93% and the specificity was 99.0%; for another aspirate, the sensitivity was 94.7% and the specificity was 99.5% . The positive predictive value for either aspirate was greater than or equal to 93.9% . A weighted clinical index to score inflammatory ulcer characteristics was devised (score range, 0 to 15) . In the absence of anaerobes in 15 subjects, the mean score was 6.1 +/- 3.5; in the presence of anaerobes in 17 subjects, the mean score was 9.4 +/- 3.2 (P = 0.008) . The presence of aerobic gram-positive or gram-negative species did not significantly affect scores . Irrigation-aspiration for culture and clinical scoring of inflammation should permit independent serial measures of bacteriological and clinical courses of draining decubitus ulcers without patient risk or discomfort.

J Periodontal Res, 1990 Nov, 25(6), 339 - 46
Alterations in cell morphology and cytoskeletal proteins in gingival fibroblasts exposed to a Bacteroides gingivalis extract; Phillips JR et al.; A soluble sonic extract (SSE) from Bacteroides gingivalis caused a dose-dependent inhibition of gingival fibroblast growth, reduced cell attachment and altered cell morphology . Most of its cytotoxic activity was destroyed by heating, indicating that the factor(s) was a protein rather than endotoxin . Cells, grown in the presence of, or on, root surfaces pretreated with 100-200 micrograms SSE/ml, partially retracted from the substratum and exhibited extensive surface blebbing and finger-like protrusions . Immunofluorescent staining showed that the morphological effects of Bacteroides gingivalis SSE are directed specifically at actin stress fibers and not microtubules of the cytoskeleton . Exposure to the SSE resulted in a dramatic relocalization of the bulk of F-actin from a fibrous form to a non-aggregated diffuse form . Disorganization of actin stress fibres occurred at concentrations of SSE that inhibited cell growth, but preceded any observable changes in cell attachment or morphology . The microtubular network remained intact, although it stained less intensely than that of controls . By contrast, Bacteroides intermedius SSE did not significantly influence growth, alter cellular morphology or affect the two cytoskeletal proteins.

J Periodontal Res, 1990 Nov, 25(6), 331 - 8
Microbial changes associated with the development of puberty gingivitis; Mombelli A et al.; In this study, longitudinal changes in the composition of the subgingival microbiota of children between the ages of 11 and 14 and their association with changes of clinical parameters describing gingival health were investigated . During 4 years, subgingival microbial samples were taken in 22 boys and 20 girls 10 times . At the same time the gingival bleeding tendency was recorded by the Papillary Bleeding Index (PBI) . A total of 840 samples was evaluated using darkfield microscopy and anaerobic culturing on non-selective and selective media . Children, who developed a marked and sustained increase in mean PBI scores (n = 21), had higher frequencies and mean proportions of spirochetes and Eikenella corrodens than children without pronounced puberty gingivitis (p less than = 0.05) . The mean proportion of Actinomyces viscosus was also higher in these children (p less than = 0.05) . Among the species discriminated, only Capnocytophaga sp . were found at a higher rate in samples taken immediately before a rise of PBI (p less than = 0.05) . The detection frequencies of black-pigmented Bacteroides (particularly B . intermedius) increased later, and were significantly elevated after the establishment of a high bleeding tendency (p less than = 0.05) . These findings implicate Capnocytophaga sp . in the initiation of puberty gingivitis, whereas the increased presence of Bacteroides may reflect a change in the subgingival environment secondary to increased bleeding.

Eur J Clin Microbiol Infect Dis, 1990 Nov, 9(11), 825 - 6
Isolation of Bacteroides ureolyticus from the genital tract of men with and without non-gonococcal urethritis; Bennett KW et al.; Urethral specimens from 247 heterosexual men--118 patients with non-gonococcal urethritis and 129 controls with no evidence of urethritis--were examined for the presence of Bacteroides ureolyticus . Bacteroides ureolyticus was isolated from 45 (34.9%) of the controls and from 31 (26.3%) of the urethritis patients; there was no significant difference between these rates (p = 0.1) . There was no association between the density of Bacteroides ureolyticus on primary isolation plates in either group.

FEMS Microbiol Lett, 1990 Nov, 60(3), 275 - 9
Purification and characterization from human parotid secretion of a peptide which inhibits hemagglutination of Bacteroides gingivalis 381; Murakami Y et al.; A peptide from human parotid secretion which inhibited hemagglutination of Bacteroides gingivalis 381 was purified by ultrafiltration followed by DEAE-Sephadex A-25 column chromatography and by gel filtration on Sephadex G-25, and then by reversed-phase HPLC . The complete amino acid sequence of the peptide, determined by automated Edman degradation was as follows; Lys-Phe-His-Glu-Lys-His-His-Ser-His-Arg-Gly-Tyr . The peptide contained 12 residues and the charged amino acids predominated with 4 histidine, 2 lysine, 1 arginine and 1 glutamic acid residues, thus being a histidine-rich peptide . The peptide was an active inhibitor of the hemagglutinating activity of B . gingivalis . Specific binding of tritium-labeled peptide to B . gingivalis cells was demonstrated . These results suggest that the histidine-rich peptide may function as a binding domain for the hemagglutinins of B . gingivalis during agglutination.

J Antimicrob Chemother, 1990 Nov, 26(5), 649 - 57
The effects of tetradecyl-4-ethyl-pyridinium chloride on the maximum specific growth rate biomass and hydrolytic enzyme production of Bacteroides gingivalis in continuous culture; Greenman J et al.; Bacteroides gingivalis was grown in continuous culture in the presence of tetradecyl-4-ethyl-pyridinium chloride (TDEPC) . The maximum specific growth rate and biomass levels decreased with increasing concentrations of antimicrobial and complete inhibition of growth occurred when the TDEPC concentration reached 40 mg/l . Hydrolytic enzymes were detected in cells, vesicles and supernatant fractions of whole culture . Levels of alkaline phosphatase initially increased with increasing concentrations of TDEPC, but at higher concentrations (15-20 mg/l) of antimicrobial decreased significantly to less than 20% of the control value . The levels of N-acetyl-beta-glucosaminidase remained approximately constant at lower concentrations of TDEPC (0 10 mg/l) but then decreased significantly at higher concentrations . In contrast, levels of trypsin-like protease were reduced significantly at even low concentrations of TDEPC (5 10 mg/l) and decreased further as the TDEPC concentration increased . Therefore, TDEPC exerts significant physiological effects on B . gingivalis at concentrations below those considered to be lethal to the cell.

Infection, 1990 Nov-Dec, 18(6), 367 - 71
Pharmacokinetics of imipenem in patients undergoing major colon surgery; Erttmann M et al.; Ten patients about to undergo a colorectal operation lasting an average of three hours received 500 mg each of imipenem and cilastatin i.v . preoperatively . During the operation blood and tissue samples were taken in order to determine the serum kinetics of the substances as well as the levels of imipenem in the cutis, subcutis, fascia, muscle, parietal peritoneum and colon . The imipenem concentrations were measured by HPLC . The mean peak serum concentration was 26 mg/l, the mean half-life 55 min and the AUC 40 mg/l/h-1 . The serum pharmacokinetics of imipenem was subject to substantially larger fluctuations in this patient group than in subjects or patients without surgery . Imipenem rapidly penetrates into tissue, with peak concentrations being reached after 10-25 min . The highest imipenem concentrations were found in the colon, the lowest in the cutis and subcutis . After 1 h a level of 8 mg/kg imipenem was still found in the colon . The concentrations were greater than 1 mg/kg in all tissues for more than 3 h p . a . and thus within this period exceeded the MICs of Escherichia coli and Bacteroides fragilis, the indicator organisms of intraabdominal infections.

Dtsch Tierarztl Wochenschr, 1990 Nov, 97(11), 482 - 90
{The etiology of "Cara inchada," a periodontal disease of young cattle in Brazil}; Dobereiner J; A sequence of research on "Cara inchada", a periodontal disease of young cattle (CI), involving heavy losses in Brazil, is described and results of laboratory investigations and field experiments are reported . A suspicion of being a primary nutritional disease of the skeleton could not be confirmed . In the other hand, bacteria, especially of the genus Bacteroides, were isolated from the periodontal CI-lesions . These bacteria possess enough pathogenic potential, through the production of enzymes and endotoxins, to cause primary destruction of the periodontal tissues . The lesions of the upper jaw, and also of the mandibula, of the diseased animals were diagnosed as a purulent periodontitis and a secondary ossifying alveolar periostitis . As CI occurs enzootically on new, cultivated pastures in cleared forest and savanna areas, and as the incidence of the disease declines with the years of pasture use, in order to disappear again, it can be postulated that a determining factor exists in the soil and consequently in the pasture, the disturbance of the equilibrium of the microflora in the formerly virgin soil possibly causes a modification of the flora of the rumen and the oral cavity, so that bacteria, as Bacteroides spp., present in the subgingival space, could dominate and become pathogenic . The frequent diarrhoea observed in calves affected by CI could be a consequence of the modification of the microflora in the digestive tract . Accordingly, CI could be considered as an infectious periodontitis of calves due to altered ecological soil conditions.

Antimicrob Agents Chemother, 1990 Nov, 34(11), 2246 - 9
Statistical analysis of the effects of trial, reader, and replicates on MIC determination for cefoxitin; Wexler HM et al.; A pilot study was designed to estimate the variance components in the determination of the MIC of cefoxitin for isolates of the Bacteroides fragilis group . Twenty different organisms were tested, and replicate, trial, and reader variabilities were examined . When the total-variance component was used, if the true MIC was 16 micrograms/ml, then the chance that the observed MIC was between 8 and 32 micrograms/ml, inclusive, was 95% . For all analyses, the isolate (P = 0.0001) and reader (P less than 0.03) effects were significant . The probability of specific MIC observations for various true MICs (over the range of 16 to 32 micrograms/ml at 4-micrograms/ml increments) was calculated . For true MICs of 20, 24, and 28 micrograms/ml, the probabilities of observing an MIC of 16 or 32 micrograms/ml (inclusive) were 86, 75, and 62%, respectively . An upward bias was shown to exist in addition to sources of sizeable variation . The recommendation stemming from recognition of this inherent variability is that ranges of percent susceptibility at various concentrations be included in reports of in vitro susceptibility studies.

Antimicrob Agents Chemother, 1990 Nov, 34(11), 2169 - 76
Characterization of beta-lactamases from non-Bacteroides fragilis group Bacteroides spp . belonging to seven species and their role in beta-lactam resistance; Appelbaum PC et al.; Twelve beta-lactamase-positive non-Bacteroides fragilis group Bacteroides spp . belonging to seven different species were examined by MIC determination and enzyme characterization . MICs of most beta-lactams except cefoxitin, cefotetan, imipenem, and meropenem were relatively high or very high . All enzymes hydrolyzed cephaloridine (Vmax, 100%; Km, 12 to 70 microM), cephalothin (Vmax, 25 to 826%; Km, 8 to 143 microM), cefamandole (Vmax, 13 to 158%; Km, 17 to 170 microM), and cefuroxime (hydrolysis rate, 19 to 98%), and 11 of 12 hydrolyzed cefotaxime (Vmax, 26 to 145%; Km, 13 to 127 microM); no hydrolysis of cefoxitin or moxalactam was observed . Penicillins were hydrolyzed at lower rates, with Vmax values less than or equal to 20% of that obtained with cephaloridine . Addition of clavulanate, sulbactam, or tazobactam led to a 4- to 2,048-fold lowering of MICs of penicillins as well as cephalosporins . All enzymes were inhibited by clavulanate (50% inhibitory concentration {IC50}, 0.01 to 1.8 microM), sulbactam (IC50, 0.02 to 1.9 microM), tazobactam (IC50, 0.001 to 0.9 microM), cefoxitin (IC50, 0.002 to 0.35 microM), and moxalactam (IC50, 0.03 to 6.6 microM) . No enzymes were inhibited by 100 microM EDTA or p-chloromercuribenzoic acid; an enzyme of one strain of B . loescheii was inhibited by 100 microM cloxacillin (IC50, 2.35 microM) . Ten enzymes had optimal activity at pH 5.0 to 6.0, and two had optimal activity at pH 8.0 . Isoelectric focusing revealed pIs between 4.2 and 5.6 . These enzymes seem to belong to a previously unclassified group of beta-lactamases, related (but not identical) to beta-lactamases of the B . fragilis group.

J Clin Microbiol, 1990 Nov, 28(11), 2456 - 61
Polymerase chain reaction amplification of the constant and variable regions of the Bacteroides nodosus fimbrial gene; John GH et al.; Serogrouping of Bacteroides nodosus is based on antigenic differences in fimbriae of the different New Zealand prototype strains . Because of the time needed to isolate and grow pure cultures of B . nodosus and the difficulty in distinguishing between different serogroups because of cross-agglutination, a new DNA-based diagnostic approach based on the fimbrial gene sequence of B . nodosus was developed . Published nucleotide sequences of the fimbrial genes for serogroups A, G, D, and H showed conservation at the 5' end, coding for the N terminus, and variability at the 3' end, coding for the C terminus . The polymerase chain reaction was used to amplify both the constant and variable regions of the fimbrial genes . Constant-region oligonucleotide primers were used to amplify a 100-base-pair fragment from the constant regions of the fimbrial genes of 10 New Zealand serogroups . Serogroup-specific oligonucleotide primers for serogroups A and H allowed amplification of a 282-base-pair fragment from serogroup A and a 363-base-pair fragment from serogroup H . Thus, amplification of the constant and variable regions of the fimbrial gene allows rapid detection and grouping of B . nodosus.

