Database: EMBASE <: international biomedical and pharmaceutical literature, 1988 - Jun 2000. [Trial access until 3/2001. Feedback welcome to medical.library@umich.edu] Search Strategy (You Saved Citations 1-51 From Set 64): ----------------------------------------------------------------------------- 1 "S.".mp. 204485 2 "Str.".mp. 1164 3 strep:.mp. 58892 4 exp Streptococcus/ 19839 5 or/1-4 256574 6 sanguis.mp. 566 7 sanguinis.mp. 29 8 mitis.mp. 370 9 oralis.mp. 459 10 crista.mp. 375 11 mitior.mp. 16 12 gordonii.mp. 201 13 or/6-12 1739 14 5 and 13 1017 15 Streptococcus sanguis/ 373 16 14 or 15 1017 17 exp Tooth demineralization/ 7624 18 demineralization.mp. 889 19 caries.mp. 1810 20 caires.mp. 0 21 craies.mp. 0 22 careis.mp. 1 23 carise.mp. 0 24 (teeth adj3 cavit:).mp. 32 25 (tooth adj3 cavit:).mp. 31 26 (dental adj3 cavit:).mp. 54 27 (dentin adj3 cavit:).mp. 14 28 (enamel adj3 cavit:).mp. 6 29 (teeth adj3 decay:).mp. 59 30 (tooth adj3 decay:).mp. 58 31 (dental adj3 decay:).mp. 47 32 (dentin adj3 decay:).mp. 0 33 (enamel adj3 decay:).mp. 1 34 (active adj decay).mp. 5 35 (rampant adj3 decay:).mp. 4 36 (recurrent adj3 decay:).mp. 3 37 (white adj spot:).mp. 226 38 carious.mp. 110 39 cariology.ti,ab. 2 40 (non-cavitated adj3 lesion:).mp. 0 41 (noncavitated adj3 lesion:).mp. 1 42 Tooth remineralization/ 800 43 (dental adj3 fissure:).mp. 7 44 (tooth adj3 fissure:).mp. 3 45 (teeth adj3 fissure:).mp. 1 46 caries-free.mp. 28 47 cariesfree.mp. 0 48 Cariogenic agents/ 3 49 precavit:.mp. 2 50 (filled adj3 teeth).mp. 46 51 (filled adj3 tooth).mp. 9 52 (oral adj fissure:).mp. 4 53 (tooth adj3 remineraliz:).mp. 1 54 (teeth adj3 remineraliz:).mp. 4 55 dft.mp. 560 56 dfs.mp. 992 57 dmf:.mp. 1254 58 cariogeni:.mp. 166 59 or/17-58 12451 60 Dental plaque/ 818 61 ((tooth or teeth or dent:) adj3 (placque or plaque)).mp. 950 62 or/59-61 12522 63 16 and 62 134 64 limit 63 to (human and english language) 51 65 from 64 keep 1-51 51 66 from 64 keep 1-51 51 *************************** <1> UI - 2000120309 AU - Gong K AU - Mailloux L AU - Herzberg MC IN - M.C. Herzberg, Department of Preventive Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455; United States. E-Mail: mcherzb@tc.umn.edu. TI - Salivary film expresses a complex, macromolecular binding site for Streptococcus sanguis. SO - Journal of Biological Chemistry 24 MAR 2000Vol 275(12) (pp 8970-8974), 2000. AB - Teeth in the oral cavity are coated with a salivary film or pellicle, which lacks apparent intermolecular organization. This heterogeneous film facilitates binding of early commensal colonizing bacteria, including Streptococcus sanguis. To test the hypothesis that sufficient intermolecular organization exists in salivary films to form binding sites for S. sanguis, an in vitro model of saliva-coated teeth was probed with murine anti- idiotypical monoclonal antibodies (mAb2, anti-ids). The anti-ids were harvested from hybridomas that were developed in response to first generation murine hybridomas that produced anti-S. sanguis adhesin monoclonal antibodies (mAb1). The anti-ids (i) reacted with experimental salivary films and inhibited S. sanguis adhesion in a dose-dependent fashion. In Western blots, the anti-ids (ii) recognized a high molecular weight salivary antigen and (iii) secretory IgA (sIgA) light chain and alpha-amylase. After isolation by gel filtration from whole saliva or mixed secretory IgA and alpha-amylase, the high molecular weight component, containing amylase activity and sIgA, bound to hydroxyapatite to promote adhesion of S. sanguis. Therefore, a complex enriched in secretory immunoglobulin A and alpha-amylase forms a S. sanguis- binding site. [References: 29] <2> UI - 2000089991 AU - Pollanen MT AU - Salonen JI AU - Grenier D AU - Uitto V-J IN - Dr. M.T. Pollanen, Institute of Dentistry, University of Turku; Finland. E-Mail: marja.pollanen@utu.fi. TI - Epithelial cell response to challenge of bacterial lipoteichoic acids and lipopolysaccharides in vitro. SO - Journal of Medical Microbiology Vol 49(3) (pp 245-252), 2000. AB - Accumulating dental plaque at the gingival margin contains lipoteichoic acids (LTAs) from the cell walls of gram-positive bacteria. In subgingival plaque associated with periodontal disease the amount of lipopolysaccharides (LPSs) from gram-negative bacteria increases. As the gingival junctional epithelium (JE) is an important structural and functional tissue, participating in the first line defence against apical advancement of dental plaque, this study examined the direct effects of LTAs (from Streptococcus mutans and S. sanguis) and LPSs (from Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Escherichia coli) on two epithelial cell lines (HaCaT and ERM) and a culture model for human JE. The cells were exposed to the LTAs or LPSs (10-50 mug/ml) for variable periods of time. None of the bacterial surface components had any effect on primary adhesion or on the epithelial attachment of the JE cultures. However, cell growth and mitotic activity were consistently reduced in all cultures treated with LTAs. In contrast, LPSs showed only slight or no effects on cell growth and mitotic activity depending on the epithelial cells used. This suggests that LPSs, despite their established role as modulators of inflammation, do not have direct harmful effects - at the concentrations found in dental plaque and gingival crevicular fluid - which would explain the mechanism of epithelial degeneration and detachment from the tooth surface. However, the LTAs appear to inhibit the renewal of epithelium and may thus contribute to degeneration of coronal JE and subgingival colonisation by periodontal pathogens. [References: 57] <3> UI - 2000073416 AU - Love RM AU - McMillan MD AU - Park Y AU - Jenkinson HF IN - H.F. Jenkinson, Dept. of Oral and Dental Science, University of Bristol Dental School, Lower Maudlin St., Bristol BS1 2LY; United Kingdom. E-Mail: howard.jenkinson@bristol.ac.uk. TI - Coinvasion of dentinal tubules by Porphyromonas gingivalis and Streptococcus gordonii depends upon binding specificity of streptococcal antigen I/II adhesin. SO - Infection & Immunity Vol 68(3) (pp 1359-1365), 2000. AB - Cell wall-anchored polypeptides of the antigen I/II family are produced by many species of oral streptococci. These proteins mediate adhesion of streptococci to salivary glycoproteins and to other oral microorganisms and promote binding of cells to collagen type I and invasion of dentinal tubules. Since infections of the root canal system have a mixed anaerobic bacterial etiology, we investigated the hypothesis that coadhesion of anaerobic bacteria with streptococci may facilitate invasive endodontic disease. Porphyromonas gingivalis ATCC 33277 cells were able to invade dentinal tubules when cocultured with Streptococcus gordonii DL1 (Challis) but not when cocultured with Streptococcus mutans NG8. An isogenic noninvasive mutant of S. gordonii, with production of SspA and SspB (antigen I/II family) polypeptides abrogated, was deficient in binding to collagen and had a 40% reduced ability to support adhesion of P. gingivalis. Heterologous expression of the S. mutans SpaP (antigen I/II) protein in this mutant restored collagen binding and tubule invasion but not adhesion to P. gingivalis or the ability to promote P. gingivalis coinvasion of dentin. An isogenic afimbrial mutant of P. gingivalis had 50% reduced binding to S. gordonii cells but was unaffected in the ability to coinvade dentinal tubules with S. gordonii wild- type cells. Expression of the S. gordonii SspA or SspB polypeptide on the surface of Lactococcus lactis cells endowed these bacteria with the abilities to bind P. gingivalis, penetrate dentinal tubules, and promote P. gingivalis coinvasion of dentin. The results demonstrate that collagen-binding and P. gingivalis-binding properties of antigen I/II polypeptides are discrete functions. Specificity of antigen I/II polypeptide recognition accounts for the ability of P. gingivalis to coinvade dentinal tubules with S. gordonii but not with S. mutans. This provides evidence that the specificity of interbacterial coadhesion may influence directly the etiology of pulpal and periapical diseases. [References: 47] <4> UI - 1999389364 AU - Chiu B IN - Dr. B. Chiu, Dept. of Lab. Medicine-Pathology, St. Michael's Hospital, 30 Bond St, Toronto, Ont. M5B 1W8; Canada. TI - Multiple infections in carotid atherosclerotic plaques. SO - American Heart Journal Vol 138(5 II) (pp S534-S536), 1999. AB - Background: Chlamydia pneumoniae, cytomegalovirus, herpes simplex virus, and recently, periodontal disease, have been associated with human atherosclerosis. Porphyromonas gingivalis and Streptococcus sanguis are major pathogens associated with periodontitis, a common chronic inflammatory condition in adults. Investigators have found that these infectious agents may influence vascular cell functions by inducing thrombus formation, vascular cell proliferation, apoptosis, and cell death. Methods and Results: The main purpose of our study was to investigate the relation between the presence of multiple infectious agents in human carotid endarterectomy specimens and pathoanatomic features of the corresponding carotid plaques. Histologically, plaque rupture of the fibrous cap and communication of the luminal thrombus with the central necrotic lipid core was seen in or at proximity to the macrophage-rich shoulder (unstable plaque region). Thrombus within the lipid core without plaque rupture was occasionally found near the internal elastic lamina, associated with increased vascularity and lymphocytic infiltrate. Apoptosis, as detected by both the immunohistochemical staining of apoptosis-related proteins and in situ labeling of internucleosomally degraded DNA, was common in atherosclerotic plaques. Immunostainings for C pneumoniae, cytomegalovirus, herpes simplex virus-1, P gingivalis, and S sanguis were positive in the carotid plaques. From 1 to 4 organisms were found in the same specimen. The micro-organisms were