Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031099 (periodontitis)
 12,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eleven strains of Eikenella corrodens with beta-lactamase activity were isolated from a patient with refractory periodontitis who had previously been treated with penicillin antibiotics. These strains were relatively resistant to benzylpenicillin, amoxicillin, and ampicillin (MICs, greater than or equal to 64 micrograms/ml); susceptible to amoxicillin-clavulanate (2:1) (MICs, less than or equal to 4 micrograms/ml); and moderately susceptible to cephalothin and cephaloridine (MICs, 0.12 to 16 micrograms/ml). The addition of 1 microgram of potassium clavulanate, a beta-lactamase inhibitor, per ml resulted in a significant increase in the susceptibilities of these strains to penicillins but not to cephalosporins. Potassium clavulanate had no effect on non-beta-lactamase-producing strains. Enzyme production was constitutive since activity was not increased when cells were cultivated in the presence of benzylpenicillin. Enzyme activity was strongly inhibited by potassium clavulanate, sulbactam, and iodine; weakly inhibited by cloxacillin, imipenem, and moxalactam; but not inhibited by aztreonam, EDTA, or p-chloromercuribenzoate. By gel infiltration, the enzyme had an estimated molecular mass of 29 kDa. Isoelectric focusing of the partially purified enzyme gave a major beta-lactamase band at pH 5.50 and a minor band at pH 5.60. Plasmids were not detected in any of the 11 beta-lactamase-positive strains. This enzyme is considered to belong to class 2a of the Bush classification scheme.
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PMID:Characterization of a beta-lactamase found in Eikenella corrodens. 185 71

Subgingival plaque samples from 20 patients with chronic periodontitis who had received no antibiotics for at least 3 months were screened for the presence of beta-lactamase-producing bacteria. Thirteen of the patients harboured beta-lactamase producing bacteria, most of which were members of the genus Bacteroides. The most frequently isolated species were Bacteroides melaninogenicus and Bacteroides capillosus which are often implicated in acute oral infections. All of the beta-lactamase-producing bacteroides strains were sensitive to a combination of amoxycillin with clavulanic acid (Augmentin).
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PMID:The prevalence of beta-lactamase producing bacteria in subgingival plaque and their sensitivity to Augmentin. 198 62

The currently accepted empiric antibiotic therapy for bacterial infections in neutropenic patients may not cover the possibility of capnophilic and anaerobic bacteremia. Many of these infections develop in patients with severe mucositis or periodontitis, and the type of organisms recovered also suggests an oral source of infection. We present two cases of bacteremia in neutropenic patients who had been empirically treated with ceftazidime and piperacillin plus amikacin. In the first case a beta-lactamase-producing strain of Capnocytophaga ochracea was isolated; in the second case bacteremia was due to a mixture of Leptotrichia buccalis and Fusobacterium nucleatum. These observations emphasize the necessity for a reevaluation of the possible use of antimicrobial agents active against beta-lactamase-producing capnophilic organisms and anaerobic bacteria during empiric therapy in neutropenic patients with an oral source of infection.
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PMID:Capnophilic and anaerobic bacteremia in neutropenic patients: an oral source. 230 82

In this investigation, the penicillin-resistant and beta-lactamase-producing subgingival microbiota associated with adult periodontitis was identified, and the impact of a recent exposure to penicillin on the recovery of resistant organisms from this microbiota was assessed. Subjects with adult periodontitis were examined clinically and microbiologically. Twenty-one subjects had a documented history of penicillin therapy within the previous 6 months whereas an additional 21 subjects had no history of antibiotic use within 1 year. Subgingival plaque samples were cultured anaerobically on nonselective and penicillin-containing elective media. MICs and beta-lactamase production were determined for the isolates from the elective medium. The penicillin-resistant microbiota consisted primarily of gram-negative organisms, including Bacteroides, Veillonella, Haemophilus, Eikenella, and Capnocytophaga species. The prevalence (P less than 0.05) and proportions (P less than 0.005) of both penicillin-resistant pigmented Bacteroides and Veillonella species were significantly greater in subjects with recent penicillin exposure. Of the penicillin-resistant genera identified, beta-lactamase production was detected in species of pigmented Bacteroides, Capnocytophaga, and Streptococcus. The prevalence of beta-lactamase-producing Bacteroides species was significantly greater in subjects with recent penicillin exposure (P less than 0.05). Of the antibiotics examined, no single agent was uniformly effective against all of the penicillin-resistant strains, but metronidazole and clindamycin were active against all of the penicillin-resistant pigmented Bacteroides strains.
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PMID:Penicillin resistance in the subgingival microbiota associated with adult periodontitis. 348 82

