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缺氧和高浓度葡萄糖对体外培养人视网膜色素上皮衍生因子表达的影响 被引量:31
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作者 姚毅 关明 +1 位作者 赵秀琴 黄一飞 《中华医学杂志》 CAS CSCD 北大核心 2003年第22期1989-1992,共4页
目的 探讨缺氧和高糖对体外培养的人视网膜色素上皮 (RPE)细胞血管内皮生长因子(VEGF)和色素上皮衍生因子 (PEDF)的影响。方法 我们通过实验性研究在氧正常或缺氧 (1%O2 )加或不加高浓度葡萄糖的条件下 ,培养的人RPE细胞 ,通过反转录... 目的 探讨缺氧和高糖对体外培养的人视网膜色素上皮 (RPE)细胞血管内皮生长因子(VEGF)和色素上皮衍生因子 (PEDF)的影响。方法 我们通过实验性研究在氧正常或缺氧 (1%O2 )加或不加高浓度葡萄糖的条件下 ,培养的人RPE细胞 ,通过反转录PCR和实时定量分析检测PEDF和VEGF的表达 ,使用Western印迹分析检测PEDF和VEGF蛋白水平。结果 缺氧情况下 ,VEGF表达和蛋白水平增加 (P =0 .0 0 1) ;缺氧加 2 5mmol/L葡萄糖后增加更加明显 (P <0 .0 0 1)。缺氧情况下PEDF表达水平与正常氧环境比较无统计学意义 (P =0 .2 5 1) ;但加葡萄糖后PEDFmRNA表达水平低于正常对照。结论 体外培养的人RPE细胞在缺氧条件下PEDF表达降低不明显 ,这提示缺氧间接影响体外RPE细胞的PEDF下调 ,高葡萄糖直接下调PEDF的表达 ,同时增加VEGF的表达 ,这可能支持体内高血糖是糖尿病最危险的“糖毒性”观点。 展开更多
关键词 缺氧 葡萄糖 体外培养 人视网膜色素 上皮衍生因子 表达 增殖性糖尿病视网膜病变
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Downregulation of orosomucoid 2 acts as a prognostic factor associated with cancer-promoting pathways in liver cancer 被引量:9
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作者 Han-Zhang Zhu Wei-Jiang Zhou +3 位作者 Ya-Feng Wan Ke Ge Jun Lu Chang-Ku Jia 《World Journal of Gastroenterology》 SCIE CAS 2020年第8期804-817,共14页
BACKGROUND Liver cancer has a high mortality and morbidity rate throughout the world.In clinical practice,the prognosis of liver cancer patients is poor,and the complex reasons contribute to treatment failures,includi... BACKGROUND Liver cancer has a high mortality and morbidity rate throughout the world.In clinical practice,the prognosis of liver cancer patients is poor,and the complex reasons contribute to treatment failures,including fibrosis,hepatitis viral infection,drug resistance and metastasis.Thus,screening novel prognostic biomarkers is of great importance for guiding liver cancer therapy.Orosomucoid genes(ORMs)encode acute phase plasma proteins,including orosomucoid 1(ORM1)and ORM2.Previous studies showed their upregulation upon inflammation,but the specific function of ORMs has not yet been determined,especially in the development of liver cancer.AIM To determine the expression of ORMs and their potential function in liver cancer.METHODS Analysis of the expression of ORMs in different human tissues was performed on data from the HPA RNA-seq normal tissues project.The expression ratio of ORMs was determined using the HCCDB database,including the ratio between liver cancer and other cancers,normal liver and other normal tissues,liver cancer and adjacent normal liver tissues.Analysis of ORM expression in different cancer types was performed using The Cancer Genome Atlas and TIMER database.The expression of ORMs in liver tumor tissues and adjacent normal tissues were further confirmed using Gene Expression Omnibus data,including GSE36376 and GSE14520.The 10-year overall survival(OS),progression-free survival(PFS)and relapse-free survival(RFS)rates between high and low ORM expression groups in liver cancer patients were determined using the Kaplan-Meier plotter tool.Gene Set Enrichment Analysis(GSEA)was employed to explore the ORM2-associated signaling network.Correlations between ORM2 expression and tumor purity or the infiltration level of macrophages in liver tumor tissues were determined using the TIMER database.The correlation between ORM2 gene levels,tumor-associated macrophage(TAM)markers(including CD68 and TGFβ1)and T cell immunosuppression(including CTLA4 and PD-1)in liver tumor tissues and liver GTEx was determi 展开更多
关键词 Orosomucoid gene Specific expression downregulation Prognostic factor Tumor promoter signaling Immune suppression
