鲟鱼金属硫蛋白排铅作用及对锌含量影响的研究

目的:探讨鲟鱼金属硫蛋白对铅中毒小鼠的排铅作用及其对锌含量的影响。方法:将昆明种小鼠20只随机分成正常组、铅模型组、阳性药物组(依地酸二钠钙)和金属硫蛋白组(以鲟鱼金属硫蛋白灌胃)。除正常组外,其它三组连续30 d自由饮用1.65%的醋酸铅水溶液。30 d后,测量脾脏系数,血液、股骨、睾丸中的铅和锌含量。结果:MT组小鼠血铅和股骨铅水平均明显低于铅模型组小鼠(P<0.05);MT组小鼠血锌水平均显著高于正常组和铅模型组(P<0.05),股骨锌含量低于正常组(P<0.05)。但未见MT对睾丸的铅、锌水平及氧化损伤保护有明显的影响。结论:鲟鱼MT具有促进排铅和拮抗铅中毒引起的锌含量下降的作用。     

松花粉对小鼠急性酒精性肝损伤的保护作用研究

目的:研究松花粉对小鼠急性酒精性肝损伤的保护作用。方法:通过预先给予各组小鼠松花粉,剂量分别为500、1000mg/kg,30d后各剂量组及模型对照组小鼠经口一次给予乙醇4800mg/kg,建立急性肝损伤模型,观察松花粉对急性肝损伤小鼠肝脏脂质过氧化反应、肝细胞脂肪变性等的影响。结果:12h后各剂量组小鼠肝组织MDA含量与乙醇模型组相比均降低,高剂量组具有显著差异(P<0.05);低、高剂量组肝组织GSH含量均高于乙醇模型对照组,分别具有显著和极显著差异(P<0.05,P<0.01)。肝组织苏丹Ⅲ染色显示,各剂量组肝细胞内脂滴比乙醇模型对照组明显减少。结论:实验结果表明松花粉能对抗酒精中毒引起的肝脏脂质过氧化损伤,具有有效的保肝作用。     

金属硫蛋白排铅和肝脏保护作用的实验研究

目的探讨金属硫蛋白(metallothionein,MT)对染铅小鼠的排铅作用以及对肝脏的保护作用。方法小鼠连续30d饮用0.55g/L醋酸铅水溶液制作铅中毒模型组,以MT灌胃的小鼠作为治疗组,并以依地酸二钠钙作为阳性药物对照组。结果MT组小鼠股骨铅含量为(8.50±4.53)μg/g,明显低于铅模型组(P<0.05);MT组小鼠血清中丙氨酸氨基转移酶(ALT)为(27.44±3.43)U/L,明显低于铅模型组(P<0.05),但肝脏中ALT为(232.83±18.08)U/L,明显高于铅模型组(P<0.05)。MT组、正常组和铅模型组小鼠血清和肝脏中的天冬氨酸氨基转移酶(AST)比较,差异无统计学意义(P>0.05);染铅小鼠肝细胞膜Na+-K+ATP酶和Ca2+-Mg2+ATP酶活力没有明显变化。结论MT具有明显的促排铅作用;但对肝脏的保护作用不明显。     

金属硫蛋白治疗硫酸镍致肾脏损伤的实验研究

目的 探讨金属硫蛋白（MT）对硫酸镍致小鼠肾脏损伤的治疗效果及作用机制. 方法 60只清洁级昆明（KM）种小鼠,雌雄各半,随机分为5组：对照组,硫酸镍（Ni＋2）染毒组,低、中、高剂量MT治疗组.对照组灌胃生理盐水,镍染毒组灌胃2.5 mg/kg·bw硫酸镍溶液;MT治疗组在给予Ni＋2染毒后再分别按5.0、10.0、20.0 mg/kg· bw剂量灌胃MT.各组灌胃时间均为15 d,每日一次;灌胃体积均为0.1 ml/10 g·bw.实验结束麻醉处死动物采血,取双肾脏作病理学检测;全自动生化分析仪检测血清BUN和CRE含量;试剂盒检测肾组织SOD活性和MDA含量. 结果 与对照组比较,镍染毒小鼠血清BUN和CRE增高、肾组织SOD活力下降、MDA含量增高（P＜0.05）.MT治疗后与镍染毒组比较小鼠血清BUN和CRE降低,SOD活力升高、MDA含量下降（P＜0.05）;MT治疗后肾病理损伤明显减轻,细胞管形消失,核坏死、出血等病变明显改善,其中以高剂量MT治疗肾损伤效果更佳. 结论 金属硫蛋白对镍致小鼠肾损伤有治疗作用,其机制与抗氧化损伤有关.     

