Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| acquisition of manganous ions by mutans group streptococci. | the cariogenic bacteria streptococcus sobrinus and s. cricetus were shown to have an absolute requirement for manganous ion in order to bind glucans or to adhere to glass in the presence of sucrose. the bacteria possessed a reasonably high affinity transport system for 54mn2+, yielding a km of about 12 microm. the vmax for uptake of 54mn2+ in s. sobrinus was increased when the bacteria were grown in mn-depleted medium, but the km remained the same. there was no evidence for two mn2+ uptake syste ... | 1993 | 8380803 |
| biochemical properties of streptococcus sobrinus reisolates from the gastrointestinal tract of a gnotobiotic rat. | streptococcus sobrinus strain 6715-13-201 was inoculated into the oral cavity of a gnotobiotic rat and then reisolated from different portions of the gastrointestinal tract. fourteen isolates, selected on the basis of their colonial morphology, were then screened for their ability to adhere to saliva-coated hydroxyapatite (sha) in vitro, and their ability to produce extracellular polysaccharide from sucrose, and low ph in glucose broth. certain isolates were also tested for their cariogenic pote ... | 1993 | 8393069 |
| close association between streptococcus sobrinus in the saliva of young children and smooth-surface caries increment. | three hundred and thirty-eight children (age range 3-5 years) were examined for the presence of mutans streptococci in their saliva. they were divided into four groups according to the prevalent species that were isolated: (1) streptococcus mutans and streptococcus sobrinus group (s. mutans > or = 10(3) cfu/ml and s. sobrinus > or = 10(3) cfu/ml); (2) s. mutans group (s. mutans > or = 10(3) cfu/ml but s. sobrinus < 10(3) cfu/ml); (3) s. sobrinus group (s. sobrinus > or = 10(3) cfu/ml but s. muta ... | 1993 | 8402804 |
| expression and secretion of an arthrobacter dextranase in the oral bacterium streptococcus gordonii. | we have constructed a plasmid to express and secrete dextranase in the oral bacterium streptococcus gordonii. the dextranase gene from arthrobacter sp. strain cb-8 was linked to a promoter and a dna sequence encoding the signal peptide of streptococcus downei glucosyltransferase i (gtfi) followed by the escherichia coli rrnbt1t2 terminator and inserted in the shuttle vector pva838. s. gordonii transformed with this plasmid (pmnk-4) expressed and secreted mature arthrobacter dextranase. the trans ... | 1993 | 8406828 |
| comparison of aminopeptidase activities in four strains of mutans group oral streptococci. | in this study, native cells of streptococcus mutans va-29r and streptococcus rattus fa-1 displayed significantly higher aminopeptidase activity than did cells of streptococcus cricetus aht or streptococcus sobrinus 6715 toward the nitroanilide derivatives of leucine, alanine, methionine, arginine, and lysine. these differences in cellular aminopeptidase activity led us to investigate the subcellular localization of the aminopeptidase in these mutans group streptococci. following conversion of na ... | 1993 | 8418040 |
| the effect of different strontium concentrations on the efficacy of chlorhexidine-fluoride-strontium gel in preventing enamel softening in vitro. | the effects were compared of strontium concentrations of 0, 15, 50 and 250 parts/10(6) in chlorhexidine(0.20%)-fluoride(0.16%) gel in preventing the softening of bovine enamel during bacterial fermentation. fresh streptococcus sobrinus cells were suspended in a buffer solution (ph 6.0) with 3.3% sucrose and centrifuged as a plaque-like layer on the top of enamel slabs covered with 10 microliters gel. after 24 h incubation, the ph fall of the fluid was significantly smaller in all test groups tha ... | 1993 | 8476339 |
| nucleotide sequence analysis of the gtft gene from streptococcus sobrinus omz176. | the gtft gene and its upstream region isolated from the streptococcus sobrinus omz176 chromosomal dna were sequenced. the gtft gene was preceded by a potential shine-dalgarno sequence. the gtft gene product, glucosyltransferase (gtf), displays a typical gram-positive bacterial signal peptide sequence and both an active site peptide sequence and carboxy-terminal repeats typical of gtfs. the signal sequence is similar to those of other known gtf proteins. the putative active-site peptide sequence ... | 1993 | 8478099 |
| sequence analysis of scra and scrb from streptococcus sobrinus 6715. | the complete nucleotide sequences of streptococcus sobrinus 6715 scra and scrb, which encode sucrose-specific enzyme ii of the phosphoenolpyruvate-dependent phosphotransferase system and sucrose-6-phosphate hydrolase, respectively, have been determined. these two genes were transcribed divergently, and the initiation codons of the two open reading frames were 192 bp apart. the transcriptional initiation sites were determined by primer extension analysis, and the putative promoter regions of thes ... | 1993 | 8500898 |
| simultaneous caries induction and calculus formation in rats. | weanling specific pathogen-free osborne-mendel rats were fed a high-calcium, high-phosphorus diet with various levels of sucrose and inoculated with streptococcus sobrinus strain 6715-13wt and actinomyces viscosus strain omz-105 in order to determine whether calculus and caries could develop simultaneously. rats consumed diets designated rc-16-5, rc-16-25, or rc-16-50 which partially replaced the corn starch component with progressively higher levels of sucrose, thus, to 5, 25, or 50% sucrose. i ... | 1993 | 8501282 |
| effects of fluoxetine on the oral environment of bulimics. | the purpose of this study was to evaluate in a double-blind placebo-based study the effects of fluoxetine over a period of 16 weeks on the frequency of binging and purging and on fluctuations in the levels of cariogenic organisms and saliva secretion rate of patients (n = 30) with bulima nervosa. profile analysis suggested that, over the course of the study, binging and purging frequency and streptococcus sobrinus salivary levels decreased significantly in the fluoxetine group as compared with t ... | 1993 | 8510986 |
| effects of n-acetylglucosamine on carbohydrate fermentation by streptococcus mutans nctc 10449 and streptococcus sobrinus sl-1. | we have investigated the ability of two species of streptococci isolated from the human oral cavity (streptococcus mutans nctc 10449 and streptococcus sobrinus sl-1) to metabolize n-acetylglucosamine (glcnac), a naturally occurring amino sugar present in saliva and human glycoproteins, when provided as the sole fermentable carbohydrate and determined the effects of the presence of glcnac on the fermentation of other carbohydrates. s. mutans used glcnac at concentrations of up to 10 mm to increas ... | 1993 | 8418050 |
| a microbiological study of primary root-caries lesions with different treatment needs. | samples of altered or carious dentin for microbiological culture were obtained from 301 primary root-caries lesions in 59 patients by means of a standardized sampling procedure. this involved the cleansing of each root surface of extraneous supragingival plaque by means of a hand-held toothbrush and distilled water and the collection of the sample with a sterile dental excavator passed through the entire vertical dimension of each lesion. the total number of colony-forming units (cfu) in each sa ... | 1993 | 8450122 |
