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Prabodh K. Bajpai Ashish R. Warghat Ram Kumar Sharma Ashish Yadav Anil K. Thakur Ravi B. Srivastava Tsering Stobdan 《Biochemical genetics》2014,52(3-4):137-152
Sequence-related amplified polymorphism markers were used to assess the genetic structure in three natural populations of Morus alba from trans-Himalaya. Multilocation sampling was conducted across 14 collection sites. The overall genetic diversity estimates were high: percentage polymorphic loci 89.66%, Nei’s gene diversity 0.2286, and Shannon’s information index 0.2175. At a regional level, partitioning of variability assessed using analysis of molecular variance (AMOVA), revealed 80% variation within and 20% among collection sites. Pattern appeared in STRUCTURE, BARRIER, and AMOVA, clearly demonstrating gene flow between the Indus and Suru populations and a geographic barrier between the Indus-Suru and Nubra populations, which effectively hinders gene flow. The results showed significant genetic differentiation, population structure, high to restricted gene flow, and high genetic diversity. The assumption that samples collected from the three valleys represent three different populations does not hold true. The fragmentation present in trans-Himalaya was more natural and less anthropogenic. 相似文献
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The role of G-protein activation in cardiovascular disorders is well-known. G-protein β3 subunit (GNB3) C825T polymorphism is associated with increased intracellular signal transduction. We investigated the role of the variant in plasma sodium and potassium concentrations and association with hypertension. 345 healthy controls and 455 patients with essential hypertension were enrolled. Plasma renin activity and aldosterone concentration were measured. The variant, typed by SNaPshot, was analyzed on an ABI Prism 3100 Genetic Analyzer and GeneScan. The TT genotype and T allele were over-represented in the patients (p < 0.001, p < 0.0001). Multiple-logistic regression disclosed that the risk of hypertension was significantly greater for TT (p < 0.0001, OR = 6.1, CI = 2.9-12.7). One-way ANOVA revealed that hypertensive T-allele carriers (CT+TT), compared to non-carriers (CC), had a greater body mass index (BMI), mean arterial pressure (MAP) and PAC (p = 0.01, p = 0.01, p < 0.0001, respectively); while the patients with 825TT risk genotype showed higher plasma sodium and lower potassium (p < 0.0001, each). The results strongly emphasize, not only the role of C825T polymorphism by the induction of increased G-protein activity and enhancement of Na/h exchangers, but also the association with higher plasma sodium and lower potassium levels, high BMI and susceptibility to hypertension. 相似文献
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Sylvia Hofmann Sabine Kraus Tsering Dorge Michael Nothnagel Georg Miehe 《Journal of Biogeography》2014,41(11):2162-2172
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西藏阿里故如甲木墓地位于阿里地区噶尔县,是迄今为止阿里地区发现的规模最大、埋葬最集中的古代墓葬群。2012-2014年由中国社会科学院考古研究所和西藏自治区文物保护研究所联合开展发掘工作,发现并清理了11座墓葬,其中8座墓葬的时代略早,约为公元3-4世纪。另外3座为公元7-9世纪的吐蕃时期墓葬。本文对时代略早的8座故如甲木墓地出土的人骨进行了牙齿磨耗的观察,计算了每颗牙齿的平均磨耗等级以及前后部牙齿的磨耗差别指数,并选择了7组不同时代、不同地点、不同生业类型的古代人群进行了比较分析。结果表明,故如甲木的古代人群牙齿磨耗与畜牧业人群的磨耗接近,这也符合故如甲木当时的生业类型,即以牧业为主,辅以青稞和谷物的种植栽培。从牙齿磨耗推测故如甲木的人群在食物结构中有足够的动物性食物,这与碳氮同位素的食物结构分析结果也是一致的。 相似文献
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Rajput C Arif E Vibhuti A Stobdan T Khan AP Norboo T Afrin F Qadar Pasha MA 《Biochemical and biophysical research communications》2006,348(2):735-740
Sojourners visiting high-altitude (HA) (>2500 m) are susceptible to HA disorders; on the contrary, HA natives are well adapted to the extreme hypoxic environment. High aldosterone levels are believed to be involved in HA disorders, we, therefore, envisaged role of CYP11B2 gene variants in HA adaptation and therefore investigated the -344T/C, intron-2 conversion (Iw/Ic), K173R, and A5160C polymorphisms. In addition, polymorphisms in AGT, AT1R, ATP1A1, ADRB2, and GSTP1 genes were also investigated. The study comprised of 662 subjects, comprising of 426 Himalayan highlanders (HLs) and 236 lowlanders (LLs). The -344T/C and K173R polymorphisms were