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131.
Mei Zeng Baofeng Chen Yufeng Qing Wenguang Xie Wantai Dang Mingcai Zhao 《Nucleosides, nucleotides & nucleic acids》2013,32(7):455-465
Glut9 is highly expressed in the human kidney proximal convoluted tubular and plays a crucial role in the regulation of plasma urate levels. The gene effects were stronger among women. Our results show that 17-β-estradiol (E2) through ER (estrogen receptor) β downregulates Glut9 protein expression on human renal tubular epithelial cell line (HK2). Intriguingly, E2 does not affect the expression of Glut9 mRNA. ERβ is linked to PTEN, the PTEN gene negatively regulates the PI3K/AKT pathway, and the PI3K/AKT pathway inhibition may lead to autophagy. Further study indicates that ERβ may affect the expression of Glut9 though autophagy. 相似文献
132.
William B. Parker Sue C. Shaddix Lucy M. Rose Phuong T. Pham Mei Hua Robert Vince 《Nucleosides, nucleotides & nucleic acids》2013,32(4):795-804
Abstract The metabolism of O6-propyl-carbovir and N6-propyl-carbovir, two selective inhibitors of HIV replication, has been evaluated in CEM cells. Both compounds were phosphorylated in intact cells to carbovir-5′-triphosphate. The metabolism of these two agents was inhibited by deoxycoformycin and mycophenolic acid, but not erythro-9-(2-hydroxy-3-nonyl)adenine. No evidence of the 5′-triphosphate of either compound was detected in CEM cells. 相似文献
133.
Jiannan Yang Zhaoying Liu Mei Li Xinghui Qiu 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2013,158(2):84-90
Quinoxaline derivatives (quinoxalines) comprise a class of drugs that have been widely used as animal antimicrobial agents and feed additives. Although the metabolism of quinoxaline drugs has been mostly studied using chicken liver microsomes, the biochemical mechanism of biotransformation of these chemicals in the chicken has yet to be characterized. In this study, using bacteria produced enzymes, we demonstrated that both CYP1A4 and CYP1A5 participate in the oxidative metabolism of quinoxalines. For CYP1A5, three hydroxylated metabolites of quinocetone were generated. In addition, CYP1A5 is able to hydroxylate carbadox. For CYP1A4, only one hydroxylated product of quinocetone on the phenyl ring was identified. Neither CYP1A5 nor CYP1A4 showed hydroxylation activity towards mequindox and cyadox. Our results suggest that CYP1A4 and CYP1A5 have different and somewhat overlapping substrate specificity in quinoxaline metabolism, and CYP1A5 represents a crucial enzyme in hydroxylation of both quinocetone and carbadox. 相似文献
134.
Fagen Li Fan Yang Qijie Weng Guangtian Yin Mei Li Siming Gan 《Molecular breeding : new strategies in plant improvement》2013,31(4):867-877
Rattans serve as an important source of raw non-wood materials for furniture and handicraft industries worldwide. However, their genomic sequence information in public databases is very limited. In this study, a set of 2,528 good-quality expressed sequence tags (ESTs) were generated from a full-length cDNA library constructed previously with root, stem and male inflorescence tissues of Calamus simplicifolius C. F. Wei, a rattan species native to Hainan Island, China. The ESTs were assembled into 1,588 unigenes, including 1,221 singletons and 367 contigs. BlastX searches against the GenBank non-redundant protein database revealed that 1,248 (78.6 %) unigenes had at least one significant match (E ≤ 10?5). The gene ontology functional classification assigned 991, 669 and 977 of the unigenes to the cellular component, molecular function and biological process categories, respectively. A total of 71 simple sequence repeat (SSR) loci were developed among these ESTs, including 65 polymorphic across 19 rattan species representing three genera. High levels of cross-species/genus transferability were observed for the EST-SSRs. For the polymorphic EST-SSR markers, the number of alleles per locus and polymorphic information content ranged from 2 to 25 (mean 11.1) and from 0.135 to 0.949 (mean 0.695), respectively. The EST sequences and the EST-SSR primers have been deposited in GenBank databases of EST (IDs JK838364–40891) and Probe (IDs Pr16718978–9048, to be assigned). 相似文献
135.
