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51.

Purpose

Long noncoding RNAs (lncRNAs) constitute an emerging group of noncoding RNAs, which regulate gene expression. Their role in cardiac disease is poorly known. Here, we investigated the association between lncRNAs and left ventricular hypertrophy.

Methods

Wild‐type and adenosine A2A receptor overexpressing mice (A2A‐Tg) were subjected to transverse aortic constriction (TAC) and expression of lncRNAs in the heart was investigated using genome‐wide microarrays and an analytical pipeline specifically developed for lncRNAs.

Results

Microarray analysis identified two lncRNAs up‐regulated and three down‐regulated in the hearts of A2A‐Tg mice subjected to TAC. Quantitative PCR showed that lncRNAs 2900055J20Rik and Gm14005 were decreased in A2A‐Tg mice (3.5‐ and 1.8‐fold, p < 0.01). We found from public microarray dataset that 2900055J20Rik and Gm14005 were increased in TAC mice compared to sham‐operated animals (1.8‐ and 1.4‐fold, after 28 days, p < 0.01). Interestingly, in this public dataset, cardioprotective drug JQ1 decreased 2900055J20Rik and Gm14005 expression by 2.2‐ and 1.6‐fold (p < 0.01).

Conclusions

First, we have shown that data on lncRNAs can be obtained from gene expression microarrays. Second, expression of lncRNAs 2900055J20Rik and Gm14005 is regulated after TAC and can be modulated by cardioprotective molecules. These observations motivate further investigation of the therapeutic value of lncRNAs in the heart.  相似文献   
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Clinical experience with a new electrical stimulation (ES) technique, the wireless micro current stimulation (WMCS), for the treatment of chronic wounds is described. WMCS transfers the current to any surface wound from a distance, by using oxygen's and nitrogen's ability to exchange electrons. We studied 47 patients with hard‐to‐heal wounds. Patients with venous, arterial and mixed leg ulcers were predominant; other aetiologies such as diabetic foot lesions, pressure ulcers, vasculitis and pyoderma were also included. WMCS treatment protocol specified treatment twice or thrice per week, for 45–60 minutes per session, with 1·5 μA current intensity. Standard wound care was applied to all patients, including compression bandages, if necessary. Clear progress of wound healing, even after 2 weeks, was observed in all cases. The mean reduction of the wound surface after WMCS treatment was 95% in 8 weeks. Complete healing was achieved within 3 months for the majority of the cases. No clinical side effects were observed. WMCS technology significantly accelerated wound healing for patients with hard‐to‐heal wounds of different aetiologies. This new therapy offers multiple advantages compared with the previous methods of ES, as it is contactless, free of pain and very easy to use.  相似文献   
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目的:分析温度对AH-Plus糊剂临床疗效的影响,为一次性根管治疗术中对温度的控制提供临床依据。方法:将48颗牙编号,按随机数字表法分为3组,采用AH-Plus糊剂在不同温度下对离体牙根管进行填充,使用染料渗入法检测微渗漏发生情况,用扫描电镜观察根管壁与封闭剂之间的结合情况。结果:1)在冠方微渗漏方面,不同温度下冠方微渗漏值均没有显著差异(P>0.05);2)在根尖微渗漏方面,C组(230℃)的根尖微渗漏显著小于A(150℃)、B组(180℃)(P<0.05),A、B两组的根尖微渗漏比较没有显著差异(P>0.05);3)扫描电镜对根尖区观察结果显示A组(150℃)的根管壁与牙胶之间缝隙明显大于B、C组。结论:在采用AH-PLUS热牙胶垂直加压技术充填根管时,设定热牙胶温度可能对根尖微渗漏产生影响,较高温度组(230℃)产生的根尖微渗漏小于较低温度组,冠方微渗漏无显著差异。  相似文献   
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目的:探讨micro RNA-9(mi R-9)过表达对β-淀粉样蛋白(Aβ)损伤的PC12细胞及B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关x蛋白(Bax)表达的影响。方法:PC12细胞分为mi R-9过表达组(E组)、空转染对照组(NC组)、不转染的损伤细胞模型组(NT组),采用CCK-8法检测细胞增殖;采用Annexin-V-PE检测细胞凋亡;采用RT-q PCR检测Bcl-2、Bax m RNA的表达,Western-Blot检测Bcl-2、Bax蛋白表达。结果:与NC组及NT组比较,E组的PC12细胞转染48 h后增殖增加,凋亡率降低,Bcl-2表达增加,Bax表达下降(P0.05)。结论:mi R-9过表达可保护Aβ损伤的PC12细胞。  相似文献   
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《Pancreatology》2014,14(2):117-124
PurposeIntraductal pancreatic mucinous neoplasms (IPMN) are precancerous cystic lesions. The aim was to investigate the in situ IPMN proteome using MALDI (Matrix-Assisted Laser Desorption/Ionisation) imaging and to characterize biomarkers associated with the grade of dysplasia.Experimental designFrozen human Branch duct -IPMN sections were selected according to dysplasia and proteomic analyses were performed by MALDI imaging to obtain mass spectra distribution. The most discriminating peaks were identified using tissue extraction and nanoLC-ESI-MS/MS. Identified peaks were validated in independent series of IPMN by immunochemistry on surgical specimens (tissue-microarrays (TMA), n = 45) and endoscopic ultrasound fine-needle aspiration (EUS FNA) samples (n = 25).ResultsBD-IPMN samples with low (n = 10) and high (n = 10) grades of dysplasia were analyzed. Differential spectra of proteins were found in the two groups with significantly different intensities (n = 15). The two peaks (intense in high grade IPMN) (m/z 8565 and 4747) were characterized as the monomeric ubiquitin (Mascot score = 319.22) and an acetylated fragment of thymosin-β4 (2–42) (Omssa score = 1.37 E−9). Validation on TMA and EUS FNA samples confirmed that ubiquitin was overexpressed in high grade dysplasia (p = 0.04 and p = 0.0004). Thymosin-β4 expression was confirmed on TMA by immunohistochemistry on high grade IPMN (p = 0.011).ConclusionUbiquitin and thymosin-β4 are overexpressed in IPMN with high grade dysplasia. Positive immunochemical staining on EUS-FNA material is a major argument in support of preventive resection.  相似文献   
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