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31.
《Biomarkers》2013,18(6-7):355-364
Abstract

Objective: To study the impact of genetic and lifestyle factors on protein biomarkers and develop personally normalized plasma protein profiles (PNPPP) controlling for non-disease-related variance.

Materials and methods: Proximity extension assays were used to measure 145 proteins in 632 controls and 344 cases with non-communicable diseases.

Results: Genetic and lifestyle factors explained 20–88% of the variation in healthy controls. Adjusting for these factors reduced the number of candidate biomarkers by 63%.

Conclusion: PNPPP efficiently controls for non-disease-related variance, allowing both for efficient discovery of novel biomarkers and for covariate-independent linear cut-offs suitable for clinical use.  相似文献   
32.
BackgroundTrace elements are important factors in human reproductive health. Among them, special attention is paid to zinc, which is an essential trace element and is necessary for the normal functioning of the male reproductive system and the process of spermatogenesis. The aim of the study was to investigate the association between seminal and serum zinc concentrations and semen quality and reproductive hormone levels in population of Russian young men.MethodsThe study population consisted of 626 young Russian men (median age 22.5 years), recruited from the general population, regardless of their fertility status. Each participant provided semen and blood sample, information about his lifestyle and ethnicity. Semen quality (sperm concentration, motility and morphology), reproductive hormone levels (testosterone, estradiol, LH, FSH and inhibin B), and serum and seminal zinc concentrations were evaluated. The semen samples were analyzed according to the WHO laboratory manual (WHO, 2010). Serum hormones were measured by enzyme immunoassay, zinc concentrations were determined using spectrophotometry and direct colorimetry without deproteinization.ResultsZinc was present in the seminal plasma in a significantly higher concentration than in the blood serum (median serum Zn concentration was 23.6 μmol/L vs seminal Zn concentration 1571.8 μmol/L). The seminal zinc concentration was positively related to the total sperm count, sperm concentration, progressive motility and normal morphology (Spearman’s test: 0.221; 0.286; 0.269; 0.183, respectively, p < 0.001), while the serum Zn concentration was negatively related to serum testosterone and estradiol levels (r = −0.249 and r = −0.096, respectively, p < 0.001−0.05). It was found that the seminal Zn content in men with normal semen quality was higher compared to men with lowered semen quality (means: 6.37 and 5.03 μmol/ejaculate, respectively, p < 0.001). Similarly, the semen volume, total sperm count, sperm concentration, progressive motility, normal morphology and the serum testosterone level in men with the seminal Zn deficiency were lower than in men with the normal seminal Zn content.ConclusionBased on the results of our population-based study, seminal Zn levels were closely associated with semen parameters in young men, so Zn deficiency may be an important risk factor for lowered semen quality. Seminal Zn determinations should be considered as a useful tool in addition to other parameters in assessing male fertility.  相似文献   
33.
The most fundamental property of biomarkers is change. But changes are hard to maintain in plasma since it is strictly controlled by homeostatic mechanisms of the body. There is no homeostatic mechanism for urine. Besides, urine is partly a filtration of blood, and systematic information can be reflected in urine. We hypothesize that change of blood can be reflected in urine more sensitively. Here we introduce the interference into the blood by two anticoagulants heparin or argatroban. Plasma and urine proteins were profiled by LC-MS/MS and then validated by Western blot in totally six SD female rats before and after the drug treatments. In argatroban treated group, with exactly the same experimental procedure and the same cutoff value for both plasma and urine proteins, 62 proteins changed in urine, only one of which changed in plasma. In heparin treated group, 27 proteins changed in urine but only three other proteins changed in plasma. Both LC-MS/MS and Western blot analyses demonstrated drug-induced increases in transferrin and hemopexin levels in urine but not in plasma. Our data indicates that urine may serve as a source for more sensitive detection of protein biomarkers than plasma.  相似文献   
34.