| the use of a caries detector dye during cavity preparation: a microbiological assessment. | during cavity preparation conventional tactile and optical criteria are used to assess the caries status of the enamel-dentine junction, cavity preparation being considered complete when this area is hard to a sharp probe and stain free. in the present study 201 cavities were prepared under rubber dam. when caries removal was considered complete using the conventional tactile and optical criteria, a caries detector dye (1% acid red in propylene glycol), which is claimed to stain 'infected' tissu ... | 1993 | 8461203 |
| antigenicity and immunogenicity of a synthetic peptide derived from a glucan-binding domain of mutans streptococcal glucosyltransferase. | the immunogenicity and antigenicity of a multiply antigenic peptide construct containing four copies of the synthetic peptide tgaqtikgqklyfkangqqvkg were measured in rodents and humans, respectively. the composition of this peptide construct (termed glu) was derived from a major repeating sequence in the c-terminal region of mutans streptococcal glucosyltransferases that synthesize water-insoluble glucan (gtf-i). the glu peptide elicited high levels of serum immunoglobulin g antibody to glu afte ... | 1993 | 8514393 |
| immune responses to streptococcus sobrinus surface protein antigen a expressed by recombinant salmonella typhimurium. | in this study, we used a vaccine strain of salmonella typhimurium to express antigenic determinants of the spaa antigen of streptococcus sobrinus, which is involved in the caries-forming process. we cloned either a single repeat (pya2901) or three tandem repeats (pya2905) of the 0.48-kb fragment of the spaa gene, which codes for an important component of the spaa protein, plus a 1.2-kb minor antigenic determinant and measured the resulting immune responses to spaa in orally immunized balb/c mice ... | 1993 | 8478075 |
| effects of xylitol/sorbitol combinations on bacterial growth and metabolism in streptococcus sobrinus omz 176. | combinations of the non-cariogenic sugar alcohols xylitol and sorbitol are widely used as sucrose substitutes in lozenges and chewing-gums. in s. sobrinus omz 176 xylitol inhibits the metabolism of sorbitol, and the xylitol-induced bacterial growth inhibition of s. sobrinus omz 176 has been shown to be enhanced by sorbitol. in combination with xylitol the sorbitol transport changes from a pts- to a non-pts transport, while the transport of xylitol is unaffected by the presence of sorbitol. it wo ... | 1993 | 8110450 |
| effects of selected surfactants on purified glucosyltransferases from mutans streptococci and cellular adherence to smooth surfaces. | the inhibitory effect of non-ionic, anionic, cationic and ampholytic surfactants on cellular growth of streptococcus mutans mt8148 and s. sobrinus 6715, on glucan synthesis by the purified glucosyltransferase (gtase) from these organisms, and on bacterial adherence to glass surfaces was examined in vitro. cationic surfactants exhibited marked bactericidal activities. anionic and ampholytic compounds were less strongly bactericidal and non-ionic surfactants produced only slight inhibition of cell ... | 1993 | 8418294 |
| escherichia coli heat-labile toxin subunit b fusions with streptococcus sobrinus antigens expressed by salmonella typhimurium oral vaccine strains: importance of the linker for antigenicity and biological activities of the hybrid proteins. | a set of vectors possessing the genes for aspartate semialdehyde dehydrogenase (asd) and the b subunit of the heat-labile enterotoxin of escherichia coli (lt-b) has been developed. these vectors allow operon or gene fusions of foreign gene epitopes at the c-terminal end of lt-b. two groups of vectors have been constructed with and without leader sequences to facilitate placing of the foreign antigen in different cell compartments. two streptococcus sobrinus genes coding for principal colonizatio ... | 1993 | 8432584 |
| four different types of glucans synthesised by glucosyltransferases from streptococcus sobrinus. | four different kinds of glucosyltransferases (gtfs) were purified from the cariogenic bacterium streptococcus sobrinus aht. one of them (gtfp3) produced water-insoluble glucan with the alpha-1,3 linkage, exclusively. the others (gtfp1, p2 and p4) produced water-soluble glucans. gtfp2 produced oligosaccharides with linear 1,6-alpha-d-glucan structure. since gtfp1 and p4 produce similar molecular weight glucans, the structural differences between these glucans remain unclear. to clarify the differ ... | 1993 | 8441354 |
| effect of monoclonal antibodies on the colonization of rats by streptococcus sobrinus. | local passive immunization has been suggested as a method of preventing colonization of teeth by mutans streptococci. in this study we describe the effect of local application of monoclonal antibodies (mabs) on the colonization of streptococcus sobrinus. the rats, 37 days old, were divided in 4 groups: group 1 received mab omvu10 (mab reactive with antigen b of s. sobrinus, igg2b), group 2 received clone 24 (mab reactive with lipid a of escherichia coli, igg2b), group 3 received uninoculated cul ... | 1993 | 8448771 |
| a simple method for monitoring mutans streptococci in margins of restorations. | plaque material collected from margins of restorations using a sharp toothpick was streaked across one and the same plastic strip from a commercially available test kit and inoculated in a liquid medium containing bacitracin. the reproducibility of the method was good. the method is simple, inexpensive and suitable for the chairside demonstration of the colonization of mutans streptococci in localized areas of the mouth, such as margins of restorations. | 1993 | 8354746 |
| 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. | 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 simil ... | 1993 | 8359882 |
| in vitro demineralization by strains of actinomyces viscosus and streptococcus sobrinus of sound and demineralized root surfaces. | root sections were inoculated with one of two strains of actinomyces viscosus or a strain of streptococcus sobrinus and then incubated for 9 days in trypticase soy broth (tsb) containing 0.25% glucose or tsb supplemented with 0.25% sucrose (tsb+s). lesion progression was measured from microradiographs. one section from each group was examined with a transmission electron microscope. lesion progression was associated with a fall in the ph of the medium. however, lesion progression was not correla ... | 1993 | 8360359 |
| protective effect of topically applied fluoride in relation to fluoride sensitivity of mutans streptococci. | the aim of the present in vitro experiments was to determine whether the protection of enamel by topically applied fluoride against demineralization by bacterial acids would depend on the fluoride sensitivity of the bacteria. glucose-agarose gel suspensions of fluoride-sensitive and fluoride-resistant mutans streptococci were placed on bovine enamel specimens with different amounts of fluoride. one group of specimens was untreated, a second group had been pretreated with a f-lacquer, and a third ... | 1993 | 8360360 |
| a longitudinal study of dental caries and cariogenic microflora in a group of young adults from göteborg. | caries and cariogenic microorganisms were assessed in a group of young adults over a 3-year period. a 30% random sample comprising 101 individuals aged 18-19 years was re-examined under conditions consistent with the baseline survey 3 years earlier. the means for dfs prevalence and increment were 8.9 and 2, respectively. continuing polarization of the disease was observed, with mean dfs score reaching 19.9 in the upper 15% of the frequency distribution. highest caries activity was observed appro ... | 1993 | 8291028 |
