沙棘籽油对大鼠溃疡性结肠炎组织的保护作用及其机制

目的研究沙棘籽油对葡聚糖硫酸钠(dextran sulfate sodium,DSS)诱导的大鼠溃疡性结肠炎组织损伤的保护作用,并初步探讨其作用机制。方法应用DSS制备大鼠溃疡性结肠炎模型。24只雄性大鼠随机分为正常对照组,DSS模型组和沙棘籽油干预3组。从造模开始,沙棘籽油干预组用沙棘籽油连续灌胃,其余两组等量蒸馏水灌胃。4w后处死所有大鼠,观察大鼠结肠组织大体形态,并进行组织学评分。生化法检测大鼠血清和结肠组织髓过氧化物酶(myeloperoxidase,MPO)、超氧化物歧化酶(superoxide dismutase,SOD)和谷胱苷肽过氧化物酶(glutathione peroxidase,GSH-Px)活性及丙二醛(malondialdehyde,MDA)含量。结果与DSS模型组相比,沙棘籽油组结肠MPO活性,降低血清和结肠MDA含量明显降低,血清和结肠SOD、GSH-Px活性升高,大鼠溃疡性结肠炎大体形态明显改善和组织学评分降低。结论沙棘籽油对DSS诱导大鼠溃疡性结肠炎有明显保护作用,抗氧化损伤可能是其作用机制。[营养学报,2012,34(4):349-352]     

乌司他丁对溃疡性结肠炎治疗的实验研究

目的：探讨乌司他丁对溃疡性结肠炎（UC）的治疗效果及其作用机制。方法：40只成年Wistar鼠，随机分为四组，正常组（A组）、溃疡性结肠炎组（B组）、柳氮磺胺吡啶（SASP）治疗组（C组）、乌司他丁治疗组（D组），用三硝基苯磺酸（TNBS）诱导实验性UC的大鼠模型，A、B二组用生理盐水处理大鼠。用药治疗2周后，分别观察各组血清中的肿瘤坏死因子α（TNF－α）、丙二醛（MDA）、超氧化物岐化酶（SOD）的变化以及病理学的改变。结果：乌司他丁、SASP可使实验性UC大鼠血清中的肿瘤坏死因子α、MDA、含量明显下降，SOD活性上升，并可明显减轻其结肠急性损伤程度及病理学的改变，且乌司他丁组疗效优于SASP组。结论：乌司他丁对UC有明显的治疗作用，其可能的机制为抑制炎性细胞因子的释放，清除自由基。     

雷公藤多甙对溃疡性结肠炎大鼠模型TNF-α和ICAM-1的影响

目的 探讨雷公藤多甙对大鼠溃疡性结肠炎炎性损伤的保护作用及可能机制。方法 采用三硝基苯磺酸（TNBS）制备大鼠溃疡性结肠炎模型，将动物随机分为正常对照组、模型组、生理盐水组及雷公藤多甙组4组。采用免疫组织化学染色检测肠组织TNF-α和ICAM-1表达，生化方法检测SOD、MDA和MPO含量，并观察肠道人体形态和组织学改变。结果溃疡性结肠炎模型组TNF-α、ICAM-1表达及MDA、MPO含量较正常组及生理盐水组显著增高，而SOD活性明显降低（P〈0．01），雷公藤多甙组TNF-α、ICAM-1表达，MDA、MPO含量明显低于溃疡性结肠炎模型组，SOD活性显著高于模型组（P〈0．01），雷公藤多甙组结肠炎性损伤评分指数叫显降低（P〈0．01）。结论 雷公藤对溃疡性结肠炎具有良好的保护作用，抗氧化及抑制炎性因子浸润可能是其主要的作用机制之一。     

