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Global climate change is expected to have a profound effect on species distribution. Due to the temperature constraints, some narrow niche species could shift their narrow range to higher altitudes or latitudes. In this study, we explored the correlation between species traits, genetic structure, and geographical range size. More specifically, we analyzed how these variables are affected by differences in fundamental niche breadth or dispersal ability in the members of two sympatrically distributed stream‐dwelling amphibian species (frog, Quasipaa yei; salamander, Pachyhynobius shangchengensis), in Dabie Mountains, East China. Both species showed relatively high genetic diversity in most geographical populations and similar genetic diversity patterns (JTX, low; BYM, high) correlation with habitat changes and population demography. Multiple clustering analyses were used to disclose differentiation among the geographical populations of these two amphibian species. Q. yei disclosed the relatively shallow genetic differentiation, while P. shangchengensis showed an opposite pattern. Under different historical climatic conditions, all ecological niche modeling disclosed a larger suitable habitat area for Q. yei than for P. shangchengensis; these results indicated a wider environment tolerance or wider niche width of Q. yei than P. shangchengensis. Our findings suggest that the synergistic effects of environmental niche variation and dispersal ability may help shape genetic structure across geographical topology, particularly for species with extremely narrow distribution. [ABSTRACT FROM AUTHOR]

The Chinese alligator (Alligator sinensis) is currently an endangered species due to a combination of factors, including climate change, anthropogenic activities, and habitat fragmentation. Captivity plays a crucial role in mitigating the decline of the Chinese alligator population. Currently, there is a lack of clarity regarding the influence of host development and captive conditions on the gut microbiota of Chinese alligators. The aim of the study was to investigate the gut bacterial communities of Chinese alligators and their surrounding environmental bacterial communities using 16S rRNA sequencing. The primary gut flora of Chinese alligators consists of Proteobacteria, Bacteroidetes, and Firmicutes. Proteobacteria is the most abundant and efficient settler in the gut, water, and sediment. PCoA and Adonis test revealed significant differences in bacterial communities across these habitats. Venn analysis revealed overlap in OTUs among the gut, water, and sediment, varying with growth stage and density stress. Different growth stages of Chinese alligator guts harbor distinct pathogenic bacteria, requiring attention. Density stress leads to an increase in pathogenic bacteria, a decrease in gut absorption efficiency. PICRUst2 predicts more abundant metabolic pathways related to gut function during high‐density stress, possibly linked to Roseburia. SourceTracker Analysis indicated that water bacteria have a greater impact on Chinese alligator gut bacteria than sediment, and density stress significantly affects the contribution of environmental microorganisms to the gut microbes of Chinese alligator. BugBase analysis identified water body microbes as the main source of "potentially pathogenic" phenotypes in the gut microbiota. RDA analysis found dissolved oxygen (DO) in water to be the most significant factor influencing water microorganisms, positively correlated with certain pathogenic strains. These findings enhance our understanding of the significance of microbial communities in the gut and surrounding aquatic environment of the Chinese alligator. Furthermore, they provide theoretical support for environmental regulation, disease control, and healthy breeding. [ABSTRACT FROM AUTHOR]

Amphibians and reptiles, especially the critically endangered Chinese alligators, are vulnerable to climate change. Historically, the decline in suitable habitats and fragmentation has restricted the distribution of Chinese alligators to a small area in southeast Anhui Province in China. However, the effects of climate change on range‐restricted Chinese alligator habitats are largely unknown. We aimed to predict current and future (2050s and 2070s) Chinese alligator distribution and identify priority conservation areas under climate change. We employed species distribution models, barycenter migration analyses, and the Marxian model to assess current and future Chinese alligator distribution and identify priority conservation areas under climate change. The results showed that the lowest temperature and rainfall seasonality in the coldest month were the two most important factors affecting the distribution of Chinese alligators. Future predictions indicate a reduction (3.39%–98.41%) in suitable habitats and a westward shift in their distribution. Further, the study emphasizes that suitable habitats for Chinese alligators are threatened by climate change. Despite the impact of the Anhui Chinese Alligator National Nature Reserve, protection gaps persist, with 78.27% of the area lacking priority protected area. Our study provides crucial data for Chinese alligator adaptation to climate change and underscores the need for improved conservation strategies. Future research should refine conservation efforts, consider individual plasticity, and address identified limitations to enhance the resilience of Chinese alligator populations in the face of ongoing climate change. [ABSTRACT FROM AUTHOR]

