乳酸杆菌对载脂蛋白E基因缺陷小鼠胆固醇代谢的影响

目的研究乳酸杆菌对apoE基因缺陷小鼠胆固醇代谢的影响。方法将apoE基因缺陷(ApoE-/-)小鼠随机分为4组:对照组(A组)、乳酸杆菌108cfu/ml组(B组)、乳酸杆菌1010cfu/ml组(C组)、乳酸杆菌1012cfu/ml组(D组)。A组喂养正常小鼠饲料(AIN-93),B、C、D组在正常饲料基础上添加108、1010、1012cfu/ml浓度乳酸杆菌喂养16周,检测小鼠血清、肝脏和主动脉中胆固醇的水平。结果乳酸杆菌可降低血清、肝脏和主动脉中总胆固醇(TC)的含量,提高血清中高密度脂蛋白胆固醇(HDL-C)的含量,与对照组相比差异具有统计学意义(P<0.05)。结论乳酸杆菌可改善apoE基因缺陷小鼠胆固醇的代谢。     

黑米皮抑制apoE基因缺陷小鼠T淋巴细胞表达

目的 研究黑米皮对载脂蛋白E(apoE)基因缺陷小鼠主动脉窦CD4^ 和CD8^ T淋巴细胞表达的影响，探讨黑米皮抗动脉粥样硬化(AS)作用的机制。方法 选用apoE基因缺陷小鼠进行实验，通过在apoE基因缺陷小鼠普通饲料AIN-93中添加5％黑米皮，检测apoE基因缺陷小鼠主动脉窦动脉粥样斑块面积和CD4^ 、CD8^ T淋巴细胞表达的水平。结果黑米皮可降低apoE基因缺陷小鼠主动脉窦动脉粥样斑块面积以及CD4^ T淋巴细胞表达的水平。结论 黑米皮的抗AS作用与其抑制CD4^ T淋巴细胞表达有关。     

载脂蛋白E基因敲除小鼠主动脉壁胆固醇含量的测定及意义

目的　探讨载脂蛋白E(apoE)基因敲除小鼠主动脉胆固醇含量的检测方法 ,并分析其对apoE基因敲除小鼠动脉粥样硬化斑块面积的评估价值。 方法　分离apoE基因敲除小鼠和正常小鼠主动脉 ,用酶法检测主动脉胆固醇的含量 ;用油红O染色法和图像分析法测量小鼠动脉粥样斑块面积。结果　apoE基因敲除小鼠主动脉胆固醇的含量显著高于正常小鼠 (P <0 .0 1) ,apoE基因敲除小鼠的动脉粥样硬化斑块面积也显著高于正常小鼠 ,且二者之间呈显著性相关 (相关系数r =0 .982 ,P <0 .0 1)。结论　apoE基因敲除小鼠主动脉胆固醇含量与其动脉粥样斑块面积的大小密切相关 ,是apoE基因敲除小鼠动脉粥样硬化斑块形成的一个重要指标。     

高胆固醇血症小鼠动脉粥样斑块中CHOP的表达

目的 通过高胆同醇血症诱发的小鼠动脉粥样硬化模型,对游离胆固醇通过激活未折叠蛋白反应诱导巨噬细胞凋亡的信号途径进行研究. 方法 C57BL6/J背景野生型和apoE基因缺陷小鼠各6只,分别使用普通饲料和高脂饲料分别喂养,13周后对两组动物的血脂分析,原位TUNEL染色观察巨噬细胞凋亡,并比较两组动脉组织中CHOP的蛋白表达. 结果高脂饲料喂养的apoE基因缺陷小鼠血脂水平显著高于对照组,尤以胆固醇的升高最为明显,并形成了严重的动脉粥样硬化;TUNEL染色显示动脉粥样病灶中有大量的巨噬细胞凋亡;免疫印迹实验表明动脉粥样硬化的组织中CHOP表达显著增高. 结论大量的游离胆固醇在巨噬细胞内聚集并通过激活未折叠蛋白反应诱导巨噬细胞凋亡,促进粥样斑块的形成.     