Clin Exp Immunol, 1990 Nov, 82(2), 318 - 25
Bacteroides gingivalis-specific serum IgG and IgA subclass antibodies in periodontal diseases; Ogawa T et al.; The level of serum IgM, IgG and IgA antibodies including IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2 subclass-specific antibodies to Bacteroides (Porphyromonas) gingivalis fimbriae and to lipopolysaccharide (LPS) were analysed in patients with different forms of periodontal disease (PD) and control subjects by ELISA . Among PD subjects, sera obtained from adult periodontitis (AP), rapidly progressive periodontitis (RPP) and gingivitis contained high titres of fimbriae-specific IgG antibodies (7500-15,000 ELISA units) followed by IgA (90-700 units) and IgM (30-90 units) . In contrast, sera from localized juvenile periodontitis (LJP) subjects exhibited much lower titres of fimbriae-specific IgG (89 +/- 11 units), IgA (31 +/- 5 units) and IgM (17 +/- 3 units) antibodies . A similar response pattern was also seen in sera from normal subjects aged 35-41 years who practice normal oral hygiene, while sera of younger adults (aged 18-24) with superior hygiene did not have any antigen-specific antibodies . Analysis of IgG subclass anti-fimbriae responses revealed that the major response was IgG3 followed by IgG1, IgG2 and IgG4 in AP, RPP and gingivitis . Although lower, a similar pattern of IgG subclass titre was seen in LJP and normal subjects aged 35-41 years . When IgA subclass responses were measured in AP and RPP, higher titres of the fimbriae-specific response were noted with IgA1 when compared with IgA2 . However, lower but approximately equal levels of fimbriae-specific IgA1 and IgA2 titres were seen in other PD groups . When anti-B . gingivalis LPS-specific responses were measured, the sera of AP patients contained high levels of IgG antibodies (2265 +/- 224 units) followed by IgA (411 +/- 90 units) and IgM (214 +/- 56 units) . Further, IgG anti-LPS responses were mainly IgG2 followed by IgG4, IgG3 and IgG1 . For IgA subclass responses, higher titres of anti-LPS-specific antibodies were noted in IgA2 subclass over IgA1 . These results showed that higher anti-B . gingivalis antibody responses occur in PD when compared with healthy individuals and protein and lipid-carbohydrate antigens of B . gingivalis induce distinct patterns of antigen-specific IgG and IgA subclass responses.

Bull Tokyo Dent Coll, 1990 Nov, 31(4), 321 - 31
Clinical, microbiological, and immunological studies following initial preparation in adult periodontitis; Nakagawa T et al.; This study investigated the clinical, microbiological and immunological changes induced in adult periodontitis by initial preparation . Microflora in periodontal lesions was mainly examined by cultural methods, and serum IgG antibody levels were measured by an enzyme linked immunosorbent assay . Black-pigmented gram negative anaerobes, especially Porphyromonas (Bacteroides) gingivalis, was predominant in periodontal pockets with adult destructive periodontitis . Significantly elevated serum IgG antibody levels to P . gingivalis was found in high frequency, and these serum IgG antibody levels correlated with the presence of P . gingivalis in periodontal pockets, not with other bacteria tested . Total-CFU was significantly reduced and clinical conditions were improved after supragingival plaque control, but the microflora themselves showed few changes . Although reduction of total-CFU and changes in microflora were observed following scaling and root planing, it was found to be difficult to completely eliminate periodontopathic bacteria from periodontal pockets . Although serum IgG antibody levels to P . gingivalis was significantly reduced following initial preparation, the levels were still elevated from those of the controls . It was found that the presence of P . gingivalis was correlated with clinical conditions, including bleeding on probing and residual pocket depth following initial preparation.

FEBS Lett, 1990 Oct 15, 272(1-2), 217 - 20
The primary structure of superoxide dismutase purified from anaerobically maintained Bacteroides gingivalis; Amano A et al.; The superoxide dismutase (SOD) of Bacteroides gingivalis can use either iron or manganese as a cofactor in its catalytic activity . In this study, the complete amino acid sequence of this SOD purified from anaerobically maintained B . gingivalis cells was determined . The proteins consisted of 191 amino acid residues and had a molecular mass of 21,500 . The sequence of B . gingivalis SOD showed 44-51% homology with those for iron-specific SODs (Fe-SODs) and 40-45% homology with manganese-specific SODs (Mn-SODs) from several bacteria . However, this sequence homology was considerably less than that seen among the Fe-SOD (65-74%) or Mn-SOD family (42-60%) . This indicates that B . gingivalis SOD, which accepts either iron or manganese as metal cofactor, is a structural intermediate between the Fe-SOD and Mn-SOD families.

Infect Immun, 1990 Oct, 58(10), 3394 - 400
Protective immunization against experimental Bacteroides (Porphyromonas) gingivalis infection; Chen PB et al.; The effects of immunization in modulating the pathogenesis of Bacteroides (Porphyromonas) gingivalis infection in a murine model system were examined . BALB/c mice were immunized by intraperitoneal injection with B . gingivalis ATCC 53977 (one injection per week for 3 weeks), or with a lithium diiodosalicylate (LIS) extract (one injection per week for 3 weeks), or with lipopolysaccharide (LPS; one intravenous or intraperitoneal injection) from this same strain . Two weeks after the final immunization, the mice were challenged by subcutaneous injection of B . gingivalis ATCC 53977 . Mice immunized with bacteria had no secondary lesions and no septicemia, whereas mice immunized with LIS extract had few secondary lesions and no septicemia . Mice immunized with LPS and nonimmunized mice demonstrated secondary abdominal lesions and septicemia after challenge . Bacterial cells and LIS extract, but not LPS, induced serum antibody and antigen reactive lymphocytes, as measured by enzyme-linked immunosorbent assay, immunoblot, Western immunoblot transfer, and in vitro lymphoproliferative responses . The present study suggests that immunization with a LIS extract or whole cells may induce a protective response against experimental B . gingivalis infection.

Antimicrob Agents Chemother, 1990 Oct, 34(10), 1921 - 4
Pharmacokinetics and tissue penetration of a single dose of ornidazole (1,000 milligrams intravenously) for antibiotic prophylaxis in colorectal surgery; Martin C et al.; Levels in serum and tissue penetration of ornidazole were studied after a single intravenous injection of 1,000 mg given to 14 patients for prophylaxis of surgical infection . They were scheduled for elective colorectal surgery . Adequate levels in blood (greater than or equal to MIC for 90% of Bacteroides fragilis strains tested) were found in all patients throughout the procedure and up to hour 24 . Mean-maximal (15 min) and last-determined (24 h) ornidazole levels in serum were 24 +/- 5.2 and 6.3 +/- 1.4 mg/liter, respectively . beta-Phase elimination half-life was 14.1 +/- 2.7 h, and clearance and apparent volume of distribution were 47 +/- 12 ml/min and 0.9 +/- 0.13 liters/kg, respectively . In all patient, adequate levels in tissue were found in the abdominal wall and the epiploic fat at time of incision and in the colonic wall at time of anastomosis . At time of closure, all but one patient had adequate levels in tissue in the abdominal wall and the epiploic fat . No anaerobic nor aerobic infection occurred in the study patients.

J R Soc Med, 1990 Oct, 83(10), 625 - 6
Use of bacteriology in anorectal sepsis as an indicator of anal fistula: experience in a distinct general hospital; Nicholls G et al.; The bacteriology of anorectal sepsis in a district general hospital has been reviewed to see whether the information gained helped patient management . Forty-six patients with anorectal sepsis were reviewed, underlying fistulas were identified in nine patients (19.5%) . Bacteroides species were not routinely subtyped in the department . It was found that isolation of unspecified Bacteroides species was not helpful in identifying those patients with underlying fistulas . Unless subtyping of Bacteroides species is specifically requested, pus from anorectal sepsis should not routinely be sent for bacteriology.

Appl Environ Microbiol, 1990 Oct, 56(10), 3170 - 3
Application of direct plaque assay for detection and enumeration of bacteriophages of Bacteroides fragilis from contaminated-water samples; Cornax R et al.; The direct double-agar-layer plaque assay for the detection and enumeration of specific bacteriophages of Bacteroides fragilis from contaminated-water samples was performed . Several factors that affect the methods, such as conditions of the bacterial culture, composition of the assay medium, addition of divalent cations, and decontamination techniques applied to the sample, were evaluated . The results obtained show that the direct assay technique proved to be more efficient than the most-probable-number technique . A higher recovery of bacteriophages was obtained from 17 of 24 samples with the direct assay . The two methods only showed similar results from samples with a low degree of pollution.

J Dairy Sci, 1990 Oct, 73(10), 3013 - 22
Physiology and genetics of xylan degradation by gastrointestinal tract bacteria; Hespell RB et al.; Hemicelluloses or xylans are major components (35%) of plant materials . For ruminant animals, about 50% of the dietary xylans are degraded, but only small amounts of xylans are degraded in the lower gut of nonruminant animals and humans . In the rumen, the major xylanolytic species are Butyrivibrio fibrisolvens and Bacteroides ruminicola . In the human colon, Bacteroides ovatus and Bacteroides fragilis subspecies "a" are major xylanolytic bacteria . Xylans are chemically complex, and their degradation requires multiple enzymes . Expression of these enzymes by gut bacteria varies greatly among species . Butyrivibrio fibrisolvens makes extracellular xylanases but Bacteroides species have cell-bound xylanase activity . Biochemical characterization of xylanolytic enzymes from gut bacteria has not been done . A xylosidase gene has been cloned from B . fibrosolvens 113 . The data from DNA hybridizations using a xylanase gene cloned from B . fibrisolvens 49 indicate this gene may be present in other B . fibrisolvens strains . A cloned xylanase from Bact . ruminicola was transferred to and highly expressed in Bact . fragilis and Bact . uniformis . Arabinosidase and xylosidase genes from Bact . ovatus have been cloned and both activities appear to be catalyzed by a single, bifunctional, novel enzyme . Continued research in genetic and biochemical areas will provide knowledge and insights for manipulation of digestion at the gut level and improved understanding of colonic fiber digestion.

FEMS Microbiol Lett, 1990 Oct, 60(1-2), 69 - 73
Interaction of extracellular vesicles of Bacteroides gingivalis W50 with human polymorphonuclear leucocytes; Kay HM et al.; The effects of B . gingivalis W50 extracellular vesicles (ECV) on neutrophil chemotaxis and viability were assessed and compared with those of whole cells and the extracellular non-dialysable soluble protein (EP) fraction . None of the fractions tested, including soluble fractions derived from cells and ECV by sonication, induced neutrophil chemotaxis . Only ECV and cells inhibited f-MLP-stimulated chemotaxis . ECV and cells were cytotoxic towards neutrophils . The cytotoxic response was time dependent . The soluble EP fraction did not influence cell viability.

Int J Syst Bacteriol, 1990 Oct, 40(4), 426 - 33
Transfer of Kingella indologenes (Snell and Lapage 1976) to the genus Suttonella gen . nov . as Suttonella indologenes comb . nov.; transfer of Bacteroides nodosus (Beveridge 1941) to the genus Dichelobacter gen . nov . as Dichelobacter nodosus comb . nov.; and assignment of the genera Cardiobacterium, Dichelobacter, and Suttonella to Cardiobacteriaceae fam . nov . in the gamma division of Proteobacteria on the basis of 16S rRNA sequence comparisons; Dewhirst FE et al.; The 16S rRNA sequences of Kingella indologenes, Cardiobacterium hominis, and Bacteroides nodosus were determined by direct RNA sequencing, using a modified Sanger method . Sequence comparisons indicated that these three species represent a novel family in the gamma division of Proteobacteria . On the basis of these data, K . indologenes and B . nodosus cannot retain their current generic status as they are not closely related to other members of their assigned genera . Therefore, we propose transfer of K . indologenes to the new genus Suttonella as Suttonella indologenes and transfer of B . nodosus to the new genus Dichelobacter as Dichelobacter nodosus and assign the genera Cardiobacterium, Suttonella, and Dichelobacter to a new family, Cardiobacteriaceae, in the gamma division of Proteobacteria.

J Antibiot (Tokyo), 1990 Oct, 43(10), 1302 - 6
R-plasmid mediated transfer of beta-lactam resistance in Bacteroides fragilis; Yamaoka K et al.; We described plasmid mediated transfer of resistance to beta-lactam antibiotics between Bacteroides fragilis strains . Ampicillin-resistance was transferred from B . fragilis strain GAI-10150 to a B . fragilis strain JC-101 with a frequency of 10(-6)/input donor by a filter mating technique . A common plasmid band, named pBFKW1, was found in both the donor and the transconjugants . The plasmid was purified by an ethidium bromide-CsCl ultracentrifugation . The molecular size of the plasmid pBFKW1 which seemed to encode the beta-lactam resistance and beta-lactamase production was estimated ca . 40 kb by the analysis of endonuclease digest . Substrate profile of the enzymes derived from the donor and a transconjugant were of cephalosporinase character.

Can J Microbiol, 1990 Oct, 36(10), 690 - 6
Molecular size variation of the hemagglutinating adhesin HA-Ag2, a common antigen of Bacteroides gingivalis; Chandad F et al.; The array of Bacteroides gingivalis W83 antigens revealed by crossed immunoelectrophoresis includes one antigen that is associated with an erythrocyte-binding capacity, termed the hemagglutinating adhesin HA-Ag2 . This antigen was excised from crossed-immunoelectrophoresis plates to produce two polyclonal antisera, VL 011 and WL 303, whose restricted specificity for HA-Ag2 was assessed using crossed immunoelectrophoresis, crossed immunoelectrophoresis with an intermediate gel, and crossed immunoaffinoelectrophoresis . Both antisera, when used to probe blots of an EDTA cell surface extract of B . gingivalis W83, reacted with two bands, at 33 and 38 kDa, which were also detected by a monoclonal antibody (Naito et al . 1985 . Infect . Immun . 50: 231-235), specific for a hemagglutinin of B . gingivalis . Antiserum WL 303 was used to examined by immunoblotting the distribution of HA-Ag2 among a variety of human and animal strains of B . gingivalis . All human strains tested showed two major bands at 33 and 38 kDa in the EDTA cell surface extract, and at 43 and 49 kDa in outer membrane preparations . Only one band, at 29 kDa, was detected in EDTA cell surface extracts from the animal strains, while the outer membrane preparation of a single strain showed a positive reaction . We concluded that HA-Ag2 is an antigen common to human and animal strains of B . gingivalis and that its subunits may show heterogeneity in apparent molecular mass.

J Clin Periodontol, 1990 Oct, 17(9), 659 - 62
Actinobacillus actinomycetemcomitans and Bacteroides intermedius in human periodontitis: age relationship and mutual association; Slots J et al.; This study examined age relationships and mutual interrelationships between cultivable Actinobacillus actinomycetemcomitans and Bacteroides intermedius in 1624 periodontitis patients, 15 to 89 years of age . Each subject contributed a pooled subgingival sample, obtained from 3 deep periodontal pockets with paper points . A . actinomycetemcomitans occurred with higher prevalence (74%) and mean recovery (7% in culture-positive patients) in patients less than 25 years old than in adult and geriatric patients (prevalence about 31%; mean recovery about 1%) . The organism was detected in 85% of localized juvenile periodontitis patients . B . intermedius was recovered from 45% of the study subjects, averaged about 7% of total isolates in positive patients, and showed no predilection for any age group . As determined from predicted and observed values for A . actinomycetemcomitans and B . intermedius, occurring alone and in combination, no synergistic or antagonistic relationships between the organisms could be delineated with respect to subgingival colonization . The therapeutic implication of these findings is discussed.