immunolocalized in plaque shoulders and lymphohistiocytic infiltrate, associated with ulcer and thrombus formation, and adjacent to areas of strong labeling for apoptotic bodies. Conclusions: Our data provide evidence that multiple infectious agents may be found in atherosclerotic plaques, and sometimes in the same specimen. The current study is the first to report the detection of 2 major odontopathogens, P gingivalis and S sanguis, in atherosclerotic plaques. The immunolocalization of these micro-organisms within unstable plaque regions and their association with plaque ulceration, thrombosis, and apoptosis in vascular cells are intriguing. Multiple infectious agents may alter vascular cell function and provide a 'trigger' for acute ischemic stroke events. Further evidence from human studies and animal models will be needed. [References: 26] <5> UI - 1999298544 AU - Schenkein HA AU - Gunsolley JC AU - Best AM AU - Harrison MT AU - Hahn C-L AU - Wu J AU - Tew JG IN - H.A. Schenkein, VCU School of Dentistry, MCV Station Box 980566, Richmond, VA 23298; United States. E-Mail: hschenke@hsc.vcu.edu. TI - Antiphosphorylcholine antibody levels are elevated in humans with periodontal diseases. SO - Infection & Immunity Vol 67(9) (pp 4814-4818), 1999. AB - Human immunoglobulin G2 (IgG2) serum concentrations and the IgG2 antibody response to Actinobacillus actinomycetemcomitans can be influenced by genes, by environmental factors such as smoking, and by periodontal disease status. Examination of the IgG2 response to phosphorylcholine (PC), a response thought to be mainly induced by the C polysaccharide of Streptococcus pneumoniae, suggested that periodontal disease status was also associated with this response. This prompted the hypothesis that PC is an important oral antigen associated with organisms in the periodontal flora and that anti-PC antibody is elevated as a consequence of periodontal disease. Subjects in various periodontal disease diagnostic categories in which attachment loss is exhibited were tested for anti-PC in serum. Those with adult periodontitis, localized juvenile periodontitis, generalized early- onset periodontitis, and gingival recession all had similar levels of anti-PC IgG2 serum antibody which were significantly greater than in the group of subjects with no attachment loss. Analysis of plaque samples from subgingival and supragingival sites in all diseases categories for reactivity with the anti-PC specific monoclonal antibody TEPC-15 revealed that a substantial proportion of the bacteria in dental plaque (30 to 40%) bear PC antigen; this antigen was not restricted to morphotypes resembling only cocci but was also present on rods and branched filamentous organisms. We found that S. mitis, S. oralis, and S. sanguis, as well as oral actinomycetes, including A. viscosus, A. odontolyticus, and A. israelii, incorporated substantial amounts of [3H]choline from culture media. Further analysis of antigens derived from these organisms by Western blot indicated that S. oralis, S. sanguis, A. viscosus, A. odontolyticus, and A. israelii contained TEPC15-reactive antigens. The data show that many commonly occurring bacterial species found in dental plaque contain PC antigen and that immunization with plaque-derived PC antigens as a consequence of inflammation and periodontal attachment loss may influence systemic anti-PC antibody concentrations. [References: 27] <6> UI - 1999182305 AU - Saini S AU - Mahajan A AU - Sharma JK AU - Arora AU - Saini OP IN - Dr. S. Saini, Department of Microbiology, Postgraduate Inst. of Medical Sci., Rohtak-124001 (Haryana); India. TI - Polymicrobial etiology of dental caries. SO - Indian Journal of Pathology & Microbiology Vol 42(1) (pp 25-29), 1999. AB - The present study was carried out to establish the normal bacterial oral flora and the aerobic and anaerobic bacterial flora from deep seated dental caries, and to determine the antimicrobial sensitivity of the clinical isolates so obtained Streptococcus mutans (48%) and Streptococcus sanguis (20%) were the main aerobic isolates whereas Lactobacillus spp. (52%), Veillonella spp. (24%) and Actinomyces spp. (12%) were the major anaerobic isolates. Hundred percent of the samples from dental caries yielded polymicrobial isolates while in two samples from healthy individuals S. mutans was the sole isolate. As the flora changed from healthy tooth to dental caries it changed from one predominated by anaerobic gram-positive cocci to anaerobic gram-positive bacili. All the anaerobes isolated were sensitive to metronidazole and cefotaxime, whereas all the isolated streptococci were sensitive to penicillin, erythromycin and clindamycin. Incorporation of the antibiotics in baseline restoration, if technically feasible, has been advocated. [References: 12] <7> UI - 1999164046 AU - Leke N AU - Grenier D AU - Goldner M AU - Mayrand D IN - D. Grenier, Groupe Recherche/Ecologie Buccale, Faculte de Medecine Dentaire, Universite Laval, Laval, Que. G1K 7P4; Canada. E-Mail: Daniel.Grenier@greb.ulaval.ca. TI - Effects of hydrogen peroxide on growth and selected properties of Porphyromonas gingivalis. SO - FEMS Microbiology Letters Vol 174(2) (pp 347-353), 1999. AB - In this study we first evaluated the effects of hydrogen peroxide (H2O2) on growth and selected properties of Porphyromonas gingivalis, and compared them with those obtained by a reducing agent (cysteine). The growth of P. gingivalis was only moderately affected when H2O2 was added at concentrations up to 30 mM in a complex culture medium. However, when a defined basal medium was used, H2O2 at a concentration of 3 mM completely inhibited growth of P. gingivalis. Incorporation of cysteine at concentrations up to 30 mM in both media had no effect on growth. The effects of H2O2 and cysteine on cell-associated hemagglutinating and Arg-gingipain activities were evaluated using bacteria grown in the complex culture medium. Both activities were strongly decreased when H2O2 was added in the assay mixtures. This inhibitory effect of H2O2 was reversible. On the other hand, including cysteine in the assay mixtures increased both activities. H2O2 and cysteine had no effect on the expression of heat shock protein (HSP)-68 and HSP-75 by P. gingivalis, as determined by SDS-PAGE and Western immunoblotting analysis. In the second part of the study, we tested whether growth of selected oral bacterial species may modify the oxidation-reduction potential (Eh) of the environment. It was found that certain species were able to either decrease (P. gingivalis, Fusobacterium nucleatum, Peptostreptococcus micros, Streptococcus mutans) or increase (Streptococcus sanguis) the Eh of the medium. Our study provides evidence that an oxidizing agent such as H2O2 may affect the biology of P. gingivalis. Moreover, growth of some members of the oral microflora can generate oxidizing and reducing conditions, and thus potentially influence the ecology of subgingival sites by affecting strictly anaerobic bacteria such as P. gingivalis. Copyright (C) 1999 Federation of European Microbiological Societies. [References: 21] <8> UI - 1999085211 AU - Larsen T AU - Fiehn N-E AU - Gutschik E AU - Bangsborg JM IN - T. Larsen, Department of Oral Microbiology, School of Dentistry, University of Copenhagen, Norre Alle 20, DK-2200 Copenhagen N; Denmark. E-Mail: tl@odont.ku.dk. TI - Current status of taxonomic groups of oral streptococci in endocarditis. Can virulence factors discriminate between endocarditis and non-endocarditis strains?. SO - Clinical Microbiology & Infection Vol 5(2) (pp 73-77), 1999. AB - Objective: Infective endocarditis is frequently caused by oral streptococci, especially Streptococcus sanguis. In this group, many strains have recently been reclassified on the basis of new taxonomic schemes. The purpose of this study was to classify oral streptococci from patients with infective endocarditis and, further, to assess the importance of specific virulence factors for the development of streptococcal endocarditis. Methods: Twenty-eight previously identified and 10 new streptococcal isolates from infective endocarditis were classified according to Kilian et al and compared to 30 streptococcal isolates from the oral cavities of periodontal patients without endocarditis. Subsequently, surface hydrophobicity was assessed by hydrophobic interaction chromatography, production of extracellular dextran was determined by precipitation, and non-specific proteolytic activity was evaluated by determination of hydrolysis of gelatin, and casein-precipitating activity. Results: Eight streptococcal species were represented in the endocarditis isolates. Most strains were highly hydrophobic and none showed non-specific proteolytic activity. Dextran was produced with similar frequency in endocarditis and non-endocarditis isolates. Conclusions: The present study showed that infective endocarditis may be caused by a variety of oral streptococcal species. The possible virulence factors investigated were found in the same proportions in endocarditis acid non-endocarditis isolates, and thus did not seem to be crucial for development of endocarditis. [References: 37] <9> UI - 1998348366 AU - Pratten J AU - Smith AW AU - Wilson M IN - J. Pratten, Department of Microbiology, Eastman Dental Institute, University of London, 256 Grays Inn Road, London WC1X 8LD; United Kingdom. TI - Response of single species biofilms and microcosm dental plaques to pulsing with chlorhexidine. SO - Journal of Antimicrobial Chemotherapy Vol 42(4) (pp 453-459), 1998. AB - The aim of this study was to determine the effect of pulsing chlorhexidine gluconate, at concentrations commonly used in mouthwashes, on Streptococcus sanguis biofilms and microcosm dental plaques in vitro. Biofilms were grown on bovine enamel and nutrients were supplied in the form of artificial saliva. Pulsing experiments were carried out on steady-state biofilms using 0.05 or 0.2% chlorhexidine solutions delivered twice daily for 1 min. In a separate