| grouping of oral streptococcal species using fourier-transform infrared spectroscopy in comparison with classical microbiological identification. | the grouping and identification made by fourier-transform infrared spectroscopy (ft-ir) of 40 oral streptococcal strains was compared with their known taxonomic positions. grouping was obtained by cluster analysis on the spectral distances between the first derivative spectra of the strains. spectra were divided into five spectral 'windows' and cluster analysis was either on either a combination of all five windows or on a selected window. the oral streptococci were divided into two main cluster ... | 1993 | 8297255 |
| identification and characterization of a mobilization gene in the streptococcal plasmid, pva380-1. | the 4.2-kb cryptic streptococcal plasmid, pva380-1, has a broad host range and replicates via a rolling circle mode. the nucleotide base sequence of the 2.5-kb basic replicon of this plasmid, containing a plus origin, a minus origin, and a rep gene, was reported previously. the completed nucleotide base sequence of pva380-1 revealed the presence of two additional open reading frames, orf2 and orf3. the protein predicted by orf2 shared 74% amino acid identity with the mob protein of the group b s ... | 1993 | 8302939 |
| agglutination of streptococcus mutans serotype c cells but inhibition of porphyromonas gingivalis autoaggregation by human lactoferrin. | the ability of various forms of human lactoferrin (lf) to agglutinate oral streptococcus mutans, strep. sobrinus, strep. rattus, strep. sanguis, porphyromonas gingivalis and actinobacillus actinomycetemcomitans cells was studied spectrophotometrically. fe3+ saturated lf was unable to agglutinate these bacteria, whereas iron-free lf (apo lf) effectively agglutinated strep. mutans cells but not the other bacteria. the efficiency and rate of agglutination of strep. mutans were somewhat lower with a ... | 1993 | 8387771 |
| phenotypic characterization of oral streptococci by classical methods. | the phenotypic characteristics of 215 strains of oral streptococci were compared on the basis of the results of sorbitol, raffinose and trehalose fermentation, ammonium from arginine production, aesculin hydrolysis, h2o2 production, susceptibility to 2 u bacitracin, and growth in 4% nacl solution. eleven different species were identified. among the most noteworthy findings were the low number of h2o2-producing strains of streptococcus sobrinus, the effective discrimination between streptococcus ... | 1993 | 8264436 |
| [experimental study on the interaction of fibronectin with oral streptococci]. | interaction of fibronectin (fn) with streptococcus mutans, s. sorbrinus, and s. milleri is demonstrated by an enzyme-linked immunosorbent assay (elisa). the results show that the three strains are able to adhere to fn. the interaction may be strengthened while the concentration of fn increases (q test p < 0.01). the ability of adherence among s. mutans, s. sorbrinus and s. milleri is different in fn high concentration (q test p < 0.01). it is speculated the free fn in saliva may serve as an aggl ... | 1993 | 8275808 |
| identification of antigenic epitopes in an alanine-rich repeating region of a surface protein antigen of streptococcus mutants. | a surface protein antigen (pac) of streptococcus mutans with a molecular mass of 190 kda is considered to play an important role in the initial attachment of this streptococcus to the tooth surface. two internal repeating amino acid sequences are present in the pac molecule. one repeating region located in the n-terminal region is rich in alanine (a-region), and the other, located in the central region, is rich in proline (p-region). to identify antigenic epitopes on the a-region of the pac prot ... | 1993 | 7681043 |
| cloning of a streptococcus sobrinus oligo-isomaltosaccharide synthase gene and characterization of its product. | a streptococcus sobrinus gene coding for a glucosyltransferase (gtf)-s was cloned into escherichia coli, using the bacteriophage lambda l47.1 and the plasmid vector pacyc184. the md124 clone obtained expressed a 155 kda gtf-s which did not react with any antisera against gtf-s1, -s2 and -i enzymes. the recombinant enzyme (designated rgtf-s3) was homogeneously purified from the md124 cell-extract and characterized. the purified rgtf-s3 synthesized primer-independently alpha-1,6-linked linear olig ... | 1993 | 8193601 |
| the effect of glass-ionomer cement on carious dentine: an in vivo study. | the effect of a glass-ionomer cement sealant on carious dentine was investigated clinically and bacteriologically. the study group consisted of 24 molar teeth, with small clinical visible occlusal dentine lesions, in 13 children (aged 7-18 years). twenty of these molars were filled and sealed with a glass-ionomer cement (fuji ionomer type iii) and 4 with a resin sealant (delton). from each molar, two dentine samples were collected aseptically with a time interval of 7 months. the first sample wa ... | 1993 | 8242680 |
| immunoglobulin a antibody activity to mutans streptococci in parotid, submandibular and whole saliva. | antigen extracts of 9 strains of streptococcus mutans, streptococcus sobrinus, streptococcus salivarius and streptococcus mitis were separated in acrylamide gels by electrophoresis. strains of the same genotype of mutans streptococci were found to have virtually identical sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns but differed clearly from other genotypes of mutans or with the reference strains s. salivarius and s. mitis. immunoglobulin a (iga) antibody activity to antige ... | 1992 | 1299799 |
| antimicrobial effect of a dental varnish, in vitro. | the effects of a polymer based antimicrobial releasing varnish cervitec were investigated against different gram-positive and gram-negative bacterial strains as well as a yeast using the agar diffusion inhibitory test (adt-test in vitro). as positive controls a 1% chlorhexidine gel and 1% aqueous solution of thymol and a placebo polymer varnish without active agents were employed. the test experimental varnish containing 1% chlorhexidine and 1% thymol showed antimicrobial activity against all gr ... | 1992 | 1336221 |
| mode of photocatalytic bactericidal action of powdered semiconductor tio2 on mutans streptococci. | powdered semiconductor tio2 has a photocatalytic bactericidal capacity on some kinds of bacteria, but its mechanism still remains unclear. the mode of its photocatalytic bactericidal action on the mutans group of streptococci was investigated. powdered tio2 had a bactericidal capacity on all serotypes of mutans streptococci. streptococcus sobrinus aht was mainly used for these experiments. the most effective concentration of tio2 was about 1 mg ml-1 and, at this concentration, 10(5) colony-formi ... | 1992 | 1403378 |
| effect of gels containing stannous fluoride on oral bacteria--an in vitro study. | the purposes of this investigation were to evaluate and compare the antimicrobial effect of (1) twelve 0.4 per cent stannous fluoride (snf2) commercial products and (2) different concentrations of snf2 (range = 0.02 to 3.28 per cent). the antibacterial inhibitory effect of various snf2 gels was evaluated as to their effectiveness against oral plaque bacteria including strains of s. mutans, s. sanguis, s. sobrinus, a. viscosus, a. actinomycetemcomitans, and b. intermedius. when twelve different c ... | 1992 | 1444958 |
| effects of food preservatives on growth and metabolism of plaque bacteria in vitro and in vivo. | the aims of the present study were to assess the consumption of food preservatives during the last decades, and to study the effect of the preservatives, sorbic and benzoic acid, on growth and glycolysis of oral bacteria in vitro, and on acid formation by dental plaque in vivo. five consumption reports from the central bureau of statistics of norway were used to estimate alterations in consumption of staple food containing the two preservatives. a modified broth dilution method was used to deter ... | 1992 | 1465573 |
