尼美舒利对大鼠局灶性脑缺血/再灌注损伤的影响

目的　观察选择性环氧合酶 -2 (Cyclooxygenase -2 ,COX -2 )抑制剂尼美舒利 (nimesulide)对大鼠局灶性脑缺血 /再灌注损伤后神经功能缺陷、脑梗死体积及前列腺素E2 (PGE2 )含量的影响。方法　用线栓法制作大鼠脑缺血 /再灌注损模型 ,动物分别于缺血前 3 0min、再灌注后 6h、12h给予 3个不同剂量尼美舒利 ( 3、6和 12mg/kg ,ip)或等体积的溶媒。于再灌注后 6、12、2 4h进行神经功能评分 ;采用TTC染色法测定脑梗死体积 ;应用ELISA法检测PGE2 含量。结果　尼美舒利呈剂量依赖性减少脑梗死体积并改善功能预后 ,与溶媒组比较有显著性差异 (P <0 0 5 ) ;各尼美舒利治疗组脑梗死后PGE2 含量和溶媒组相比显著降低。结论　尼美舒利对缺血性脑损伤具有明显的保护作用 ,其保护作用可能与通过减少花生四烯酸环氧酶途径代谢产物抑制脑缺血后的炎症反应有关。     

葛根素对家兔脑缺血再灌注损伤的保护作用

目的 观察异黄酮类化合物葛根素对家兔全脑缺血再灌注损伤血浆内皮素及降钙素基因相关肽水平的影响.方法 健康家兔24只,体重2.0～2.5 kg,随机分为假手术组(A组)、缺血再灌注组(B组)和葛根素处理组(P组),8只/组.利用"六血管"模型阻断动脉30 min,恢复血流再灌注4 h.P组于缺血前10 min静注葛根素5 mg/kg,继之以微量泵150 μg·kg-1·min-1输注至实验结束,B组不用药.观察缺血前15min和再灌注4 h家兔血浆内皮素及降钙素基因相关肽水平.3组实验结束前取大脑皮层组织,伊红染色,光镜下观察其病理结构的变化.结果 B组血浆内皮素较A组显著升高,降钙素基因相关肽显著低于A组(P＜0.01);P组与B组比较血浆降钙素基因相关肽水平回升,而血浆内皮素水平显著低于B组(P＜0.01).光镜下,P组皮层轻度水肿、神经元核变性、固缩较少,核膜基本完整,核仁清楚;而B组皮层明显水肿,出血,有较多的核变性、溶解和固缩;A组皮层神经细胞基本正常.结论 葛根素能降低缺血再灌注期家兔血浆血浆内皮素含量,促进血浆降钙素基因相关肽的释放,减轻脑缺血再灌注损伤.     

远程缺血后适应对脑缺血损伤的实验研究

目的探讨远程缺血后适应对大鼠大脑中动脉缺血2h再灌注24h脑梗死体积、神经功能评分及Caspase-3表达的影响。方法大鼠脑缺血模型采用线栓法制备。缺血SD大鼠（280～300g）48只,随机分为假手术组（n=6）、对照组（即单纯脑缺血／再灌注损伤,n=14）和远程缺血后适应组（脑缺血后给予双下肢的非致死性的缺血再灌注）。根据后适应时间不同,后组者又分为缺血即刻后适应组（n=14）和再灌注即刻后适应组（n=14）。于大脑中动脉再灌注24h进行神经功能评分、脑组织梗死体积以及Caspase-3表达的测定。脑组织梗死体积采用四氮唑红（TTC）染色法测定。Caspase-3的表达应用免疫组织化学法检测。结果远程缺血后适应组的脑梗死体积与单纯缺血组相比明显降低,差异有显著性（P〈0．05）;与假手术组相比,单纯缺血组Caspase-3阳性细胞数明显增多,差异有显著性（P〈0．05）;与对照组比较,缺血即刻后适应组Caspase-3阳性细胞数降低,差异有显著性（P〈0．05）。结论远程缺血后适应能减轻脑缺血／再灌注损伤,其保护作用可能与降低Caspase-3的表达有关。     

L-NAME对SIM治疗脑缺血/再灌注损伤保护作用的影响

目的 研究一氧化氮合酶(NOS)抑制剂左旋硝基精氨酸甲酯(L-NAME)对辛伐他汀(Simvastatin，Sim)治疗脑缺血／再灌注损伤保护作用的影响。方法 ①采用Zea Longa法制作大鼠大脑中动脉阻塞(MCAO)模型。②54只雄性大鼠以辛伐他汀或其溶媒灌胃治疗2w，于MCAO手术前45min，经侧脑室注射L-NAME，MCAO 2h再灌注22h对大鼠进行神经功能缺陷评分，随后大鼠取脑制冠状切片，氯化三苯基四氮唑(TTC)染色后测量脑梗死体积。另取54只雄性大鼠操作同上，再灌注22h取脑制成匀浆，测量脑组织中乳酸(LA)、丙二醛(MDA)含量以及超氧化物歧化酶(SOD)活性。结果 辛伐他汀治疗可缩小大鼠MCAO后的脑梗死体积，改善神经功能。减少脑组织内LA和MDA生成，升高SOD活性，L-NAME可取消辛伐他汀的上述作用。结论 辛伐他汀对大鼠脑缺血／再灌注损伤有保护作用，L-NAME可取消这一作用，其机制可能与L-NAME抑制辛伐他汀上调eNOS基因表达和活化作用有关。     