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细胞衰老与p16^(INK4a)的转录调控 被引量:6
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作者 薛丽香 李珺 +1 位作者 张宗玉 童坦君 《医学分子生物学杂志》 CAS CSCD 2006年第1期29-31,39,共4页
抑癌基因p16^(INK4a)可特异地抑制CDK4及CDK6,在抑制细胞生长、促进细胞衰老等方面发挥重要的生物学作用。由于p16^(INK4a)功能的重要性,近年来,针对p16^(INK4a)转录调控方面的研究取得了一系列进展,发现了一系列正性和负性调控元件和... 抑癌基因p16^(INK4a)可特异地抑制CDK4及CDK6,在抑制细胞生长、促进细胞衰老等方面发挥重要的生物学作用。由于p16^(INK4a)功能的重要性,近年来,针对p16^(INK4a)转录调控方面的研究取得了一系列进展,发现了一系列正性和负性调控元件和转录调控因子,如:E47、Id1、Jun B、Bmi-1、RREB等,为进一步认识细胞增殖规律以及衰老进程具有重要的理论意义。 展开更多
关键词 P16^INK4A 正转录调控 负转录调控 细胞衰老
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中药下调COX-2蛋白表达治疗慢性萎缩性胃炎的研究概况 被引量:7
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作者 韦德锋 韦维 +4 位作者 刘熙荣 卢山明 梁镫月 韦丽双 李月月 《中华中医药学刊》 CAS 北大核心 2018年第10期2349-2351,共3页
慢性萎缩性胃炎是消化系统常见病,目前认为其是胃癌前状态;伴肠上皮化生及不典型增生者更可能向癌变发展。COX-2蛋白的表达在胃黏膜炎性反应及癌变的过程中扮演着重要角色,研究发现中药能有效抑制其表达从而阻止萎缩性胃炎进一步向癌症... 慢性萎缩性胃炎是消化系统常见病,目前认为其是胃癌前状态;伴肠上皮化生及不典型增生者更可能向癌变发展。COX-2蛋白的表达在胃黏膜炎性反应及癌变的过程中扮演着重要角色,研究发现中药能有效抑制其表达从而阻止萎缩性胃炎进一步向癌症转化。对中药复方及单味中药抑制COX-2蛋白表达治疗慢性萎缩性胃炎的研究进行综述,以期指导临床与科学研究。 展开更多
关键词 慢性萎缩性胃炎 癌前病变 中药复方 中药活性成分 下调 COX-2蛋白
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猪伪狂犬病毒EP0蛋白拮抗宿主蛋白Spindlin1抗病毒作用的研究 被引量:3
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作者 赵鸿远 冯晗 +1 位作者 王迪 成温玉 《中国预防兽医学报》 CAS CSCD 北大核心 2023年第7期722-728,共7页
为了分析Spindlin1 (Spin1)蛋白对猪伪狂犬病毒(PRV)复制的影响,本研究利用GE Dharmacon siRNA网站设计3条Spin1 si RNA (siSpin1-376、siSpin1-537与si Spin1-654),将其以1∶1∶1的比例混合,以30 pmol的剂量转染PK-15细胞,转染后48 h感... 为了分析Spindlin1 (Spin1)蛋白对猪伪狂犬病毒(PRV)复制的影响,本研究利用GE Dharmacon siRNA网站设计3条Spin1 si RNA (siSpin1-376、siSpin1-537与si Spin1-654),将其以1∶1∶1的比例混合,以30 pmol的剂量转染PK-15细胞,转染后48 h感染PRV He N1株,并分别于感染后6 h、12 h、18 h和24 h收集细胞及上清样品,进行病毒的TCID50测定,结果显示,与对照组相比,感染后12 h,干扰Spin1的表达能够显著促进PRV在PK-15细胞中的增殖(P<0.05)。将PRV以MOI 0.1感染PK-15细胞后不同时间,利用western blot检测PRV感染对Spin1蛋白表达水平的影响,结果显示,与转染siRNA-NO的对照组相比,PRV感染后12 h细胞中的Spin1蛋白表达水平显著下降(P<0.05),其余时间段与对照组均无显著差异。为了阐明PRV拮抗Spin1抗病毒作用的分子机制,本研究分别构建PRV早期蛋白EP0与Spin1的真核表达质粒并分别经PCR及测序鉴定正确后共转染人胚胎肾细胞(HEK293FT),western blot结果显示,与单独转染Spin1表达质粒的细胞相比,共转染Spin1与EP0表达质粒细胞中Spin1的表达水平明显下调。进一步利用免疫共沉淀试验(Co-IP)分析二者的相互作用情况,结果显示,EP0与Spin1在共转染的细胞中存在相互作用。上述结果表明,PRV EP0蛋白能够通过与Spin1蛋白的相互作用下调其的表达。本研究发现了一个新的能够抑制PRV复制的宿主蛋白,并阐明了PRV拮抗宿主抗病毒因子的一种新机制,为揭示PRV的致病机理以及新型药物的研发提供参考。 展开更多
关键词 猪伪狂犬病毒 EP0蛋白 Spindlin1(Spin1) 下调
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Relationship between the downregulation of HLA class Ⅰ antigen and clinicopathological significance in gastric cancer 被引量:6
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作者 Yu-QingShen Jian-QiongZhang +5 位作者 Feng-QingMiao Jian-MinZhang QinJiang HaoChen Xiang-NianShan WeiXie 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第23期3628-3631,共4页
AIM:To discuss the expression of human leukocyte antigen (HLA) class Ⅰ antigens in gastric cancer and correlate these with pathologic type and TNM stage. METHODS: The expression of HLA class Ⅰ antigen was detected b... AIM:To discuss the expression of human leukocyte antigen (HLA) class Ⅰ antigens in gastric cancer and correlate these with pathologic type and TNM stage. METHODS: The expression of HLA class Ⅰ antigen was detected by immunohistochemistry in 185 specimens of gastric cancer, 20 gastric cancer specimens with lymphatic metastasis and 22 controls of normal gastric mucosa using four monoclonal antibodies. RESULTS: The expression of HLA class Ⅰ antigen (B/C locus) was significantly downregulated in gastric cancer and in lymphatic metastasis than that in normal gastric mucosa (x2=7.712, P<0.05). The expression of other HLA class Ⅰ antigens was also downregulated, but the change was slight. There was no relationship between the downregulation of HLA class Ⅰ antigen and that of β2m and LMP2. The expression of HLA class Ⅰ (B/C locus) was statistically correlated with pathologic stage in gastric adenocarcinoma (x2=4.164,P<0.05). CONCLUSION: The expression of HLA class Ⅰ antigen (B/C locus) was obviously downregulated in gastric cancer and in lymphatic metastasis. This abnormal expression would provide the tumor cells with a way to avoid immunological recognition. 展开更多
