实验性脑出血大鼠脑内MMP-9mRNA表达作用的研究

目的动态观察实验性脑出血大鼠脑内血肿周围神经细胞凋亡情况和基质金属蛋白酶-9(MMP-9)表达水平的变化及其作用,探讨脑出血后血肿周围神经细胞损伤机制。方法健康雄性Wistar大鼠随机分为假手术组、生理盐水对照组(简称对照组)和脑出血模型组(出血组),分为术后6 h、12 h、24 h、48 h、3 d、5 d、7 d共7个时相点,采用尾状核注射自体非抗凝动脉血复制大鼠脑出血模型,对各组进行脑含水量的测定,进行TUNEL染色,通过免疫组织化学和原位杂交技术动态测定不同时间点鼠脑内血肿周围脑组织中MMP-9的表达变化。结果对照组及假手术组中各视野偶见TUNEL阳性细胞。脑出血后6 h有凋亡发生,以后逐渐增多,3 d达高峰后逐渐下降。出血组大鼠脑内注血后6 h开始出现脑组织水含量增加(P<0.05)。结论脑水肿及神经细胞凋亡参与了脑出血后继发性损伤的过程,实验性大鼠脑出血早期能诱导血肿周围MMP-9蛋白和mRNA表达增强,MMP-9可能参与了脑水肿的形成,并且与脑出血后细胞凋亡关系密切。     

脑出血后血肿周围神经元Cyt-c与Caspase-3的表达

目的观察大鼠脑出血后血肿周围神经元线粒体内细胞色素C(Cyt-c)与活化Caspase-3的表达情况,以探讨脑出血后神经元损伤的机制。方法用Ⅶ型胶原酶脑内立体定位注射诱导大鼠脑出血模型,免疫组化检测神经元线粒体内Cyt-C的释放与血肿周围活化Caspase-3的表达情况。结果大鼠脑出血后血肿周围神经元于6 h即有Cyt-C释放,出现胞浆染色的阳性细胞;1 d阳性细胞表达最多;3 d阳性细胞数减少;5 d阳性细胞继续减少,与假手术组比较差异明显(P<0.01);血肿周围于6 h出现Caspase-3阳性表达细胞,1 d阳性细胞计数达高峰,3 d出现轻度下降,5 d明显下降。与假手术组比较差异明显(P<0.01)。结论脑出血后血肿周围神经元Cyt-c与活化Caspase-3表达明显上调,Cyt-c与Caspase-3在脑出血后神经细胞凋亡中起重要调控作用。     

粒细胞集落刺激因子对脑出血大鼠血肿周围VEGF表达的影响

目的通过观察粒细胞集落刺激因子(G-CSF)对脑出血(ICH)大鼠血肿周围血管内皮生长因子(VEGF)表达的影响,探讨脑出血后G-CSF发挥神经保护作用的途径。方法 105只SD大鼠随机分为假手术组、ICH组和治疗组,每组各35只。断尾取自体血法制备ICH模型,造模1 h后治疗组经腹腔注射重组G-CSF(60μg/kg),假手术组、ICH组经腹腔注射等量等渗盐水。各组大鼠术后6 h、24 h、48 h、72 h、7 d、14 d、21 d进行神经功能障碍评分,处死大鼠,运用免疫组织化学方法检测血肿周围VEGF表达。结果治疗组大鼠从24 h开始各时间点神经功能障碍评分较ICH组明显增加(P0.05)。假手术组仅见少许VEGF表达;ICH组VEGF表达从6 h开始出现增多,7~14 d达到高峰;治疗组各时间点VEGF表达较ICH组明显增多(P0.05),72h~7d到达高峰。结论 G-CSF可能通过上调脑出血血肿周围VEGF表达发挥神经保护作用。     

