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991.
Lung cancer is one of the deadliest cancers, in which non-small cell lung cancer (NSCLC) accounting for 85% and has a low survival rate of 5 years. Dysregulation of microRNAs (miRNAs) can participate in tumor regulation and many major diseases. In this study, we found that miR-199a-3p/5p were down-expressed in NSCLC tissue samples, cell lines, and the patient sample database. MiR-199a-3p/5p overexpression could significantly suppress cell proliferation, migration ability and promote apoptosis. Through software prediction, ras homolog enriched in brain (Rheb) was identified as a common target of miR-199a-3p and miR-199a-5p, which participated in regulating mTOR signaling pathway. The same effect of inhibiting NSCLC appeared after down-regulating the expression of Rheb. Furthermore, our findings revealed that miR-199a can significantly inhibit tumor growth and metastasis in vivo, which fully demonstrates that miR-199a plays a tumor suppressive role in NSCLC. In addition, miR-199a-3p/5p has been shown to enhance the sensitivity of gefitinib to EGFR-T790M in NSCLC. Collectively, these results prove that miR-199a-3p/5p can act as cancer suppressor genes to inhibit the mTOR signaling pathway by targeting Rheb, which in turn inhibits the regulatory process of NSCLC. Thus, to investigate the anti-cancer effect of pre-miR-199a/Rheb/mTOR axis in NSCLC, miR-199a-3p and miR-199a-5p have the potential to become an early diagnostic marker or therapeutic target for NSCLC.  相似文献   
992.
亚热带森林植物群落沿海拔梯度的分类与系统发育研究 生物多样性沿海拔梯度的分布格局已受到广泛关注。然而,生物多样性格局沿海拔梯度的变异及其潜在机制尚不清楚。整合生物多样性的多维度信息为理解群落构建机制提供了新思路。本研究在我国东部亚热带森林沿海拔270–1470 m的梯度上设置了17个木本植物固定样地,分析了沿海拔梯度植物群落 构建的生态和进化驱动力。基于样地内物种出现(0–1数据)和多度信息,计算群落内被子植物的物种和系统发育alpha和beta多样性、系统发育结构等,并量化多样性指标与微气候和地形之间的关系。研究发现,不论多度加权与否,物种alpha多样性均沿海拔升高而增加,物种和系统发育的相似性随海拔距离的增加而呈衰减趋势。然而,多度加权与否会形成不同的系统发育alpha多样性格局。对于系统发育结构而言,沿海拔增加并无明显趋势。地形和微气候是多样性格局和系统发育结构的主要驱动力。与未考虑物种多度的多样性指标相比,多度加权的指标与坡度和胸高断面积相关性更高。这些结果表明,由局域物种多度介导的确定性过程对沿海拔梯度的植物群落构建具有一定影响。  相似文献   
993.

Objective

To explore the feasibility of offering HIV counseling and testing in community health centers (CHCs) and to provide evidence for the HIV/AIDS response in China.

Methods

Forty-two CHCs were selected from the eight cities that participated in the study. Rapid testing was mainly provided to: clients seeking HIV testing and counseling (HTC); outpatients with high-risk behavior of contracting HIV; inpatients and outpatients of key departments. Aggregate administrative data were collected in CHCs and general hospitals and differences between the two categories were compared.

Results

There were 23,609 patients who underwent HIV testing, accounting for 0.37% of all estimated clinic visits at the 42 sites (0.03%–4.35% by site). Overall, positive screening prevalence was 0.41% (95% confidence interval [CI] 0.33%–0.49%, range 0.00%–0.98%), which is higher than in general hospitals (0.17%). The identification efficiency was 0.22% (95% CI: 0.16%–0.27%) in pilot CHCs, 3.5 times higher than in general hospitals (0.06%) (Chi square test = 95.196, p<0.001). The percentage of those receiving confirmatory tests among those who screened positive was slightly lower in CHCs (73.7%) than in general hospitals (80.1%) (Chi-square test = 17.472, p<0.001). Composition of clients mobilized for testing was consistent with the usage of basic public health and medical services in CHCs. The rate of patients testing HIV positive was higher among patients from key CHC departments (0.68%) than among high-risk Voluntary Counseling and Testing (VCT) clients (0.56%), those participating in outreach activities (0.41%), pregnant women (0.05%), and surgical patients (0.00%).

Conclusion

This project demonstrates that providing HIV testing services for patients who exhibit high risk behavior has a high HIV case detection rate and that CHCs have the capacity to integrate HTC into routine work. It provides concrete evidence supporting the involvement of CHCs in the expansion of HIV/AIDS testing and case finding.  相似文献   
994.

Objective

Triple-negative breast cancer (TNBC) patients with truly chemosensitive disease still represent a minority among all TNBC patients. The aim of the present study is to identify microRNAs (miRNAs) that correlate with TNBC chemoresistance.

