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11.
LRG‐1 promotes fat graft survival through the RAB31‐mediated inhibition of hypoxia‐induced apoptosis
Chiakang Ho Danning Zheng Jiaming Sun Dongsheng Wen Shan Wu Li Yu Ya Gao Yifan Zhang Qingfeng Li 《Journal of cellular and molecular medicine》2022,26(11):3153
Autologous adipose tissue is an ideal soft tissue filling material, and its biocompatibility is better than that of artificial tissue substitutes, foreign bodies and heterogeneous materials. Although autologous fat transplantation has many advantages, the low retention rate of adipose tissue limits its clinical application. Here, we identified a secretory glycoprotein, leucine‐rich‐alpha‐2‐glycoprotein 1 (LRG‐1), that could promote fat graft survival through RAB31‐mediated inhibition of hypoxia‐induced apoptosis. We showed that LRG‐1 injection significantly increased the maintenance of fat volume and weight compared with the control. In addition, higher fat integrity, more viable adipocytes and fewer apoptotic cells were observed in the LRG‐1‐treated groups. Furthermore, we discovered that LRG‐1 could reduce the ADSC apoptosis induced by hypoxic conditions. The mechanism underlying the LRG‐1‐mediated suppression of the ADSC apoptosis induced by hypoxia was mediated by the upregulation of RAB31 expression. Using LRG‐1 for fat grafts may prove to be clinically successful for increasing the retention rate of transplanted fat. 相似文献
12.
描述在甘肃临夏盆地晚中新世地层中发现的貘属新种和政貘(Tapirus hezhengensis sp. nov.),它是貘属中已知最小的种之一。在基本特征上,临夏盆地的和政貘与现生貘已相当接近,前臼齿完全臼齿化,门齿、犬齿的数目和形态也与现生貘一致。东亚晚中新世缺少貘科化石的材料,和政貘的发现对中国第四纪貘类的来源提供了重要线索,显示中中新世起源于欧洲的真貘在晚中新世时期已扩散至东亚。貘类通常适应于潮湿的热带森林环境,但和政貘在华北三趾马动物群中的发现说明这类动物也能够生活于干旱的温带草原地区。 相似文献
13.
Yuhui Wen Yingcai Wang James D. Potter W. Glenn L. Kerrick 《Journal of molecular biology》2009,392(5):1158-103
The human cardiac troponin I (hcTnI) mutation R145W has been associated with restrictive cardiomyopathy. In this study, simultaneous measurements of ATPase activity and force in skinned papillary fibers from hcTnI R145W transgenic mice (Tg-R145W) were explored. Tg-R145W fibers showed an ∼ 13-16% increase in maximal Ca2+-activated force and ATPase activity compared to hcTnI wild-type transgenic mice. The force-generating cross-bridge turnover rate (g) and the energy cost (ATPase/force) were the same in all groups of fibers. Also, the Tg-R145W fibers showed a large increase in the Ca2+ sensitivity of both force development and ATPase. In intact fibers, the mutation caused prolonged force and intracellular [Ca2+] transients and increased time to peak force. Analysis of force and Ca2+ transients showed that there was a 40% increase in peak force in Tg-R145W muscles, which was likely due to the increased Ca2+ transient duration. The above cited results suggest that: (1) there would be an increase in resistance to ventricular filling during diastole resulting from the prolonged force and Ca2+ transients that would result in a decrease in ventricular filling (diastolic dysfunction); and (2) there would be a large (approximately 53%) increase in force during systole, which may help to partly compensate for diastolic dysfunction. These functional results help to explain the mechanisms by which these mutations give rise to a restrictive phenotype. 相似文献
14.
15.
Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells 总被引:7,自引:0,他引:7
Mao JW Wang LW Jacob T Sun XR Li H Zhu LY Li P Zhong P Nie SH Chen LX 《Cell research》2005,15(5):371-378
The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells. 相似文献
16.
Antitumor mechanism of Se-containing polysaccharide, a novel organic selenium compound 总被引:1,自引:0,他引:1
Dejing Shang Qiao Cui Yang Li Zhi Yu Lei Wen Yuan Zhao Jianing Zhang 《Frontiers of Biology in China》2009,4(3):248-253
Recent studies on the inhibition of tumor growth by Se-containing polysaccharide were reviewed. Meanwhile, the possible molecular
mechanisms of the inhibition of tumor cell growth through antioxidation, induction of tumor cell apoptosis, blockade of cell
cycle, and enhancement of immunity by Se-containing polysaccharide were proposed. In the end, the potential application of
Se-containing polysaccharide in the prevention and treatment of tumor was elucidated. 相似文献
17.
