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排序方式: 共有199条查询结果,搜索用时 31 毫秒
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Cardiomyopathies (CMPs) are a heterogeneous group of myocardial diseases accountable for the majority of cases of heart failure (HF) and/or sudden cardiac death (SCD) worldwide. With the recent advances in genomics, the original classification of CMPs on the basis of morphological and functional criteria (dilated (DCM), hypertrophic (HCM), restrictive (RCM), and arrhythmogenic ventricular cardiomyopathy (AVC)) was further refined into genetic (inherited or familial) and acquired (non-inherited or secondary) forms. Despite substantial progress in the identification of novel CMP-associated genetic variations, as well as improved clinical recognition diagnoses, the functional consequences of these mutations and the exact details of the signaling pathways leading to hypertrophy, dilation, and/or contractile impairment remain elusive. To date, global research has mainly focused on the genetic factors underlying CMP pathogenesis. However, growing evidence shows that alterations in molecular mediators associated with the diagnosis of CMPs are not always correlated with genetic mutations, suggesting that additional mechanisms, such as epigenetics, may play a role in the onset or progression of CMPs. This review summarizes published findings of inherited CMPs with a specific focus on the potential role of epigenetic mechanisms in regulating these cardiac disorders. 相似文献
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采用在废旧轮胎胶粉(GTR)与高密度聚乙烯(PE-HD)的熔融挤出过程中提高双螺杆挤出机螺杆转速的高剪切应力诱导方法,研究了双螺杆挤出机的螺杆转速、挤出反应温度及脱硫促进剂仲丁醇、烷基酚多硫化物(420或450)和正丁胺对轮胎胶脱硫共混物的凝胶含量、熔体流动速率、溶胶红外吸收光谱及轮胎胶脱硫共混物/三元乙丙橡胶(EPDM)动态交联热塑性弹性体力学性能的影响。结果表明:高转速同向双螺杆挤出机的高剪切作用可诱发废旧轮胎胶共混物中交联网络的断链和解交联反应,引起脱硫共混物凝胶含量的下降、未熔融凝胶颗粒尺寸的减小及熔体流动速率的增加;4种促进剂均具有明显促进脱硫反应的作用,其中450或正丁胺的促进脱硫效果较好,并引起脱硫共混物凝胶含量下降、熔体流动速率上升及动态交联热塑性弹性体力学性能的明显改善;当以正丁胺为脱硫促进剂时,最佳脱硫反应条件(240℃和1000r/min)下,脱硫共混物/EPDM动态交联热塑性弹性体的拉伸强度和断裂伸长率分别达到12.5MPa和440.6%。 相似文献
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Stephanie Simoncini Hanna Coppola Angela Rocca Isaline Bachmann Estelle Guillot Leila Zippo Franoise Dignat-George Florence Sabatier Romain Bedel Anne Wilson Nathalie Rosenblatt-Velin Jean-Baptiste Armengaud Steeve Mentrey Anne-Christine Peyter Umberto Simeoni Catherine Yzydorczyk 《International journal of molecular sciences》2021,22(18)
Infants born after intrauterine growth restriction (IUGR) are at risk of developing arterial hypertension at adulthood. The endothelium plays a major role in the pathogenesis of hypertension. Endothelial colony-forming cells (ECFCs), critical circulating components of the endothelium, are involved in vasculo-and angiogenesis and in endothelium repair. We previously described impaired functionality of ECFCs in cord blood of low-birth-weight newborns. However, whether early ECFC alterations persist thereafter and could be associated with hypertension in individuals born after IUGR remains unknown. A rat model of IUGR was induced by a maternal low-protein diet during gestation versus a control (CTRL) diet. In six-month-old offspring, only IUGR males have increased systolic blood pressure (tail-cuff plethysmography) and microvascular rarefaction (immunofluorescence). ECFCs isolated from bone marrow of IUGR versus CTRL males displayed a decreased proportion of CD31+ versus CD146+ staining on CD45− cells, CD34 expression (flow cytometry, immunofluorescence), reduced proliferation (BrdU incorporation), and an impaired capacity to form capillary-like structures (Matrigel test), associated with an impaired angiogenic profile (immunofluorescence). These dysfunctions were associated with oxidative stress (increased superoxide anion levels (fluorescent dye), decreased superoxide dismutase protein expression, increased DNA damage (immunofluorescence), and stress-induced premature senescence (SIPS; increased beta-galactosidase activity, increased p16INK4a, and decreased sirtuin-1 protein expression). This study demonstrated an impaired functionality of ECFCs at adulthood associated with arterial hypertension in individuals born after IUGR. 相似文献
