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981.
Weiliang Cai Bowen Wu Zhizhong Li Peiheng He Biao Wang Anlie Cai Xiping Zhang 《Journal of cellular biochemistry》2019,120(2):2015-2027
Long noncoding RNAs (lncRNAs) have been identified to have increasingly important roles in tumorigenesis, and they may serve as novel biomarkers for cancer therapy. Recent studies have demonstrated that lncRNA NBR2 (neighbor of BRCA1 gene 2), a novel identified lncRNA, is decreased in several cancers; however, the role of NBR2 in the development of osteosarcoma has not been elucidated. In our study, we found that NBR2 expression was downregulated in osteosarcoma tissues, and osteosarcoma cases with lower NBR2 expression exhibited a shorter overall survival time compared with those with higher NBR2 expression. NBR2 overexpression inhibited osteosarcoma cell proliferation, invasion, and migration but did not increase apoptosis. Furthermore, RNA-binding protein immunoprecipitation assays confirmed that NBR2 directly binds to Notch1 protein. Furthermore, overexpression of Notch1 in NBR2-overexpressing osteosarcoma cells reversed the effects of NBR2 on cell proliferation, invasion, migration, and epithelial-mesenchymal transition. The in vivo results showed that NBR2 overexpression inhibited tumor growth in nude mice that were inoculated with osteosarcoma cells. NBR2 overexpression also suppressed the messenger RNA (mRNA) expression of Notch1, N-cadherin, and vimentin and increased the mRNA expression of E-cadherin in the tumor tissues. These data indicated that NBR2 served as a tumor suppressor gene in osteosarcoma and inhibited osteosarcoma cell proliferation, invasion, and migration. The current study provides a novel insight and treatment strategy for osteosarcoma. 相似文献
982.
Movement of individuals influences individual reproductive success, fitness, genetic diversity and relationships among individuals within populations and gene exchange among populations. Competition between males or females for mating opportunities and/or local resources predicts a female bias in taxa with monogamous mating systems and a male-biased dispersal in polygynous species. In birds and mammals, the patterns of dispersal between sexes are well explored, while dispersal patterns in protandrous hermaphroditic fish species have not been studied. We collected 549 adult individuals of Asian seabass (Lates calcarifer) from four locations in the South China Sea. To assess the difference in patterns of dispersal between sexes, we genotyped all individuals with 18 microsatellites. Significant genetic differentiation was detected among and within sampling locations. The parameters of population structure (F(ST)), relatedness (r) and the mean assignment index (mAIC), in combination with data on tagging-recapture, supplied strong evidences for female-biased dispersal in the Asian seabass. This result contradicts our initial hypothesis of no sex difference in dispersal. We suggest that inbreeding avoidance of females, female mate choice under the condition of low mate competition among males, and male resource competition create a female-biased dispersal. The bigger body size of females may be a cause of the female-biased movement. Studies of dispersal using data from DNA markers and tagging-recapture in hermaphroditic fish species could enhance our understanding of patterns of dispersal in fish. 相似文献
983.
苔藓植物对青岛市大气重金属污染的生物监测作用 总被引:2,自引:0,他引:2
苔藓植物因具有独特的形态和生理特征, 对空气污染反应十分敏感, 已被广泛用于监测城市或地区的环境质量与变化。通过分析连续2年采自青岛市崂山区的苔藓植物体内重金属含量, 并与崂山土壤重金属含量相比较, 探讨苔藓植物对大气重金属污染物的积累和指示作用。结果表明, 苔藓植物体内重金属含量能够反映空气重金属污染程度和空气质量变化。在崂山广泛分布的毛尖紫萼藓(Grimmia pilifera)对空气中重金属Pb、Zn、Cu和Cd都有着很强的富集能力, 是一种很好的重金属污染指示植物。长叶鳞叶藓(Taxiphyllum taxirameum)、大灰藓(Hypnum plumaeforme)和深绿绢藓(Entodon luridus)在崂山分布较多, 对重金属的积累能力也较强, 可用来监测青岛大气重金属污染。该研究为评价青岛市空气重金属污染状况提供了一个有效的生物监测方法。 相似文献
984.
