SEARCH · PubMed Health

Results for “Streptococcus sobrinus”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

PubMed1998

Five-year incidence of caries, salivary and microbial conditions in 60-, 70- and 80-year-old Swedish individuals.

The 5-year incidence of dental caries in a random sample of 60-, 70- and 80-year-old inhabitants of Goteborg was related to salivary and microbial conditions. Of the 208 persons examined at baseline, 148 (71%) participated in the follow-up examination; 69, 51 and 28, respectively, in the different age groups. The study revealed that 27% of the participants had not developed any carious lesions during the 5-year period and that the incidence of coronal and root caries increased with age. In the 60-year-olds, 2.5% of the susceptible coronal and root surfaces, respectively, had decayed, while the corresponding figures for the 80-year-olds were 8.8% for coronal surfaces and 9.8% for root surfaces. In all, 18% had an unstimulated saliva secretion rate of below 0.1 ml/min and 14% had a stimulated secretion rate of <0.7 ml/min, with a mean rate which decreased with increasing age from 2.0 to 1.6 and 1.3 ml/min (p = 0.02). The overall salivary counts of lactobacilli and mutans streptococci, particularly the subspecies of Streptococcus sobrinus, had increased during the period. In the respective age groups of 60, 70 and 80 years, 15, 39 and 39% had a mutans streptococci count of > or = 10(6) CFU/ml in saliva and the corresponding figures for > or = 10(5) lactobacilli counts were 22, 31 and 43%. In the stepwise regression analysis, it was found that age, salivary levels of mutans streptococci and lactobacilli and number of teeth were the best predictors of the incidence of root caries. In conclusion, these observations indicate that there is an increased risk of dental caries with age owing to unfavourable microbial and salivary conditions.

Age Factors↗

PubMed1994

Cariogenic potential of foods. II. Relationship of food composition, plaque microbial counts, and salivary parameters to caries in the rat model.

A series of rat caries experiments was carried out to test the relative cariogenic potential and to identify the major carcinogenic elements of 22 popular snack foods. Parameters that were measured included rat caries, number of cariogenic bacteria in plaque, salivary parameters including flow rate, buffering capacity, total protein, lysozyme and amylase content, and composition of test foods including protein, fat, phosphorus, calcium, fluoride, galactose, glucose, total reducing sugar, sucrose, and starch. Many interesting relationships were observed between food components, numbers of plaque bacteria, salivary components, and specific types of carious lesions. Protein, fat, and phosphorus in foods were all associated with inhibition of both sulcal and buccolingual (smooth-surface) caries. Food fluoride was associated with inhibition of buccolingual caries, whereas calcium was related to inhibition of sulcal caries. Glucose, reducing sugar, and sucrose in foods were all related to promotion of both sulcal and smooth-surface caries. The numbers of Streptococcus sobrinus in plaque were associated with promotion of smooth-surface caries only, whereas lactobacilli, non-mutans bacteria, and total viable flora were related to promotion of both smooth-surface and sulcal caries. The salivary flow rate was associated with inhibition of both buccolingual and sulcal caries. Salivary buffering capacity (at pH 7) and salivary lysozyme delivery were associated with inhibition of number and severity of sulcal caries, while the salivary amylase content was related to the promotion of the number of sulcal lesions.

Amylases↗

PubMed1995

Cariogenic bacteria in a longitudinal study of approximal caries.

Two hundred and seventeen approximal spaces, initially caries free, in 58 patients were studied clinically and radiographically, at intervals of 6 months, for 3 years. Samples of approximal dental plaque were removed for culture of Streptococcus mutans, Streptococcus sobrinus, and lactobacilli. During the study approximal caries developed in 16 subjects (27.6%) at 30 sites (13.8%), involving 42 teeth. 56 of 58 (96.7%) subjects harboured S. mutans at some time during the study, 62.1% lactobacilli, and 29.3% had S. sobrinus. The counts of S. mutans were significantly higher in those subjects that also carried S. sobrinus than in the remaining subjects. A persisting high count of S. mutans > 10(5) colony-forming units per millilitre (CFU/ml) or a count that rose by > or = 1 x log10 CFU/ml during the study was seen in 25 of 30 sites that subsequently became carious (p < 0.001). Similarly, counts of lactobacilli that were consistently > 10(3) CFU/ml or rising by > or = 1 x log10 CFU/ml were seen in 17 of 30 sites that became carious (p < 0.001). Although there were strong statistical associations between approximal caries and high or rising counts of these cariogenic bacteria, the bacterial counts were not good predictors of future approximal caries at that particular site.

