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101.
Qu Yaqian Chen Siyu Zhou Lei Chen Min Li Lin Ni Yihan Sun Jingquan 《Molecular biology reports》2022,49(9):8507-8516
Molecular Biology Reports - Lactate is an important product of glycolysis metabolism during exercise and has long been recognized as an important metabolic signaling molecule involved in inhibiting... 相似文献
102.
Tian Fang Qin Wen Zhang Ran Herzschuh Ulrike Ni Jian Zhang Chengjun Mischke Steffen Cao Xianyong 《Vegetation History and Archaeobotany》2022,31(6):549-558
Vegetation History and Archaeobotany - The terrestrial ecosystem in the Yellow River Source Area (YRSA) is sensitive to climate change and human impacts, although past vegetation change and the... 相似文献
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黑老虎的根是常用中药,黄酮类化合物是药用植物的主要活性成分之一。为探究黑老虎植株叶和茎中可能含有与根类似或具有高度富集的类黄酮化合物,挖掘其利用价值。该文利用广泛靶向代谢组学技术,鉴定了黑老虎的叶、茎和根的代谢物,并根据结构配置分类,解析其中类黄酮的多样性和丰度。结果表明:(1)黑老虎叶中类黄酮数量(80个)>茎(73个)>根(67个),3个部位均有61个相同的黄酮类化合物,叶和茎中含有更多的黄酮醇类化合物,从而使类黄酮多样性高于根。(2)在3个部位积累量比较高的是黄酮醇类、黄酮类、黄烷醇类和查尔酮类,其中黄酮醇和黄酮在茎和根积累量下降,导致类黄酮丰度从叶(24.00 × 107)-茎(13.45 × 107)-根(9.05 × 107)连续大幅度下调。(3)叶和茎中含有大量与根相同和多种根中没有的类黄酮,可以考虑替代或互补利用,3个部位儿茶素类化合物表达量都较高,叶中还富含槲皮素及其衍生物,具有较高的利用价值。 相似文献
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Alexandra M. Lopes Kenneth I. Aston Emma Thompson Filipa Carvalho Jo?o Gon?alves Ni Huang Rune Matthiesen Michiel J. Noordam Inés Quintela Avinash Ramu Catarina Seabra Amy B. Wilfert Juncheng Dai Jonathan M. Downie Susana Fernandes Xuejiang Guo Jiahao Sha António Amorim Alberto Barros Angel Carracedo Zhibin Hu Matthew E. Hurles Sergey Moskovtsev Carole Ober Darius A. Paduch Joshua D. Schiffman Peter N. Schlegel Mário Sousa Douglas T. Carrell Donald F. Conrad 《PLoS genetics》2013,9(3)
Gonadal failure, along with early pregnancy loss and perinatal death, may be an important filter that limits the propagation of harmful mutations in the human population. We hypothesized that men with spermatogenic impairment, a disease with unknown genetic architecture and a common cause of male infertility, are enriched for rare deleterious mutations compared to men with normal spermatogenesis. After assaying genomewide SNPs and CNVs in 323 Caucasian men with idiopathic spermatogenic impairment and more than 1,100 controls, we estimate that each rare autosomal deletion detected in our study multiplicatively changes a man''s risk of disease by 10% (OR 1.10 [1.04–1.16], p<2×10−3), rare X-linked CNVs by 29%, (OR 1.29 [1.11–1.50], p<1×10−3), and rare Y-linked duplications by 88% (OR 1.88 [1.13–3.13], p<0.03). By contrasting the properties of our case-specific CNVs with those of CNV callsets from cases of autism, schizophrenia, bipolar disorder, and intellectual disability, we propose that the CNV burden in spermatogenic impairment is distinct from the burden of large, dominant mutations described for neurodevelopmental disorders. We identified two patients with deletions of DMRT1, a gene on chromosome 9p24.3 orthologous to the putative sex determination locus of the avian ZW chromosome system. In an independent sample of Han Chinese men, we identified 3 more DMRT1 deletions in 979 cases of idiopathic azoospermia and none in 1,734 controls, and found none in an additional 4,519 controls from public databases. The combined results indicate that DMRT1 loss-of-function mutations are a risk factor and potential genetic cause of human spermatogenic failure (frequency of 0.38% in 1306 cases and 0% in 7,754 controls, p = 6.2×10−5). Our study identifies other recurrent CNVs as potential causes of idiopathic azoospermia and generates hypotheses for directing future studies on the genetic basis of male infertility and IVF outcomes. 相似文献