芝麻素对动脉硬化斑块形成及主动脉壁血管细胞黏附分子-1表达的影响

[目的]观察芝麻素对兔实验性动脉粥样硬化斑状形成的影响及主动脉壁血管细胞黏附分子-1表达的影响.[方法]将18只大耳白兔用基础饲料适应性喂养1周后,随机分成模型组(一次性耳静脉注射牛血清蛋白250mg/kg,每天喂饲高胆固醇饲料100g)、芝麻素组(一次性耳静脉注射牛血清蛋白250mg/kg,每天喂饲高胆固醇饲料100 g+芝麻素混悬液4mg/d灌胃)和对照组(一次性耳静脉注射生理盐水5 ml,每天喂饲基础饲料).各组测定0、5、8周末的血脂;实验结束时取主动脉,常规HE染色及免疫组织化学染色,观察主动脉形态学交化和血管壁斑块组织的变化;采用逆转录多聚酶链反应,凝胶图像分析系统扫描定量分析VCAM-1表达强度. [结果]芝麻素组血清胆固醇(TC)表低密度脂蛋白(LDL)显著低于模型组(P<0.01);主动脉病理改变和血管壁斑块组织免疫组化较模型组明显减轻(P<0.01);主动壁血管细胞黏附分子-1表达水平较模型组下调42.92%. [结论]芝麻素可降低动脉粥样硬化兔血清中TC和LDL水平,延缓或缩小其主动脉粥样斑块的形成,抑制或下调主动脉壁血管细胞黏附分子-1表达,具有降低血脂、预防和减轻动脉粥样硬化发生和发展的作用.     

红曲对ApoE~(-/-)小鼠肠道屏障功能影响

目的研究红曲对ApoE~(-/-)小鼠肠道屏障功能的影响。方法 6只雄性8周龄C57BL/6J小鼠作为正常对照组,18只8周龄雄性ApoE~(-/-)小鼠随机分为:动脉粥样硬化模型组;他汀对照组;红曲组。实验周期为12周。主动脉大体油红O染色,定量斑块面积;苏木精-伊红染色法(HE)观察结肠病理变化;透射电镜观察结肠超微结构变化;免疫印迹法(WB)检测结肠组织中紧密连接蛋白ZO-1、claudin-1的表达水平。结果正常对照组无斑块形成,动脉粥样硬化模型组斑块面积为(22.46±8.33)%。与正常对照组相比,模型组结肠绒毛高度和微绒毛长度[分别为(66.27±6.38)、(0.67±0.19)μm]降低(P 0.05);与模型组相比,红曲组结肠绒毛高度和微绒毛长度[(92.57±7.37)、(0.87±0.07)μm]均升高(P0.05)。与对照组相比,模型组结肠组织中claudin-1和ZO-1蛋白表达水平[分别为(494.00±47.15)、(466.67±43.41)]降低(P 0.05);与模型组相比红曲组claudin-1和ZO-1蛋白表达水平[(709.33±60.00)、(785.67±101.55)]均升高(P0.05)。红曲组所测各指标和他汀组相比均无显著性差异(P0.05)。结论红曲可以改善ApoE~(-/-)小鼠肠道屏障功能,其机制可能与修复结肠绒毛和通过上调结肠ZO-1和claudin-1紧密连接蛋白有关。     

肺炎衣原体感染促进APOE小鼠动脉粥样硬化研究

目的研究APOE小鼠肺炎衣原体感染后,对其动脉粥样硬化的形成是否有影响,为探索动脉粥样硬化的有效预防治疗途径提供依据。方法 48只APOE小鼠分为感染+高脂组、高脂组、感染组和对照组,每组各12只,喂养20周,进行血清抗CP抗体和血脂水平检测,油红O染色检测小鼠主动脉斑块形成面积。结果感染+高脂组、高脂组、感染组白介素-1β(IL-1β)、肿瘤坏死因子(TNF-α)的含量明显高于对照组(P<0.01);感染+高脂组IL-1β、TNF-α的水平明显高于感染组和高脂组(P<0.05);感染肺炎衣原体促进动脉粥样硬化斑块形成;油红O染色,感染组比对照组斑块面积均增加了25.0%,差异有统计学意义(P<0.01),感染+高脂组比高脂组斑块面积增加了23.0%,差异有统计学意义(P<0.01)。结论肺炎衣原体感染与高脂诱导和加速高脂饮食,促进APOE小鼠动脉粥样硬化的形成。     

