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 mechanism of bacterial adherence to the mat of bacteria in preformed dental plaque is not well defined. This study measured the influence of saliva on the adherence of bacteria in suspension to a continuous bacterial surface in vitro. Twenty different pairs of bacteria were tested, consisting of Streptococcus spp., Haemophilus spp. and Actinomyces spp. The species were chosen based on the parameters of coaggregation, and salivary agglutination. The results were expressed as bacteria that adhered per mm2 of bacterial surface. When both the surface bacteria and the bacteria in suspension agglutinated in saliva, interbacterial adherence was increased 2.5-fold when a salivary coating was placed on the surface. When one or both of the bacteria did not agglutinate in saliva, interbacterial adherence was increased only slightly when the surface was saliva-coated. The results suggested that salivary-mediated adherence is significant to plaque formation once the tooth surface becomes covered with bacteria. Thus bacteria that are capable of agglutinating in saliva may have a distinct advantage in colonization of the plaque surface.
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PMID:The influence of saliva on interbacterial adherence. 747 50

Earlier studies have demonstrated that pure cultures of oral streptococci produce hydrogen peroxide but none has found any free peroxide in dental plaque or salivary sediment despite streptococci being major components of their mixed bacterial populations. The absence of peroxide in plaque and sediment could be due to the dominance of its destruction over its formation by bacterial constituents. To identify which of the oral bacteria might be involved in such a possibility, pure cultures of 27 different oral bacteria were surveyed (as well as dental plaque and sediment) for their peroxide-forming and peroxide-removing capabilities. Peroxide production was measured for each of the pure cultures by incubation with glucose at low and high substrate concentrations (2.8 and 28.0 mM) for 4 h and with the pH kept at 7.0 by a pH-stat. Removal of hydrogen peroxide was assessed in similar experiments where peroxide at 0, 29.4, 147.2 or 294.4 mM [0, 0.1, 0.5 and 1% (w/v)] replaced the glucose. Hydrogen peroxide formation was seen with only three of the bacteria tested, Streptococcus sanguis I and II (sanguis and oralis), and Strep. mitior (mitis biotype I); levels of hydrogen peroxide between 2.2 and 9.8 mM were produced when these micro-organisms were grown aerobically and 1.1 and 3.9 mM when grown anaerobically. Earlier reports indicate that such levels were usually sufficient to inhibit the growth of many plaque bacteria. The amounts formed were similar at the two glucose levels tested, suggesting that maximum peroxide production is reached at low glucose concentration. None of the three peroxide-producing organisms was able to utilize hydrogen peroxide but five of the other 24 tested, Neisseria sicca, Haemophilus segnis, H. parainfluenzae, Actinomyces viscosus and Staphylococcus epidermidis, could readily do so, as could the mixed bacteria in salivary sediment and dental plaque, both of which contain relatively high numbers of these peroxide-utilizing micro-organisms. The ability of the bacteria in plaque and sediment to degrade hydrogen peroxide was considerable and extremely rapid; peroxide removal and usually complete within the first 15 min of the incubation even when its initial level was as high as 294.4 mM. This almost overwhelming ability to remove peroxide was confirmed when peroxide-producing and -using cultures were mixed and when each of eight salivary sediments was incubated with glucose and with peroxide at concentrations up to 294.4 mM. In the glucose incubations, no hydrogen peroxide was observed, indicating dominance of microbial peroxide removers over hydrogen peroxide producers.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Bacteria in human mouths involved in the production and utilization of hydrogen peroxide. 748 77