J Clin Microbiol, 1990 Oct, 28(10), 2269 - 74
Biochemical and serological characterization of Bacteroides intermedius strains isolated from the deep periodontal pocket; Dahlen G et al.; Fifty-one fluorescence-positive black-pigmented Bacteroides strains obtained from 51 patients with deep periodontal pockets (greater than 6 mm) were identified and characterized . Fifty of these strains were presumptively identified as Bacteroides intermedius according to the indole reaction . This was confirmed by further biochemical characterization . The 50 strains from diseased sites were then compared with 16 B . intermedius strains isolated from periodontally healthy individuals with no signs of destructive periodontal disease . Tests for antimicrobial susceptibility showed similar patterns for all 50 pocket-derived strains, except for one beta-lactamase-positive strain that was resistant to penicillin G and ampicillin . Forty-seven strains were tested for binding of three monoclonal antibodies defining three distinct serogroups of B . intermedius . Thirty-one strains belonged to serogroup I, three to serogroup II and thirteen to serogroup III . In comparison to the strains from the shallow periodontal pockets, serogroup I was significantly overrepresented in the patient group with periodontal disease . We conclude that saccharolytic black-pigmented Bacteroides species from deep periodontal pockets constituted, with very rare exceptions, a biochemically homogeneous but antigenically heterogeneous group of B . intermedius and that serogroup I is predominantly found in deep periodontal lesions.

J Clin Microbiol, 1990 Oct, 28(10), 2248 - 52
Application of monoclonal antibodies to the detection of black-pigmented Bacteroides spp . in subgingival plaques by immunoslot blot assay; Hanazawa S et al.; The aim of the present study was to assess the application of monoclonal antibodies to the detection of black-pigmented Bacteroides spp . in subgingival plaques by immunoslot blot assay . Subgingival plaque samples from adult periodontal patients were examined by immunoslot blot assay with monoclonal antibodies that specifically recognize Bacteroides gingivalis, Bacteroides intermedius serogroups I and II, and Bacteroides melaninogenicus . The assay can detect specifically these Bacteroides spp . in the subgingival plaques . Therefore, we investigated the distribution of these Bacteroides spp . in the subgingival plaques of patients classified by Russell's periodontal index . Reactivities of their plaques with monoclonal antibodies toward B . gingivalis and B . intermedius serogroup I were clearly related to the severity of the periodontal disease, but this was not the case with B . intermedius serogroup II and B . melaninogenicus . These results indicate that this immunoslot blot assay using monoclonal antibodies toward these Bacteroides spp . provides simple detection and monitoring of these organisms in periodontal patients.

J Clin Microbiol, 1990 Oct, 28(10), 2220 - 3
Short prereduced anaerobically sterilized (PRAS) biochemical scheme for identification of clinical isolates of bile-resistant Bacteroides species; Citron DM et al.; The rapid identification of isolates of bile-resistant Bacteroides species has clinical and therapeutic relevance because of differences in their patterns of susceptibility and virulence . Five hundred twenty-one strains of bile-resistant Bacteroides species that were previously identified by conventional biochemical methods were reexamined to determine the minimum essential parameters necessary for correct identification . Rapid tests for bile resistance, indole production, and catalase were combined with a novel scheme for biochemical determination of saccharolytic activity on arabinose, trehalose, rhamnose, and/or xylan that included the postincubation addition of bromthymol blue for visual pH determination . Organisms were inoculated into prereduced anaerobically sterilized (PRAS) carbohydrates directly from plates, and identification was complete within 24 h of obtaining a pure culture . Ninety-three percent of bile-resistant Bacteroides species from routine clinical specimens were identified correctly by this scheme; a small number of other indole-positive strains, B . splanchnicus, B . eggerthii, and B . stercoris, were misidentified as B . uniformis.

J Dent Res, 1990 Oct, 69(10), 1696 - 702
The utility of the BANA test for monitoring anaerobic infections due to spirochetes (Treponema denticola) in periodontal disease; Loesche WJ et al.; Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus each possesses an enzyme(s) that hydrolyzes the synthetic substrate benzoyl-DL-arginine-naphthylamide (BANA) . The presence of these organisms in a subgingival plaque sample can be determined by the ability of the plaque to hydrolyze BANA . In the present study, we describe the usefulness of the BANA test at various stages of a clinical trial of the efficacy of metronidazole in the treatment of periodontal disease . A BANA-positive test was significantly associated with high levels and proportions of spirochetes in the plaque, so that it provided information comparable with that which could be obtained by a microscopic examination of the plaque . Patients with such anaerobic spirochetal infections were randomly assigned to a group receiving either metronidazole or placebo (250 mg, three times a day) for one week and whose teeth were scaled and root-planed . The advantages of the decision that metronidazole be used were apparent from the comparison with the results obtained in the patients who received only the scaling and root planing . The initially BANA-positive teeth in the patients treated with metronidazole, scaling, and root planing gained attachment and exhibited a significant reduction in the need for periodontal surgery, when compared with the BANA-positive teeth in the patients who received only placebo, scaling, and root planing . After the conclusion of this therapy, those teeth with persistent BANA-positive plaques had significantly higher proportions and levels of spirochetes than did the teeth with BANA-negative plaques.(ABSTRACT TRUNCATED AT 250 WORDS)

Hosp Pract (Off Ed), 1990 Oct, 25 Suppl 4, 24 - 30
Effects of differences in media and methods on MIC values for anaerobes; Wexler HM et al.; In vitro susceptibility of Bacteroides fragilis isolates to cefoxitin at the breakpoint of 32 micrograms/ml varied little when tested by eight different methods . We found that broth disk elution results were difficult to read and interpret and did not correlate with other methods.

Hosp Pract (Off Ed), 1990 Oct, 25 Suppl 4, 20 - 3
Intra-abdominal abscess in children: a 13-year experience; Brook I; The microbiology of intra-abdominal abscess in children is similar to that of adults--a mixture of aerobes and anaerobes . In abscess specimens taken from 36 children, predominant pathogens were Bacteroides fragilis group species, Peptostreptococcus species, and Escherichia coli.

Oral Microbiol Immunol, 1990 Oct, 5(5), 302 - 4
Immunoreactivity in humans of Bacteroides gingivalis hemagglutinating adhesin HA-Ag2; Deslauriers M et al.; A rabbit antiserum monospecific for HA-Ag2, a hemagglutinating adhesin of Bacteroides gingivalis, was used as a reference to screen sera from 8 patients with chronic periodontitis and 6 normal subjects for specific antibodies . The monospecific antiserum detected a complex of 2 polypeptides with molecular weights of 43 and 49 kDa in an outer membrane preparation of B . gingivalis . All human sera reacted with one or both polypeptides in at least one of the isotypes (IgG, IgA and IgM) tested, indicating that HA-Ag2 is an immunodominant antigen . Although the 2 components of HA-Ag2 are antigenically similar, a trend toward preferential reactivity of IgM with the 49 kDa component was observed . This suggests that an epitope-specific mechanism of regulation of the immune response to B . gingivalis in humans may exist via the HA-Ag2 complex.

Oral Microbiol Immunol, 1990 Oct, 5(5), 275 - 9
Benzoyl-arginine naphthylamide (BANA) hydrolysis by Treponema denticola and/or Bacteroides gingivalis in periodontal plaques; Bretz WA et al.; Treponema denticola and Bacteroides gingivalis are among the few recognized species found in periodontal pockets that can hydrolyze the synthetic peptide N-benzoyl-DL-arginine-2-naphthylamide (BANA) . We determined the presence of these periodontal pathogens in BANA-positive and -negative plaque samples through the use of indirect immunofluorescent antibody techniques . Eighteen of 27 diseased sites gave BANA-positive reactions, and 9 gave BANA-negative reactions . T . denticola was present in 16 of 18 BANA-positive reactions, whereas B . gingivalis was detected in 9 of the 18 BANA-positive reactions . T . denticola was present in 1 and B . gingivalis in 2 of the 9 BANA-negative reactions . Neither organism was detected in the 19 healthy sites that were negative for BANA . All measured differences between BANA-positive and BANA-negative plaques obtained in the same individuals were statistically significant . The accuracy of the BANA test, compared with clinical parameters such as bleeding upon probing and increased probing depth, was about 80% . The accuracy of the test in detecting the presence of T . denticola was 93%, for B . gingivalis, 76% and for T . denticola and/or B . gingivalis, 96% . This study indicated that BANA-positive plaques were associated with the presence of T . denticola and/or B . gingivalis, that T . denticola was found at a greater frequency and levels in BANA-positive plaques than B . gingivalis, and that the presence of these organisms was associated with clinical disease.

Oral Microbiol Immunol, 1990 Oct, 5(5), 269 - 74
Haemagglutinating and haemolytic activity of the extracellular vesicles of Bacteroides gingivalis W50; Kay HM et al.; The extracellular vesicles (ECV) and extracellular protein (EP) fractions of Bacteroides gingivalis W50 showed haemagglutinating (HA) activity towards sheep erythrocytes . Similar fractions from the nonpathogenic strain W50/BE1 did not haemagglutinate . W50 ECV HA activity was not inhibited by various glycosidase, phospholipase or protease pretreatments, sugars or amino acids, including arginine or lysine . The haemagglutinating activity of ECV was associated only with the extracellular vesicle membrane . The EP and ECV of both strains displayed haemolytic activity . This activity was apparently depressed in the presence of 10 mM dithiothreitol (DTT) . All EP and ECV fractions degraded certain structural sheep erythrocyte membrane proteins . The greatest activity was displayed by W50 ECV and W50/BE1 EP and was enhanced by DTT . In the presence of DTT, the ECV of both strains degraded purified human haemoglobin but this activity was greatly reduced in its absence.

Oral Microbiol Immunol, 1990 Oct, 5(5), 263 - 8
Effect of iron limitation on Bacteroides gingivalis; Barua PK et al.; This study was undertaken to describe the effects of iron limitation on Bacteroides gingivalis . Four strains of B . gingivalis were grown in brain heart infusion broth, substituting protoporphyrin IX for hemin . Culture with protoporphyrin IX resulted in a loss of a 28 kDa membrane protein, but no decrease in growth . Iron-restricted cultural conditions for the growth of B . gingivalis were achieved using alpha/alpha'-dipyridyl, a ferrous iron chelator, at concentrations from 12.5 microM to 300 microM . Total suppression of bacterial growth for strain A7A1-28 and strain 381 was achieved at 200 microM alpha/alpha'-dipyridyl . At 300 microM alpha/alpha'-dipyridyl, strain W50 and Bowden 18/10 showed 100% and 80% suppression of growth, respectively . The ferric iron chelator Desferal did not show suppression of growth in concentrations up to 500 microM . The dipyridyl inhibition of cell growth for strain A7A1-28 could be reversed by adding excess ferrous ammonium sulphate but not by ferric nitrate . Iron regulation of proteolytic enzymes could not be demonstrated . Two new membrane proteins 42 kDa and 24 kDa are expressed with iron limitation, and the 45 kDa membrane protein was decreased with iron limitation.

Oral Microbiol Immunol, 1990 Oct, 5(5), 248 - 55
Interaction of gram-negative periodontal pathogens with retinoic acid-induced and dimethyl sulfoxide-induced HL-60 cells; Armitage GC et al.; As a first step toward elucidating the reasons for differences among periodontal pathogens in their cytotoxic effects on HL-60 cells, we used transmission electron microscopy to examine morphological aspects of granulocyte-bacteria interactions . Unopsonized Actinobacillus actinomycetemcomitans strain Y4 and Bacteroides gingivalis ATCC 33277 adhered to, and were phagocytosed by, retinoic acid-induced and dimethyl sulfoxide-induced HL-60 cells . In contrast, there was only minimal interaction between Wolinella recta ATCC 33238 and these induced granulocyte-like cells . Only isolated examples of adherence of W . recta to HL-60 cells were seen . In specimens prepared for routine transmission electron microscopy, ingested W . recta were not observed . In immunogold experiments, phagocytosed W . recta were noted, but only rarely . Opsonization of A . actinomycetemcomitans, B . gingivalis and W . recta with specific antisera appeared to increase their level of interaction with the HL-60 cells . We suggest that the HL-60 cell line may be useful in elucidating structure-function relationships between human neutrophil-like cells and putative periodontopathogens.

Oral Microbiol Immunol, 1990 Oct, 5(5), 241 - 7
Effect of Actinobacillus actinomycetemcomitans, Wolinella recta and Bacteroides gingivalis on the viability of retinoic acid-induced and dimethyl sulfoxide-induced HL-60 cells; Armitage GC et al.; We studied the interactions between viable and heat-killed, opsonized and unopsonized periodontopathic bacteria with both uninduced and induced HL-60 promyelocytic leukemia cells . The cells were induced to differentiate into granulocyte-like cells by incubation with retinoic acid (RA) or dimethyl sulfoxide (DMSO) . When unopsonized, Wolinella recta ATCC 33228 significantly suppressed the net proliferation of uninduced HL-60 cells, Actinobacillus actinomycetemcomitans strain Y4 was markedly lethal to the cells, and Bacteroides gingivalis ATCC 33277 had no effect . Unopsonized and opsonized A . actinomycetemcomitans and W . recta had equally potent lethal effects on induced HL-60 cells . Unopsonized B . gingivalis was not lethal to the induced cells in the dose used (100 bacteria/HL-60 cell), but opsonized B . gingivalis was lethal, especially in the first 24 h . The killing effects of A . actinomycetemcomitans and W . recta were largely eliminated if they were heated (56 degrees C, 30 min) before being added to the induced HL-60 cells . RA-induced HL-60 cells were more sensitive to the lethal effects of A . actinomycetemcomitans and W . recta than were DMSO-induced cells . The results suggest that the HL-60 cell line may be a useful model for studying granulocyte-bacteria interactions.

Microbiologica, 1990 Oct, 13(4), 333 - 7
A simple technique useful for clinical laboratory testing for invasive potential applied to Bacteroides fragilis; Goldner M et al.; A simple technique using fluorescent microscopy examines the association between Bacteroides fragilis and different types of tissue cells (epithelial, fibroblast, osteoblast) . Through this stepwise intracellular staining and extracellular quenching some latent signs of invasive quality may be exhibited . The bacteria are incubated with monolayers of tissue cells, and the reactions immediately visualized after staining with acridine orange and masking by crystal violet . Intact bacterial rods exhibit a greenish hue which will reveal their location within the tissue cells but varies depending on tissue cell type . This direct means of testing for invasive potential applied to B . fragilis relies on the use of a readily available clinical tool.