甜菜碱对载脂蛋白E基因缺陷小鼠抗动脉粥样硬化的作用

目的 研究甜菜碱对载脂蛋白E(ApoE)基因缺陷小鼠动脉粥样硬化斑块形成的影响并对其抗炎机制进行初步探讨.方法 7周龄ApoE基因缺陷小鼠(品系C57BL/6J)按体重随机分为4组:模型组和3个甜菜碱组,同龄同品系野生型小鼠作为正常对照组.各组均喂饲AIN-93G基础饲料.3个甜菜碱组分别加入1%、2%、4%甜菜碱.于0、7、14周时测定血清肿瘤坏死因子-α(TNF-α)、单核细胞趋化蛋白-1、血脂水平以及主动脉TNF-α基因启动子的甲基化状况;于14周时测定主动脉窦脂质斑块占管腔面积百分比.结果 2%、4%甜菜碱组主动脉窦斑块面积占管腔总面积百分比分别为(11.43±2.65)%和(12.09 ±3.07)%,与模犁组(19.31±5.42)%相比差异有统计学意义(t值分别为3.117和3.010,P值均小于0.01);3个甜菜碱组血清TNF-α分别为(56.33±3.86)、(63.04±4.67)、(65.52±3.97)pg/ml,均明显低于模型组(79.40 ±4.68)pg/ml(t值分别为9.270、6.571、5.576,P值均小于0.001).结论 甜菜碱口J能通过抗炎作用而抑制ApoE基因缺陷小鼠动脉粥样硬化斑块的形成.     

小鼠动脉粥样硬化斑块中RGS5等基因的表达改变及黄芩素干预的实验研究

目的观察黄芩素对小鼠动脉粥样硬化(AS)模型斑块内RGS5等基因表达的影响。方法选用APOE-/-小鼠30只,体重18～22 g,随机分别对照组、模型组和干预组,每组10只,对照组给予APOE-/-普通饮食,模型组以高脂饲料喂养,干预组在高脂饮食中添加黄芩素(0.5%)。造模给药12周后,检测血脂,用Real Time-PCR方法检测对照组、模型组和用药组主动脉壁粥样硬化斑块中RGS5、PPARδ、MCP-1、NF-κB mRNA的表达。结果模型组血脂升高,斑块中RGS5 mRNA表达下调,PPARδ、MCP-1、NF-κB mRNA表达升高(P0.01)。黄芩素降低了高脂血症并逆转了上述基因表达,延缓了AS进程,差异均具有统计学意义(P0.05)。结论 RGS5等基因在AS的进程中具有重要的调控作用,黄芩素通过降低RGS5的表达,延缓AS的发生。     

虎杖苷经PI3K/AKT/FoxO1信号通路抗ApoE-/-小鼠动脉粥样硬化损伤研究

目的研究虎杖苷对ApoE^-/-小鼠动脉粥样硬化(Atherosclerosis,AS)损伤的影响;方法高脂喂养ApoE^-/-小鼠建立AS模型,随机分为:模型组、辛伐他汀组、虎杖苷组(n=8),另设8只C57BL/6J小鼠为对照组,给药12周后收集小鼠血清检测血脂水平;ELISA检测血清基质金属蛋白酶2和9(MMP2、MMP9)的含量;制作切片观察主动脉斑块;实时荧光定量PCR测PI3K、AKT、FoxO1转录水平;免疫印迹检测斑块PI3K、p-AKT、p-FoxO1蛋白水平;结果与模型组相比,虎杖苷组小鼠主动脉斑块显著减小,TC、TG与LDL-C浓度显著降低,MMP2和MMP9水平下调,而HDL-C浓度升高,PI3K、p-AKT表达水平显著升高,FoxO1磷酸化蛋白水平显著降低,差异有统计学意义(P<0.01);结论虎杖苷能显著减轻ApoE^-/-小鼠动脉粥样硬化损伤,可能与激活PI3K/AKT信号通路,从而抑制FoxO1磷酸化有关。     

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.     

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.     

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.     

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.