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51.

Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
52.
BackgroundAccurate diagnosis of the disease extension of cholangiocarcinoma (CCA) is often difficult in clinical practice. The diagnostic yield of conventional pre-operative imaging or endoscopic procedures is sometimes insufficient for the evaluation of longitudinal spreading of CCA. Here we investigated the usefulness of 5-aminolevulinic acid (5-ALA) for the pre- or intra-operative diagnosis of CCA, using patient-derived organoids.MethodsFour CCA- and two adjacent tissue-derived organoids were established. After 5-ALA treatment, we assessed their photodynamic activity using fluorescence microscopy.ResultsCCA organoids established from different patients showed diverse morphology in contrast to monolayer structures of non-tumor organoids, and had the ability to form subcutaneous tumors in immunodeficient mice. CCA organoids demonstrated remarkably high photodynamic activity based on higher accumulation of protoporphyrin IX as a metabolite of 5-ALA compared to non-tumor organoids (40–71% vs. < 4%, respectively). Importantly, cancer cell-specific high photodynamic activity distinguished the organoids originated from biliary stenotic lesions from those of non-stenotic lesions in a CCA patient. The high photodynamic activity did not depend on the expression profile of heme biosynthesis genes.ConclusionsDistinct 5-ALA-based photodynamic activity could have diagnostic potential for the discrimination of CCA from non-tumor tissues.  相似文献   
53.
54.
目的:观察综合疗法治疗慢性肾脏病(CKD)4~5期脾肾亏虚证的效果。方法:将CKD4~5期脾肾亏虚证患者62例随机分为2组,其中治疗组31例,对照组30例(剔除1例)。对照组予基础治疗合中药、骨化三醇及碳酸钙D3片治疗,治疗组予基础治疗合中药、骨化三醇及益肾泄浊汤保留灌肠治疗,观察时间为4周。比较2组血肌酐(Scr)、肾小球滤过率(e GFR)、尿素氮(BUN)、血钙、血磷、碱性磷酸酶(ALP)、甲状旁腺激素(i PTH)及中医证候疗效。结果:中医证候总有效率治疗组为83.87%(26/31),对照组为73.33%(22/30),组间比较,差异有统计学意义(P<0.05);2组Scr、e GFR、BUN、血磷治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.01或P<0.05);2组血钙、i PTH、ALP治疗前后组内比较,差异均有统计学意义(P<0.01),但治疗后组间比较,差异无统计学意义(P>0.05)。结论:综合疗法治疗慢性肾脏病4~5期脾肾亏虚证效果确切,安全可靠。  相似文献   
55.
背景与目的:结肠癌是临床常见恶性肿瘤,探讨抑癌蛋白T-cadherin在结肠癌中的表达情况及其与患者临床病理学特征的关系,并分析5-Aza-CdR对T-cadherin表达和结肠癌细胞增殖、侵袭及凋亡的影响。方法:收集福建医科大学附属第二医院2015—2016年40例手术切除的结肠癌组织及癌旁组织新鲜样本,并经过病理学检查验证,分别提取总RNA和总蛋白质。采用实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)分析T-cadherin mRNA的表达,采用蛋白质印迹法(Western blot)分析T-cadherin蛋白水平,并分析T-cadherin的mRNA表达变化与患者临床病理学特征的关系。进一步以人结肠癌细胞系HT-29为研究对象,采用甲基化抑制剂5-Aza-CdR处理HT-29细胞,分别采用RTFQ-PCR和Western blot分析T-cadherin表达变化,采用细胞计数试剂盒(cell counting kit-8,CCK-8)分析细胞增殖,采用Transwell实验验证细胞侵袭能力,采用流式细胞术分析细胞凋亡。结果:T-cadherin在结肠癌组织的蛋白水平和mRNA表达均明显低于癌旁组织,其mRNA表达与淋巴结转移(F=5.316,P=0.009 3)和分化程度(F=5.807,P=0.006 4)明显相关,而与其他病理变量(包括性别、年龄、肿瘤大小和肿瘤浸润深度)无明显相关。药物5-Aza-CdR可以显著上调HT-29细胞中T-cadherin的表达水平,抑制HT-29细胞增殖、侵袭并促进细胞凋亡。结论:T-cadherin表达可能与结肠癌恶性程度密切相关,药物5-Aza-CdR处理可上调结肠癌细胞T-cadherin的表达,并抑制结肠癌细胞的增殖、迁移,促进结肠癌细胞凋亡,提示T-cadherin可能是结肠癌患者使用甲基化抑制剂5-Aza-CdR治疗的靶点。  相似文献   
56.
Objective: To determine serotonin system abnormalities related to major depression or previous suicidal behavior.