Adolescent↗

PubMed1992

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 animals, for the ensuing three weeks, either continued on the same cariogenic challenge or received their essential nutrition by gavage and drank water, sweetened by one of the agents listed above, ad libitum. At the end of the additional three-week period, animals receiving sucralose, xylitol, sorbitol, or distilled water had fewer lesions than did the animals terminated after the two-week cariogenic challenge. The results show that removal of the cariogenic challenge allowed remineralization to occur and that no sweetening agent was superior to another in this respect.

Animals↗

PubMed1992

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 groups were formed. In control group 1, the mothers also had high levels of MS, but no gel was given. In control group 2, the mothers had low (< 10(5) CFU/ml) baseline levels of salivary MS, and no chlorhexidine-fluoride gel was used. In the total study population, 16, 42, and 54% of the children were colonized by MS by the age of 2, 3, and 4 years, respectively. Most children harbored only Streptococcus mutans, but 2 had both S. mutans and Streptococcus sobrinus, and 2 had only S. sobrinus. Twenty-eight percent of the MS-positive children developed caries by the age of 4 years, whereas 4 out of 27 children with dental caries did not have any detectable MS in their plaque samples. Both the colonization by MS and the caries incidence were highest in control group 1 and lower in the experimental group and in control group 2. These observations suggest that the reduction of maternal salivary MS at the time of tooth emergence may delay, or perhaps even prevent, the colonization of MS in the children's primary dentition with a concomitant decline in caries incidence, even in a population with an already low prevalence of dental caries.

Child, Preschool↗

PubMed1994

In vitro modulation of oral bacterial adhesion to saliva-coated hydroxyapatite beads by milk casein derivatives.

Bovine caseinate, derivatives of its glycosylated moiety [caseinoglycomacropeptide (CGP)], and caseinophosphopeptides were evaluated as inhibitors of adhesion of oral bacteria to saliva-coated hydroxyapatite beads (S-HA). All milk casein-derived components behaved as potent inhibitors of Streptococcus sanguis OMZ 9 and Streptococcus sobrinus OMZ 176 adhesion to S-HA, whereas neither bovine serum albumin nor polyethyleneglycol were able to interfere with the adhesion of these strains. By contrast, none of the molecular species tested was able to inhibit the attachment of Actinomyces viscosus Ny 1 to S-HA. On the other hand, casein derivatives were shown to displace human serum albumin from S-HA beads. They were also able to bind to the bacterial cell surface of all strains examined. Collectively, these findings suggest that interactions between acidic casein-derived milk components and the biological surfaces involved in bacterial adhesion to S-HA result in an inhibitory effect that is selective for the oral streptococci examined.

Actinomyces viscosus↗

PubMed2000

Modulation of glucan-binding protein activity in streptococci by fluoride.

Glucan-binding lectin (GBL) activity of Streptococcus sobrinus was significantly reduced by fluoride in the growth medium. Approximately 1.5 mM fluoride was required for a 50% reduction in GBL activity. In addition to the GBL, several other glucan-binding proteins were reduced when the bacteria were grown in subinhibitory fluoride. Fluoride had no effect on glucosyltransferases (GTFs), enzymes capable of converting sucrose into alpha-1,6-glucans. All the proteins were detected by use of enhanced chemiluminescence (ECL of fluorescein-labeled dextran) and Western blotting of renatured SDS-PAGE gels. The effects of fluoride on the bacteria were abrogated when the manganous ion was included in the growth medium. It thus appears that one mechanism of action of fluoridated water is its effects on glucan-binding proteins. The fluoride may be reducing metabolism of the mangano aquo ion, essential for expression of the glucan-binding proteins.

Blotting, Western↗

PubMed2002

Effects of apigenin and tt-farnesol on glucosyltransferase activity, biofilm viability and caries development in rats.