复肝肽对四氯化碳致小鼠肝损伤的保护作用

目的 探讨复肝肽对四氯化碳(CCl4)引起的小鼠化学性肝损伤的保护作用.方法 将ICR小鼠随机分为5组,1个正常对照组、1个CCl4模型对照组和高、中、低剂量复肝肽 CCl4组(复肝肽的剂量分别为2.5、5.0、10.0 ml/kg),每组10只.采用CCl4致小鼠化学性肝损伤模型,观察各组小鼠肝损伤情况.结果 与CCl4模型对照组比较,中剂量复肝肽 CCl4组小鼠血清丙氨酸氨基转移酶(ALT)活力明显降低,差异有统计学意义(P＜0.01);肝脏组织细胞变性、坏死程度明显减轻,差异有统计学意义(P＜0.05).与CCl4模型对照组比较,高剂量复肝肽 CCl4组小鼠肝脏组织细胞变性程度减轻,差异有统计学意义(P＜0.05).结论 复肝肽对四氯化碳急性染毒致小鼠肝损伤的愈复有促进作用.     

金属硫蛋白对急性化学性肝损伤的保护作用研究

[目的]研究含金属硫蛋白(metallothionein,MT)蛋奶粉对CCl4致大鼠急性肝损伤的保护作用。[方法]70只Wistar大鼠随机分为正常对照组10只、模型组20只、低和高剂量MT蛋奶粉治疗组各20只。低和高剂量MT蛋奶粉治疗组大鼠以含MT蛋奶粉灌胃1周,然后对除正常对照组以外的大鼠复制CCl4肝损伤模型,于造模当日,正常对照组和模型组大鼠用蒸馏水,治疗组用含MT蛋奶粉连续灌胃2周后,断头处死大鼠,观察各组大鼠血清酶类含量的变化和肝脏过氧化物质和抗氧化酶类(SOD、CAT)和GSH含量的变化。[结果]与正常对照组相比,模型组大鼠血清中ALT、AST、GGT和ALP含量显著升高(P<0.01),而含MT蛋奶粉治疗组大鼠血清中ALT、AST、GGT和ALP含量均显著低于模型组,尤其以高剂量组为显著(P<0.01)。含MT蛋奶粉组大鼠肝脏MDA含量显著低于模型组(P<0.01),抗氧化酶类SOD活性和抗氧化物质GSH含量显著高于模型组(P<0.05或P<0.01),对CAT活性并无显著性影响。[结论]含MT蛋奶粉对CCl4造成的大鼠急性肝损伤具有一定程度的保护作用。     

ZnCl2对二甲基甲酰胺所致小鼠急性肝毒性的保护作用研究

目的 研究ZnCl2对二甲基甲酰胺(N,N-dimethylformamide,DMF)致小鼠急性肝损伤的保护作用,为保护DMF接触人群提供指导.方法 将80只动物随机分为8组:正常对照组、DMF组、ZnCl2-10 DMF组、ZnCl2-20 DMF组、ZnCl2-40 DMF组、ZnCl2-10组、ZnCl2-20组和ZnCl2-40组.所有ZnCl2给药组每天皮下注射一定剂量的ZnCl2溶液.ZnCl2-10、ZnCl2-20和ZnCl2-40组在DMF染毒之前,其余组在DMF染毒后48 h处死小鼠,测定其血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)和乳酸脱氢酶(LDH)的活力;制备肝匀浆,测定ZnCl2-10、ZnCl2-20和ZnCl2-40组小鼠肝金属硫蛋白(MT)含量;留取肝脏组织,常规石蜡包埋切片,HE染色,光镜观察肝脏组织病理变化.结果 与正常组比较,DMF组小鼠血清中ALT、AST和LDH活力明显升高,肝脏组织出现明显的肝细胞变性坏死;ZnCl2 DMF组的小鼠血清中ALT、AST和LDH活力与DMF组相比明显降低,肝脏组织病理损伤明显减轻.单独给予ZnCl2组小鼠MT含量升高.结论 ZnCl2对DMF引起的小鼠急性肝损伤具有明显的保护作用.     