study, the enamel discs on which the biofilms were formed were pre-treated with chlorhexidine and pulsed directly after inoculation and then at regular intervals. With both concentrations of chlorhexidine used, a c.2 log10 reduction in the viable counts of S. sanguis was achieved with the initial pulse, but as pulsing continued, the bacterial population recovered, albeit not to the previous level. A c.1 log10 reduction in the total viable counts of the microcosm plaques was seen after the first pulse with 0.2% chlorhexidine. The total count then recovered rapidly and, after the fifth pulse, the total viable counts were not significantly different from those before pulsing. The total counts then remained at a similar level throughout the course of the experimental runs. Pre-treatment of the enamel discs with 0.2% chlorhexidine before inoculation produced viable counts of c.105 cfu/mm2, a 1 log10 reduction compared with untreated discs. After pulsing with 0.2% chlorhexidine at 8 h, a 3 log10 reduction was seen in the total aerobic and anaerobic counts, but again the viable counts subsequently increased despite twice-daily chlorhexidine pulsing. Regardless of the nature of the biofilm, pulsing initially achieved substantial kills, but the viability of the biofilms subsequently increased despite continued pulsing. Chlorhexidine was effective at reducing the viability of microcosm plaques when it was applied to the substratum before exposure to bacteria and subsequently pulsed on to the biofilms. [References: 19] <10> UI - 1998310243 AU - Ong G AU - Barr JG AU - Savage M IN - G. Ong, Royal Victoria Hospital, Belfast Link Labs, Belfast 1NK AB8; United Kingdom. TI - Streptococcus mitis: Urinary tract infection in a renal transplant patient [6]. SO - Journal of Infection Vol 37(1) (pp 91-92), 1998. <11> UI - 1998170552 AU - Rogers JD AU - Haase EM AU - Brown AE AU - Douglas CWI AU - Gwynn JP AU - Scannapieco FA IN - F.A. Scannapieco, Department of Oral Biology, School of Dental Medicine, State University New York at Buffalo, Buffalo, NY 14214; United States. TI - Identification and analysis of a gene (abpA) encoding a major amylase-binding protein in Streptococcus gordonii. SO - Microbiology Vol 144(5) (pp 1223-1233), 1998. AB - Oral streptococci such as Streptococcus gordonii bind the abundant salivary enzyme alpha-amylase. This interaction may be important in dental plaque formation and metabolism, thus contributing to the initiation and progression of dental caries and periodontal disease, the two most common plaque-mediated diseases. The conjugative transposon Tn916 was used to insertionally inactivate gene(s) essential to the expression of amylase-binding components of S. gordonii Challis, and a mutant deficient in amylase-binding (Challis Tn1) was identified. While wild-type strains of S. gordonii released both 20 kDa and 82 kDa amylase-binding proteins into culture supernatants, Challis Tn1 expressed the 82 kDa but not the 20 kDa protein. The 20 kDa amylase-binding protein was isolated from culture supernatants of S. gordonii Challis by hydroxyapatite chromatography. A partially purified, functionally active 20 kDa protein was sequenced from blots, and the N-terminal sequence obtained was found to be DEP(A)TDAAT(R)NND. A novel strategy, based on the single-specific-primer polymerase chain reaction technique, enabled the gene inactivated by Tn916 to be cloned. Analysis of the resultant nucleotide sequence revealed an open reading frame of 585 bp, designated amylase-binding protein A (abpA), encoding a protein of 20 kDa (AbpA), immediately downstream from the insertion site of Tn916. This protein possessed a potential signal peptide followed by a region having identity with the N-terminal sequence of the 20 kDa amylase-binding protein. These results demonstrate the role of the 20 kDa protein in the binding of amylase to S. gordonii. Knowledge of the nature of amylase-binding proteins may provide a better understanding of the role of these proteins in the colonization of S. gordonii in the oral cavity. [References: 49] <12> UI - 1998103245 AU - Genco RJ IN - Dr. R.J. Genco, Department of Oral Biology, School of Dental Medicine, Faculty of Health Sciences, Buffalo, NY 14214; United States. TI - Periodontal disease and risk for myocardial infarction and cardiovascular disease. SO - Cardiovascular Reviews & Reports Vol 19(3) (pp 34-40), 1998. AB - There are several known risk factors for myocardial infarction and cardiovascular disease, such as smoking, hypertension, obesity, diabetes, and high cholesterol. However, there remains significant risk for cardiovascular disease that is yet unexplained. Several case control and epidemiologic studies have found a strong association between periodontal disease and cardiovascular disease, suggesting that periodontal infection is also a risk factor for cardiovascular disease. Specific bacteria have been found in the oral cavity, as well as the blood stream, of patients with periodontal disease, and these bacteria have been shown to induce platelet activation and aggregation. Oral bacteria may have a direct or indirect effect on the heart, and there are several proposed mechanisms by which the presence of periodontal disease may trigger certain events, leading to thrombotic events and myocardial infarction. Studies are under way to investigate these mechanisms to further explain the association between periodontal disease and cardiovascular disease. [References: 17] <13> UI - 1997372697 AU - Love RM AU - McMillan MD AU - Jenkinson HF IN - H.F. Jenkinson, Dept. of Oral and Dental Science, University of Bristol, Dental Hospital and School, Lower Maudlin St., Bristol BS1 2LY; United Kingdom. TI - Invasion of dentinal tubules by oral streptococci is associated with collagen recognition mediated by the antigen I/II family of polypeptides. SO - Infection & Immunity Vol 65(12) (pp 5157-5164), 1997. AB - Cell surface proteins SspA and SspB in Streptococcus gordonii and SpaP in Streptococcus mutans are members of the antigen I/II family of polypeptides produced by oral streptococci. These proteins are adhesins and mediate species-specific binding of cells to a variety of host and bacterial receptors. Here we show that antigen I/II polypeptides are involved in the attachment of oral streptococci to collagen and that they also determine the ability of these bacteria to invade human root dentinal tubules. Wild-type S. gordonii DL1 (Challis) cells showed heavy invasion of tubules to a depth of approximately 200 mum, whereas the abilities of cells of isogenic mutant strains OB220 (sspA) and OB219 (sspA sspB) to invade were 50 and >90% reduced, respectively. Likewise, wild-type S. mutans NG8 cells invaded dentinal tubules, whereas cells of isogenic mutant strain 834 (spaP) did not. The invasive abilities of strains OB220 and OB219 were restored by heterologous expression of S. mutans SpaP polypeptide in these strains. The extents of tubule invasion by various wild-type and mutant strains correlated with their levels of adhesion to type I collagen, a major component of dentin. Furthermore, S. gordonii DL1 cells exhibited a growth response to collagen by forming long chains. This was not shown by ssp mutants but was restored by the expression of SpaP in these cells. The production of SspA polypeptide by S. gordonii DL1, but not production of SspB polypeptide by strain OB220 (sspA), was enhanced in the presence of collagen. These results are the first to demonstrate that antigen I/II family polypeptides bind collagen and mediate a morphological growth response of streptococci to collagen. These antigen I/II polypeptide activities are critical for intratubular growth of streptococci and thus for establishment of endodontic infections. [References: 49] <14> UI - 1997372697 AU - Love RM AU - McMillan MD AU - Jenkinson HF IN - H.F. Jenkinson, Dept. of Oral and Dental Science, University of Bristol, Dental Hospital and School, Lower Maudlin St., Bristol BS1 2LY; United Kingdom. TI - Invasion of dentinal tubules by oral streptococci is associated with collagen recognition mediated by the antigen I/II family of polypeptides. SO - Infection & Immunity Vol 65(12) (pp 5157-5164), 1997. AB - Cell surface proteins SspA and SspB in Streptococcus gordonii and SpaP in Streptococcus mutans are members of the antigen I/II family of polypeptides produced by oral streptococci. These proteins are adhesins and mediate species-specific binding of cells to a variety of host and bacterial receptors. Here we show that antigen I/II polypeptides are involved in the attachment of oral streptococci to collagen and that they also determine the ability of these bacteria to invade human root dentinal tubules. Wild-type S. gordonii DL1 (Challis) cells showed heavy invasion of tubules to a depth of approximately 200 mum, whereas the abilities of cells of isogenic mutant strains OB220 (sspA) and OB219 (sspA sspB) to invade were 50 and >90% reduced, respectively. Likewise, wild-type S. mutans NG8 cells invaded dentinal tubules, whereas cells of isogenic mutant strain 834 (spaP) did not. The invasive abilities of strains OB220 and OB219 were restored by heterologous expression of S. mutans SpaP polypeptide in these strains. The extents of tubule invasion by various wild-type and mutant strains correlated with their levels of adhesion to type I collagen, a major component of dentin. Furthermore, S. gordonii DL1 cells exhibited a growth response to collagen by forming long chains. This was not shown by ssp mutants but was restored by the expression of SpaP in these cells. The production of SspA polypeptide by S. gordonii DL1, but not production of SspB polypeptide by strain OB220 (sspA), was enhanced in the presence of collagen. These results are the first to demonstrate that antigen I/II family polypeptides bind collagen and mediate a morphological growth response of streptococci to collagen. These antigen I/II polypeptide activities are critical for intratubular growth of streptococci