实验性脑出血大鼠脑内MMP一9mRNA表达作用的研究

目的动态观察实验性脑出血大鼠脑内血肿周围神经细胞凋亡情况和基质金属蛋白酶9（MMP一9）表达水平的变化及其作用,探讨脑出血后血肿周围神经细胞损伤机制。方法健康雄性Wistar大鼠随机分为假手术组、生理盐水对照组（简称对照组）和脑出血模型组（出血组）,分为术后6h、12h、24h、48h、3d、5d、7d共7个时相点,采用尾状核注射自体非抗凝动脉血复制大鼠脑出血模型,对各组进行脑含水量的测定,进行TUNEL染色,通过免疫组织化学和原位杂交技术动态测定不同时间点鼠脑内血肿周围脑组织中MMP9的表达变化。结果对照组及假手术组中各视野偶见TUNEL阳性细胞。脑出血后6h有凋亡发生,以后逐渐增多,3d达高峰后逐渐下降。出血组大鼠脑内注血后6h开始出现脑组织水含量增加（P〈0．05）,3d达到高峰,然后逐渐消退。对照组和假手术组均无MMP一9蛋白和mRNA表达,出血组MMP一9蛋白及mRNA的表达与脑组织水含量及细胞凋亡的变化趋势一致,并且与脑含水量及细胞凋亡呈正相关（r=0．612,r=0．679,P〈0．01;r=0．671,r=0．735,P〈0．05）。结论脑水肿及神经细胞凋亡参与了脑出血后继发性损伤的过程,实验性大鼠脑出血早期能诱导血肿周围MMP9蛋白和mRNA表达增强,MMP一9可能参与了脑水肿的形成,并且与脑出血后细胞凋亡关系密切。     

肌苷对缺氧缺血性脑损伤后血管内皮生长因子表达的影响

目的研究肌苷对缺氧缺血性脑损伤后血管内皮生长因子（VEGF）表达的影响，探讨其神经保护作用机制。方法144只7日龄SD大鼠随机分为三组，即肌苷治疗组，缺氧缺血性脑损伤（HIBD）模型组和正常对照组，前两组参照Rice的方法建立HIBD模型。肌苷组在缺血缺氧后注射100mg/kg肌苷，2次/d，连续7d，HIBD模型组注射等剂量生理盐水，各组分别与缺血缺氧后6h、12h、1d、3d、7d、14d常规灌注取脑免疫组化检测VEGF。结果肌苷组VEGF表达比其他两组明显增多，且于1d、7d出现双峰曲线，14d基本恢复正常水平；HIBD组在缺血缺氧后1d达高峰，然后表达逐渐减少，3d时仅见少量阳性细胞表达，与正常组比较差异无统计学意义（P〉0.05）。结论肌苷可以促进VEGF的表达来发挥缺血缺氧性脑损伤的保护作用。     

大承气汤对脑出血大鼠神经元线粒体内细胞色素C释放的影响

目的观察大鼠脑出血后血肿周围神经元线粒体内诱导细胞凋亡的细胞色素C的释放,及中药大承气汤的干预作用。方法实验于2003-10/2004-3在中南大学湘雅医院中西医结合研究所完成。健康SD大鼠65只随机分成4组,分别为正常组(5只),假手术组(20只),模型组(20只),治疗组(20只)。除正常组外,其余3组设4个时间点6h,1d,3d,5d。每个时间点5只。采用免疫组化方法检测大鼠脑内血肿周围神经元线粒体内的细胞色素C的释放。结果65只大鼠进入结果分析。脑血肿周围组织细胞色素C阳性细胞计数正常组未见阳性细胞表达;假手术组仅于6h,1d时出现少数阳性表达细胞;造模后模型组血肿周围于6h出现阳性表达细胞,1d阳性细胞计数达高峰,3d出现轻度下降,5d明显下降。与假手术组比较差异明显(P<0.01)。大承气汤组与同时间点模型组比较6h计数无明显差异,1,3,5d均存在明显差别(P<0.05)。结论大鼠脑出血后血肿周围神经元线粒体内细胞色素C的释放明显上调;大承气汤能阻止细胞色素C释入胞浆,从而阻断凋亡信号进一步传导,保护脑出血后神经元。     

VEGF在局灶性脑缺血大鼠中表达规律的研究

目的探讨局灶性脑缺血大鼠模型中血管内皮生长因子（Vascular Endochelial Growth Factor,VEGF）的表达规律。方法制备大鼠局灶性脑缺血再灌注模型（Middle Cerebral Artery Occlusion,MCAO）,随机将实验大鼠分为两组：假手术（SH）组和手术（OP）组,OP组又分为再灌注6 h,12 h,1 d,3 d,7 d,14 d六个时间点。采用神经功能评分、TTC染色、光镜检测方法对模型予以评价。采用免疫组化技术观察再灌注不同时间点脑梗塞中心区及半影区VEGF及F8因子表达变化情况。结果 SH组无VEGF表达,OP组梗塞中心及半影区VEGF 6 h有表达,3 d达高峰期,7d后下降;而表达VEGF的新生血管内皮细胞3 d开始明显增多,7 d达高峰,14 d后下降。OP组F8因子（各大文献中均无F8因子的中文名字）在梗塞中心及半影区表达24 h开始减少并进行性下降,7 d周边区表达开始增加,14 d持续增多。结论 MCAO大鼠梗塞中心及半影区VEGF表达3 d达高峰期,7 d开始下降,而新生血管内皮细胞阳性表达出现晚,7 d达高峰;F8表达7 d开始增加,14 d持续增多。     