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Nikolay N. Nityagovsky Konstantin V. Kiselev Andrey R. Suprun Alexandra S. Dubrovina 《International journal of molecular sciences》2022,23(10)
Recent investigations have shown the possibility of artificial induction of RNA interference (RNAi) via plant foliar treatments with naked double-stranded RNA (dsRNA) to silence essential genes in plant fungal pathogens or to target viral RNAs. Furthermore, several studies have documented the downregulation of plant endogenous genes via external application of naked gene-specific dsRNAs and siRNAs to the plant surfaces. However, there are limited studies on the dsRNA processing and gene silencing mechanisms after external dsRNA application. Such studies would assist in the development of innovative tools for crop improvement and plant functional studies. In this study, we used exogenous gene-specific dsRNA to downregulate the gene of chalcone synthase (CHS), the key enzyme in the flavonoid/anthocyanin biosynthesis pathway, in Arabidopsis. The nonspecific NPTII-dsRNA encoding the nonrelated neomycin phosphotransferase II bacterial gene was used to treat plants in order to verify that any observed effects and processing of AtCHS mRNA were sequence specific. Using high-throughput small RNA (sRNA) sequencing, we obtained six sRNA-seq libraries for plants treated with water, AtCHS-dsRNA, or NPTII-dsRNA. After plant foliar treatments, we detected the emergence of a large number of AtCHS- and NPTII-encoding sRNAs, while there were no such sRNAs after control water treatment. Thus, the exogenous AtCHS-dsRNAs were processed into siRNAs and induced RNAi-mediated AtCHS gene silencing. The analysis showed that gene-specific sRNAs mapped to the AtCHS and NPTII genes unevenly with peak read counts at particular positions, involving primarily the sense strand, and documented a gradual decrease in read counts from 17-nt to 30-nt sRNAs. Results of the present study highlight a significant potential of exogenous dsRNAs as a promising strategy to induce RNAi-based downregulation of plant gene targets for plant management and gene functional studies. 相似文献
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Wei Meng Yanli Li Binshu Chai Xiaomin Liu Zhongliang Ma 《International journal of molecular sciences》2022,23(15)
Lung cancer is the leading cause of cancer death worldwide. miR-199a, which has two mature molecules: miR-199a-3p and miR-199a-5p, plays an important biological role in the genesis and development of tumors. We collected recent research results on lung cancer and miR-199a from Google Scholar and PubMed databases. The biological functions of miR-199a in lung cancer are reviewed in detail, and its potential roles in lung cancer diagnosis and treatment are discussed. With miR-199a as the core point and a divergence outward, the interplay between miR-199a and other ncRNAs is reviewed, and a regulatory network covering various cancers is depicted, which can help us to better understand the mechanism of cancer occurrence and provide a means for developing novel therapeutic strategies. In addition, the current methods of diagnosis and treatment of lung cancer are reviewed. Finally, a conclusion was drawn: miR-199a inhibits the development of lung cancer, especially by inhibiting the proliferation, infiltration, and migration of lung cancer cells, inhibiting tumor angiogenesis, increasing the apoptosis of lung cancer cells, and affecting the drug resistance of lung cancer cells. This review aims to provide new insights into lung cancer therapy and prevention. 相似文献