and thus for establishment of endodontic infections. [References: 49] <15> UI - 1997350092 AU - Tsuchida M AU - Mineshita S AU - Okonogi H AU - Sugimori K AU - Hoshi K AU - Horiuchi T AU - Wang L-M AU - Fujimoto EK IN - M. Tsuchida, Major in Health Science, Faculty of Human Sciences, Aichi Mizuho College, 86-1, Haiwa, Hiratobashi-cho, Toyota 470-03; Japan. TI - The role of an uncommon type of oral streptococcus sanguis in the etiology of Behcet's disease. SO - Environmental Health & Preventive Medicine Vol 2(2) (pp 59-63), 1997. AB - The relationships of Behcet's disease (BD) with oral diseases and the prevalence of an uncommon type of oral Streptococcus sanguis (Str. sanguis) in the oral cavity were investigated in a case-control study. BD patients were compared to patient controls (collagen disease) and healthy controls. An interview questionnaire survey of BD and oral diseases showed that during the pre-onset, onset, and post-onset periods, the incidences of tonsillitis and dental caries, or the history of dental treatment, were greater in BD cases. Typological analysis showed a higher prevalence of an uncommon type of Str. sanguis, differing from the common type, among BD cases compared to control groups. These results, showing a higher incidence of tonsillitis and dental caries during the presymptomatic period, a greater frequency of dental treatments during the symptomatic period, and the presence of an uncommon type of Str. sanguis, indicate that Str. sanguis of an uncommon type is related to increased risk of BD, and the possibility of a causal role is suggested. [References: 32] <16> UI - 1997334132 AU - Lucas VS AU - Beighton D AU - Roberts GJ AU - Challacombe SJ IN - V.S. Lucas, The Great Ormond St. Hosp. Children, Maxillofacial and Dental Department, London WC1N 1JH; United Kingdom. TI - Changes in the oral streptococcal flora of children undergoing allogeneic bone marrow transplantation. SO - Journal of Infection Vol 35(2) (pp 135-141), 1997. AB - The changes in the oral streptococcal flora of twenty children undergoing allogeneic bone marrow transplant are described. Saliva was collected from each child on four separate occasions: (i) before the conditioning regimen; (ii) 7 days post-transplantation; (iii) when the neutrophil count had risen above 0.5 x 109/l; (iv) 119 days post-transplantation. Indices for dental caries, plaque, gingivitis, herpetic stomatitis and mucositis were also recorded. There was a significant decrease in the total aerobic (P < 0.001 and anaerobic counts (P < 0.0002) between baseline and 7 days post-transplantation. The proportion of the 'Streptococcus oralis group' (Streptococcus mitis and S. oralis) increased significantly from baseline 12.1% to 48.4% at 7 days post-transplantation (P < 0.003). The plaque and gingivitis indices increased significantly from baseline to 7 days post-transplantation (P < 0.001). Twenty percent of the children had either positive blood cultures or Hickman line cultures for the 'S. oralis group', and it is possible that the inflamed gingival tissues are a further site of entry for these streptococci. There were no differences in the total anaerobic counts or the proportion of the 'S. oralis group' between baseline and the end of the study in the transplant children, or between the transplant and control children. [References: 30] <17> UI - 1997282748 AU - Maiden MFJ AU - Macuch PJ AU - Murray L AU - Tanner A IN - Dr. M.F.J. Maiden, Dept. of Periodontal Microbiology, Forsyth Dental Center, 140 Fenway, Boston, MA 02115; United States. TI - 'Checkerboard' DNA-probe analysis and anaerobic culture of initial periodontal lesions. SO - Clinical Infectious Diseases Vol 25(SUPPL. 2) (pp S230-S232), 1997. <18> UI - 1996203932 AU - Johansson A AU - Bergenholtz A AU - Holm SE IN - Department of Periodontology, Umea University,S-902 85 Umea; Sweden. TI - The interference of gingival cell cultures with growth of selected bacteria. SO - APMIS Vol 104(5) (pp 367-373), 1996. AB - The aim of the present study was to analyze the interference of oral tissue cells or cell lines (effector cells) with growth of reference bacteria, and furthermore to investigate whether cells derived from different individuals differ in such activity. The reference bacteria were Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mitis, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Fusobacterium nucleatum. The effector cells used were gingival fibroblasts (GF) from 21 periodontally involved persons, gingival epithelial cells (E) from 2 such persons, HeLa cells (HeLa), and an amnion cell line (Amnion). The cells were cultivated and their supernatants tested for antibac terial activity in a Bioscreen robot analyzer (Labsystems, Finland). Results suggest that the antibac terial activity of each tested primary cell line of tissue had its own profile depending on cell type and donor, and that the composition of oral microbiota was influenced by oral cells, which might, in turn, contribute to the variations in the pathogenesis of periodontal diseases. <19> UI - 1996134725 AU - Levine M AU - Miller FC IN - Biochemistry/Molecular Biology Dept., Oklahoma Univ. Health Sciences Ctr., 940 Stanton L. Young Blvd.,Oklahoma City, OK 73104; United States. TI - An Eikenella corrodens toxin detected by plaque toxin-neutralizing monoclonal antibodies. SO - Infection & Immunity Vol 64(5) (pp 1672-1678), 1996. AB - Bacterial plaque from the gingival region of teeth contains cytotoxic agents which lyse undifferentiated human HL60 cells. A small panel of monoclonal antibodies (MAbs) was found to abrogate much of this activity and to detect antigens in certain strains of Streptococcus mitis and Eikenella corrodens. The aim of this study was to determine whether these bacterial antigens might be involved in HL60 cell cytolysis. Saline extracts were obtained by homogenizing washed, stationary-phase cells in 65 mM NaCl with a tight-fitting Potter. Elvehjem homogenizer. The extracts of E. corrodens were toxic to HL60 cells, whereas similar extracts of S. mitts were nontoxic. Adding plaque toxin-neutralizing MAb 3hE5 blocked the toxic effect of E. corrodens extract. S. mitts extracts contained a single, strongly reactive antigen of 140 kDa (s140K antigen) detected on Western blots (immunoblots) by three MAbs from the panel. Rabbit antibodies raised to this antigen excised from the gel (anti-s140K serum) detected larger antigens in addition to s140K. E. corrodens extracts contained a number of antigens detected by the MAbs. Immunoglobulin G (IgG) was purified from anti-s140K serum by passage through DE52 cellulose. A 100-fold excess (by weight) of the purified IgG to E. corrodens protein specifically cross-precipitated an 80-kDa antigen plus a nonantigenic 16-kDa protein, presumably attached noncovalently. The remaining supernatant fraction had no toxic activity. A similar ratio of control IgG (from nonimmunized rabbits) did not precipitate these proteins, and the supernatant fraction had the same activity as the extract not treated with IgG. The proteins of 80 and 16 kDa were also detected in the anti-s140K immunoprecipitate by rabbit IgG antibodies to E. corrodens whole cells. The 80-kDa antigen, alone or complexed with the 16-kDa protein, may be involved in mediating the toxic activity in E. corrodens and plaque extracts. <20> UI - 1996116330 AU - Soukos NS AU - Wilson M AU - Burns T AU - Speight PM IN - Department of Oral Pathology, Eastman Dental Institute, 256 Gray's Inn Road,London WC1X 8LD; United Kingdom. TI - Photodynamic effects of toluidine blue on human oral keratinocytes and fibroblasts and Streptococcus sanguis evaluated in vitro. SO - Lasers in Surgery & Medicine Vol 18(3) (pp 253-259), 1996. AB - Background and Objective: Some oral bacteria are susceptible to killing by red light after their sensitization with toluidine blue O (TBO). The photochemotherapy of periodontal disease in vivo would require a therapeutic window where bacteria could be killed without adjacent normal tissue damage. Study Design/Materials and Methods: The laser-induced effects of TBO on normal human gingival keratinocytes and fibroblasts have been studied in vitro. For the assessment of viability, the CellTiter 96(TM) AQueous Non- Radioactive Cell Proliferation Assay was used. Results: TBO was cytotoxic at low concentrations (5.0 mug/ml). Sensitization of keratinocytes and fibroblasts with 2 and 5.0 mug/ml TBO, respectively, for 5 min and exposure to light from a 7.3 mW Helium/Neon (HeNe) laser for up to 2 min (0.876J) did not reduce cell viability. However, killing of Streptococcus sanguis was achieved following exposure to HeNe light for 75 sec (0.547J) in the presence of TBO at a concentration of 2.5 mug/ml. Conclusion: The development of a system for the lethal photosensitization of bacteria responsible for periodontal disease may be possible. <21> UI - 1996053076 AU - Bloomquist CG AU - Reilly BE AU - Liljemark WF IN - Department of Diagnostic, School of Dentistry, University of Minnesota,Minneapolis, MN 55455; United States. TI - Adherence, accumulation, and cell division of a natural adherent bacterial population. SO - Journal of Bacteriology Vol 178(4) (pp 1172-1177), 1996. AB - Developing denial bacterial plaques formed in vivo on enamel surfaces were examined in specimens from 18 adult volunteers during the first day of plaque formation. An intraoral model placing enamel pieces onto teeth was used to study bacterial plaque populations developing naturally to various cell densities per square millimeter of surface area of the enamel (W. F. Liljemark, C. G. Bloomquist, C. L. Bandt, B. L. Philstrom, J. E. Hinrichs, and L. F. Wolff, Oral Microbiol. Immunol. 