高脂肥胖大鼠血清瘦素,胰岛素及下丘脑细胞因子信号转导抑制因子-3基因表达的研究

目的观察高脂饮食肥胖大鼠血清瘦素,胰岛素水平及下丘脑细胞因子信号转导抑制因子-3基因(suppressors-of-cytokine-signaling 3,SOCS-3)表达变化及其关系,探讨高脂饮食肥胖大鼠引发瘦素抵抗及胰岛素抵抗的发生机制。方法以高脂饮食制备幼年雄性肥胖大鼠模型,采用放射免疫法检测各组大鼠血清瘦素、胰岛素及C肽浓度,葡萄糖氧化酶法检测血清葡萄糖水平,利用RT-PCR技术检测各组大鼠下丘脑SOCS-3基因表达水平。结果 (1)高脂饮食诱导的肥胖组大鼠体重明显高于对照组;(2)肥胖组大鼠血清瘦素、胰岛素,血糖及C肽水平明显升高,与对照组比较均有显著性差异;(3)肥胖组大鼠下丘脑SOCS-3的mRNA水平明显高于对照组;(4)肥胖组大鼠下丘脑内SOCS-3 mRNA水平分别与血清瘦素、胰岛素含量呈显著正相关。结论高脂饮食诱导的肥胖大鼠可出现瘦素抵抗和胰岛素抵抗以及SOCS-3基因表达上调。SOCS-3基因表达上调使瘦素及胰岛素受体后JAK-STAT信号转导通路抑制,可能参与了瘦素及胰岛素抵抗的发生机制。     

瘦素抵抗肥胖大鼠脂肪组织SOCS-3、PPARγ及ACO mRNA水平的探讨

目的观察高脂饮食诱导的肥胖瘦素抵抗大鼠细胞因子信号转导抑制因子-3(SOCS-3)、过氧化物酶体增殖物激活受体γ(PPARγ)及乙酰辅酶A氧化酶(ACO)mRNA表达水平的变化。方法30只Wistar雄性大鼠,6只为对照组喂饲基础饲料,24只为高脂组喂饲高脂饲料,第8周末按体重增量从高脂组中筛选出8只大鼠作为肥胖组,测定对照组和肥胖组大鼠血清瘦素,附睾脂肪组织中SOCS-3,PPARγ以及ACO mRNA表达。结果肥胖组大鼠体重以及血清瘦素水平均显著高于对照组(P<0.05);肥胖组脂肪组织SOCS-3、PPARγ mRNA水平显著高于对照组(P<0.05),而ACO mRNA则显著低于对照组(P<0.05)。结论高脂饮食诱导的肥胖大鼠存在瘦素信号转导通路的抑制,脂肪酸氧化能力降低,脂肪合成能力增强。     

大鼠重组瘦素对成熟脂肪细胞细胞因子信号转导抑制因子3表达的影响

目的模拟肥胖者体内高瘦素环境,探讨瘦素处理脂肪细胞细胞因子信号转导抑制因子3(SOCS-3)mRNA及蛋白表达变化。方法分离SD雄性大鼠附睾成熟脂肪细胞,RT-PCR法检测瘦素长型受体(OB-Rb)mRNA表达,并采用0.5～500nmol/L重组大鼠瘦素处理分离的成熟脂肪细胞0、0.5、2和6h,RT-PCR法检测SOCS-3 mRNA表达。免疫沉淀及Western blot检测SOCS-3蛋白表达。结果成熟脂肪细胞可表达少量的OB-Rb;未经瘦素处理的脂肪细胞SOCS-3 mRNA和蛋白只有少量表达,瘦素浓度0.5nmol/L时SOCS-3表达无明显变化,当瘦素浓度在5、50及500nmol/L时,SOCS-3表达量随时间延长而增加。结论瘦素可对脂肪细胞产生直接作用,并且可以诱导SOCS-3的表达增加。     