关键词 downregulation Gastric cancer
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Cognitive dysfunction in schizophrenia patients caused by downregulation of γ-aminobutyric acid receptor subunits
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作者 Xi Chen Ya-Nan Zhou +4 位作者 Xiao-Zi Lu Ren-Jiao Li Yi-Fan Xiong Xia Sheng Wei-Wei Zhu 《World Journal of Psychiatry》 SCIE 2024年第6期784-793,共10页
BACKGROUND The expression pattern of gamma aminobutyric acid(GABA)receptor subunits are commonly altered in patients with schizophrenia,which may lead to nerve excitation/inhibition problems,affecting cognition,emotio... BACKGROUND The expression pattern of gamma aminobutyric acid(GABA)receptor subunits are commonly altered in patients with schizophrenia,which may lead to nerve excitation/inhibition problems,affecting cognition,emotion,and behavior.AIM To explore GABA receptor expression and its relationship with schizophrenia and to provide insights into more effective treatments.METHODS This case-control study enrolled 126 patients with schizophrenia treated at our hospital and 126 healthy volunteers who underwent physical examinations at our hospital during the same period.The expression levels of the GABA receptor subunits were detected using 1H-magnetic resonance spectroscopy.The recognized cognitive battery tool,the MATRICS Consensus Cognitive Battery,was used to evaluate the scores for various dimensions of cognitive function.The correlation between GABA receptor subunit downregulation and schizophrenia was also analyzed.RESULTS Significant differences in GABA receptor subunit levels were found between the case and control groups(P<0.05).A significant difference was also found between the case and control groups in terms of cognitive function measures,including attention/alertness and learning ability(P<0.05).Specifically,as the expression levels of GABRA1(α1 subunit gene),GABRB2(β2 subunit gene),GABRD(δsubunit),and GABRE(εsubunit)decreased,the severity of the patients’condition increased gradually,indicating a positive correlation between the downregulation of these 4 receptor subunits and schizophrenia(P<0.05).However,the expression levels of GABRA5(α5 subunit gene)and GABRA6(α6 subunit gene)showed no significant correlation with schizophrenia(P>0.05).CONCLUSION Downregulation of the GABA receptor subunits is positively correlated with schizophrenia.In other words,when GABA receptor subunits are downregulated in patients,cognitive impairment becomes more severe. 展开更多
关键词 Cognitive function SCHIZOPHRENIA downregulation Gamma-aminobutyric acid receptor subunits CORRELATION
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Research Progress on the Pathogenesis of Acute Lung Injury(ALI)
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作者 Jincun LI Wenyu MA Gang LI 《Medicinal Plant》 2024年第4期122-128,共7页
