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目的 研究凉血通瘀方对高血压大鼠急性脑出血模型脑组织miRNA表达的影响,对差异表达的miRNA靶基因进行分析,探索凉血通瘀方可能的药效机制。方法 将自发性高血压大鼠随机分成对照组(B)和实验组(C)。适应性饲养一周后,C组灌胃凉血通瘀方,B组灌胃等体积生理盐水,连续5天,每天1次。构建脑出血模型后收集脑组织,借助全转录组测序技术获得miRNA表达量,与miRBase数据库比对获取已知miRNA,使用miRDeep2预测新miRNA。差异分析软件为DESeq2,筛选阈值为|log2FC| ≥1 并且P <0.05。对显著差异表达的miRNA进行靶基因预测,对靶基因进行GO功能、KEGG通路富集和PPI网络分析。结果 实验组和对照组对比,共发现21个显著差异表达的miRNA,上调有9个,下调有12个,共预测得到1243个有统计学意义的靶基因。GO富集分析发现,生物过程中突触囊泡分泌的调节、神经递质分泌的调节和神经递质运输的调节占前三位,神经元投射终点、全膜、质膜区域和细胞投射则是主要的细胞成分。分子功能分别为小GTPase绑定、底物特异性跨膜转运蛋白活性和离子跨膜转运体活性。通路分析结果显示,靶基因在癌证通路、pI3K-Akt信号通路、人类乳头瘤病毒感染、神经活性配体-受体相互作用和MAPK通路等分布广泛。采用STRING网站和Cytoscape软件,根据MCC算法筛选出ADRA2C、CASR、CCL28、CCR1、DRD2、GNAT3、GRM2、DYNC1LI1、GABBR1、GNAI1等核心靶基因。结论 凉血通瘀方对脑出血急性期鼠脑组织内miRNA的表达有重要影响;显著差异表达miRNAs可能通过靶向核心基因调控凉血通瘀方干预急性脑出血的病理过程及预后。  相似文献   
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Background

Clear cell renal cell carcinoma (ccRCC) is known to occur across the adult lifetime traversing the spectrum of age-related organismal changes. Little is known as to how the aging process may affect the course of renal cell carcinoma (RCC) and the repertoire of genes involved.

Methods

Using The Cancer Genome Atlas (n?=?436) and Cancer Genomics of the Kidney (n?=?89) datasets, we applied regression analysis to examine associations between patient age and gene expression profiles in ccRCC tumors and normal kidney tissues. Pathway enrichment analysis was performed to identify cellular process that is affected by aging in ccRCC. Moreover, connectivity mapping analysis was used to predict age-dependent response to drug treatments.

Results

Our analysis revealed different age-dependent gene expression spectra in ccRCC and normal kidney tissues. These findings were significant and independently reproducible in both datasets examined. Age up-regulated genes, showing higher expression in older patients, were significantly enriched (false discovery rate <0.05) in normal tissues for pathways associated with immune response and extracellular matrix organization, whereas age up-regulated genes in tumors were enriched for metabolism and oxidation pathways. Strikingly, age down-regulated genes in normal cells were also enriched for metabolism and oxidation, while those in tumors were enriched for extracellular matrix organization. Further in silico analysis of potential drug targets predicted preferential efficacy of Phosphoinositide 3-kinase inhibitor or immunotherapy in association with age.

Conclusion

We report on previously unrecognized associations between age and molecular underpinnings of RCC, including age-associated expression of genes implicated in RCC development or treatment.  相似文献   
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Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy.  相似文献   
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医改尚未成功,路在何方?   总被引:3,自引:0,他引:3  
目前我国医疗制度改革尚未取得成功,这与计划经济向市场经济转轨这历史时期及卫生工作的特殊性有关,出现问题,甚至失误,在所难免。提出(1)医改的目的是确保全国人民健康,人人享有医疗保健。(2)把卫生系统推向市场,医疗机构商业化,不是医改的方向。(3)预防为主,健全预防医学制系。(4)国家增加投入。(5)制定公立及私立医院各项制度,保护医务人员的合法权益。(6)加强社区基层医疗机构的建设。  相似文献   
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Objestive Systemic inflarmmation may be triggered by injury, hypothermia, ischemia-reperfusion and the contact of the blood with foreign body during cardiopulmonary bypass (CPB). To determine the application values of gene chip technique in the clinical practice and the study of cardiovascular stagery, as well as to provide clues to the study of inflammatory responess during CPB, microarry for gene expression profiles was used to identify the differences in the gene expression of myocardium between pre-and post- CPB. Methods Six adult patients who underwent CPB from March to May in 2003 were involved. Samples of right atrium were col- lected before and at immediate end of CPB. BD AtlasTM cDNA Expression Arrays was used to identify the differences in the gene ex- pression of cytokines. The results were compared with that of semi-quantative RT-PCR. Resellts The mean age of 6 patients (5 males and 1 female) was (32.67± 11.72) years. The baseline heart function was gradeⅡin 3 cases and grade Ⅲ in 3 other cases. The baseline left ventricular ejection fraction(LVEF)was (58.17±7.91)%. The mere duration was (91.67±43.88) minutes for CPB and was (58.67±43.46) minutes for aorta blocking. The minimum nasopharynx/rectal temperture was (29.37±1.90)℃/ (32.15±1.52)℃. Gene expression profiles of cytokines in the myocardium pre- and post-CPB were analysed successfully. The ex- pression of IL-6, IFN-γ,Wnt5a, TNFRSF1B, a member of tumor necrosis factor receptor superfamily, PIGF and MFNG in the myo- cardium were unpregulated after CPB. Conclusion Microarray technique is applicable in the study of cytokines changes dying CPB. cDNA microarray identified pleliminarily the differences in the gene expression between pre- and post-CPB. These genes may be in- valved in inflammation and other psthophysiological responses incuced by CPB. The myocardiym is probably one of the major sources of cytokines during CPB. Further study may be helpful in understanding the llngthe development of inflammation during CPB, and eventually, reducing the post-operative complications.  相似文献   
9.
Background and Aim:  We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods:  Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results:  Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion:  These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties.  相似文献   
10.
从感染病毒乳鼠脑组织提取总RNA,采用RT-PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中,通过脂质体介导转染COS-7细胞,用SDS-PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2-pcDNA3.1/His重组表达质粒,表达产物的相对分子量为56ku,与理论预期大小一致,并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2-pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有,能在哺乳动物细胞中表达并具有抗原性,重组质粒可应用于汉坦病毒的DNA疫苗研究。  相似文献   
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