8:5-15, 1993). Radiolabeled nucleoside incorporation was used to measure DNA synthesis concurrent with the taking of standard viable cell counts of the plaque samples. Results showed that in vivo plaque formation began with the rapid adherence of bacteria until ca. 12 to 32% of the enamel's salivary pellicle was saturated (ca. 2.5 x 105 to 6.3 x 105 cells per mm2). The pioneer adherent species were predominantly those of the 'sanguis streptococci.' At the above-noted density, the bacteria present on the salivary pellicle incorporated low levels of radiolabeled nucleoside per viable cell. As bacterial numbers reached densities between 8.0 x 105 and 2.0 x 106 cells per mm2, there was a small increase in the incorporation of radiolabeled nucleosides per cell. At 2.5 x 106 to 4.0 x 106 cells per mm2 of enamel surface, there was a marked increase in the incorporation of radiolabeled nucleosides per cell which appeared to be cell-density dependent. The predominant species group in developing denial plaque films during density-dependent growth was the sanguis streptococci; however, most other species present showed similar patterns of increased DNA synthesis as the density noted above approached 2.5 x 106 to 4.0 x 106 cells per mm2. <22> UI - 1995061076 AU - Lacroix J-M AU - Walker CB IN - Ct. Infection/Biomaterials Research, Toronto Hospital, 200 Elizabeth Street,Toronto, Ont. M5G 2C4; Canada. TI - Detection and incidence of the tetracycline resistance determinant tet(M) in the microflora associated with adult periodontitis. SO - Journal of Periodontology Vol 66(2) (pp 102-108), 1995. AB - Subgingival plaque samples were collected from 68 patients with adult periodontitis, enumerated on Trypticase-soy blood agar plates, with and without tetracycline at 4 mug/ml, and incubated anaerobically for 5 days. Each different colony morphotype was enumerated, and a representative colony was subcultured for identification and examined for the tetracycline resistance gene tet(M). Both PCR amplification and DNA hybridization, using a fragment of tet(M) from Tn1545, were used to detect tet(M). The PCR primers (5'-GACACGCCAGGACATATGG-3' and 5'-TGCTTTCCTCTTGTTCGAG-3') were chosen to amplify a 397 bp region of tet(M). Tetracycline-resistant bacteria represented approximately 12% of the total viable count. The percentage of tet(M)-positive bacteria in the tetracycline resistant microflora varied from <=0.05 to 83% (mean of 10%). tet(M) was detected in 60% of 204 tetracycline-resistant strains subcultured and identified. The tet(M) containing strains consisted of streptococci (55%, mainly S. intermedius, S. oralis, S. sanguis, and Streptococcus SM4), Actinomyces D01 (14%), Bifidobacterium D05 (11%), and Veillonella spp. (10%). Tetracycline-resistant strains in which tet(M) was not detected included the Prevotella and Bacteroides species (41%, mainly Bacteroides D28, P. intermedia, P. nigrescens, and P. oris). These results suggest that tet(M) is widely spread in the adult periodontal microflora, but it appears, with the exception of S. intermedius, to be mainly associated with microorganisms not considered to be periodontopathogens. Assessment of other tetracycline-resistant genes in oral organisms is needed to fully evaluate the nature of resistance to this antibiotic in the oral flora. <23> UI - 1994375324 AU - Kampe CE AU - Vovan T AU - Alim A AU - Berenson J IN - UCLA Center for the Health Sciences, 11-260 Factor Bldg.,Los Angeles, CA 90024; United States. TI - Streptococcus sanguis bacteremia and colorectal cancer: A case report. SO - Medical & Pediatric Oncology Vol 24(1) (pp 67-68), 1995. AB - Streptococcus sanguis, usually considered a nonpathogen of the oral cavity, was isolated from blood cultures from a patient who was subsequently found to have a cecal adenocarcinoma. Further studies are needed to determine if Streptococcus sanguis infections have diagnostic implications similar to those of Streptococcus bovis. <24> UI - 1994263244 AU - Bartzokas CA AU - Johnson R AU - Jane M AU - Martin MV AU - Pearce PK AU - Saw Y IN - Department of Medical Microbiology, Wirral Hospital NHS Trust, Clatterbridge Hospital,Bebington, Wirral L63 4JY; United Kingdom. TI - Relation between mouth and haematogenous infection in total joint replacements. SO - British Medical Journal Vol 309(6953) (pp 506-508), 1994. AB - Objective - To investigate the source of infections associated with orthopaedic prostheses. Design - Analysis of four infections of prosthetic joints with case records; minimum inhibitory and minimum bactericidal concentrations and sodium dodecylsulphate polyacrylamide gel electrophoresis of the cell wall polypeptides of the Streptococcus sanguis isolates from the mouth and infected prostheses; examination of the patients' mouths for periodontal disease and caries. Subjects - Four adults (three men) aged 58-83. Results - For each patient the strain of S sanguis isolated from the mouth was indistinguishable from that isolated from the prosthesis. All patients had severe periodontal disease and caries. Conclusions - The mouth was probably the source of bacterial infection in the prosthetic joints of these patients; the route of infection was possibly haematogenous. Incipient oral infection should be treated before joint replacement, and oral health should be maintained indefinitely. <25> UI - 1994120796 AU - Piotrowski J AU - Murty VLN AU - Czajkowski A AU - Slomiany A AU - Yotsumoto F AU - Majka J AU - Slomiany BL IN - Research Center, Univ of Med and Dent of New Jersey,Newark, NJ 07103-2400; United States. TI - Association of salivary bacterial aggregating activity with sulfomucin. SO - Biochemistry & Molecular Biology International Vol 32(4) (pp 713-721), 1994. AB - The requirements of human salivary mucins for aggregating potential towards the common cariogenic oral bacteria, S. mutans and S. sanguis, were investigated. Agglutination inhibition assays demonstrated that the aggregating capacity towards bacteria resides in the acidic mucin fraction. The inhibitory activity of the acidic mucin decreased only 2-4-fold following removal of sialic acid, whereas the desulfation caused a complete loss of the inhibitory potential against both bacteria. Furthermore, the aggregating capacity of mucin-derived sulfated oligosaccharide was found to be 16-fold higher than that of the sialic acid containing oligosaccharide. The results point towards the importance of salivary sulfomucins as a predominant factor in the defense of oral cavity against cariogenic bacteria. <26> UI - 1994045628 AU - Mattila KJ IN - Department of Medicine, Helsinki University Central Hospital, Haartmaninkatu 4,00290 Helsinki; Finland. TI - Dental infections as a risk factor for acute myocardial infarction. SO - European Heart Journal Vol 14(SUPPL. K) (pp 51-53), 1993. AB - The so-called classic risk factors of coronary heart disease (CHD) do not explain all its clinical and epidemiological features. Recent evidence suggests that certain infections, among them dental infections, are involved in the pathogenesis of CHD. Case-control studies have revealed an association between dental infections and acute myocardial infarction and chronic coronary heart disease. A large epidemiological survey revealed an association between missing teeth and CHD and a recent 14-year follow-up of 9760 individuals showed that periodontitis is associated with an increased risk of coronary heart disease. Preliminary results suggest that the severity of dental infections correlates with the extent of coronary atheromatosis. Individuals with severe dental infections also have higher level of von Willebrand factor antigen, leukocytes and fibrinogen Streptococcus sanguis has been shown to aggregate human platelets in vitro. The mechanism behind the association between dental infections and CHD could be the effect of bacteria on the cells taking part in the pathogenesis of atherosclerosis and arterial thrombosis. <27> UI - 1994012822 AU - Moisset A AU - Schatz N AU - Lepoivre Y AU - Amadio S AU - Wachsmann D AU - Scholler M AU - Klein J-P IN - Faculte de Pharmacie, Unite INSERM, Batiment D, 74, Route du Rhin,67401 Illkirch Cedex; France. TI - Conservation of salivary glycoprotein-interacting and human immunoglobulin G-cross-reactive domains of antigen I/II in oral streptococci. SO - Infection & Immunity Vol 62(1) (pp 184-193), 1994. AB - In this study we localized more precisely the salivary glycoprotein- interacting and the human immunoglobulin G (hIgG)-cross-reacting domains on the SR molecule, an antigen I/II-related protein from S. mutans serotype f. Mapping of the SR molecule with polypeptides expressed by subclones covering the entire molecule and with synthetic peptides demonstrates that the salivary glycoprotein-binding domain is located in the N-terminal alanine- rich repeats of the SR molecule. In order to investigate the degree of conservation of both regions in various oral streptococci, we tested the reactivity of 8 representative strains of the mutans group and 11 nonmutans oral Streptococcus strains (S. anginosus, S. milleri, S. constellatus, S. intermedius, S. mitis, S. sanguis, S. gordonii, S. salivarius, and S. mitis strains) with antipeptide antibodies in a whole-cell enzyme linked immunosorbent assay together with colony hybridization analysis using DNA probes designed to map these two regions. All the mutans group strains except S. rattus and the 11 nonmutans streptococcal strains showed a high conservation of the C-terminal part of the SR molecule, especially the hIgG- cross-reacting domain, and less homology for the N-terminal salivary glycoprotein-binding region. Almost all of the sera from patients with rheumatic disease reacted strongly with SR from S. mutans serotype f, P1 from S. mutans serotype c, and four peptides located in the hIgG-cross-reacting region and not with peptides located at the C and N termini and in the proline-rich repeats. These results confirm that epitopes located within this region are immunogenic in humans and could lead to the synthesis of natural anti-IgG antibodies. <28> UI - 1993260094 AU - Reinholdt J AU - Friman V AU - Kilian M IN - Department of Oral Biology, Faculty of Health Sciences, University of Aarhus,DK-8000 Aarhus C; Denmark. TI - Similar proportions of immunoglobulin A1 (IgA1) protease-producing streptococci in initial dental plaque of selectively IgA-deficient and normal individuals. SO - Infection & Immunity Vol 61(9) (pp 3998-4000), 1993. AB - By comparing the initial colonization of cleaned teeth in immunoglobulin A (IgA)-deficient, IgM-compensating individuals with that in normal individuals, no significant difference in the proportion of IgA1 protease- producing streptococci was found. Thus, as one of several bacterial means of immune evasion, the ability to cleave secretory IgA1 does not appear essential to the successful adherence of oral streptococci. <29> UI - 1993260040 AU - Hocini H AU - Iscaki S AU - Bouvet J-P AU - Pillot J IN - Service Microbiologie/d'Immunologie, Hopital A. Beclere,92141 Clamart; France. TI - Unexpectedly high levels of some presumably protective secretory immunoglobulin A antibodies to dental plaque bacteria in salivas of both caries-resistant and caries-susceptible subjects. SO - Infection & Immunity Vol 61(9) (pp 3597-3604), 1993. AB - The role of salivary antibodies in protection against cariogenic bacteria is actually a matter of debate. Correlation between caries experience and naturally occurring antibodies was extensively investigated. Comparison of salivary antibodies from 21 caries-resistant and 22 caries-susceptible subjects was carried out by using a new quantitative method. Secretory immunoglobulin A (S-IgA) antibodies to Streptococcus sobrinus and Streptococcus sanguis cells were detected in all salivas and at similar levels in both groups. When assayed with two major antigens from S. sobrinus, i.e., protein antigen I/II and cell wall carbohydrates, only specific activities of antibodies to the protein component were increased (P < 0.001), but this occurred unexpectedly in the caries-susceptible group. Western blot (immunoblot) analysis with the culture supernatant and cell wall proteins from S. sobrinus showed the same antibody specificity in both groups. No selective increase of the protease-resistant S-IgA2 subclass was found, and avidities of antibodies to both antigen I/II and cell wall carbohydrates were similar. Our results demonstrate that naturally induced S-IgA antibodies against S. sanguis, S. sobrinus, and the major antigens of the latter are not sufficient to inhibit caries development. <30> UI - 1993168623 AU - Slomiany BL AU - Piotrowski J AU - Czajkowski A AU - Shovlin FE AU - Slomiany A IN - Research Center, New Jersey Dental School, Univ. Med./Dentistry of New Jersey, 110 Bergen Street,Newark, NJ 07103-2400; United States. TI - Differential expression of salivary mucin bacterial aggregating activity with caries status. SO - International Journal of Biochemistry Vol 25(6) (pp 935-940), 1993. AB - The low and high mol. wt mucin forms were isolated from saliva of caries-resistant (CR) and caries-susceptible (CS) individuals, and assessed for their bacterial aggregating potential towards S. mutans and S. sanguis, the common cariogenic microorganisms encountered in the oral cavity. The high mol. wt mucin from both groups of subjects exhibited similar protein and carbohydrate content, but the level of covalently bound fatty acids was significantly lower in the CR group. The mucin from CR group showed only a weak inhibitory potential, and no inhibitory activity was observed with the mucin of CS group. The low mol. wt mucins from both groups, while displaying compositional similarities, showed a marked variation in the bacterial aggregating activity. With both bacteria, the activity of the mucin from CR group was at least 128-fold greater than that of CS group. The conversion of the high mol. wt mucin to a low mol. wt form through the action of salivary protease produced in both groups enhancement in mucin's bacterial aggregating capacity. This enhancement was, however, considerably less pronounced in the case of mucin from CS group. The results for the first time demonstrate that the bacterial aggregating epitope of salivary mucins is expressed to a greater extent in CR individuals, and that this epitope is apparently more accessible to bacteria in the low mol. wt mucin form. <31> UI - 1993167075 AU - Gossel TA IN - Department of Clinical Pharmacy, Ohio Northern University,Ada, OH; United States. TI - Combatting plaque with mouthrinses. SO - U.S. Pharmacist Vol 17(12) (pp 27-32), 1992. <32> UI - 1993068522 AU - Piotrowski J AU - Czajkowski A AU - Slomiany A AU - Shovlin FE AU - Murty VLN AU - Slomiany BL IN - Research Center, New Jersey Dental School, University of Medicine and Dentistry,Newark, NJ 07103-2400; United States. TI - Expression of salivary mucin bacterial aggregating activity: Difference with caries. SO - Biochemistry International Vol 28(6) (pp 1021-1028), 1992. AB - The low and high molecular weight mucin forms were isolated from saliva of individuals with different caries status and assessed for their bacterial aggregating potential towards S. mutans and S. sanguis. The high molecular weight mucin from both groups exhibited similar protein and carbohydrate content, but the level of covalently bound fatty acids was lower in the caries-resistant group. The mucin from caries-resistant group showed only a weak inhibitory potential, while no inhibitory activity was observed with the mucin of caries-susceptible group. The low molecular weight mucins from both groups, while displaying compositional similarities, showed a marked variation in the bacterial aggregating activity, and the titer of the mucin from caries-resistant group was at least 128-fold greater than that of caries-susceptible group. The results demonstrate that the bacterial aggregating epitop of salivary mucins is expressed to a greater extent in caries-resistant individuals, and that this epitop is apparently more accessible to bacteria in the low molecular weight mucin form. <33> UI - 1993057141 AU - Lewis MAO AU - Milligan SG AU - MacFarlane TW AU - Carmichael FA IN - Dept. of Oral Medicine/Pathology, University of Glasgow, Dental Hospital and School, 378 Sauchiehall Street,Glasgow G2 3JZ; United Kingdom. TI - Phagocytosis of bacterial strains isolated from acute dentoalveolar abscess. SO - Journal of Medical Microbiology Vol 38(2) (pp 151-154), 1993. AB - The phagocytosis by human polymorphonuclear leucocytes of 37 bacterial strains identified as Streptococcus milleri (10 strains), strictly anaerobic gram-positive cocci (10) Prevotella intermedia (6), Pr. oralis (5) and Fusobacterium nucleatum (6) was investigated in vitro. The ingestion of S. milleri and strictly anaerobic gram-positive cocci was significantly greater (p<0.001) than that of strains of Prevotella spp. and F. nucleatum. The degree of uptake of capsulate and non-capsulate strains did not differ. <34> UI - 1993042529 AU - Lehner T AU - Ma JK-C AU - Kelly CG IN - Department of Immunology, United Medical School of Guy's, St. Thomas' Hospitals,London; United Kingdom. TI - A mechanism of passive immunization with monoclonal antibodies to a 185,000 M(r) streptococcal antigen. SO - Advances in Experimental Medicine & Biology Vol 327 (pp 151-163), 1992. <35> UI - 1993042522 AU - Kilian M AU - Reinholdt J AU - Poulsen K AU - Lomholt H IN - Faculty of Health Sciences, Institute of Medical Microbiology, University of Aarhus,DK-8000 Aarhus C; Denmark. TI - IgAl proteases and host-parasite relationships in the oral cavity. SO - Advances in Experimental Medicine & Biology Vol 327 (pp 83-89), 1992. <36> UI - 1993006581 AU - Granath L AU - Cleaton-Jones P AU - Fatti LP AU - Grossman ES IN - Department of Pedodontics, School of Dentistry, Lund University,S-214 21 Malmo; Sweden. TI - Prevalence of dental caries in 4- to 5-year-old children partly explained by presence of salivary mutans streptococci. SO - Journal of Clinical Microbiology Vol 31(1) (pp 66-70), 1993. AB - The correlation between dental caries and the number of oral mutans group streptococci (ms) present has been shown to be weak. The aim of this investigation was to study associations between caries experience (decayed, missing, and filled surfaces [dmfs]) and the number of ms in stimulated saliva, with emphasis on the level of disease and the confounding effect of regular intake of sweets, the presence of salivary lactobacilli, and oral hygiene. In some 2,700 4- to 5-year-old South African children of different ethnic origins, caries was diagnosed on the basis of World Health Organization criteria and saliva samples were analyzed for ms after cultivation on mitis salivarius-bacitracin agar and for lactobacilli by using the Dentocult kit. Oral hygiene was scored on the basis of the Greene and Vermillion simplified debris index, while data on intake of sweets were derived from extensive interviews. Pearson's coefficient of correlation was computed, and multiple regression analysis was performed to correct for confounding factors. The distribution of the children in the eight caries classes was strongly associated with the ms class (P < 0.001), with those in the lower ms classes generally having low dmfs scores and those in the higher ms classes having dmfs scores distributed over the whole range. The r value for the two variables was 0.25 for the total material; this was reduced to 0.18 by correction for confounding factors. The corresponding values for children with caries were 0.21 and 0.17, for those in the 1 to 6 dmfs interval they were 0.07 and 0.03, and for those in the 7 to 81 dmfs interval they were 0.16 and 0.14. The data imply that the explanatory values of ms, those for the lower caries interval not counted, ranged from 6 to 2%. The unexpected results for children with caries might be due to their distribution pattern. It is concluded that there is a need for reevaluation of ms as a risk factor in dental caries. <37> UI - 1992219609 AU - Stinson MW AU - Haraszthy GG AU - Zhang XL AU - Levine MJ IN - Department of Microbiology, Sch. of Medicine/Biomedical Sciences, State University of New York,Buffalo, NY 14214; United States. TI - Inhibition of Porphyromonas gingivalis adhesion to