The Macaca mulatta species of rhesus monkey is one of several non-human primate (nhp) models for periodontal disease. This report presents the bacteriology of the gingival sulci in M. mulatta monkeys. Three sub-gingival sites (maxillary right central incisor, the disto-buccal of the mandibular left second molar and mesio-buccal of the mandibular right second molar) of 9 monkeys were evaluated clinically before scaling and 7 days after scaling. Plaque samples were obtained from sub-gingival sites before clinical examination and studied bacteriologically by dark field microscopy, selective and non-selective culture, and by primary phenotypic characterizations of culture isolates. Several gingival sites presented with mild gingival inflammation. Anaerobic and facultatively anaerobic bacteria were the predominant flora colonizing the gingival sulci. The major microbial groups were Haemophilus species (100% of sites; percentage of total anaerobic count (TAC): 21-51), Peptostreptococcus micros (89%, 7.5-29.5), Actinomyces sp. (85%, 7-27), Fusobacterium nucleatum (90%, 5-8), Actinobacillus actinomycetemcomitans (73%, 1.3-12), black-pigmented anaerobic rods (BPAR) (80%, 0.6-6.5) and oral streptococci (80%, 0.2-1.0). Microbial groups detected less often were Wolinella sp. (66%, 0-2.6), Capnocytophaga sp. (30%), Eikenella corrodens (4.7%, 0), Campylobacter sp. (28%, 0-0.1) and spirochetes (4.7%, 0-0.07). Seven days after gingival sites were scaled, the plaque score and indices for gingival inflammation declined significantly. The gingival flora after scaling were characterized by lower proportions of the Actinomyces sp., P. micros and BPAR; and increased proportions of the oral streptococci, relative to pre-scaling levels.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sub-gingival microflora in Macaca mulatta species of rhesus monkey. 842 83

The aim of this double blind, cross-over, microbiological study was to compare the effect of topical application of the plaque control agent 0.5% delmopinol HCl with placebo on early supragingival plaque formation. Six subjects underwent 7 periods (0.5, 1, 2, 8 and 24 h and 3 and 7 days) of placebo and delmopinol application, respectively. At the start of each study period the teeth were professionally cleaned and 2 ml of placebo and delmopinol 0.5%, respectively, were applied on all teeth (twice daily for periods lasting 24 h or more). At the end of each period, supragingival plaque samples of one upper and one lower buccal tooth surface were collected separately and cultured on anaerobically incubated Brucella blood agar, on aerobically incubated blood agar and on selective media for the enumeration of Streptococcus spp., Haemophilus spp., Actinomyces spp., Veillonella spp., Neisseria spp. and Fusobacterium spp. The total anaerobic cultivable microflora after delmopinol use was 10-100 times lower than after placebo use. Compared with placebo, the proportion of cultivable aerobes (61.3%), Streptococcus spp. (104.8%) and Haemophilus spp. (82.3%) increased and the proportion of Actinomyces spp. (86.1%), Veillonella spp. (60.5%), Neisseria spp. (96.9%) and Fusobacterium spp. (60.6%) decreased after 7 days. Short-term application of 0.5% delmopinol HCl on supragingival dental plaque regrowth resulted in a reduction of the number of cultivable microorganisms in the plaque and produced a shift in the cultivable plaque composition.
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PMID:Microbiology of early supragingival plaque development after delmopinol treatment. 851 Sep 82

Titanium granules were tested for their antibacterial effect on strains of Streptococcus sanguis, Streptococcus mitis, Actinomyces naeslundii, Haemophilus parainfluenzae, Fusobacterium spp. and Prevotella intermedia in comparison with amalgam and two of its components, copper and tin. Glass beads were used as controls. The number of viable bacteria was estimated in samples exposed to the various materials for 1, 3, 6 and 24 h, respectively, and the viable counts were related to the baseline value. Titanium showed low antibacterial effect on the species tested. Copper and amalgam showed an expressed toxicity to all species and differed significantly from titanium and glass particles. Gram positive Streptococcus spp. and A. naeslundii showed a lower susceptibility to the metals than the Gram negative species. The antibacterial effect of copper and amalgam test particles on S. sanguis and P. intermedia was significantly decreased in the presence of serum. This study showed that some metals have a toxic effect in vitro on oral bacteria, a fact that may play a role in plaque formation when these materials are used for dental restorations. Titanium did not have a similar antibacterial effect.
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PMID:Effect of titanium on selected oral bacterial species in vitro. 874 74