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Qinghong Wang Jijun Zhou Bei Zhang Zhiqiang Tian Jun Tang Yanhua Zheng Zemin Huang Yi Tian Zhengcai Jia Yan Tang Jennifer C. van Velkinburgh Qing Mao Xiuwu Bian Yifang Ping Bing Ni Yuzhang Wu 《PLoS pathogens》2013,9(6)
IL-23 regulates myriad processes in the innate and adaptive immune systems, and is a critical mediator of the proinflammatory effects exerted by Th17 cells in many diseases. In this study, we investigated whether and how hepatitis B virus (HBV) causes liver damage directly through the IL-23 signaling pathway. In biopsied liver tissues from HBV-infected patients, expression of both IL-23 and IL-23R was remarkably elevated. In vivo observations also indicated that the main sources of IL-23 were myeloid dendritic cells (mDCs) and macrophages. Analysis of in vitro differentiated immature DCs and macrophages isolated from healthy donors revealed that the HBV surface antigen (HBsAg) efficiently induces IL-23 secretion in a mannose receptor (MR)-dependent manner. Culture with an endosomal acidification inhibitor and the dynamin inhibitor showed that, upon binding to the MR, the HBsAg is taken up by mDCs and macrophages through an endocytosis mechanism. In contrast, although the HBV core antigen (HBcAg) can also stimulate IL-23 secretion from mDCs, the process was MR- and endocytosis-independent. In addition, IL-23 was shown to be indispensible for HBsAg-stimulated differentiation of naïve CD4+ T cells into Th17 cells, which were determined to be the primary source of IL-17 in HBV-infected livers. The cognate receptor, IL-17R, was found to exist on the hepatic stellate cells and mDCs, both of which might represent the potential target cells of IL-17 in hepatitis B disease. These data provide novel insights into a yet unrecognized mechanism of HBV-induced hepatitis, by which increases in IL-23 expression, through an MR/endocytosis-dependent or -independent manner, produce liver damage through the IL-23/IL-17 axis. 相似文献
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The objective of this study was to develop a water-in-oil (w/o) microemulsion which can be utilized as a transdermal delivery for iodide ions. Several w/o microemulsion formulations were prepared utilizing Span 20, ethanol, Capryol 90®, and water. The selected formulations had 5%, 10%, 15%, 20%, and a maximum of 23% w/w water content. Potassium iodide (KI) was incorporated in all formulations at 5% w/v. Physicochemical characterizations were conducted to evaluate the structure and stability. These studies included: mean droplet size, pH, viscosity, conductivity, and chemical stability tests. In vitro human skin permeation studies were conducted to evaluate the diffusion of the iodide ion through human skin. The w/o microemulsion formulations were stable and compatible with iodide ions with water content ranging from 5% to 23% w/w. The addition of KI influenced the physicochemical properties of microemulsion as compared to blank microemulsion formulations. In vitro human skin permeation studies indicated that selected formulations improved iodide ion diffusion significantly as compared to control (KI solution; P value < 0.05). Iodide ions were entrapped within the aqueous core of w/o microemulsion. Span 20, ethanol and Capryol 90 protected the iodide ions against oxidation and formed a stable microemulsion. It is worth to note that according to Hofmeister series, iodide ions tend to lower the interfacial tension between water and oil and consequently enhance overall stability. This work illustrates that microemulsion system can be utilized as a vehicle for the transdermal administration of iodide.KEY WORDS: iodide, microemulsion, skin permeation, transdermal 相似文献