金属硫蛋白对镍铬联合染毒小鼠肝脏损伤的拮抗作用

目的研究硫酸镍+重铬酸钾联合染毒对小鼠肝脏损伤的影响及金属硫蛋白(MT)的拮抗作用。方法将50只健康SPF级昆明小鼠按体重随机分为5组,分别为溶剂对照组(生理盐水)、镍铬(1.0 mg/kg硫酸镍+0.5 mg/kg重铬酸钾)联合染毒组和低、中、高剂量MT保护(1.0 mg/kg硫酸镍+0.5 mg/kg重铬酸+5.0、10.0、20.0 mg/kg MT)组,每组10只,雌雄各半。采取灌胃方式进行染毒,染毒容量为10 ml/kg,每天1次,连续染毒21 d。检测小鼠丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、γ-谷氨酰转肽酶(GGT)活力及肝组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)、谷胱甘肽(GSH)含量。结果与溶剂对照组比较,镍铬联合染毒组小鼠血清AST、ALT、GGT的活力均增高,差异均有统计学意义(P0.05)。各剂量MT保护组小鼠血清AST、ALT、GGT的活力均低于镍铬联合染毒组,差异均有统计学意义(P0.05);且随着MT染毒剂量的升高,MT保护组小鼠血清AST、ALT、GGT的活性均呈下降趋势。与溶剂对照组比较,镍铬联合染毒组小鼠肝组织SOD、GSH-Px活力和GSH含量均下降,而MDA含量升高,差异均有统计学意义(P0.05)。与镍铬联合染毒组比较,各剂量MT保护组小鼠肝组织SOD、GSH-Px活力和GSH含量均升高,而MDA含量均降低,差异均有统计学意义(P0.05),且随着MT染毒剂量的升高,MT保护组小鼠肝组织SOD、GSH-Px活力和GSH含量均呈上升趋势,而MDA含量呈下降趋势。结论 MT对镍铬联合染毒所致小鼠肝脏损伤有较好的拮抗作用,其作用机制可能与MT抗氧化作用有关。     

蝙蝠蛾拟青霉复合胶囊对四氯化碳与酒精所致小鼠急性肝损伤保护作用

目的探讨蝙蝠蛾拟青霉复合胶囊对四氯化碳与酒精所致小鼠急性肝损伤的保护作用。方法分别采用四氯化碳和酒精灌胃诱导小鼠急性肝损伤模型,测定四氯化碳急性肝损伤模型小鼠血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)的含量及酒精急性肝损伤模型小鼠肝组织中丙二醛(MDA)、甘油三酯(TG)、还原型谷胱甘肽(GSH)的含量并观察2组肝组织切片病理形态学变化。结果蝙蝠蛾拟青霉复合胶囊675、2 025 mg/kg BW剂量组四氯化碳急性肝损伤小鼠血清的ALT、AST含量均低于模型对照组,差异具有统计学意义(P 0.05)。急性酒精性肝损伤模型中,675、2 025 mg/kg BW剂量组的MDA含量和3个剂量组的TG含量明显低于模型对照组,675、2 025 mg/kg BW剂量组的GSH含量明显高于模型对照组,差异均具有显著性(P 0.05)。小鼠肝组织形态学结果表明,四氯化碳肝损伤模型肝组织中、高剂量组的肝脏细胞坏死程度与模型对照组比较积分显著下降,差异具有显著性(P 0.05),各剂量组气球样变积分和高剂量组水样变程度积分也较模型组有显著性降低(P 0.01);蝙蝠蛾拟青霉复合胶囊能显著改善急性酒精性肝损伤小鼠肝细胞脂肪变性程度,差异具有显著性(P 0.05)。结论蝙蝠蛾拟青霉复合胶囊对小鼠急性肝损伤具有较好的辅助保护功能。     

花锚中3种(口山)酮苷对小鼠肝损伤保护作用

目的 研究花锚提取物中3种(口山)酮苷对肝脏保护作用.方法 用CCl4灌胃小鼠,建立急性肝损伤动物模型,观察其肝脏组织形态,测定肝脏系数,血清中谷丙转氨酶、谷草转氨酶活性和肝糖元含量,研究3种(口山)酮苷对小鼠肝损伤的保护作用.结果 模型组中小鼠的血清谷丙转氨酶(ALT)、谷草转氨酶(AST)活性、肝脏系数、肝糖元A值分别为(1045.61±47.82),(1323.52±230.22)U/L,(0.062±0.0041),(0.062±0.013);与模型组比较,花锚中3种(口山)酮苷高剂量组(10 mg/ml)对小鼠实验性肝损伤均有明显的修复作用,能降低CCl4所致肝损伤小鼠的肝脏系数、血清ALT、AST活性,并提高肝糖元含量(P<0.01);化合物A、B、C中剂量组(5 mg/ml)的肝糖元A值分别为(0.072±0.011),(0.077±0.015),(0.078±0.012),与模型组相比均明显升高(P<0.05),其余各项指标与模型组比较,差异均有统计学意义(P<0.01);与模型组比较,化合物B低剂量组(1 mg/ml)可有效降低小鼠的肝脏系数及血清AST活性(P<0.05),化合物C低剂量组可明显降低小鼠血清AST活性(P<0.01),对ALT活性的升高也有较好的抑制作用(P<0.05),而其他给药组与模型组比较,差异均无统计学意义.结论 花锚中3种(口山)酮同苷均有较好的保肝作用,为花锚保护肝脏的有效成分、且具有一定的量效关系.     

