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91.
LBX2-AS1 is a long non-coding RNA that facilitates the development of gastrointestinal cancers and lung cancer, but its participation in ovarian cancer development remained uninvestigated. Clinical data retrieved from TCGA ovarian cancer database and the clinography of 60 ovarian cancer patients who received anti-cancer treatment in our facility were analysed. The overall cell growth, colony formation, migration, invasion, apoptosis and tumour formation on nude mice of ovarian cancer cells were evaluated before and after lentiviral-based LBX2-AS1 knockdown. ENCORI platform was used to explore LBX2-AS1-interacting microRNAs and target genes of the candidate microRNAs. Luciferase reporter gene assay and RNA pulldown assay were used to verify the putative miRNA-RNA interactions. Ovarian cancer tissue specimens showed significant higher LBX2-AS1 expression levels that non-cancerous counterparts. High expression level of LBX2-AS1 was significantly associated with reduced overall survival of patients. LBX2-AS1 knockdown significantly down-regulated the cell growth, colony formation, migration, invasion and tumour formation capacity of ovarian cancer cells and increased their apoptosis in vitro. LBX2-AS1 interacts with and thus inhibits the function of miR-455-5p and miR-491-5p, both of which restrained the expression of E2F2 gene in ovarian cancer cells via mRNA targeting. Transfection of miRNA inhibitors of these two miRNAs or forced expression of E2F2 counteracted the effect of LBX2-AS1 knockdown on ovarian cancer cells. LBX2-AS1 was a novel cancer-promoting lncRNA in ovarian cancer. This lncRNA increased the cell growth, survival, migration, invasion and tumour formation of ovarian cancer cells by inhibiting miR-455-5p and miR-491-5p, thus liberating the expression of E2F2 cancer-promoting gene.  相似文献   
92.
Three new eremophilane sesquiterpenes phomadecalins G−I ( 1 – 3 ) and two new benzene derivatives microdiplzenes A and B ( 12 and 13 ), together with nine known eremophilane sesquiterpenes ( 4 – 11 and 14 ) were isolated from an endophytic fungus, Microdiplodia sp. WGHS5. Their structures were elucidated by the interpretation of HR-ESI-MS and NMR data; meanwhile, the absolute configurations of new compounds were determined on the base of ECD calculations. All compounds were evaluated for the antimicrobial activities and antiproliferative effect on human gastric cancer cell lines (BGC-823).  相似文献   
93.
Yue  Maofeng  Shen  Hao  Ye  Wanhui  Li  Weihua  Chen  Jinfeng 《Biological invasions》2021,23(9):2913-2925

Winter low temperature disturbance in the southern subtropics has important effects on the weed community structure, but the role of uniquely low temperatures in biological invasions is unclear. Here, we examined the competitive effects of an invasive plant, Bidens pilosa L., and its native congener, Bidens biternata (Lour.) Merr. et Sherff, during high and low temperature seasons to determine whether low temperatures promote the competitiveness of B. pilosa in the southern subtropics of China. The growth and physiological responses of the two Bidens species to low (10/5 °C) and optimum (30/25 °C) temperatures were examined to determine how the invasive B. pilosa responds to low temperature stress. Our results showed that the competitive balance index values of B. pilosa in low temperature seasons were significantly higher than those in high temperature seasons, which implied that low temperatures may be more beneficial to the competitiveness of B. pilosa than high temperatures in the southern subtropics. The smaller decline in the relative growth rate and the photosynthetic ability of B. pilosa compared with B. biternata under low temperature stress indicated that the former was less negatively affected by low temperature than the latter. A higher DPPH· (1.1-diphenyl-2-picrylhy-drazyl) scavenging rate and greater heat-stable protein content in B. pilosa under low temperatures might help the invasive plant to maintain more effective physiological functions and thus a higher growth rate. Overall, the uniquely low temperature in the southern subtropics of China is expected to promote the invasiveness of the exotic B. pilosa.

  相似文献   
94.
96序列相似的家庭成员A和B(family with sequence similarity 96 member A and B,FAM96A和FAM96B)是属于MIP18(MMS19-interacting protein of 18 kD)家族的2个高度保守的同源蛋白,MIP18是与有丝分裂纺锤体相关的MMDX(MMS19-MIP18-XPD)复合体的亚基。研究表明,FAM96A和FAM96B在人胃肠道间质瘤、结肠癌、肝癌、胃癌和乳腺癌等多种肿瘤组织中的表达显著降低,提示其可能是作为潜在的抑癌基因参与肿瘤的发生发展,但目前关于FAM96A和FAM96B在肿瘤发生发展过程中的作用机理并不十分清楚。此外,研究发现FAM96A和FAM96B可通过与其他不同的蛋白质相互作用在体内发挥多种不同的功能。因此,就目前对于FAM96A和FAM96B结构和功能的研究所取得的进展进行了回顾与总结,并对其在肿瘤发生发展中的分子机制和相互作用蛋白鉴定的研究前景进行了展望,以期为临床上将FAM96A和FAM96B作为新的肿瘤诊断标志物和治疗靶点奠定基础,并为揭示二者在体内更多的新功能提供依据。  相似文献   
95.
Vertebrate-type steroids, such as progesterone, have been identified in crustaceans. The physiological activity of progesterone during vitellogenesis is still not well understood. In this study, progesterone levels in the female mud crab, Scylla paramamosain, were determined by enzyme-linked immunosorbent assay. Peak levels of progesterone were detected during the previtellogenic stage in the hemolymph, ovary, and hepatopancreas, whereas the progesterone level decreased significantly in vitellogenic stage I. During vitellogenic stage II, progesterone levels rose again in the hemolymph and ovary, but continued to decrease in the hepatopancreas. By using western blotting, progesterone receptor (PR), with an apparent molecular weight of 70 kDa, was identified in the ovary during both vitellogenic stages I and II. By means of immunohistochemistry, PR was detected mainly in the follicle cells during vitellogenic stage I and in the nuclei of oocytes in vitellogenic stage II. Our results strongly suggest that progesterone promotes vitellogenesis in the mud crab, S. paramamosain via a classical genomic mechanism.  相似文献   
96.
Abstract