| noncariogenicity of erythritol as a substrate. | erythritol is a sugar alcohol produced by aureobasidium sp. from glucose. it is 75-80% as sweet as sucrose and is also nonhygroscopic. the aim of this study was to evaluate this sugar substitute from a cariological point of view. erythritol was neither utilized as a substrate for the lactic acid production nor for plaque formation of mutans streptococci (serotypes a-h) and certain oral microorganisms. it was not utilized for water-insoluble glucan synthesis or cellular adherence by glucosyltrans ... | 1992 | 1468100 |
| natural transmission of streptococcus sobrinus in rats: saliva and serum antibody responses to colonization. | one hundred and twenty weanling rats fed diet nih 2000 that were free of streptococcus sobrinus and other mutans streptococci were employed in this study. sixty rats were inoculated orally with s. sobrinus 6715. each infected rat (donor) was paired and housed with an uninfected recipient. saliva and serum samples were collected from 24 (12 donor and 12 recipient) rats at the baseline (day 0) and from groups of 12 recipients sacrificed on days 10, 24, 38, and 52, and the level of infection with s ... | 1992 | 1531814 |
| noncariogenicity of maltitol in specific pathogen-free rats infected with mutans streptococci. | the effect of maltitol on caries development was examined in an experimental caries system employing specific pathogen-free (spf) sprague-dawley rats. fourteen strains of oral streptococci, including mutans streptococci, did not utilize the maltitol nor produce sufficient acid to demineralize tooth enamel. furthermore, maltitol did not serve as a substrate for glucosyltransferases of either streptococcus mutans mt8148r or streptococcus sobrinus 6715 to synthesize water-insoluble glucan. maltitol ... | 1992 | 1533175 |
| on the mechanism of xylitol-dependent inhibition of glycolysis in streptococcus sobrinus omz 176. | 1. the mechanism of xylitol-dependent inhibition of glycolysis in streptococcus sobrinus omz 176 was investigated in aerobically and anaerobically grown cells. 2. glucose-stimulated glycolysis was followed polarographically, by radio-hplc-analyses of glycolytic intermediates, by measurement of atp generated, and spectrophotometric monitoring of extent of nad(p)+/nadph-status. 3. xylitol added to suspensions of s. sobrinus inhibited o2 uptake by approximately 20%, and led to a corresponding decre ... | 1992 | 1551465 |
| synergistic degradation of bovine serum albumin by mutans streptococci and other dental plaque bacteria. | mutans streptococci (streptococcus mutans and streptococcus sobrinus) exhibited low levels of proteolytic activity against the model protein substrate, fitc-labelled bovine serum albumin, when incubated alone. inclusion of other members of the dental plaque microflora in the assay usually resulted in marked increases in the degree of proteolysis and a high level of synergy. interactions between mutans streptococci and either streptococcus oralis or fusobacterium nucleatum gave rise to the greate ... | 1992 | 1555762 |
| effects of weight watchers' diet on salivary secretion rate, buffer effect and numbers of mutans streptococci and lactobacilli. | the aim of this investigation was to study how a change to the dietary regimen of the weight watchers' (ww) affected salivary secretion rate, buffer effect and number of cariogenic bacteria. thirty-three women joining the ww were saliva sampled at the evening prior the day of the start of the dietary regimen and after 4 and 8 wk on the dietary regimen. no significant changes were found regarding saliva secretion rate and buffer effect. a significant decrease of salivary numbers of mutans strepto ... | 1992 | 1574682 |
| latex agglutination test for detection of mutans streptococci in relation to dental caries in children. | a simple and rapid system based on a latex agglutination (la) reaction was devised for the detection of mutans streptococci in dental plaque. latex particles were sensitized with antibodies against whole cells of streptococcus mutans strains mt8148 (serotype c), mt703r (e) and omz175 (f) and strep. sobrinus strains b13 (d) and 6715 (g). these sensitized particles were agglutinated within a few minutes after addition of 1.0-10 ng serotype-specific antigen from the homologous organisms or the nitr ... | 1992 | 1622345 |
| the effects of sucralose, xylitol, and sorbitol on remineralization of caries lesions in rats. | the purpose of this study was to determine whether ingestion of sucralose, xylitol, sorbitol, or distilled water alone could enhance remineralization of early caries lesions in rats. rats were infected by streptococcus sobrinus, fed diet 2000 (ziegler brothers, gardners, pa) ad libitum for two weeks, and, in addition, were offered drinking water sweetened by sucrose (10% w/v). a group of rats terminated at this time displayed significant levels of sulcal and smooth-surface caries. the remaining ... | 1992 | 1607434 |
| adherence of oral streptococci to salivary glycoproteins. | we used an overlay method to study the ability of human salivary glycoproteins to serve as receptors for several strains of streptococci that colonize the oral cavity. parotid and submandibular-sublingual salivas were collected as ductal secretions, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and transferred to nitrocellulose membranes. the resulting blots were overlaid with [35s]methionine-labeled bacteria, and salivary components to which the bacteria bound were det ... | 1992 | 1729194 |
| adhesion of mutants streptococci to glass with and without a salivary coating as studied in a parallel-plate flow chamber. | deposition and adhesion to glass with and without a salivary coating in a parallel-plate flow chamber were studied with four strains of mutans streptococci. stationary-state adhesion of the strains to uncoated glass ranged from 0.3 x 10(6) cm-2 (streptococcus rattus hg218) to 12.7 x 10(6) cm-2 (streptococcus sobrinus hg1025) and generally decreased after saliva coating of the glass. the poor adhesion found for s. rattus hg218 to both uncoated and saliva-coated glass could be due to its relativel ... | 1992 | 1573082 |
| purification and properties of extracellular mutacin, a bacteriocin from streptococcus sobrinus. | mutacin mt6223, a cell-free bacteriocin produced by streptococcus sobrinus mt6223, was purified by ammonium sulphate precipitation, chromatofocusing with pbe 94 and column chromatography on sp sephadex c-25. the specific activity of the purified mutacin was increased 1950-fold with a recovery of 9.7%. the molecular mass of the purified mutacin preparation was estimated to be 6.5 kda. the mutacin activity was stable from ph 2-7, and was resistant to treatment at 100 degrees c for 20 min. it was i ... | 1992 | 1564438 |
| molecular analysis of a streptococcus mutans strain exhibiting polymorphism in the tandem gtfb and gtfc genes. | streptococcus mutans ua101, which was previously demonstrated to be highly cariogenic in gnotobiotic rats, exhibited much lower water-insoluble glucan (ig) synthetic activity compared with that of s. mutans gs5 and was unable to express sucrose-dependent colonization of smooth surfaces in vitro. on the basis of southern and western blot (immunoblot) analyses, it was demonstrated that, unlike most s. mutans strains, strain ua101 contained a single copy of a gene coding for ig synthesis. the gene ... | 1992 | 1532167 |