The intraperitoneal immunization of Balb/c mice with subgingival plaque from advanced periodontal pockets or with certain strains of Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Actinomyces israelii, Streptococcus mitis, or Streptococcus oralis yielded frequently indistinguishable IgM monoclonal antibodies which were reactive with antigens from a variety of oral bacteria. This study aimed to characterize the specificity of such monoclonal antibodies and the diversity of oral bacteria expressing this target antigen or epitope. Using a competitive enzyme-linked immunosorbent assay to study a variety of competitor substances for their capacity to bind to the monoclonal antibodies, we identified phosphorylcholine as the recognized epitope. The concentration of positive bacteria with extraordinarily bright cell wall fluorescence in indirect immunofluorescence assays varied between 0.1% and 15% in subgingival and from 10 to 40% in supragingival plaque samples. Labeled bacteria belonged to different morphotypes, including cocci, rods, and filaments. Of 75 species tested in vitro, 14 gram-positive and four gram-negative species were found to harbor positive strains. Haemophilus aphrophilus, Streptococcus mitis, Actinomyces georgiae, Actinomyces gerencseriae, Actinomyces israelii, and Actinomyces odontolyticus were human oral species of which all tested strains were capable of binding the cross-reactive monoclonal antibodies. In contrast, Actinomyces naeslundii was consistently negative. These data provide evidence for a much more common expression of phosphorylcholine by oral bacteria than hitherto believed but do not indicate an obvious association of phosphorylcholine expression with oral health or inflammatory periodontal diseases.
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PMID:Dominant cross-reactive antibodies generated during the response to a variety of oral bacterial species detect phosphorylcholine. 1006 49

In edentulous patients, the microbial colonization of permucosal implants of sintered hydroxyapatite was studied. Samples were taken from mucosa and dentures before insertion of implants and from supra- and subgingival sites two to 10 weeks after insertion. In total, five patients and 10 implants with clinically healthy peri-implant tissues were studied. The samples were investigated by dark-field microscopy and anaerobic culture. The supragingival plaque of the implants was dominated by Gram-positive cocci and rods, the subgingival plaque by Haemophilus spp. and Veillonella parvula. A group of bacteria was found specifically related to the implants: Actinomyces odontolyticus, Peptostreptococcus micros, Haemophilus actinomycetemcomitans, Eikenella corrodens, Capnocytophaga sputigena, and Leptotrichia buccalis. Black-pigmented Bacteroides was not found in any of the examined samples. Spirochetes were observed in denture plaque samples and in supragingival plaque of the implants. It is concluded that bacteria known as potential periodontal pathogens colonize the permucosal implants in the first weeks after insertion. The presence of these species seems to be dependent on the ecological factors provided by the artificial gingival crevice of the permucosal implants in the edentulous mouth.
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PMID:Early microbial colonization of permucosal implants in edentulous patients. 1087 1

Diagnosis of erysipelas is based upon the association of an acute inflammatory plaque with fever, lymphagiitis, adenopathy and hyperleukocytosis. These associated symptoms are variable (20-70 p. 100 of cases). Bacteriology is not helpful for the diagnosis of erysipelas because of a low sensitivity (hemoculture 5 p. 100, standard examinations 5-41 p. 100), or delayed positivity (serology). Moreover cutaneous bacteriology is difficult to assess when other bacteria than streptococci are isolated. Erysipelas have to be distinguished from non-necrotizing cellulitis by peculiar clinical features (such as erysipeloid, facial staphylococcal infection, Pasteurella, Haemophilus influenzae) and from necrotizing fasciitis. Some non-infectious diseases may mimic erysipelas such as venous thrombosis, familial Mediterranean fever, prosthesis intolerance, and compartment syndrome. Because the diagnostic value of clinical symptoms is not known and no diagnostic gold standard has been established, it is impossible to be sure that non-streptococcal erysipelas (especially staphylococcal) really exists. Thus, the first line treatment for all erysipelas must be an antistreptococcal antibiotic. Before prescribing a treatment, hemoculture and blood cell count could be useful. If antistreptococcal antibiotherapy is inefficient, all the differential diagnoses must be reviewed.
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PMID:[Diagnostic criteria for erysipelas]. 1131 59