found to be in complete linkage disequilibrium. The wild-type allele -344T and combination of wild-type homozygous genotypes between -344T/C, Iw/Ic, and A5160C polymorphisms, containing all the six wild-type alleles were over-represented in the HLs (p < 0.0001, and p = 0.008, respectively). The wild-type haplotypes -344T-Iw, -344T-5160A, and -344T-Iw-5160A also showed over-representation in the HLs (p < 0.0001). Furthermore, greater the number of wild-type alleles, lower was the ARR (p < 0.05). The genotype distribution in remaining genes did not differ. To conclude, the over-representation of wild-type -344T allele, genotype combinations and haplotypes of CYP11B2, and their correlation with lower aldosterone levels associate with HA adaptation in the HLs. Such an allelic presentation in sojourners may help them cope with adverse HA environment. 相似文献
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? Premise of the study: Microsatellite markers were developed in an alpine plant endemic to the Qinghai-Tibetan Plateau, Androsace tapete, to investigate its spatial genetic structure, gene flow, and mating patterns. ? Methods and Results: Using the combined biotin capture method, 16 microsatellite primer sets were isolated and characterized. Fifteen of these markers showed polymorphism, and the number of alleles per locus ranged from three to 13 across 56 individuals from six Tibetan populations. ? Conclusions: These markers provide a useful tool to investigate the spatial genetic structure, gene flow, and mating system of A. tapete. 相似文献
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First investigation of ultraoligotrophic alpine Lake Puma Yumco in the pre-Himalayas,China 总被引:3,自引:0,他引:3
Osamu?MitamuraEmail author Yasushi?Seike Kunio?Kondo Naoshige?Goto Kaori?Anbutsu Tetsuji?Akatsuka Masaki?Kihira Tsering Qung?Tsering Mitsugu?Nishimura 《Limnology》2003,4(3):167-175
Lake Puma Yumco is a typical alpine lake (altitude 5030m) located in the pre-Himalayas of Tibet, China, and this study was the first limnological investigation ever conducted on it. Lake Puma Yumco (28°34N, 90°24E) has the following morphometric properties: maximum length 31km, maximum width 14km, mean width 9km, shoreline 90km, surface area 280km2, and shoreline development 1.5. Transparency was approximately 10m, even in the thawing season. The extinction coefficient of the lake water was calculated as 0.15m–1. Annual maximum transparency was estimated from the depth of the Chara zone to be 30m. Dissolved oxygen was 7mg O2 l–1 and showed saturated values, and salinity was 360mgl–1. The chemical type of the lake water was Mg-Ca-HCO3-SO4, and it was slightly alkaline in character. Total nitrogenous nutrients (sum of ammonia, nitrite, nitrate, and urea nitrogen), phosphate, and silicate were extremely low at 1, 0.02, and 9µM, respectively. Dissolved organic carbon, nitrogen, and phosphorus concentrations were 160, 11, and 0.08µM and the molar ratio was calculated as 2100:140:1. Chlorophyll a concentration was 0.2mgm–3. Phytoplankton and zooplankton were dominated by Aphanocapsa sp. and Diaptomidae. Both nitrogen and phosphorus appear to be the limiting parameters for phytoplankton growth. Organic carbon and nitrogen contents in lake sediments were low and the sediments contained a large amount of CaCO3. The grain size of sediment was that of silt-sand in most cases. The present results indicate that the pre-Himalayan alpine freshwater Lake Puma Yumco is an ultraoligotrophic lake. 相似文献
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Helix-helix parallel interfaces can be characterized by certain combinations of amino acids, which repeatedly occur at core positions a and d (leucine zipper nomenclature) in homologous and nonhomologous proteins and influence interhelical angles. Applied for the prediction of interhelical angles in glutathione S-transferase, intracellular chloride channel and annexin molecules from various sources, correct results were achieved in 58 out of 62 proteins. Interhelical angles are found to correlate with the conformation of the glutathione S-transferase ligands glutathione, s-hexylglutathione, glutathione sulfonic acid, and glutathione-s-dinitrobenzene. 相似文献