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101.
本文以翅面正投影形状的特征参数为指标,对20科71种鳞翅目蛾类昆虫进行系统聚类。结果,粘虫Mythimna separata、小地老虎Agrotis ypsilon、稻纵卷叶螟Cnaphalocrocismedinalis等迁飞昆虫集中地归于一类,表明具有远距离迁飞行为的蛾类翅面几何形状相似,存在区别于其它种类的共同特征,即前翅较窄长,翅前缘较平直,外侧宽阔。这可能是适应远距离迁飞的特征。 相似文献
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Fen Zhou Yikui Zhang Ding Chen Zhitao Su Ling Jin Lei Wang Zhixiang Hu Zhisheng Ke Zongming Song 《PloS one》2014,9(10)
The degeneration of Müller cells has been recognized to involve in the pathogenesis of diabetic retinopathy. However, the mechanism is not yet clear. This study is to explore the potential role of Cyr61, a secreted signaling protein in extracellular matrix, in inducing human Müller cell degeneration in diabetic retinopathy (DR). Twenty patients with proliferative diabetic retinopathy (PDR) and twelve non-diabetic patients were recruited for this study. Vitreous fluid was collected during vitrectomy surgery for Cyr61 ELISA. Human Müller cell line MIO-M1 were cultured to be subconfluent, and then treated with glucose (0–20 mM) or Cyr61 (0–300 ng/ml). Cyr61 expression induced by increasing concentrations of glucose was evaluated by RT-qPCR and Western blot. Effects of Cyr61 on Müller cells viability, migration and apoptosis were observed by MTT assay, Transwell assay, and TUNEL assay. Vitreous Cyr61 levels were observed to be 8-fold higher in patients with PDR (3576.92±1574.58 pg/mL), compared with non-diabetic controls (436.14±130.69 pg/mL). Interestingly, the active PDR group was significantly higher than the quiescent PDR group (P<0.01). In retinal Müller cells culture, high glucose significantly and dose-dependently elevated Cyr61 expression at both mRNA and protein levels. Cyr61 at high concentrations dose-dependently inhibited the viability and migration of Müller cells. TUNEL assay further revealed that high concentration of Cyr61 significantly promoted the cell apoptosis. In conclusion, these findings demonstrated for the first time that the expression of Cyr61 was elevated by high glucose in Müller cells, and Cyr61 inhibited cell viability and migration while induced apoptosis, suggesting the potential role of Cyr61 in Müller cell degeneration. The elevated Cyr61 levels in vitreous fluid of PDR patients further support its role in diabetic retinopathy (DR). 相似文献
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Zhitao Niu Zhenyu Hou Mengting Wang Meirong Ye Benhou Zhang Qingyun Xue Wei Liu Xiaoyu Ding 《Ecology and evolution》2020,10(12):5332-5342
Comparative plastomics approaches have been used to identify available molecular markers for different taxonomic level studies of orchid species. However, the adoption of such methods has been largely limited in phylogeographic studies. Therefore, in this study, Dendrobium huoshanense, an endangered species with extremely small populations, was used as a model system to test whether the comparative plastomic approaches could screen available molecular markers for the phylogeographic study. We sequenced two more plastomes of D. huoshanense and compared them with our previously published one. A total of 27 mutational hotspot regions and six polymorphic cpSSRs have been screened for the phylogeographic studies of D. huoshanense. The cpDNA haplotype data revealed that the existence of haplotype distribution center was located in Dabieshan Mts. (Huoshan). The genetic diversity and phylogenetic analyses showed that the populations of D. huoshanense have been isolated and evolved independently for long period. On the contrary, based on cpSSR data, the genetic structure analysis revealed a mixed structure among the populations in Anhui and Jiangxi province, which suggested that the hybridization or introgression events have occurred among the populations of D. huoshanense. These results indicated that human activities have played key roles in shaping the genetic diversity and distributional patterns of D. huoshanense. According to our results, both two markers showed a high resolution for the phylogeographic studies of D. huoshanense. Therefore, we put forth that comparative plastomic approaches could revealed available molecular markers for phylogeographic study, especially for the species with extremely small populations. 相似文献
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Tingyu Fan Rongmei Qu Qinghe Yu Bing Sun Xin Jiang Yuchao Yang Xiaolan Huang Zhitao Zhou Jun Ouyang Shizhen Zhong Jingxing Dai 《Journal of cellular and molecular medicine》2020,24(14):7968-7978
