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991.
Our current research aimed to decipher the role and underlying mechanism with regard to miR-29b-3p involving in myocardial ischemia/reperfusion (I/R) injury. In the present study, cardiomyocyte H9c2 cell was used, and hypoxia/reoxygenation (H/R) model was established to mimic the myocardial I/R injury. The expressions of miR-29b-3p and pentraxin 3 (PTX3) were quantified deploying qRT-PCR and Western blot, respectively. The levels of LDH, TNF-α, IL-1β and IL-6 were detected to evaluate cardiomyocyte apoptosis and inflammatory response. Cardiomyocyte viability and apoptosis were examined employing CCK-8 assay and flow cytometry, respectively. Verification of the targeting relationship between miR-29b-3p and PTX3 was conducted using a dual-luciferase reporter gene assay. It was found that miR-29b-3p expression in H9c2 cells was up-regulated by H/R, and a remarkable down-regulation of PTX3 expression was demonstrated. MiR-29b-3p significantly promoted of release of inflammatory cytokines of H9c2 cells, and it also constrained the proliferation and promoted the apoptosis of H9c2 cells. Additionally, PTX3 was inhibited by miR-29b-3p at both mRNA and protein levels, and it was identified as a direct target of miR-29b-3p. PTX3 overexpression could reduce the inflammatory response, increase the viability of H9c2 cells, and inhibit apoptosis. Additionally, PTX3 counteracted the function of miR-29b-3p during the injury of H9c2 cells induced by H/R. In summary, miR-29b-3p was capable of aggravating the H/R injury of H9c2 cells by repressing the expression of PTX3.  相似文献   
992.
Journal of Applied Phycology - Farmed eucheumatoids are the top aquaculture commodity in the Philippines, contributing more than 60% of total national aquaculture production by volume. Despite...  相似文献   
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995.
Protein engineering through directed evolution is an effective way to obtain proteins with novel functions with the potential applications as tools for diagnosis or therapeutics. Many natural proteins have undergone directed evolution in vitro in the test tubes in the laboratories worldwide, resulting in the numerous protein variants with novel or enhanced functions. we constructed here an SH2 variant library by randomizing 8 variable residues in its phosphotyrosine (pTyr) binding pocket. Selection of this library by a pTyr peptide led to the identification of SH2 variants with enhanced affinities measured by EC50. Fluorescent polarization was then applied to quantify the binding affinities of the newly identified SH2 variants. As a result, three SH2 variants, named V3, V13 and V24, have comparable binding affinities with the previously identified SH2 triple‐mutant superbinder. Biolayer Interferometry assay was employed to disclose the kinetics of the binding of these SH2 superbinders to the phosphotyrosine peptide. The results indicated that all the SH2 superbinders have two‐orders increase of the dissociation rate when binding the pTyr peptide while there was no significant change in their associate rates. Intriguingly, though binding the pTyr peptide with comparable affinity with other SH2 superbinders, the V3 does not bind to the sTyr peptide. However, variant V13 and V24 have cross‐reactivity with both pTyr and sTyr peptides. The newly identified superbinders could be utilized as tools for the identification of pTyr‐containing proteins from tissues under different physiological or pathophysiological conditions and may have the potential in the therapeutics.  相似文献   
996.
Yang  Jing  Xun  HongWei  Niu  Lu  He  Hongli  Cheng  Yunqing  Zhong  Xiaofang  Zhao  Qianqian  Xing  Guojie  Liu  Jianfeng  Yang  Xiangdong 《Transgenic research》2021,30(5):675-686
Transgenic Research - Soybean seeds are an ideal host for the production of recombinant proteins because of their high content of proteins, long-term stability of seed proteins under ambient...  相似文献   
997.
Zhao  Shanshan  Cheng  Ming  Lin  Congyu  Liu  He  Wang  Zhengran  Zhang  Kai  Song  Simin  Yang  Qian 《Antonie van Leeuwenhoek》2021,114(11):1829-1839