In this review,the databases searched were PubMed and Web of Science.It is believed that the main causes of acute lung injury(ALI)and acute respiratory distress syndrome(ARDS)are inflammatory response disorders,excess... In this review,the databases searched were PubMed and Web of Science.It is believed that the main causes of acute lung injury(ALI)and acute respiratory distress syndrome(ARDS)are inflammatory response disorders,excessive oxidative stress,cell death,endoplasmic reticulum stress,coagulation dysfunction,and weakened aquaporin function. 展开更多
关键词 Acute lung injury(ALI) Pathogenesis Inflammatory responses Oxidative stress Cell death Endoplasmic reticulum stress COAGULOPATHY downregulation of aquaporin
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Photosynthetic and Molecular Markers of CO_2-mediated Photosynthetic Downregulation in Nodulated Alfalfa 被引量:3
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作者 Alvaro Sanz-Sez Gorka Erice +5 位作者 Iker Aranjuelo Ricardo Aroca Juan Manuel Ruíz-Lozano Jone Aguirreolea Juan Jos Irigoyen Manuel Sanchez-Diaz 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2013年第8期721-734,共14页
Elevated CO2 leads to a decrease in potential net photosynthesis in long-term experiments and thus to a reduction in potential growth. This process is known as photosynthetic downregulation. There is no agreement on t... Elevated CO2 leads to a decrease in potential net photosynthesis in long-term experiments and thus to a reduction in potential growth. This process is known as photosynthetic downregulation. There is no agreement on the definition of which parameters are the most sensitive for detecting CO2 acclimation. In order to investigate the most sensitive photosynthetic and molecular markers of CO2 acclimation, the effects of elevated CO2, and associated elevated temperature were analyzed in alfalfa plants inoculated with different Sinorhizobium meliloti strains. Plants (Medicago sativa L. cv. Aragon) were grown in summer or autumn in temperature gradient greenhouses (TGG). At the end of the experiment, all plants showed acclimation in both seasons, especially under elevated summer temperatures. This was probably due to the lower nitrogen (N) availability caused by decreased N2-fixation under higher temperatures. Photosynthesis measured at growth CO2 concentration, rubisco in vitro activity and maximum rate of carboxylation were the most sensitive parameters for detecting downregulation. Severe acclimation was also related with decreases in leaf nitrogen content associated with declines in rubisco content (large and small subunits) and activity that resulted in a drop in photosynthesis. Despite the sensitivity of rubisco content as a marker of acclimation, it was not coordinated with gene expression, possibly due to a lag between gene transcription and protein translation. 展开更多
关键词 Carbon dioxide Medicago sativa (alfalfa) photosynthetic downregulation RbcL and RbcS Sinorhizobium meliloti.
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miRNA与其靶mRNA的相互作用:绑定位点的质量与数量特征的整合计算分析(英文) 被引量:5
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作者 付聪 林魁 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2009年第5期608-615,共8页
miRNAs通过完全或不完全的碱基互补绑定到信使RNA(mRNA)上,通过抑制翻译或者直接导致mRNA降解的方式来调节靶基因的表达.为了研究miRNAs在转录水平上面的调控作用,两种人类基因组中组织特异的miRNAs(miR-1和miR-124)被转染到HeLa细胞中... miRNAs通过完全或不完全的碱基互补绑定到信使RNA(mRNA)上,通过抑制翻译或者直接导致mRNA降解的方式来调节靶基因的表达.为了研究miRNAs在转录水平上面的调控作用,两种人类基因组中组织特异的miRNAs(miR-1和miR-124)被转染到HeLa细胞中,微阵列(microarray)分析转染前后细胞中各基因mRNA表达水平变化情况的结果表明:动物基因组中靶基因与miRNAs不完全的碱基互补也会导致mRNA的直接降解.通过分析实验得到的mRNA表达水平变化数据,发现这相同miRNA的不同靶基因mRNA表达水平的下调倍数有着明显的差别,推测这些靶基因mRNA序列本身存在某些影响其受调节程度的因素.为此,提取和分析这些靶基因mRNA的序列特征,通过对这些序列特征与mRNA表达水平下调数据进行统计相关分析,最终发现,miRNA靶基因受调节的程度与以下几个因素相关联:mRNA序列中miRNA靶位点的个数,靶位点与miRNA序列碱基互补的程度,以及绑定后形成二级结构的稳定程度(即最低自由能的大小).在此基础上,初步建立起一个多因子作用下的miRNA靶基因mRNA表达水平下调程度模型,分析表明:该模型在一定程度上可以反映了部分序列特征对于miRNA靶基因mRNA表达水平下调程度的影响. 展开更多