SOCS-3抑制对膳食诱导肥胖大鼠脂肪细胞PPARγ及aP2表达的影响

目的通过对膳食诱导肥胖大鼠脂肪细胞SOCS-3进行抑制,探讨是否可以恢复瘦素的抗脂肪合成作用。方法采用SOCS-3小发夹RNA（shRNA）慢病毒,感染瘦素抵抗肥胖大鼠成脂诱导分化后的脂肪细胞,检测SOCS-3的抑制效果。再采用50 nmol/L瘦素处理6 h,观察脂肪合成相关基因（PPARγ及aP2）mRNA表达的变化。结果 SOCS-3 shRNA慢病毒可有效抑制脂肪细胞SOCS-3 mRNA的表达,抑制率达50%。50 nmol/L瘦素处理6 h后,感染SOCS-3 shRNA慢病毒组PPARγ及aP2 mRNA的表达显著降低（P〈0.01）,空白对照组和感染阴性对照病毒组的表达无明显变化（P〉0.05）。结论通过抑制膳食诱导肥胖大鼠的脂肪细胞SOCS-3,在一定程度上可以解除脂肪细胞的瘦素抵抗。     

高脂饮食大鼠脂肪组织SOCS-3及FAS表达

目的 研究高脂饮食诱导产生的肥胖及肥胖抵抗大鼠脂肪组织细胞因子信号转导抑制因子-3(SOCS-3)及脂肪酸合成酶(FAS)的mRNA表达情况.方法 Wistar雄性大鼠31只,其中7只喂饲普通基础饲料作为对照组;24只喂饲高脂饲料,第8周末,按体重增量从高脂饲料组筛选出5只大鼠作为肥胖组,5只大鼠作为肥胖抵抗组.测定血清甘油三酯和总胆固醇,检测附睾脂肪组织SOCS-3及FAS的mRNA表达.结果 肥胖组大鼠血清甘油三酯及总胆固醇水平分别为(0.982±0.228),(2.213±0.364)mmol/L,均显著高于对照组大鼠的(0.717±0.153),(1.784±0.175)mmol/L(P<0.05),总胆固醇水平也显著高于肥胖抵抗组的(1.711±0.190)mmol/L(P<0.05);肥胖组大鼠的SOCS-3及FAS mRNA表达水平均显著高于对照组和肥胖抵抗组(P<0.05).结论 高脂饮食诱导产生的肥胖和肥胖抵抗大鼠在基因表达调控上可能存在差异,肥胖大鼠的生脂能力增强并可能存在瘦素信号转导通路的抑制.     

饮食诱导肥胖大鼠脂肪细胞对瘦素反应影响

瘦素具有促进脂肪分解、调节体重作用,但许多肥胖者血清瘦素水平增高,说明存在瘦素抵抗。细胞因子信号转导抑制因子3(suppressor of cytokine signaling-3,SOCS-3)可由瘦素诱导产生,而SOCS-3又可抑制瘦素信号通路。瘦素作用细胞     

瘦素受体基因变异研究进展

自1994年瘦素(Leptin)基因被定位克隆以来[1 ] ,瘦素及其受体与肥胖及其相关疾病如高血压、2型糖尿病、脂质代谢紊乱的关系成为近年来又一研究热点。人类的肥胖病患者大多表现为高瘦素水平,存在瘦素抵抗状态,因此瘦素受体(Leptinre ceptor,Lepr)作为瘦素调节机体摄食及能量代谢的信号传递中介受到高度重视。而研究瘦素受体多态性与能量代谢各指标的关系对于揭示肥胖及其相关疾病的共同遗传背景有着很重要的意义。本文就目前这方面的研究作一综述。1　瘦素受体基因结构及其变异人类的Lepr属细胞因子受体超家族,编码基因位于1p3 1,长约5 1Kb ,含2 0个外显子,19个内含子,编码1165个氨基酸[2 ] 。Lepr主要分布于大脑脉络丛、下丘脑、肝脏、肾脏、心脏、脾脏、睾丸、脂肪组织及胰岛细胞表面。Lepr按其结构可分为三个区:胞外区、跨膜区、胞浆区,根据其胞浆区的不同,Lepr基因转录后已知有5种(a～e)拼接型(splicedisoform) [3 ] 。除e拼接型外,其余4种均含有单一跨膜结构,通过Janus激酶-信号转导及转录激活蛋白途径促进细胞内基因的转录,参与体脂恒定的调节。Matss...     

