异丙酚对大鼠胃缺血再灌注损伤的影响

目的观察异丙酚对大鼠胃缺血再灌注损伤（gastricischemia—reperfusion injury，GI—RI）的影响。方法30只SD大鼠，随机分为3组，假手术组（S组）、单纯缺血-再灌注组（I—R组）、异丙酚组（P组）。以夹闭大鼠腹腔动脉30min、松开动脉夹恢复血流灌注1h制备GI—RI模型。计算胃黏膜损伤指数，检测胃黏膜超氧化物歧化酶（supemxide dismutase，SOD）活性和丙二醛（malondialdehyde，MDA）含量。结果静脉注入异丙酚后，胃缺血再灌注导致的胃黏膜损伤减轻，胃黏膜损伤指数明显减少，异丙酚组（P组）与缺血一再灌注组（I—R组）比较，胃黏膜中MDA含量下降，SOD活性升高。结论异丙酚对GI—RI具有明显的保护作用。这种保护作用可能是通过异丙酚的抗氧化作用实现的。     

脑缺血再灌注Na～＋-K～＋-ATPase损伤作用的实验性治疗初探

目的：探讨尼莫地平和东莨菪碱治疗脑缺血再灌注损伤的作用机理。方法：夹闭双侧颈总动脉和椎动脉复制脑完全性缺血模型。60只家兔均分成六组,假手术组、脑缺血组、脑缺血再灌注组、脑低温治疗组、东莨菪碱治疗组、尼莫地平治疗组。采集脑和血液标本测量Na＋-K＋-ATPase、超氧化物歧化酶（SOD）、丙二醛（MDA）活性。结果：缺血再灌注组脑组织SOD和Na＋-K＋-ATPase活性降低、MDA含量升高;相反,治疗组SOD和Na＋-K＋-ATPase活性升高,MDA含量降低。结论：东莨菪碱和尼莫地平具有保护缺血再灌注组脑组织Na＋-K＋-ATPase活性的作用,其机理可能与它们抑制自由基介导的脂质过氧化,减少脂质过氧化物的生成有关。     

异丙酚对大鼠肺缺血／再灌注损伤的保护作用

目的研究异丙酚对肺缺血／再灌注损伤的保护作用。方法复制肺缺血再灌注损伤大鼠模型。将成年Wistar大鼠随机分为3组,A组为假手术组;B组为肺缺血一再灌注组,C组为畀丙酚组,每组15只。用酶联免疫吸附（ELISA）法检测支气管肺泡灌洗液（BALF）中TNF-α、IL-6的含量。同时对各纽动物血气和肺湿／干重比（W／D）进行检测。结果异丙酚能明显改善缺血再灌注动物的血氧分压,减少肺W／D值,降低BALF中TNF-α、IL-6含量。结论异丙酚抑制肺缺血再灌注时炎性细胞因子的表达,从而减轻细胞因子介导的炎性损伤,具有肺保护作用。     

疏血通对大鼠脑缺血再灌注后MDA、SOD的影响

目的本试验通过观察疏血通对超氧化物歧化酶、丙二醛的影响，探讨它的保护作用及作用机制。方法Wistor雌、雄性大鼠共30只，随机分为假手术组、盐水对照组及疏血通用药组，根据Koizumi线栓法建立大鼠左侧大脑中动脉缺血再灌注模型（MCAO）。24h断头取脑，同时检测脑组织中丙二醛（MDA）、超氧化物歧化酶（SOD）的含量。结果与盐水对照组组相比，疏血通治疗组光镜下病理损伤轻，脑组织中MDA含量降低、SOD含量升高。结论疏血通对大鼠脑缺血再灌注损伤具有保护作用，其机制可能与抑制自由基损伤有关。     

血塞通对大鼠脑缺血再灌注损伤保护的观察

目的：探讨血塞通注射液对大鼠脑缺血再灌注损伤的保护作用。方法：SD大鼠150只,雌雄不拘,采用Pulsinelli方法建立大鼠急性全脑缺血/再灌注型;按照随机数字表法分为三组,分别为假手术组,脑缺血再灌注组即对照组和血塞通组,分别于再灌注后3、6、12、24和48 h 5个时间点处死大鼠取出脑组织,每组10只。血塞通组于再灌注时给予血塞通注射液（5 mg/100 g）腹腔内注射后,其他组给予等容量的生理盐水（0.5 mL/kg）腹腔内注射后,均每间隔6 h等量注射;检测用于脑组织匀浆液的超氧化物歧化酶（SOD）、丙二醛（MDA）。结果：脑缺血再灌注期间,体内SOD减少,MDA增多,对照组与假手术组比较差异均有统计学意义（P〈0.01）,提示在脑缺血再灌注期间氧自由基大量生成而清除减少。而血塞通组与对照组相比较,SOD增多,MDA减少,两组比较差异均有统计学意义（P〈0.05）。结论：血塞通注射液对于大鼠脑缺血再灌注损伤具有保护作用,可减少氧自由基的产生。     