The mechanisms underlying the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) remain unclear. In the present study, we aimed to identify the key biological processes during osteogenic differentiation. To this end, we downloaded three microarray data sets from the Gene Expression Omnibus (GEO) database: GSE12266, GSE18043 and GSE37558. Differentially expressed genes (DEGs) were screened using the limma package, and enrichment analysis was performed. Protein‐protein interaction network (PPI) analysis and visualization analysis were performed with STRING and Cytoscape. A total of 240 DEGs were identified, including 147 up‐regulated genes and 93 down‐regulated genes. Functional enrichment and pathways of the present DEGs include extracellular matrix organization, ossification, cell division, spindle and microtubule. Functional enrichment analysis of 10 hub genes showed that these genes are mainly enriched in microtubule‐related biological changes, that is sister chromatid segregation, microtubule cytoskeleton organization involved in mitosis, and spindle microtubule. Moreover, immunofluorescence and Western blotting revealed dramatic quantitative and morphological changes in the microtubules during the osteogenic differentiation of human adipose‐derived stem cells. In summary, the present results provide novel insights into the microtubule‐ and cytoskeleton‐related biological process changes, identifying candidates for the further study of osteogenic differentiation of the mesenchymal stem cells. 相似文献
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Jing Lin Kyung-Chul Yoon Lili Zhang Zhitao Su Rong Lu Ping Ma Cintia S. De Paiva Stephen C. Pflugfelder De-Quan Li 《PloS one》2012,7(11)
Tissue engineering holds great promise for corneal transplantation to treat blinding diseases. This study was to explore the use of natural corneal stroma as an optimal substrate to construct a native like corneal equivalent. Human corneal epithelium was cultivated from donor limbal explants on corneal stromal discs prepared by FDA approved Horizon Epikeratome system. The morphology, phenotype, regenerative capacity and transplantation potential were evaluated by hematoxylin eosin and immunofluorescent staining, a wound healing model, and the xeno-transplantation of the corneal constructs to nude mice. An optically transparent and stratified epithelium was rapidly generated on donor corneal stromal substrate and displayed native-like morphology and structure. The cells were polygonal in the basal layer and became flattened in superficial layers. The epithelium displayed a phenotype similar to human corneal epithelium in vivo. The differentiation markers, keratin 3, involucrin and connexin 43, were expressed in full or superficial layers. Interestingly, certain basal cells were immunopositive to antibodies against limbal stem/progenitor cell markers ABCG2 and p63, which are usually negative in corneal epithelium in vivo. It suggests that this bioengineered corneal epithelium shared some characteristics of human limbal epithelium in vivo. This engineered epithelium was able to regenerate in 4 days following from a 4mm-diameter wound created by a filter paper soaked with 1 N NaOH. This corneal construct survived well after xeno-transplantation to the back of a nude mouse. The transplanted epithelium remained multilayer and became thicker with a phenotype similar to human corneal epithelium. Our findings demonstrate that natural corneal stroma is an optimal substrate for tissue bioengineering, and a native-like corneal construct has been created with epithelium containing limbal stem cells. This construct may have great potential for clinical use in corneal reconstruction. 相似文献
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Xuelian Li Wei Liu Jie Wang Dayang Zou Xuesong Wang Zhan Yang Zhitao Yin Qian Cui Wei Shang Huan Li Xiao Wei Jing Cui Zhongquan Wang Liuyu Huang Jing Yuan 《International journal for parasitology》2012,42(13-14):1119-1126
Trichinella spiralis is a tissue-dwelling nematode parasite. A loop-mediated isothermal amplification (LAMP) assay was developed and validated for the sensitive and rapid detection of T. spiralis larvae in muscle samples. Sixteen sets of primers were designed to recognise distinct sequences of a conserved gene, a 1.6 kb repetitive element of the Trichinella genome. One set of primers was selected as the most appropriate for rapid detection. The specificity and sensitivity of the primers in LAMP reactions for T. spiralis larvae and muscle samples of mice infected with T. spiralis were determined. Another 10 heterologous parasites were selected for specificity assays. The results showed that target DNA was amplified and visualised by monitoring turbidity and adding calcein detection methods within 70 min at an isothermal temperature of 63 °C. The sensitivity of LAMP with the detection limit of 362 fg/μl was >10 times higher than that for PCR. The designed primers had a good specificity. No cross-reactivity was found with the DNA of any other parasites. The assay was able to detect T. spiralis in all mouse muscle samples infected with 10 T. spiralis larvae on day 20 p.i. We believe this is the first report regarding the application of the LAMP assay for detection of T. spiralis larvae in muscle samples from experimentally infected mice. This method demonstrates a potentially valuable means for the direct detection of T. spiralis larvae in meat inspection. 相似文献
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