Aim: To determine the associations between the Chinese visceral adiposity index (CVAI) and the risks of all‐cause and cause‐specific mortality. Materials and Methods: A total of 3 916 214 Chinese adults were enrolled in a nationwide population cohort covering all 31 provinces of mainland China. The CVAI was calculated based on age, body mass index, waist circumference, and triglyceride and high‐density lipoprotein cholesterol concentrations. We used a Cox proportional hazards regression model to determine the hazard ratios and 95% confidence intervals (CIs) for risk of mortality associated with different CVAI levels. Results: The median follow‐up duration was 3.8 years. A total of 86 158 deaths (34 867 cardiovascular disease [CVD] deaths, 29 884 cancer deaths, and 21 407 deaths due to other causes) were identified. In general, after adjusting for potential confounding factors, a U‐shaped relationship between CVAI and all‐cause mortality was observed by restricted cubic spline (RCS). Compared with participants in CVAI quartile 1, those in CVAI quartile 4 had a 23.0% (95% CI 20.0%–25.0%) lower risk of cancer death, but a 23.0% (95% CI 19.0–27.0) higher risk of CVD death. In subgroup analysis, a J‐shaped and inverted U‐shaped relationship for all‐cause mortality and cancer mortality was observed in the group aged < 60 years. Conclusions: The CVAI, an accessible indicator reflecting visceral obesity among Chinese adults, has predictive value for all‐cause, CVD, and cancer mortality risks. Moreover, the CVAI carries significance in the field of health economics and secondary prevention. In the future, it could be used for early screening purposes. [ABSTRACT FROM AUTHOR]

Pathogenic variation in BRCA1 and BRCA2 (BRCA) causes high risk of breast and ovarian cancer, and BRCA variation data are important markers for BRCA‐related clinical cancer applications. However, comprehensive BRCA variation data are lacking from the Asian population despite its large population size, heterogenous genetic background and diversified living environment across the Asia continent. We performed a systematic study on BRCA variation in Asian population including extensive data mining, standardization, annotation and characterization. We identified 7587 BRCA variants from 685 592 Asian individuals in 40 Asia countries and regions, including 1762 clinically actionable pathogenic variants and 4915 functionally unknown variants (https://genemutation.fhs.um.edu.mo/Asian-BRCA/). We observed the highly ethnic‐specific nature of Asian BRCA variants between Asian and non‐Asian populations and within Asian populations, highlighting that the current European descendant population‐based BRCA data is inadequate to reflect BRCA variation in the Asian population. We also provided archeological evidence for the evolutionary origin and arising time of Asian BRCA variation. We further provided structural‐based evidence for the deleterious variants enriched within the functionally unknown Asian BRCA variants. The data from our study provide a current view of BRCA variation in the Asian population and a rich resource to guide clinical applications of BRCA‐related cancer for the Asian population. [ABSTRACT FROM AUTHOR]