| sodium hypochlorite disinfection of irreversible hydrocolloid impression material. | alginate impression material is one of the most frequently used in dentistry. however, this material is susceptible to dimensional distortion during disinfection because of its hydrophilic nature. this study examined the effects of alginate disinfection using a sodium hypochlorite spray or impression immersion. spray disinfection of an alginate impression did not cause dimensional differences of the poured stone casts when compared with casts from water-rinsed controls. immersion disinfection cr ... | 1992 | 1527745 |
| effects of tung oil on salivary viscosity and extent and incidence of dental caries in rats. | increased salivary viscosity may be associated with an increase in dental caries. in order to examine this relationship, the caries level in rats was monitored following gastric intubation with tung oil which has been shown to significantly increase salivary viscosity. tung oil intubation over an 8-week period significantly increased the salivary viscosity in rats as compared with deoinized water and corn oil intubation. the total number of carious lesions was significantly increased (p less tha ... | 1992 | 1521305 |
| odontoblast-mediated regulation of the progression of dentinal caries. | osteoblasts and odontoblasts are both derived from the same mesenchymal cell line. our aim was to investigate whether the processes of bone destruction and dentinal caries are biologically similar. the working hypothesis was that after the initiation of caries in the enamel, its rate of progression in the dentine is regulated by cell-mediated factors. experimental caries was induced in the rat with a high sucrose diet combined with streptococcus sobrinus infection. both destruction of dentine an ... | 1992 | 1508887 |
| genetic analysis of scra and scrb from streptococcus sobrinus 6715. | a dna fragment containing scra and scrb, which encode enzyme ii of the phosphoenolpyruvate-dependent sucrose phosphotransferase system and sucrose-6-phosphate hydrolase, respectively, was isolated from a lambda gt10 genomic dna library of streptococcus sobrinus 6715. both genes were located on a 4.2-kb dna fragment which was maintained stably in escherchia coli on low-copy-number vector pgb2. the recombinant e. coli clone expressed sucrose-hydrolytic activity on macconkey agar base supplemented ... | 1992 | 1500184 |
| dye-mediated bactericidal effect of he-ne laser irradiation on oral microorganisms. | little attention has been given to the bactericidal effect of laser irradiation, particularly using low-power energy lasers. it has been demonstrated that he-ne laser light has an inhibitory action on dental plaque. the purpose of this study was to investigate the bactericidal effect of he-ne laser irradiation on cariogenic microorganisms. the bactericidal effect was determined by the formation of a growth-inhibitory zone or by the counting of viable bacterial colonies. streptococcus sobrinus ah ... | 1992 | 1495373 |
| reduced nicotinamide adenine dinucleotide oxidase involvement in defense against oxygen toxicity of streptococcus mutans. | the growth inhibition of the streptococcus mutans group, including streptococcus mutans, streptococcus cricetus, streptococcus rattus and streptococcus sobrinus, on glucose by oxygen and the properties of reduced nicotinamide adenine dinucleotide (nadh) oxidase induced by oxygen, using a representative oxygen-tolerant strain, were examined. the growth response to oxygen varied among strains and correlated with the level of nadh oxidase activity in the cell extract. the induced synthesis of nadh ... | 1992 | 1494456 |
| mutans streptococci, lactobacilli and caries prevalence in 15 to 16-year olds in göteborg. part ii. | during the fall of 1987 one hundred and fifty-five 15 to 16-year-olds were examined with regard to caries prevalence, saliva secretion rate and salivary numbers of mutans streptococci and lactobacilli. in 15% of the subjects no mutans streptococci were detected, while 17.7% carried > 10(6) colony forming units (cfu) per ml saliva. the median value was 1.8 x 10(5) cfu per ml saliva. no lactobacilli were detected in 19% of the subjects and 14.3% had > 10(5) cfu per ml saliva. the mean caries preva ... | 1992 | 1481133 |
| the effect of phenytoin medication on dentin apposition, root length, and caries progression in rat molars. | to determine the effect of phenytoin (pht) on dentin apposition and the rate of caries progression in dentin, 40 wistar rats were treated daily for 35 days with intraperitoneal injections of 5,5-diphenylhydantoin. twenty-eight controls received saline with ph adjusted to that of pht. one pht and one control group were fed a 43% sucrose diet, and the others a non-cariogenic pellet diet. streptococcus sobrinus was inoculated to induce caries. schiff staining was used to determine caries. the areas ... | 1992 | 1476051 |
| the effect of ovariectomy on dentin formation and caries in adult rats. | since acute osteoporosis is known to enhance bone remodeling and osteoid formation, it may also affect dentin apposition. we induced osteoporosis in 15-week-old wistar rats by ovariectomy and dental caries by streptococcus sobrinus infection in the presence of either a high sucrose (cariogenic) diet or a non-cariogenic diet. intact animals with the same diets served as controls. after 99 days of cariogenic challenge the rats were killed, and the success of ovariectomy was confirmed by failure to ... | 1992 | 1476050 |
| evaluation of the cariogenic potential of the intense natural sweeteners stevioside and rebaudioside a. | stevioside and rebaudioside a, two intense natural sweeteners, that are constituents of the south american plant stevia rebaudiana, were tested for cariogenicity in albino sprague-dawley rats. sixty rat pups colonized with streptococcus sobrinus were divided into four groups and fed stevioside, rebaudioside a or sucrose added to basal diet 2000 as follows: group 1, 30% sucrose; group 2, 0.5% stevioside; group 3, 0.5% rebaudioside a, and group 4, no addition. all four groups were sacrificed after ... | 1992 | 1468101 |
| an 87-kilodalton glucan-binding protein of streptococcus sobrinus b13. | an 87-kda glucan-binding protein (gbp) of streptococcus sobrinus b13 (serotype d) was isolated and purified from extracellular culture supernatant by using affinity chromatography on sephadex g-50 and elution with a guanidine hcl gradient. western blot (immunoblot) analysis showed it to be antigenically related, but not completely identical, to the 74-kda gbp of streptococcus mutans ingbritt. the 87-kda gbp has no glucosyltransferase activity. a possible role for this gbp in the cariogenicity of ... | 1992 | 1452362 |
| effects of chlorhexidine-fluoride gel treatments in mothers on the establishment of mutans streptococci in primary teeth and the development of dental caries in children. | in a longitudinal 3-year study, 151 children were followed for the colonization of the primary dentition by mutans streptococci (ms) and for the development of dental caries. at the age of 1 year, the child-mother pairs were divided into three groups on the basis of the levels of ms in maternal saliva. in the experimental group, the mothers had ms levels higher than 10(5) cfu/ml, and they were given chlorhexidine (1%)-sodium fluoride (0.2%) gel treatments twice a year for 3 years. two control gr ... | 1992 | 1423442 |
| mechanism of water-insoluble glucan synthesis in streptococcus sobrinus. | synthesis of water-insoluble glucan (ig) by 1,3-alpha-d-glucan synthase from streptococcus sobrinus was examined using methylation analysis. the purified enzyme was incubated with sucrose and dextran t2000 (dt2000) for a given time and only ig was harvested by centrifugation. the remaining supernatant was incubated again, and ig was obtained. by repeating the above method using the residual supernatant, we obtained 5 varieties of ig precipitated in different periods. these igs were methylated an ... | 1992 | 1408351 |