Hepatocytes were isolated from thioacetamide (TAA)-induced macronodular cirrhotic rat livers by a collagenase perfusion method. In the content of cellular metabolites, fatty acid uptake and lipid secretion there were no substantial differences compared with cells isolated from micronodular cirrhosis described previously. In contrast to isolated hepatocytes from normal livers those from macronodular cirrhosis had a lowered cellular content of triglycerides, phospholipids and cholesterol but not of cholesterol esters and free fatty acids. In macronodular cirrhosis hepatocytes of hypertrophic type, rich in cell organelles, can be distinguished ultrastructurally from those with signs of atrophy and degeneration. Immediately after isolation many hepatocytes isolated from macronodular cirrhosis showed plasma membrane blebbing. Whereas the blebbing was without recognizable effects on the fine structure of the isolated hepatocytes of the hypertrophic type, in the more atrophic ones some mitochondria were swollen. In addition, morphological analysis of the crude and purified suspensions revealed a partial selection of the hypertrophic cells during the isolation procedure, presumably due to a more labile state of those cells which showed signs of atrophy and degeneration. When stabilized in the suspension medium, however, the hepatocytes maintained complex metabolic functions for at least 2 h. Thus, the method described allows the isolation of parenchymal cells from TAA-induced macronodular cirrhotic livers for studying ultrastructural and biochemical alterations in hyperregenerative experimental liver cirrhosis.  相似文献   
35.
Summary. Immunoblotting with antiserum specific to human Gc protein was used to identify Gc protein as the previously reported polymorphic plasma postalbumin (Po) of llamas and alpacas. This is the first report of Gc polymorphism in camelid species. One Gc variant appeared to be identical in llamas, alpacas, dromedaries and bactrian camels.  相似文献   
36.
Glycosaminoglycans were isolated from plasma membranes of hepatic and renal tubule cells of guinea pig. Plasmalemma of renal tubule cells contained more total glycosaminoglycans, hyaluronic acid, chondroitin-4 sulfates and chondroitin-6 sulfates, and less dermatan sulfates and heparin sulfates than liver plasma membranes. These glycocalyx components, owing to their polyanionic properties, may have a role in the transport of water, ions, and macromolecules across the cell membrane.  相似文献   
37.
SYNOPSIS. The structure of Trepomonas agilis communis Klebs is described from light and electron microscope observations on 2 clone isolates of the organism. The surface membrane shows marked differentiation into an extremely thick (16 nm) symmetric membrane which covers the greater part of the body, and a thinner (∼ 10–12 nm) asymmetric membrane which lines the 2 lateral oral grooves and the posterior channel connecting them; a similar asymmetric membrane covers the flagella. Thorium dioxide staining suggests a denser distribution of acidic carbohydrate groups on the asymmetric membrane. The pathways of cytoplasmic streaming observed in the living flagellate coincide with those of microtubule bands arising close to the flagellar basal bodies and it is suggested that the bands play an orienting role in the streaming of food vacuoles. The contractile vacuole undergoes diastole in the anterior (postnuclear) cytoplasm, and is formed by coalescence of smaller vesicles. At systole the entire vacuole migrates to the posterior extremity to discharge into the posterior channel; the route of exit lacks guiding structural elements. Features of the flagellate's physiology and organization are discussed in relation to the observed lack of mitochondria, microbodies and Golgi apparatus in diplomonads.  相似文献   
38.
采用自动在线纳流多维液相色谱 串联质谱联用的方法分离和鉴定蔗糖密度梯度离心法分离和富集的小鼠肝脏质膜蛋白质 .以强阳离子交换柱为第一相 ,反相柱为第二相 ,在两相之间连接一预柱脱盐和浓缩肽段 .用含去污剂的溶剂提取细胞质膜中的蛋白质 ,获得的质膜蛋白质经酶解和适当的酸化后通过离子交换柱吸附 ,分别用 10个不同浓度的乙酸铵盐溶液进行分段洗脱 .洗脱物经预柱脱盐和浓缩后进入毛细管反相柱进行反相分离 ,分离后的肽段直接进入质谱仪离子源进行一级和二级质谱分析 .质谱仪采得的数据经计算机处理后用Mascot软件进行蛋白质数据库搜寻 ,共鉴定出 12 6种蛋白质 ,其中 4 1种为膜蛋白 ,包括与膜相关的蛋白质和具有多个跨膜区的整合膜蛋白 ,为建立质膜蛋白质组学研究的适宜方法和质膜蛋白质数据库提供了有价值的基础性研究资料 .  相似文献   
39.
对基因工程构建的含人胰高血糖素样肽1(hGLP1)突变体的工程菌株进行诱导表达,分离纯化N末端第二位突变的2GlyhGLP1突变体.IPTG诱导4h,收获的菌体经超声破碎后,裂解液用GlutathioneSepharose4B亲和层析纯化GST2GlyhGLP1融合蛋白,经CNBr裂解、SephadexG25柱脱盐、QAESepharoseFF阴离子交换柱层析和RPC18柱脱盐,得到纯度大于98%的重组2GlyhGLP1.Western印迹分析证实,该突变体可被特异性hGLP1抗体所识别.生物学活性分析表明,2GlyhGLP1具有明显的降血糖活性和促胰岛素分泌活性(P<0.001).  相似文献   
40.
Hydrolytic activities of the H+-ATPase were compared for plasma membrane fractions isolated from coleoptile cells of 3-, 4-, and 5-day-old etiolated maize seedlings. The membrane preparations obtained by differential centrifugation were additionally purified in the gradient of sucrose density and in the polyethylene glycol-dextran system. The highest level of ATP-hydrolyzing activity was observed in the plasmalemma fraction obtained from 4-day-old seedlings. The pattern of age-dependent changes in H+-ATPase activity of the plasma membranes was clearly different from the monotonic deceleration of coleoptile cell elongation in the period examined. It is supposed that changes in ATPase activity reflect different regulatory roles of this principal ion-transporting enzyme of the plasma membrane at the stage of cell elongation and at a later developmental stage when the coleoptile has completed its physiological function.__________Translated from Fiziologiya Rastenii, Vol. 52, No. 4, 2005, pp. 566–572.Original Russian Text Copyright © 2005 by Rudashevskaya, Kirpichnikova, Shishova.  相似文献   
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