The aim of the present study is to investigate the expression of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30) and its correlation with matrix metalloproteinases-9 (MMP-9) in epithelial ovarian cancer (EOC). Ovary tissues were obtained from 39 female patients, including 30 cases of EOC and 9 cases of benign ovarian tumor. Four normal ovary tissues were used as control. Immunohistochemical staining was used to detect the expressions of GPR30 and MMP-9. Chi square test, Fisher's exact test and Spearman's rank correlation analysis were used for statistical analysis. The results showed that GPR30 overexpression rate in EOC cases was significantly higher than those in benign ovarian tumor and normal ovary cases. Whereas MMP-9 overexpression rate in EOC cases was significantly higher than that in normal ovary cases, without any difference to that in benign ovarian tumor cases. To demonstrate the relationship between GPR30 and clinicopathological variables of EOC, we further analyzed the pathology type, FIGO stage and age of patients sampled in our study. The analysis showed there were significant differences of GPR30 overexpression rate among various pathology types and different FIGO stages (P<0.05), and no significant difference of both GPR30 and MMP-9 among three age groups (P>0.05). Moreover, GPR30 expression was positively correlated with MMP-9 (r(s)=1.000, P=0.002). These results suggest that GPR30 may be involved in the invasion and metastasis of EOC, being a potential index of EOC early diagnosis and malignancy grade prediction. 相似文献
18.
To understand the seasonal migration of the anadromous Coilia nasus , we attempted to identify the parasites infecting C. nasus and determine their seasonal occurrence. From June 2007 to July 2008, a survey of 775 C. nasus individuals from the estuary of the Yangtze River and the coast of the East China Sea revealed more than 7,300 parasites associated with the gills and alimentary tracts of C. nasus . The following 6 helminth taxa were identified, i.e., the monogeneans Heteromazocraes lingmueni and Helciferus tenuis, the digenean Elytrophallus coiliae, the acanthocephalan Acanthosentis cheni , and larvae of the nematodes Anisakis simplex and Contracaecum sp., all of which are marine or brackish-water parasites. The absence of freshwater helminths suggested that the parasites acquired in freshwater may have been accidentally, and easily, lost by the time the fish had reached the estuary and coast. Contrary to seasonal occurrence of the parasites' life cycles, the lowest mean abundance and prevalence of H. lingmueni and A. cheni occurred in August, which suggested the immigration of C. nasus from freshwater to the Yangtze estuary, with lower parasite burdens. The highest mean abundance and prevalence of the nematodes A. simplex and Contracaecum sp. in May and June, and the lowest in August, indicated the arrival of the fish from the coast and the Yangtze River, to the estuary, respectively. These findings suggested that a majority of the fish prepared for spawning migration in the estuary in spring and early summer and returned to the estuary after spawning in the lower and middle reaches of the Yangtze River in late summer. 相似文献
19.
Gao Y Yue W Zhang P Li L Xie X Yuan H Chen L Liu D Yan F Pei X 《Biochemical and biophysical research communications》2005,335(2):343-350
spindlin1, a novel human gene recently isolated by our laboratory, is highly homologous to mouse spindlin gene. In this study, we cloned cDNA full-length of this novel gene and send it to GenBank database as spindlin1 (Homo sapiens spindlin1) with Accession No. AF317228. In order to investigate the function of spindlin1, we studied further the subcellular localization of Spindlin1 protein and the effects of spindlin1 overexpression in NIH3T3 cells. The results showed that the fusion protein pEGFP-N1-spindlin1 was located in the nucleus and the C-terminal is correlated with nuclear localization of Spindlin1 protein. NIH3T3 cells which could stably express spindlin1 as a result of RT-PCR analysis compared with the control cells displayed a complete morphological change; made cell growth faster; and increased the percentage of cells in G2/M and S phase. Furthermore, overexpressed spindlin1 cells formed colonies in soft agar in vitro and formed tumors in nude mice. Our findings provide direct evidence that spindlin1 gene may contribute to tumorigenesis. 相似文献
20.