This paper describes a systematic investigation on the hemodynamic environment in a patient-specific AAA with tortuous common iliac artery(CIA) and external iliac artery (EIA). 3D reconstructions from CT scans and subsequent computational simulation are carried out. It is found out that the Newtonian and non-Newtonian models have very similar flow field and WSS distribution. More importantly, it is revealed that the torturous CIA maintained its helical flow. It is concluded that the assumption of Newtonian blood is adequate in capturing the intra-aneurysmal hemodynamics. Moreover, it is speculated that the physiological spiral flow protects the twisted CIA from the thrombosis formation.  相似文献   
97.
In 2007, the Chinese State Food and Drug Administration (SFDA) implemented a management system for lot release of all plasma-derived products. Since then, there have been only a few systematic studies of the blood supply, which is a concern when considering the small amount of plasma collected per capita (approximately 3 L/1000 people). As a result, there may be a threat to the safety of the available blood supply. In this study, we examined the characteristics of the supply of Chinese plasma-derived products. We investigated the reports of lot-released biological products derived from all 8 national or regional regulatory authorities in China from 2007 to 2011. The market supply characteristics of Chinese plasma-derived products were analyzed by reviewing the changes in supply varieties, the batches of lot-released plasma-derived products and the actual supply. As a result, the national regulatory authorities can more accurately develop a specific understanding of the production and quality management information provided by Chinese plasma product manufacturers. The implementation of the lot release system further ensures the clinical validity of the plasma-derived products in China and improves the safety of using plasma-derived products. This work provides an assessment of the future Chinese market supply of plasma-derived products and can function as a theoretical basis for the establishment of hemovigilance.  相似文献   
98.
The possible protective effects of resveratrol (RVT) against cardiotoxicity were investigated in Wistar albino rats treated with saline, saline+doxorubicin (DOX; 20 mg/kg) or RVT (10 mg/kg)+DOX. Blood pressure and heart rate were recorded on the 1st week and on the 7th week, while cardiomyopathy was assessed using transthoracic echocardiography before the rats were decapitated. DOX-induced cardiotoxicity resulted in decreased blood pressure and heart rate, but lactate dehydrogenase, creatine phosphokinase, total cholesterol, triglyceride, aspartate aminotransferase and 8-OHdG levels were increased in plasma. Moreover, DOX caused a significant decrease in plasma total antioxidant capacity along with a reduction in cardiac superoxide dismutase, catalase and Na+,K+-ATPase activities and glutathione contents, while malondialdehyde, myelopreoxidase activity and the generation of reactive oxygen species were increased in the cardiac tissue. On the other hand, RVT markedly ameliorated the severity of cardiac dysfunction, while all oxidant responses were prevented; implicating that RVT may be of therapeutic use in preventing oxidative stress due to DOX toxicity.  相似文献   
99.
100.
Wheat-Dasypyrum villosum translocated chromosomes T6V#2S?6AL and T6V#4S?6DL are known to confer excellent resistance to wheat powdery mildew (PM). However, it is difficult to distinguish the two sources of PM resistance genes through multi-pathotype testing because to date no virulence for them has been found. To reveal the relationship between the PM resistance genes from the two translocations, the sequence of the Stpk-V gene, a key member of powdery mildew resistance locus Pm21, was used as a reference to isolate homologous genes from a D. villosum accession No.1026 and its derivatives 6V#4(6D) disomic substitution (DS) line RW15 and T6V#4S?6DL translocation line Pm97033. Two genes Stpk-V2 and Stpk-V3 were cloned from No.1026. Sequence alignment showed that Stpk-V2 and Stpk-V3 shared 98.2 % and 96.2 % of their DNA and 99.3 % and 100 % of their amino acids in identity with Stpk-V. Compared with Stpk-V, a 22-bp direct sequence repeat and a miniature inverted-repeat transposable element (MITE) were found in the intron 4 of Stpk-V2 and Stpk-V3, respectively. However, Stpk-V2 was not present in DS line RW15 and translocation line Pm97033 based on the PCR result, indicating that Stpk-V2 did not contribute to the PM resistance of RW15 and Pm97033. In the promoter region, a 78-bp insertion was found not only in Stpk-V2 and Stpk-V3, but also in its orthologous gene Stpk-A of wheat. In addition, there was a 17 bp/8 bp deletion/insertion in the putative promoter of Stpk-V3 in comparison with that of Stpk-V/Stpk-V2. Real-time quantitative RT-PCR analysis indicated that the expression levels of Stpk-V and Stpk-V3 genes in the translocation lines were induced by the pathogen, but Stpk-V had a higher expression level than Stpk-V3 at 12 h after inoculation with Bgt. The diversity of Stpk-V gene will help to explore new resistance genes to PM in D. villosum for wheat breeding.  相似文献   
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