FEMS Microbiol Lett, 1990 Sep 1, 59(1-2), 5 - 9
Characterisation of Bacteroides from sheep periodontal disease by SDS-PAGE of outer membrane proteins; McCourtie J et al.; Isolates of Bacteroides species obtained from a longitudinal study of developing periodontal disease in sheep were analysed by SDS-PAGE . Protein profiles of Sarkosyl-insoluble outer membrane extracts were compared within groups of isolates which had already been defined by conventional biochemical techniques . Heterogeneity was exhibited within most groups . Isolates of B . gingivalis and B . asaccharolyticus shown to be similar to human isolates by conventional biochemical tests, gave different protein profiles from the respective type cultures . The sheep B . gingivalis-like isolates were however homogeneous, while the B . asaccharolyticus-like organisms could be divided into 3 subgroups . SDS-PAGE appears to be a useful tool for the examination of bacterial flora and recognition of subgroups of subspecies.

FEMS Microbiol Lett, 1990 Sep 1, 59(1-2), 187 - 92
Role of neuraminidase-dependent adherence in Bacteroides fragilis attachment to human epithelial cells; Guzman CA et al.; Of 50 B . fragilis strains isolated from clinical samples we have demonstrated that 24 (48%) possess an adhesin that mediates a neuraminidase-dependent attachment of B . fragilis to mammalian epithelial cells, but does not mediate any association with human polymorphonuclear leucocytes . This ligand interacts with a mammalian cell receptor that contains a galactoside residue, exposed after neuraminidase pretreatment . Our results suggest a possible role for cell associated neuraminidase in mediating a two step adherence mechanism.

FEMS Microbiol Lett, 1990 Sep 1, 59(1-2), 1 - 4
Outer membrane proteins of Bacteroides fragilis grown in vivo; Patrick S et al.; The outer membrane protein (OMP) profiles of four different strains of Bacteroides fragilis, as determined by Coomassie blue stained polyacrylamide gels, were compared after growth in broth culture and in the mouse peritoneal cavity . There was no induction of the expression of large quantities of novel OMP after growth in vivo . Mouse immunoglobulin G and albumin were associated with the bacterial OMP, but could be removed by washing.

J Oral Pathol Med, 1990 Sep, 19(8), 360 - 6
Cytotoxic and immunostimulatory effects of Bacteroides cell products; Fotos PG et al.; The etiologic role of Bacteroides in both periodontal and periapical infections has been well documented, with current interest focusing on the specific pathogenic mechanisms involved . The effects of cell fractions derived from Bacteroides gingivalis (BG), Bacteroides intermedius (BI), and Bacteroides asaccharolyticus (BA) have been studied in vitro through: an assessment of the direct cytotoxic effects on human gingival fibroblasts using a tetrazolium dye reduction assay, an evaluation of murine lymphocyte stimulation and interleukin-1 release, and the induction of human lymphocyte-mediated cytotoxicity . Both BG and BI stimulated interleukin-1 release (P less than 0.001), while BA, a nonoral organism, was not significantly active in this respect . Only BG sonicates were able to induce lymphocyte-mediated cytotoxicity (P less than 0.005) . All three Bacteroides species demonstrated direct cytotoxic effects on cultured gingival fibroblasts, and these effects were related to the relative protein content and endotoxin activity of the sonicate preparations for each organism . These data show that BG and BI possess factors which may enhance their virulence through activities not shared with BA.

Can J Microbiol, 1990 Sep, 36(9), 637 - 48
Study of the antigenic relationships between strains of Bacteroides, intermedius, B . melaninogenicus, B . corporis, and B . denticola revealed by immunoblotting with rabbit antisera; Bowden GH et al.; Antigen profiles of saccharolytic oral black-pigmented Bacteroides have been developed by Western blotting . Visual comparisons indicated extensive cross-reactions between B . intermedius, B . melaninogenicus, B . denticola, and B . corporis . Porphyromonas gingivalis, P . asaccharolyticus, and B . buccae showed less cross-reaction . Quantitation of antigenic similarity was made from densitometric scans . Calculation of the Jackard coefficient gave results of 33-72% similarity among the saccharolytic pigmented species, with the two homology groups of B . intermedius separated at 53% . Species were separated below 70% . Subtraction of the profile of a cross-reacting strain from that of the homologous strain also allowed quantitation of similarities . These similarities were lower; the range between species was 4-62%, although the two homology groups of B . intermedius still separated at 50 and 58% . Species were separated below 63% . Sera absorbed with a cross-reacting strain gave reduced reactions with the homologous strain and cross-reacting strains, indicating several common antigens among the four species . The species-specific antigens demonstrated by sera absorbed with cells of cross-reacting species were relatively few (3-6) compared with cross-reacting antigens detected by non-absorbed sera (18-28) . The method appears useful to quantitate antigenic similarities among Bacteroides species and strains and allows analysis and quantitation of individual humoral responses in animals to these bacteria.

J Appl Bacteriol, 1990 Sep, 69(3), 421 - 5
Effect of growth conditions and storage on the specific activity of beta-lactamases of Bacteroides spp; Edwards R et al.; The influences of growth conditions and cold storage on the specific activity of beta-lactamases of four strains of Bacteroides spp . was studied . Interbatch variation was observed in extracts prepared in an identical way on separate occasions but less variation was observed in extracts prepared from bacteria grown on Brain Heart Infusion agar supplemented with yeast extract, haemin and menadione, than in similar extracts of bacteria grown in broth or on other solid media . The loss of enzyme activity seen during the stationary phase of growth of some strains in broth was minimal during incubation for 48 h on agar . Storage of enzyme extracts at 4 degrees C was associated with loss of enzyme activity, but activity was retained during storage at -70 degrees C for up to 32 days . Freezing and thawing had little effect on enzyme activity.

Ear Nose Throat J, 1990 Sep, 69(9), 614 - 8
Antagonism among Bacteroides fragilis group strains isolated from middle ear exudates from patients with chronic suppurative otitis media; Rocha ER et al.; The production and sensitivity of a bacteriocin-like substance in Bacteroides fragilis group strains isolated from middle ear exudates in children with suppurative otitis media were studied through antagonism assayed by the well method . The results of the crossed reactions showed that 10 strains (66.6%) were bacteriocinogenic, 9 were sensitive to at least 1 bacteriocin (60%), and none showed inhibitory activity against homologous strains . Different patterns of susceptibility to bacteriocin-like substances were observed among strains isolated from the same patient as well as different strains isolated from another patient . These findings indicate that bacteriocin typing of anaerobic bacteria isolated from middle ear exudates in children with otitis media might have use in epidemiologic studies.

J Med Microbiol, 1990 Sep, 33(1), 29 - 34
Analysis of the porphyrin content of fluorescent pus by absorption spectrophotometry and high performance liquid chromatography; Brazier JS; Extracts of 19 samples of pus which showed red fluorescence with ultraviolet light were screened for the presence of porphyrins by absorption spectrophotometry . All those which showed spectra typical of metal-free porphyrins were analysed by high performance liquid chromatography to identify the porphyrins present . These were predominantly the di-carboxylic porphyrins, deuteroporphyrin and mesoporphyrin, and another which was thought to be pemptoporphyrin . This combination matched those reported previously in normal stools . Protoporphyrin IX was shown not to be the most common fluorescent pigment in pus and was never present alone . However, the di-carboxylic porphyrins may be produced by bacterial metabolism of its labile vinyl side-chains . Black-pigmented bacteroides (the melaninogenicus group of Bacteroides spp . and Porphyromonas spp.) were isolated from 12 (63%) of the 19 pus samples; these may produce protoporphyrin IX by the demetallation of haem.

J Antimicrob Chemother, 1990 Sep, 26(3), 361 - 70
Beta-lactamase production, beta-lactam sensitivity and resistance to synergy with clavulanate of 737 Bacteroides fragilis group organisms from thirty-three US centres; Jacobs MR et al.; Beta-Lactamase production and agar dilution sensitivities to amoxycillin, amoxycillin/clavulanate, ticarcillin, ticarcillin/clavulanate, cefoxitin, imipenem and metronidazole were determined for 737 Bacteroides fragilis group strains isolated between 1986 and 1988 from 33 US centres . The strains comprised 441 B . fragilis, 114 B . thetaiotaomicron, 35 B . ovatus, 58 B . distasonis, 58 B . vulgatus, 26 B . uniformis and five B . caccae . Overall, addition of clavulanate lowered the geometric mean MICs of of amoxycillin from 46.7 to 0.6 mg/l, and of ticarcillin from 37.2 to 1.3 mg/l . Addition of clavulanate increased the number of strains sensitive to amoxycillin from 9.5% to 90.0%, and to ticarcillin from 68.0% to 98.6% . However, synergy was not observed following addition of clavulanate to amoxycillin and ticarcillin for 48 strains (6.5%) . These comprised 15 B . fragilis, two B . ovatus, 21 B . distasonis, six B . vulgatus and four B . uniformis strains . Ten of the 15 non-synergic B . fragilis isolates had the features of B . fragilis homology group II and were susceptible to amoxycillin alone; the other five strains were resistant to amoxycillin and ticarcillin . Geometric mean MICs (% susceptibility) of the non-synergic strains were as follows: amoxycillin, 6.2 mg/l (68.8); amoxycillin/clavulanate, 4.8 mg/l (72.9); ticarcillin, 11.8 mg/l (75.0); ticarcillin/clavulanate, 9.4 mg/l (77.1) . Twenty-six strains (3.5% were resistant (greater than 32 mg/l) to cefoxitin, and two strains (0.3%) were resistant (4 mg/l) to imipenem . All were susceptible to metronidazole . Thus, on the basis of in-vitro activity, metronidazole, imipenem, ticarcillin/clavulanate, cefoxitin and amoxycillin/clavulanate are indicated for treatment of infections with B . fragilis strains . The clinical significance of the lack of synergy with clavulanate in the B . fragilis group is unclear; relatively low beta-lactam MICs for most of these strains suggests that they may be amenable to therapy with high doses of beta-lactams . Results of this study indicate that it cannot be assumed that clavulanate will uniformly inhibit beta-lactamases in the B . fragilis group (especially B . distasonis) and indicate the need for identification and susceptibility testing, especially in cases of serious infections with these strains.

J Antimicrob Chemother, 1990 Sep, 26(3), 353 - 9
In-vitro study of the susceptibility of cefoxitin/cefotetan resistant Bacteroides fragilis group strains to various other antimicrobial agents; Aldridge KE et al.; The in-vitro activity of various beta-lactam antibiotics, beta-lactam/beta-lactamase inhibitor combinations, clindamycin, and metronidazole was determined against Bacteroides fragilis group isolates that were resistant to both cefoxitin and cefotetan . Among the cephalosporins tested ceftizoxime was the most active with 80% of the strains susceptible, followed by cefotaxime (65% susceptible), and cefoperazone (47% susceptible) . Piperacillin and clindamycin showed comparable activity to ceftizoxime with 80% and 81% susceptible, respectively . The addition of a beta-lactamase inhibitor (sulbactam, clavulanate, or tazobactam) enhanced the activity of the various beta-lactam agents from 4-fold to 16-fold overall . One strain of B . fragilis was found that was resistant to all beta-lactam agents either alone or in combination . All strains in this study were susceptible to less than or equal to 4 mg/l of metronidazole.

Br Vet J, 1990 Sep-Oct, 146(5), 437 - 42
In-vitro antimicrobial susceptibility of Bacteroides and Fusobacterium isolated from footrot in goats; Piriz Duran S et al.; The agar dilution method was used to determine the antimicrobial activity of 17 antimicrobial agents against 132 strains belonging to the genus Bacteroides and 25 strains from the genus Fusobacterium, all isolated from 120 clinical cases of caprine footrot between October 1987 and November 1988 . Josamycin, chloramphenicol and rifampin proved to be the most effective antibiotics in vitro . Significant resistance was found to the other antimicrobial agents studied.

J Clin Periodontol, 1990 Sep, 17(8), 533 - 41
Plaque and chronic inflammatory periodontal disease . A question of ecology; Newman HN; The nature of the relationship between dental plaque and chronic inflammatory periodontal disease (CIPD) remains unclear, although there is no doubt that plaque is the direct cause . Non-specific, specific and exogenous hypotheses have been proposed to explain plaque-host relationships . Current evidence indicates that plaque is part of the natural human microflora, one of many such in nature, and that disruption of oral microbial ecology, due primarily to diet texture changes, leads to gingivitis and periodontitis . These result in increased plaque accumulation, and particularly in increased interdental effective plaque thickness . The latter leads to alterations in plaque ecology, particularly increasing anaerobiosis, with resultant shifts in proportions of its constituent species . These shifts are responsible for the increased counts of, for example, Bacteroides gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Wolinella recta, spirochaetes and others, associated with chronic periodontitis in its various forms . Measures to prevent or control chronic periodontitis should aim, not to eliminate plaque, which ignores ecology and would compromise host defence, but to restore the species distribution in plaque to that compatible with health.

Antimicrob Agents Chemother, 1990 Sep, 34(9), 1858 - 61
Comparative in vitro activities of a new quinolone, WIN 57273, and piperacillin plus tazobactam against anaerobic bacteria; Venezia RA et al.; The in vitro activities of a new quinolone, WIN 57273, and the combination of piperacillin and tazobactam, a beta-lactamase inhibitor, were compared with those of cefoxitin, ceftizoxime, chloramphenicol, clindamycin, imipenem, metronidazole, and piperacillin for 123 clinical anaerobic isolates . Ceftizoxime and cefoxitin had equivalent activities, while metronidazole was active against gram-negative isolates . In the Bacteroides fragilis group, species other than B . fragilis were the most resistant . The combination of piperacillin with tazobactam in a ratio of 8 to 1 was more effective than piperacillin against B . fragilis group organisms when the MIC of piperacillin was greater than or equal to 64 micrograms/ml . Overall, WIN 57273 (i) and imipenem (ii) were the most active agents, with MICs for 50 and 90% of strains of (i) 0.25 and 0.5 and (ii) 0.125 and 2 microgram/ml, respectively.

Diagn Microbiol Infect Dis, 1990 Sep-Oct, 13(5), 371 - 3
Antimicrobial spectrum of cefpirome combined with tazobactam against the Bacteroides fragilis group; Jones RN et al.; Cefpirome, a so-called fourth-generation cephalosporin, was tested alone and in combination with the sulfone beta-lactamase inhibitor, tazobactam, against 63 members of the Bacteroides fragilis group . The cefpirome MIC50 was only 64 micrograms/ml, but the MIC was reduced eightfold with tazobactam (2:1 ratio) . The addition of tazobactam to cefpirome or the use of metronidazole as a codrug appear to be alternative choices to enhance the antianaerobic spectrum . Over 98% of strains had cefpirome-tazobactam MICs of less than or equal to 32 micrograms/ml.

