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51.
Background: WT161, as a selective HDAC6 inhibitor, has been shown to play anti-tumor effects on several kinds of cancers. The aim of the present study is to explore the roles of WT161 in osteosarcoma and its underlying mechanisms.Methods: The anti-proliferative effect of WT161 on osteosarcoma cells was examined using MTT assay and colony formation assay. Cell apoptosis was analyzed using flow cytometer. The synergistic effect was evaluated by isobologram analysis using CompuSyn software. The osteosarcoma xenograft models were established to evaluate the anti-proliferative effect of WT161 in vivo.Results: WT161 suppressed the cell growth and induced apoptosis of osteosarcoma cells in a dose- and time-dependent manner. Mechanistically, we found that WT161 treatment obviously increased the protein level of PTEN and decreased the phosphorylation level of protein kinase-B (AKT). More importantly, WT161 showed synergistic inhibition with 5-FU on osteosarcoma cells in vitro and in vivo.Conclusions: These results indicate that WT161 inhibits the growth of osteosarcoma through PTEN and has a synergistic efficiency with 5-FU.  相似文献   
52.
Chen  Jing-Jing  Shen  Jun-Xian  Yu  Zong-Hao  Pan  Chuan  Han  Fei  Zhu  Xiu-Ling  Xu  Hui  Xu  Rui-Ting  Wei  Tong-Yao  Lu  Ya-Ping 《Neurochemical research》2021,46(3):660-674
Neurochemical Research - Depression afflicts more than 300 million people worldwide, but there is currently no universally effective drug in clinical practice. In this study, chronic restraint...  相似文献   
53.
Xu  Furong  Wang  Hui  Tian  Ju  Xu  Haiyan 《Neurochemical research》2021,46(8):2192-2203

We aimed to illustrate the roles and molecular mechanisms of ID2-AS1 in parkinson’s disease (PD). Methods: qRT-PCR detected the expression of ID2-AS1. CCK-8, LDH release assays the effect of ID2-AS1 knockdown on PD cells. Flow cytometry and Western Blot were used to detect the effect of ID2-AS1 inhibition on PD cell apoptosis. ELISA analysis showed that ID2-AS1 inhibition can reduce the inflammation of PD cells. ROS activity assay showed that inhibiting ID2-AS1 attenuated the oxidative stress induced by 1-methy1-4-phenylpyridinium (MPP+). RNA binding protein immunoprecipitation assay showed that ID2-AS1 is mainly located in the cytoplasm. The luciferase reporter assay is used to verify the interaction. In our study, ID2-AS1 was concentration-dependently and time-dependently up-regulated in MPP+?-treated human neuroblastoma cell line SH-SY5Y. ID2-AS1 knockdown enhanced cell proliferation and decreased cell death in PD cells. Knockdown of ID2-AS1 attenuates MPP+?-induced cytotoxicity in SH-SY5Y cells. ID2-AS1 is a sponge of miR-199a-5p. IFNAR1 is a target of miR-199a-5p. Inhibition of miR-199a-5p and overexpression of IFNAR1 alleviate the inhibitory effect of ID2-AS1 knockdown on MPP+?triggered neuronal injury. Inhibition of miR-199a-5p and overexpression of IFNAR1 alleviate the inhibitory effect of ID2-AS1 knockdown on MPP+?-triggered JAK2/STAT1 activation. Overall, down-regulation of ID2-AS1 alleviated the neuronal injury in PD through regulating miR-199a-5p/IFNAR1/JAK2/STAT1 axis.

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54.
Vegetation History and Archaeobotany - In a continuous, perfectly stratified sedimentary sequence which was discovered under a large sandstone overhang in northern Bohemia, Czech Republic, we...  相似文献   
55.
聚羟基脂肪酸酯 (Polyhydroxyalkanoates,PHAs) 是一种具有优质生物相容性的可降解生物基材料,其理化性质优越,具备替代石油基塑料的潜力。P(3HB-co-LA) 是PHAs的一种,融合了聚乳酸 (Polylactic acid,PLA) 和聚3-羟基丁酸 (poly(3-hydroxybutyrate),P(3HB)) 共同的优点,具有更好的韧性和透明度。文中首先在大肠杆菌MG1655中通过质粒表达外源基因phaA、phaB、phaCm和pctth,发酵生产出乳酸含量为23.8 mol%的P(3HB-co-LA),在此基础上缺失dld基因得到菌株WXJ01-03,其合成的聚合物中乳酸组分含量提升至37.2 mol%。当硫酯酶基因ydiI和yciA基因继续被敲除后,生产的共聚物中乳酸组分进一步提升至42.3 mol%和41.1 mol%。最后将3个基因dld、yciA和ydiI同时缺失得到重组菌株WXJ03-03,并通过该重组菌株获得了乳酸组分含量为46.1 mol%的共聚物。通过比较不同碳源的发酵结果得知,木糖有利于提高共聚物中乳酸组分含量。上述实验结果表明,在木糖发酵中短链硫酯酶基因缺失阻碍了大肠杆菌胞内的LA-CoA被降解,可有效提高聚合物中乳酸组分的摩尔百分比。  相似文献   
56.
Oh  Byeong Seob  Kim  Ji-Sun  Ryu  Seoung Woo  Yu  Seung Yeob  Lee  Jung-Sook  Park  Seung-Hwan  Kang  Se Won  Lee  Jiyoung  Lee  Mi-Kyung  Lee  Kang Hyun  Jung  Won Yong  Jung  Hyunjung  Hur  Tai-Young  Kim  Hyeun Bum  Kim  Jae-Kyung  Lee  Ju-Hoon  Jeong  Jae-Ho  Lee  Ju Huck 《Antonie van Leeuwenhoek》2021,114(12):2091-2099

