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101.
Ghasem Rahimi Kalateh Shah Mohammad Ehsan Karimi Ehsan Oskoueian Masoud Homayouni-Tabrizi 《Andrologia》2020,52(1):e13450
The unclear bio-safety issue and potential risk of nanoparticles (NPs) on various organelles can be considered as a major challenge. In the present study, we have assessed the green synthesis of ZnO nanoparticles using Hyssop (Hyssopus officinalis) extract and their effects on PC3 cell line and BALB/c mice model. The cytotoxicity of the ZnO-NPs was assessed on PC3 cell line by MTT test after characterisation. Apoptotic effect of ZnO-NPs was determined by in vitro AO/PI staining. The histopathological assessments and determination of LH and FSH levels carried out as in vivo analysis in BALB/c adult male mice. The expression of major genes involved in spermatogenesis and sperm maturation (Adam3, Prm1, Spata19, Tnp2, Gpx5) were also analysed. The obtained result demonstrated that the IC50 for PC3 cell line treated with green-synthesised ZnO-NPs during 24 and 48 hr was reported 8.07 and 5 µg/ml respectively. Meanwhile, the induced apoptosis was recorded 26.6% ± 0.05, 44% ± 0.12 and 80% ± 0.07 of PC3 cells. The results of gene expression analysis revealed that the increase in the concentration of ZnO-NPs significantly (p < .05) down-regulated the Adam3, Prm1, Spata-19, Tnp2 and Gpx5 genes. The overall results of this research elucidated that ZnO-NPs impaired spermatogenesis, sperm maturation process and sperm motility. 相似文献
102.
目的探讨6-磷酸果糖激酶-2/果糖双磷酸酶-2同工酶3(PFKFB3)基因在前列腺癌中的表达及其对前列腺癌细胞糖酵解及生长的影响。
方法收集我院病理科前列腺增生和前列腺癌蜡块组织,应用免疫组化技术检测PFKFB3的表达水平。通过荧光定量PCR和Western blot实验检测正常前列腺上皮细胞(RWPE-1)和四种前列腺癌细胞系(PC3、LNCaP、DU145、C4-2)中PFKFB3的表达。应用RNA干扰技术敲低PFKFB3表达,采用细胞糖酵解试剂盒、CCK-8和克隆形成实验检测PFKFB3对前列腺癌细胞的糖酵解和增殖活性的影响。
结果与前列腺增生组织相比,前列腺癌组织中的PFKFB3表达量明显增高[(59.7±0.25) vs (3.08±0.16),P<0.05],且病理Gleason评分越高,PFKFB3表达量也越高。同样PFKFB3在不同前列腺癌细胞系中均明显高表达。抑制PFKFB3基因表达后,前列腺癌细胞的糖酵解和增殖能力显著降低。
结论PFKFB3基因在前列腺癌恶性进展中表达上调,促进肿瘤细胞的糖酵解和增殖,靶向PFKFB3可能为前列腺癌分子诊断和治疗提供潜在的应用价值。 相似文献
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104.
血管内皮细胞糖萼是位于内皮细胞表面的一层多糖蛋白复合结构,在内皮细胞表面形成选择性通透屏障。在对糖萼进行概述后,主要针对在流动剪切力作用下,糖萼与物质传输,尤其是与大分子物质如低密度脂蛋白(low density lipoprotein,LDL)的关系展开论述。其关系体现为:一方面,糖萼的厚度和完整性影响LDL的浓度极化及跨内膜输运;糖萼中的硫酸肝素蛋白聚糖参与残余脂蛋白代谢的全过程。另一方面,LDL的氧化产物ox-LDL会破坏内皮细胞糖萼层的主要成分硫酸肝素。研究糖萼与脂蛋白的关系,将为阐明动脉粥样硬化的发病机理提供新的线索,并为将糖萼作为新的防治靶点提供更多依据。 相似文献
105.
106.
