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Dispersal is a key component of a species' life history, by influencing population persistence, genetic structure, adaptation and maintenance of genetic diversity. The Asiatic toad (Bufo gargarizans) is a widespread species in east Asia. However, we still have no knowledge of what kind of geographical scale equates to genetic differentiation within B. gargarizans. In this study, the population genetics of B. gargarizans was studied at five localities, with the Yangtze River running through the sampling area, in order to detect the level of genetic differentiation and the natural barriers to the species' dispersal on a small geographic scale, by means of the development and use of novel microsatellite loci. These markers revealed a relatively high level of genetic diversity. Distinct genetic structure among populations in B. gargarizans was observed, as described by genetic distance, AMOVA, PCA and Geneland results. A weak but significant positive correlation between genetic distance and geographical distance. The combination of these findings suggests that the Yangtze River and geographic distance may act as effective barriers for B. gargarizans. These results serve as benchmark data for understanding the impacts of dispersal barriers and continued landscape research on B. gargarizans. In this study, the population genetics of Bufo gargarizans were studied in five localities with the Yangtze River running through the sampling area to draw inference about the genetic differentiation level and natural barriers to species dispersal in small geographic scale with landscape features using novel microsatellite loci. Significant genetic structure and weak but significant positive correlation between genetic and geographical distances were found, which indicates that the Yangtze River and geographic distance may act as an effective barrier for B. gargarizans. [ABSTRACT FROM AUTHOR]

Assessment of organ damage has become the standard outcome measure for morbidity and mortality in patients with lupus. Ethnicity is thought to be a marker for genetic, environmental, behavioral, and other variables that may affect disease outcomes. Previous studies suggest that Asians residing in western countries had significantly higher prevalence of damage compared with Whites. In contrast, studies performed in Chinese, Korean and Arab patients showed that the overall prevalence of damage and the most commonly involved organs (neuropsychiatric and musculoskeletal) were similar to Whites. Compared with their Asian counterparts, Pakistani and Jewish patients appeared to have a higher prevalence of damage, most likely secondary to longer disease duration. Chinese patients had an increased prevalence of premature gonadal failure, whereas patients residing in western and southern Asia had more skin damage. When compared with Whites, Asian patients had more renal damage but less ocular and cardiovascular damage. Risk factors associated with organ damage in Asian lupus patients included older age, higher disease activity, and the use of cyclophosphamide and steroids. Further investigations into other determinants such as genetic predisposition, socioeconomic factors, prevalence and severity of disease manifestations, and treatment, is needed in order to understand the variation in damage accrual in lupus patients from different ethnicities.