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241.
目的探索MDCK细胞在微载体上的培养条件,并研究H1N1型流感病毒在MDCK细胞上的增殖条件。方法在微载体上培养好MDCK细胞上用H1N1型流感病毒在不同的病毒感染复数(MOI)、胰酶浓度两个关键的病毒增殖条件进行流感病毒在细胞上的增殖研究。结果微载体质量浓度为6 g/L时,MDCK细胞培养密度可以达到4.5×106cells/mL。在MOI为0.05接种流感病毒,胰酶质量浓度4μg/mL,流感病毒在MDCK细胞上可获得较高的滴度。结论 MDCK细胞用微载体培养可以达到较高的细胞密度,可以作为规模化生产新型流感病毒疫苗的主要细胞基质进行进一步的研究。 相似文献
242.
目的研究肺癌干细胞中piR-932的表达,以期为肺癌的治疗提供参考。方法应用piRNA芯片检测肺癌于细胞中piRNAs的表达,应用基因芯片检测肺癌干细胞中基因表达的差异,并检测表达下调的基因之一——Latexin的甲基化程度。结果经诱导至EMT的肺癌干细胞中,piR-932的表达明显增高,而Latexin的表达显著下降,并且Latexin启动子区域CpG岛发生了明显的甲基化。结论piR-932可能通过促进Latexin的甲基化而正渊节肺癌干细胞的EMT过程,它可作为肺癌治疗的一个潜在靶点。 相似文献
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245.
DUAN AiPing NING LiMin LI Chao HOU YaFei YANG NaNa SUN LiZhou LI GenXi 《中国科学:生命科学英文版》2013,56(4):293-297
Hepatitis C virus (HCV), a positive single-stranded RNA virus, is a major cause of liver disease in humans. Herein we report a novel strategy to inhibit the reproduction and translation of HCV using a short RNA, named an Additional RNA, to activate the endonuclease activity of Argonaute 2 (Ago2). In the presence of the Additional RNA, the HCV genome RNA has the requisite 12 nucleotides of base-pairing with microRNA-122. This activates the endonuclease activity of Ago2, resulting in cleavage and release of the HCV genome RNA from Ago2 and microRNA-122. The free HCV genome RNA would be susceptible to intracellular degradation, effectively inhibiting its reproduction and translation. This study presents a new method to inhibit HCV that may hold great potential for HCV treatment in the future. 相似文献
246.
Huanan Wen Jiaxin Zhong Bei Shen Tao Gan Chao Fu Zhihong Zhu Rui Li Xu Yang 《生物学前沿》2013,8(4):444-450
To compare the cytotoxicity on HeLa cells induced by nanosized and microsized tellurium powders, HeLa cells were exposed to different concentrations of tellurium powders (0, 50, 100, 150 and 200 μg/mL) for 12 h. In this study, detection of a series of biomarkers, including reactive oxygen species (ROS), glutathione (GSH), 8-hydroxy-2′-deoxyguanosine (8-OHdG), in addition to DNA and protein crosslink (DPC) and MTTassay, were conducted to evaluate the cytotoxicity. It is indicated that compared with the control group, there was no significant difference in the induced cytotoxicity at concentrations lower than 50 μg/mL for both nanosized and microsized tellurium powders. While there appears a significant difference in the induced cytotoxicity for nanosized tellurium powders when the concentration is higher than 100 μg/mL as well as for microsized tellurium powders when the concentration is higher than 200 μg/mL. Moreover, it is found that the cytotoxicity induced on HeLa cells exhibits a certain dose-effect relationship with the concentration of tellurium powders. A conclusion has been reached that the toxicity on HeLa cells can be induced by both nanosized and microsized tellurium powders, and the toxicity of the nanosized tellurium powders is significantly greater than the microsized one. 相似文献
247.
Xiaozhou He Yilin Yang Feng Zhi Meredith L. Moore Xuezhi Kang Dongman Chao Rong Wang Gianfranco Balboni Severo Salvadori Dong H. Kim Ying Xia 《PloS one》2013,8(4)
Hypoxic/ischemic injury to kidney is a frequently encountered clinical problem with limited therapeutic options. Since microRNAs are differentially involved in hypoxic/ischemic events and δ-opioid receptor (DOR) activation is known to protect against hypoxic/ischemic injury, we speculated on the involvement of DOR activation in altering the microRNA (miRNA) expression in kidney under hypoxic condition. We selected 31 miRNAs based on microarray data for quantitative PCR analysis. Among them, 14 miRNAs were significantly altered after prolonged hypoxia, DOR activation or a combination of both. We found that 1) DOR activation alters miRNA expression profiles in normoxic conditions; 2) hypoxia differentially alters miRNA expression depending on the duration of hypoxia; and 3) DOR activation can modify hypoxia-induced changes in miRNA expression. For example, 10-day hypoxia reduced the level of miR-212 by over 70%, while DOR activation could mimic such reduction even in normoxic kidney. In contrast, the same stress increased miR-29a by >100%, which was reversed following DOR activation. These first data suggest that hypoxia comprehensively modifies the miRNA profile within the kidney, which can be mimicked or modified by DOR activation. Ascertaining the targeted pathways that regulate the diverse cellular and molecular functions of miRNA may provide new insights into potential therapies for hypoxic/ischemic injury of the kidney. 相似文献
248.