Antibodies reactive with phosphorylcholine (PC) are ubiquitous in human sera, but the antigens stimulating their production and their function are not clear. Previous studies have shown that a significant proportion of dental plaque bacteria contain PC as determined by reactivity with PC-specific mouse myeloma proteins and monoclonal antibodies. Additionally, serum antibody concentrations of immunoglobulin (IgG) G anti-PC are higher in sera of individuals who have experienced periodontal attachment loss than those who are periodontally healthy. These data implicate the oral microflora as a source of antigen-stimulating anti-PC responses. Recent data also indicate that antibodies with specificity for PC are elevated in ApoE-deficient mice, a model for studies of athersclerosis, and that such antibodies bound oxidized low-density lipoproteins (LDL) (oxLDL) in atherosclerotic plaques. These data prompted the hypothesis that human anti-PC could bind to both oral bacteria and human oxLDL, and that these antigens are cross-reactive. We therefore examined the ability of human anti-PC to bind to PC-bearing strains of oral bacteria using enzyme-linked immunosorbent inhibition assays and by assessment of direct binding of affinity-purified human anti-PC to PC-bearing Actinobacillus actinomycetemcomitans. Our results indicated that PC-bearing strains of Streptococcus oralis, Streptococcus sanguis, Haemophilus aphrophilus, Actinomyces naeslundii, Fusobacterium nucleatum, and A. actinomycetemcomitans, as well as a strain of Streptococcus pneumoniae, absorbed up to 80% of anti-PC IgG antibody from human sera. Furthermore, purified anti-PC bound to a PC-bearing strain of A. actinomycetemcomitans but only poorly to a PC-negative strain. OxLDL also absorbed anti-PC from human sera, and oxLDL but not LDL reacted with up to 80% of the anti-PC in human sera. Furthermore, purified anti-PC bound directly to oxLDL but not to LDL. The data indicate that PC-containing antigens on a variety of common oral bacteria are cross-reactive with neoantigens expressed in oxLDL. We propose that PC-bearing dental plaque microorganisms may induce an antibody response to PC that could influence the inflammatory response associated with atherosclerosis.
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PMID:Phosphorylcholine-dependent cross-reactivity between dental plaque bacteria and oxidized low-density lipoproteins. 1159 29

Dental plaque samples from 40 children were screened for the presence of bacteria resistant to amoxicillin. Fifteen children had used amoxicillin and 25 had not used any antibiotic in the 3 months prior to sample collection. All (100%) of the children harbored amoxicillin-resistant oral bacteria. The median percentage of the total cultivable oral microbiota resistant to amoxicillin was 2.4% (range, 0.1 to 14.3%) in children without amoxicillin use and 10.9% (range, 0.8 to 97.3%) in children with amoxicillin use, with the latter value being significantly higher (P < 0.01). A total of 224 amoxicillin-resistant bacteria were isolated and comprised three main genera: Haemophilus spp., Streptococcus spp., and Veillonella spp. The biodiversity of the amoxicillin-resistant microbiota was similar among the isolates from children with and without previous antibiotic use. The amoxicillin MIC at which 90% of the isolates were inhibited for isolates from children who had used amoxicillin in the previous 3 months was higher (64 mg liter(-1)) than that obtained for the isolates from subjects who had not used antibiotics (16 mg liter(-1)). The majority of the amoxicillin-resistant isolates (65%) were also resistant to at least one of the three antibiotics tested (penicillin, erythromycin, and tetracycline), with resistance to penicillin (51% of isolates) being the most frequently encountered. However, significantly more (P < 0.05) of the amoxicillin-resistant isolates from subjects with previous amoxicillin use were also resistant to erythromycin. This study has demonstrated that a diverse collection of amoxicillin-resistant bacteria is present in the oral cavity and that the number, proportions, MICs, and resistance to erythromycin can significantly increase with amoxicillin use.
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PMID:Effect of amoxicillin use on oral microbiota in young children. 1527 96


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