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藏鸡心脏高海拔低氧适应相关酶的研究 总被引:2,自引:0,他引:2
目的:研究藏鸡心脏对高海拔低氧适应性的生理特征。方法:本研究将藏鸡、矮小隐性白和寿光鸡分别饲养在低海拔和高海拔环境,测定10周龄时心脏重量、心肌乳酸(LA)和乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)活性。结果:结果显示藏鸡在高海拔环境中,心脏相对重量未明显增加,心肌LA低于对照鸡,LDH与对照鸡差异不显著,而SDH活性明显高于对照鸡。结论:结果说明了藏鸡对高海拔低氧环境的适应,不是通过增加心脏器官的重量,也不是通过提高无氧代谢的水平,较高的SDH活力对藏鸡心肌低氧适应有一定的意义。SDH是藏鸡适应低氧的一种标志酶。 相似文献
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牧草外生菌根菌黄绿卷毛菇Floccularia luteovirens具有较高的生态和经济价值,其生境微生物对其菌丝生长、菌根化和子实体形成具有促进作用。本研究利用高通量测序技术对西藏黄绿卷毛菇菌窝土壤及其周围无菇土壤微生物群落组成进行分析,挖掘促进黄绿卷毛菇生长的有益微生物资源。结果显示,西藏黄绿卷毛菇生境土壤细菌隶属于17门22纲116目161科227属,其中酸杆菌门、变形菌门、拟杆菌门和疣微菌门累计比例高达81.75%;生境土壤真菌隶属于5门17纲34目55科61属,子囊菌门和担子菌门累计比例高达80.89%。对比周围无菇土壤的微生物群落,促进黄绿卷毛菇生长的潜在细菌类群为Flavisolibacter、黄杆菌属Flavobacterium、芽单胞菌属Gemmatimonas、Haliangium、赛格特杆菌Segetibacter和鞘氨醇单胞菌属Sphingomonas;促进黄绿卷毛菇生长的潜在真菌类群为斜盖伞属Clitopilus、丝膜菌属Cortinarius、被孢霉属Mortierella和毛霉属Mucor。土壤微生物促进黄绿卷毛菇生长繁殖的机制有待进一步研究。 相似文献
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Jarvis RM Chamba A Holder MJ Challa A Smith DC Hodgkin MN Lord JM Gordon J 《Biochemical and biophysical research communications》2007,355(4):944-949
The centroblast-specific differentiation marker CD77 (Gb(3)), is the receptor for Shiga-like toxin (SLT). The dynamic relationship between Gb(3)/CD77 and key B-cell membrane proteins was studied in Burkitt's lymphoma cells with a focus on CD20. Engagement of Gb(3)/CD77 with SLT-B reduced the amount of CD20 and CXCR4 available, but levels of BCR, MHC Class II, CD21, CD27 and CD54 remained unchanged. Cholesterol depletion promoted a decrease in the number of sites accessed by CD20, CXCR4 and Gb(3)/CD77 antibodies. Constitutive localisation of Gb(3)/CD77 to lipid rafts was unperturbed by either SLT-B binding or cholesterol depletion, whereas the opposite was true for CD20. The effects were specific to SLT-B, highlighted by the inability of cholera toxin B-subunit to alter CD20 availability. Thus, the binding of Gb(3)/CD77 by its cognate ligand transmits information within the lipid bilayer of model lymphoma cells to impact the behaviour of selective proteins, most notably CD20, via a mechanism influenced by the level of cholesterol within the membrane. 相似文献
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Soy protein has been extracted and differently treated to yield products of diverse desirable characteristics. Generally, synthetic chemicals (NaOH and HCl) are used to extract the protein from n-hexane-defatted soy flour (DF). Some researchers have tried to extract it from full-fat flour (FF) using natural chemicals (NC) in response to the ever-increasing consumer preference for naturally processed foods. The effects of these chemicals on the structure of the resultant protein product are not known. This study examined oxidative and structural modification effects of NC and SC as they interact with proteins in the DF and FF systems. Significant differences (p?<?0.01) were observed in all samples in lipoxygenase activity, degree of oxidation, free and total sufhydryl content and intrinsic fluorescence, which indicated increased structural changes in the FF-based samples as compared to those prepared from DF. Circular dichroism spectroscopy showed existence of α-helices and β-sheets protein secondary structures. However, DF samples showed increase in unordered structural conformation changes than the FF sample. Surface hydrophobicity and size exclusion chromatography results were more related to the extraction chemicals than the type of flour used, with samples prepared with SC showing an increase. That’s, the use of natural and synthetic protein extraction chemicals from FF and DF have different effects on the structure and degree of oxidation of the resultant proteins. 相似文献
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Kun Li Yanfang Lan Houqiang Luo Hui Zhang Dongyu Liu Lihong Zhang Rui Gui Lei Wang Muhammad Shahzad Suolang Sizhu Jiakui Li Yangzom Chamba 《The Korean journal of parasitology》2016,54(5):645-652
