髋关节骨性关节炎软骨组织Col2a1和Nkx3．2的表达水平及临床意义

目的探讨髋关节骨性关节炎软骨组织中Ⅱ型胶原α1链（Col2a1）和人同源盒基因Nkx3．2的表达水平及临床意义。方法收集36例髋关节骨性关节炎患者的软骨组织样本,采用RT—PCR法检测Col2a1和Nkx3．2的mRNA水平,Westernblot法检测样本中两指标的蛋白水平;分析不同病理参数的Col2a1和Nkx3．2的mRNA和蛋白水平。并选取同期的39例股骨颈骨折患者作对照。结果髋关节骨性关节炎患者的Col2a1和Nkx3．2的mRNA和蛋白水平均高于股骨颈骨折患者（P〈0．05）;髋关节骨性关节炎患者两指标的mRNA和蛋白水平在年龄、类型、病程、ISOA、K—L放射线分级及严重程度上有统计学差异（P〈0．05或0．01）,在性别和侧别上无统计学差异（P〉0．05）。结论髋关节骨性关节炎软骨组织中Col2a1和Nkx3．2的表达水平上调,且在多数病理参数分布上有差异,提示两者在骨性关节炎软骨组织退变中起作用,可用于该疾病的诊断和治疗方案制订。     

DNMT1-mediated PTEN hypermethylation confers hepatic stellate cell activation and liver fibrogenesis in rats

Hepatic stellate cell (HSC) activation is an essential event during liver fibrogenesis. Phosphatase and tension homolog deleted on chromosome 10 (PTEN), a tumor suppressor, is a negative regulator of this process. PTEN promoter hypermethylation is a major epigenetic silencing mechanism in tumors. The present study aimed to investigate whether PTEN promoter methylation was involved in HSC activation and liver fibrosis. Treatment of activated HSCs with the DNA methylation inhibitor 5-aza-2′-deoxycytidine (5-azadC) decreased aberrant hypermethylation of the PTEN gene promoter and prevented the loss of PTEN expression that occurred during HSC activation. Silencing DNA methyltransferase 1 (DNMT1) gene also decreased the PTEN gene promoter methylation and upregulated the PTEN gene expression in activated HSC-T6 cells. In addition, knockdown of DNMT1 inhibited the activation of both ERK and AKT pathways in HSC-T6 cells. These results suggest that DNMT1-mediated PTEN hypermethylation caused the loss of PTEN expression, followed by the activation of the PI3K/AKT and ERK pathways, resulting in HSC activation.     

Associations between Consumption of Ultra-Processed Foods and Intake of Nutrients Related to Chronic Non-Communicable Diseases in Mexico

BackgroundUltra-processed foods are highly palatable and can be consumed anywhere at any time, but typically have a poor nutritional profile. Therefore, their contribution to total energy intake has been proposed as an indicator for studying overall dietary quality.ObjectiveThe aim of this study was to investigate the associations between the energy contribution from ultra-processed foods and the intake of nutrients related to chronic non-communicable diseases in Mexico.DesignThis study used a secondary analysis of cross-sectional data from the 2012 Mexican National Health and Nutrition Survey.Participants/settingThis study included participants aged 1 year and older (n=10,087) who had completed a 1-day 24-hour recall.Main outcome measuresIntake from added sugar (% kcal), total fat (% kcal), saturated fat (% kcal), protein (% kcal), dietary fiber (g/1,000 kcal), and dietary energy density (kcal/g) were measured.Statistical analysisMultiple linear regression models adjusted for sociodemographic variables were fitted to assess the association between quintiles of energy contribution from ultra-processed foods and nutrient intake.ResultsMean reported energy contribution from ultra-processed foods to the Mexican population’s diet ranged from 4.5% kcal in quintile 1 (Q1) to 64.2% kcal in quintile 5 (Q5). An increased energy contribution from ultra-processed foods was positively associated with intake from added sugar (Q1: 7.4% kcal; Q5: 17.5% kcal), total fat (Q1: 30.6% kcal; Q5: 33.5% kcal) and saturated fat (Q1: 9.3% kcal; Q5: 13.2% kcal), as well as dietary energy density (Q1: 1.4 kcal/g; Q5: 2.0 kcal/g) (P≤0.001); and inversely associated with intake from protein (Q1: 15.1% kcal; Q5: 11.9% kcal) and dietary fiber (Q1: 16.0 g/1,000 kcal; Q5: 8.4 g/1,000 kcal) (P≤0.001).ConclusionsIn the Mexican population, an increased energy contribution from ultra-processed foods was associated with a lower dietary quality with regard to intake of nutrients related to chronic non-communicable diseases. Future research is needed to identify barriers to eating a variety of unprocessed and minimally processed foods for the Mexican population, as well as effective public health strategies and policies to overcome these barriers.     

