Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to evaluate the consistency of the prevalence of mutans streptococci in a group of Swedish families. Eleven families, which had previously been examined for genotypes of mutans streptococci, were re-examined after 2-5 years. The families consisted of mother, father and a child (mean age 7.2 years at the follow-up examination). One father did not participate. Pooled plaque samples were obtained from buccal and occlusal surfaces. Isolates of mutans streptococci were genotyped using chromosomal DNA digested with restriction endonuclease HaeIII, separated by gel electrophoresis and visualised through UV illumination after ethidium bromide staining. Comparing the DNA fingerprints of mutans streptococci found at baseline and follow-up, 9 children harboured one or two genotypes which were similar on the two sampling occasions. Two of these children had also gained a genotype. The remaining 2 children had lost a genotype each and 1 of them had gained two new genotypes. All 21 adults showed one or two genotypes identical to those found at baseline. Nine of these 21 adults had also lost one genotype. Four of these 9 and additionally 4 of the remaining adults showed one or two new genotypes. Six mother-child pairs shared a genotype at baseline and this pattern remained for five pairs at the end of the study. The results suggest that genotypes of mutans streptococci have a fairly high degree of consistency in children between 3 and 8 years of age as well as in adults, indicating persistence of the strains. However, the results also indicate that some subjects may gain and/or lose genotypes.
Caries Res
PMID:Genotypes of mutans streptococci tend to persist in their host for several years. 1077 30

The purpose of this study was to investigate whether there was transmission between adults in Chinese families using chromosomal DNA fingerprinting. Plaque samples were obtained from buccal and occlusal surfaces of 11 married couples. The colonization levels of mutans streptococci were estimated as colony-forming units per milliliter, and caries experience was scored by decayed, missing and filled teeth. Information about medical history, diet regimes and age at marriage was obtained. The isolates were serotyped by biochemical test and genotyped using the restriction endonuclease HaeIII. The procedure was repeated after 3 months. The results showed that 1 couple had the same genotype of mutans streptococcus at the first examination, but this could not be repeated for the husband who had lost his mutans streptococci at the second examination. On the contrary, another couple that did not have the same mutans streptococcal genotype at the beginning had the same genotype after 3 months. No matching of genotypes was observed within 8 couples. In 1 male, no mutans streptococci were detected, therefore that couple was not considered. These data indicate that spouses had a chance to be infected by strains of mutans streptococci from another person. The results suggest that there may be transmission between adults in Chinese families, but it may be difficult for mutans streptococci to colonize another mouth permanently.
Caries Res
PMID:Transmission of mutans streptococci in adults within a Chinese population. 1206 67

The aim of the study was to examine the persistence of oral Streptococcus mutans in nasopharyngeal carcinoma patients after radiotherapy. Ten subjects, ranging in age from 20 to 67 years, participated. DMFT/DMFS, salivary level of mutans streptococci and oral health status were recorded. Pooled plaque samples were obtained from the cervical margins and the interproximal regions of all the teeth and the occlusal surfaces of the molars prior to, immediately after, 3 and 6 months after the completion of radiotherapy. At least 10 colonies of S. mutans were isolated from each subject and totally 645 isolates were genotyped by restriction endonuclease analysis. The results showed that the salivary level of S. mutans increased significantly with the reduction of salivary flow rate after radiotherapy. Each subject had at least 1 genotype of S. mutans isolated throughout the follow-up period. In 3 subjects who initially carried 2 or more genotypes, 1 or 2 genotypes of S. mutans could not be detected 3 months after treatment. Moreover, the genotypes that became undetectable were predominant bacteria in the first sampling. The result indicated that most S. mutans genotypes were persistent after radiotherapy but some genotypes that might not adapt to the alteration of oral environment became undetectable.
Caries Res
PMID:The persistence of Streptococcus mutans in nasopharyngeal carcinoma patients after radiotherapy. 1625 93