关键词 MICRORNA 靶位点 靶mRNA 下调
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Loss of the vitamin D receptor in human breast and prostate cancers strongly induces cell apoptosis through downregulation of Wnt/β-catenin signaling 被引量:5
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作者 Yu Zheng Trupti Trivedi +9 位作者 Ruby CY Lin Colette Fong-Yee Rick Nolte Jeline Manibo Yunzhao Chen Musharraf Hossain Konstantin Horas Colin Dunstan Hong Zhou Markus J Seibel 《Bone Research》 SCIE CAS CSCD 2017年第3期195-206,共12页
Vitamin D co-regulates cell proliferation, differentiation and apoptosis in numerous tissues, including cancers. The known anti-proliferative and pro-apoptotic actions of the active metabolite of vitamin D, 1,25-dihyd... Vitamin D co-regulates cell proliferation, differentiation and apoptosis in numerous tissues, including cancers. The known anti-proliferative and pro-apoptotic actions of the active metabolite of vitamin D, 1,25-dihydroxy-vitamin D [1,25(OH)2D] are mediated through binding to the vitamin D receptor (VDR). Here, we report on the unexpected finding that stable knockdown of VDR expression in the human breast and prostate cancer cell lines, MDA-MB-231 and PC3, strongly induces cell apoptosis and inhibits cell proliferation in vitro. Implantation of these VDR knockdown cells into the mammary fat pad (MDA-MB-231), subcutaneously (PC3) or intra-tibially (both cell lines) in immune-incompetent nude mice resulted in reduced tumor growth associated with increased apoptosis and reduced cell proliferation compared with controls. These growth-retarding effects of VDR knockdown occur in the presence and absence of vitamin D and are independent of whether cells were grown in bone or soft tissues. Transcriptome analysis of VDR knockdown and non-target control cell lines demonstrated that loss of the VDR was associated with significant attenuation in the Wnt/0-catenin signaling pathway. In particular, cytoplasmic and nuclear β-catenin protein levels were reduced with a corresponding downregulation of downstream genes such as Axin2, Cyclin D1, interleukin-6 (IL-6), and IL-8. Stabilization of 0-catenin using the GSK-3β inhibitor BIO partly reversed the growth-retarding effects of VDR knockdown. Our results indicate that the unliganded VDR possesses hitherto unknown functions to promote breast and prostate cancer growth, which appear to be operational not only within but also outside the bone environment. These novel functions contrast with the known anti-proliferative nuclear actions of the liganded VDR and may represent targets for new diagnostic and therapeutic approaches in breast and prostate cancer. 展开更多
关键词 MDA Loss of the vitamin D receptor in human breast and prostate cancers strongly induces cell apoptosis through downregulation of Wnt catenin signaling VDR WNT
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不同剂量曲普瑞林降调节方案用于体外受精-胚胎移植的临床效果 被引量:5
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作者 单丹 赵军招 +2 位作者 吕杰强 应映芬 张帆 《浙江医学》 CAS 2017年第15期1258-1260,1264,共4页