Study of promoter hypomethylation profiles of RAS oncogenes in hepatocellular carcinoma derived from hepatitis C virus genotype 3a in Pakistani population 下载免费PDF全文
Epigenetic modifications such as DNA methylation contribute to progression of hepatitis C virus (HCV) infection to life‐threatening hepatocellular carcinoma (HCC) by promoting the silencing of tumor suppressor genes through DNA hypermethylation and by causing genomic instability through global hypomethylation. However few studies have addressed the promoter region hypomethylation status of the oncogenes involved in HCV derived HCC. In this study, we analyzed the promoter region methylation pattern of RAS oncogenes (HRAS, KRAS, and NRAS) using methylation‐specific PCR for 50 chronic HCV patients infected with genotype 3a (27 HCC patients and 23 control non‐HCC patients). Methylation‐specific polymerase chain reaction analysis revealed that the NRAS oncogene promoter (P = .0025) was significantly hypomethylated in HCC patients compared to the non‐HCC patients suggesting its contribution to the progression of HCV towards HCC. To identify the agent for alteration in the RAS oncogene expression, 7 HCV genes were expressed in the Huh‐7 cell line followed by measurement of the NRAS expression level in Huh‐7 by a quantitative real‐time polymerase chain reaction. An increase in the messenger RNA level of the NRAS gene was detected when Huh‐7 were transfected with Core, NS5a, and NS2 genes. Our findings suggest the involvement of NRAS oncogene in the pathogenesis of HCV3a derived HCC in Pakistani population and also identifies the HCV genes responsible for its enhanced expression. Our study raises the hypothesis that a single HCV gene may increase the chances of malignancy. Therefore, our study may have identified a useful epigenetic biomarker of HCC progression in HCV patients and may help to develop novel diagnostic tools. 相似文献
107.
Milica Jovanović Krivokuća Ivana Stefanoska Tamara Abu Rabi Milan Marković Srđa Janković Svetlana Vrzić-Petronijević Ljiljana Vićovac 《Immunobiology》2018,223(10):544-548
Women with antiphospholipid syndrome (APS) experience pregnancy complications mostly due to impaired trophoblast cell functions. Antiphospholipid antibodies (aPL) affect extravillous trophoblast in vivo and in culture, but the mechanisms are still poorly understood. Previously, syncytiotrophoblast was shown to bind and internalize aPL, which was not replicated for extravillous cytotrophoblast in short term culture. Here, aPL binding and time dependent internalization was demonstrated with exposure to aPL in the extravillous cell line HTR-8/SVneo and isolated first trimester of pregnancy cytotrophoblast (CT) using immunocytochemistry and flow cytometry. Intracellular aPL were detectable from 2?h of culture, reaching 30.7?±?3.1% (p?<?0.001) positive cells in CT and 24.8?±?7% (p?<?0.01) in HTR-8/SVneo cells at 24?h and 33?±?4.2% (p?<?0.01) at 48?h. The data presented show that extravillous trophoblast cells internalize aPL in a time-dependent manner significantly more than control immunoglobulins after 24?h of exposure. 相似文献
108.
109.
110.
Mustafa Altunsoy Murat Selim Botsali Emre Korkut Ebru Kucukyilmaz Yagmur Sener 《Acta odontologica Scandinavica》2014,72(8):874-879
Objective. The aim of this study was to evaluate the effect of different surface treatments on the microtensile bond strength (μTBS) and shear bond strength (SBS) of resin-modified glass ionomer cement (RMGIC) to dentin. Materials and methods. Fifty-two extracted human molars were flattened to obtain dentin surfaces. For SBS assessment 40 teeth were divided into four groups according to their surface treatments (acid etching, Er:YAG laser QSP mode, Er:YAG laser MSP mode and control-SiC) (n = 10). A plastic cylinder was placed over the differently treated dentin surfaces and RMGIC was placed into the rings and polymerized. Twelve teeth were used for the μTBS test. The treated dentin surfaces described above were restored with 4 mm high RMGIC and light cured; then, the specimens were sectioned into serial sticks (n = 15) and μTBS and SBS were tested for failure in a testing machine with a 1 mm/min crosshead speed. The data were analyzed by one-way ANOVA and Tukey HSD tests (α = 0.05). Results. Acid etching showed significantly higher SBS than the other groups (p < 0.05). Er:YAG QSP and MSP-treated groups showed higher SBS values than the control group, but the difference was not statistically significant (p > 0.05). Er:YAG MSP showed the highest μTBS value followed by acid etching, whereas the control group exhibited the lowest value (p < 0.05) and the differences between the control group and Er:YAG QSP were not significant (p > 0.05). Conclusions. The application of Er:YAG MSP mode and acid etching to dentin can be used for improving the bond strength of RMGIC. 相似文献