Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The in vitro susceptibility of Actinobacillus actinomycetemcomitans to azithromycin, a new macrolide antibiotic of a new class known as azalides, was compared with that of erythromycin by the agar dilution method on Mueller-Hinton Haemophilus test medium. Eighty-two A. actinomycetemcomitans strains, 79 recent clinical isolates obtained from 40 periodontally healthy or diseased subjects, and 3 type strains were included in the study. Erythromycin showed poor in vitro activity against A. actinomycetemcomitans. Azithromycin, however, was highly effective against A. actinomycetemcomitans: all strains were inhibited at 2.0 micrograms/ml. Azithromycin exhibited the best in vitro activity against the serotype a subpopulation of A. actinomycetemcomitans: 100% of the strains were inhibited at 1.0 micrograms/ml. The lowest MICs were, however, recorded by serotype b strains. Since azithromycin has favorable pharmacokinetic properties, including excellent distribution into tissues, it could be expected to pass into gingival crevicular fluid at levels sufficient to inhibit A. actinomycetemcomitans in vivo. Therefore, it is a good candidate for future clinical trials in A. actinomycetemcomitans-associated periodontitis.
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PMID:In vitro activity of azithromycin compared with that of erythromycin against Actinobacillus actinomycetemcomitans. 132 17

The prevalence and distribution of Haemophilus actinomycetemcomitans (H.a.) were studied in 3292 specimens of subgingival plaque on the four subgingival aspects of all teeth of the dental arch, 150 specimens from the mucosal surface (tongue and cheek) and 30 saliva specimens in 30 subjects. The sample population of 30 subjects was subdivided into three groups: 10 normal subjects, 10 subjects with localised juvenile periodontitis (SLJP) and 10 subjects with adult chronic periodontitis (SACP). The prevalences of H.a. in subgingival areas of each group mentioned were 30%, 90% and 60% respectively. Scores for prevalence obtained with other types of specimens proved to be lower except for saliva specimens which appear to be a less representative marker of subgingival prevalence of H.a.. Histograms for the distribution of H.a. revealed a predominance of this microorganism on the proximal surface of molar teeth in the three groups of patients. Only the SLJP also exhibited a high prevalence on the proximal aspect of the incisor teeth. The wide distribution of H.a. in all of the clinical groups studied suggests that this bacterium is not a good marker of periodontal disease and that it is necessary to define the most characteristic phenotypes and genotypes.
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PMID:[The distribution and prevalence of Haemophilus actinomycetemcomitans in the oral cavity]. 193 44

Seven juvenile periodontally diseased patients were evaluated for clinical, microbiologic and local or systemic host factors. Three patients showed the localized from of periodontitis clinically and radiographically and by deep periodontal pockets associated with the molars and incisors. Four were in the generalized froms, in which in most cases all teeth were affected. The results in both diseased froms on the predominant cultivable subgingival microflora, the composition of which was not different from that in adult periodontitis, consisted of significantly increased proportions of Gram-negative anaerobic rods, Bacteroides sp. and B. gingivalis, Haemophilus sp. and H. actinomycetemcomitans were detected in 1/3 of the localized and 2/4 of the generalized periodontitis. They were of no value in distinguishing activity that enhanced disease in the generalized from. Elevated serum IgG responses were noted with B. gingivalis. No markedly functional abnormalities of neutrophils from peripheral blood have been demonstrated, however it might function with systemic factors, like an insulin-dependent diabetes. Morphologic characteristics of the oral and periodontal tissue in localized periodontitis were that the pattern of destruction was confined to specific teeth groups characterized by extensive the bucco-lingual width ratio of the dental crown to alveolar bone width. These observations indicate that the generalized form of juvenile periodontitis lesions were associated not only with the presence of subgingival bacteria, but also with conditions such as local morphologic and systemic or constitutional factors, individual variation in relation to destructive and protective aspects of the defense mechanisms.
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PMID:[The clinical and etiological study on juvenile periodontal disease]. 213 90

Analysis of the subgingival microflora has recently implicated Actinobacillus (Haemophilus) actinomycetemcomitans and several black Bacteroides species in the aetiology of juvenile, adult and rapidly progressing periodontitis. Rapid bacteriological diagnosis has been hampered by the slow growth and fastidious nature of these bacteria. To construct diagnostic probes, dideoxy sequencing of the 16S rRNA molecules from A. (H.) actinomycetemcomitans, Haemophilus aphrophilus, Bacteroides gingivalis, Bacteroides intermedius subgroup II, Bacteroides asaccharolyticus and several closely related species was performed. Next, oligodeoxynucleotides, complementary to defined regions of the 16S rRNA exhibiting considerable evolutionary divergence, were synthesized for use as molecular probes. In a dot-blot hybridization assay, all strains from each of the species for which probes were constructed were correctly identified, with a detection limit of less than 5 x 10(3) organisms. No cross-hybridization to closely related species (except for H. aphrophilus and Haemophilus paraphrophilus) or contaminating bacteria was observed. Using a modified DNA/RNA hybridization technique, the detection could be performed in less than 12 h, as compared to 2-3 weeks using conventional bacteriological procedures.
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PMID:Synthetic oligodeoxynucleotide probes for the rapid detection of bacteria associated with human periodontitis. 246 76

Pathophysiological features were studied on 7 patients with rapidly progressive periodontitis but without any evidence of systemic disease, to analyse the clinical pathogenesis. The patients consisted of 5 females, 2 males, between the ages of 32 and 42 years. All patients had severe and rapid alveolar bone destruction on the basis of radiographic measurement. Abnormal serum levels of IgG and IgM were detected in some patients. Higher IgG level was found in 4 patients and higher IgM level was found in 2 patients. The proportion of lymphocyte subsets was calculated in mononuclear cells from peripheral blood of patients. Higher OKT4/OKT8 ratio was found in all patients. The percentage of OKT4 positive cells in 2 patients was higher than that in normal subjects while the percentage of OKT8 positive cells in 4 patients was lower than that in the healthy controls. Microorganisms from periodontal pockets were examined in 5 patients. Bacteriodes was isolated in all 5 patients and Haemophilus actinomycetemcomitans in 2 patients.
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PMID:[Pathophysiological analysis of rapidly progressive periodontitis]. 257 29

Whole Gram-negative bacteria associated with juvenile and adult periodontitis, and their respective extracted lipopolysaccharides (LPS), were tested for the ability to activate quiescent human peripheral blood monocytes. All pathogenic Gram-negative bacteria and all LPS tested were able to induce the production of significant amounts of IL-1 and TNF, monokines known to induce osteoclastic bone resorption. Haemophilus segnis, which has not been associated with any form of periodontal disease, did not activate monocytes. Purified LPS from Actinobacillus actinomycetemcomitans Y4 was able to elicit IL-1 and TNF release at a threshold concentration of 1-10 ng/mL. To examine the mechanism whereby whole bacteria activated monocytes, we added polymixin B in culture with glutaraldehyde-fixed bacteria to bind LPS. This resulted in the abrogation of IL-1 and TNF production. To compare the effects of Gram-positive oral bacteria on monocytes, we also tested Staphylococcus epidermidis and the Gram-positive amphipathic equivalent of LPS, lipoteichoic acid (LTA) extracted from Staphylococcus aureus bacteria. Whereas whole Gram-positive bacteria had no stimulatory effect on monocytes, LTA induced IL-1 and TNF production at a concentration range equivalent to that of the LPS. These results indicate that monocytes are activated by free LPS or LPS bound to Gram-negative pathogenic periodontal bacteria to produce monokines which may contribute to the destruction of periodontal bone.
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PMID:Production of interleukin-1 and tumor necrosis factor by human peripheral monocytes activated by periodontal bacteria and extracted lipopolysaccharides. 326 3