内源性神经激肽和降钙素基因相关肽在大鼠心肌缺血后适应对心肌超氧化物歧化酶的作用

目的：研究神经激肽1（NK1）、降钙素基因相关肽（CGRP）在大鼠缺血后适应对心肌超氧化物歧化酶（SOD）的作用。方法：随机将SD雄性大鼠（350~400g）分为5组：sham组（只穿线不结扎冠状动脉）、I/R组（结扎冠状动脉左前降支30min,再灌注120min）、ipost组（结扎冠状动脉左前降支30min,再灌注10s夹闭10s,如此反复3次后持续再灌注120min）、CGRP8-37＋ipost组（结扎冠状动脉左前降支25min,按1μg/kg剂量从尾静脉给药CGRP8-37,5min行后处理再灌注同ipost组）、D-SP＋ipost组（结扎冠状动脉左前降支25min,按1μg/kg剂量从尾静脉给药D-SP,5min行后处理再灌注同ipost组）;快速液氮冷冻各组缺血心肌组织并提取心肌总蛋白,行总蛋白定量,用酶联免疫吸附技术检测心肌SOD的表达,分光光度法检测Caspase-3活性。结果：（1）与sham组比较,I/R组Caspase-3、SOD均增多（P〈0.01）;（2）与I/R组比较,ipost组SOD增多（P〉0.05）,Caspase-3减少（P〈0.01）;（3）与ipost组比较：CGRP8-37＋ipost组SOD降低（P〈0.01）,Caspase-3增多（P〉0.05）,D-SP＋ipost组SOD降低（P〈0.01）,Caspase-3增多（P〉0.05）。结论：神经激肽1降钙素基因相关肽（CGRP）通过上调缺血心肌SOD表达对缺血后适应心肌起保护作用。     

缺血预处理对家兔缺血再灌注损伤心肌的延迟保护作用

目的　探讨缺血预处理对家兔缺血再灌注损伤心肌的延迟保护作用。方法　 2 4只健康家兔 ,随机分为假手术组(Sham)、缺血再灌注组 (I/R)和缺血预处理组 (IP) ,每组 8只 ,分别预处理 2 4h后行心肌缺血 60min ,再灌注 12 0min ,观察缺血心肌形态结构变化、缺血区面积和危险区面积、血清腺苷 (Adenosine)、降钙素基因相关肽 (CGRP)含量。结果　I/R家兔部分心肌纤维断裂 ,有灶性出血 ,心肌间质大量炎性细胞浸润 ,血清腺苷和CGRP含量显著下降 (P <0 0 1) ;缺血预处理组部分心肌纤维呈波浪状 ,肌浆分布不匀 ,心肌间质无出血 ,有数量不等炎性细胞浸润 ,但心肌结构基本正常 ,仅少数线粒体有轻度水肿 ;并能显著缩小缺血再灌注损伤家兔心肌梗死危险区面积和心肌缺血梗死 ,血清腺苷和CGRP含量升高 ,与Sham组和I/R组比较 ,差异均有显著性意义 ( P <0 0 1)。结论　缺血预处理对家兔缺血再灌注损伤心肌有明显的延迟保护作用 ,其机制与腺苷和降钙素基因相关肽作用有密切的关系。     

右美托咪定对大鼠局灶性缺血再灌注脑组织线粒体通透性转换孔的影响

目的探讨右美托咪定对大鼠局灶性缺血再灌注脑组织线粒体通透性转换孔(m PTP)的影响。方法成年雄性SD大鼠45只,随机分为Ⅰ组(空白对照组)、Ⅱ组(缺血再灌注组)、Ⅲ组(右美托咪定组)各15只。采用线栓法阻塞大脑中动脉,然后恢复灌注,制备大鼠脑缺血再灌注损伤模型(MCAO),各组于脑缺血2 h后进行再灌注,再灌注22 h后处死大鼠,取脑组织,采用TTC染色法测定脑梗死体积,采用分光光度法测定线粒体mPTP开放程度。结果Ⅱ组和Ⅲ组的脑梗死体积比和mPTP开放程度高于Ⅰ组(P<0.05);Ⅲ组的脑梗死体积比低于Ⅱ组(P<0.05),Ⅱ组和Ⅲ组的mPTP开放程度比较无统计学差异(P>0.05)。结论右美托咪定可减轻大鼠局灶性缺血再灌注损伤,但对mPTP开放程度无明显影响。     