Streptococcus gordonii by human submandibular-sublingual saliva. SO - Infection & Immunity Vol 60(7) (pp 2598-2604), 1992. AB - Porphyromonas gingivalis W50 adheres in vitro to biofilms of Streptococcus gordonii G9B. This phenomenon is believed to facilitate the initial colonization of the oral cavity by P. gingivalis and to contribute to the maturation of dental plaque. In this report, we describe the modulating effects of human submandibular-sublingual saliva (HSMSL) on this in vitro model of intergeneric bacterial adhesion (coaggregation). HSMSL inhibited P. gingivalis adhesion to S. gordonii by 50% at a concentration of 57 mug of protein per ml. Maximum inhibitory activity was associated with a 43-kDa protein obtained by sequential Sephadex G200 gel filtration and CM52 ion- exchange chromatography of HSMSL. Pools of other column fractions of HSMSL showed no effect or were slightly stimulatory for bacterial adhesion. The binding of radioiodinated column fractions containing the 43-kDa protein by P. gingivalis was accompanied by their rapid enzymatic degradation. Treating P. gingivalis at 60 [degree] C for 30 min or with protease inhibitors (phenylmethylsulfonyl fluoride and sodium iodoacetate) reduced adherence to streptococcal biofilms. These treatments did not prevent P. gingivalis from binding soluble HSMSL saliva components, although subsequent proteolysis was nearly eliminated. These observations indicate that surface-associated proteases of P. gingivalis, either independently or in concert with adjacent surface adhesins, interact with surfaces of oral streptococci to facilitate interbacterial adhesion. The adhesion-blocking properties of HSMSL, particularly the 43-kDa protein, may represent an important host defense mechanism in the oral cavity. <38> UI - 1991301741 AU - Lamont RJ AU - Demuth DR AU - Davis CA AU - Malamud D AU - Rosan B IN - Department of Oral Biology, School of Dentistry, University of Washington,Seattle, WA 98195; United States. TI - Salivary-agglutinin-mediated adherence of Streptococcus mutans to early plaque bacteria. SO - Infection & Immunity Vol 59(10) (pp 3446-3450), 1991. AB - Interspecies binding is important in the colonization of the oral cavity by bacteria. Streptococcus mutans can adhere to other plaque bacteria, such as Streptococcus sanguis and Actinomyces viscosus, and this adherence is enhanced by saliva. The salivary and bacterial molecules that mediate this interaction were investigated. Salivary agglutinin, a mucinlike glycoprotein known to mediate the aggregation of many oral streptococci in vitro, was found to mediate the adherence of S. mutans to S. sanguis or A. viscosus. Adherence of S. mutans to saliva- or agglutinin-coated S. sanguis and A. viscosus was inhibited by antibodies to the bacterial agglutinin receptor. Expression of the S. sanguis receptor (SSP-5) gene in Enterococcus faecalis increased adhesion of this organism to saliva- or agglutinin-coated S. sanguis and A. viscosus. This interaction could be inhibited by antibodies to the agglutinin receptor. The results suggest that salivary agglutinin can promote adherence of S. mutans to S. sanguis and A. viscosus through interactions with the agglutinin receptor on S. mutans. <39> UI - 1991148014 AU - Tzannetis SE AU - Bigis A AU - Konidaris N AU - Ioannidis H AU - Genimatas V AU - Papavassiliou J IN - Department of Microbiology, University of Athens, School of Medicine, Athens; Greece. TI - In-vitro bacteriocin-mediated antagonism by oral streptococci against human carrier strains of staphylococci. SO - Journal of Applied Bacteriology Vol 70(4) (pp 294-301), 1991. AB - All strains of oral streptococci tested and specially those of Streptococcus mutans, Strep. sanguis and Strep. mitior produced more than one distinct bacteriocin-like substance with variable inhibitory activity on 20 indicator staphylococci. Inhibitory activity was comparatively higher on nasal strains of Staph. aureus and Staph. epidermidis than on strains of both species isolated from the mouth. Nineteen of 20 staphylococcal indicators were inhibited by 1-12 of the 12 effector streptococci. Sensitivity of nasal staphylococci to bacteriocins (frequency of positive inhibitory tests and total inhibition zone diameters) was significantly higher (P<0.001, chi2 test and P<0.05, t test respectively) than that of oral ones. The sensitivity of nasal over oral Staph. aureus (P<0.001 and P<0.01) and of oral an Staph. epidermidis over oral Staph. aureus (P<0.01 and P<0.05) was also significantly higher. The evaluation of variability of inhibitory patterns of bacteriocins produced by streptococci (p-typing), of sensitivity patterns of staphylococci to bacteriocins (s-typing) and of the significantly higher sensitivity of nasal over oral staphylococci to bacteriocins from the epidemiological and ecological viewpoints are discussed. <40> UI - 1991063577 AU - Ahl T AU - Reinholdt J IN - Department of Oral Biology, Royal Dental College, Vennelyst Boulevard,DK-8000 Aarhus C; Denmark. TI - Detection of immunoglobulin A1 protease-induced Fab(alpha) fragments on dental plaque bacteria. SO - Infection & Immunity Vol 59(2) (pp 563-569), 1991. AB - The mechanisms by which immunoglobulin A1 (IgA1) protease activity may enable bacteria to evade the effect of specific secretory IgA (S-IgA) antibodies are not clear. A possibility which has received indirect experimental support is that bacteria, as a consequence of the protease activity, become coated with incompetent Fab(alpha) fragments instead of with intact antibody molecules. Using a combination of nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting, we detected Fab(alpha) fragments not only on oral streptococci (Streptococcus sanguis and Streptococcus gordonii) incubated in saliva but also on the bacteria in incipient dental plaque. These results are of relevance to our previous observation that IgA1 protease activity may neutralize the ability of S-IgA antibodies to inhibit the adherence of oral streptococci to saliva-coated hydroxyapatite. <41> UI - 1991058359 AU - Longman LP AU - Pearce PK AU - McGowan P AU - Hardy P AU - Martin MV IN - Department of Clinical Dental Sciences, School of Dentistry, University of Liverpool, PO Box 147, Liverpool L69 3BX; United Kingdom. TI - Antibiotic-resistant oral streptococci in dental patients susceptible to infective endocarditis. SO - Journal of Medical Microbiology Vol 34(1) (pp 33-37), 1991. AB - The aim of this study was to determine the incidence of amoxycillin and erythromycin resistance in oral streptococci in patients at risk from infective endocarditis. Samples of gingival crevicular flora were taken from 65 patients at the site of dental treatment, prior to the prophylactic administration of amoxycillin (54 patients) or erythromycin (11 patients). Samples were also taken from 65 dental patients who were not considered to be at risk from infective endocarditis. No isolate had a minimum inhibitory concentration (MIC) of amoxycyllin >24 mg/L. However, erythromycin-resistant oral streptococci with MIC values > 3.5 mg/L were isolated from 22% of patients receiving amoxycillin prophylaxis, 9% of patients receiving amoxycillin prophylaxis, 9% of patients given erythromycin prophylaxis and 9% of patients not at risk from infective endocarditis. The antibiotic-resistant streptococci comprised mainly Streptococcus sanguis biotype II, although S. sanguis biotype I, S. mitis and S. salivarius were also frequently recovered. <42> UI - 1990347569 AU - Fleming P AU - Freigal RJ AU - Kaplan EL AU - Liljemark WF AU - Little JW IN - School of Dentistry, Royal Victoria Hospital,Belfast BT12 6BP; United Kingdom. TI - The development of penicillin-resistant oral streptococci after repeated penicillin prophylaxis. SO - Oral Surgery, Oral Medicine, Oral Pathology Vol 70(4) (pp 440-444), 1990. AB - Oral streptococci may cause infective endocarditis in patients with susceptible cardiac disease after dental treatment. Multiple dental visits, each preceded by penicillin prophylaxis, may result in the unwanted development of resistant oral streptococci. This study was undertaken to determine whether resistant oral streptococci would develop after the repeated use of penicillin prophylaxis in healthy adults. Plaque samples were collected from 20 subjects on each Monday for 5 successive weeks. Each subject was administered 2 gm penicillin V followed by 1 gm 6 hours later (standard prophylaxis regimen of the American Heart Association), on three successive Mondays (weeks 2, 3, and 4). The total cultivable oral streptococci and penicillin-resistant oral streptococci were determined for each plaque sample, and representative colonies of resistant streptococci were speciated. During the study, there was a significant increase in the number of subjects who harbored penicillin-resistant oral streptococci. However, with the exception of one subject who had resistant streptococci throughout the study, the number of resistant strains represented only 0.0003% to 0.41% of the total cultivable oral streptococci. <43> UI - 1990299365 AU - Ma JK-C AU - Hunjan M AU - Smith R AU - Kelly C AU - Lehner T IN - Department of Immunology, United Medical Dental Schools, Guy's and St. Thomas's Hosp.,London SE1 9RT; United Kingdom. TI - An investigation into the mechanism of protection by local passive immunization with monoclonal antibodies against Streptococcus mutans. SO - Infection & Immunity Vol 58(10) (pp 3407-3414), 1990. AB - Local oral passive immunization with Streptococcus mutans-specific monoclonal antibody (MAb) (Guy's 13) prevented recolonization by indigenous S. mutans in human volunteers who had first been treated with a conventional antibacterial agent (chlorhexidine). The F(ab')2 fragment of the MAb was as protective as the intact immunoglobulin G, but the Fab fragment of the molecule failed to prevent recolonization of S. mutans. In subjects receiving the MAb Fab fragment, S. mutans levels in dental plaque and saliva reappeared at a similar