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.     

Worker education in the primary prevention of occupational dermatoses

This paper reports the evaluation of a skin care education programmeconducted on a fine chemicals manufacturing site where over1,000 employees are located. Approximately 60% are involvedin chemical manufacture. Over a 12 month period production staffreceived training in prevention of occupational dermatoses linkedto a site-wide poster initiative. The incidence of new casesof occupational dermatoses fell from 0.055 (70 cases in 1,277employees) to 0.021 (27 cases in 1,277 employees) before andafter the intervention respectively (p<0.0001). After otherfactors such as chemicals handled, observer bias and changesin reporting related to socioeconomic climate were taken intoaccount it is concluded that this study demonstrates the importanceof worker education as a tool for primary prevention of disease.Training materials such as video and poster presentations maybe effectively used in the chemical manufacturing industry asan adjunct to prevention and control of exposure to substanceshazardous to the skin. Such methods may also be used in otherindustries where there are significant risks of dermatoses.     

Regional Variation in Travel-related Illness acquired in Africa,March 1997–May 2011

To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.     

The design of hazard risk assessment matrices for ranking occupational health risks and their application in mining and minerals processing

Two hazard risk assessment matrices for the ranking of occupational health risks are described. The qualitative matrix uses qualitative measures of probability and consequence to determine risk assessment codes for hazard-disease combinations. A walk-through survey of an underground metalliferous mine and concentrator is used to demonstrate how the qualitative matrix can be applied to determine priorities for the control of occupational health hazards. The semi-quantitative matrix uses attributable risk as a quantitative measure of probability and uses qualitative measures of consequence. A practical application of this matrix is the determination of occupational health priorities using existing epidemiological studies. Calculated attributable risks from epidemiological studies of hazard-disease combinations in mining and minerals processing are used as examples. These historic response data do not reflect the risks associated with current exposures. A method using current exposure data, known exposure-response relationships and the semi-quantitative matrix is proposed for more accurate and current risk rankings.     

Psychopathological features of a patient population of targets of workplace bullying

BACKGROUND: A strong association between workplace bullying and subsequent anxiety and depression, indicated by empirical research, suggests that bullying is an aetiological factor for mental health problems. AIMS: To evaluate levels of stress and anxiety-depression disorder developed by targets of workplace bullying together with outcome at 12 months and to characterize this population in terms of psychopathology and sociodemographic features. METHODS: Forty-eight patients (36 women and 12 men) meeting Leymann Inventory of Psychological Terror criteria for bullying were included in a prospective study. Evaluations were performed at first consultation and at 12 months using a standard clinical interview, a visual analogue scale of stress, the Hospital Anxiety and Depression (HAD) scale, the Beech scale of stress in the workplace and a projective test (Picture-Frustration Study). RESULTS: At first consultation, 81% of patients showed high levels of perceived stress at work and 83 and 52% presented with anxiety or depression, respectively. At 12 months, only 19% of working patients expressed a feeling of stress at work. There was a significant change in symptoms of anxiety while there was no change in symptoms of depression. Stress at work and depression influenced significatively capacity to go back to work. At 12-month assessments, workers showed a significantly better score on the HAD scale than non-workers. Over half the targets presented a neuroticism-related predominant personality trait. CONCLUSION: Workplace bullying can have severe mental health repercussions, triggering serious and persistent underlying disorders.     

The rise and fall in incidence of malignant mesothelioma from a British Naval Dockyard, 1979-1999

