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61.
62.

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   
63.
Cancer immunotherapy has achieved unprecedented success in the treatment of cancer. However, different patients have different responses to immunotherapy. More and more studies have shown that tumor immune heterogeneity has an important influence on the prognosis of cancer. Therefore, understanding the clinical impact of tumor immune infiltration and the regulatory mechanism of RNA molecules is crucial for exploring the pathogenesis of lung adenocarcinoma (LUAD) and the development of immunotherapy protocols.The endogenous competitive RNA hypothesis provides new ideas for studying immune heterogeneity. Therefore, by using the method of immune genomics, this article explores the relationship between immune infiltration and prognosis of patients with lung adenocarcinoma, and found that B-cell immune infiltration highly affects the survival of patients. Through differential analysis, differential mRNAs, lncRNAs and miRNAs were extracted, and 318 differentially expressed mRNAs related to B cell immunity were screened by correlation analysis, and prognosis of patients with COX risk regression model was predicted and analyzed. Through multiple database searches, an immune-related ceRNA regulatory network was constructed, containing 3 key mRNAs, 4 miRNAs, and 50 lncRNAs. Three mRNAs and most miRNAs, lncRNAs, are significantly associated with LUAD prognosis. Bioinformatics analysis of the network showed that LINC00337 may up-regulate the expression of PBK and KIF23 through competitive binding of has-mir-373 and has-mir-519d. The competitive binding of has-mir-373 and has-mir-372 can up-regulate the expression of SLC7A11. The interaction between these RNAs may have an important regulatory role in the immune infiltration in lung adenocarcinoma, thereby affecting the patient's prognosis and immunotherapy efficacy.  相似文献   
64.
65.
In insects, lipid digestion is controversial because insects have no bile salts to solubilize dietary lipids. One hypothesis is that a secretory type of phospholipase A2 (sPLA2) provides lysophospholipid (LPL) from dietary phospholipids (PLs). We identified a sPLA2, Se‐sPLA2, in beet armyworm, Spodoptera exigua, that hydrolyses PLs at sn‐2. Our goal was to investigate its role in lipid digestion. Se‐sPLA2 was expressed in the entire alimentary canal. Incubating the isolated midgut in a cell culture medium led to secretion of Se‐sPLA2 and other proteins. Ex vivo RNA interference (RNAi) of Se‐sPLA2 expression in isolated midgut culture led to significantly decreased Se‐sPLA2 secretion into the medium. Feeding double‐stranded RNA specific to Se‐sPLA2 to larvae suppressed sPLA2 activity in gut contents. A recombinant Se‐sPLA2 was susceptible to benzylideneacetone (BZA), a specific PLA2 inhibitor. After feeding BZA to larvae, we recorded significant decreases in gut content sPLA2 activity, body growth and total haemolymph lipid contents. RNAi against Se‐sPLA2 resulted in reduced digestibility. Addition of a specific LPL, 1‐palmitoyl‐sn‐glycero‐3‐phosphocholine, to BZA‐treated larvae rescued digestibility and larval growth. These results strongly bolster our hypothesis that Se‐sPLA2 secreted from the midgut acts in lipid digestion by providing necessary LPL to solubilize dietary neutral lipids.  相似文献   
66.
肝癌是临床常见消化道恶性肿瘤,其发生呈现多阶段性:肝炎-肝硬化-肝癌癌前病变-肝癌。其中肝癌癌前病变恶变成为肝癌的机制尚不完全明确,可能受Kupper细胞极化方向的影响。Kupffer细胞是肝脏中特殊的单核巨噬细胞,可在不同的微环境中分化出不同的表型即M1型和M2型,表现出不同的功能,在肝癌中发挥抑癌或促癌的作用。研究发现多种miRNA、LncRNA可通过靶向干预Kupffer极化相关蛋白进而调控其极化方向,从而影响肝癌癌前病变的发生、发展及恶变,降低肝癌的发生率。本文主要阐述上述研究的前沿进展,为肝癌的防治提供参考。  相似文献   
67.