Propolis, a resinous hive product secreted by Apis mellifera bees, has been shown to reduce the incidence of dental caries in rats. Several compounds, mainly polyphenolics, have been identified in propolis. Apigenin and tt-farnesol demonstrated biological activity against mutans streptococci. We determined here their effects, alone or in combination, on glucosyltransferase activity, biofilm viability, and development of caries in rats. Sprague-Dawley rats were infected with Streptococcus sobrinus 6715 and treated topically twice daily as follows: (1) tt-farnesol, (2) apigenin, (3) vehicle control, (4) fluoride, (5) apigenin +tt-farnesol, and (6) chlorhexidine. Apigenin (1.33 mM) inhibited the activity of glucosyltransferases in solution (90-95%) and on the surface of saliva-coated hydroxyapatite beads (35-58%); it was devoid of antibacterial activity. tt-Farnesol (1.33 mM) showed modest antibacterial activity against biofilms and its effects on glucosyltransferases were minimal. The incidence of smooth-surface caries was significantly reduced by apigenin +tt-farnesol (60%), fluoride (70%), and chlorhexidine (72%) treatments compared to control (P < 0.05).

Analysis of Variance↗

PubMed1994

The effect of ovariectomy and high-sucrose diet on dentine formation and caries in growing rats.

Ovariectomized (Ovx) or sham-operated (Cnt) and tetracycline-labelled growing rats were fed either a commercial powdered standard rat diet (Ovx and Cnt) or a high-sucrose diet (Ovxsuc and Cntsuc). All animals were inoculated in the mouth with Streptococcus sobrinus. At 11 weeks of age the areas of caries lesions and dentinal apposition of the first and second molars and the areas of the pulpal cross-section of the incisors were determined. The area of dentinal apposition was largest in Cnt animals, the difference being statistically significant only in comparison with the Cntsuc animals. No such difference between the diets was found among the Ovx animals. The cross-section of the pulpal chamber was smallest in the Ovxsuc rats and largest in the Cnt animals, but no statistically significant differences were found between the groups. The caries lesions were significantly larger in Ovx, Ovxsuc and Cntsuc animals than in Cnt ones. Ovariectomy thus increased caries progression in growing rats, but the effect on dentine formation remained negligible. In this respect there is a difference between primary and secondary dentinogenesis.

Analysis of Variance↗

PubMedDate not supplied

Streptococcus mutans genotypes isolated from root and coronal caries.

The aim of the present study was to evaluate the colonization profile and clonal distribution of Streptococcus mutans isolated from oral cavities that presented coronal and root caries lesions. The isolation and biochemical identification of mutans streptococci were carried out by using saliva samples, dental plaque, and tissue from the caries lesions. In order to confirm their molecular identity, S. mutans and Streptococcus sobrinus were submitted to the PCR method, using specific primers for portions of the glucosyltransferase genes (gtfB and gtfI, respectively). The AP-PCR method was used to detect the genetic polymorphism of S. mutans strains. Among the isolated and identified species, S. mutans showed a significantly greater frequency of isolation (59.2%) than the other mutans streptococci. Each of the subjects harbored two to ten genotypes of S. mutans, randomly distributed in different sites. S. mutans genotypes showed no evidence of variability in colonizing noncarious and carious surfaces within the same individual, nor evidence of etiologic differences between coronal and root caries. This study showed that no particular genotype of S. mutans is uniquely associated with the initiation and progression of caries, and that root and coronal caries can emerge in the presence of a broad spectrum of S. mutans clones.

Aged↗

PubMed2003

Longitudinal study of intrafamilial mutans streptococci ribotypes.

To explore the intrafamilial homology and longitudinal stability of colonization by early acquired mutans streptococci, genomic fingerprinting was performed on 254 strains (192 Streptococcus mutans and 62 Streptococcus sobrinus strains) collected from 16 families (16 mother-child pairs, seven fathers and four siblings). Genomic DNA was digested by the restriction endonuclease HindIII, followed by gel electrophoresis, Southern blotting, and hybridization with a digoxigenin-labeled 16S rDNA probe, and hybrid detection by enhanced chemiluminescence. One to five ribotypes were identified per person, and between two and nine (median five) within each family. Fourteen of the 16 mother-child pairs showed homology for at least one ribotype (range 1-4). Six of the seven father-child pairs had one ribotype in common. Ten of the 13 longitudinally examined children showed persistence of at least one ribotype over a period of up to 16 yr. The results support the notion of intrafamilial transfer of mutans streptococci, and suggest that colonization of early acquired strains persists into young adulthood.