中链甘油三酯饮食对神经肽Y及瘦素的作用研究

目的观察中链甘油三酯(MCT)对血清和下丘脑瘦素、神经肽Y(NPY)浓度,下丘脑长型瘦素受体(Ob-Rb)、mRNA表达的影响。方法20只Wistar雄性大鼠,用含30%MCT或长链甘油三酯(LCT)的饲料喂养8周,用ELISA法测定血清和下丘脑瘦素的水平,用放射免疫法检测外周血和下丘脑NPY的浓度,用real-time RT-PCR技术测定下丘脑NPY、瘦素受体(Ob-Rb)基因表达水平的差异。结果MCT组大鼠体重增长量和体脂含量均小于LCT组(P<0.01),MCT组瘦素脑/血比明显高于LCT组,MCT组大鼠下丘脑ob-Rb mRNA表达水平明显高于LCT组(P<0.01),下丘脑及血清NPY浓度明显低于LCT组(P<0.01)。结论MCT通过促进Ob-Rb基因表达,抑制NPY合成和分泌。     

饮食诱导肥胖小鼠瘦素及瘦素受体基因启动子甲基化探讨

【目的】探讨肥胖状态下小鼠瘦素及瘦素受体基因启动子区CpG位点的甲基化改变。【方法】使用30只3~4周龄C57BL/6J雄性小鼠,随机分为2组,每组15只,分别给予高脂饲料(脂肪含量34.9%,供能比为60%)和正常饲料(脂肪含量4.3%,供能比为10%)喂养3个月。喂养周期结束后,禁食、麻醉状态下心脏取血、脑组织和性腺周围脂肪组织。小鼠血浆中瘦素含量测定采用酶联免疫分析法;脂肪组织瘦素及下丘脑瘦素受体mRNA表达测定采用实时荧光定量PCR进行。最后应用亚硫酸盐修饰直接测序法(BSP)和半巢式PCR检测小鼠脂肪组织中瘦素基因启动子区(310 bp,-324到-29)16个CpG位点及脑组织中瘦素受体基因启动子区(294 bp,-633到-345)20个CpG位点的甲基化状态。【结果】高脂饲料诱导肥胖小鼠血浆瘦素含量[(5.95±3.34)μg/L]显著高于正常饲料组小鼠[(1.46±1.13)μg/L](t=4.888,P0.001)。脂肪组织瘦素mRNA表达量在肥胖小鼠(0.039±0.02)显著高于对照组(0.008±0.01)(F=12.945,P0.05);下丘脑瘦素受体mRNA表达在两组小鼠之间未见明显差异。脂肪组织中瘦素基因启动子区各CpG位点甲基化水平在60%~95%之间,而脑组织中瘦素受体基因启动子区各CpG位点呈现出高度去甲基化状态;在肥胖与正常小鼠之间,这两个基因启动子区CpG位点甲基化率均未见显著差异。【结论】瘦素基因及瘦素受体基因启动子区CpG位点甲基化可能与饮食诱导肥胖小鼠瘦素抵抗无关;肥胖状态下瘦素抵抗发生的机制仍有待于进一步研究。     

Trends in meningococcal disease in Italy in 1988

Meningococcal disease in Italy decreased 15% in 1988 from the previous year (290 vs. 342 cases). The decline was particularly evident in military cases (1.7/100,000 in 1988 vs. 5/100,000 in 1987) reflecting the full coverage of bivalent serogroup (A + C) meningococcal polysaccaride vaccine in army recruits, achieved since January 1988. The highest proportion of cases was seen in people older than 25 years of age (25%). Serogroup C constituted 60% of the isolates, while 19% belonged to serogroup B. The proportion of strains resistant to sulphonamides was 45%, while 15% were resistant to Minocycline and none to Rifampin. Out of the five military cases, only one (due to serogroup C) was attributable to the vaccine failure. A single coprimary case, but no secondary cases occurred among civilians. These findings are consistent with the trends reported in Italy in the previous years.     

Benzene in blood and phenol in urine in monitoring benzene exposure in industry

Determinations of benzene concentration in blood and of phenol in urine were made by head-space gas chromatography techniques on samples taken near the end of the work day from two groups of workers potentially exposed to low levels of benzene in the work-place atmosphere. Preliminary results suggest that benzene in blood is more reliable than phenol tests for assessing both exposure and uptake of benzene. Normal values of phenol in urine (10 mg/liter or less) were found in nearly all those cases in which benzene was detected in the blood.     

