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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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ObjectivesDonor-specific cell-free DNA shows promise as a noninvasive marker for allograft rejection, but as yet has not been validated in both adult and pediatric recipients. The study objective was to validate donor fraction cell-free DNA as a noninvasive test to assess for risk of acute cellular rejection and antibody-mediated rejection after heart transplantation in pediatric and adult recipients.MethodsPediatric and adult heart transplant recipients were enrolled from 7 participating sites and followed for 12 months or more with plasma samples collected immediately before all endomyocardial biopsies. Donor fraction cell-free DNA was extracted, and quantitative genotyping was performed. Blinded donor fraction cell-free DNA and clinical data were analyzed and compared with a previously determined threshold of 0.14%. Sensitivity, specificity, negative predictive value, positive predictive value, and receiver operating characteristic curves were calculated.ResultsA total of 987 samples from 144 subjects were collected. After applying predefined clinical and technical exclusions, 745 samples from 130 subjects produced 54 rejection samples associated with the composite outcome of acute cellular rejection grade 2R or greater and pathologic antibody-mediated rejection 2 or greater and 323 healthy samples. For all participants, donor fraction cell-free DNA at a threshold of 0.14% had a sensitivity of 67%, a specificity of 79%, a positive predictive value of 34%, and a negative predictive value of 94% with an area under the curve of 0.78 for detecting rejection. When analyzed independently, these results held true for both pediatric and adult cohorts at the same threshold of 0.14% (negative predictive value 92% and 95%, respectively).ConclusionsDonor fraction cell-free DNA at a threshold of 0.14% can be used to assess for risk of rejection after heart transplantation in both pediatric and adult patients with excellent negative predictive value.  相似文献   
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Colorectal cancer (CRC) screening programs help diagnose cancer precursors and early cancers and help reduce CRC mortality. However, currently recommended tests, the fecal immunochemical test (FIT) and colonoscopy, have low uptake. There is therefore a pressing need for screening strategies that are minimally invasive and consequently more acceptable to patients, most likely blood based, to increase early CRC identification. MicroRNAs (miRNAs) released from cancer cells are detectable in plasma in a remarkably stable form, making them ideal cancer biomarkers. Using plasma samples from FIT-positive (FIT+) subjects in an Italian CRC screening program, we aimed to identify plasma circulating miRNAs that detect early CRC. miRNAs were initially investigated by quantitative real-time PCR in plasma from 60 FIT+ subjects undergoing colonoscopy at Fondazione IRCCS Istituto Nazionale dei Tumori, then tested on an internal validation cohort (IVC, 201 cases) and finally in a large multicenter prospective series (external validation cohort [EVC], 1121 cases). For each endoscopic lesion (low-grade adenoma [LgA], high-grade adenoma [HgA], cancer lesion [CL]), specific signatures were identified in the IVC and confirmed on the EVC. A two-miRNA-based signature for CL and six-miRNA signatures for LgA and HgA were selected. In a multivariate analysis including sex and age at blood collection, the areas under the receiver operating characteristic curve (95% confidence interval) of the signatures were 0.644 (0.607–0.682), 0.670 (0.626–0.714) and 0.682 (0.580–0.785) for LgA, HgA and CL, respectively. A miRNA-based test could be introduced into the FIT+ workflow of CRC screening programs so as to schedule colonoscopies only for subjects likely to benefit most.  相似文献   
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circRNA是一种新的内源性RNA,广泛存在于真核细胞中,参与转录或转录后基因表达调控,大部分属非编码RNA,是近几年RNA领域中的研究热点。circRNA主要通过拮抗miRNA来发挥“海绵作用”进而调控靶基因表达,与多种疾病有着密切联系,特别是在肿瘤中发挥重要作用。近年研究发现,circRNA对肝细胞肝癌(hepatocellular carcinoma,HCC)的发生、发展及转移具有重要调控作用。该文就circRNA与肝细胞肝癌关系的研究进展作一阐述。  相似文献   
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Background: miRNA 223 /125a and Cordon-bleu Protein Like 1 (COBLL1) are novel biomarkers that can predict prognosis and guide treatment decisions in patients with chronic lymphocytic leukemia (CLL). Also, there is a growing interest in CLL monitoring based on flow cytometry of receptor tyrosine kinase-like orphan receptor-1 (ROR-1).  Objective: This study aimed to evaluate the relationship between miRNA 223 /125a and COBLL1 expressions and ROR-1 expression in patients with CLL. Also, the study evaluated the relationship between the expression of these biomarkers with tumor staging and cancer progression. Methods: Our study included 40 patients newly diagnosed with B-CLL. In peripheral blood (PB), miRNA 223/125a and COBLL1 expressions were detected by real-time polymerase chain reaction (real-time PCR) and ROR-1 percentage was detected by flow cytometry before and after treatment.  Results: High level of COBLL1 expression was statistically significantly associated with high ROR-1 percentage expression (P= 0.03). However, a high level of miRNA 223/125a expression was statistically significantly associated with low ROR-1 percentage expression (P=0.002). The sensitivity and specificity of ROR-1 as a predictor of high WBCs count after treatment were 96.6 and 81.1%, respectively. There was a statistically significant reduction of ROR-1 percentage after treatment compared to before treatment (P <0.001). Conclusion: ROR-1 percentage expression can be considered a possible prognostic predictor in CLL along with miRNA 223/125a and COBLL1 expressions. This can be explained by the significant correlation between ROR-1 and the studied molecular biomarkers; miRNA 223/125a and COBLL1. In addition, there was a significantly higher ROR-1 percentage in patients with higher WBC counts. Moreover, there was a significant reduction in ROR-1 percentage after treatment.  相似文献   
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[摘要]?微小RNA (microRNA, miRNA)在宿主-病毒相互作用中起关键调节作用,参与HBV感染、复制和HBV相关疾病的调节。细胞miRNA可以通过直接结合HBV转录物或通过靶向与HBV生命周期相关的细胞因子间接调节HBV转录和复制。反过来,HBV感染也可以影响宿主细胞内的miRNA水平。HBV和miRNA之间的相互作用在HBV复制和HBV相关疾病的发病机制中发挥重要作用。本文对miRNA与HBV的相互关系进行综述,为进一步探讨HBV感染致病的分子机制和开发新的抗HBV治疗策略提供参考。  相似文献   
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Psoriasis is a chronic inflammatory disease, and microRNAs have been reported to regulate the pathogenesis of psoriasis. Up‐regulated miR‐744‐3p level was identified to associate with psoriasis while the precise functions of miR‐744‐3p in psoriasis were not well‐elucidated. We first confirmed the up‐regulation of miR‐744‐3p in psoriasis by measuring its expression level in psoriatic samples. We explored the roles of miR‐744‐3p on keratinocytes proliferation and differentiation. We searched the targets of miR‐744‐3p and evaluated the roles of one target, KLLN on keratinocytes proliferation and differentiation. We confirmed the up‐regulation of miR‐744‐3p in psoriatic samples. MiR‐744‐3p promoted keratinocytes proliferation while inhibited differentiation. MiR‐744‐3p targeted KLLN and overexpression of miR‐744‐3p resulted in decreased expression of KLLN. Overexpression of KLLN prevented the effects of miR‐744‐3p on keratinocytes proliferation and differentiation. MiR‐744‐3p regulated the proliferation and differentiation of keratinocytes through targeting KLLN in psoriasis.  相似文献   
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