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761.
Lee SW Won JY Lee HY Lee HJ Youn SW Lee JY Cho CH Cho HJ Oh S Chae IH Kim HS 《Molecular medicine (Cambridge, Mass.)》2011,17(9-10):1095-1106
Early reperfusion after myocardial ischemia that is essential for tissue salvage also causes myocardial and vascular injury. Cardioprotection during reperfusion therapy is an essential aspect of treating myocardial infarction. Angiopoietin-1 is an endothelial-specific angiogenic factor. The potential effects of angiopoietin-1 on cardiomyocytes and vascular cells undergoing reperfusion have not been investigated. We propose a protective mechanism whereby angiopoietin-1 increases the integrity of the endothelial lining and exerts a direct survival effect on cardiomyocytes under myocardial ischemia followed by reperfusion. First, we found that angiopoietin-1 prevents vascular leakage through regulating vascular endothelial (VE)-cadherin phosphorylation. The membrane expression of VE-cadherin was markedly decreased on hypoxia/reoxygenation but was restored by angiopoietin-1 treatment. Interestingly, these effects were mediated by the facilitated binding between SH2 domain-containing tyrosine phosphatase (SHP2) or receptor protein tyrosine phosphatase μ (PTPμ) and VE-cadherin, leading to dephosphorylation of VE-cadherin. siRNA against SHP2 or PTPμ abolished the effect of angiopoietin-1 on VE-cadherin dephosphorylation and thereby decreased levels of membrane-localized VE-cadherin. Second, we found that angiopoietin-1 prevented cardiomyocyte death, although cardiomyocytes lack the angiopoietin-1 receptor Tie2. Angiopoietin-1 increased cardiomyocyte survival through integrin-β1-mediated extracellular signal-regulated kinase (ERK) phosphorylation, which inhibited caspase-9 through phosphorylation at Thr12? and subsequently reduced active caspase-3. Neutralizing antibody against integrin-β1 blocked these protective effects. In a mouse myocardial ischemia/reperfusion model, angiopoietin-1 enhanced cardiac function and reduction in left ventricular-end systolic dimension (LV-ESD) and left ventricular-end diastolic dimension (LV-EDD) with an increase in ejection fraction (EF) and fractional shortening (FS). Our findings suggest the novel cardioprotective mechanisms of angiopoietin-1 that are achieved by reducing both vascular leakage and cardiomyocyte death after ischemia/reperfusion injury. 相似文献
762.
763.
X.?NirmalaEmail author S.?R.?Olson T.?C.?Holler K.?H.?Cho A.?M.?Handler 《BioControl》2011,56(3):333-340
Field population surveillance of a targeted insect pest species is critical in evaluating management programs such as the
sterile insect technique. Fluorescent powder dyes currently used to distinguish released tephritids from the field population
are not optimal in terms of reliability and human health issues. Genetically transformed tephritid species present the possibility
of using fluorescent transgenes for marking. Here we studied the stability of DsRed fluorescence in transgenic flies maintained
in aqueous torula yeast borax and propylene glycol. DsRed was stable in both solutions for three weeks by visual microscopic
observations and could be used to unambiguously distinguish them from non-fluorescent wild type flies. To compensate for any
potential ambiguity in visual identification a diagnostic PCR was developed that could specifically amplify the exotic heterologous
marker gene. Therefore, the use of sterile transgenic insect strains carrying stably integrated fluorescent protein marker
genes in biologically-based control programs could greatly improve released fly identification in pest management programs. 相似文献
764.
The complete mitochondrial genome (JN415127) was sequenced and annotated newly from an individual of Hynobius yangi populations which were collected in Ulju-gun, Korea. The total length of the H. yangi genome is 16,403 bp, with a total base composition of 33.5% A, 32.3% T, 20.5% C, and 13.6% G. 相似文献
765.
We explored the relationship between epistemological beliefs and nature of science in a college biology course. One hundred
thirty-three college students participated in the research. Exploratory factor analysis with 29 Nature of Science (NOS) items
yielded three aspects of NOS: empirical, tentative, and sociocultural nature of scientific knowledge. Pearson r correlations suggested that students who have immature epistemological beliefs are more likely to also have immature beliefs
of nature of science. In addition, students’ epistemological beliefs significantly correlate with their conceptual change
but their beliefs about nature of science did not. The research is significant in that it provides empirical evidence explaining
the relationship between students’ epistemological beliefs and nature of science as well as the relationships between epistemological
beliefs and conceptual change in evolution theory. 相似文献
766.