目的探讨在体外受精-胚胎移植(IVF-ET)中不同剂量曲普瑞林降调节效果,探索最佳注射剂量,以寻找性价比最高的治疗方案。方法回顾性分析行黄体期长方案治疗的379个IVF-ET周期,采用不同剂量曲普瑞林降调节(0.60~1.00mg117例为A组,1.75~2.00... 目的探讨在体外受精-胚胎移植(IVF-ET)中不同剂量曲普瑞林降调节效果,探索最佳注射剂量,以寻找性价比最高的治疗方案。方法回顾性分析行黄体期长方案治疗的379个IVF-ET周期,采用不同剂量曲普瑞林降调节(0.60~1.00mg117例为A组,1.75~2.00mg 65例为B组,3.75mg 197例为C组),比较3组患者降调节后启动日、注射绒毛膜促性腺激素(HCG)日雌激素水平,子宫内膜厚度,促性腺激素(Gn)使用时间及总量,获卵数、成熟卵子率、正常受精率、卵裂率、第3天优胚率,种植率、临床妊娠率、流产率、重度卵巢过度刺激综合征(OHSS)发生率等。结果降调节后启动日C组促黄体生成素(LH)水平为(0.41±0.28)IU/L,分别低于A组(1.32±0.60)IU/L和B组(1.17±0.51)IU/L(均P<0.05);注射HCG日A组LH水平为(0.98±1.09)IU/L,分别高于B组(0.57±0.30)IU/L和C组(0.62±0.60)IU/L(均P<0.05);Gn使用天数为B组>C组>A组(均P<0.05);Gn使用总量3组比较差异无统计学意义(P>0.05)。B、C组成熟卵子率均高于A组(均P<0.05);B组第3天优胚率明显高于A组(P<0.05),与C组比较差异无统计学意义(P>0.05)。3组患者获卵数、正常受精率、卵裂率、种植率、临床妊娠率、流产率、重度OHSS发生率比较,差异均无统计学意义(均P>0.05)。结论全量曲普瑞林降调节在不增加Gn用量的前提下,种植率、临床妊娠率均良好,流产率、重度OHSS发生率均较低,是一种安全有效的降调节方法。 展开更多
关键词 降调节 促性腺激素释放激素激动剂 子宫内膜容受性 体外受精-胚胎移植
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NF-κB,a hot topic in biochemical and medical studies in China 被引量:2
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作者 WEI Yan State Key Laboratory of Brain and Cognitive Sciences,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 《Science China(Life Sciences)》 SCIE CAS 2010年第12期1485-1487,共3页
In 1986, nuclear factor (NF)-κB was first discovered in the laboratory of Nobel Prize laureate David Baltimore via its interaction with a sequence (5′-GGGACTTTCC-3′) in the immunoglobulin light-chain enhancer in B
关键词 NF-ΚB TRANSCRIPTION factor SIGNALING pathway UPREGULATION downregulation
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Downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid 被引量:3
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作者 María Josefa López Núez-Flores Jorge Gutirrez +3 位作者 Laura V.Gómez-Ros Esther Novo Uzal Mariana Sottomayor Alfonso Ros Barceló 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第2期244-251,共8页
Hypocotyl formation during the epigeal germination of seedlings is under strict hormonal regulation. In a 3 d old Zinnia elegans seedling system, gibberellic acid (GA3) exerts an opposite effect to that exerted by l... Hypocotyl formation during the epigeal germination of seedlings is under strict hormonal regulation. In a 3 d old Zinnia elegans seedling system, gibberellic acid (GA3) exerts an opposite effect to that exerted by light on hypocotyl photomorphogenesis because GAz promotes an etiolated-like growth with an inhibition of radial (secondary) growth. For this reason, the effect of GA3 on the basic peroxidase isoenzyme from Z. elegans (ZePrx), an enzyme involved in hypocotyl lignin biosynthesis, was studied. The results showed that GA3 reduces ZePrx activity, similarly to the way in which it reduces seedling secondary growth. This hormonal response is supported by the analysis of the ZePrx promoter, which contains four types of GA3-responsive cis.elements: the W Box/O2S; the Pyr Box; the GARE; and the Amy Box. Taken together, these results suggest that ZePrx is directly regulated by GA3, with this effect matching the inhibitory effect of GA on the hypocotyl secondary growth. 展开更多
关键词 GA downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid CIS FIGURE
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促性腺激素释放激素激动剂降调对垂体内外的影响 被引量:3
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作者 朱桂金 徐蓓 聂睿 《生殖医学杂志》 CAS 2011年第A01期3-7,43,共5页
降调是促激素下调自身的受体以调节靶组织对激素的反应性,是促激素调节其自身作用的机制之一。除受体的升调和降调外,促激素还可通过自分泌/旁分泌、激素的异质性来调节自身的作用。降调的机制是通过受体与调节亚单位G蛋白解耦联、受体... 降调是促激素下调自身的受体以调节靶组织对激素的反应性,是促激素调节其自身作用的机制之一。除受体的升调和降调外,促激素还可通过自分泌/旁分泌、激素的异质性来调节自身的作用。降调的机制是通过受体与调节亚单位G蛋白解耦联、受体内在化进入细胞、以及腺苷酸环化酶的调节和催化亚单位解耦联3种途径来实现的。降调对卵泡刺激素(FSH)和黄体生成素(LH)的直接作用是使40%~60%的FSH分泌受到抑制,而90%的LH分泌受到抑制,目的是抑制过早内源性LH峰。降调对FSH、LH旁分泌调节的作用需要通过FSH和LH发挥作用,旁分泌调节因子本身并没有促使卵泡发育的作用。由于类固醇激素的负反馈是通过下丘脑垂体发挥作用,而降调是在促性腺激素释放激素(GnRH)的受体水平,因此取消了类固醇激素正常的正负反馈。由于卵巢颗粒细胞、膜细胞、黄体细胞均有GnRH受体,理论上推测GnRH对卵巢可能有直接作用。动物实验及体外试验均提示GnRH对卵巢颗粒细胞有直接作用,体现在类固醇的合成和卵泡的发育两方面。因此,促性腺激素释放激素激动剂(GnRH-a)提高妊娠率的作用除了来自于抑制过早LH峰,降低过高LH的不利作用外,还可能来自GnRH-a对卵泡发育、卵母细胞成熟、子宫内膜的容受性等直接作用,但目前的研究方法尚无法证实。 展开更多