2015年郑州市饮用水放射性水平状况调查

目的了解郑州市不同地区、不同季节、不同水源类型的放射性水平。方法分别于丰水期和枯水期采集郑州市区黄河水源水、井水源水、丹江口水源水、出厂水和末梢水各一份;以县为单位,每单位采集出厂水、末梢水、水库水、河水、井水各1份,按《生活饮用水生活标准检验方法》(GB/T 5750.13-2006)检测饮用水中总α和总β放射性水平,依据《生活饮用水卫生标准》(GB 5749-2006)进行判定。结果丰水期、枯水期水体总α、总β放射性水平均低于国家标准限值。结论郑州市不同水源类型均处于正常的天然放射性本底水平。     

Occupational stress in nurses in psychiatric institutions in Taiwan

Nurses are known to be exposed to occupational stress. However, occupational stress is not well documented for nurses in psychiatric institutions in Taiwan. A cross-sectional study was conducted to explore the work-related stress and risk factors of nurses in psychiatric institutions in Taiwan. A structured questionnaire was distributed to nurses at five state-owned psychiatric hospitals in Taiwan in 2001. Demographic information, working environment, and personal health status were inquired. Occupational stress was assessed based on the Chinese version of Job Content Questionnaire (JCQ). General health status and mental health were evaluated by the International Quality of Life Assessment Short Form-36 (IQOLA SF-36). A total of 573 questionnaires were disseminated to nurses and 518 (90.4%) were satisfactorily completed by nurses, including 408 female full-time nurses who had been in their current work for more than 6 months. In the past one month, 17.2% of nurses reported being under significant stress often or always. Assault episodes were reported by 45.1% of nurses in the past 6 months. Among the nurses, 16.9%, 25.2%, 50.0%, and 7.8% belong to the "High strain", "Low strain", "Active", and "Passive" groups, respectively. Perceived occupational stress was associated with young age, widowed/divorced/separated marital status, high psychological demand, low workplace support, and threat of assault at work. Lower general health score was associated with low job control, high psychological demand, and perceived occupational stress. A lower mental health score was associated with low job control, high psychological demand, low workplace support, and perceived occupational stress. We concluded that nurses in psychiatric institutions are under significant stress related to work factors.     

Changes in nursing administration in supporting transplantation in Brazil

This historical and bibliographic study aimed to understand how Nursing was organized to support care in transplantation. The HISA, LILACS, BDENF, PERIENF and DEDALUS databases were consulted, and thirteen references were found, ten of which were scientific articles, two were master's dissertations and one was a doctoral thesis. The span of time chosen for study ranges from the date of the first kidney transplant in Brazil (1965), to the date of publication of the last scientific article found in the databases mentioned above (2003). After reading these articles, the ones that were similar in topic were grouped together, thus creating the thematic axis for the presentation of the results. The results showed that the Nursing profession has played an important and active role in transplants ever since the first procedure in 1965.     

2019年中国肿瘤流行病学研究进展

恶性肿瘤已成为中国居民的主要死因之一。近些年来,中国政府积极推进肿瘤预防和控制领域的研究工作,取得了很大的进步。本文简要汇总中国在肿瘤流行病学领域的研究进展,具体包括2019年的肿瘤负担、癌症危险因素及其干预、筛查和早期发现、癌症防治专项行动(2019-2022年)方案等方面,以期为我国肿瘤防治工作的有效开展提供技术支撑和理论依据。     

2012年绵阳市蔬菜中农药残留状况

目的 了解绵阳市2012年市售蔬菜中农药残留情况,为食用蔬菜监管提供依据.方法 全部样品均按照GB/T 5009-2003的方法进行农药的残留检测.依据GB 2763-2005《食品中农药最大残留限量》进行判定.结果 2012年共检测蔬菜165份,农药检出率和超标率分别为72.12％和23.64％.豆类、根茎类、叶菜类、瓜果菜类和食用菌类蔬菜检测农药残留超标率分别为8.00％、23.53％、36.00％、5.26％和27.03％,差异有统计学意义(x2=11.41,P＜0.01).不同种类农药超标率差异有统计学意义(x2 =62.42,P＜0.01).夏季和冬季蔬菜农药超标率差异无统计学意义(x2=3.44,P＞0.05).结论 绵阳市叶菜类蔬菜中农药残留情况较为严重,应采取有效措施,加强蔬菜的监督管理,从源头禁止高毒农药的使用,加大蔬菜种植、销售环节的监测,确保市民食用蔬菜的安全.