Xiao-Long Lu Wen-Xiao Xu Zhen-Yu Yan Zhao Qian Bing Xu Yang Liu Li-Min Han Rui-Chen Gao Jun-Nan Li Mei Yuan Chong-Bao Zhao Guo-fen Qiao Bai-Yan Li 《International journal of biological sciences》2013,9(7):716-727
Nodose ganglia are composed of A-, Ah- and C-type neurons. Despite their important roles in regulating visceral afferent function, including cardiovascular, pulmonary, and gastrointestinal homeostasis, information about subtype-specific expression, molecular identity, and function of individual ion transporting proteins is scarce. Although experiments utilizing the sliced ganglion preparation have provided valuable insights into the electrophysiological properties of nodose ganglion neuron subtypes, detailed characterization of their electrical phenotypes will require measurements in isolated cells. One major unresolved problem, however, is the difficulty to unambiguously identify the subtype of isolated nodose ganglion neurons without current-clamp recording, because the magnitude of conduction velocity in the corresponding afferent fiber, a reliable marker to discriminate subtypes in situ, can no longer be determined. Here, we present data supporting the notion that application of an algorithm regarding to microscopic structural characteristics, such as neuron shape evaluated by the ratio between shortest and longest axis, neuron surface characteristics, like membrane roughness, and axon attachment, enables specific and sensitive subtype identification of acutely dissociated rat nodose ganglion neurons, by which the accuracy of identification is further validated by electrophysiological markers and overall positive predictive rates is 89.26% (90.04%, 76.47%, and 98.21% for A-, Ah, and C-type, respectively). This approach should aid in gaining insight into the molecular correlates underlying phenotypic heterogeneity of nodose ganglia. Additionally, several critical points that help for neuron identification and afferent conduction calibration are also discussed. 相似文献
136.
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138.
Ru Wang Markku Alen Zhusheng Yu Petri Wiklund Shu Mei Cheng Timo T?rm?kangas Peijie Chen Sulin Cheng 《PloS one》2013,8(12)
Vitamin D is well known for its regulatory role in calcium and phosphate homeostasis, but its role in muscle mass and strength during growth remains inconclusive. We explored the association of serum 25-hydroxyvitamin D (25(OH)D) with muscle development in girls from 11 to 18-years old. Whole body lean tissue mass (LMWB), appendicular lean mass (aLM), muscle cross-sectional area at the lower leg (mCSA), maximal voluntary contraction of elbow flexors (MVCelbow) and knee extensors (MVCknee) were assessed in 217 girls aged 10–13 years (at baseline), 215 in 2-year and 226 in 7.5-year follow-up. Serum concentration of 25(OH)D and intact parathyroid hormone (PTH) were analyzed retrospectively and girls were categorized according to their 25(OH)D levels (consistently insufficient 25(OH)D GLL <50 nmol/l and consistently sufficient GHH >50 nmol/l from baseline to 7-year follow-up). We found that 25(OH)D level declined until menarche (p<0.05) while LMWB, aLM, mCSA, MVCelbow and MVCknee continued to increase (p<0.001 for all) post menarche. At pre-menarche, the GLL (n = 34) had higher LMWB and aLM than the GHH (n = 21, p<0.05), while post-menarche the GHH (n = 15) had a greater catch-up gain in LMWB (p = 0.004), aLM (p = 0.001) and mCSA (p = 0.027) compared to the GLL (n = 65) over the first 2-year period. At the age of 18, no differences in muscle mass/strength between the low (n = 151) and high (n = 77) levels of 25(OH)D groups were found. This finding was independent of vitamin D receptor genotype and other confounders. In conclusion, our results showed that levels of 25(OH)D have no significant negative influence on the development of muscle mass and strength during pubertal growth both with longitudinal and cross-sectional comparison. On the contrary, our results suggest that the temporary negative association between 25(OH)D and muscle mass arises as a consequence of fast growth prior to menarche, and this negative association is diminished through catch-up growth after menarche. 相似文献
139.
