Distribution of biotypes and antimicrobial susceptibility of Actinobacillus actinomycetemcomitans

Eighty isolates of Actinobacillus actinomycetemcomitans from 30 Brazilian periodontitis patients were examined to determine the distribution of biotypes and in vitro antimicrobial susceptibility. Seventy-seven percent of the isolates belonged to biotype X. All A. actinomycetemcomitans isolates were susceptible to cefoxitin, imipenem and tetracycline.     

云南省鼠疫菌某些生物学特性及其流行病学意义

报告了分离自云南省的鼠疫菌质粒ＤＮＡ种类、毒力、毒力因子和生化特性。结合地理分布将其划分为剑川山区和滇西、南部平坝居民区两种生物型，其中后者还可分为Ａ、Ｂ两个亚型，各生物型有其特定的分布区城。本文还证实鼠疫菌６、４５和６５ＭＤ质粒与毒力相关，并介导着Ｐｓｔ、Ｖｗａ和Ｆｒａ的产生，但质粒与本研究所检测的１３种生化特性无关。通过质粒分析，从分子水平证实滇西南及滇南存在着黄胸鼠鼠疫疫源地。     

Candida biotypes in human adult periodontitis

Fifty-five Candida isolates from human periodontal pockets were biotyped using the API 20C micromethod kit system. Candida albicans (11 biotypes) constituted 81.8% of all yeast isolates. A single biotype accounted for 57.8% of the subgingival C. albicans strains. The biotype distribution of C. albicans in human periodontal pockets appears to follow a selectivity pattern similar to that of other oral surfaces.     

A new look at the mechanism of cholera endemicity caused by Vibrio cholerae biotype eltor

ＣｈｏｌｅｒａｃａｕｓｅｄｂｙＶｉｂｒｉｏｃｈｏｌｅｒａｅｂｉｏｔｙｐｅｅｌｔｏｒ (ＥＶＣ)ｏｒｉｇｉｎａｔｅｄｉｎ 1961ｉｎＣｅｌｅｂｅｓ ,ｓｐｒｅａｄｆａｒａｎｄｗｉｄｅａｌｌｏｖｅｒｔｈｅｗｏｒｌｄｔｏｆｏｒｍｔｈｅ 7ｔｈｐａｎｄｅｍｉｃｏｆｃｈｏｌｅｒａ ＷｉｔｈｔｈｅａｐｐｅａｒａｎｃｅｏｆＶ ｃｈｏｌｅｒａｅＯ139ｉｎ 1992ｉｎＭａｄｒａｓ,ｔｈｅ 8ｔｈｐａｎｄｅｍｉｃｗａｓｅｘｐｅｃｔｅｄ ,ｓｉｎｃｅｔｈｅｐｒｉｏｒｉｍｍｕｎｉｔｙｔｏＥＶＣｗａｓｎｏｔｐｒｏｔｅｃｔｉｖｅａｇａｉｎｓｔ…     

Assessment of genetic relatedness of vaginal isolates of Candida albicans from different geographical origins

PCR fingerprinting with single non-specific primers was used to type vaginal isolates of C. albicans from Portugal, Angola, Madagascar, and two regions of Germany (Berlin and Munich). In addition to analysing isolates that exhibited the normal biotype of C. albicans, the study included atypical strains that failed to assimilate glucosamine and N-acetylglucosamine, which were isolated from women in Angola and Madagascar. A total of 212 strains of C. albicans were studied, representing 87 different multi-locus genotypes. The genotypes of strains from each geographical population were highly similar but not identical. There was one exception: a strain from Portugal grouped with the typical strains from Angola. The typical and especially the atypical populations from Africa displayed less genotype variation than the populations from Europe. The Portuguese samples exhibited the greatest genotypic heterogeneity. Distance analysis (UPGMA) revealed a statistically weak correlation between genotype and geographical origin of the C. albicans isolates.     

Sample, count, identify, and store the mutans streptococci

Abstract – According to a new method for sampling mutans streptococci, "Strip mutans", a plastic strip is contaminated by human saliva and incubated in a selective broth. After growth the strip with adherent colonies may be dried and stored. We wanted to know for how long a time bacteria in the colonies were viable if the strips, were stored under different conditions. The survival time is important if the bacteria need to be subjected to further analyses. The results showed that the viability of the bacteria after the incubation period was at least l yr when the strips were stored frozen or frozen in glycerine. Stored dried in room temperature the survival was about 8 wk. A second part of the study aimed at identifying the colonies on strips obtained from different countries. Dried strips were sent air mail to our laboratory for biochemical and immunological analyses and the results showed that serotype/biotype c/e/f of S. mutans were most frequent but d/g S. sobrinus was also present in the samples, which came from Brazil, Greece, and Sweden. Three colonies of 213 on these strips did not grow, possibly indicating non-mutans bacteria.