5-氮胞苷对培养大鼠骨髓基质细胞β肌球蛋白重链表达的影响 骨髓干细胞移植与心肌修复的相关效应

目的研究5-氮胞苷(5-AZ)对体外培养大鼠骨髓基质细胞(BMSC)中心肌特异性β肌球蛋白重链(β-MHC)表达的影响,探讨骨髓基质细胞向心肌样细胞分化的条件。方法体外分离培养大鼠BMSC,用不同浓度5-AZ诱导培养,以RT-PCR方法测定诱导前后β-MHC的表达。结果正常培养大鼠BMSC不表达β-MHC。经5-AZ诱导24h并继续培养后,BMSC表达β-MHC,第1～4周内由1.89±0.37增至16.41±3.63(t=0.495～5.446,P<0.01=;(1×10-7)～(1×10-5)mol/L5-AZ使β-MHC的表达由7.30±1.77增至16.28±3.72(t=0.442～2.669,P<0.01)。结论5-AZ诱导体外培养大鼠BMSC表达心肌特异性β-MHC,与诱导时间及浓度呈正相关,提示可诱导大鼠BMSC向心肌样细胞分化。     

Gestational lead exposure induces developmental abnormalities and up-regulates apoptosis of fetal cerebellar cells in rats

Lead (Pb), a known environmental toxicant, adversely affects almost all organ systems. In this study, we investigated the effects of maternal lead exposure on fetal rat cerebellum. Female Sprague–Dawley rats were given lead nitrate in drinking water (0, 0.5, and 1%) for two weeks before conception, and during pregnancy. Fetuses were collected by caesarian section on gestational day 21 and observed for developmental abnormalities. The fetal cerebellar sections from control and 1% lead group were stained with cresyl violet. Immunohistochemical expressions of p53, Bax, Bcl-2, and caspase 3 were quantified by AnalySIS image analyzer (Life Science, Germany). Lead exposure induced developmental abnormalities of eyes, ear, limbs, neck and ventral abdominal wall; however, these abnormalities were commonly seen in the 1% lead-treated group. In addition, lead also caused fetal mortality and reduced body growth in both dose groups and reduced brain weight in the 1% lead-treated group. The fetal cerebella from the 1% lead-treated group showed unorganized cerebellar cortical layers, and degenerative changes in granule and Purkinje cells such as the formation of clumps of Nissl granules. An increase in Bax and caspase 3, and a decrease in Bcl-2 (p?相似文献   

Heavy chain diseases

Heavy chain diseases (HCDs) are rare B-cell lymphoplasma-cell proliferative disorders characterized by production of truncated monoclonal immunoglobulin heavy chains without associated light chains. HCDs involving the three main immunoglobulin classes have been described; alpha-HCD is the most common and has the most uniform presentation, gamma- and mu-HCDs have variable clinical presentations and histopathologic features. HCDs can be thought of as variant types of non-Hodgkin lymphoma: alpha-HCD presents as an extranodal marginal-zone lymphoma of mucosa-associated lymph-node tissue, gamma-HCD as lymphoplasmacytoid non-Hodgkin lymphoma, and mu-HCD as small lymphocytic non-Hodgkin lymphoma or chronic lymphocytic leukemia. Diagnosis of HCD requires documentation of a deleted immunoglobulin heavy chain without a bound light chain in the serum or urine. Prognosis is variable, and no standardized effective treatment programs are available except for alpha-HCD, which in its early stage may respond to antibiotics.     

活禽交易市场短期休市措施对控制市场H7N9病毒污染效果的评价

目的评估活禽交易市场短期休市措施对降低市场H7N9禽流感病毒污染及人感染H7N9发病的成效。方法收集整理2014年2月至2017年5月,中山市活禽交易市场短期休市信息、市场环境H7RT-PCR检测数据,及人感染H7N9发病数据。RRX=休市后第X周市场环境H7样本阳性率/休市前1周阳性率×100%。结果共实施3轮短期休市。第一轮:2014年2月10日至23日,期间周边地市未同步休市。恢复交易后,环境阳性率持续上升,RR1=0.40(95%CI:0.28-0.59),RR3=0.63(95%CI:0.32-1.24),RR4=0.83(95%CI:0.48-1.46),2015年5月份报告2例人感染H7N9病例。第二轮:2015年2月19日至28日,全省统一部署,周边地市同步休市。恢复交易后,环境阳性率持续维持在10%以下,RR1=0.15(95%CI:0.07-0.34),RR2=0.21(95%CI:0.10-0.41),RR3=0.03(95%CI:0.00-0.18),RR4=0.10(95%CI:0.04-0.27),该流行季未再报告病例。第三轮:2017年1月8日至21日,期间周边地市未同步休市。恢复交易后,环境阳性率持续上升,RR1=0.25(95%CI:0.09-0.68),RR3=0.37(95%CI:0.14-1.00),RR4=1.07(95%CI:0.54-2.11),2017年2月报告2例人感染H7N9病例。结论单个城市的短期休市,即使时间长达2周,一旦恢复交易,市场环境阳性率迅速上升,人感染发病的风险再次增加;区域性多个城市同步休市,市场环境阳性率能持续维持在低水平,极大地减少人感染发病的风险。     