Methods

In this study, we conducted miRNAs profile comparison between triple-negative breast cancer (TNBCs) and normal breast tissues by microRNA array. Quantitative real-time PCR (qRT-PCR) was utilized to confirm the specific deregulated miRNAs change trend. We used starBase 2.1 and GOrilla to predict the potential targets of the specific miRNAs. Cells viability and apoptosis assays were employed to determine the effect of alteration of the specific miRNAs in TNBC cells on the chemosensitivity.

Results

We identified 11 specific deregulated miRNAs, including 5 up-regulated miRNAs (miR-155-5p, miR-21-3p, miR-181a-5p, miR-181b-5p, and miR-183-5p) and 6 down-regulated miRNAs (miR-10b-5p, miR-451a, miR-125b-5p, miR-31-5p, miR-195-5p and miR-130a-3p). Thereafter, this result was confirmed by qRT-PCR. We predicted the potential targets of the candidate miRNAs and found that they are involved in cancer-associated pathways. For the first time, we found that miR-130a-3p and miR-451a were down-regulated in TNBC. 9 of the 11 specific deregulated miRNAs were found to be associated with chemoresistance. In vitro assays, we found that up-regulation of either miR-130a-3p or miR-451a in MDA-MB-231 cells significantly changed the cells sensitivity to doxorubicin. The results suggest that TNBC chemotherapy might be affected by a cluster of miRNAs.

Conclusion

The abnormal expression miRNAs in TNBC are mainly chemoresistance related. This might be part of reason that TNBC likely to evade from chemotherapy resulting in early relapse and high risk of death. To alter their expression status might be a potential therapeutic strategy to improve the outcome of chemotherapy for TNBC patients.  相似文献   
995.
【目的】本试验测定了两个奶牛场健康乳汁和乳房炎乳汁中微生物菌群的变化,以揭示不同奶牛场之乳汁菌群的异同,评估其对乳汁代谢的影响是否相同。【方法】采用16S rRNA高通量测序技术,分别测定两个奶牛场6头健康奶牛和6头乳房炎奶牛乳汁中微生物16S rRNA V4区序列,并对菌群群落结构和多样性进行比较,分析场内及场间的乳汁菌群差异。【结果】四组乳汁样本共获得4013234条原始序列,经过滤后获得2887024条优化序列。Alpha多样性Chao指数、Ace指数、Shannon指数、Simpson指数差异均不显著(P0.05);Beta多样性四组样本均分别聚类;在场1和场2中,引起奶牛乳房炎的优势菌属分别是克雷伯氏菌属和埃希氏菌属;在2个奶牛场的健康乳汁中,场2的埃希氏菌属、葡萄球菌属的丰度显著高于场1;在2个奶牛场的乳房炎乳汁中,场2的埃希氏菌属、乳球菌属的丰度显著高于场1;2个奶牛场健康乳汁中的嗜冷菌总丰度分别为31.87%和38.72%;关联分析及功能预测分析表明,2个奶牛场健康乳汁与乳房炎乳汁优势物种之间的关系差异较大;场1无论是Level 1还是Level 2水平,均发现显著性差异的代谢通路,而场2均未发现显著性差异的代谢通路。【结论】本试验研究了两个奶牛场健康乳汁和乳房炎乳汁微生物菌群之间的异同,为两个奶牛场在乳房炎的预防工作以及原料奶在冷链运输过程中质量控制提供理论依据。  相似文献   
996.
弓形虫和人乳头瘤病毒 (HPV) 具有共同的免疫保护人群,选择HPV16型晚期结构蛋白1 (HPV16L1) 为载体,携带弓形虫多表位 (RSepitope) 以期提高表位免疫原性同时可实现共免疫效应。文中分别以构建的融合体RSepitope-HPV16L1 (RSepitope融合于HPV16L1“N”端)以及HPV16L1-RSepitope (RSepitope融合于HPV16L1“C”端),脂质体转染COS-7细胞后,RSepitope-HPV16L1融合体形式可以在转染细胞中得到有效转录和翻译,分别可检测到相应的RSepitope和HPV16L1的mRNA和蛋白,但HPV16L1-RSepitope融合体形式在转染细胞中检测不到目标抗原的mRNA和蛋白。融合体采用“DNA初免-蛋白质加强免疫”的方案免疫BALB/c小鼠,酶联免疫吸附试验 (ELISA) 和酶联免疫斑点试验 (ELISPOT) 分别检测到RSepitope-HPV16L1免疫鼠血清中显著升高的体液和细胞免疫反应 (即最高水平的RSepitope特异性抗体IgG和IFN-γ),且比较单独RSepitope免疫组 (不与HPV16L1融合),产生的是显著升高的Th1和Th2免疫反应类型,提示HPV16L1作为表位载体的优势效应。而HPV16L1-RSepitope融合体形式体内也未能诱导有效的免疫反应。以上研究提示,HPV16L1“N”端可能是较为合适的表位融合位置,融合体表位特异性免疫学效应显著提高,研究结果为提高表位疫苗的免疫原性提供了一个合理的载体融合策略。  相似文献   
997.
Duck viral enteritis (DVE) is an acute, contagious herpesvirus infection of ducks, geese, and swans of all ages and species. This disease has been responsible for significant economic losses in domestic and wild waterfowl as a result of mortality, and decreased egg production. Resveratrol is a naturally occurring phytoalexin in specific plants and exhibits inhibitory activity against many kinds of virus. In this paper, resveratrol was found to inhibit duck enteritis virus (DEV) replication in a dose-dependent manner, with a 50% inhibition concentration of 3.85 μg/mL. The inhibition in virus multiplication in the presence of resveratrol was not attributed to direct inactivation or inhibition of virus attachment to the host cells, but to the inhibition of viral multiplication in host cells. The assay of the time of addition limited the drug effect during the first 8 h of infection. This conclusion was supported by the ultrastructure images of the early stage of DEV infection, which showed that the replication of virus nucleic acid and the formation of the capsid in the cell nucleus were suppressed. In the indirect immunofluorescence assay, proteins expression in DEV infected duck embryo fibroblasts (DEFs) within 24 h post-infection (p.i.) was also effectively suppressed by resveratrol. In summary, the resveratrol has a good activity against DEV infection in vitro, which could be attributed to that fact that several essential immediate early viral proteins for virus replication were impacted by resveratrol.  相似文献   
998.
Due to the lack of known therapeutic targets for triple-negative breast cancer (TNBC), chemotherapy is the only available pharmacological treatment. Pirarubicin (tetrahydropyranyl Adriamycin, THP) is the most commonly used anthracycline chemotherapy agent. However, TNBC has a high recurrence rate after chemotherapy, and the mechanisms of chemoresistance and recurrence are not entirely understood. To study the chemoresistance mechanisms, we first screened compounds on a pirarubicin-resistant cell line (MDA-MB-231R) derived from MDA-MB-231. The drug resistance index of MDA-MB-231R cells was approximately five times higher than that of MDA-MB-231 cells. MDA-MB-231R cells have higher GRP78 and lower miR-495-3p expression levels than MDA-MB-231 cells. Transfecting MDA-MB-231R cells with a siGRP78 plasmid reduced GRP78 expression, which restored pirarubicin sensitivity. Besides, transfecting MDA-MB-231R cells with miR-495-3p mimics increased miR-495-3p expression, which also reversed pirarubicin chemoresistance. Cell counting kit-8 (CCK-8), EdU, wound healing, and Transwell assays showed that the miR-495-3p mimics also inhibited cell proliferation and migration. Based on our results, miR-495-3p mimics could down-regulate GRP78 expression via the p-AKT/mTOR signaling pathway in TNBC cells. Remarkably, chemo-resistant and chemo-sensitive TNBC tissues had opposite trends in GRP78 and miR-495-3p expressions. The lower the GRP78 and the higher the miR-495-3p expression, the better prognosis in TNBC patients. Therefore, the mechanism of pirarubicin resistance might involve the miR-495-3p/GRP78/Akt axis, which would provide a possible strategy for treating TNBC.  相似文献   
999.