Ying Xia Yu Zhou Han Han Peng Li Wei Wei Nengxing Lin 《Journal of cellular physiology》2019,234(11):19592-19601
Melanoma contributes a lot to skin cancer-related deaths. lncRNAs are implicated in various diseases, including melanoma. lncRNA NEAT1 is frequently dysregulated and can play important roles in multiple cancers. Nevertheless, little has been studied about the function of NEAT1 in melanoma progression. In our present research, we displayed NEAT1 was overexpressed in melanoma cells. A series of functional assays showed that overexpression of NEAT1 promoted the proliferation, migration, and invasion of melanoma cells. By contrast, NEAT1 knockdown obviously restrained melanoma cell progression. Mechanistically, it was revealed that NEAT1 could directly bind with miR-495-3p, which led to a negative effect on miR-495-3p levels. In addition, miR-495-3p was significantly decreased in melanoma cells. Furthermore, E2F3 was postulated as the target of miR-495-3p and overexpression of this miR could suppress the levels of E2F3. Meanwhile, it was exhibited that melanoma cell proliferation, migration, and invasion induced by E2F3 silence was abrogated by miR-495-3p. Moreover, an in vivo xenograft nude mice model was established using A375 cells and it was indicated that NEAT1 promoted melanoma progression in vivo via regulating the miR-495-3p/E2F3 axis. In conclusion, we suggest that NEAT1 exerts an oncogenic effect on melanoma development via inhibition of miR-495-3p and induction of E2F3. NEAT1 might serve as a crucial prognostic biomarker of melanoma. 相似文献
985.
The accumulation of pigment in fiber related to proanthocyanidins synthesis for brown cotton 总被引:2,自引:0,他引:2
Tingchun Li Honghong Fan Zhengpeng Li Jun Wei Yi Lin Yongping Cai 《Acta Physiologiae Plantarum》2012,34(2):813-818
Brown cotton is a kind of naturally colored cotton. Because of less processing and little dying, it is more friendlier to environment than white cotton. For brown cotton, pigment accumulation in fiber is one of the most important characteristics. In this study, we selected a brown fiber line and a white fiber cultivar to determine the factor that affects the pigmentation in brown fiber. Accordingly, fibers were collected to verify the presence of PAs by p-dimethylaminocinnamaldehyde (DMACA) and toluidine blue O (TBO) staining. The PAs content and related genes expressions were determined. As a result, there were obvious differences on the aspect of PAs synthesis in fiber between white cotton and brown cotton. For white fiber, the PAs content reached maximum at 5 DPA, and then gradually decreased to zero. But for brown fiber, the PAs content was increased from 5 to 15 DPA stage, and reached the maximum at the 15 DPA stage, then gradually decreased from 15 to 40 DPA stage. On the contrary, in white cotton, PAs were synthesized in the whole developmental stage from 5 to 40 DPA. And PAs content in brown fiber were far more than that in white fiber, which may be the reason why the brown pigment accumulated in brown fiber. 相似文献
986.
To improve the nutritional value of chickpea food, selenium (Se)-rich chickpea sprouts were produced by germination of chickpea
seeds for 6 days at 28 centigrade in the presence of various concentrations of Na2SeO3 in germination solution. High concentrations of selenite were found to inhibit the growth of chickpea sprout and the biosynthesis
of isoflavones formononetin and biochanin A. However, chickpea sprouts could tolerate up to ∼50 mg/L of Na2SeO3, under which condition the product chickpea sprouts contained a high Se content (2.14 μg/g dry weight) and a moderate high
content of isoflavones (601.56 μg biochanin A/g dry weight and 578.11 μg formononetin/g dry weight). Se was incorporated in
chickpea sprout in the form of selenomethionine. Thus, Se-enriched chickpea sprouts may serve as a convenient dietary source
of Se and of isoflavones, including formononetin and biochanin A. 相似文献
987.
近来的研究表明,一定条件的盐胁迫可导致植物细胞程序性死亡。本文利用DNALaddering、石蜡切片原位检测以及染色体涂片原位检测,从组织、细胞以及DNA等多个方面对盐胁迫下的玉米、水稻和烟草根尖细胞死亡作了研究,形态特别是生化方面的证据表明盐胁迫诱导的植物细胞凋亡可能在植物界具有一定的普遍性。但各个物种之间有一定差异。本实验结果对盐胁迫下的植物生理机制提供了新的研究思路。同时,我们还对基于染色体制片和石蜡切片的原位检测方法进行了比较和讨论。我们认为,基于染色体制片的原位标记技术适合于定性和定量检测单个细胞的凋亡,具有一些石蜡切片所不可及的优点。 相似文献
988.