选择性COX-2抑制剂对大鼠局灶性脑缺血再灌注损伤的保护作用

目的观察诱导型环加氧酶（COX-2）抑制剂对大鼠局灶性脑缺血再灌注损伤（CIRI）的保护作用,探讨其可能机制。方法线栓法制备大鼠大脑中动脉闭塞2h/再灌注24h模型,治疗组在再灌注同时灌胃给予罗非昔布（Rofe-coxib）2.24mg/kg,对照组给予等容量生理盐水。免疫组化法测定脑组织中COX-2表达情况,用软件计算脑梗死面积,测定脑组织NO含量及NOS活性变化。结果 CIRI后脑组织COX-2表达增加,Rofecoxib 2.24mg/kg可有效抑制COX-2活性,能明显缩小脑梗死灶,降低NOS活性及NO含量。结论 Rofecoxib对大鼠局灶性脑缺血/再灌注损伤有保护作用。     

番茄红素对大鼠脑缺血再灌注损伤的影响

目的观察番茄红素(LP)对大鼠局灶性脑缺血再灌注损伤(I/R)及机体氧化应激水平影响的作用和机制。方法将大鼠分为5组,正常对照组、模型对照组、假手术组和两个实验组大鼠(分别每天灌胃5或20mg/kg番茄红素),15d后采用大脑中动脉栓塞法(MCAO)制备大鼠局灶性脑缺血/再灌注模型。分别在再灌注后第3h和第24h进行神经行为评分;再灌注24h后处死动物,计算脑梗死体积;测定脑组织一氧化氮(NO)、诱导型一氧化氮合酶(iNOS)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)及血清尿酸(UA)的含量及活性,并采用RT-PCR法检测脑皮质组织中低氧诱导因子(HIF)-1α mRNA、Bcl-2 mRNA的表达水平。结果与模型组比较,番茄红素组大鼠的脑梗死体积较小,神经症状较轻,脑组织SOD、CAT活性较高,iNOS活性及MDA、NO、血清UA的含量较低;与正常对照组相比,LP高剂量组HIF-1α mRNA表达上调;而Bcl-2 mRNA表达上调仅在LP低剂量组较为明显。结论番茄红素对大鼠的局灶性脑I/R损伤具有一定的保护作用,其机制可能与提高抗氧化酶活性,抑制脂质过氧化反应,降低iNOS活性,上调脑组织HIF-1α和Bcl-2水平有关。     

PPARγ激动剂对大鼠脑缺血再灌注损伤的保护作用

目的 研究过氧化物酶小体增殖剂激活型受体γ（PPARγ）激动剂吡格列酮对大鼠局灶性缺血再灌注脑组织的保护作用.方法 采用线栓法制作大鼠局灶性脑缺血再灌注模型（MCAO/R）,雄性SD大鼠60只随机分为假手术组、生理盐水干预组（NS组）、低剂量吡格列酮干预组（LDP组,10 mg/kg）、高剂量吡格列酮干预组（HDP组,15 mg/kg）.再灌注22 h后观察大鼠神经功能评分,采用2,3,5-氯化三苯基四氮唑（TTC）染色法测定脑梗死体积,常规HE染色观察脑组织病理变化.结果 与NS组比较,吡格列酮干预组（LDP组和HDP组）大鼠的神经功能评分明显降低、脑梗死体积缩小（P均＜0.05）,而且其脑组织神经细胞受损的程度下降,尤其以HDP组更为显著.结论 PPARγ激动剂吡格列酮对大鼠脑缺血再灌注损伤有保护作用,以大剂量组为优.     

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.     

The occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

The human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

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.     

Fatigue and health in a seafaring population

Background Occupational fatigue is relatively common withinthe general population and has been linked to reduced performance,injury and longer term ill-health. Despite growing acknowledgementof this problem in the maritime sector, little research hasbeen conducted into the risk factors, prevalence and consequencesof seafarers' fatigue. Aims To examine the prevalence of fatigue among seafarers, identifypotential risk factors and assess possible links with poor performanceand ill-health. Methods Cross-sectional questionnaire survey of seafarers workingin the offshore oil support, short-sea and deep-sea shippingindustries. A number of tools were used including the fatiguesubscale of the profile of fatigue-related symptoms, the CognitiveFailures Questionnaire, the General Health Questionnaire andthe SF36 General Health scale. Results In all, 1855 questionnaires were completed giving anoverall response rate of 20%. Fatigue symptoms were associatedwith a range of occupational and environmental factors, manyunique to seafaring. Reporting a greater number of risk factorswas associated with greater fatigue [e.g. OR = 2.53 (1.90–3.35)for those with three or four risk factors and OR = 9.54 (6.95–13.09)for those with five or more risk factors]. There was also astrong link between fatigue and poorer cognitive and healthoutcomes, with fatigue the most important of a number of riskfactors, accounting for 10–14% of the variance. Conclusions Seafarers' fatigue could impact on safety withinthe industry and may be linked to longer term individual ill-health.It can only be addressed by considering how multiple factorscombine to contribute to fatigue.     

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.