人肽脱甲酰基酶基因pdf与肿瘤细胞生长的相关性

目的:研究人肽脱甲酰基酶(HsPDF)基因pdf在不同肿瘤细胞系中的表达情况并探讨该基因与肿瘤细胞生长的相关性。方法:体外培养肿瘤细胞,采用半定量RT-PCR方法检测不同肿瘤细胞系中pdfmRNA的水平;用HsPDF抑制剂Actinonin处理细胞并通过细胞形态学、MTT法、RT-PCR及凝胶电泳等技术检测pdf基因与肿瘤细胞生长的相关性。结果:RT-PCR结果表明,该基因在13种不同来源的人肿瘤细胞系和正常组织中的表达具有显著差异。其中,在Hela、MDA-MB-231、K562等肿瘤细胞系中高表达,而在人正常肺组织中低表达(P<0.001)。体外试验显示,Actinonin可显著地抑制肿瘤细胞的生长,使细胞中pdf基因表达量相应的下降,且呈明显的浓度依赖性;同时,光镜观察结果显示Actinonin对肿瘤细胞有诱导凋亡的作用。结论:pdf是一种广泛分布于不同组织的基因,它与肿瘤细胞的生长增殖间存在着显著的相关性。     

PBL联合PDG在临床医学系高年级医学生中的应用

目的 研究以问题为导向的教学方法 (PBL)联合问题—讨论—指导(PDG)教学模式在临床医学系高年级医学生培养中的应用效果.方法 选取2018年1月—2019年1月临床医学系高年级医学生134例,按随机数字表分为对照组(67例)与研究组(67例),对照组学生采用传统的教学模式,研究组学生采用PBL联合PDG教学模式,比...     

2020年器官移植免疫学实验研究进展

器官移植技术发展迅速, 但移植器官的长期存活和功能维持依旧离不开免疫抑制剂的大量使用。当前, 器官移植术后发生的排斥反应、感染等仍是移植科医师和受者需要面对的主要问题。为了进一步探究排斥反应和免疫耐受的基本生物学原理, 解答诸多临床器官移植过程中的病理生理学相关问题, 为器官移植更广泛、有效地推广应用提供基础理论依据和临床干预的指导, 器官移植领域的基础研究仍在稳步向前推进。2020年, 研究者在器官移植免疫应答基本规律、克服移植排斥反应、诱导移植免疫耐受等方面的基础研究有诸多重要进展。本文主要从免疫细胞亚群和免疫分子两大方向对2020年研究者诱导移植免疫耐受的部分新尝试和进展进行总结, 并简要展望了未来器官移植免疫学的主要发展方向。     

Meta-analysis of human lung cancer microRNA expression profiling studies comparing cancer tissues with normal tissues

ABSTRACT: BACKGROUND: Lung cancer is the major cause of cancer death globally, it is often diagnosed at an advanced stage and has one of the lowest survival rates of any type of cancer. The common interest in the field of lung cancer research is the identification of biomarkers for early diagnosis and accurate prognosis. There is increasing evidence to suggest that microRNAs play important and complex roles in lung cancer. METHODS: A meta-analysis was conducted to review the published microRNA expression profiling studies that compared the microRNAs expression profiles in lung cancer tissues with those in normal lung tissues. A vote-counting strategy that considers the total number of studies reporting its differential expression, the total number of tissue samples used in the studies and the average fold change was employed. RESULTS: A total of 184 differentially expressed microRNAs were reported in the fourteen microRNA expression profiling studies that compared lung cancer tissues with normal tissues, with 61 microRNAs were reported in at least two studies. In the panel of consistently reported up-regulated microRNAs, miR-210 was reported in nine studies and miR-21 was reported in seven studies. In the consistently reported down-regulated microRNAs, miR-126 was reported in ten studies and miR-30a was reported in eight studies. Four up-regulated microRNAs (miR-210, miR-21. miR-31 and miR-182) and two down-regulated mcroiRNAs (miR-126 and miR-145) were consistently reported both in squamous carcinoma and adenocarcinoma-based subgroup analysis, with the other 14 microRNAs solely reported in one or the other subset. CONCLUSIONS: In conclusion, the top two most consistently reported up-regulated microRNAs were miR-210 and miR-21. The results of this meta-analysis of human lung cancer microRNA expression profiling studies might provide some clues of the potential biomarkers in lung cancer. Further mechanistic and external validation studies are needed for their clinical significance and role in the development of lung cancer.     

The Vitamin D Receptor, Inflammatory Bowel Diseases, and Colon Cancer

The nuclear receptor is an emerging therapeutic target in various human diseases. Vitamin D receptor (VDR), a nuclear receptor, mediates the biological functions of vitamin D. Classically, vitamin D is recognized as an essential contributor to mineral and bone homeostasis. Increasing evidence demonstrates that vitamin D is involved in inflammatory responses. Persistent intestinal inflammation is associated with colon cancer. This review focuses on vitamin D and VDR in inflammatory bowel diseases and colon cancer. We place emphasis on the regulatory roles of vitamin D/VDR in inflammation, enteric bacteria, and tumorigenesis. We summarize the signaling pathways regulated by VDR in intestinal homeostasis. Finally, we discuss the potential application of the insights gleaned from these findings to personalized therapies in chronic inflammation and colon cancer.     

各向同性的3D T2 SPAIR SPACE序列在正常人肘部神经显像的应用

目的:观察磁共振3D T2 SPAIR (spectral adiabatic inversion recovery) SPACE序列在正常人肘部神经的显示情况,并观察其在不同人群中的显示差异?方法:在3.0 T MR下对64例正常人的2D FS-T2WI序列及3D T2 SPAIR SPACE序列平扫?对每个志愿者的3D T2 SPAIR SPACE序列的原始数据进行尺神经?正中神经及桡神经的曲面重建及最大密度投影重建,分别重建出矢状位及冠状位图像?分别统计3根神经的两种重建方法在上臂?肘关节及前臂的显示率?统计3根神经在2D FS-T2WI序列及3D T2 SPAIR SPACE序列上相对周围肌肉信号增高的比率? 结果:64例志愿者的尺神经?正中神经及桡神经在曲面重建上可以全部清晰显示?尺神经在上臂?肘关节及前臂的最大密度投影图像上的显示率分别为92%?83%?98%,正中神经在上臂?肘关节及前臂的最大密度投影图像上的显示率分别为81%?89%?80%,桡神经在上臂?肘关节的最大密度投影图像上的显示率分别为94%?95%?尺神经信号增高在2D FS-T2WI序列上为55%,而在3D T2 SPAIR SPACE序列上仅仅为30%?结论:3D T2 SPAIR SPACE序列对正常人的肘部神经显示效果好,对正常人尺神经信号增高显示更可靠?     

Discovery of Novel Small Molecule Mer Kinase Inhibitors for the Treatment of Pediatric Acute Lymphoblastic Leukemia

Ectopic Mer expression promotes pro-survival signaling and contributes to leukemogenesis and chemoresistance in childhood acute lymphoblastic leukemia (ALL). Consequently, Mer kinase inhibitors may promote leukemic cell death and further act as chemosensitizers increasing efficacy and reducing toxicities of current ALL regimens. We have applied a structure-based design approach to discover novel small molecule Mer kinase inhibitors. Several pyrazolopyrimidine derivatives effectively inhibit Mer kinase activity at sub-nanomolar concentrations. Furthermore, the lead compound shows a promising selectivity profile against a panel of 72 kinases and has excellent pharmacokinetic properties. We also describe the crystal structure of the complex between the lead compound and Mer, opening new opportunities for further optimization and new template design.