Nichidai Koko Kagaku, 1990 Sep, 16(3), 332 - 9
{Mitogenic activity of lipopolysaccharide from Bacteroides intermedius against C3H/HeJ mice spleen cells}; Yamamoto M et al.; Bacteroides intermedius is one of the periodontal disease generative bacteria . Lipopolysaccharide preparation obtained from B . intermedius ATCC 25611 and ATCC 33563 strains was investigated as to Limulus activity observed with Pyrodic (endotoxin specific) reagent, and mitogenic activity in both normal and tolerant mice induced by Escherichia coli . Limulus activities of all LPS's were nearly similar to that of E . coli . LPS's preparation from B . intermedius were found to be strongly mitogenic for C3H/HeN mice spleen cells, whereas no LPS preparations were mitogenic for thymocytes of BALB/c mice . LPS-nonresponsive C3H/HeJ mice spleen cells were found to good mitogenic responses to LPS's from B . intermedius, as well as LPS from B . gingivalis 381 strain . Polymyxin B had remarkable inhibitory effect on the mitogenicity of LPS's from B . intermedius for C3H/HeN and C3H/HeJ mice spleen cells, also that activity of B . gingivalis LPS was inhibited by polymyxin B . The mitogenicity of the LPS from B . intermedius, as measured in C3H/HeJ mice spleen cells, was considerably resistant to the proteolytic effects of proteinase K.

Infect Immun, 1990 Sep, 58(9), 2882 - 7
Purification and characterization of alkaline phosphatase of Bacteroides gingivalis 381; Yamashita Y et al.; Cell-associated alkaline phosphatase (ALPase) of Bacteroides gingivalis 381 was found in the outer part of the periplasmic space by using an ultracytochemical procedure . Cell-associated ALPase was solubilized by extraction with 1% Triton X-100, and the solubilized enzyme was purified 904-fold with 5.6% recovery by using affinity column chromatography for mammalian intestinal-form ALPase . The purified enzyme gave a single protein band that corresponded to the enzyme activity band on polyacrylamide gel electrophoresis preparations . A single protein band at a molecular weight of 61,000 was observed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis preparations . The molecular weight of the native enzyme was estimated to be 130,000 by gel filtration with TSK-gel G3000SW . These findings indicate that B . gingivalis ALPase is a homodimer . The optimal pH of the enzyme was between 9.1 and 9.3 in the absence of divalent metal ions and was between 10.1 and 10.3 in the presence of manganese or zinc ions . The apparent km for p-nitrophenylphosphate was 0.037 +/- 0.003 mM (mean +/- standard deviation) at pH 9.2 in the absence of divalent metal ions and 0.22 +/- 0.02 mM at pH 10.2 in the presence of 1 mM manganese ions . Under both of the conditions described above, the purified enzyme was able to hydrolyze casein and O-phosphoserine, suggesting that B . gingivalis ALPase can act as a phosphoprotein phosphatase . ALPase that immunologically cross-reacted with the purified enzyme was found in the extracellular soluble fraction . This means that ALPase is released from the periplasmic space into the culture supernatant as a soluble form.

Int Endod J, 1990 Sep, 23(5), 254 - 62
Extensive bone loss associated with periapical infection with Bacteroides gingivalis: a case report; Sjogren U et al.; A case is presented in which rapid and extensive bone loss occurred around a maxillary molar with periapical infection by Bacteroides gingivalis (Porphyromonas gingivalis) . The lesion failed to respond to conventional endodontic therapy . An adjacent vital molar was extracted and an unfavourable periodontal condition occurred despite microbiological investigation and surgery.

Plasmid, 1990 Sep, 24(2), 100 - 9
Plasmid transformation of Bacteroides spp . by electroporation; Smith CJ et al.; Transformation of Bacteroides spp . with a variety of plasmid DNAs was accomplished using electroporation . The standard transformation assay system used to deduce the optimal electroporation parameters employed a 50-to 100-fold concentrated cell suspension of mid-logarithmic phase Bacteroides fragilis strain 638 and the 5.4-kb clindamycin resistance (Ccr) vector, pBI191 . A variety of electroporation buffers were used successfully in transformation experiments but of these, 1 mM MgCl2 in 10% glycerol was superior . The incorporation of MgCl2 was essential for optimum viability prior to electroporation and for optimum transformation . Transformants were routinely obtained using 5-ms pulses over a range of field strengths from 5 to 12.5 kV/cm, with a maximum of greater than 10(6) micrograms-1 DNA at 12.5 kV/cm . The number of transformants increased linearly with respect to DNA concentration over the range 0.01-2 micrograms tested . Recovery of transformants required an expression period of up to 2.5 h following exposure to the electric field . This period, however, was dependent on the antibiotic resistance marker used for selection of transformants, with a significantly shorter incubation required when chloramphenicol rather than clindamycin was used in the selective medium . The effect of the DNA source on transformation was tested using the shuttle vector pFD288 . Plasmid DNA isolated from Bacteroides uniformis, Bacteroides ovatus, or Bacteroides thetaiotaomicron transformed B . fragilis 638 at frequencies 7.5- to 12.5-fold less than those observed for controls with homologous DNA . Further reductions were seen with Escherichia coli purified pFD288, which transformed at 1000-fold lower frequencies . Finally, using homologous pFD288 or pBI191 isolated from strain 638, several strains of B . fragilis, B . uniformis, and B . ovatus were transformed successfully without modification of the standard assay system . Two strains each of B . thetaiotaomicron and Bacteroides ruminicola were not transformed using the methods described here.

J Pharm Belg, 1990 Sep-Oct, 45(5), 311 - 8
A collaborative study of French laboratories to assess any evolution of antibiotic resistance within the Bacteroides fragilis group; Dubreuil L et al.; Antibiotic susceptibility testing of anaerobes by a same methodology allows the authors to draw up suggestions about the evolution of antibiotic resistance within the B . fragilis group . Cefoxitin resistance rates were stable until 1985 and were slowly increasing later . Until 1985 piperacillin was able to inhibit all tested strains . In 1987 the two groups noticed an increasing resistance to piperacillin (4 to 9%) . During the 1970's clindamycin resistance was a minor event (less than 1%) then the resistance rate increased rapidly to 10% in 1980 . MICs determinations from 1981 to 1985 demonstrated well that clindamycin resistance was stable at this 10% rate . Since 1987 the clindamycin resistance was again increasing and reached respectively 14 to 19% for the two groups of investigators . Metronidazole has kept a good activity against Bacteroides fragilis group strains but some strains with reduced susceptibility (MIC 2 to 8 mg/l) have been described since 1983 . Three strains with MIC greater than 8 mg/l were recently described by one of the groups . Until 1987, the clavulanic amoxicillin combination was able to inhibit all strains of the B . fragilis group but only imipenem remained still active on all investigated strains with no change at all for the values of MIC50 and MIC90 determined by the investigators of this study . All these results emphasize the need for periodical surveys within the B . fragilis group in each country.

Infect Immun, 1990 Sep, 58(9), 2785 - 91
Characterization of rat T helper cell clones specific for Bacteroides gingivalis antigen; Katz J et al.; During the past several years, much interest has been directed towards delineating and characterizing different subsets of T helper (Th) cells in order to understand their roles in immune processes . In this study, we report the generation of antigen-specific rat Th cell clones and their characterization in terms of phenotype, function, and lymphokine production . The clones were derived by culturing purified splenic T cells from rats immunized with the pathogen Bacteroides gingivalis with equivalent numbers of irradiated spleen cells from nonimmune rats and B . gingivalis whole-cell antigen . The clones required antigen stimulation but not exogenously added interleukin-2 for growth and were maintained in culture for approximately 6 months . The cloned T cells proliferated in response to the mitogen concanavalin A and to B . gingivalis whole-cell antigen but not to other microbial antigens . Phenotypic characterization of the cloned T cells for cell surface markers demonstrated that these cells were OX19+ W3/25+ OX8- OX22- and therefore probably represented a mature subpopulation of CD4+ Th cells . These cloned T cells were positive for interleukin-2 receptor expression . Culture supernatants from the Th cell clones which were collected at various times after antigen stimulation exhibited low interleukin-2 activity and high gamma interferon activity . This in vitro study provides evidence of a rat Th cell subset that could represent an important population in regulating immune responses to microbial antigens.

Nippon Juigaku Zasshi, 1990 Aug, 52(4), 719 - 25
Distribution of immunoglobulin-containing cells in calves inoculated orally with ruminal Bacteroides succinogenes and Selenomonas ruminantium; Sato S et al.; Distribution of immunoglobulin(Ig)-containing cells was investigated in calves inoculated orally with live organisms of both Bacteroides succinogenes and Selenomonas ruminantium . Pathological changes and many Ig-containing cells were observed in calves which inoculated three times at 2, 3 and 26 days of age . Follicular germinal center was increased in number and size of the lymph nodes associated with the forestomach, suggesting activation of lymph apparatus . In the associated lymph nodes, IgG-containing cells were predominant and were located in both cortex and medulla, mainly in the medullary cord, B lymphocyte areas . Only a few IgA- and IgM-containing cells were observed in the lymph nodes . Accordingly, the inoculated bacteria may stimulate IgG-containing B lymphocyte populations . A few IgG-containing cells were detected in the mucosa of the forestomach . Ig-containing cells, predominantly IgG, were observed in the mucosa of the abomasum and intestine, and in the mesenteric lymph nodes . However, number of the cells in the mesenteric lymph nodes was smaller than that of the forestomach associated lymph nodes . The results suggest that the intraorally inoculated bacteria may stimulate the maturation of IgG positive lymphocytes in the lymph nodes associated with the forestomach.

J Clin Periodontol, 1990 Aug, 17(7 Pt 1), 414 - 8
The survival of subgingival plaque bacteria in an amine fluoride-containing gel; Bansal GS et al.; Subgingival plaque samples from 20 patients with chronic inflammatory periodontal disease were exposed to a commercial gel formulation containing 2 amine fluorides . The MIC of the gel for these samples ranged from 33 to 260 micrograms/ml with a modal value of 260 micrograms/ml . In each sample, the most resistant organisms (i.e., those organisms surviving at one doubling dilution below the MIC) were identified . 33 such organisms were isolated, of which 22 (67%) were strict anaerobes, and 25 (75%) were Gram negative . The 2 most frequent isolates were Bacteroides ruminicola ss . brevis and a Selenomonas species, neither of which is a recognised periodontopathogen . The gel had a rapid effect on the viability of the bacteria in the plaque samples, the 90% kill time being 17 min or less for 90% of the samples (range less than 5 to 71 min).

J Dent Res, 1990 Aug, 69(8), 1488 - 93
Genetic heterogeneity of Porphyromonas (Bacteroides) gingivalis by genomic DNA fingerprinting; Loos BG et al.; This study describes the use of total genomic DNA fingerprinting with the use of restriction endonucleases to characterize clinical isolates of Porphyromonas gingivalis (Bacteroides gingivalis) obtained from patients with periodontitis or with root-canal infections . The majority of independent isolates had a unique DNA fingerprint, indicating extensive genetic heterogeneity within this species . Twenty-nine distinct DNA fingerprints were found among the 33 isolates investigated . This is in contrast to biotyping and serotyping, where only one type and three types, respectively, have been reported . The observed heterogeneity indicates that DNA fingerprinting is a sensitive measure of genetic dissimilarity between P . gingivalis isolates and is able to characterize individual isolates . These results have ecological implications, indicating that there is considerable natural diversity in the global population of P . gingivalis, and that there are likely to be relatively large numbers of genetically distinct clonal lines . Furthermore, DNA fingerprinting is a sensitive and powerful tool for longitudinal and cross-sectional epidemiological studies . This technique provides far greater discrimination between isolates than either biotyping or serotyping, and will be most helpful in, for example, the analysis of distribution of clonal lines within one periodontal patient, or the analysis of the transmission to and turnover of strain populations within a patient population, since the probability of two strains with the same DNA fingerprint being found by chance is small.

Infect Immun, 1990 Aug, 58(8), 2542 - 6
Monoclonal antibody against a serotype antigen of Porphyromonas (Bacteroides) endodontalis and characteristics of the antigen; Hanazawa S et al.; Recent studies have demonstrated the presence of three serotypes (O1K1, O1K2, and O1K-) of Porphyromonas (Bacteroides) endodontalis . In the present study, a hybridoma cell line producing monoclonal antibody (BEE11) specific for serotype O1K1 of P . endodontalis was established . The specificity of the antibody was evaluated by enzyme-linked immunosorbent assay and immunoslot blot analysis . BEE11 antibody reacted with strains ATCC 35406, HG 400, and HG 421 of the bacterium . However, it did not react with HG 422 or HG 948 . Also, the antibody did not react with any of the black-pigmented Bacteroides strains tested . Although the antibody reacted with total cell envelope and capsule materials, it did not do so with lipopolysaccharide . The antibody reacted with antigen material having a molecular mass of 110 kilodaltons (kDa), as judged from fractionation by Superose 12 prep gel chromatography . When the peak fraction from the Superose 12 column was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) analysis, the reactivity was detected as a single band at an apparent molecular mass of about 52 kDa . The antigen material purified partially by high-performance liquid chromatography was sensitive to trypsin, V8 protease, and heating to 80 degrees C but not to neuraminidase . Therefore, the present study shows that BEE11 antibody recognizes a serotype antigen of P . endodontalis which may be a dimer consisting of monomers having molecular masses of approximately 52 kDa and sensitivity to proteases and heat.

Minerva Stomatol, 1990 Aug, 39(8), 637 - 40
{A comparative evaluation of oral and parenteral cephalosporins in inhibiting the growth of bacteria pathogenic to the periodontium}; Fanali S et al.; A study was carried out in vitro to assess the inhibitory activity on the growth of Bacteroides gingivalis and Bacteroides intermedius using two oral cephalosporins (Cephalexin and Cephradine) in comparison to two parenteral cephalosporins (Cefotaxime and Ceftriaxon) and the classic Tetracycline HCl . The results of the study show that the inhibitory activity on the growth of the two periodontopathogenic bacteria produced by the oral cephalosporins is comparable to that of other antibiotics studied, and that in comparison to parenteral cephalosporins the former have the advantage of being better accepted and more economic.