| viability of streptococcus mutans and streptococcus sobrinus in whole saliva with varying concentrations of indigenous antimicrobial agents. | we have studied the possible relationship between indigenous salivary antimicrobial agents, indigenous mutans streptococci and the capability of added mutans streptococci to grow in saliva. stimulated whole saliva was collected from 19 healthy donors. saliva samples were sterilized, supplemented with glucose and inoculated with streptococcus mutans or streptococcus sobrinus. the mixtures were incubated for 20 h followed by counting of viable cells. saliva samples were analysed, both before and a ... | 1992 | 1334804 |
| [detection of dna g+c mol% in taxonomy of streptococcus mutans by means of high performance liquid chromatography]. | in the present study, dna g+c mol% of 9 strains of bacteria (including 7 international standard strain, ingbritt, and 2 other strains extracted in our lab) were detected with application of high performance liquid chromatograph. the results showed that dna g+c content of s. mutans was 35-40%, s. sobrinus was 45-46%, s. cricetus was 38%, and s. rattus was 41%. the difference between s sobrinus and s. mutans was higher than 5%, which suggested that s. sobrinus should be identified as an independen ... | 1992 | 1307950 |
| effects of phenytoin on dental caries and plaque in streptococcus sobrinus-infected rats. | effects of phenytoin (pht) administration on dental caries in rats infected with streptococcus sobrinus 6715 were investigated. twenty-day-old specific pathogen-free fischer male rats were infected with s. sobrinus 6715 and fed diet 2000 containing 56% sucrose with or without pht for 52 days. antibody responses against anti-s. sobrinus in serum and saliva failed to show a statistical difference between pht-treated and nontreated rats. these results indicate that pht treatment increased plaque de ... | 1992 | 1303536 |
| mutans streptococci and lactobacilli in breast-fed children with rampant caries. | this study aimed to investigate the prevalence of selected components of the oral microflora in breast-fed children who developed rampant caries (resembling nursing caries) under hitherto unexplained circumstances. dental plaque and saliva samples were collected from breast-fed children, aged between 1 and 2.5 years, with and without rampant caries. mutans streptococci and lactobacilli were isolated from dental plaque of all children with rampant caries and from most caries-free children. none o ... | 1992 | 1628292 |
| inhibitory effects of ellagic acid on glucosyltransferases from mutans streptococci. | ellagic acid and its derivatives were found to abrogate the enzymatic activity of the glucosyltransferases (gtases) of mutans streptococci. these compounds preferentially inhibited the water-soluble glucan synthesis by gtase of streptococcus mutans mt8148 and inhibited the water-insoluble glucan synthesis by gtase of streptococcus sobrinus 6715. this inhibition resulted in a reduction of cellular adherence of mutans streptococci to a glass surface. | 1992 | 27286205 |
| sequence and structural analysis of surface protein antigen i/ii (spaa) of streptococcus sobrinus. | streptococcal antigen i/ii or the surface protein antigen a (spaa) of streptococcus sobrinus is an adhesin which mediates binding of the organism to tooth surfaces. the complete sequence of the gene which encodes spaa has been determined. the gene consists of 4,584 bp and encodes a protein of 1,528 amino acid residues. the deduced amino acid sequence shows extensive homology with those of the cell surface adhesins from streptococcus mutans serotypes c and f and from streptococcus sanguis. struct ... | 1991 | 1855987 |
| interactions of sanguinarine and zinc on oral streptococci and actinomyces species. | sanguinaria extract, which contains benzophenanthridine alkaloids, has been used as a folk medicine for many years. minimum inhibitory and minimum bactericidal concentrations (mic and mbc values) for sanguinarine were determined for common and etiologically important plaque bacteria. because the efficacy of sanguinarine is believed to be enhanced by zinc, isobolograms were assessed to determine their mode(s) of interaction. hydrogen ion concentration influenced the inhibitory activity of both sa ... | 1991 | 1878916 |
| the extension of alpha-d-1,3-branch linkages by 1,3-alpha-d-glucan synthase from streptococcus sobrinus. | in the presence of an acceptor, 1,3-alpha-d-glucan synthase of streptococcus sobrinus synthesizes water-insoluble glucans from sucrose. under such conditions, 1,3-alpha-d-glucoside linkages were extended without any change in the glucose-residue number between the 1,3,6-branch points on the acceptor. from these results, the mechanisms of water-insoluble-glucan formation were proposed as follows: (i) the attachment of an acceptor to the glucan binding sites of 1,3-alpha-d-glucan synthase occurs d ... | 1991 | 1838088 |
| partial characterization of the glucosyltransferases of an oral streptococcus salivarius strain. | the oral streptococcus salivarius strain s3 possessed extracellular glucosyltransferase (gtf) and cell-associated fructosyltransferase activities. chromatofocusing column chromatography of crude gtf yielded multiple peak fractions, which were categorized into two types which catalysed (1) water-insoluble glucan synthesis and (2) water-soluble glucan formation. the gtf isozyme eluted in fraction 29 synthesized mutanase- and dextranase-sensitive insoluble glucan from sucrose, while fraction 81 gtf ... | 1991 | 1839049 |
| complete nucleotide sequence of the gene for a surface protein antigen of streptococcus sobrinus. | the complete nucleotide sequence of the gene for a cell surface protein antigen (spaa) of streptococcus sobrinus mt3791 (serotype g) was determined. the spaa gene consisted of 4,698 bp and coded for a protein of 170,202 da. a putative signal peptide was found in the amino-terminal end of the protein. a potential promoter sequence and a putative shine-dalgarno sequence preceded the open reading frame. two internal repeating amino acid sequences were present in spaa. one repeating region, located ... | 1991 | 1840575 |
| [caries-inducing activity of soybean-oligosaccharide (sor) in vitro and in experimental dental caries of rats]. | the caries-inducing activity of soybean-oligosaccharide (sor: stachyose- and raffinose-rich sugar mixture) was examined in in vitro and in vivo experiments. streptococcus mutans mt 8148r fermented sor and produced acids. however streptococcus sobrinus 6715 did not ferment. sor was not able to act as a substrate for crude glucosyltransferases (gtase) of these mutans streptococci to synthesize the water-insoluble glucan. however, sor did not inhibit the synthesis of water-insoluble glucan from suc ... | 1991 | 1784869 |
| salivary levels of mutans streptococci and lactobacilli in dentate 80- and 85-year-old swedish men and women. | the number of streptococcus mutans, streptococcus sobrinus, and lactobacilli in whole stimulated saliva was examined in 130 dentate 80- and 85-yr-old persons. 88.5% were positive for mutans streptococci and 29% carried greater than 10(6) cfu per ml saliva. s. mutans was most frequently isolated and was found in 114 persons (88%) alone or in combination with s. sobrinus. s. sobrinus was detected in 33 persons (25%), who also showed significantly higher salivary numbers of both mutans streptococci ... | 1991 | 1764902 |
