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991.
We analyzed highly vancomycin-resistant Gram-positive bacteria isolated from the saliva of migratory songbirds captured, sampled, and released from a bird-banding station in western Kansas. Individual bacterial isolates were identified by partial 16S rRNA sequencing. Most of the bacteria in this study were shown to be Staphylococcus succinus with the majority being isolated from the American Robin. Some of these bacteria were shown to carry vanA, vanB, and vanC vancomycin-resistance genes and have the ability to form biofilms. One of the van gene-carrying isolates is also coagulase positive, which is normally considered a virulence factor. Other organisms isolated included Staphylococcus saprophyticus as well as Enterococcus gallinarum. Given the wide range of the American Robin and ease of horizontal gene transfer between Gram-positive cocci, we postulate that these organisms could serve as a reservoir of vancomycin-resistance genes capable of transferring to human pathogens.  相似文献   
992.
Mapping of human chromosome 22 with a panel of somatic cell hybrids   总被引:7,自引:0,他引:7  
The adenylosuccinate lyase (ADSL) which is essential for generating adenylate, maps to the long arm of chromosome 22. By using a Chinese hamster ovary cell line deficient in ADSL activity, we have constructed a set of 17 somatic cell hybrids containing defined regions of human chromosome 22. This panel was extended with six additional hybrids, obtained in other laboratories using various methods of selection. Southern analysis of the hybrids with 38 chromosome 22 probes defined 14 different subregions which could be linearly organized on the long arm of chromosome 22. The order of the probes thus deduced is fully compatible with their previous localization and with the genetic map. The ADSL gene was further sublocalized between the MB and D22S22. This panel, which enables the rapid assignment of chromosome 22 single copy probes to small subregions, will be an important tool in the construction of a detailed physical map of this part of the genome.  相似文献   
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Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654) in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC) is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples’ culture and lifestyles.  相似文献   
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