Acta Chir Scand, 1990 Aug, 156(8), 529 - 36
Host defence and bacterial growth in fosfomycin-treated peritonitis . Experimental observations in pigs; Berglund JE et al.; An approximately steady state of bacterial density intraperitoneally has been observed in bacterial peritonitis . This state, which follows an initial (0-4 h) phase of rapid elimination of bacteria, was now studied in a model of porcine peritonitis . Twelve pigs were intra-abdominally infected with 10(10) CFU each of Escherichia coli and Bacteroides fragilis . Six of the pigs received no antibiotic and six were given two doses of fosfomycin (anti-aerobic), 1 g i.v., with the aim of disturbing possible equilibrium between rapid proliferation and destruction of the sensitive E . coli . Levels of fosfomycin up to 90 times the minimum inhibitory concentration (1 mg/l) were detected in the peritoneal exudate, but the antibiotic had no discernible effect on E . coli density or elimination pattern compared with B . fragilis in the same pig or with observations in controls . The results favoured the concept of slow-replicating E . coli and hence declining activity of the defence mechanisms a few hours after the induction of peritonitis.

FEMS Microbiol Lett, 1990 Aug, 58(3), 317 - 20
Stability of soluble and extracellular vesicle-associated trypsin-like protease (TLP) activity of Bacteroides gingivalis W50; Smalley JW et al.; Comparison was made of the specific activities of whole extracellular soluble protein (EP) and extracellular vesicle (ECV)-associated trypsin-like protease (TLP) activity from batch cultures of Bacteroides gingivalis W50 . Rapid loss of activity occurred when these fractions were maintained at 37 degrees C in the presence of DTT . Residual levels of activity were detected after incubation of ECV and EP for up to 8 days under non-reducing conditions . Rates of activity loss in EP and ECV were similar . Mixtures of EP and ECV, in the same proportions as found in the culture supernatant showed neither depression nor elevation of total activity from the expected compound activities of the two separate fractions.

Antimicrob Agents Chemother, 1990 Aug, 34(8), 1546 - 50
Beta-lactamase production and susceptibilities to amoxicillin, amoxicillin-clavulanate, ticarcillin, ticarcillin-clavulanate, cefoxitin, imipenem, and metronidazole of 320 non-Bacteroides fragilis Bacteroides isolates and 129 fusobacteria from 28 U.S . centers; Appelbaum PC et al.; beta-Lactamase production (nitrocefin disk method) and agar dilution susceptibility of amoxicillin, amoxicillin-clavulanate, ticarcillin, ticarcillin-clavulanate, cefoxitin, imipenem, and metronidazole were determined for 320 Bacteroides species (not Bacteroides fragilis group) and 129 fusobacteria from 28 U.S . centers . Overall, 64.7% of Bacteroides species and 41.1% of fusobacteria were beta-lactamase positive . Among the Bacteroides species, positivity rates were highest for B . bivius (85.0%), followed by B . splanchnicus (83.3%), B . eggerthii (77.8%), and B . oralis (77.1%); 54.5% of black-pigmented Bacteroides species were beta-lactamase positive . Among the fusobacteria, Fusobacterium mortiferum showed the highest rate of beta-lactamase positivity (76.9%) . MICs of amoxicillin (128 micrograms/ml) and ticarcillin (64 micrograms/ml) for 90% of all beta-lactamase-positive strains were reduced to 4 and 2 micrograms/ml, respectively, with the addition of clavulanate . MICs of amoxicillin and ticarcillin for 90% of all beta-lactamase-negative strains were 1 and 4 micrograms/ml, respectively, and greater than or equal to 98.4% of the strains were susceptible to the beta-lactams tested . Of the beta-lactamase-producing strains, 45.9% were susceptible to amoxicillin at less than or equal to 4 micrograms/ml and 93.4% were susceptible to ticarcillin at less than or equal to 64 micrograms/ml; the addition of clavulanate raised the rates to 90.4 and 100%, respectively . All strains were susceptible to cefoxitin, imipenem, and metronidazole . The activity of amoxicillin against 29 beta-lactamase-producing strains (10 Bacteroides species and 19 fusobacteria) was not enhanced by the addition of clavulanate; however, 82.7% of these strains were susceptible to amoxicillin, and all were susceptible to ticarcillin . Although beta-lactamase positivity is on the increase in non-B . fragilis group Bacteroides species and fusobacteria, amoxicillin-clavulanate, ticarcillin, cefoxitin, imipenem, and metronidazole should be suitable for the treatment of infections with these strains . The addition of clavulanate does not appreciably improve the efficacy of ticarcillin against these organisms.

Nippon Juigaku Zasshi, 1990 Aug, 52(4), 711 - 7
Localization of bacterial antigens in calves inoculated orally with ruminal Bacteroides succinogenes and Selenomonas ruminantium; Sato S et al.; Localization of bacteria and bacterial materials was investigated in calves inoculated orally with live organisms of both Bacteroides succinogenes and Selenomonas ruminantium by a immunohistological method using rabbit antiserum against the outer membrane of those organisms and by a scanning electron microscope . The intact organisms of both inoculated bacterial species were detected on the rumen wall and in the lamina propria of the forestomach, and S . ruminantium also in the lymph nodes associated with the rumen . The bacterial materials were observed inside of macrophage-like cells in the lamina propria of the forestomach and of lymphoid cells in the lymph nodes . Number of the cells in the mesenteric lymph nodes was smaller than that of the forestomach associated lymph nodes . The results suggest that the orally inoculated bacteria may act as antigenical stimulant in the mucosa of the forestomach and associated lymph nodes of calves.

J Clin Periodontol, 1990 Aug, 17(7 Pt 1), 426 - 34
Clinical, microbiological and immunological studies on recurrent periodontal disease; Choi JI et al.; The present study was performed to evaluate the clinical, microbiological and immunological aspects in the early stages of recurrent periodontal disease . After clinical monitoring of pockets with recent evidence of disease recurrence, microbiological samples for cultural analysis, serum and gingival crevicular fluid (GCF) samples were taken for IgG antibody analysis from 14 sites, 7 in 6 recurrent periodontitis patients and 7 in 7 periodontally healthy control subjects . IgG responses of serum antibody to 8 gram-negative bacterial strains were compared with those of GCF sampled from the recurrent site . The results clearly demonstrated the predominance of Bacteroides gingivalis in most subgingival plaque samples during the early stages of disease recurrence; the mean proportions of B . gingivalis were significantly different from those of the healthy sites (p less than 0.05) . 4 out of 6 serum samples showed the elevated antibody responses to B . gingivalis 381; and this was closely correlated to homologous infection by this micro-organism in recurrent sites . Elevated serum antibody responses were also noted to Eikenella corrodens 1073 and Actinobacillus actinomycetemcomitans Y4 . However, no relationship with homologous infection was found for A . actinomycetemcomitans . 3 out of 6 GCF samples had greater antibody titers than the serum, suggesting local antibody synthesis by the gingival cells in the recurrent pockets . The present study showed that B . gingivalis might play an important role in the pathogenesis of disease recurrence in its early stages.

J Clin Periodontol, 1990 Aug, 17(7 Pt 1), 409 - 13
Bacteroides gingivalis stimulates bone resorption via interleukin-1 production by mononuclear cells . The relative role for B . gingivalis endotoxin; Bom-van Noorloos AA et al.; Supernatants of human peripheral blood mononuclear cells cultured in the presence of B . gingivalis, showed a strong osteoclast stimulating activity as measured by 45Ca release from fetal mouse long bones in vitro . These supernatants also contained a high concentration of bioactive and immunoreactive interleukin-1 (IL-1), but tumor necrosis factor (TNFa), another osteoclast-activating cytokine, was not detected . Osteoclast activation by the supernatants was inhibited by an antibody against IL-1, whereas ultrapure human IL-1 mimicked the effect of the supernatant . The ability of B . gingivalis to induce IL-1 and OAF production was heat sensitive, as 20 min heating of the bacteria at 120 degrees C caused a 50% loss of activity . In addition, purified B . gingivalis lipopolysaccharide (LPS) had little IL-1 inducing capacity, compared with LPS of Escherichia coli . These data suggest that human peripheral blood cells confronted with B . gingivalis produce large amounts of IL-1 which has strong osteoclast stimulating activity . However, in contrast with E . coli LPS, B . gingivalis LPS does not seem to be the major inducing agent . Thus other bacterial components must be responsible for the observed IL-1 and OAF induction.

J Bacteriol, 1990 Aug, 172(8), 4271 - 9
The region of a Bacteroides conjugal chromosomal tetracycline resistance element which is responsible for production of plasmidlike forms from unlinked chromosomal DNA might also be involved in transfer of the element; Stevens AM et al.; Large (greater than 50 kilobases) conjugal chromosomal tetracycline resistance (Tcr) elements have been found in many human colonic Bacteroides strains . Recently, N . B . Shoemaker and A . A . Salyers (J . Bacteriol, 170:1651-1657, 1988) reported that some of these Tcr elements appeared to mediate production of plasmidlike forms, NBU1 and NBU2, from an unlinked region of the chromosome of Bacteroides uniformis 0061 . Production of the plasmidlike forms and the transfer frequency of the Tcr elements were both enhanced by preexposure to tetracycline . Thus it appeared that genes involved in production of plasmidlike forms (Plf activity) might be coregulated with transfer genes and that Plf activity might have a role in transfer of the Tcr elements . By screening subclones of a Tcr element, Tcr Emr DOT, we have shown that the genes necessary for Plf activity on the Tcr element are within a 10-kilobase region adjacent to the Tcr gene . Subclones of this region were then used to construct insertional gene disruptions in a Tcr element, Tcr ERL, which is closely related to the Tcr Emr DOT element . Two of the disruption mutants were Plf- . Both had reduced transfer frequencies, one (omega RDB2) 10(2)-fold lower than that of the wild-type element and the other (omega RDBT) 10(4)-fold lower . omega RDB2 was also deficient in the ability to mobilize coresident plasmids, whereas omega RDBT exhibited nearly wild-type mobilization activity . The phenotypes of the mutants indicate that there are at least two genes necessary for Plf activity and that both may be involved in transfer of the element . The third disruption mutant (omegaRDB1), which expressed Plf constitutively, also had a transfer frequency 10(2) -fold lower than that of the wild-type element and was deficient in mobilization of coresident plasmids . The relationship between Plf genes and transfer, therefore, appears to be a complex one.

Antimicrob Agents Chemother, 1990 Aug, 34(8), 1597 - 9
In vitro susceptibilities of oral pigmented Bacteroides species to trospectomycin and other selected antimicrobial agents; Johnson CC et al.; The in vitro activity of trospectomycin against 97 clinical isolates of oral pigmented Bacteroides species was compared with the activities of five other antimicrobial agents . At 4 micrograms/ml, more than 90% of isolates were inhibited by trospectomycin . Overall, strains that produced beta-lactamase (n = 41) were more resistant to trospectomycin, penicillin G, cefoxitin, piperacillin, and tetracycline but not to clindamycin . In this study, trospectomycin had excellent in vitro activity against oral pigmented Bacteroides species.

J Clin Microbiol, 1990 Aug, 28(8), 1747 - 50
Selective medium for isolation of Bacteroides gracilis; Lee K et al.; A new medium selective for Bacteroides gracilis was developed . The medium is tryptic soy agar (Difco Laboratories, Detroit, Mich.) containing nalidixic acid, teicoplanin, sodium formate, sodium fumarate, and potassium nitrate . All 18 strains of B . gracilis tested grew with only minimal inhibition . Most of the other 214 organisms tested, including most Bacteroides species, other anaerobes, and a substantial number of facultative anaerobes, were significantly inhibited by the medium . In a diagnostic study of 49 clinical specimens (28 patients with intra-abdominal infection, mostly gangrenous or perforated appendicitis), four strains of B . gracilis were isolated (from 4 different patients) on B . gracilis selective agar but were not detected on standard media.

Endod Dent Traumatol, 1990 Aug, 6(4), 153 - 6
Demonstration of Bacteroides intermedius in periapical tissue using indirect immunofluorescence microscopy; Barnett F et al.; The presence of bacteria in periapical lesions of teeth with necrotic pulp has been demonstrated by microbiological sampling of periapical lesions during endodontic surgery . The purpose of this study was to confirm the presence of Bacteroides intermedius in a periapical granuloma using an indirect immunofluorescence technique . Histologic sections of a periapical granuloma were incubated with a rabbit antiserum to B . intermedius . After incubation with secondary antibody (fluorescein-conjugated goat anti-rabbit IgG), an intense fluorescent staining was observed in areas of the tissue sections . Control tissue sections that were incubated without the antibody remained unstained . The results obtained with the indirect immunofluorescence technique supported our cultural findings that microorganisms, e.g . B . intermedius, were present in the tissue of the periapical granuloma.

Oral Microbiol Immunol, 1990 Aug, 5(4), 208 - 12
Characterization and physical mapping of plasmids of black-pigmented Bacteroides; Yoshimoto H et al.; Eight species of black-pigmented Bacteroides (BPB) were examined for plasmid content . Three classes of plasmids with molecular sizes of 16.0 kilobase (kb), 5.4 kb and 5.0 kb were found in 7 of 125 Bacteroides intermedius strains . One strain each of Porphyromonas (former Bacteroides) asaccharolyticus and of Bacteroides levii were also shown to have plasmids . However, no plasmids were detected in 90 strains of Porphyromonas (Bacteroides) gingivalis . The plasmids were purified and digested with restriction endonucleases for restriction mapping . The maps obtained in this study have given us information on the scheme of constructing recombinants which may be usable as shuttle vectors, by the recombination of BPB and Escherichia coli plasmids.

Oral Microbiol Immunol, 1990 Aug, 5(4), 202 - 7
Ingestion of Bacteroides buccae, Bacteroides oris, Porphyromonas gingivalis, and Fusobacterium nucleatum by human polymorphonuclear leukocytes in vitro; Kerosuo E et al.; The phagocytic ingestion of clinical isolates and reference strains of Bacteroides buccae, Bacteroides oris, Porphyromonas gingivalis and Fusobacterium nucleatum by polymorphonuclear leukocytes (PMNs) was studied . Special attention was focused on the hydrophobicity of the strains . B . buccae strains, less or equally hydrophobic than PMNs, were poorly ingested without opsonization . Hydrophobic, but not hydrophilic, strains of B . oris and both hydrophilic and hydrophobic P . gingivalis and F . nucleatum strains were readily ingested without opsonization . Hydrophobicity thus contributes to the adherence of bacteria to PMNs in some, but not all, species tested . Normal human serum enhanced the ingestion of B . buccae, but failed to do so after heat-inactivation . Heat-inactivation of the immune serum to B . buccae strain ES57 did not reduce opsonic activity suggesting that specific antibodies enhanced the ingestion of B . buccae.

