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121.
Cavarra MS del Mónaco SM Assef YA Ibarra C Kotsias BA 《The Journal of membrane biology》2007,219(1-3):49-61
The human ether-a-go-go related gene (HERG1) K+ channel is expressed in neoplastic cells, in which it was proposed to play a role in proliferation, differentiation and/or
apoptosis. K562 cells (a chronic myeloid leukemic human cell line) express both the full-length (herg1a) and the N-terminally
truncated (herg1b) isoforms of the gene, and this was confirmed with Western blots and coimmunoprecipitation experiments.
Whole-cell currents were studied with a tail protocol. Seventy-eight percent of cells showed a HERG1-like current: repolarization
to voltages negative to −40 mV produced a transient peak inward tail current, characteristic of HERG1 channels. Cells were exposed to a HERG-specific channel
blocker, E4031. Half-maximal inhibitory concentration (IC50) of the blocker was 4.69 nm. The kinetics of the HERG1 current in K562 cells resembled the rapid component of the native cardiac delayed rectifier current,
known to be conducted by heterotetrameric HERG1 channels. Fast and slow deactivation time constants at −120 mV were 27.5 and 239.5 ms, respectively. Our results in K562 cells suggest the assembling of heterotetrameric channels, with
some parameters being dominated by one of the isoforms and other parameters being intermediate. Hydrogen peroxide was shown
to increase HERG1a K+ current in heterologous expression systems, which constitutes an apoptotic signal. However, we found that K562 HERG1 whole-cell
currents were not activated by H2O2. 相似文献
122.
123.
Qichen Yang MSc Vishal Jhanji MD Sze Qin Tan BSc Kwok Ping Chan BSc Di Cao PhD Wai Kit Chu DPhil Mingzhi Zhang MD Chi Pui Pang DPhil Tsz Kin Ng PhD 《Journal of cellular biochemistry》2019,120(3):4203-4213
Pterygium is a triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. Our previous meta-analysis found that cigarette smoking is associated with a reduced risk of pterygium. Yet, the biological effect of cigarette smoke components on pterygium has not been studied. Here we reported the proliferation and migration properties of human primary pterygium cells with continuous exposure to nicotine and cotinine. Human primary pterygium cells predominantly expressed the α5, β1, and γ subunits of the nicotinic acetylcholine receptor. Continuous exposure to the mixture of 0.15 μM nicotine and 2 μM cotinine retarded pterygium cell proliferation by 16.04% (P = 0.009) and hindered their migration by 11.93% ( P = 0.039), without affecting cell apoptosis. SNAIL and α-smooth muscle actin protein expression was significantly downregulated in pterygium cells treated with 0.15 μM nicotine-2 μM cotinine mixture by 1.33- ( P = 0.036) and 1.31-fold ( P = 0.001), respectively. Besides, the 0.15 μM nicotine-2 μM cotinine mixture also reduced matrix metalloproteinase (MMP)-1 and MMP-9 expressions in pterygium cells by 1.56- ( P = 0.043) and 1.27-fold ( P = 0.012), respectively. In summary, this study revealed that continuous exposure of nicotine and cotinine inhibited human primary pterygium cell proliferation and migration in vitro by reducing epithelial-to-mesenchymal transition and MMP protein expression, partially explaining the lower incidence of pterygium in cigarette smokers. 相似文献
124.
Tienan Wang MD Baolin Wu MD Xiuzhi Zhang MD Meng Zhang MD Shuo Zhang MD Wei Huang MD Tao Liu MD Weiting Yu MD Junlei Li MD Xiaobing Yu MD 《Journal of cellular biochemistry》2019,120(5):6988-6997
Spinal cord injury (SCI) is characterized by dramatic neurons loss and axonal regeneration suppression. The underlying mechanism associated with SCI-induced immune suppression is still unclear. Weighted gene coexpression network analysis (WGCNA) is now widely applied for the identification of the coexpressed modules, hub genes, and pathways associated with clinic traits of diseases. We performed this study to identify hub genes associated with SCI development. Gene Expression Omnibus (GEO) data sets GSE45006 and GSE20907 were downloaded and the significant correlativity and connectivity between them were detected using WGCNA. Three significant consensus modules, including 567 eigengenes, were identified from the master GSE45006 data following the preconditions of approximate scale-free topology for WGCNA. Further bioinformatics analysis showed these eigengenes were involved in inflammatory and immune responses in SCI. Three hub genes Rac2, Itgb2, and Tyrobp and one pathway “natural killer cell-mediated cytotoxicity” were identified following short time-series expression miner, protein-protein interaction network, and functional enrichment analysis. Gradually upregulated expression patterns of Rac2, Itgb2, and Tyrobp genes at 0, 3, 7, and 14 days after SCI were confirmed based on GSE45006 and GSE20907 data set. Finally, we found that Rac2, Itgb2, and Tyrobp genes might take crucial roles in SCI development through the “natural killer cell–mediated cytotoxicity” pathway. 相似文献
125.