During the investigation of exploring potential sources of novel species and natural bioactives, a novel actinomycete, designated strain HIT-DPA4T, was isolated from a soil sample, which was collected from Nanjing, Jiangsu Province, PR China and characterized using a polyphasic approach. On the basis of 16S rRNA gene sequence similarities and the result of phylogenetic analysis, strain HIT-DPA4T was most closely related to Streptomyces cyaneus CGMCC 4.1671 T, and shared the highest sequence similarity of 98.76%. In addition, the cell walls of the species HIT-DPA4T contained LL-diaminopimelic acid as the diagnostic diamino acid and the whole-cell hydrolysates were identified as glucose and ribose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and phosphatidylmonomethylethanolamine. MK-9(H6) and MK-9(H4) were predominant menaquinones; and C16:0, anteiso-C15:0 and C15:0 as major cellular fatty acids of the organism HIT-DPA4T. Gene Ontology database analysis and antiSMASH server predicted results displayed that strain HIT-DPA4T was a promising classification units, which has various types of functions and contains multiple biosynthetic gene clusters with the similarity more than 80%. Multilocus sequence analysis (MLSA) of five housekeeping genes (atpD, gyrB, recA, rpoB and trpB) illustrated that Streptomyces luteolifulvus formed a separate branch in the genus Streptomyces. However, a combination of low level of DNA-DNA relatedness and physiological properties indicated that strain HIT-DPA4T can be distinguished from its phylogenetically related species Streptomyces cyaneus CGMCC 4.1671 T. Moreover, gene synteny research could be further differed organism HIT-DPA4T from similarity species. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces luteolifulvus sp. nov. is proposed. The type strain is HIT-DPA4T (=?CGMCC 4.7558 T?=?TISTR 2751 T).

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998.
Cheng  Yuping  Zhu  Suting  Guo  Chaobo  Xie  Feilu  Jung  Dawoon  Li  Shengying  Zhang  Weiyan  He  Shan 《Antonie van Leeuwenhoek》2021,114(7):1033-1042
Antonie van Leeuwenhoek - A new bacterium was successfully isolated from a mangrove sediment sample in Haikou City, Hainan Province, China. The organism is a Gram-negative, rod-shaped, non-motile...  相似文献   
999.
Sui  Xin  He  Xiao-yan  Liu  Ning-hua  Dang  Yan-ru  Cha  Qian-qian  Sun  Mei-ling  Li  Chun-yang  Fu  Hui-hui  Song  Xiao-yan  Qin  Qi-long  Chen  Xiu-lan  Zhang  Yu-zhong  Su  Hai-nan  Zhang  Xi-ying 《Antonie van Leeuwenhoek》2021,114(7):947-955
Antonie van Leeuwenhoek - A novel Gram-negative, rod-shaped, aerobic, oxidase-positive and catalase-negative bacterium, designated strain SM1970T, was isolated from a seawater sample collected from...  相似文献   
1000.
He  Lingge  Zhang  Wenjie  Yang  Shuangyu  Meng  Wenting  Dou  Xia  Liu  Jianfeng  Liu  Yuanwei  Li  Haiyue  Jin  Tianbo 《Biochemical genetics》2021,59(3):697-713

The expression of IL-2RA and IL-2RB was correlated with breast cancer (BC) progression. However, there is no literature investigating the association of IL-2RA and IL-2RB polymorphisms with BC predisposition among Chinese Han Women. Seven SNPs in IL-2RA and IL-2RB were genotyped by Agena MassARRAY platform among 553 BC patients and 550 healthy controls. Odds ratios (OR) and 95% confidence interval (CI) adjusted for age were calculated for the effect of IL-2RA and IL-2RB variants on BC susceptibility. IL-2RA rs12722498 was a protective factor for BC occurrence (OR?=?0.70, p?=?0.019), especially in subjects with age?≤?52 years (OR?=?0.55, p?=?0.004). IL-2RA rs12569923 (OR?=?9.07, p?=?0.033), IL-2RB rs2281089 (OR?=?0.67, p?=?0.043) and rs9607418 (OR?=?0.59, p?=?0.012) were related to the incidence of estrogen receptor positive (ER?+) BC. IL-2RB rs3218264 (OR?=?1.38, p?=?0.010) and rs9607418 (OR?=?0.56, p?=?0.009) were associated with the risk of developing progesterone receptor positive (PR?+) BC. Rs2281089 (OR?=?1.54, p?=?0.012) and rs1573673 (OR?=?0.72, p?=?0.035) were correlated to Ki-67 level. Moreover, IL-2RB rs2281089 (OR?=?0.72, p?=?0.022) showed a reduced risk of BC metastasis, and IL-2RA rs12722498 (OR?=?0.54, p?=?0.030) had a lower frequency in BC patients with tumor size?>?2 cm. Our study identified the potential effect of genetic variations in IL-2RA and IL-2RB on BC susceptibility and/or BC clinicopathologic indicators among Chinese Han Women.

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