BACKGROUND: The incidence of malignant mesothelioma in Britain is predicted to rise over the next 15-25 years because of past failure to protect the workforce against inhalation of asbestos. In British Naval dockyards, alternative insulation materials and respiratory protection were introduced from the mid-1960s. Aims This study was carried out to investigate the effects of these control measures on mesothelioma deaths in dockyard workers. METHODS: Cases of mesothelioma of the pleura and peritoneum between 1979 and 1999 in workers from the Devonport Naval Dockyard, south-west England, were sought from coroners' and medico-legal records. RESULTS: Three hundred and one cases were identified, 7% peritoneal. The peak incidence occurred in 1991 with 25 cases per annum (quadratic model fit R(2) = 74.2%, P < 0.001) and we predict that by 2003 the incidence will fall to fewer than five cases per annum. The mean time between first exposure and presentation was 48.5 years [95% confidence interval (CI) = 47.3-49.8], but this was significantly shorter in the more heavily exposed trades, when compared with the less heavily exposed (42 years, 95% CI = 39.0-45.0, versus 49.5 years, 95% CI = 48.2-50.9). Those with higher exposure were also at significantly greater risk of peritoneal disease (P < 0.023, Fisher's exact test). CONCLUSION: The reduction in incidence of mesothelioma is greater than can be accounted for by reduction in numbers of dockyard workers over the last 50 years. Changes in insulation materials and improved industrial hygiene measures introduced into the Devonport Dockyard from the mid-1960s have resulted in an earlier decline in the incidence of malignant mesothelioma than that predicted for the British workforce as a whole.     

Organophosphate toxicity and occupational exposure

The ubiquitous organophosphates present a continuing health hazard in agriculture, public health eradication programmes and as chemical warfare agents. Despite significant progress in understanding the potential mechanisms of toxicity far beyond the commonly accepted mechanism of cholinesterase inhibition in intentional exposures, the precise health effects following occupational exposures are yet to be completely defined. A much greater understanding exists of the clinical features of organophosphate poisoning. These are characterized by a triphasic response involving an initial acute cholinergic phase, an intermediate syndrome (both associated with high mortality) and a disabling but non-lethal delayed polyneuropathy. The delayed polyneuropathy may occur in the absence of the cholinergic or intermediate phases. However, progress is still required in order to improve the quantification and assessment of occupational exposures and the implementation of appropriate preventive measures. Finally, evidence-based guidelines for appropriate or optimal therapeutic interventions following poisoning are required urgently and collaborative work with colleagues in developing countries, where the occurrence of organophosphate exposures is more frequent, may provide the answers.     

Miliaria rubra of the lower limbs in underground miners

This report documents a case series of miliaria rubra of the lower limbs in miners at a deep underground metalliferous mine in tropical arid Australia. During the summer months of February and March 1999, all cases of miliaria rubra of the lower limbs in underground miners seen at the mine's medical centre were clinically examined and administered a questionnaire. Twenty-five patients were seen, an incidence of 56.4 cases per million man-hours. Miliaria rubra was most often located between the ankle and knee (88% of cases). Twenty-four percent had concurrent folliculitis and 20% had concurrent tinea. Thirty-two percent had a personal history of asthma. Walking through ground-water and splashing of the legs was common. Three to 4 weeks of sedentary duties in air conditioning was generally required to achieve resolution of miliaria rubra. The incidence of miliaria rubra of the lower limbs is 38% of the incidence of heat exhaustion at the same mine. The length of disablement is greater, however. Atopics may be at increased risk of miliaria rubra. Control measures are discussed.     

Planning research

The starting point for any research project should be a question.Once this has been defined and the relevant scientific literaturereviewed, a protocol should be drawn up. This will be used notonly as a guide to the conduct of the study and in the preparationof the final report, but also in seeking any financial supportand approvals that are required for the investigation. A protocolis normally arranged in sections covering the background tothe study, the question(s) that it will address, the methodsthat will be used for the collection and analysis of data, thestatistical power of the investigation (where relevant), anyethical considerations, and the financial input that will beneeded. A pilot study is often helpful where aspects of thestudy method are untried or of uncertainvalidity.     

Stress in the Norwegian police service

BACKGROUND: High levels of stress have been attributed to the conditions of police work, but there is little empirical evidence for this. AIMS: To develop a new instrument to measure job stress in the police; to assess the most severe and frequent police stressors; to compare levels of stress according to the demographic and organizational factors; and to study stress in relation to personality traits, work locus of control and coping strategies. METHODS: A comprehensive nationwide questionnaire survey of 3272 Norwegian police at all hierarchical levels, including the Norwegian Police Stress Survey (NPSS), the Job Stress Survey, the Basic Character Inventory, the Work Locus of Control Scale, and the Coping Strategies Scale. RESULTS: Work injuries were appraised as the most stressful but least frequent stressor and job pressure was reported the least severe but most frequent stressor. Females experienced job stressors less frequently, but appraised them as more severe than men did. Older police officers reported more job pressure severity and fewer work injuries. The police in districts where peer support was planned but not implemented, and who worked in districts with more than 50,000 inhabitants, perceived the lack of support more severely than others. The correlations between stress and personality traits, work locus of control, and coping were moderate. CONCLUSIONS: The NPSS captures police-specific stressors that are not adequately measured by global stress instruments. The study of stress in police work should preferably involve a nationwide use of police-specific stress instruments.