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。     

茶色素对脑缺血再灌注损伤大鼠一氧化氮合酶表达的影响

目的观察茶色素对大鼠脑缺血再灌注损伤的作用,并探讨其可能的保护机制。方法采用线栓法闭塞大鼠大脑中动脉建立脑缺血再灌注模型。雄性SD大鼠60只,随机分为缺血再灌注组、假手术组、银杏液组和茶色素组（50、100和200 mg/kg）。结果大鼠脑缺血再灌注后,梗死范围达23.5%±4.6%,神经症状评分增高为（2.8±0.4）分。中、高浓度茶色素可明显缩小脑缺血再灌注大鼠脑梗死范围（18.5%±3.6%和14.2%±2.9%）（P〈0.01）,高浓度茶色素可改善大鼠神经症状评分（1.9±0.3）分（P〈0.05）。与假手术大鼠比较,大鼠脑缺血再灌注后,脑组织MDA含量显著增加,SOD和GSH-Px活性明显降低。中、高浓度茶色素可降低脑缺血再灌注大鼠脑组织MDA含量,增加SOD和GSH-Px活性。大鼠脑缺血再灌注后,脑组织一氧化氮（NO）含量和诱导型一氧化氮合酶（iNOS）活性分别为（16.98±0.95）μmol/mg·prot和（3.89±0.23）U/mg.prot,明显高于假手术组的（6.12±0.39）μmol/mg·prot和（1.89±0.21）U/mg·prot（P〈0.01）,中、高浓度茶色素处理后可明显抑制NO含量和iNOS活性增高,NO分别为（14.26±1.21）和（11.25±1.07）μmol/mg·prot,iNOS分别为（3.45±0.22）和（2.85±0.25）U/mg·prot。结论茶色素可浓度依赖性地对抗缺血再灌注引起的脑损伤,其机制可能与抑制iNOS诱导的NO产生增加有关。     

LMWH-SOD对沙土鼠全脑缺血再灌注后TNF-a表达的影响

目的观察低分子肝素-超氧化物歧化酶(LMWH-SOD)对沙土鼠脑缺血再灌注脑组织肿瘤坏死因子α(TNF-α)表达的影响,探讨LMWH-SOD脑保护作用机制。方法健康沙土鼠48只,随机分为假手术组、生理盐水组、低分子肝素(LMWH)组、超氧化物歧化酶(SOD)组、LMWH与SOD联合(LMWH SOD)治疗组和LMWH-SOD组。建立沙土鼠全脑缺血再灌注损伤模型,采用免疫组织化学染色法检测脑缺血10 m in再灌注6 h沙土鼠脑组织内TNF-α表达的变化。结果脑缺血再灌注后脑组织内TNF-α的表达明显升高;与生理盐水组比,各用药组TNF-α阳性细胞数明显减少(P<0.01),细胞染色明显变浅;而LMWH-SOD对TNF-α表达的抑制最为显著,阳性细胞数减少最为明显,与其它用药组比较差异有统计学意义(P<0.01),细胞着色也较浅。结论LM-WH-SOD对脑缺血再灌注损伤有保护作用,其脑保护机制可能与抑制炎性细胞因子TNF-α的过度表达有关。     

硒对沙土鼠脑缺血再灌注的保护作用及其作用机制研究

目的 研究亚硒酸钠对沙土鼠脑缺血再灌注损伤的保护作用及其机制。方法 将50只沙土鼠随机分为5组，Ⅰ组：假手术组；Ⅱ组：缺血灌注1天处死组；Ⅲ组：缺血再灌注4天处死组；Ⅳ组：硒处理、缺血再灌1天处死组；Ⅴ组：硒处理、缺血再灌注4天处死组。采用夹闭双侧颈动脉法制备沙土鼠脑缺血再灌注模型，焦油紫染色，光镜下观察各组海马CAl区神经细胞的形态变化，电镜下超微结构变化。同时测定脑组织中丙二醛(MDA)、谷胱甘肽过氧化酶(GSH-PX)、超氧化物歧化酶(SOD)的含量。结果 硒处理组沙土鼠脑缺血再灌注后，神经细胞病理形态损伤较轻，SOD、GSH-PX含量较高，MDA含量较低。结论 硒对沙土鼠脑缺血再灌注损伤具有保护作用，其机制可能和增强脑缺血再灌注早期脑组织中SOD、GSH-PX的活性，抑制氧自由基损伤，减轻脂质过氧化反应有关。     