Rationale and Objective
Sirtuin 1 (SIRT1) plays an important role in tumorigenesis and is increased in many human tumors. DBC1 is a negative regulator of SIRT1 via promotion of p53-mediated apoptosis. It is necessary to investigate the expression of SIRT1 and DBC1 in laryngeal and hypopharyngeal squamous cell carcinomas (LSCC and HSCC) and its correlation with available clinical parameters.Methods
The mRNA levels of SIRT1 and DBC1 were measured in 54 paired LSCC or HSCC tumors and corresponding adjacent noncancerous mucosae using quantitative RT-PCR (qRT-PCR). The protein levels of SIRT1 and DBC1 were also evaluated in 120 cases of patients with LSCC or HSCC using immunohistochemical staining. The correlation between SIRT1 and DBC1 expression and clinical parameters was analyzed with Pearson chi-square test.Results
qRT-PCR assay showed that, compared with the paired adjacent noncancerous mucosae, SIRT1 mRNA was significantly decreased in tumors. The immunohistochemical results indicated that the SIRT1 protein was also downregulated in tumors compared with noncancerous mucosae. Moreover, decreased SIRT1 was significantly correlated with the tumor clinical stage and lymph node metastasis. Additionally, DBC1 mRNA was significantly increased in tumors compared with noncancerous mucosae. The immunohistochemical results indicated that the DBC1 protein was downregulated in tumors, which is inconsistent with the results obtained by qRT-PCR. Finally, decreased DBC1 protein was significantly correlated with tumor differentiation, lymph node metastasis, and p53 expression.Conclusions
SIRT1 and DBC1 might be involved in the pathophysiology of laryngeal and hypopharyngeal squamous cell carcinomas and are associated with lymph node metastasis and p53 positive staining in LSCCs and HSCCs. 相似文献249.
Lianzheng Yu Chao Jiang Jun Na Ning Li Wenli Diao Yuan Gu Li Zhao Yan Zou Ying Chen Li Liu Huijuan Mu Yunyong Liu Liya Yu Xiaoli Yang Guowei Pan 《PloS one》2013,8(4)
Background
This study aimed to assess whether Chinese men who have sex with men (MSM) had a significantly elevated prevalence of psychiatric disorders compared to urban males in China.Methods
807 MSM were recruited using a respondent-driven sampling (RDS) method in urban area of northeast China. Psychiatric disorders were assessed employing the Composite International Diagnostic Interview (CIDI. Version 1.0) according to the criteria of the DSM-III-R.Results
Chinese MSM had a significantly elevated standardized prevalence ratios (SPR) for lifetime prevalence of any disorder (SPR = 2.8; 95%CI: 2.5–3.2), mood disorder (SPR = 3.0; 95%CI: 2.3–3.7), anxiety disorder (SPR = 5.5; 95% CI: 4.6–6.5), alcohol use disorder (SPR = 2.4, 95%CI: 2.0–2.8), and combination of disorders (SPR = 4.2; 95%CI: 3.4–5.1).Conclusions
Chinese MSM had significantly elevated prevalence and comorbidity of psychiatric disorders. RDS is a suitable sampling method for psychiatric epidemiological survey in MSM population. 相似文献250.
Chunmei Zhang Chao Yang Ruifei Wang Yang Jiao Khamal Kwesi Ampah Xiaoguang Wang Xianlu Zeng 《PloS one》2013,8(6)
Integrins are heterodimeric transmembrane receptors that physically link the extracellular matrix (ECM) to the intracellular actin cytoskeleton, and are also signaling molecules that transduce signals bi-directionally across the plasma membrane. Integrin regulation is essential for tumor cell migration in response to growth factors. c-Abl kinase is a nonreceptor tyrosine kinase and is critical for signaling transduction from various receptors. Here we show that c-Abl kinase is involved in A375 cell migration mediated by αvβ3 integrin in response to PDGF stimulation. c-Abl kinase colocalizes with αvβ3 integrin dynamically and affects αvβ3 integrin affinity by regulating its cluster. The interaction between c-Abl kinase and αvβ3 integrin was dependent on the activity of c-Abl kinase induced by PDGF stimulation, but was not dependent on the binding of αvβ3 integrin with its ligands, suggesting that c-Abl kinase is not involved in the outside-in signaling of αvβ3 integrin. Talin head domain was required for the interaction between c-Abl kinase and αvβ3 integrin, and the SH3 domain of c-Abl kinase was involved in its interaction with talin and αvβ3 integrin. Taken together, we have uncovered a novel and critical role of c-Abl kinase in αvβ3 integrin mediated melanoma cell migration. 相似文献