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1.
Preeclampsia is a disease with a significant incidence worldwide that is directly associated with 15% of maternal deaths. This is usually characterized by the presence of hypertension and proteinuria, which manifests itself from the middle of pregnancy. MicroRNAs are single-stranded RNA molecules that act primarily by degrading transcribed messenger RNA or inhibiting microRNA translation. Placental microRNAs play a role in the growth and function of the placenta, their potential use as diagnostic biomarkers is considered feasible due to the ability to enter the maternal circulation and be detectable in maternal plasma.  相似文献   
2.
目的通过生物信息学分析筛选脓毒症诱导急性肺损伤(ALI)的关键基因。 方法从基因表达谱(GEO)数据库中下载GSE10474数据集,该数据集包含13例脓毒症ALI患者样本(ALI组)和21例脓毒症患者样本(脓毒症组)基因数据。使用limma包筛选两组样本的差异表达基因,并对筛选出的差异表达基因进行基因本体论(GO)功能分析及京都基因与基因组百科全书(KEGG)富集分析。通过STRING数据库构建蛋白质相互作用(PPI)网络并确定前10位hub基因。 结果从GSE10474数据集中共筛选出115个差异表达基因,其中65个上调基因,50个下调基因。GO分析显示,生物过程的基因主要富集在金属离子稳态、氧化应激、电离辐射等;细胞组分主要富集在液泡膜、高尔基体膜、内质网膜、溶酶体膜等生物膜;这些基因主要与生物跨膜、泛素结合酶活性、蛋白络氨酸、丝氨酸和苏氨酸激酶结合蛋白活性以及蛋白激酶抑制活性等分子功能相关。KEGG富集分析显示,差异表达基因主要富集在磷脂酶信号通路、胰岛素信号通路、T细胞介导的免疫反应以及免疫相关的信号通路。PPI网络图筛选出了前10位hub基因,分别为CD4、CD74、髓细胞核分化抗原(MNDA)、髓细胞触发受体1(TREM1)、人白细胞抗原DRA(HLA-DRA)、细胞附着蛋白1相互作用蛋白(CYTIP)、凝血因子XⅢA链(F13A1)、血清胱抑素F(CST7)、丝裂原激活蛋白激酶1(MAPK1)、细胞周期蛋白依赖性激酶抑制剂1A(CDKN1A)。 结论CD4、CD74、MNDA、TREM1、HLA-DRA、CYTIP、F13A1、CST7、MAPK1及CDKN1A是脓毒症诱导ALI的关键基因,可作为临床治疗和新药开发的新靶点。  相似文献   
3.
随着人类基因组测序、生物大数据信息分析、分子病理检测和人工智能辅助病理诊断等技术进步及其应用, 临床医学发展迈向精准诊疗时代。这一时代背景下, 传统诊断病理学迎来前所未有的历史机遇, 正在向"下一代诊断病理学(next-generation diagnostic pathology)"迈进。下一代诊断病理学以病理形态和临床信息为诊断基础, 以分子检测与生物信息分析、智慧制样与流程质控、智能诊断与远程会诊、病灶活体可视化与"无创"病理诊断等创新前沿交叉技术为主要特征, 以多组学和跨尺度整合诊断为病理报告内容, 实现对疾病的"最后诊断", 并预测疾病演进和结局、建议治疗方案和评估治疗反应, 形成新的疾病诊断"金标准"。未来, 需要激发病理学科创新活力, 加快下一代诊断病理学成熟和应用, 重塑病理学科理论和技术体系, 发挥诊断病理学在疾病"防、诊、治、养"等过程中的重要作用, 促进临床医学进一步发展, 服务健康中国战略。  相似文献   
4.
多原发肺癌(MPLC)在肺癌中相对少见。近年来随着人们对体检的重视以及影像学特别是高分辨率CT和PET/CT技术的发展, 越来越多的患者被诊断出多发性肺癌, 而区分多发性肺癌究竟是MPLC还是肺内转移显得尤为重要, 因为这直接关系到肿瘤的分期以及后续治疗的选择。本文根据现有文献对分子生物学检测在MPLC诊断上的研究进展进行综述, 旨在进一步加深对MPLC的认识, 提高MPLC的诊断水平。  相似文献   
5.