Toxocara vitulorum has been rarely reported in yaks at high altitudes and remote areas of Sichuan Province of Tibetan Plateau of China. The current study was designed to investigate the prevalence, associated risk factors, and phylogenetic characteristics of T. vitulorum in yak calves on the Qinghai Tibetan plateau. Fecal samples were collected from 891 yak calves and were examined for the presence of T. vitulorum eggs by the McMaster technique. A multivariable logistic regression model was employed to explore variables potentially associated with exposure to T. vitulorum infection. T. vitulorum specimens were collected from the feces of yaks in Hongyuan of Sichuan Province, China. DNA was extracted from ascaris. After PCR amplification, the sequencing of ND1 gene was carried out and phylogenetic analyses was performed by MEGA 6.0 software. The results showed that 64 (20.1%; 95% CI 15.8–24.9%), 75 (17.2; 13.8–21.1), 29 (40.9; 29.3–53.2), and 5 (7.6; 2.5–16.8) yak calves were detected out to excrete T. vitulorum eggs in yak calve feces in Qinghai, Tibet, Sichuan, and Gansu, respectively. The present study revealed that high infection and mortality by T. vitulorum is wildly spread on the Qinghai Tibetan plateau, China by fecal examination. Geographical origin, ages, and fecal consistencies are the risk factors associated with T. vitulorum prevalence by logistic regression analysis. Molecular detection and phylogenetic analysis of ND1 gene of T. vitulorum indicated that T. vitulorum in the yak calves on the Qinghai Tibetan plateau are homologous to preveiously studies reported. 相似文献
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Development and Validation of PCR Primers To Assess the Diversity of Clostridium spp. in Cheese by Temporal Temperature Gradient Gel Electrophoresis 下载免费PDF全文
Anne-Gaëlle Le Bourhis Katiana Saunier Joël Dor Jean-Philippe Carlier Jean-Franois Chamba Michel-Robert Popoff Jean-Luc Tholozan 《Applied microbiology》2005,71(1):29-38
A nested-PCR temporal temperature gradient gel electrophoresis (TTGE) approach was developed for the detection of bacteria belonging to phylogenetic cluster I of the genus Clostridium (the largest clostridial group, which represents 25% of the currently cultured clostridial species) in cheese suspected of late blowing. Primers were designed based on the 16S rRNA gene sequence, and the specificity was confirmed in PCRs performed with DNAs from cluster I and non-cluster I species as the templates. TTGE profiles of the PCR products, comprising the V5-V6 region of the 16S rRNA gene, allowed us to distinguish the majority of cluster I species. PCR-TTGE was applied to analyze commercial cheeses with defects. All cheeses gave a signal after nested PCR, and on the basis of band comigration with TTGE profiles of reference strains, all the bands could be assigned to a clostridial species. The direct identification of Clostridium spp. was confirmed by sequencing of excised bands. C. tyrobutyricum and C. beijerinckii contaminated 15 and 14 of the 20 cheese samples tested, respectively, and C. butyricum and C. sporogenes were detected in one cheese sample. Most-probable-number counts and volatile fatty acid were determined for comparison purposes. Results obtained were in agreement, but only two species, C. tyrobutyricum and C. sporogenes, could be isolated by the plating method. In all cheeses with a high amount of butyric acid (>100 mg/100 g), the presence of C. tyrobutyricum DNA was confirmed by PCR-TTGE, suggesting the involvement of this species in butyric acid fermentation. These results demonstrated the efficacy of the PCR-TTGE method to identify Clostridium in cheeses. The sensitivity of the method was estimated to be 100 CFU/g. 相似文献
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藏猪繁殖性状多基因效应分析 总被引:4,自引:0,他引:4
藏猪是我国特有的高原型地方猪种, 具有适应高海拔恶劣气候环境、抗病、耐粗、肉质鲜美等特点, 但繁殖力低。文章以促卵泡素b亚基(FSHb)、雌激素受体(ESR)、促乳素受体(PRLR)和视黄醛结合蛋白4(RBP4)等基因作为繁殖性状主要候选基因, 测定76头藏猪的基因型, 分析单基因和多基因合并对繁殖性状的影响效应。结果说明, 在藏猪群体中, FSHb、ESR和PRLR基因不同基因型繁殖性状差异显著, 优良基因型分别为BB、BB和AA。藏猪RBP4基因只有2种基因型, 对繁殖性状影响不显著。FSHb-ESR-PRLR基因的合并优良基因型为BB-BB-AA, 多基因聚合效应高于单基因效应。 相似文献