17 antibiotics, with potential for topical use, were tested for their activity against the human oral flora. Concentrations (mumol/l) required to inhibit 90% of test strains are presented and drug activities are compared. The total cultivable oral flora was susceptible to the tetracyclines including tetracycline itself, minocycline, doxycycline, and oxytetracycline and to erythromycin. On the other hand, actinobolin, kanamycin, neomycin, streptomycin, spiramycin, tyrothricin, vancomycin, clindamycin, and chloramphenicol were ineffective against many of the human oral anaerobic bacteria even at high concentration. Penicillin was effective at high concentrations but could not be recommended because organisms which are not inhibited by low concentrations are penicillinase producers. Carbenicillin was effective against all organisms except Actinobacillus actinomycetemcomitans. The gram-negative organisms involved in adult periodontitis were most susceptible to the tetracyclines, tyrothricin, carbenicillin and clindamycin, while those associated with localized juvenile periodontitis were susceptible to the tetracyclines or erythromycin. These data, combined with the previous findings that some tetracyclines exhibit marked substantivity and collagenase inhibition activity, indicate that tetracycline or minocycline are likely to be good choices in the treatment or prevention of oral diseases.
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PMID:Susceptibility of human oral anaerobic bacteria to antibiotics suitable for topical use. 385 75

During a three-year period, Capnocytophaga sputigena bacteremia occurred in three patients with acute leukemia receiving induction therapy on a hematology ward. Oral pathology such as periodontitis or severe mucositis was considered to be the most likely source of bacteremia. All three blood culture isolates were identified as that species by deoxyribonucleic acid (DNA) homology studies. Because of the phenotypical similarity of Capnocytophaga species, it is difficult to differentiate them by conventional bacteriological methods. All three isolates were susceptible to antibiotics active against most anaerobes. However, production of beta-lactamase was found in two isolates, one of which proved resistant to both piperacillin and ceftazidime. Therefore, the empiric use of imipenem or clindamycin may be justified in febrile granulocytopenic patients with cancer who develop significant oral lesions.
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PMID:Capnocytophaga sputigena bacteremia associated with acute leukemia. 836 May 17

In 23 untreated adult periodontitis patients, the occurrence of beta-lactamase producing periodontal bacteria was determined. In addition to non-selective isolation media, selective isolation and growth of beta-lactamase positive subgingival bacterial species was carried out on blood agar plates supplemented with amoxicillin and plates with amoxicillin+clavulanic acid. Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Peptostreptococcus micros, Fusobacterium nucleatum, Bacteroides forsythus and Campylobacter rectus isolates from the non-selective medium were tested for beta-lactamase activity by a nitrocefin disk method (DrySlide) and by a laboratory chromogenic nitrocefin-based test. Isolates from the amoxicillin plates that were absent on the amoxicillin/clavulanic acid plates were identified and tested for beta-lactamase production. Based on the non-selective plates, six of 23 P. intermedia isolates, 2 of 19 B. forsythus isolates and 3 of 23 F. nucleatum isolates were beta-lactamase positive. The beta-lactamase positive species Prevotella loescheii, Prevotella buccae, Prevotella buccalis and Actinomyces spp were recovered from the selective amoxicillin plates. beta-Lactamase positive subgingival species were recovered from 17 of 23 patients (74%) but usually comprised low proportions of the subgingival microbiota (range < 0.01-15%). Comparison of the DrySlide test and the nitrocefin-based laboratory test revealed full agreement of test results. beta-Lactamase activity in whole subgingival plaque was detected in 12 patient samples (52%). It was concluded that beta-lactamase activity in subgingival bacteria in adult periodontitis is a common feature. However, since the majority of the samples showed only low-level enzymatic activity, the clinical relevance of this observation with regard to therapy with unprotected enzyme-susceptible beta-lactams is uncertain, though failure on the other hand, is difficult to rule out when a mechanism of resistance is present. The majority of beta-lactamase positive strains was found among species of the Prevotella genus.
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PMID:beta-Lactamase producing bacteria in adult periodontitis. 926 40

