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1.
Peng Wang Ronghua Luo Min Zhang Yaqing Wang Tianzhang Song Tingting Tao Zhongyu Li Lin Jin Hongyi Zheng Wenwen Chen Mengqian Zhao Yongtang Zheng Jianhua Qin 《Cell death & disease》2020,11(12)
COVID-19, caused by SARS-CoV-2, is an acute and rapidly developing pandemic, which leads to a global health crisis. SARS-CoV-2 primarily attacks human alveoli and causes severe lung infection and damage. To better understand the molecular basis of this disease, we sought to characterize the responses of alveolar epithelium and its adjacent microvascular endothelium to viral infection under a co-culture system. SARS-CoV-2 infection caused massive virus replication and dramatic organelles remodeling in alveolar epithelial cells, alone. While, viral infection affected endothelial cells in an indirect manner, which was mediated by infected alveolar epithelium. Proteomics analysis and TEM examinations showed viral infection caused global proteomic modulations and marked ultrastructural changes in both epithelial cells and endothelial cells under the co-culture system. In particular, viral infection elicited global protein changes and structural reorganizations across many sub-cellular compartments in epithelial cells. Among the affected organelles, mitochondrion seems to be a primary target organelle. Besides, according to EM and proteomic results, we identified Daurisoline, a potent autophagy inhibitor, could inhibit virus replication effectively in host cells. Collectively, our study revealed an unrecognized cross-talk between epithelium and endothelium, which contributed to alveolar–capillary injury during SARS-CoV-2 infection. These new findings will expand our understanding of COVID-19 and may also be helpful for targeted drug development.Subject terms: Mechanisms of disease, Viral infection 相似文献
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The effects of different light regimes on the survival, growth and morphology ofQuercus serrata seedlings were studied in canopies ofMiscanthus sinensis. The seedlings of various ages (0–3 yr) were grown in three light regimes: under a denseM. sinensis canopy (TG plot) receiving 2.5%–8.7% of full sunlight, under a relatively sparse canopy (SG plot) receiving 3.8%–16.1% of
light and in an adjacent open site (NG plot). There was a little difference in the survival ofQ. serrata seedlings among the three plots. Height and diameter of stem and total leaf area of the seedlings were significantly lower
in the shadier plots. However, the first (bottom) flush of the stem was significantly longer in the TG plot than in the NG
and SG plots. Total dry weights of individual 1- and 2-yr-oldQ. serrata seedlings in the TG plot were reduced to about one-twelfth of those in the NG plot. Although the relative proportion in dry
weight of each organ did not differ significantly among the plots, leaf area ratio, specific leaf area and stem height per
unit dry weight were significantly higher in shadier plots. The leaf area per unit stem height was increased considerably
in the sunnier plots. 相似文献
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人体小卫星DNA探针的制备 总被引:3,自引:2,他引:1
根据人体小卫星DNA核心顺序,化学合成长23碱基寡核苷酸探针,筛选人体基因组文库,旨在获得能用作遗传分析探针的小卫星顺序。结果得到15个含小卫星的阳性重组子。随机取其一(C_(35.9))作探针,试做群体分析。所有个体均可检出多条杂交带。其中某些带具有多态性。在一定检测条件下,检出的DNA图谱在有限的个体内具有个体特异性。结果表明筛选文库得到的小卫星顺序可用于小卫星多态性的检测。其它小卫星探针的筛选和应用性研究正在进行。 相似文献
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Cibacron blue T_3GA与溴化氰活化的Sepharose 4B偶联后,产生一种能有效地分离有机磷水解酶的吸附剂。用0.15mol/L MgCl_2溶液从黄杆菌P3—2细胞抽提出的粗酶液通过柱层析分离,即可得到纯化8倍、酶活性回收率为269.4%的纯酶制品。该酶制品用凝胶电泳测是均一的。 相似文献
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Effects of microsite light availability on the growth and survival of transplantedQuercus serrata Thunb. seedlings in aMiscanthus sinensis Anderss. grass canopy were investigated by a “plant's eye view” approach. Diffuse site factors, i.e., the fractional transmissions
of diffuse photosynthetic photon flux density, were estimated at 15 cm aboveground in 108 microsites where the seedlings grew.
Microsite diffuse site factors were significantly different between surviving and dead seedlings during the experiment period
from April to October (F[1,14]=10.9, P<0.01). Relative growth rate of dry weight for individual seedlings positively depended on the diffuse site factors
(r2=0.482, P<0.001 in May; r2=0.312, P<0.001 in October). Only 16 seedlings produced their second stem flush within the grass canopy. The ratio of height
to dry weight of the second stem flush was significantly higher for the seedlings grew in shady microsites than for those
in less shady microsites (r2=0,471, P<0.01 in May). This study suggests that the microsite heterogeneity of light availability is one of the important
factors affecting the establishment of tree seedlings in patchy grasslands. 相似文献