The Chinese alligator is an endemic crocodilian species in China. We isolated and obtained the glucocorticoid and mineralocorticoid receptor genes coding from the kidney of Alligator sinensis by nested polymerase chain reaction (PCR) and rapid amplification of cDNA ends (RACE). The glucocorticoid receptor (GR) gene has 2343 base pairs encoding 780 amino acids, while the mineralocorticoid receptor (MR) gene is 2958 bp in length encoding 985 amino acids. Quantitative real‐time PCR was used to detect the distribution of messenger RNA (mRNA) levels. The maximum mRNA expressions were observed in the ovary and kidney, suggesting that these receptors may be involved in basic cellular functions or stress response of alligators. Besides this, RT‐qPCR was performed to analyze the abundance of GR and MR mRNA transcripts in early embryonic development of the Chinese alligator in the kidney, liver, and heart. The mRNA levels of GR and MR at earlier stages in kidney, liver, and heart indicates that they might involve in the transcriptional regulation of early embryos and activate many precise developmental effects in fetal tissues. We also measured the protein expression in the liver embryonic developmental stages and found that the GR and MR proteins were restricted to both the nuclei and cytoplasm. The protein expression levels in the liver at different embryonic developmental stages have extremely prominent differences. Taken together, our results showed the full coding regions of GR and MR, their characteristics, and embryonic developmental mRNA and protein expressions of both genes in A. sinensis. This study could provide the necessary information for further investigating the diverse functions of GR and MR in A. sinensis. [ABSTRACT FROM AUTHOR]

Hibernation is a physiological state for Chinese alligators to cope with cold weather. In mammals, gene expression changes during hibernation and their regulatory mechanisms have been extensively studied, however, these studies in reptiles are still rare. Here, integrated analysis of messenger RNA (mRNA), microRNA (miRNA), and long noncoding RNA (lncRNA) reveals the molecular mechanisms of the hypothalamus, liver, and skeletal muscle in hibernating and active individuals. During hibernation, the number of genes increased in the hypothalamus, liver, and skeletal muscle was 585, 282, and 297, while the number of genes decreased was 215, 561, and 627, respectively, as compared with active individuals. Through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis, the differential expressed genes were mainly enriched in DNA damage repair, biological rhythm, energy metabolism, myoprotein degradation, and other related items and pathways. Besides, 4740 miRNAs were identified in three tissues. Through the comprehensive analysis of miRNA and mRNA abundance profiles, 12,291, 6997, and 8232 miRNA–mRNA pairs all showed a negative correlation in the hypothalamus, liver, and skeletal muscle, respectively. Some miRNA target genes were related tobiological rhythm and energy metabolism, suggesting that miRNA may play an important role in the physiological metabolism of the hibernating adaptability of Chinese alligators. Moreover, 402, 230, and 130 differentially expressed lncRNAs were identified in the hypothalamus, liver, and skeletal muscle, respectively. The targeting relationship of four lncRNA–mRNA pairs were predicted, with the main function of target genes involved in the amino acid transportation. These results are helpful to further understand the molecular regulatory basis of the hibernation adaptation in Chinese alligators. Highlights: Some candidate genes related to hibernation physiology were identifiedmiRNA and lncRNA of Alligator sinensis were identifiedmiRNAs could play a key role in the regulation of gene expression in Chinese alligator during hibernation [ABSTRACT FROM AUTHOR]

BRCA1 and BRCA2 play essential roles in maintaining the genome stability. Pathogenic germline mutations in these two genes disrupt their function, lead to genome instability and increase the risk of developing breast and ovarian cancers. BRCA mutations have been extensively screened in Caucasian populations, and the resulting information are used globally as the standard reference in clinical diagnosis, treatment and prevention of BRCA‐related cancers. Recent studies suggest that BRCA mutations can be ethnic‐specific, raising the question whether a Caucasian‐based BRCA mutation information can be used as a universal standard worldwide, or whether an ethnicity‐based BRCA mutation information system need to be developed for the corresponding ethnic populations. In this study, we used Chinese population as a model to test ethnicity‐specific BRCA mutations considering that China has one of the latest numbers of breast cancer patients therefore BRCA mutation carriers. Through comprehensive data mining, standardization and annotation, we collected 1,088 distinct BRCA variants derived from over 30,000 Chinese individuals, one of the largest BRCA data set from a non‐Caucasian population covering nearly all known BRCA variants in the Chinese population (https://dbBRCA-Chinese.fhs.umac.mo). Using this data, we performed multi‐layered analyses to determine the similarities and differences of BRCA variation between Chinese and non‐Chinese ethnic populations. The results show the substantial differences of BRCA data between Chinese and non‐Chinese ethnicities. Our study indicates that the current Caucasian population‐based BRCA data is not adequate to represent the BRCA status in non‐Caucasian populations. Therefore, ethnic‐based BRCA standards need to be established to serve for the non‐Caucasian populations. What's new? Currently, Caucasian population‐based BRCA mutation data are used worldwide as the standard reference for diagnosis, treatment, and prevention of BRCA‐associated cancers. Recent studies however suggest that BRCA variation can be ethnic specific. Here, the authors carried out a comprehensive comparison of BRCA mutation data between the Chinese and worldwide non‐Chinese populations and found substantial differences. The study suggests that BRCA mutations are highly ethnic specific and that the current Caucasian population‐based BRCA data is not adequate to represent the BRCA status in non‐Caucasian populations. Developing new standard references using ethnic‐based BRCA mutation data is needed to better serve non‐Caucasian ethnic populations. [ABSTRACT FROM AUTHOR]