《Clinical breast cancer》2020,20(5):422-430
BackgroundBreast cancer is the most commonly diagnosed cancer and the leading cause of cancer death among females. Circular RNAs (circRNAs) have been implicated in the initiation and development of cancer. Here, we explored the biological role and regulatory mechanism of circCDYL in breast cancer.Materials and MethodsThe expression and correlation of circCDYL/miR-190a-3p/TP53INP1 axis in breast cancer tissues and cells were determined by quantitative polymerase chain reaction and Western blot. Cell-counting Kit-8, colony formation, cell migration, and invasion assays were applied to investigate the biological roles of circCDYL in breast cancer development and progression.ResultsCircCDYL were down-regulated in breast cancer tissues and cells, the expression of which positively correlated with patients’ survival rate. CircCDYL worked as a “sponge,” binding to miR-190a-3p directly, which inhibited the expression of miR-190a-3p and relieved the inhibition of tumor suppressor gene TP53INP1.ConclusionCircCDYL promotes apoptosis and inhibits proliferation of the malignant phenotype of breast cancer through regulating miR-190a-3p/TP53INP1 axis, which suggests that circCDYL is a potential therapeutic target for breast cancer.  相似文献   
68.
目的:探索以系统化、标准化的新型冠状病毒核酸检测为核心和重要组成部分,建立适合于眼科医院新冠疫情精准防控切实可行的防控体系。方法:系列病例研究。自2020年2月24日至3月2日期间,以标准化病毒核酸检测联合血常规、C反应蛋白(CRP)、血清淀粉样蛋白A(SAA)等检测作为所有眼科手术患者术前筛查常规检测项目,同时也为返岗员工提供病毒核酸检测。设计调查问卷了解受检者对鼻咽拭子采样的接受度以及核酸检测结果对其心理状态的影响。结果:99例患者血液学检测结果有一定的异常比例,其中SAA检测结果增高13例,淋巴细胞计数减低12例、增高5例,白细胞计数增高11例、减低1例,CRP增高2例,新型冠状病毒核酸检测均阴性。33例本院职工新型冠状病毒核酸检测均阴性。12%的受访者对鼻咽拭子采样接受度评分较低。受检者在核酸检测前后思想压力评分较高的比例分别为46.7%和6.7%。结论:该项举措一方面为术前新冠病毒肺炎筛查及鉴别诊断提供了客观依据,很大程度上排除了隐性无症状感染者传播的可能,有利于减少二次传播的风险,降低院内交叉感染的概率;另一方面,核酸检测阴性结果有利于调整患者术前的心理状态并缓解医护人员在疫情防控期间的心理压力。  相似文献   
69.
Epigenetics refers broadly to processes that influence medium to long‐term gene expression by changing the readability and accessibility of the genetic code. The Neurobiology Commission of the International League Against Epilepsy (ILAE) recently convened a Task Force to explore and disseminate advances in epigenetics to better understand their role and intersection with genetics and the neurobiology of epilepsies and their co‐morbidities, and to accelerate translation of these findings into the development of better therapies. Here, we provide a topic primer on epigenetics, explaining the key processes and findings to date in experimental and human epilepsy. We review the growing list of genes with epigenetic functions that have been linked with epilepsy in humans. We consider potential practical applications, including using epigenetic signals as biomarkers for tissue‐ and biofluid‐based diagnostics and the prospects for developing epigenetic‐based treatments for epilepsy. We include a glossary of terms, FAQs and other supports to facilitate a broad understanding of the topic for the non‐expert. Last, we review the limitations, research gaps and the next challenges. In summary, epigenetic processes represent important mechanisms controlling the activity of genes, providing opportunities for insight into disease mechanisms, biomarkers and novel therapies for epilepsy.  相似文献   
70.
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