Adolescent↗

PubMed2005

Optimization of conditions for the efficient production of mutan in streptococcal cultures and post-culture liquids.

The strain Streptococcus sobrinus CCUG 21020 was found to produce water-insoluble and adhesive mutan. The factors influencing both stages of the mutan production, i.e. streptococcal cultures and glucan synthesis in post-culture supernatants were standardized. The application of optimized process parameters for mutan production on a larger scale made it possible to obtain approximately 2.2 g of water-insoluble glucan per 11 of culture supernate--this productivity was higher than the best reported in the literature. It was shown that some of the tested beet sugars might be successfully utilized as substitutes for pure sucrose in the process of mutan synthesis. Nuclear magnetic resonance analyses confirmed that the insoluble biopolymer synthesized by a mixture of crude glucosyltransferases was a mixed-linkage (1-->3), (1-->6)-alpha-D-glucan (the so-called mutan) with a greater proportion of 1,3 to 1,6 linkages.

Bacterial Physiological Phenomena↗

PubMed1992

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 of the colonies of mutans streptococci resembled those of Streptococcus sobrinus. The mean counts of the mutans streptococci and lactobacilli were 100-fold higher in plaque samples from children with rampant caries as compared with caries-free children. No difference could be found between the numbers of mutans streptococci in plaque overlaying cavities and that from adjacent sound enamel. In contrast, the counts of lactobacilli in plaque were approximately 100-fold higher from cavities than from sound surfaces. The levels of mutans streptococci in saliva were directly related to the presence of rampant caries. The results show that caries-free and caries-active breast-fed children, aged 1 to 2.5 years, harbour mutans streptococci and lactobacilli on their teeth. Rampant caries in these children can occur in the absence of nursing bottles or any other feeding abuse during weaning and in the presence of an aciduric plaque microflora, as has been reported for children with nursing bottle caries.

Breast Feeding↗

PubMed1991

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 and lactobacilli than persons from whom S. sobrinus was not isolated. The S. sobrinus carriers also had significantly lower stimulated saliva secretion rates than the non-carriers. 95% of the subjects had detectable levels of lactobacilli in saliva with 35% having greater than 10(5) cfu per ml saliva. When the subjects were divided into classes according to the number of intermaxillary contacts, i.e. the Eichner classification, the distribution of subjects with high and low salivary counts of cariogenic bacteria varied. Thus fewer subjects belonging to Eichner class A showed higher salivary numbers of mutans streptococci (14% had greater than 10(6) cfu/ml) as well as lactobacilli (21% had greater than 10(5) cfu/ml) than, for example, subjects belonging to Eichner class B (26% had greater than 10(6) cfu/ml of mutans streptococci, 35% had greater than 10(5) cfu/ml of lactobacilli). Subjects who carried a removable denture(s) had significantly higher salivary numbers of both mutans streptococci and lactobacilli than subjects without removable dentures.

Aged↗

PubMed2000

Glycine prevents the phenotypic expression of streptococcal glucan-binding lectin.

Glycine has been used extensively in bacterial cell surface research. Some researchers employ glycine in growth media so as to increase the transformability of streptococci during electroporation. Others have found that glycine, similar to wall antibiotics, 'weakens' peptidoglycan. It is now shown that when glycine is incorporated into the growth medium, Streptococcus sobrinus exhibits a diminished ability to aggregate with high molecular weight alpha-1,6-glucan. Growth of the bacteria in either a rich or a chemically defined medium results in a cell population with full lectin (glucan-binding) fidelity. Incorporation of glycine, but not serine or other amino acids, at concentrations of 100-200 mM gives rise to bacteria with lowered lectin activities. Bacteriolytic enzymes were able to lyse bacteria from glycine-grown cultures more readily than from cultures without the glycine supplement. The bacteria produce glucan-binding proteins, including glucosyltransferases, but they do not readily aggregate with added dextran. Furthermore, SDS-PAGE gels of supernatants of growth media (+/-glycine) are similar, suggesting the bacteria do not produce a unique set of proteins. Western blotting with a fluorescein isothiocyanate-labeled dextran probe reveals normal amounts of glucan-binding proteins in glycine-grown streptococci. Glycine may be acting as a type of antibiotic, reducing wall integrity upon which glucan promoted cellular aggregation depends.