Yang JJ Cho LY Ma SH Ko KP Shin A Choi BY Han DS Song KS Kim YS Chang SH Shin HR Kang D Yoo KY Park SK 《PloS one》2011,6(6):e21155
Background
CagA cellular interaction via activation of the ERK signaling pathway may be a starting point in the development of gastric cancer. This study aimed to evaluate whether genes involved in ERK downstream signaling pathways activated by CagA are susceptible genetic markers for gastric cancer.Methods
In the discovery phase, a total of 580 SNPs within +/−5 kbp of 30 candidate genes were genotyped to examine an association with gastric cancer risk in the Korean Multi-center Cancer Cohort (100 incident gastric cancer case-control sets). The most significant SNPs (raw or permutated p value<0.02) identified in the discovery analysis were re-evaluated in the extension phase using unconditional logistic regression model (400 gastric cancer case-control sets). Combined analyses including pooled- and meta-analysis were conducted to summarize all the results.Results
24 SNPs in eight genes (ERK, Dock180, C3G, Rap1, Src, CrkL, Mek and Crk) were significantly associated with gastric cancer risk in the individual SNP analyses in the discovery phase (p<0.05). In the extension analyses, ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 showed marginally significant gene-dose effects for gastric cancer. Consistently, final combined analysis presented the SNPs as significantly associated with gastric cancer risk (OR = 1.56, [95% CI: 1.19–2.06], OR = 0.61, [95% CI: 0.43–0.87], OR = 0.59, [95% CI: 0.54–0.76], respectively).Conclusions
Our findings suggest that ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 are genetic determinants in gastric carcinogenesis. 相似文献767.
768.
Characterization of an alternative splicing by a NAGNAG splice acceptor site in the porcine KIT gene
Jae-Hwan Kim Tao Zhong In-Cheol Cho Hyun-Tae Lim Chae-Kyoung Yoo Byeong-Woo Kim Jun-Heon Lee Jin-Tae Jeon 《Genes & genomics.》2011,33(2):179-186
The KIT gene has been shown to have multiple functions in hematopoiesis, melanogenesis, and gametogenesis. In addition, mutations of this gene cause pigmentation disorders in humans and mice and are responsible for coat color differences in pigs. While characterizing polymorphisms in the porcine KIT gene, we detected alternative splicing (AS) of the NAGNAG splice acceptor site at the boundary of intron 4 and exon 5. This AS event generated the E and I isoforms, characterized by insertion or deletion, respectively, of CAG at the borders of coding sequence. AS patterns measured in tissue samples from two randomly selected animals did not identified any tissue-specific outcomes. Analysis of AS patterns using three breeds demonstrated that Landrace and Large White pigs expressed both the E and I isoforms. In contrast, a subset of specimens from Korean Native Pigs (KNP) yielded a single I isoform. Alignment of the sequence from several species revealed that the region between the branch point sequence (BPS) and 3′ acceptor site is conserved. However, it is appeared that the selection of either the proximal or distal splice site varied between species. To test the breed specificity the NAGNAG splice acceptor site, we constructed two lineages of minigenes from KNP and Landrace pigs harboring breed-specific mutations. The minigene splicing assay demonstrated that both types of minigenes expressed both the E and I isoforms in two host cell lines, and no differences were detected in the AS pattern between the two breeds. We conclude that the AS at the NAGNAG splice acceptor site on intron 4/exon 5 in the porcine KIT gene is the result of noise selection at the splice site by the splicing machinery. Therefore, this AS event in the porcine KIT gene is unlikely to have any relationship with the coat color variations of Landrace and KNP breeds. 相似文献
769.
770.
Kung Ahn Jin-Han Bae Kyu-Hwi Nam Chong-Eon Lee Kyung-Do Park Hak-Kyo Lee Byung-Wook Cho Heui-Soo Kim 《Genes & genomics.》2011,33(3):245-250
Quantitative analysis of horse gene expression profiles under diverse experimental conditions is limited by the lack of reliable reference genes for normalization of mRNA levels. Therefore, in this study, the expression of potential reference genes was compared between thoroughbred and Jeju native horse (Jeju pony). We compared the expression of nine genes by quantitative real-time RT-PCR in fourteen tissues between the two horse breeds and analyzed their stability using the geNorm and NormFinder programs. The data obtained in this study suggest that the UBB gene could serve as a reference gene in gene expression analysis of thoroughbred and Jeju native horses. 相似文献