Background and Study AimsDubin–Johnson syndrome (DJS) is a benevolent genetic disorder of the liver with autosomal inheritance. It is a rare disorder characterized by an increase in conjugated bilirubin and anomaly in coproporphyrin clearance. DJS is caused by deleterious mutations in the ABCC2 gene. A polymorphism in the ABCC2 gene causes malfunctions in its ability to regulate the efflux of different organic anions, such as bilirubin, from hepatocytes to the canaliculi. Multidrug resistance protein 2 (MRP2) encoded by the ABCC2 gene is one of the main regulators of the export of bilirubin to respective sites. ABCC2 gene mutations have widely drawn attention in the pathology of DJS in various populations.Patients and MethodsThe ABCC2 gene was subjected to the National Center for Biotechnology Information (NCBI) database in 2020, and non-synonymous single-nucleotide polymorphisms (nsSNPs) and variants in untranslated regions were studied using different computational servers. SIFT, Protein variation effect analyzer, and PolyPhen-2 were used to retrieve the damaging Single-nucleotide polymorphisms (SNPs); PhD-SNP, SNPs&GO, and Protein Analysis Through Evolutionary Relationships were used to predict the association of nsSNPs with DJS; Mutation3D illustrated the location of variants in the protein; SNAP2, MutPred2, ELASPIC, and HOPE were used to predict the structural and functional effects of these mutations on MRP2; and I-mutant 3.0 and MuPro were used to determine the effects of polymorphism on the function of MRP2.ResultsIn this study, 18,947 SNPs were screened from the NCBI database, followed by a series of refinement of variants using online available servers. We concluded that 41 ABCC2 gene variants are vital etiological candidates for DJS in humans. These 41 variants had highly damaging effects on the MRP2 protein, which may lead to deficient transportation capacity, thereby affecting the efflux of bilirubin across the canalicular membrane.ConclusionIn silico tools are an alternative approach for predicting the target SNPs. Hence, previously unreported variants can be considered strong etiological candidates for diseases related to MRP2.  相似文献   
6.
《Acta histochemica》2022,124(4):151896
Gastric ulcer is a common frequent clinical problem affecting all age and gender. This work aims to compare between the therapeutic effects of stem cell derived exosomes, stem cells conditioned medium and omeprazole on the healing of gastric ulcer model.Fifty rats were, assigned into 5 groups; control, gastric ulcer, omeprazole-treated, conditioned medium- treated, and exosomes-treated groups. Gastric ulcer was induced by aspirin dissolved in 1% carboxymethyl cellulose at a daily dose of 200 mg/kg for 5 consecutive days. Stomach specimens were obtained for histological, biochemical, and immunohistochemical assessments.The gastric ulcer group revealed widening of the fundic glands lumen containing, exfoliated dead cells. There was a remarkable distortion of the normal histological structure of the gastric mucosa with surface lining epithelial cell sloughing, vascular congestion and inflammatory cell infiltration. Both exosomes and conditioned medium treatments ameliorated almost all of the histopathological changes. Interestingly, the healing effect of exosomes was greater because it restored the histological architecture of gastric mucosa to nearly normal.In conclusion, this work may pave the future for using stem cell derived exosomes as a more convenient and effective adjuvant therapy in gastric ulcer.  相似文献   
7.