| some properties of an endodextranase inhibitor from continuous cultures of streptococcus sobrinus. | cell-free filtrates of streptococcus sobrinus, cultured at low growth rate in the chemostat, contain a dextranase inhibitor that can completely inhibit the activity of s. sobrinus endodextranase. the range of conditions under which inhibition occurs, and the situations in which enzyme activity can reappear, have been examined in continuous cultures of strain 6715-13wt and the dextranase-deficient mutant 6715-13-201. a purified preparation of the inhibitor was specific for s. sobrinus dextranase, ... | 1991 | 1669445 |
| inhibitory effect of stannous fluoride and other commonly used antimicrobial agents on oral bacteria. | the purposes of this investigation were to evaluate and compare the antimicrobial effect of stannous fluoride (snf2) gel and other commonly used oral antimicrobial agents/products. the antibacterial inhibitory effect of the various agents was evaluated by their effect against oral plaque bacteria including strains of streptococcus sanguis, streptococcus sobrinus, actinomyces viscosus, actinobacillus actinomycetemcomitans, bacteroides gingivalis and bacteroides intermedius. a lawn of the specific ... | 1991 | 1681003 |
| intracellular xylitol-phosphate hydrolysis and efflux of xylitol in streptococcus sobrinus. | the parental strain streptococcus sobrinus (streptococcus mutans atcc 27352), which is known to transport, phosphorylate and accumulate xylitol intracellularly as nonmetabolizable xylitol-phosphate (xylitol-sensitive (xs) strain) and its xylitol-resistant (xr) spontaneous mutant were used to further investigate the inhibitory action of xylitol on oral streptococci. fructose-grown xr cells did not accumulate xylitol-phosphate, indicating that the inducible fructose pts is incapable of transportin ... | 1991 | 1658712 |
| a simple biochemical scheme for the differentiation of streptococcus mutans and streptococcus sobrinus. | a collection of wild-type and reference strains of streptococcus mutans and streptococcus sobrinus was compared using a set of fermentation and enzymic tests in order to establish a simple scheme for the differentiation of these two species isolated from selective media. tests for the production of acid from n-acetylglucosamine, arbutin and melibiose, and the presence of alpha-galactosidase and alpha-glucosidase activities were useful in differentiating these species. strains of streptococcus mu ... | 1991 | 1652359 |
| peptide sequences for sucrose splitting and glucan binding within streptococcus sobrinus glucosyltransferase (water-insoluble glucan synthetase). | the gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (gtf-i) of streptococcus sobrinus (formerly streptococcus mutans 6715) was cloned, expressed, and sequenced. a gene bank from s. sobrinus 6715 dna was constructed in vector puc18 and screened with anti-gtf-i antibody to detect clones producing gtf-i peptide. five immunopositive clones were isolated, all of which produced peptides that bound alpha-1,6 glucan. gtf-i activity was found in only two large peptides: ... | 1991 | 1704006 |
| immunological relationships between glucosyltransferases synthesizing insoluble glucan from streptococcus cricetus, streptococcus sobrinus and streptococcus downei. | the mr values and isoelectric points of glucosyltransferases synthesizing insoluble glucan (gtf-is) were determined, and the immunological relationships between them studied. the gtf-i enzymes were from streptococcus cricetus (mutans group serotype a), streptococcus sobrinus (mutans group serotypes d and g) and streptococcus downei (mutans group serotype h). by double immunodiffusion tests, the gtf-i enzymes from the three species possessed a common antigenic determinant; in addition, the gtf-i ... | 1991 | 1720167 |
| cariogenicity of milchschnitte (ferrero gmbh) and apple in program-fed rats. | the cariogenicity of ferrero milchschnitte and apple was tested in rats using a frequency-controlled feeding machine. twelve litters of osborne-mendel rats orally infected with streptococcus sobrinus omz-176 and actinomyces viscosus ny-1 were used. four treatment groups were tested: (1) cooked starch/sucrose 1:1 as positive control; (2) ferrero milchschnitte; (3) apple; (4) gastric intubation only as negative control. groups 1-3 were additionally fed by gastric intubation with essential nutrient ... | 1991 | 1747885 |
| effect of calcium ions on cell surface electrostatics of bacteroides gingivalis and other oral bacteria. | surface electrostatics of bacteroides gingivalis and other oral bacteria were examined. a polarization circuit was employed using platinum electrodes exposed in each bacterial suspension and the number of bacteria adsorbed to the anode and cathode were then estimated. in all bacteria (b. gingivalis, streptococcus sobrinus, s. mutans, s. salivarius, s. sanguis and actinomyces viscosus), the number of cells adsorbed to the anode were much greater than the number of cells adsorbed to the cathode. t ... | 1991 | 1930564 |
| interactions between and within streptococcus mutans and streptococcus sobrinus isolated from humans harboring both species. | the prevalence of streptococcus mutans and streptococcus sobrinus was examined in plaque samples from small discrete areas of the buccal tooth surfaces of seven subjects. strains of s. mutans and s. sobrinus were isolated and tested for bacteriocin-mediated interactions between and within the two species, using the stab inoculation technique. s. mutans and s. sobrinus did not colonize each tooth surface uniformly and, in plaque from small discrete sites, s. mutans and s. sobrinus were either und ... | 1991 | 1763286 |
| in vitro antibacterial effect of chlorhexidine added to glass-ionomer cements. | the aims of the present study were to investigate the antibacterial properties of glass-ionomer cements containing different concentrations of chlorhexidine and the possible release of chlorhexidine from the compound. chlorhexidine gluconate or diacetate was mixed with glass-ionomer cements and tested in vitro against strains of lactobacillus casei and mutans streptococci. a spectrophotometric test was used to monitor the release of chlorhexidine from the mixture. in a broth culture test, the hi ... | 1991 | 1763290 |
| combined effects of zn(2+)-chlorhexidine and zn(2+)-cetylpyridinium chloride on caries incidence in partially desalivated rats. | the effects of zn2+ combined with either chlorhexidine or cetylpyridinium chloride (cpc) on caries incidence in partially desalivated rats were investigated. seven groups of 12 animals each received topical applications for 20 s with a saturated swab (0.2 ml) of the following aqueous solutions twice daily on weekdays (10 a.m. and 3 p.m.) and once daily during weekends (12 a.m.) for 5 wk: deionized water (placebo); 40 mm zinc acetate; 2.2 mm chlorhexidine diacetate; 4.4 mm cpc; 40 mm zinc acetate ... | 1991 | 1771376 |
| in vitro demineralization of enamel by f-sensitive and f-resistant mutans streptococci in the presence of 0, 0.05, or 0.5 mmol/l naf. | lactate production and accompanying enamel demineralization by fluoride-sensitive and fluoride-resistant mutans streptococci were studied in an in vitro demineralization model in the presence of 0, 0.05, or 0.5 mmol/l naf. the fluoride-resistant strains were derived from laboratory strains or were recently isolated strains from xerostomic patients on high-dose fluoride therapy. the demineralization model was composed of a cell suspension in a glucose-agarose gel overlying a bovine enamel block. ... | 1991 | 1774379 |