Background  

Xylose mother liquor has high concentrations of xylose (35%-40%) as well as other sugars such as L-arabinose (10%-15%), galactose (8%-10%), glucose (8%-10%), and other minor sugars. Due to the complexity of this mother liquor, further isolation of xylose by simple method is not possible. In China, more than 50,000 metric tons of xylose mother liquor was produced in 2009, and the management of sugars like xylose that present in the low-cost liquor is a problem.  相似文献   
1000.
The role of long noncoding RNA maternally expressed gene 3 (MEG3) in lung adenocarcinoma has not been explored entirely. In this study, it was demonstrated that the expression of MEG3 was enhanced in lung adenocarcinoma tissues from TCGA database and some specific cell lines, while the survival analysis showed that patients with higher MEG3 levels had lower survival probabilities, which suggested that MEG3 might serve as a lung adenocarcinoma promoter. In addition, the results suggested that the overexpression of MEG3 could promote the proliferation and invasion of lung adenocarcinoma cells. Furthermore, increased MEG3 expression could result in a notable increase in angiogenesis-related factors as well as in the capillary tube formation of endothelial cells, which indicates that the overexpression of MEG3 could promote the angiogenesis of lung adenocarcinoma. From a mechanistic perspective, the results obtained revealed that the upregulation of MEG3 could stimulate the AKT signaling pathway and consequently lead to the biological behaviors mentioned above. In summary, all the results obtained from this study indicated that MEG3 plays a promoting role in the tumorigenesis and angiogenesis of lung adenocarcinoma, which deserves special attention when considered as a potential therapeutic target for lung adenocarcinoma.  相似文献   
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