Introduction: Cholangiocarcinoma (CCA) is the second most common type of primary liver cancer. Several factors, such as epigenetic changes in promoter genes, gene expression, and microRNAs (miR), can contribute to genomic instability in cancer. This study aimed at evaluating the expression of VEGF, miRs 145-3p, and 101-3p in patients with CCA and their potential as biomarkers for diagnosis and prognosis of CCA. Material and methods : Sixty two patients were studied. Out of these 62 patients, 41 cases had confirm CCA and 21 cases had hepatopathies complications. The RNA was extracted from a paraffined tissue block, and then the synthesis of cDNA was performed. The analysis of the expression of VEGF, miR-145-3p, and miR-101-3p was carried out by polymerase chain reaction in real time.  Results: The findings revealed that miRs 145-3p and 101-3p were under expressed in the case group compared to the control group (0.46; 0.17; P = 0.0001, respectively). VEGF was overexpressed in the case group compared to the control group (11.8; P = 0.0001). An increase in miR-145-3p expression level was observed in patients with perihilar CCA compared to those with distal CCA (0.51 ± 0.41; 0.17 ± 0.13; P = 0.0698). Survival rate analysis showed that 41.9% of patients with intrahepatic CCA and 31.5% of patients with extrahepatic CCA were free from death within 11 months, leading to a significant difference (P> 0.05). Conclusion: The underexpression of miRNAs, tumor suppressors, the overexpression of VEGF, smoking, and aging were associated with CCA based on our findings. It seems that the reduced expression of the studies miRNAs and increased expression of VEGF can contribute to a decrease in survival rate of patients with tumor in their intrahepatic bile ducts.  相似文献   
8.
肺炎是儿童常见的呼吸系统感染性疾病,也是导致儿童死亡的重要原因。选择高效而准确的检测方法,尽快明确病原体,对肺炎的诊断和治疗十分关键。近几年来,分子生物学技术获得了快速发展,许多新的技术逐步应用于临床,如实时荧光定量PCR、生物芯片、二代测序、核酸等温扩增技术等,极大的提高了肺炎病原体的检测效率。本文对以上技术的优缺点进行了简要介绍。  相似文献   
9.
目的探讨颅内动脉瘤Enterprise支架辅助弹簧圈栓塞后瘤腔和载瘤动脉的血流动力学改变。方法回顾性分析2021年3~8月Enterprise支架辅助弹簧圈栓塞治疗的24例颅内动脉瘤的临床资料。收集术前、术后即刻动脉瘤瘤腔和载瘤动脉处DSA数据的DICOM格式,导入OpenFOAM软件,应用计算流体力学数值模拟技术进行血流动力学分析,参数包括壁面剪切力(WSS)、均一化WSS(NWSS)、WSS分布梯度(WSSG)、流线方向WSSG(SWSSG)、归一化压力(NP)、剪切力震荡指数(OSI)。结果24例(24个动脉瘤)应用24枚Enterprise支架,术后即刻造影显示Raymond分级Ⅰ级18例,Ⅱ级6例。栓塞后WSS、NWSS、NWSS最小值、WSSG、WSSG最小值均明显升高(P<0.05),WSSG最大值明显降低(P<0.05)。结论Enterprise支架辅助弹簧圈栓塞治疗明显改变颅内动脉瘤的血流动力学,使载瘤动脉被重建、血流被重构,瘤腔内涡流减少或消失,血流形式由复杂转向简单。这些作用有助于瘤腔内血栓形成。  相似文献   
10.
Introduction: One of the major challenges in cancer treatment is the lack of specific and accurate treatment incancer. Data analysis can help to understand the underlying molecular mechanism that leads to better treatment.Increasing availability and reliability of DNA microarray data leads to increase the use of these data in a variety ofcancers. This study aimed at applying and evaluating microarray data analyzing, identification of important pathwaysand gene network for medulloblastoma patients to improve treatment approaches especially target therapy. Methods:In the current study, Microarray gene expression data (GSE50161) were extracted from Geo datasets and then analyzedby the affylmGUI package to predict and investigate upregulated and downregulated genes in medulloblastoma. Then,the important pathways were determined by using software and gene enrichment analyses. Pathways visualizationand network analyses were performed by Cytoscape. Results: A total number of 249 differentially expressed genes(DEGs) were identified in medulloblastoma compared to normal samples. Cell cycle, p53, and FoxO signaling pathwayswere indicated in medulloblastoma, and CDK1, CCNB1, CDK2, and WEE1 were identified as some of the importantgenes in the medulloblastoma. Conclusion: Identification of critical and specific pathway in any disease, in our casemedulloblastoma, can lead us to better clinical management and accurate treatment and target therapy.  相似文献   
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