Guangbin Liu Ruize Liu Qinqun Li Xiaohui Tang Mei Yu Xinyun Li Jianhua Cao Shuhong Zhao 《PloS one》2013,8(10)
Background
Wool quality is one of the most important economic traits in sheep. The wool fiber is derived from specialized skin cells that are referred to as wool follicles. To understand the roles of microRNAs (miRNAs) in wool fiber growth, we detected the expression patterns of miRNAs in wool follicles at the anagen, catagen, and telogen stages from Tibetan sheep through Solexa sequencing.Results
A total of 244 mature miRNAs were identified. Of these, only five miRNAs are listed in the database of sheep miRNAs (miRBase Database V19), and the other 239 miRNAs have not been previously described in this species. Further analyses indicated that 204 miRNAs are evolutionarily conserved among mammal species, whereas 35 of the identified miRNAs were first found specifically in sheep. The expression pattern analyses showed that the expression levels of 39, 34, and 20 of the miRNAs significantly change between anagen and catagen, between anagen and telogen, and between catagen and telogen, respectively. The results of the bioinformatics analysis show that these differentially expressed miRNAs might regulate wool follicle development by targeting genes in many different pathways, such as the MAPK and Wnt pathways, as well as the pathways that regulate the actin cytoskeleton, focal adhesion, and tight junctions. Furthermore, we identified six differentially expressed miRNAs (oar-miR-103-3P, oar-miR-148b-3P, oar-miR-320-3P, oar-miR-31-5P, oar-novel-1-5P, and oar-novel-2-3P) that might target the key genes of the Wnt pathway. It has been reported that the Wnt pathway is critical for wool follicle development. Therefore, these miRNAs may regulate wool development through the Wnt pathway.Conclusions
Our results provide new information on the identification and expression pattern of miRNAs in wool follicles. Our data might therefore aid in the understanding of the mechanisms of wool follicle development in sheep. 相似文献140.
Xin-Xia Feng Mei Liu Wei Yan Zhen-Zhen Zhou Yu-Jia Xia Wei Tu Pei-Yuan Li De-An Tian 《PloS one》2013,8(11)
In addition to being an important mediator of migration and invasion of tumor cells, β3 integrin can also enhance TGF-β1 signaling. However, it is not known whether β3 might influence the induction of metastatic phenotype of tumor cells, especially non-metastatic tumor cells which express low level of β3. Here we report that H2O2 and HOCl, the reactive oxygen species produced by neutrophils, could cooperate with TGF-β1 to induce metastatic phenotype of non-metastatic hepatocellular carcinoma (HCC) cells. TGF-β1/H2O2/HOCl, but not TGF-β1 or H2O2/HOCl, induced β3 expression by triggering the enhanced activation of p38 MAPK. Intriguingly, β3 in turn promoted TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of HCC cells by enhancing TGF-β1 signaling. β3 promoted TGF-β1/H2O2/HOCl-induced expression of itself via positive feed-back effect on p38 MAPK activation, and also promoted TGF-β1/H2O2/HOCl-induced expression of α3 and SNAI2 by enhancing the activation of ERK pathway, thus resulting in higher invasive capacity of HCC cells. By enhancing MAPK activation, β3 enabled TGF-β1 to augment the promoting effect of H2O2/HOCl on anoikis-resistance of HCC cells. TGF-β1/H2O2/HOCl-induced metastatic phenotype was sufficient for HCC cells to extravasate from circulation and form metastatic foci in an experimental metastasis model in nude mice. Inhibiting the function of β3 could suppress or abrogate the promoting effects of TGF-β1/H2O2/HOCl on invasive capacity, anoikis-resistance, and extravasation of HCC cells. These results suggest that β3 could function as a modulator to promote TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of non-metastatic tumor cells, and that targeting β3 might be a potential approach in preventing the induction of metastatic phenotype of non-metastatic tumor cells. 相似文献