The activities of the pristinamycin and its two components (RP 12536 and RP 27404) were investigated using the reference agar dilution method M11A3, on 175 anaerobic strains in comparison with that of erythromycin, clindamycin, metronidazole, amoxycillin either alone or combined with clavulanic acid, piperacillin, cefoxitin, cefotetan and cefotaxime. beta-lactamase production was detected for all the 55 B. fragilis group strains and 8/12 Prevotella and 2/18 Fusobacterium strains, respectively. On the whole anaerobes, resistance rates (%) were respectively: RP 27404 (69), RP 12536 (64), pristinamycin (5) erythromycin (31), clindamycin (17), metronidazole (7) amoxycillin (24), amoxycillin-clavulanic acid (2), piperacillin (7), cefoxitin (14), cefotetan (21) and cefotaxime (27). RP 27404 and 12536 had low activities on anaerobes but acted synergistically as pristinamycin. The greatest anti-anaerobic potencies were obtained with amoxycillin-clavulanic acid combination, pristinamycin, metronidazole and piperacillin. As resistance was not found for pristinamycin among Prevotella, Fusobacterium, Gram+ rods and Peptostreptococcus, this streptogramin may be an appropriate agent for the treatment of periodontitis, pulmonary, ENT, gynecologic and soft tissue infections where these anaerobes are frequently involved.
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PMID:[In vitro activity of 10 antibiotics including pristinamycin and its two components (RP 12536 and 27404) against strict anaerobes]. 976 28

Porphyromonas gingivalis is a gram-negative, black-pigmented, oral anaerobe strongly associated with adult periodontitis. Previous transposon mutagenesis studies with this organism were based on the Bacteroides transposon Tn4351. Characterization of Tn4351-disrupted genes by cloning has not been an efficient way to analyze large numbers of mutants and is further complicated by the high rate of cointegration of the suicide delivery vector containing Tn4351. In this study, we mutagenized P. gingivalis with a modified version of the Bacteroides fragilis transposon Tn4400. Plasmid pYT646B carrying the transposon was mobilized from Escherichia coli to P. gingivalis ATCC 33277 by conjugation. Both normal and inverse transposition frequencies were similar (3 x 10(-8)). However, the inverse transposon (Tn4400') contains a pBR322 replicon and a beta-lactamase gene; thus, the cloning of disrupted genomic DNAs from inverse transposition mutants was easily accomplished after ligation of genomic fragments and transformation into E. coli. Thousands of transconjugants could be obtained in a single mating experiment, and inverse transposition was random as demonstrated by Southern hybridization. By this procedure the disrupted genes from P. gingivalis pleiotropic mutants were quickly cloned, sequenced, and identified.
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PMID:Identification and cloning of genes from Porphyromonas gingivalis after mutagenesis with a modified Tn4400 transposon from Bacteroides fragilis. 1060 21

In a prospective study, 47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of beta-lactamase-producing strains among oral anaerobic gram-negative rods. Predominant anaerobes were identified from two of the deepest periodontal pockets. beta-Lactamase-positive strains fulfilled to at least two of three criteria: positive nitrocefin test, penicillin Etest minimal inhibitory concentration > 1 microgram/ml, and disk diffusion synergy between amoxycillin and clavulanic acid > 10 mm. At least one beta-lactamase-producing strain was found in 53.2% of patients and 39.4% of the periodontal pockets investigated. Prominent beta-lactamase-positive species were Prevotella buccae and Prevotella intermedia (respectively 16 of 38: 42% and 18 of 52: 35% positive strains), followed by Prevotella bivia, Prevotella disiens, Prevotella denticola and Fusobacterium nucleatum (respectively 1 of 6: 17%, 1 of 10: 10%, 1 of 10: 10%, and 1 of 13: 8% positive strains). No beta-lactamase producer could be evidenced in Porphyromonas gingivalis (10 strains tested). All the beta-lactamase-positive strains with the nitrocefin test had penicillin minimal inhibitory concentrations > 1 microgram/ml with the Etest, and a strong synergy between amoxicillin and clavulanic acid was always observed.
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PMID:Prevalence of beta-lactamase-producing strains among 149 anaerobic gram-negative rods isolated from periodontal pockets. 1089 90


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