关键词 促性腺激素释放激素激动剂 降调 垂体 卵巢
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Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1 被引量:2
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作者 Yu Jin Zhen Liu +5 位作者 Zhenxia Li Hairui Li Cheng Zhu Ruomei Li Ting Zhou Bing Fang 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期396-409,共14页
Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected ... Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected potential regulatory mechanisms underlying OA and have concentrated on developing novel treatment strategies,the epigenetic control of OA remains unclear.Histone demethylase JMJD3 has been reported to mediate multiple physiological and pathological processes,including cell differentiation,proliferation,autophagy,and apoptosis.However,the regulation of JMJD3 in aberrant force-related OA and its mediatory effect on disease progression are still unknown.In this work,we confirmed the upregulation of JMJD3 in aberrant forceinduced cartilage injury in vitro and in vivo.Functionally,inhibition of JMJD3 by its inhibitor,GSK-J4,or downregulation of JMJD3 by adenovirus infection of sh-JMJD3 could alleviate the aberrant force-induced chondrocyte injury.Mechanistic investigation illustrated that aberrant force induces JMJD3 expression and then demethylates H3K27me3 at the NR4A1 promoter to promote its expression.Further experiments indicated that NR4A1 can regulate chondrocyte apoptosis,cartilage degeneration,extracellular matrix degradation,and inflammatory responses.In vivo,anterior cruciate ligament transection(ACLT)was performed to construct an OA model,and the therapeutic effect of GSK-J4 was validated.More importantly,we adopted a peptide-si RNA nanoplatform to deliver si-JMJD3 into articular cartilage,and the severity of joint degeneration was remarkably mitigated.Taken together,our findings demonstrated that JMJD3 is flow-responsive and epigenetically regulates OA progression.Our work provides evidences for JMJD3 inhibition as an innovative epigenetic therapy approach for joint diseases by utilizing p5RHH-si RNA nanocomplexes. 展开更多
关键词 Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1
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NKT cells in HIV-1 infection 被引量:2
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作者 Demin Li Xiao-Ning Xu 《Cell Research》 SCIE CAS CSCD 2008年第8期817-822,共6页
Natural killer T (NKT) cells are a unique T cell population that have important immunoregulatory functions and have been shown to be involved in host immunity against a range of microorganisms. It also emerges that ... Natural killer T (NKT) cells are a unique T cell population that have important immunoregulatory functions and have been shown to be involved in host immunity against a range of microorganisms. It also emerges that they might play a role in HIV-1 infection, and therefore be selectively depleted during the early stages of infection. Recent studies are reviewed regarding the dynamics of NKT depletion during HIV-1 infection and their recovery under highly active antiretroviral treatment (HAART). Possible mechanisms for these changes are proposed based on the recent developments in HIV pathogenesis. Further discussions are focused on HIV's disruption of NKT activation by downregulating CDld expression on antigen presentation cells (APC). HIV-1 protein Nefis found to play the major role by interrupting the intracellular trafficking of nascent and recycling CDld molecules. 展开更多
关键词 NKT cells HIV-1 CDId downregulation