A protease inhibitor, cystatin C (Cst C), is a secreted cysteine protease inhibitor abundantly expressed in body fluids. Clinically, it is mostly used to measure glomerular filtration rate as a marker for kidney function due to its relatively small molecular weight and easy detection. However, recent findings suggest that Cst C is regulated at both transcriptional and post-translational levels, and Cst C production from haematopoietic cell lineages contributes significantly to the systematic pools of Cst C. Furthermore, Cst C is directly linked to many pathologic processes through various mechanisms. Thus fluctuation of Cst C levels might have serious clinical implications rather than a mere reflection of kidney functions. Here, we summarize the pathophysiological roles of Cst C dependent and independent on its inhibition of proteases, outline its change of expression by various stimuli, and elucidate the regulatory mechanisms to control this disease-related protease inhibitor. Finally, we discuss the clinical implications of these findings for translational gains. [ABSTRACT FROM AUTHOR]

Anomalies of the biliary system are not uncommon, these may involve the biliary ducts or the gallbladder (GB). Some of the reported variations of the GB include its agenesis, duplication, floating GB with a mesentery and intrahepatic GB. Type-II anomaly, which is the most common, is defined as two separate GBs, each with its own cystic duct draining independently into the common bile duct (H-type) or with one of the cystic ducts draining into the right or left hepatic duct (trabecular type). [Extracted from the article]

A number of anatomical variations of the gallbladder have been reported[[1], [3]] including gallbladder duplication, a congenital biliary anomaly with an incidence of 1 in 4000.[5] Anatomical variations of the gallbladder are of particular significance to the surgeon as they can make dissection in the cystohepatic triangle challenging, which may lead to injuries of the extrahepatic bile ducts. We proceeded with retrograde dissection of the gallbladder from the liver bed. However, a gallbladder passing through the liver has not been reported previously in an English language journal and we have termed this striking variant a transhepatic gallbladder. [Extracted from the article]

The Chinese alligator ( Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese alligator are on the edge of extinction. Through a release program, some captive-bred alligators will be selected and released into the wild to supplement and renew natural populations. The purpose of this study was to investigate the genetic variation of captive-bred Chinese alligators by AFLP markers and to select individuals with maximally different genetic backgrounds for release. Forty-three captive-bred alligators of the second filial generation from the Anhui Research Center for Chinese Alligator Reproduction (ARCCAR) were surveyed using four primer combinations, yielding 117 AFLP markers. According to AFLP fingerprints, six samples had distinctly different band patterns compared to other samples. When the six samples were removed from the analysis, there were 19 monomorphic loci and 98 polymorphic loci yielding 84% polymorphic loci. Moreover, the genetic similarity (GS) among 37 samples varied from 0.13-0.97, and the average was 0.7503±0.0064 standard error (SE). When the six samples were included, the GS value among the 43 samples declined and varied from 0.06-0.97, and the average was 0.6523±0.0079 SE. Based on a cluster analysis using UPGMA, a dendrogram of the 43 alligators was constructed. According to the cluster analysis and gender of the 43 samples, eight Chinese alligators with very different genetic backgrounds were selected and suggested for release with two groups in the future. Zoo Biol 0:1-12, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]