J Clin Periodontol, 1990 Aug, 17(7 Pt 1), 419 - 25
The relationship of serum IgG antibody titers to periodontal pathogens to indicators of the host response in crevicular fluid; Lamster IB et al.; In this study; the relationship of indicators of the local host response in gingival crevicular fluid (GCF) to the serum antibody titer to periodontal pathogens was examined . 15 patients with chronic adult periodontitis were studied . GCF was collected and analyzed for the total amount of IgG, IgM, the lysosomal enzyme B-glucuronidase (BG) and alpha-2-macroglobulin (alpha 2M) . At the same examination, serum from these patients was collected, and enzyme-linked immunosorbent assays used to determine the serum IgG antibody titer to a panel of 17 periodontal pathogens (Actinobacillus actinomycetemcomitans (3 strains), Bacteroides gingivalis (4), Eikenella corrodens (2), Wolinella recta, Bacteroides intermedius (3), Fusobacterium nucleatum, and 3 Capnocytophaga species) . Using Spearman rank order correlation analysis, correlation coefficients were calculated to relate the 4 indicators of host response in GCF to the serum IgG antibody titer to each of the 17 micro-organisms . The mean correlation between total IgG in GCF and the serum IgG antibody titer was positive (r = +0.30), and statistically significant correlations between total IgG in GCF and serum IgG antibody titer were observed for one strain of B . intermedius and C . ochracea . A weaker positive correlation was observed for IgM (r = 0.18) . In contrast, the mean correlation between total BG in GCF and the serum antibody titer was negative (r = -0.34) . Statistically significant negative correlations were observed for all 3 strains of A . actinomycetemcomitans, one strain of E . corrodens and W . recta . The mean correlation for alpha 2M was r = -0.06 . These data suggest that elevated BG activity in GCF, believed to be a marker for lysosomal enzyme released from polymorphonuclear leukocytes in the crevicular environment, may be associated with a reduced serum IgG antibody response to suspected periodontal pathogens . Furthermore, these findings imply that the development of a serum IgG antibody response to suspected periodontal pathogens is consistent with a protective host response.

Med Lab Sci, 1990 Jul, 47(3), 163 - 7
Increase in the activity of third-generation cephalosporins in combination with clavulanic acid and Sulbactam against Bacteroides fragilis; Martin MA et al.; We studied the sensitivity of 160 strains of Bacteroides fragilis (74 beta-lactamase-positive and 86 beta-lactamase-negative) to four third-generation cephalosporins, alone as well as in combination with clavulanic acid and Sulbactam . For susceptibility testing we used a dilution method in agar . Detection of beta-lactamase production by this micro-organism was performed using chromogenic cephalosporin (Nitrocefin) . There was a substantial improvement in cephalosporin activity with both positive and negative strains when they were combined with the inhibitors, although this was more significant in beta-lactamase-producing organisms . Generally, the results achieved in combination with clavulanic acid were better than those with Sulbactam, the highest increase in activity being obtained with Ceftizoxime in combination with any one of the inhibitors.

J Clin Periodontol, 1990 Jul, 17(6), 392 - 9
Occurrence of Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans in severe periodontitis in relation to age and treatment history; Rodenburg JP et al.; A total of 242 subjects including 138 untreated severe periodontitis patients and 104 patients with refractory periodontal disease, previously treated for severe periodontitis, were examined for the occurrence of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Bacteroides intermedius . Pooled subgingival samples of representative periodontal lesions were used for anaerobic cultivation on blood agar and for the enumeration of A . actinomycetemcomitans on selective TSBV medium . 97% of the untreated patients were infected with one or more of the test micro-organisms . In this patient group, the occurrence of A . actinomycetemcomitans, B . gingivalis and B . intermedius was 54%, 48% and 63%, respectively . The prevalence of A . actinomycetemcomitans positive patients appeared to be age related and decreased with increasing age . Likewise, the number of patients solely infected with A . actinomycetemcomitans decreased with increasing age . The prevalence of B . gingivalis infected patients appeared to increase with increasing age . These phenomena were not observed in the refractory periodontitis patients . The occurrence of A . actinomycetemcomitans, B . gingivalis and B . intermedius in the refractory periodontitis group was 55%, 27% and 59%, respectively . A statistical significant difference in the prevalence of B . gingivalis was found between the untreated and the refractory periodontitis patients . In both patient groups, the relative proportion of A . actinomycetemcomitans was significantly higher in subjects with this bacterium as the sole indicator micro-organism than in patients who, besides being infected with A . actinomycetemcomitans, were also infected with black-pigmented Bacteroides species . Furthermore, in comparison with untreated patients, unsuccessfully treated patients solely infected with A . actinomycetemcomitans had on average a lower number but also a higher mean % of this bacterium.(ABSTRACT TRUNCATED AT 250 WORDS)

J Appl Bacteriol, 1990 Jul, 69(1), 125 - 33
High-performance liquid chromatographic analysis of alpha-keto acids produced from amino acid metabolism in oral Bacteroides; Tsuchiya H et al.; Profiles of metabolic alpha-keto acids were determined by a high-performance liquid chromatographic method and applied to characterization of oral black-pigmented Bacteroides . Each bacterial strain was incubated with amino acids in a chemically defined medium . After production alpha-keto acids were purified by hydrazide gel column treatment and converted to u.v.-absorbing derivatives . They were analysed by reversed-phase ion-pair chromatography . Black-pigmented Bacteroides species were differentiated into two groups according to production of aromatic alpha-keto acids . Bacteroides gingivalis, B . endodontalis and B . loescheii produced both p-hydroxyphenylpyruvic and phenylpyruvic acids . However, no such alpha-keto acids were produced by B . levii, B . intermedius and B . denticola . In addition, production profiles of several aliphatic alpha-keto acids (alpha-ketoglutaric, pyruvic, alpha-ketobutyric, alpha-ketoisovaleric, alpha-ketoisocaproic, and alpha-keto-beta-methylvaleric acids) separated each individual species in such groups . The present study offers useful chemotaxonomic information on amino acid metabolic activity of oral black-pigmented Bacteroides species.

Appl Environ Microbiol, 1990 Jul, 56(7), 2243 - 4
Enumeration of enterotoxigenic Bacteroides fragilis in municipal sewage; Shoop DS et al.; Of 237 isolates of Bacteroides fragilis from sewage influent at the Bozeman, Mont., wastewater treatment plant, 22 (9.3%) were enterotoxigenic, as indicated by the ability to elicit fluid accumulation in the lamb ileal loop test . It appears that enterotoxigenic B . fragilis is endemic in the human population at a moderately high level.

J Periodontol, 1990 Jul, 61(7), 427 - 33
Irrigation with 0.06% chlorhexidine in naturally occurring gingivitis . II . 6 months microbiological observations; Newman MG et al.; In an examiner blind positive/negative controlled 6-month study, the efficacy of supragingival irrigation with 0.06% chlorhexidine gluconate on the marginal and subgingival microflora in naturally occurring gingivitis was evaluated . The 222 patients enrolled in the study were assigned to one of four groups: Group 1: Once daily irrigation with 300 ml water followed by irrigation with 200 ml 0.06% chlorhexidine gluconate (experimental); Group 2: Twice daily rinsing with 15 ml 0.12% chlorhexidine (positive control); Group 3: Once daily irrigation with 500 ml water (irrigation control) and Group 4: Sodium fluoride dentifrice for normal oral hygiene only (negative control) . All groups received the same sodium fluoride dentifrice for tooth brushing . All patients received a supra- and subgingival oral prophylaxis after baseline examination and at the end of the investigation . Plaque samples were analyzed from 105 patients at baseline, 93 patients at 3 months and 88 patients at 6 months . The 6-months results demonstrated that, when compared with tooth brushing alone, adjunctive supragingival irrigation with 0.06% chlorhexidine gluconate was most effective by significantly reducing (P less than or equal to 0.008) both log10 CFU and % of Gram-negative anaerobic rods and black-pigmented Bacteroides . Chlorhexidine rinse also significantly (P less than or equal to 0.008) reduced log10 CFU of black-pigmented Bacteroides at 6 months . Both chlorhexidine regimens significantly (P less than or equal to 0.008) increased the % of Gram-positive facultative cocci compared to water irrigation at 3 months . Water irrigation had a limited effect on any of the assessed bacterial groups (log10 CFU and %).(ABSTRACT TRUNCATED AT 250 WORDS)

J Clin Microbiol, 1990 Jul, 28(7), 1658 - 60
Rabbit model to evaluate enterovirulence of Bacteroides fragilis; Myers LL et al.; Enterotoxigenic Bacteroides fragilis elicited fluid accumulation in the intestinal tract and exfoliation of epithelial cells in the proximal colon of the 2-week-old rabbit . The rabbit model was employed to screen isolates of B . fragilis for enterovirulence and to study the pathogenesis of disease caused by enterotoxigenic B . fragilis.

J Clin Microbiol, 1990 Jul, 28(7), 1551 - 9
Development of a diagnostic test for anaerobic periodontal infections based on plaque hydrolysis of benzoyl-DL-arginine-naphthylamide; Loesche WJ et al.; Treponema denticola, Porphyromonas (Bacteroides) gingivalis, and Bacteroides forsythus are among the anaerobic species frequently associated with adult forms of periodontal disease . These organisms hydrolyze the synthetic peptide benzoyl-DL-arginine-naphthylamide (BANA), and such enzyme activity can be detected in the plaque and related to clinical disease and the presence of spirochetes . In this investigation, the liquid BANA assay was compared with a commercially developed BANA assay which employed a paper format and which could be read after a 15-min incubation . In the paper format, strips of a Whatman filter paper were impregnated with BANA and strips of nitrocellulose paper were impregnated with fast black K salt . Both strips were applied lengthwise across a paper card (3 by 5 in . {7.6 by 12.7 cm}) . The BANA strip at the bottom was inoculated with the test sample (pure culture, plaque), folded back so that it contacted the fast black strip, and then incubated for 15 min at 55 degrees C . T . denticola, P . gingivalis, and B . forsythus always gave a positive reaction, whereas 51 other plaque species were always negative . Six Bacteroides and Capnocytophaga species on occasion had weak reactions . The proportional agreement between BANA positiveness and clinical disease was similar for both the liquid and the paper assays . The sensitivity, specificity, and accuracy relative to the clinical standard of the liquid assay were 74, 76, and 77%, respectively, while those of the paper assay were 81, 78, and 80%, respectively . The paper assay was significantly associated with the presence of either T . denticola or P . gingivalis or both in the plaque samples, with a sensitivity of 85%, a specificity of 53%, and an accuracy of 79% . These findings indicate that a rapid paper assay for BANA hydrolysis gives data comparable to those obtained with the liquid BANA assay.

Can J Microbiol, 1990 Jul, 36(7), 490 - 4
Induction and repair of DNA strand breaks in Bacteroides fragilis; Abratt VR et al.; Alkaline sucrose gradient sedimentation was used to establish whether strand breakage and repair take place in the DNA of UV-irradiated Bacteroides fragilis during the removal of pyrimidine dimers . A B . fragilis wild-type strain and two of its repair mutants, a mitomycin C sensitive mutant (MTC25) having wild-type levels of UV survival, and a UV-sensitive, mitomycin C sensitive mutant (UVS9), were investigated . Under anaerobic conditions, far-UV irradiation induced metabolically regulated strand breakage and resynthesis in the wild-type strain, but this was markedly reduced in both the MTC25 and UVS9 mutants . Approximately half of the strand breaks generated by the various strains were rejoined during further holding in buffer . Under replicating conditions, complete repair of strand breaks in the wild type was observed . Caffeine treatment under anaerobic conditions caused direct DNA strand breakage in B . fragilis cells but did not inhibit UV-induced breakage or repair.

J Antimicrob Chemother, 1990 Jul, 26(1), 7 - 20
Alterations to the penicillin-binding proteins in the Bacteroides fragilis group: a mechanism for non-beta-lactamase mediated cefoxitin resistance; Wexler HM et al.; The penicillin-binding proteins (PBPs) of ATTC Type Strains of nine species of the Bacteroides fragilis group were visualized by gel electrophoresis and subsequent fluorography . Each species had a distinctive PBP pattern, although variation within species was seen . Generally, five PBPs could be visualized, ranging in molecular weight from approximately 40,000 to approximately 90,000 . A laboratory-derived cefoxitin-resistant mutant of B . distasonis was compared with its wild type parent and cefoxitin-sensitive revertant . The fluorograph of the resistant mutant indicated a marked reduction of labelling to the PBP-1 complex as compared with the wild type and revertant . Cefoxitin-resistant clinical isolates of B . thetaiotaomicron and B . uniformis also showed changes to the PBP-1 complex, in comparison with sensitive strains.

J Clin Periodontol, 1990 Jul, 17(6), 345 - 50
Effect of root debridement on the elimination of Actinobacillus actinomycetemcomitans and Bacteroides gingivalis from periodontal pockets; Renvert S et al.; The aims of this 6-month longitudinal study were: (1) to investigate to what extent root debridement of pockets in adult periodontitis will reduce the subgingival presence of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and some other bacterial groups; (2) to relate the microbiological results following debridement to clinical measurements of healing . 16 patients and a total of 111 periodontally involved sites with probing depth greater than or equal to 6 mm served for the study . Duplicate subgingival microbial samples and duplicate clinical recordings were obtained 1 week apart at baseline and at 6 months following supra- and subgingival debridement . The results demonstrated reductions of the mean total viable counts and reductions of the mean counts of several of the cultured groups of micro-organisms coupled with significant improvements of mean clinical measurements . B . gingivalis was eliminated from a majority of infected subgingival sites . A . actinomycetemcomitans, on the other hand, still remained after therapy in a high proportion of sites initially infected with this microorganism . Subgingival persistence of A . actinomycetemcomitans appeared to be associated with a reduced healing response following debridement . Further studies are needed to clarify why A . actinomycetemcomitans is poorly eliminated following debridement . Also, the long-term clinical significance of the subgingival perseverance of A . actinomycetemcomitans needs to be elucidated.