脑出血后血肿周围神经元Cyt-c与Caspase-3的表达及不同中医治法的干预

目的观察大鼠脑出血后血肿周围神经元Cyt-c与活化Caspase-3的表达情况及不同中医治法的干预作用。方法用Ⅶ胶原酶脑内立体定位注射诱导大鼠脑出血模型,免疫组化检测血肿周围神经元Cyt-c的释放情况与活化Caspase-3的表达,同时用直尺测量不同时间点血肿的最大直径。结果大鼠脑出血后血肿周围神经元于6h即有Cyt-c释放;1d后阳性细胞表达最多;3d后阳性细胞数减少;5d后阳性细胞继续减少,与假手术组比较差异明显(P<0.01);血肿周围于6h出现Caspase-3阳性表达细胞,1d阳性细胞计数达高峰,3d出现轻度下降,5d明显下降,与假手术组比较差异明显(P<0.01);采取不同中医治法治疗后Cyt-c与Caspase-3均有所下降,与其他各组比较,平肝熄风汤组治疗后下降最明显(P<0.01)。结论脑出血后血肿周围神经元Cyt-c与活化Caspase-3表达明显上调,采取熄风、泻火、祛痰、化瘀以及风火痰瘀同治等治法均能抑制Cyt-c与Caspase-3的表达,阻止神经元的凋亡,以平肝熄风汤组最为明显。     

ASPP1、VEGF在不同海拔地区大鼠脑组织中的表达及其与脑储备能力的关系

目的研究不同海拔高度和造模后不同时间点脑梗死大鼠脑组织中ASPP1、VEGF免疫组化的表达情况,评估在低压缺氧预处理后脑梗死大鼠的脑储备能力,探讨高原地区缺血性脑血管病脑储备能力的特点。方法采用免疫组化方法检测脑梗死大鼠脑组织中ASPP1、VEGF表达情况,根据染色深浅和阳性细胞比率评分进行统计学分析,比较不同海拔高度和造模后不同时间点的差异。结果 ASPP1在脑梗死后1 d和3、7、14 d,3 d和7、14 d,7 d和14 d比较以及海拔2 200 m和3 500 m,3 500 m和4 500 m比较,差异有统计学意义（P〈0.05）。VEGF在脑梗死后1 d和3、7、14 d 3 d和7 d,7 d和14 d,比较以及海拔2 200 m和3 500、4 500 m,3 500 m和4 500 m比较,差异有统计学意义（P〈0.05）。结论在中度海拔和高海拔地区适度低氧可以对抗细胞凋亡,在特高海拔和极高海拔地区能诱导细胞凋亡;在不同海拔高度低压缺氧预处理可以提高机体VEGF的表达水平,增强脑结构储备和脑代谢储备能力。     

脑白质损伤新生大鼠VEGF及iNOS表达变化研究

目的 研究缺氧缺血(HI)对新生大鼠脑白质细胞血管内皮生长因子(VEGF)及诱导型一氧化氮合酶(iNOS)表达的影响,探讨VEGF及iNOS在新生大鼠脑白质损伤(WMD)发病机制中的作用。方法 将3日龄大鼠随机分为实验组及假手术组,建立新生大鼠WMD模型,分别予HI后12、24、48、72 h及7 d处死,对其脑组织取材后行HE染色观察其病理改变,并应用免疫组织化学法检测其VEGF及iNOS的表达水平。结果 在新生大鼠脑白质中,1)VEGF表达水平予HI后12 h开始明显上升,24 h后达高峰,至7 d恢复正常,与对照组比较,实验组脑室周围白质VEGF的表达在12、24、48、72 h有统计学意义。2)实验组iNOS于HI后12 h表达开始增加,72 h达高峰,7 d仍有表达,与对照组比较,差异有统计学意义。 结论 HI可导致新生大鼠脑白质VEGF及iNOS的表达水平显著增高,参与新生大鼠WMD的病理生理过程。     

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.     

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.     

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.