Methods: [11C]WAY100635, [18F]altanserin and positron emission tomography were used to compare 5-HT1A and 5-HT2A binding in MDD patients divided into eight past suicide attempters (>4yrs prior to scanning) and eight lifetime non-attempters, and both groups were compared to eight healthy volunteers.

Results: The two receptor types differed in binding pattern across brain regions from each other, but there were no differences in binding between healthy volunteers and the two depressed groups or between depressed suicide attempters and non-attempters. No effects of depression severity or lifetime aggression were observed for either receptor.

Conclusion: Limitations of this study include small sample size and absence of high lethality suicide attempts in the depressed attempter group. No trait-like binding correlations with past suicide attempt or current depression were observed. Given the heterogeneity of nonfatal suicidal behavior, a larger sample study emphasizing higher lethality suicide attempts may find the serotonin biological phenotype seen in suicide decedents.  相似文献   

57.
以培养创新型人才为目标,大连医科大学制定实施了“5+3”创新人才培养改革方案,以导师制培养为载体,在医学本科教育全过程中,制定分阶段创新能力培养体系,涵盖课程、讲座、实验设计、论文等基本科研能力训练,强化本科生科研能力培养。通过对首届“5+3”学生阶段性培养成果的统计学分析发现,“5+3”学生发表中文期刊、SCI,主持国家级创新项目、省级创新项目的比例均显著高于普通5年制学生,差异具有统计学意义(P<0.05)。虽然实施过程中存在一些问题和不足,但以导师制为核心的科研基础训练对提高学生科研思维和创新能力效果显著,对培养医学创新型人才具有可实施性。  相似文献   
58.
The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development. Direct acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens.  相似文献   
59.
Chondrosarcoma is the second most common form of bone cancer and is characterized by its ability to produce an extracellular matrix of the cartilage. High-grade chondrosarcoma is highly aggressive and can metastasize to other parts of the body. Chondrosarcoma is resistant to both conventional chemotherapy and radiotherapy; hence, the current main treatment is still surgical resection. Doxorubicin (Dox) has been shown to significantly improve patient survival compared with untreated chondrosarcoma. However, for patients with metastasis, surgical resection alone can hardly treat them. In addition, drug resistance is one of the leading causes of death in patients with chondrosarcoma. Secreted proteins can mediate cell-cell interactions in the cancer microenvironment, which may be associated with the development of drug resistance. In the present study, chondrosarcoma cells were treated with Dox, the conditioned medium was then collected and changes in secreted proteins were analyzed using the antibody array. Results showed that the Dox-treated group had the highest secretion of basic fibroblast growth factor (bFGF), indicating the effect of bFGF on Dox sensitivity in chondrosarcoma. Furthermore, lentiviral-mediated knockdown and treatment of exogenous recombinant protein were employed to further investigate the effect of bFGF on Dox resistance. Results demonstrated that bFGF can promote the expression of X-ray repair cross-complementing protein 5 (XRCC5), leading to Dox resistance. Secreted bFGF is likely to be detected in serum, in addition to being a biomarker for predicting Dox resistance, the combination of Dox and bFGF/XRCC5 blockers may be a new therapeutic strategy to improve the efficacy of Dox in future.  相似文献   
60.
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