Özgür Yiğiter MD Ali Cagdas Yorukoglu MD Nilay Şentürk MD Yavuz Dodurga MD Ahmet Fahir Demirkan MD 《Journal of cellular biochemistry》2019,120(7):11525-11530
The aim of this study is to investigate the effects of type I collagen on bone defects and on genes specifically for osteogenesis in a rat model. Two millimeter drill hole bone defect was created in the femur of rats. In the experimental group, type I collagen was applied in bone defects whereas in control group defects were left empty. Inflammation, development of connective tissue, osteogenesis, and foreign body reaction parameters evaluated with histologically and genes evaluated by blood samples. In the experimental group, the histopathologically significant change was found in favor of bone healing only at the first week. A significant increase was found in genetic expressions of BMP-1, 2, 3, 4, 5, 6, 7, TGF-βRII, Smad-1, IL-6, BMPR-IA, BMPR-IB, Eng, BMPR-II, c-fos, Cdkn1a, Chrd, Gdf-5, Id-1, PDGF-β, IGF-1, Serpine-1, and TGF-βRI at the first hour. At the first, third, and sixth week, no significant increase was found in any of the gene expressions. Type I collagen is found to be effective in favor of bone healing through increased inflammatory cytokines and expression of BMP genes in the early stages of fracture healing. 相似文献
126.
Peizhong Zheng MD Ali Babar Seshasai Parthasarathy Ryan Gibson Kelly Parliament Josh Flook Thomas Patterson Peter Friedemann Siva Kumpatla Steve Thompson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(7):1537-1547
Key message
We identified a G-nucleotide insertion in a maize FatB responsible for reducing saturated fatty acids through QTL mapping and map-based cloning and developed an allele-specific DNA marker for molecular breeding.Abstract
Vegetable oils with reduced saturated fatty acids have signficant health benefits. SRS72NE, a Dow AgroSciences proprietory maize inbred line, was found to contain signficantly reduced levels of palmitic acid and total saturated fatty acids in seed oil when compared to other common inbreds. Using F2 and F3 populations derived from a cross between SRS72NE and a normal inbred SLN74, we have demonstrated that the reduced saturated fatty acid phenotype in SRS72NE is controlled by a single QTL on chromosome 9 that explains 79.1 % of palmitic acid and 79.6 % total saturated fatty acid variations. The QTL was mapped to an interval of 105 kb that contains one single gene, a type B fatty acyl-ACP thioesterase (ZmFatB; GRMZM5G829544). ZmFatB alleles from SRS72NE and common inbreds were cloned and sequenced. SRS72NE fatb allele contains a single nucleotide (G) insertion in the 6th exon, which creates a premature stop codon 22 base pairs down stream. As a result, ZmFatB protein from SRS72NE is predicted to contain eight altered and 90 deleted amino acids at its C-terminus. Because the affected region is part of the conserved acyl-ACP thioesterase catalytic domain, the truncated ZmFatB in SRS72NE is likely non-functional. We also show that fatb RNA level in SRS72NE is reduced by 4.4-fold when compared to the normal allele SNL74. A high throughput DNA assay capable of differentiating the normal and reduced saturate fatty acid alleles has been developed and can be used for accelerated molecular breeding. 相似文献127.
128.
Akbar SM Sharma HC Jayalakshmi SK Sreeramulu K 《Journal of bioenergetics and biomembranes》2012,44(1):233-241
The cotton bollworm, Helicoverpa armigera is a polyphagous pest in Asia, Africa, and the Mediterranean Europe. Salicylic acid (SA) and jasmonic acid (JA) are the cell
signaling molecules produced in response to insect attack in plants. The effect of these signaling molecules was investigated
on the oxidative phosphorylation and oxidative stress of H. armigera. SA significantly inhibited the state III and state IV respiration, respiratory control index (RCI), respiratory complexes
I and II, induced mitochondrial swelling, and cytochrome c release in vitro. Under in vivo conditions, SA induced state IV
respiration as well as oxidative stress in time- and dose-dependent manner, and also inhibited the larval growth. In contrast,
JA did not affect the mitochondrial respiration and oxidative stress. SA affected the growth and development of H. armigera, in addition to its function as signaling molecules involved in both local defense reactions at feeding sites and the induction
of systemic acquired resistance in plants. 相似文献
129.
J Roberto TRUJILLO Gilberto JARAMILLO-RANGEL Marta ORTEGA-MARTINEZ Augusto C PENALVA de OLIVEIRA Jose E VIDAL Joseph BRYANT Robert C GALLO 《Cell research》2005,(Z1)
INTRODUCTION AND NEUROEPIDEMIO- LOGY OF HIV/AIDS AIDS was first recognized as a new and distinct clini- cal entity in 1981 [1] and the HIV-1 as their casual agent in 1983 [2]. Since then, the HIV/AIDS epidemic has reached epidemic proportions with a total accumulative number of more than 60 million people, according to the Joint United Nations Programme on HIV/AIDS (UNAIDS) and WHO. The extensive spread of HIV-1 epidemics in Asia was not appreciated in the 1980s,… 相似文献
130.
siRNA, miRNA and HIV: promises and challenges 总被引:2,自引:0,他引:2
INTRODUCTION The recent discovery of small interfering RNA (siRNA) revealed an important role for small RNAs in regulating gene expression. First described in plants, as “post- trancriptional gene silencing” (PTGS) [1], RNA interfer- ence (RNAi) is a nucleic-acid based immune defense against viruses, transgenes and transposons [2]. Triggered by double-stranded RNA (dsRNA), RNAi leads to the se- quence specific degradation of a target mRNA [3]. In eukaryotic cells, long dsRN… 相似文献