多不饱和脂肪酸配比对溃疡性结肠炎大鼠影响

目的 探讨不同配比多不饱和脂肪酸(PUFA)对葡聚糖硫酸钠(DSS)诱导大鼠溃疡性结肠炎作用.方法 40只雄性SD大鼠随机分为对照组、DSS模型组及3个PUFA组(n-6/n-3为1∶1、5∶1、10∶1组)；用DSS建立大鼠溃疡性结肠炎模型,对照组和DSS模型组喂饲基础饲料,3个PUFA组分别给予不同比例PUFA饲料；观察大鼠粪便性状、腹泻及血便等一般状况；取结肠标本评价结肠湿重指数,生化法检测血清髓过氧化物酶(MPO)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量,ELISA法测定血清白介素-1β、6、10(IL-1β、IL-6、IL-10)含量.结果 与DSS模型组比较,5∶1 PUFA组结肠湿重指数[(79.90±13.84) mg/cm]和MDA含量[(3.52±0.65)nmol/mL]均降低(P＜0.05),血清SOD活性[(245.69±26.96) U/mL]升高(P＜0.01)；与1∶1、10∶1 PUFA组比较,5∶1PUFA组IL-1β和IL-6含量[(668.89±101.71)和(7.01 ±.4.21)pg/mL]均降低(P＜0.01),IL-10含量[(10.95±7.97)pg/mL]升高(P＜0.05).结论 膳食中n-6/n-3为5∶1时对大鼠溃疡性结肠炎有明显保护作用,其机制可能与抗氧化和抗炎作用有关.     

肌醇六磷酸对溃疡性结肠炎大鼠保护作用的实验研究

目的 研究肌醇六磷酸（IP6）对溃疡性结肠炎大鼠的保护作用,并初步探讨其作用机制。方法 48只雄性SD大鼠随机分为正常组、模型组、柳氮磺吡啶组、IP6低、中、高剂量组,采用葡聚糖硫酸钠诱导法构建溃疡性结肠炎大鼠模型,相应组分别以肌醇六磷酸钠0.5g/kg bw、1.0g/kg bw和2.0g/kg bw,柳氮磺吡啶0.5g/kg bw灌胃,连续10天。评估疾病活动指数（DAI）和结肠组织宏观损伤评分,结肠组织病理学观察,并检测结肠组织超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-PX）的活力,丙二醛（MDA）、肿瘤坏死因子α（TNF-α）和白细胞介素1β（IL-1β）的含量。结果 与模型组比较,柳氮磺吡啶组和IP6低、中、高剂量组DAI、结肠宏观损伤评分降低,差异有统计学意义（F=33.637,P<0.001;F=33.369,P<0.001）,组织病理学观察溃疡性结肠炎明显改善,且结肠组织中MDA、TNF-α和IL-1β含量均降低,差异有统计学意义（F=85.892,P<0.001;F=359.605,P<0.001;F=66.698,P<0.001）,IP6高剂量组SOD活力和GSH-Px活力最高,差异有统计学意义（F=7.073,P=0.001;F=40.812,P<0.001）,且随IP6剂量增加而升高。结论 IP6明显改善溃疡性结肠炎大鼠肠道病变,与IP6可抑制促炎因子,增强抗氧化作用有关。     

人乳脂对大鼠实验性结肠炎粘膜的保护

目的 探讨人乳脂质在肠道炎症中的作用机理及抗炎症特性。方法 予ＳＤ大鼠人乳脂质５周后，再用乙酸制做大鼠溃疡性结肠炎模型，观察乳脂对结肠炎粘膜的保护作用。结果 乳脂组能显著降低乙酸导致的大鼠结肠粘膜损伤指数和粘膜髓过氧化物酶，乳脂组的大鼠结肠组织血栓素含量，明显低于对照组；乳脂能提高大鼠组织超氧化岐化酶活性及ＶＥ含量，减少对机体有害的过氧化脂质含量。     

小檗碱对电离辐射损伤大鼠的保护作用及机制

目的 探究小檗碱（BBR）对电离辐射损伤大鼠的保护作用及机制。方法 把SD大鼠分为7组：正常对照组、1 Gy组、1 Gy低、高剂量BBR组（50,150 mg/kg）、3 Gy组、3 Gy低、高剂量BBR组（50,150 mg/kg）。除正常对照组外，各组大鼠进行医用电子直线加速器外照射，照后BBR灌胃给药，连续10 d。微量法测定大鼠血清超氧化物歧化酶（SOD）、还原型谷胱甘肽（GSH）和丙二醛（MDA）水平，HE染色法观察骨髓、小肠病理变化。结果 与正常对照组比较，辐射组大鼠血清MDA明显升高（P <0.05）,SOD、GSH明显降低（P <0.05），骨髓、小肠病理损伤加重。与辐射组比较，BBR组大鼠MDA血清水平明显下降（P <0.05）,SOD、GSH明显升高（P <0.05），骨髓、小肠病理损伤减轻，高剂量组更为明显。结论 小檗碱对辐射损伤大鼠具有一定的保护作用，机制可能是提高抗氧化物质的活性，增强对自由基的清除能力，从而减轻自由基造成的氧化损伤。     