J Periodontal Res, 1990 Jul, 25(4), 207 - 14
The release of interleukin-1 beta, tumor necrosis factor-alpha and interferon-gamma by cultured peripheral blood mononuclear cells from patients with periodontitis; McFarlane CG et al.; The extracellular release of IL-1 beta by cultured peripheral blood monocytes from 26 periodontitis patients and 26 control subjects was measured by radioimmunoassay . Unstimulated monocytes from periodontitis patients released significantly more IL-1 beta than controls during 24 h of culture; there was a wide variation in the amount of IL-1 beta released (0.45-13.00 ng/ml per 10(6) cells) which did not correlate with either the degree of bone loss or pocket formation observed clinically . When stimulated with lipopolysaccharide (LPS; Actinobacillus actinomycetemcomitans; 5 micrograms/ml) monocytes from periodontitis patients produced significantly more IL-1 beta than those from control subjects . Monocyte culture supernatants from another 10 periodontitis patients and 10 control subjects were also assayed for both IL-1 beta and TNF-alpha by enzyme-linked immunosorbent assays . Spontaneous and LPS-stimulated (Bacteroides gingivalis; 5 micrograms/ml) IL-1 beta release were again significantly higher for periodontitis patients . TNF-alpha was detected in the periodontitis cultures (0-765 pg/ml per 10(6) cells), but the mean value was not significantly different from controls . LPS-stimulated TNF-alpha release, however, was significantly higher than for control subjects, and there was a strong correlation between spontaneous IL-1 beta and TNF-alpha release by monocytes from the periodontitis group . Measurement of interferon-gamma (IFN-gamma) in lymphocyte cultures from these patients by immunoradiometric assay showed that IFN-gamma levels in periodontitis cultures were consistently low, but not significantly so when compared to controls; both groups responded equally to concanavalin-A (5 micrograms/ml) . Although the precise roles of IL-1 beta and TNF-alpha in periodontitis remain unclear, these data provide evidence that both cytokines may participate in the pathogenesis of the disease.

Int J Prosthodont, 1990 Jul-Aug, 3(4), 369 - 74
Clinical and microbial evaluation of treatment regimens to reduce denture stomatitis; DePaola LG et al.; This study evaluated the effect of an antimicrobial mouthrinse, denture soft relines, and a placebo rinse on the clinical findings and microbial flora of 78 patients with denture stomatitis . For 28 days the study and control groups performed oral rinses and denture soaks . Reline group patients had maxillary denture soft relines that were changed every 7 days . At the end of the study, the mean severity of denture stomatitis was significantly less in the groups that used the study rinse (P less than 0.01) and received denture relines (P less than 0.05) compared to the control . Analysis of variance revealed significant differences in ranked adjusted percentage counts in two out of 13 denture plaque organisms investigated (Fusobacterium nucleatum {P less than 0.05} and total Bacteroides {P less than 0.05}), with the antiseptic rinse producing the lowest count . Yeast populations were reduced, but not significantly (P = 0.07) . In the absence of other mechanical denture hygiene procedures, the antiseptic rinse and relines were equally effective in reducing denture stomatitis and potential pathogens of denture plaque flora.

Bull Group Int Rech Sci Stomatol Odontol, 1990 Jul, 33(2), 83 - 8
{A comparison of culture and immunofluorescence technics in the study of Bacteroides with black pigmentation}; Robert JC et al.; The aim of that study was to compare culture and immunofluorescence (IF) methods to determine whether B . gingivalis and other B.P.B . can be detected in subgingival plaque of children . Samples were collected from the lingual sulcus of mandibular incisors, dispersed and diluted from 1 to 10(-5); 15 microliters of each dilution were plated on Trypticase soja agar and Todd-Hewitt agar supplemented with blood, Vit K 1 and hemin . The same dilutions were smeared on glass slides for indirect IF using an species-specific polyclonal rabbit whole cell antiserum to B . gingivalis ATCC 33 277 . Representative colonies producing brown-to-black pigment were isolated, purified and further characterized . Using culture, BPB were detected in 46% of children (19/41) . B . gingivalis was cultured from 6 children . Using immunofluorescence test (Fluotec*), 90% of 309 children 3 years old and more harbour detectable B.P.B., but B . gingivalis don't react with that test . B . gingivalis were detected by immunofluorescence in 72% of children (30/41) in the incisor plaque.

Diagn Microbiol Infect Dis, 1990 Jul-Aug, 13(4), 311 - 6
Differences in the in vitro inhibitory and bactericidal activity of ceftizoxime, cefoxitin, cefotetan, and penicillin G against Bacteroides fragilis group isolates . Comparison of time-kill kinetic studies with MIC values; Aldridge KE et al.; Nineteen strains of the Bacteroides fragilis group were used to determine the bactericidal activity of ceftizoxime, cefoxitin, cefotetan, and penicillin G with time-kill kinetics studies . Each antimicrobial agent was tested at subinhibitory (1/2 X MIC), inhibitory (1 X MIC), and suprainhibitory (4 X MIC) concentrations . Penicillin G exhibited virtually no sustained bactericidal activity at any of the antimicrobial concentrations tested . At subinhibitory concentrations, ceftizoxime was considerably more bactericidal than cefoxitin or cefotetan: At 12 hr, ceftizoxime killed 89% of the inoculum, whereas cefoxitin and cefotetan killed 35% and 33% of the inoculum, respectively . At inhibitory concentrations, ceftizoxime was again more bactericidal than cefoxitin and cefotetan: At 12 hr, ceftizoxime killed 90% of the inoculum, whereas cefoxitin and cefotetan killed 78% and 73%, respectively . At suprainhibitory concentrations, all three antimicrobial agents showed comparable bactericidal activity at 12 and 24 hr . Ceftizoxime and cefoxitin had somewhat lower killing rates overall against test strains with high MICs (greater than or equal to 32) versus low MICs (less than or equal to 16) . However, at subinhibitory concentrations, ceftizoxime killed the B . fragilis group strains with high or low MIC values more effectively than cefotetan killed strains with low MICs . At the highest antibiotic concentrations tested (4 X MIC), only slight differences were seen in the bactericidal activity of the three compounds, regardless of MICs.

Zhonghua Kou Qiang Yi Xue Za Zhi, 1990 Jul, 25(4), 197 - 9, 251
{Relationship between serum antibody to Bacteroides gingivalis and clinical parameters in periodontitis patients}; Cao CF et al.; Prevalence and proportion of black-pigmented Bacteroides species (BPB) in supragingival and subgingival plaque were determined in ten adult periodontitis patients . Serum antibody against Bacteroides gingivalis (Bg) of these patients were tested using ELISA . Clinical parameters (PI, GI, PD, AL) were collected prior to blood withdrawn . Results showed that BPB were detected in all patients . Mean serum anti-Bg IgG level was significantly greater in the patient group than that in healthy control group . Although the sample size was too small to show statistical difference, there was a trend showing the sera anti-Bg IgG level tended to be greater in accordance with the increase of disease severity and BPB%.

Gut, 1990 Jul, 31(7), 770 - 6
Effects of an enteric anaerobic bacterial culture supernatant and deoxycholate on intestinal calcium absorption and disaccharidase activity; Walshe K et al.; Fifty two strains of anaerobic bacteria isolated from the upper gut of patients with small intestinal bacterial overgrowth were screened for phospholipase activity . Bacteroides melaninogenicus spp intermedius had the greatest activity . The effects of culture supernatants of this organism and deoxycholate on intestinal calcium absorption and disaccharidase activity were studied using a rat closed loop model . The supernatant decreased the in vitro uptake of calcium by 15% (p less than 0.001) . Deoxycholate reduced calcium uptake by 16% (p less than 0.001) . Combined culture supernatant and deoxycholate reduced calcium uptake by 39% (p less than 0.001) suggesting a potentiation of supernatant activity by deoxycholate . Culture supernatant and deoxycholate, both alone and combined, significantly reduced lactase, sucrase, and maltase activity . Electron microscopic evidence showed degeneration of microvilli, disruption of mitochondrial structure, and swelling of the endoplasmic reticulum after exposure of the intestinal loops to the supernatant or deoxycholate.

Lett Appl Microbiol, 1990 Jul, 11(1), 18 - 21
Deoxyribonuclease activity in rumen bacteria; Flint HJ et al.; Deoxyribonuclease activity was surveyed in 22 strains belonging to 12 species of rumen bacteria, with lambda bacteriophage DNA as substrate . Activity was readily detected in broken cell preparations from 15 of these strains . Particularly high levels of activity were present in cells and culture supernatant of all 5 strains of Bacteroides succinogenes, and 2 out of 6 strains of Bacteroides ruminicola, examined.

Eur J Clin Microbiol Infect Dis, 1990 Jun, 9(6), 417 - 21
Susceptibility of Bacteroides non-fragilis and fusobacteria to amoxicillin, amoxicillin/clavulanate, ticarcillin, ticarcillin/clavulanate, cefoxitin, imipenem and metronidazole; Jacobs MR et al.; The susceptibility of 234 Bacteroides non-fragilis strains and 56 fusobacteria from 12 European centers to amoxicillin, amoxicillin/clavulanate, ticarcillin, ticarcillin/clavulanate, cefoxitin, imipenem and metronidazole was tested and related to beta-lactamase production . Beta-lactamase production was detected in 42.3 % of the Bacteroides strains and 26.8% of the fusobacteria . The MIC90 of amoxicillin for beta-lactamase-negative strains was 0.5 microgram/ml and the MIC90 of ticarcillin 2.0 micrograms/ml . In the case of beta-lactamase-positive strains the MIC90 of amoxicillin (32 micrograms/ml) and ticarcillin (16 micrograms/ml) dropped to less than or equal to 1.0 microgram/ml upon addition of clavulanate; 65.8% of these strains were susceptible to amoxicillin and 98.2% to ticarcillin, but all were susceptible when clavulanate was added . All strains were susceptible to imipenem and metronidazole, and 99.3% to cefoxitin.

J Antimicrob Chemother, 1990 Jun, 25(6), 1011 - 9
The antimicrobial susceptibility patterns of the Bacteroides fragilis group in the United States, 1987; Cornick NA et al.; A nationwide survey to monitor the susceptibility of the Bacteroides fragilis group, which began in 1981, was continued during 1987 . In addition to the eleven drugs evaluated in 1986, sulbactam, a potent beta-lactamase inhibitor, was tested alone and in combination with ampicillin and cefoperazone . Imipenem, ampicillin/sulbactam, cefoperazone/sulbactam, and ticarcillin/clavulanic acid were the most active newer drugs tested, with less than 1% resistance rates . Chloramphenicol, metronidazole and clindamycin also had excellent activity with resistance rates of 0%, 0%, and 3% respectively . Resistance rates to cefoxitin remained stable at 8% . Ceftizoxime and cefotetan had resistance rates of 26% and 29%, respectively . Rates of resistance varied among different institutions and between the various species.

Aust N Z J Surg, 1990 Jun, 60(6), 488 - 9
Retroperitoneal dermoid presenting as an infected pancreatic cyst; Dewar G et al.; Bacteroides fragilis infection of a juxtapancreatic benign cystic retroperitoneal teratoma in a 28 year old Chinese male is reported . Preliminary drainage was followed by excision . The radiological and pathological findings of this rare tumour are reported with emphasis on the differential diagnosis which includes inflammatory and neoplastic pancreatic cysts.

Can J Ophthalmol, 1990 Jun, 25(4), 208 - 9
Bacteroides fragilis endophthalmitis: a case report; Kelly LD et al.; Bacteroides fragilis is an infrequent anaerobic ocular pathogen . Nevertheless, this organism is of particular significance because it may be resistant to many antibiotics that are typically effective against anaerobes . We present what is to the best of our knowledge the first reported case of B . fragilis endophthalmitis . The endophthalmitis presented in a 95-year-old man following extracapsular cataract extraction with posterior chamber intraocular lens implantation.

Appl Environ Microbiol, 1990 Jun, 56(6), 1944 - 8
Expression and regulation of a Bacteroides fragilis sucrose utilization system cloned in Escherichia coli; Scholle RR et al.; A Bacteroides fragilis strain isolated from human feces was the source of chromosomal DNA in the construction of plasmid pBS100 . The cloned 6-kilobase insert of plasmid pBS100 conferred a sucrose positivity phenotype on transformed cells of Escherichia coli JA221 . E . coli JA221(pBS100) cells were able to utilize sucrose as the sole source of carbon because of the presence of sucrase enzyme and sucrose uptake activities . Sucrase activity was inducible in B . fragilis but constitutive in E . coli JA221(pBS100) cells . In sucrose-minimal medium, both B . fragilis and E . coli JA221(pBS100) produced intracellular and extracellular sucrase activities throughout the growth cycle . Osmotic shock experiments performed on E . coli JA221(pBS100) indicated that up to 55% of the sucrase activity was localized in the periplasmic space, 30% was in the cytoplasm, and the remaining 15% was in the cell-free extracellular supernatant fluid . B . fragilis and E . coli JA221(pBS100) actively transported sucrose . Sucrose uptake was induced by sucrose in B . fragilis, whereas the uptake activity in E . coli JA221(pBS100) was constitutive . E . coli JA221(pBS100) appeared to transport sucrose by a phosphotransferase-independent system . B . fragilis transported sucrose only under strictly anaerobic conditions . No uptake activity was detected under aerobic conditions with or without addition of catalase.

Nichidai Koko Kagaku, 1990 Jun, 16(2), 175 - 95
{Changes of factors on disease activity in advancing periodontitis}; Masunaga H; Two test teeth, anteriors with greater than or equal to 6 mm deep periodontal pockets from each of 10 patients with advancing periodontitis were included in this study . The clinical signs of advancing periodontitis, generalized moderate to deep pockets and to severe loss of alveolar bone, were observed in young adult . There have been several reports on factors, which reflect the conversion clinically from infection by highly pathogenic plaque bacteria to a from of periodontitis displaying relatively rapid loss of clinical attachment . The purpose of this investigation was to detect parameters in fluid, which could leak from the underlying inflamed connective tissue into the gingival crevice, and which could shown correlatively the progressive variations of periodontal disease by recurrent acute stage . In order to determine active disease sites and to monitor guantitatively response to therapy or to measure degree to susceptibility of future breakdown . Examinations on following parameters at pre- and post- periodontal treatment stages were carried out . Endotoxin, collagenase, alkaline phosphatase, beta-glucuronidase, interleukin-1 alpha, IgG antibody levels to Bacteroides gingivalis, Bacteroides intermedius were measured in gingival exudate samples, which were collected by the microtips technique from periodontal pockets . The following results were obtained: 1) Considering the effect of periodontal therapy, pathogenic responses on total colony forming unit (CFU), interleukin-1 alpha and changes of endotoxin and beta-glucuronidase levels after the treatment have indicated that specific changes in humoral responses . 2) There was not significant relation between alkaline phosphatase, collagenase, IgG antibodies level to Bacteroides gingivalis, Bacteroides intermedius and responses in active and also inactive disease sites . 3) This study has been resulted in the development of diagnostic techniques which requires strict criteria on the disease activity of the periodontal disease very specific in order to permit a more scientific approach to the care of periodontitis patients and to speculate the prognosis of the patients after the treatment.

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