Bacterial Proteins↗

PubMed2002

Similarity of the oral microbiota of pre-school children with that of their caregivers in a population-based study.

This study evaluated the similarity between the oral microbiota of young children and that of their adult caregivers. Oral samples from children (174 dentate and 18 pre-dentate) aged 6-36 months and their caregivers in Saipan were assayed using a DNA probe assay. Many species including Streptococcus mutans, Streptococcus sobrinus, Actinomyces species, Campylobacter rectus, Fusobacterium nucleatum, Prevotella intermedia, and Porphyromonas gingivalis were detected in dentate and pre-dentate children, whereas Bacteroides forsythus was detected only in dentate children. A higher percentage of children were positive for the detection of an individual species if the caregiver was also positive. There were significant relative risks of species detection between dentate children and their caregivers. By logistic regression, there were significant positive associations between species detection in caregiver and in child, but not between species detection and child age or maternal education level. In conclusion, dental pathogens were detected in young, including pre-dentate, children. The microbial profiles of children were strongly associated with the microbiota of their caregivers.

Actinomyces↗

PubMedDate not supplied

Synergistic inhibition by combination of fluoride and xylitol on glycolysis by mutans streptococci and its biochemical mechanism.

The purpose of this study was to evaluate the combined inhibitory effect of fluoride and xylitol on acid production by mutans streptococci, Streptococcus mutans NCTC10449 and Streptococcus sobrinus 6715, from glucose under strictly anaerobic conditions at fixed pH 5.5 and 7.0. The bacteria were grown in a tryptone-yeast extract broth under strictly anaerobic conditions (N2: 80%; H2: 10%; CO2: 10%). Reaction mixtures for acid production from glucose contained bacterial cells with fluoride (0-6.4 mM) and/or xylitol (60 mM). Acidic end products of glucose fermentation and intracellular glycolytic intermediates were assayed. The combination of fluoride and xylitol inhibited acid production more effectively than fluoride or xylitol alone. In the presence of fluoride and xylitol, the proportion of lactic acid in the total amount of acidic end products decreased, while the proportion of formic and acetic acids increased. Analyses of intracellular glycolytic intermediates revealed that xylitol inhibited the upper part of the glycolytic pathway, while fluoride inhibited the lower part. This study indicates that fluoride and xylitol together have synergistic inhibitory effects on the acid production of mutans streptococci and suggests that xylitol has the potential to enhance inhibitory effects of low concentrations of fluoride.

Cariostatic Agents↗

PubMed1997

Anti-bacterial action of onion (Allium cepa L.) extracts against oral pathogenic bacteria.

In this study, the focus was on the antibacterial activity of onions. This study researched the activities of onion extracts on Streptococcus mutans and Streptococcus sobrinus, the main causal bacteria for dental caries, and Porphyromonas gingivalis and Prevotella intermedia, considered to be the main causal bacteria of adult periodontitis. The results showed that the onion extracts possess an effect on all test bacterial strains (S.mutans JC-2, S. sobrinus OMZ176, P. gingivalis ATCC 33277 and P. intermedia ATCC 25611), and the effects were bactericidal against cultured and resting bacterial cells. The activity of the onion extracts was stable even after 48 hours in the culture medium. This result suggests that no decomposition or volatility of onion extracts occurred in the culture medium. The antibacterial activity of onion extracts was not markedly influenced by cysteine (10 mM) treatment. However, activity significantly decreased with alkali treatment. Grated onion left to stand at 37 degrees C for 48 hours did not show antibacterial activity. Also, activity of steam treated (100 degrees C, 10 min.) onion was not observed. Using avicel plate by thin layer chromatography with the solvent of n-butanol:acetic acid:water (3:3:1), the main component of the substance (the substance which develops color with ninhydrin) was observed at an Rf value of about 0.9.

1-Butanol↗