1,25-(OH)_2D_3通过NF-κB通路对小鼠溃疡性结肠炎的影响

目的研究1,25-(OH)2D3对小鼠溃疡性结肠炎中核转录因子κB(nulear factor-κB,NF-κB)家族的影响,探讨其在小鼠溃疡性结肠炎中的作用。方法 6w龄雌性C57BL/6小鼠36只,随机分为正常对照组,溃疡性结肠炎模型组,1,25-(OH)2D3低、高剂量干预4组,除对照组外其余三组分别用葡聚糖硫酸钠(DSS)对小鼠进行溃疡性结肠炎造模,9d后处死小鼠,取血清和结肠组织。根据小鼠一般情况进行疾病活动指数(disease activity index,DAI)评分,观察小鼠结肠大体形态和病理学损伤情况,对其进行组织病理学评分。酶联免疫吸附法(ELISA)法检测小鼠血清TNF-α、IL-6含量,免疫组化测定结肠组织磷酸化IκB激酶β(phosphorylated inhibitor of nuclear factor kappa-B kinaseβ,p-IKKβ)、磷酸化核转录因子κB抑制蛋白α(phosphorylated inhibitor of NF-κB,p-IκB)、NF-κBp65蛋白表达情况。结果与DSS模型组比较,1,25-(OH)2D3干预组结肠组织IKKβ磷酸化减少,IκBα降解明显降低,NF-κB活化减少,小鼠血清TNF-α、IL-6含量下降,小鼠溃疡性结肠炎大体形态改善,组织学损伤较轻。结论 1,25-(OH)2D3可以通过抑制NF-κB通路,对小鼠溃疡性结肠炎起保护作用。     

小檗碱治疗大鼠免疫复合性溃疡性结肠炎及下调炎性细胞因子作用

目的探讨小檗碱(berberine,BER)对免疫复合性溃疡性结肠炎模型大鼠的作用及其与细胞因子的关系。方法健康SD大鼠64只,雌雄各半,随机分为正常对照组(12只)和模型组(52只);模型组应用免疫复合法(注射抗原乳化剂+TNBS/乙醇)建立溃疡性结肠炎大鼠模型,正常组注射生理盐水。再喂养3周后,随机从造模组中抽取4只处死,检查结肠病变情况,确定溃疡性结肠炎模型建立;随后将造模大鼠随机分为4组:BER低剂量组(0.1 g·kg-1),BER高剂量组(0.2 g·kg-1),柳氮磺吡啶(SASP)组(0.1 g·kg-1)和模型对照组;每组12只,每天灌胃给药1次,连续给药4周。每周观察大鼠疾病活动指数(DAI);末次给药后,处死动物,解剖观察并评定结肠黏膜损伤指数(CMDI);石蜡切片,HE染色,光镜下观察结肠组织的病理学变化,并做组织病理变化评分(HS);采用酶联免疫吸附剂测定(ELISA)方法测定血清IL-6、IL-8、IL-17、TNF-α水平变化。结果模型大鼠的DAI,CMDI,结肠HS评分均明显上升(P<0.01);血清中的IL-6、IL-8、IL-17、TNF-α含量明显上升(P<0.01);BER治疗4周后,使模型大鼠的DAI、CMDI、结肠HS评分均能显著下降(P<0.01),同时降低血清中IL-6、IL-8、IL-17、TNF-α的浓度(P<0.01)。结论 BER对免疫复合法诱致溃疡性结肠炎模型大鼠具有治疗作用,其机制可能与降低血清中IL-6、IL-8、IL-17、TNF-α含量及调节体内免疫反应有关。     

桦褐孔菌多糖对溃疡性结肠炎大鼠模型血清IL-6、IL-10的调节作用

目的：观察桦褐孔菌多糖对2、4、6-三硝基苯磺酸（rNBS）诱导的溃疡性结肠炎大鼠模型血清IL-6、IL-10的调节作用.方法：TNBS灌肠制备溃疡性结肠炎大鼠模型,造摸成功后用桦褐孔菌多糖灌胃治疗,14天后测大鼠血清内IL-6、IL-10的水平.结果：与模型组相比,IL-6含量明显降低（P＜0.05）;IL-10含量明显升高（P＜0.05）.结论：桦褐孔菌多糖可通过调节血清中细胞因子IL-6和IL-10在体内的水平,通过提高溃疡性结肠炎大鼠模型的免疫功能而达到治疗的作用.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.