Heat‐Stress effects on the myosin heavy chain phenotype of rat soleus fibers during the early stages of regeneration

Introduction: We investigated heat‐stress effects on the adult myosin heavy chain (MyHC) profile of soleus muscle fibers at an early stage of regeneration. Methods: Regenerating fibers in adult rats were analyzed 2, 4, or 6 days after bupivacaine injection. Rats were heat stressed by immersion in water (42 ± 1°C) for 30 minutes 24 hours after bupivacaine injection and every other day thereafter. Results: No adult MyHC isoforms were observed after 2 days, whereas some fibers expressed only fast MyHC after 4 days. Heat stress increased fast and slow MyHC in regenerating fibers after 6 days. Regenerating fibers expressing only slow MyHC were observed only in heat‐stressed muscles. Bupivacaine injection increased the number of Pax7⁺ and MyoD⁺ satellite cells in regenerating fibers, more so in heat‐stressed rats. Conclusion: The results indicate that heat stress accelerates fast‐to‐slow MyHC phenotype conversion in regenerating fibers via activation of satellite cells. Muscle Nerve 52 : 1047–1056, 2015     

Deletion of WASp and N-WASp in B cells cripples the germinal center response and results in production of IgM autoantibodies

Humoral immunodeficiency caused by mutations in the Wiskott-Aldrich syndrome protein (WASp) is associated with failure to respond to common pathogens and high frequency of autoimmunity. Here we addressed the question how deficiency in WASp and the homologous protein N-WASp skews the immune response towards autoreactivity. Mice devoid of WASp or both WASp and N-WASp in B cells formed germinal center to increased load of apoptotic cells as a source of autoantigens. However, the germinal centers showed abolished polarity and B cells retained longer and proliferated less in the germinal centers. While WASp-deficient mice had high titers of autoreactive IgG, B cells devoid of both WASp and N-WASp produced mainly IgM autoantibodies with broad reactivity to autoantigens. Moreover, B cells lacking both WASp and N-WASp induced somatic hypermutation at reduced frequency. Despite this, IgG1-expressing B cells devoid of WASp and N-WASp acquired a specific high affinity mutation, implying an increased BCR signaling threshold for selection in germinal centers. Our data provides evidence for that N-WASp expression alone drives WASp-deficient B cells towards autoimmunity.     

Predicting One-Year Mortality in Peritoneal Dialysis Patients: An Analysis of the China Peritoneal Dialysis Registry

This study aims to investigate basic clinical features of peritoneal dialysis (PD) patients, their prognostic risk factors, and to establish a prognostic model for predicting their one-year mortality. A national multi-center cohort study was performed. A total of 5,405 new PD cases from China Peritoneal Dialysis Registry in 2012 were enrolled in model group. All these patients had complete baseline data and were followed for one year. Demographic and clinical features of these patients were collected. Cox proportional hazards regression model was used to analyze prognostic risk factors and establish prognostic model. A validation group was established using 1,764 new PD cases between January 1, 2013 and July 1, 2013, and to verify accuracy of prognostic model. Results indicated that model group included 4,453 live PD cases and 371 dead cases. Multivariate survival analysis showed that diabetes mellitus (DM), residual glomerular filtration rate (rGFR), , SBP, Kt/V, high PET type and Alb were independently associated with one-year mortality. Model was statistically significant in both within-group verification and outside-group verification. In conclusion, DM, rGFR, SBP, Kt/V, high PET type and Alb were independent risk factors for short-term mortality in PD patients. Prognostic model established in this study accurately predicted risk of short-term death in PD patients.     

Sarcolipin and phospholamban as regulators of cardiac sarcoplasmic reticulum Ca2+ ATPase

The cardiac sarcoplasmic reticulum calcium ATPase (SERCA2a) plays a critical role in maintaining the intracellular calcium homeostasis during cardiac contraction and relaxation. It has been well documented over the years that altered expression and activity of SERCA2a can lead to systolic and diastolic dysfunction. The activity of SERCA2a is regulated by two structurally similar proteins, phospholamban (PLB) and sarcolipin (SLN). Although, the relevance of PLB has been extensively studied over the years, the role SLN in cardiac physiology is an emerging field of study. This review focuses on the advances in the understanding of the regulation of SERCA2a by SLN and PLB. In particular, it highlights the similarities and differences between the two proteins and their roles in cardiac patho-physiology.     

Determination of heavy metals in albumen of hen eggs from the Markazi Province (Iran) using ICP-OES technique

Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms.