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61.
The geographic distributions of Hylonycteris underwoodi and Thyroptera tricolor in Honduras have been established with specimens collected more than 50 years ago. Here, we describe the occurrence of these bat species captured in the historic city of Ciudad Blanca, Gracias a Dios in northeastern Honduras.  相似文献   
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Many experimental and computational studies have identified key protein coding genes in initiation and progression of esophageal squamous cell carcinoma (ESCC). However, the number of researches that tried to reveal the role of long non-coding RNAs (lncRNAs) in ESCC has been limited. LncRNAs are one of the important regulators of cancers which are transcribed dominantly in the genome and in various conditions. The main goal of this study was to use a systems biology approach to predict novel lncRNAs as well as protein coding genes associated with ESCC and assess their prognostic values. By using microarray expression data for mRNAs and lncRNAs from a large number of ESCC patients, we utilized “Weighted Gene Co-expression Network Analysis” (WGCNA) method to make a big coding-non-coding gene co-expression network, and discovered important functional modules. Gene set enrichment and pathway analysis revealed major biological processes and pathways involved in these modules. After selecting some protein coding genes involved in biological processes and pathways related to cancer, we used “LncTar”, a computational tool to predict potential interactions between these genes and lncRNAs. By combining interaction results with Pearson correlations, we introduced some novel lncRNAs with putative key regulatory roles in the network. Survival analysis with Kaplan-Meier estimator and Log-rank test statistic confirmed that most of the introduced genes are associated with poor prognosis in ESCC. Overall, our study reveals novel protein coding genes and lncRNAs associated with ESCC, along with their predicted interactions. Based on the promising results of survival analysis, these genes can be used as good estimators of patients' survival, or even can be analyzed further as new potential signatures or targets for the therapy of ESCC disease.  相似文献   
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Gastric cancer is a common malignant tumor. Studies from our laboratory or others have shown that long non-coding RNA (lncRNA) zinc finger antisense (ZFAS)1 often acts as an oncogene. However, the molecular underpinnings of how ZFAS1 regulates gastric cancer remain to be elucidated. Results showed that ZFAS1 expression was upregulated, and microRNA-200b-3p (miR-200b) expression was downregulated in gastric cancer tissues. MiR-200b overexpression suppressed the proliferation, cell cycle process, and Wnt/β-catenin signaling of gastric cancer cells. Subsequently, we identified miR-200b is a target of ZFAS1 and Wnt1 is a target of miR-200b. Furthermore, promotion of cancer malignant progression and activation of Wnt/β-catenin signaling induced by ZFAS1 was counteracted by increasing miR-200b expression. In vivo, ZFAS1 knockdown suppressed the tumorigenesis with the upregulated miR-200b and the inactive Wnt/β-catenin signaling. Summarily, we demonstrated a critical role of miR-200b in gastric cancer, and ZFAS1 can promote malignant progression through regulating miR-200b mediated Wnt/β-catenin signaling.  相似文献   
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Breast cancer (BC)-related mortality is associated with the potential metastatic properties of the primary breast tumors. The following study was conducted with the main focus on the effect of LINC00518 on the growth and metastasis of BC epithelial cells via the Wnt signaling pathway through regulation of the methylation of CDX2 gene. Initially, differentially expressed long intergenic non-protein coding RNAs (lincRNAs) related to BC were screened out in the Cancer Genome Atlas (TCGA) database, after which we detected the LINC00518 expression and localization in BC tissues and cells. Then the CDX2 positive expression and methylation level were identified. The targeting relationship of LINC00518 and CDX2, and binding methyltransferase in the promoter region were examined. BC epithelial cell proliferation, colony formation ability, invasion, migration and apoptosis were further evaluated. The lincRNA expression data related to BC downloaded from the TCGA database revealed that there was a high expression of LINC00518 in BC, and a negative correlation between LINC00518 and CDX2. In addition, LINC00518 promotes CDX2 methylation by recruiting DNA methyltransferase through activating the Wnt signaling pathway. The down-regulation of LINC00518 inhibited proliferation, invasion, migration, and EMT of BC epithelial cells while enhancing apoptosis. The inhibitory effects of LINC00518 down-regulation was reversed by CDX2 down-regulation. In conclusion, our findings revealed that down-regulation of LINC00518 might have the ability to suppress BC progression by up-regulating CDX2 expression through the reduction of methylation and blockade of the Wnt signaling pathway, resulting in the inhibition of proliferation and promotion of apoptosis of BC epithelial cells.  相似文献   
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Yang DS  Wang P  Yang XT  Wang K  Fu CF  Wang YF 《生理学报》1999,51(4):463-466
为探究授乳大鼠双侧下丘脑巨细胞催产素神经元同步化射乳反射爆发放电的中枢所中,我们采用双微电极细胞外记录技术,观察了选择性脑切割损毁后的大鼠双侧视上核内催们素神经元在仔鼠吸吮刺激下射乳反射爆发放电。结果显示:在腹侧这画以上横向民单侧中脑中部,不同能阻断双侧催产素神经元的同步化爆发放 单侧下丘脑中间内侧部横切则可阻断这种经爆发放电。这些结果表明;中脑中部至一丘脑中部这一脑区在双侧视上核内催产素神经元的  相似文献   
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We have surveyed 18 natural populations of Drosophila melanogaster for the presence of 23 retrotransposon-gene-association alleles (i.e., the presence of an LTR retrotransposon sequence in or within 1,000 bp of a gene) recently identified in the sequenced D. melanogaster genome. The identified associations were detected only in the D. melanogaster populations. The majority (61%) of the identified retrotransposon-gene associations were present only in the sequenced strain in which they were first identified. Thirty percent of the associations were detected in at least one of the natural populations, and 9% of the associations were detected in all of the D. melanogaster populations surveyed. Sequence analysis of an association allele present in all populations indicates that selection is a significant factor in the spread and/or maintenance of at least some of retroelement-gene associations in D. melanogaster.  相似文献   
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