Jinhuang Chen Qinghua Xia Bin Jiang Weilong Chang Wenzheng Yuan Zhijun Ma Zhengyi Liu Xiaogang Shu 《PloS one》2015,10(12)
Objective
Many studies have indicated the prognostic and clinicopathological value of aldehyde dehydrogenase 1 (ALDH1) in colorectal cancer (CRC) patients still remains controversial. Thus we performed this study to clarify the relationship between high ALDH1 expression in CRC and its impact on survival and clinicopathological features.Methods
Publications for relevant studies in Pubmed, the Cochrane Library, Embase, and China National Knowledge Infrastructure (CNKI) through April 2015 were identified. Only articles describing ALDH1 antigen with immunohistochemistry in CRC were included. The software RevMan 5.1 was used to analyze the outcomes, including 5-year overall survival (OS), disease-free survival (DFS) and clinicopathological features.Results
9 studies with 1203 patients satisfying the criteria were included. The overall rate of high ALDH1 expression was 46.5% by immunohistochemical staining. High ALDH1 expression as an independent prognostic factor was significantly associated with the 5-year OS and DFS (OR = 0.42, 95%CI: 0.26–0.68, P = 0.0004; OR = 0.38, 95%CI: 0.24–0.59, P < 0.0001, respectively). High ALDH1 expression was highly correlated with the tumor (T) stage (T3 + T4 vs. T1 + T2; OR = 2.16, 95%CI: 1.09–4.28, P = 0.03), lymph node (N) stage (N1 + N2 vs. N0; OR = 1.8; 95%CI: 1.17–2.79, P = 0.008), and tumor differentiation (G3 vs. G1 + G2; OR = 1.88; 95%CI: 1.07–3.30, P = 0.03). However, high ALDH1 expression was not significantly correlated with the patient age (>60 years old vs. <60 years old; OR = 1.11, 95%CI: 0.63–1.94, P = 0.72).Conclusions
High ALDH1 expression indicates a poor prognosis in CRC patients. Moreover, high ALDH1 expression correlates with the T stage, N stage, and tumor differentiation, but not with age. 相似文献989.
Antitumor agents. Part 204: synthesis and biological evaluation of substituted 2-aryl quinazolinones
Xia Y Yang ZY Hour MJ Kuo SC Xia P Bastow KF Nakanishi Y Namrpoothiri P Hackl T Hamel E Lee HK 《Bioorganic & medicinal chemistry letters》2001,11(9):1193-1196
A series of 2',3',4',6,7-substituted 2-aryl quinazolinones were synthesized and evaluated for biological activity. Among them, 17 displayed significant growth inhibitory action against a panel of tumor cell lines. Compound 17 was also a potent inhibitor of tubulin polymerization. Compounds 8-10 displayed selective activity against P-gp-expressing epidermoid carcinoma of the asopharynx. 相似文献
990.
Noggin and bFGF cooperate to maintain the pluripotency of human embryonic stem cells in the absence of feeder layers 总被引:20,自引:0,他引:20
Wang G Zhang H Zhao Y Li J Cai J Wang P Meng S Feng J Miao C Ding M Li D Deng H 《Biochemical and biophysical research communications》2005,330(3):934-942
Human embryonic stem (hES) cells are typically maintained on mouse embryonic fibroblast (MEF) feeders or with MEF-conditioned medium. However, these xenosupport systems greatly limit the therapeutic applications of hES cells because of the risk of cross-transfer of animal pathogens. Here we showed that the bone morphogenetic protein antagonist noggin is critical in preventing differentiation of hES cells in culture. Furthermore, we found that the combination of noggin and basic fibroblast growth factor (bFGF) was sufficient to maintain the prolonged growth of hES cells while retaining all hES cell features. Since both noggin and bFGF are expressed in MEF, our findings suggest that they may be important factors secreted by MEF for maintaining undifferentiated pluripotent hES cells. Our data provide new insight into the mechanism how hES cell self-renewal is regulated. The newly developed feeder-free culture system will provide a more reliable alternative for future therapeutic applications of hES cells. 相似文献