rate to that found in sham-immunized subjects who received either saline or a nonprotective MAb. In vitro, MAb had no bacteriostatic or bacteriocidal effect on S. mutans. However, S. mutans grown in the presence of either intact immunoglobulin G MAb or the F(ab')2 fragment formed very long chains, which resulted in clumping of the cells. S. mutans grown with either saline or the MAb Fab fragment formed significantly shorter chains, more characteristic of streptococcal growth in liquid media. The results suggest that the two binding sites of the MAb molecule may be an essential feature for preventing streptococcal colonization but that the ability to bind to phagocytes and activate complement which resides in the Fc fragment is not essential. Protection against colonization by S. mutans lasting up to 2 years was observed in immunized subjects, although MAb was applied over a period of only 3 weeks. Furthermore, functional MAb was detected up to 3 days following application of MAb to the teeth. The long-term protection could not be accounted for by a persistence of MAb on the tooth surface, and we have suggested that it may be due to a shift in the balance of the oral flora which discouraged recolonization by S. mutans. However, examination of the proportions of Streptococcus sanguis and veillonella species in the recolonization experiments failed to reveal a significant change in the proportions of either organism, which returned to approximately the preexperimental levels in both the immunized and control groups. These findings confirm the in vivo functional specificity of the MAb to S. mutans but are not consistent with the suggestion that S. sanguis or veillonella take over the niche vacated by S. mutans, unless the shift in the proportion of these organisms cannot be detected by the method used. <44> UI - 1990176706 AU - Nyvad B AU - Kilian M IN - Department of Oral Anatomy,,, Dental Pathol./Operative Dent, Royal Dental College, Vennelyst Boulevard,DK-8000 Arhus C; Denmark. TI - Microflora associated with experimental root surface caries in humans. SO - Infection & Immunity Vol 58(6) (pp 1628-1633), 1990. AB - This study describes the microflora from actively progressing root surface caries lesions, in which mineral loss had been determined by quantitative microradiography. The caries lesions were produced experimentally in root surface specimens from human molars inserted in lower partial dentures carried for 3 months by six elderly individuals. A total of 780 bacterial isolates were identified from 13 plaque samples, collected with a punch technique, and six dentin samples. The composition of the microflora showed distinct individual differences. The microflora from plaque samples associated with the highest mineral loss was dominated by either Actinomyces viscosus or a combination of mutans streptococci (serotypes c, d, and f) and Lactobacillus species (L. casei and L. brevis). Plaque from root surfaces with less pronounced mineral loss harbored a more complex microflora comprising gram-positive rods, mutans streptococci, Streptococcus mitis biovar 1, Veillonella spp., gram-negative rods, and low numbers of lactobacilli. In the latter samples, individual variations in the proportions of mutans streptococci (serotypes c, d, and g), Actinomyces species (A. viscosus and A. naeslundii), and Veillonella parvula biotypes were observed. These findings suggest that certain species or combinations of species are more cariogenic than others and that dominance of single acidogenic species in particular is conducive to high caries activity. <45> UI - 1990152134 AU - Reinholdt J AU - Tomana M AU - Mortensen SB AU - Kilian M IN - Department of Oral Biology, Royal Dental College,DK-8000 Aarhus C; Denmark. TI - Molecular aspects of immunoglobulin A1 degradation by oral streptococci. SO - Infection & Immunity Vol 58(5) (pp 1186-1194), 1990. AB - Using a panel of 143 strains classified according to a novel taxonomic system for oral viridans-type streptococci, we reeaxamined the ability of oral streptococci to attack human immunoglobilun A1 (IgA1) molecules with IgA1 protease or glycosidases. IgA1 protease production was an exclusive property of all strains belonging to Streptococcus sanguis and Streptococcus oralis (previously S. mitior) and of some strains of Streptococcus mitis biovar 1. These are all dominant initiators of dental plaque formation. Degradation of the carbohydrates moiety of IgA1 molecules accompanied IgA1 protease activity in S. oralis and protease-producing strains of S. mitis biovar 1. Neuraminidase and beta-galactosidase were identified as extracellular enzymes in organisms of these taxa. By examination with enzyme-neutralizing antisera, four distinct IgA1 proteases were detected in S. sanguis biovars 1 to 3, S. sanguis biovar 4, S. oralis, and strains of S. mitis, respectively. The cleavage of IgA1 molecules by streptococcal IgA proteases was found to be influenced by their state of glycosylation. Treatment of IgA1 with bacterial (including streptococcal) neuraminidase increased susceptibility to protease, suggesting a cooperative activity of streptococcal IgA1 protease and neuraminidase. In contrast, a decrease in susceptibility was observed after extensive deglycosylation of the hinge region with endo-alpha-N acetylgalactosaminidase. The effector functions of IgA antibodies depend on the carbohydrate-containing Fc portion. Hence, the observation that oral streptococci may cleave not only the alpha1 chains but also the carbohydrate moiety of IgA1 molecules suggests that the ability to evade secretory immune mechanisms may contribute to the successful establishment of these bacteria in the oral cavity. <46> UI - 1990139573 AU - Iwu C AU - MacFarlane TW AU - MacKenzie D AU - Stenhouse D IN - Oral Microbiology Unit, Dental Hospital and School, 378 Sauchiehall St.,Glasgow G2 3JZ; United Kingdom. TI - The microbiology of periapical granulomas. SO - Oral Surgery, Oral Medicine, Oral Pathology Vol 69(4) (pp 502-505), 1990. AB - Of the 16 periapical granulomas studied, 14 (88%) yielded a positive growth when homogenized and cultured. The concentration of colony-forming units per milliliter of the suspension ranged from 101.3 to 104.0 (mean 102.2). A total of 47 isolates comprising 26 (55%) facultative anaerobes and 21 (45%) strict anaerobes were obtained. The organisms most commonly cultured were Veillonella species (15%), Streptococcus milleri (11%), Streptococcus sanguis (11%), Actinomyces naeslundii (11%), Propionibacterium acnes (11%), and Bacteroides species (10%). Most of the organisms (96%) were sensitive to either amoxicillin, clindamycin, or tetracycline, whereas only 45% were sensitive to metronidazole. <47> UI - 1990083089 AU - Marquis RE IN - Department of Microbiology, University of Rochester, Rochester, NY 14642; United States. TI - Physiology of fluoride inhibition of oral bacteria. SO - Journal of Dental Research Vol 68(SPEC. ISS. NOV.) (pp 1694-1695), 1989. <48> UI - 1989212940 AU - Berga S AU - Trierweiler MW IN - Department of Obstetrics and Gynecology, Saint Joseph Hospital, Denver, CO 80218; United States. TI - Bacterial meningitis following epidural anesthesia for vaginal delivery: A case report. SO - Obstetrics & Gynecology Vol 74(3 II SUPPL.) (pp 437-439), 1989. AB - Acute bacterial meningitis following epidural anesthesia is a rare event. We describe a case in which a young woman received epidural anesthesia for vaginal delivery. The initial attempt at placement of the epidural resulted in entry into the subarachnoid space. The patient's postpartum course was complicated by persistent headache. She received epidural blood patch on two occasions, but her headache continued and she developed persistent fever. The diagnosis of acute bacterial meningitis was made on postpartum day 3. Contamination of the subarachnoid space may have occurred at the time of the inadvertent spinal tap or via the epidural blood patch. Alternatively, this contamination may have occurred during a spontaneous bacteremic episode, as Streptococcus sanguis is a mouth organism commonly involved in dental caries. <49> UI - 1989132974 AU - Giertsen E AU - Scheie AM AU - Rolla G IN - Department of Pedodontics and Caries Prophylaxis, Dental Faculty, University of Oslo, N-0455 Oslo 4; Norway. TI - Antimicrobial and antiplaque effects of a chlorhexidine and Triton X-100 combination. SO - Scandinavian Journal of Dental Research Vol 97(3) (pp 233-241), 1989. <50> UI - 1989120833 AU - Kilian M AU - Reinholdt J AU - Nyvad B AU - Frandsen EVG AU - Mikkelsen L IN - The Royal Dental College, DK-8000 Arhus C; Denmark. TI - IgA1 proteases of oral streptococci: Ecological aspects. SO - Immunological Investigations Vol 18(1-4) (pp 161-170), 1989. AB - The ecology and identity of IgA1 protease-producing streptococci in the human oral cavity were studied in an attempt to obtain insight into the significance of IgA1 proteases for host-parasite relationships. Contrary to previous observations, a detailed taxonomic analysis of oral streptococci revealed that all strains of S. sanguis and S. oralis ('S. mitior') produced IgA1 protease. In addition, IgA1 protease activity was observed in some isolates of S. mitis. Of the streptococci that initiate plaque formation on dental enamel 88% (median value) had IgA1 protease activity. Low proportions of the streptococci that colonize the tongue and oropharyngeal mucosae produced IgA1 protease, in contrast to 60% of streptococci isolated from buccal mucosa. The IgA1 proteases from S. sanguis I-III, S. sanguis IV, S. oralis, and S. mitis were distinct as revealed by studies using enzyme-neutralizing antibodies. <51> UI - 1988053046 AU - Jones CL AU - Stephen KW AU - Ritchie JA AU - Huntington E AU - Saxton CA AU - Van Der Ouderaa FJG IN - Gibbs Dental Division, Unilever Research, Port Sunlight Laboratory, Wirral, Merseyside L63 3JW; United Kingdom. TI - Long-term exposure of plaque to zinc citrate. SO - Caries Research Vol 22(2) (pp 84-90), 1988.