| in vitro acidogenic potential and mutans streptococci of human smooth-surface plaque associated with initial caries lesions and sound enamel. | samples of human dental plaque were pooled from several "white spot" smooth tooth surface areas as well as from several clinically-sound tooth surface areas in each of 12 caries-positive college students. each of the two samples from each subject was used for the determination of: (1) ph-lowering potential in vitro involving dispersed plaque suspensions, excess glucose supply, and a 60-minute test, and (2) the proportions of mutans streptococci and lactobacilli. when all subjects were considered ... | 1991 | 1774380 |
| microbiological and immunological aspects of experimental periodontal disease in rats: a review article. | animal models in which microbiological and immunological aspects of periodontal disease can be studied prospectively seem well warranted. the rat bears much resemblance to man with respect to periodontal anatomy, development and composition of dental plaque, histopathology of periodontal lesions, and basic immunobiology. furthermore, reproducible methods are available for assessment of periodontal disease in rats, and detectable periodontal destruction can be induced in a few weeks in these anim ... | 1991 | 2002433 |
| effects of chlorhexidine on proteolytic and glycosidic enzyme activities of dental plaque bacteria. | chlorhexidine was tested for its ability to inhibit a wide range of glycosidic and proteolytic enzyme activities produced by treponema denticola, porphyromonas gingivalis, bacteroides intermedius, actinobacillus actinomycemcomitans, capnocytophaga sputigena, capnocytophaga gingivalis, capnocytophaga orchracea, capnocytophaga sp., actinomyces viscosus, streptococcus mitior, streptococcus mutans, streptococcus sobrinus, streptococcus mitis, streptococcus anginosus, streptococcus oralis and strepto ... | 1991 | 2005230 |
| effect of variation in growth conditions on the activity of dextranase inhibitor in continuous cultures of streptococcus sobrinus. | the activity of free extracellular dextranase inhibitor was determined in strains of streptococcus sobrinus which were grown in a chemostat under a variety of defined conditions. maximum release of dextranase inhibitor occurred at low growth rate in glucose-limited medium at ph 6.5. free inhibitor could not be detected when the strains were grown at high growth rate or in batch culture. | 1991 | 2023543 |
| mutans streptococci and non-mutans streptococci acidogenic at low ph, and in vitro acidogenic potential of dental plaque in two different areas of the human dentition. | samples of human dental plaque were obtained from sound tooth surfaces in the lower anterior and upper posterior areas of each of 11 subjects with various degrees of caries experience. both types of plaque were compared for: (1) their ph-lowering potential [ph at 10 and 60 min after sugar addition and the ph drop between 0 and 10 min (delta ph)] with an in vitro method involving dispersed plaque suspensions and excess glucose supply; (2) the proportions of mutans streptococci; and (3) the distri ... | 1991 | 1774381 |
| transmission of mutans streptococci. | it has been shown that early establishment of mutans streptococci in the mouth of infants increases risk of caries. extensive studies on the timing of infection, and on sources and routes of transmission of the organism have been performed. results of many studies suggest that the source of mutans streptococci is the mother, especially her saliva. methods used to attempt to verify this hypothesis have developed considerably in recent years. recent research and work in progress using methods base ... | 1991 | 1775473 |
| antibody responses to mutans streptococci in children. | because mutans streptococci (streptococcus mutans, s. sobrinus) are considered the main causative bacteria in human dental caries, immune responses to these bacteria have aroused much research interest over the last two decades. studies in man have focused mainly on salivary and serum antibodies developing naturally in response to oral colonization by mutans streptococci, or in relation to the development of dental caries. although both salivary (iga) and serum-derived (igg) antibodies have been ... | 1991 | 1775474 |
| purification and characterization of recombinant cell surface protein antigen a of streptococcus sobrinus b13n. | 1. it has been reported that immunization of rhesus monkeys with the surface protein antigen i/ii from streptococcus mutans significantly reduced dental caries. 2. the surface protein antigen a (spaa) from streptococcus sobrinus is known to correspond antigenically to i/ii. md51 is an escherichia coli host containing pmd51, a plasmid encoding the spaa gene from streptococcus sobrinus b13n. 3. the recombinant spaa (rspaa) was purified from cell extracts of escherichia coli clone md51. 4. the puri ... | 1991 | 1786849 |
| comparison of the physicochemical surface properties of streptococcus rattus with those of other mutans streptococcal species. | mutans streptococci comprise a group of seven closely related, yet distinct species. the distinction between the four species used in this study, namely streptococcus sobrinus, streptococcus cricetus, streptococcus rattus, and streptococcus mutans, has been made only recently on the basis of dna homologies. in order to determine if there is a difference in the physicochemical surface properties of these species, strains were characterized by contact angles, zeta potentials and isoelectric points ... | 1991 | 1810653 |
| dental caries and mutans streptococci in the proximal areas of molars affected by the habitual use of xylitol chewing gum. | the relationship between the caries status and the microbiological status [mutans streptococci (ms)] in the proximal areas of lower right and upper left molars was investigated in subjects of the ylivieska xylitol study in finland (1982-1985) in a cross-sectional follow-up in 1988. those children who had used xylitol chewing gum regularly since 1982 showed significantly lower caries indices in 1988, including the proximal caries scores. the presence of ms (expressed in log10 colony-forming units ... | 1991 | 1810656 |
| effect of dentifrices containing either xylitol and glycerol or sorbitol on mutans streptococci in saliva. | in 76 adults, randomly distributed between two groups, a comparison was made of the effect on the level of mutans streptococci in saliva between two dentifrices containing: (1) xylitol (9.9%) and glycerol (20%) or (2) sorbitol (28%) as humectants. after the use of the dentifrices twice daily for 3 months, the levels of mutans streptococci had not changed significantly in the sorbitol-treated group, whereas a significant reduction (p less than 0.0005) was found in subjects using the xylitol/glyce ... | 1991 | 1810657 |
| fluoride and mutans streptococci in plaque grown on glass ionomer and composite. | the aim of this study was to compare the levels of fluoride and mutans streptococci in plaque grown on glass ionomer (ketac-fil) and composite (silar) restorations in vivo. from tunnels left under the brackets bonded either with glass ionomer or composite, 14-day-old plaque samples were collected 14, 28, and 42 days after bonding. for glass ionomer the mean counts of mutans streptococci in plaque were 0.5 x 10(3), 6.7 x 10(3), and 8.8 x 10(3) cfu at the first, second, and third collection, respe ... | 1991 | 1810658 |
| chain formation and de-chaining in streptococcus sobrinus sl-1. | regulation of chain length by chain-forming bacteria is believed to depend on wall-associated autolytic activity and environmental conditions. in this study, the chain length of streptococcus sobrinus sl-1 was determined under various initial culture and ph conditions and naf concentrations. crude wall extracts were prepared by dilute alkali treatment of whole cells and were tested for de-chaining activity. the results indicate that s. sobrinus sl-1 grows primarily as short chains under alkaline ... | 1991 | 1820572 |