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Loss of HER2 in breast cancer: biological mechanisms and technical pitfalls 被引量:1
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作者 Stefania Morganti Mariia Ivanova +6 位作者 Emanuela Ferraro Liliana Ascione Grazia Vivanet Giuseppina Bonizzi Giuseppe Curigliano Nicola Fusco Carmen Criscitiello 《Cancer Drug Resistance》 2022年第4期971-980,共10页
Loss of HER2 in previously HER2-positive breast tumors is not rare, occurring in up to 50% of breast cancers;however, clinical research and practice underestimate this issue. Many studies have reported the loss of HER... Loss of HER2 in previously HER2-positive breast tumors is not rare, occurring in up to 50% of breast cancers;however, clinical research and practice underestimate this issue. Many studies have reported the loss of HER2 afterneoadjuvant therapy and at metastatic relapse and identified clinicopathological variables more frequentlyassociated with this event. Nevertheless, the biological mechanisms underlying HER2 loss are still poorlyunderstood. HER2 downregulation, intratumoral heterogeneity, clonal selection, and true subtype switch have beensuggested as potential causes of HER2 loss, but translational studies specifically investigating the biology behindHER2 loss are virtually absent. On the other side, technical pitfalls may justify HER2 loss in some of these samples.The best treatment strategy for patients with HER2 loss is currently unknown. Considering the prevalence of thisphenomenon and its apparent correlation with worse outcomes, we believe that correlative studies specificallyaddressing HER2 loss are warranted. 展开更多
关键词 HER2 loss breast cancer subtype switch tumor heterogeneity clonal selection HER2 downregulation technical pitfalls
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早卵泡期长方案降调节时间对IVF-ET助孕结局的影响 被引量:2
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作者 吴润香 李玲 岳林林 《当代医学》 2021年第34期57-59,共3页
目的探究早卵泡期长方案降调节时间对体外受精胚胎移植(IVF-ET)助孕结局的影响。方法回顾性分析2018年1月至2019年9月本院收治的202例IVF-ET患者的临床资料,依据注射促性腺激素释放激素激动剂(GnRH-a)至启动外源性促性腺激素(Gn)时间不... 目的探究早卵泡期长方案降调节时间对体外受精胚胎移植(IVF-ET)助孕结局的影响。方法回顾性分析2018年1月至2019年9月本院收治的202例IVF-ET患者的临床资料,依据注射促性腺激素释放激素激动剂(GnRH-a)至启动外源性促性腺激素(Gn)时间不同分为A组(≤30 d,n=80)、B组(31-35 d,n=70)与C组(≥36 d,n=52)。比较3组Gn启动时卵泡大小、Gn应用时间、Gn用量及临床结局。结果3组Gn启动时卵泡大小比较差异无统计学意义;B组Gn应用时间短于A组、C组,Gn用量少于A组、C组,差异均有统计学意义(P<0.05)。B组获卵数均多于A组、C组,差异有统计学意义(P<0.05);3组可利用胚胎率、移植胚胎数、早期流产率、早发LH峰率比较差异无统计学意义;B组2PN率、临床妊娠率、着床率均高于A组、C组,差异有统计学意义(P<0.05)。结论在早卵泡期长方案中,适当延长垂体降调节时间,能增加IVF-ET的2PN率、临床妊娠率与着床率,减少Gn时间和用量,但垂体降调节时间较长,可能降低获卵数、2PN率、临床妊娠率与着床率。 展开更多
关键词 体外受精-胚胎移植 降调节 促性腺激素释放激素激动剂 外源性促性腺激素
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Notch3表达下调在诱导心肌成纤维细胞向肌成纤维细胞转化中的作用 被引量:2
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作者 邹倩 张东伟 +4 位作者 杜朝升 何薇 李聪叶 范延红 王海昌 《心脏杂志》 CAS 2014年第4期384-387,402,共5页
目的:探讨Notch3在心肌成纤维细胞(CFs)向肌成纤维细胞(MFs)转化中的作用。方法:用胶原酶消化法分离培养SD仔鼠的CFs,将其于不同浓度的转化生长因子-β1(TGF-β1)孵育24 h。用Western blot检测CFs中平滑肌肌动蛋白α(α-SMA)及Notch3的... 目的:探讨Notch3在心肌成纤维细胞(CFs)向肌成纤维细胞(MFs)转化中的作用。方法:用胶原酶消化法分离培养SD仔鼠的CFs,将其于不同浓度的转化生长因子-β1(TGF-β1)孵育24 h。用Western blot检测CFs中平滑肌肌动蛋白α(α-SMA)及Notch3的表达量,用ELISA法检测细胞上清羟脯氨酸含量,用Real-Time PCR检测Notch3 mRNA表达量;利用RNAi法干扰CFs中Notch3的表达,用实时PCR及Western blot检测干扰效果;Western blot检测α-SMA蛋白表达量,ELISA检测各组细胞上清羟脯氨酸含量。结果:TGF-β1可浓度依赖性地诱导CFs细胞上清羟脯氨酸含量增加和α-SMA表达增加,同时使Notch3表达下降,其中2 ng/ml,5 ng/ml,10 ng/ml 3个浓度组与对照组相比有统计学差异(P<0.05)。RNAi法干扰Notch3后,干扰组与对照组相比,Notch3 mRNA及蛋白表达均下降(P<0.05),同时,干扰组细胞上清羟脯氨酸含量及α-SMA表达均增加(P<0.05)。结论:Notch3表达下调能诱导CFs向MFs转化。 展开更多
关键词 NOTCH3 心肌成纤维细胞 肌成细胞 转化
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