An obligately anaerobic, Gram-stain-positive, non-motile, non-spore-forming and rod-shaped strain AGMB00832T was isolated from swine faeces. Phylogenetic analysis based on the 16S rRNA gene, together with the housekeeping genes, gyrB and rpoD, revealed that strain AGMB00832T belonged to the genus Faecalicatena and was most closely related to Faecalicatena orotica KCTC 15331T. In biochemical analysis, strain AGMB00832T was shown to be negative for catalase, oxidase and urease. Furthermore, the isolate was positive for β-glucosidase, β-glucuronidase, glutamic acid decarboxylase, proline arylamidase, acid phosphatase and naphthol-AS-BI-phosphohydrolase. The major cellular fatty acids (>?10%) of the isolate were C14:0, C16:0 and C18:1ω11t DMA. Based on the whole genome sequence analysis, the DNA G?+?C content of strain AGMB00832T was 44.2 mol%, and the genome size and numbers of rRNA and tRNA genes were 5,175,159 bp, 11 and 53, respectively. The average nucleotide identity and digital DNA–DNA hybridization values between strain AGMB00832T and related strains were ≤?77.4 and 22.5%, respectively. Furthermore, the genome analysis revealed the presence of genes for alkaline shock protein 23 and cation/proton antiporters, which may facilitate growth of strain AGMB00832T in alkaline culture condition. On the basis of polyphasic taxonomic approach, strain AGMB00832T represents a novel species within the genus Faecalicatena, for which the name Faecalicatena faecalis sp. nov. is proposed. The type strain is AGMB00832T (=?KCTC 15946T?=?NBRC 114613T).

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57.
58.
The infection status with Clonorchis sinensis metacercariae (CsMc) was examined in freshwater fishes from Yongjeon-cheon (a branch of Nakdong-gang) located in Cheongsong-gun, Gyeongsangbuk-do, the Republic of Korea (Korea). A total of 750 fishes in 19 species were examined by the artificial digestion method for 2 years (2019 and 2020). CsMc were detected in 378 (51.4%) out of 735 fishes in 14 species (73.7%), and the infection intensity was 666 per fish infected. In 2019, CsMc were found in 172 (68.0%) out of 253 fishes in 10 species, and the infection intensity was 565 per fish infected. In 2020, CsMc were detected in 206 (62.2%) out of 331 fishes in 10 species, and the infection intensity was 751 per fish infected. The other zoonotic trematode, ie. Metagonimus spp., Centrocestus armatus, Echinostoma spp. and Clinostomum complanatum, metacercariae were also detected in fishes from the survey streams, but their endemicities were relatively low. Conclusively, it was first confirmed that CsMc are highly endemic in fishes from Yongjeon-cheon in Cheongsong-gun, Gyeongsangbuk-do, Korea.  相似文献   
59.
Xie  Linlin  Ju  Zhao  Zhong  Chaojie  Wu  Yingjun  Zan  Yuxing  Hou  Wei  Feng  Yong 《中国病毒学》2021,36(1):85-94
The human myxovirus resistance 2(Mx2/Mx B) protein, a member of interferon(IFN)-inducible dynamin-like large GTPases, restricts a number of virus infections. Inhibition of these viruses occurs at poorly-defined steps after viral entry and has a common requirement for Mx B oligomerization. However, the GTPase activity is essential for the anti-viral effects of Mx B against herpesviruses and HBV but not HIV-1. To understand the role of Mx B GTPase activity, including GTP binding and GTP hydrolysis, in restriction of HIV-1 infection, we genetically separated these two functions and evaluated their contributions to restriction. We found that both the GTP binding and hydrolysis function of Mx B involved in the restriction of HIV-1 replication. The GTPase activity of Mx B contributed to its nuclear location, interaction with nucleoporins(NUPs) and HIV-1 capsids. Furthermore, Mx B disrupted the association between NUPs and HIV-1 cores dependently upon its GTPase activity. The function of GTPase activity was therefore multi-faceted, led to fundamentally distinct mechanisms employed by wild-type Mx B and GTPase activity defective Mx B mutations to restrict HIV-1 replication.  相似文献   
60.
Zhu  Yun  Xu  Baoping  Li  Changchong  Chen  Zhimin  Cao  Ling  Fu  Zhou  Shang  Yunxiao  Chen  Aihuan  Deng  Li  Bao  Yixiao  Sun  Yun  Ning  Limin  Yu  Shuilian  Gu  Fang  Liu  Chunyan  Yin  Ju  Shen  Adong  Xie  Zhengde  Shen  Kunling 《中国病毒学》2021,36(6):1543-1553
Virologica Sinica - Community-acquired pneumonia (CAP) is one of the leading causes of morbidity and mortality in children worldwide. In this study, we aimed to describe the aetiology of viral...  相似文献   
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