Diffusion MRI: Technical principles and application to uterine cervical cancer

Imaging is involved in the management of uterine cervical cancer with several objectives: 1/to assess local and lymph node extension of the initial disease; 2/evaluate treatment response to conservative therapy; 3/detect recurrences. Pelvic MRI is the first-line examination in all these indications. It is the key element for delineation after image fusion when the indication of chemoradiation therapy is made. It is also essential for guiding the placement of applicators and optimising the dosimetry of brachytherapy. The diffusion-weighted acquisition is a sequence sensitive to the motion of water molecules. It allows distinguishing water molecules with free diffusion from water molecules with diffusion restricted by obstacles such as cell membranes or the cytoskeleton. The diffusion is thus connected to the cellularity of the explored tissue, and the cancers, being hypercellular, will present a high signal. It thus provides additional information thanks to a high contrast between the tumour and the surrounding tissues, facilitating detection, evaluation of the volume and extent of the disease.     

化学合成 microRNA-21 inhibitors 对大鼠心肌成纤维细胞活化增殖的影响

目的：探究 microRNA-21 inhibitors 对大鼠心肌成纤维细胞活化增殖的影响。方法应用 LipofectamineTM 2000 Reagent 向大鼠心肌成纤维细胞瞬时转染 microRNA-21 in-hibitors 24、48 h 后,实时荧光定量聚合酶链反应(qRT-PCR)检测 microRNA-21、I 型胶原前胶原 A1(Col1A1)和α-平滑肌肌动蛋白(α-SMA)的表达水平;Western blot 法检测 Col1A1和α-SMA 的表达水平;MTT 法检测 microRNA-21 inhibitors对心肌成纤维细胞活化增殖的影响。结果转染 microR-NA-21 inhibitors 的心肌成纤维细胞中,microRNA-21表达下调,Col1A1和α-SMA 的表达下降;转染 microRNA-21 inhibi-tors 的心肌成纤维细胞增殖活性明显减弱。结论 microR-NA-21 inhibitors 可明显抑制心肌成纤维细胞增殖活性,提示microRNA-21是心肌成纤维细胞活化增殖的潜在靶向分子,有利于为干预和预防心肌纤维化的发生发展提供新思路。     

Mechanical arm with a universal clamp for intraoperative self-retaining holding of retractors and other equipment

A unique arm is described that attaches to the operating table and has a universal clamp. The arm will hold any retractor or other instrument in exactly the position and with exactly the pressure required. Suggestions for its use are given.     

A U.S. reference for human immunoglobulin E

The Committee on In Vitro Tests of the American Academy of Allergy has collected a large pool of human serum containing high titers of total lgE.for the purpose of establishing a U.S. reference material. This pool is free from hepatitis B surface antigen. The serum pool has been subaliquoted, lyophilized and tested.for total IgE content. The paper radioirnnuanosorbent test (PRIST) technique was used for this measurement. All laboratories used the same lot of reagents. The Second International Reference Preparation was used as the reference standard in each assay. Multiple replicates of the pooled sera were tested.for total IgE content with one set of reagents by each of the 14 participating committee laboratories. The results,for total IgE content (IU) of the vials were: mean of means, 899; median of means, 901; weighted mean. 898; it with an overall coefficient of variation of 15.3%. This new IgE re ference material is available to call laboratories for use as a primary reference standard from the Research Resources Branch, NIAID-NIH, Bethesda, MD 20205.