The subgingival microflora and serum antibody response was examined in periodontitis patients with noninsulin-dependent diabetes mellitus (NIDDM), impaired glucose tolerance (IGT), and normal glucose tolerance (NGT). The predominant cultivable microflora was determined for subgingival plaque sampled from two deep periodontal pockets in each of eight adult periodontitis patients with NIDDM. Indirect immunofluorescence for Bacteroides intermedius, Bacteroides gingivalis, and Haemophilus actinomycetemcomitans was used to examine these same samples as well as 186 additional subgingival plaque samples from 47 patients with moderate to severe generalized periodontitis including 25 subjects with NIDDM, six subjects with IGT, and 16 subjects with NGT. Serum antibody levels to 13 microorganisms including seven oral bacterial species and one nonoral control species were measured by enzyme-linked immunosorbent assays (ELISA) in 377 subjects including 84 normal subjects without periodontal disease, 112 normal subjects with periodontitis, 19 periodontally normal subjects with IGT, 65 periodontitis patients with IGT, 15 periodontally normal subjects with NIDDM, and 82 periodontitis patients with NIDDM. Three hundred eighty-two bacterial isolates were recovered from the eight patients. B. intermedius was the most frequently isolated microorganism constituting 16% of the total isolates followed by Wolinella recta and B. gingivalis, which each accounted for 13% of the total. Streptococcus sanguis was the most prevalent microorganism, which was found in 75% of the sites. Subgingival plaque samples examined by immunofluorescence demonstrate a high prevalence of black-pigmented Bacteroides and suggest that the proportion of B. gingivalis but not B. intermedius is higher in NIDDM with periodontitis than in other groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Microbiological and immunological studies of adult periodontitis in patients with noninsulin-dependent diabetes mellitus. 327 68

Invasion of periodontal tissues by different bacterial morphotypes has been reported in human periodontitis; however, limited information is available as to prevalence, localization and the bacterial species involved. The present study determined prevalence and gingival localization of Actinobacillus (Haemophilus) actinomycetemcomitans in periodontal lesions of juvenile periodontitis patients. Thirty-five gingival biopsies were obtained from 12 juvenile periodontitis patients at the time of periodontal therapy. One additional control biopsy was obtained from each of two adult periodontally healthy subjects, one adult periodontitis patient and one periodontally healthy monkey (Macaca fosibolius). The biopsies were carefully processed to avoid mechanical introduction of bacteria into the tissues and were examined using light and electron microscopy. Rabbit antisera specific for the three A. actinomycetemcomitans serotypes were used for immunofluorescence microscopic localization of A. actinomycetemcomitans antigens in the gingival sections. Immunofluorescence microscopy showed A. actinomycetemcomitans specific antigens in the gingival tissues of 11 of the 12 juvenile patients examined. None of the control specimens showed evidence of A. actinomycetemcomitans antigens in the gingival connective tissue. One specimen from a periodontally healthy subject and the monkey biopsy, however, showed A. actinomycetemcomitans antigens in bacterial plaque on the surface of the crevicular epithelium. Transmission electron microscopic examination showed microcolonies of small gram-negative rods in the connective tissue, as well as single bacterial cells between collagen fibers and in areas of cell debris. In addition to these extracellular bacterial cells, evidence of bacterial cells was also found within gingival connective tissue phagocytic cells. The data from the present study suggest that the gingival tissue in juvenile periodontitis lesions harbors A. actinomycetemcomitans.
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PMID:Tissue localization of Actinobacillus actinomycetemcomitans in human periodontitis. I. Light, immunofluorescence and electron microscopic studies. 330 56

The goal of this study was to relate attachment loss patterns in early onset periodontitis subjects (juvenile periodontitis n = 47 and severe (generalized) periodontitis n = 52) with antibody reactivities to 25 bacterial strains which were suspected periodontal pathogens. The 25 antibody reactivities were screened by correlation analysis. Eleven strains were found to be significantly related to attachment loss. Using these 11 reactivities, stepwise multiple linear regression with plaque and age as covariates was used to further relate the reactivities within each subject group. Plaque was significantly related to the number of teeth with slight, moderate, or severe attachment loss. A significant inverse relationship was found between antibody reactivity with Haemophilus actinomycetemcomitans Y4 and the number of teeth having slight or moderate attachment loss. Similarly a significant inverse relationship between antibody reactivity with Bacteroides gingivalis and the number of teeth having moderate or severe attachment loss was found. The inverse relationship between the two antibody reactivities and attachment loss patterns were independent of the positive relationship of plaque. These relationships suggest that the failure to mount a substantial antibody response to these organisms leads to greater and more widespread periodontal disease in early onset periodontitis subjects.
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PMID:Relationship of serum antibody to attachment level patterns in young adults with juvenile periodontitis or generalized severe periodontitis. 347 25

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


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