紫菜多糖对脑缺血再灌注损伤保护作用的实验研究北大核心CSCD

目的研究紫菜多糖(PP)对反复脑缺血/再灌注损伤小鼠的作用。方法采用反复夹闭双侧颈总动脉再灌注法造模,采用避暗法实验测试灌胃给予PP(100、200、400 mg/kg)7 d后对学习记忆障碍的改善作用,同时测定脑组织匀浆中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)及血浆中白细胞介素1β(IL-1β)、IL-6和IL-10的水平,采用透射电镜观察小鼠脑神经元超微结构。结果 PP能明显延长小鼠潜伏期,减少错误次数,提高脑组织SOD含量和GSH-Px活性,降低MDA含量,同时降低血浆IL-1β、IL-6的水平,升高IL-10的水平,连续7 d灌胃给药PP可以显著改善脑缺血再灌注造成的脑神经元损伤。结论 PP对反复脑缺血/再灌注损伤小鼠有保护作用,可能与其抗氧化、降低炎症反应、改善神经元损伤有关。     

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.     

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.     

Assessing occupational and environmental exposure

Exposure assessment is a poorly understood component of the science of epidemiology. The relationship between exposure to chemicals and ill-health outcomes is often calculated using crude exposure measures such as ever/never exposed or duration. When investigating subtle effects, exposures need to be characterized much more fully in terms of intensity, frequency, duration and route. While occupational exposures tend to be much greater than those experienced from the wider environment there is a need to remember that, for many chemicals, exposure can occur occupationally, environmentally and through consumer use of products containing the material of interest. Inhalation exposure has generally been the traditional focus for most epidemiological investigations but there is now growing awareness of the importance of the dermal and ingested routes of contact and internalization. Quantification of the exposure also needs to be related to a biological mechanism of action and exposure metrics need to be selected accordingly. Occupational exposures can generally be measured using simple well-validated techniques. Environmental exposures require much more sensitive instruments and are more difficult to assess. Exposure modelling, particularly for the environmental fate of chemicals has undergone many recent developments and Monte Carlo techniques can be used to characterize model uncertainty and variability. This approach to exposure assessment can now be used in the setting of the wider environment and will enable a far better understanding of the relationship between exposure and disease.     

Mercury toxicity due to the smelting of placer gold recovered by mercury amalgam

A 19-year-old man developed tremor in both hands and fatigue after starting work at a placer gold mine where he was exposed to mercury-gold amalgam. Examination revealed an intention tremor, dysdiadochokinesis and mild rigidity. The 24-h urinary mercury concentration reached a peak of 715 nmol/l (143 ug/l) shortly before the clinical examination, after which he was removed from working in the gold room [Mercury No. Adverse Effect Level: 250 nmol/l (50 ug/l)]. On review 7 weeks later his tremor had almost resolved and the dysdiadochokinesis and rigidity had gone. The 24-h urinary mercury concentration had fallen to 160 nmol/l (32 ug/l). The principal exposure to mercury was considered to be the smelting of retorted gold with previously unrecognized residual mercury in it. The peak air concentration of mercury vapour during gold smelting was 0.533 mg/m3 (Mercury Vapour ACGIH TLV: 0.05 mg/m3 TWA). Several engineering and procedural controls were instituted. This episode occurred at another mine site, unrelated to Mount Isa Mines Limited.     

How Adults with Acquired Brain Damage Perceive Computer Training as a Rehabilitation Tool: A Focus-group Study

The aim of this study was to explore and describe how adult outpatients with acquired brain damage and referred to occupational therapy perceive computer training with the RehaCom programs, in order to evaluate the method of treatment as a tool in the rehabilitation of persons with cognitive disorders. By using focus-group discussions as a qualitative method of research when analysing the result, five themes with corresponding categories emerged, describing a development of understanding and learning about capacities. Themes describing how the participants could apply strategies to overcome shortcomings in daily occupations and the therapeutic role of the occupational therapist were identified as well. The result shows that a computer training program such as RehaCom can be used as an educational tool, for example, to guide a person who is trying to adopt compensatory strategies to avoid overload by taking pauses. It was found that anything the participants learned was also applicable to occupational performance in daily life.