槲皮素在苯并芘致小鼠DNA损伤中的作用

目的　研究槲皮素在苯并芘致小鼠DNA损伤中的作用。方法　小鼠一次性腹腔注射苯并芘 (B〔a〕P) 10 0mg/kg后 ,分别以 0 5 ,1 0 ,2 0g/ (kg·d)剂量的槲皮素连续灌胃 90d。取小鼠尾部静脉血进行单细胞凝胶电泳实验 ,通过荧光显像的方法观察并测量血细胞的拖尾长度。结果　阴性对照组小鼠的细胞无拖尾现象 ,高、中、低剂量槲皮素组和苯并芘阳性对照组的细胞均有拖尾现象。对彗尾进行统计学分析 ,与对照组相比 ,各剂量组均有显著性差异 (P <0 0 5 )。染毒组用不同剂量的槲皮素处理后 ,DNA的损伤程度显著减少。结论　槲皮素对苯并芘引起的小鼠DNA损伤有显著的保护作用     

阿霉素对雄性小鼠生殖毒性影响的研究

[目的]探讨阿霉素对雄性小鼠生殖细胞毒性的影响。[方法]将60只雄性小鼠随机等分为3组,A组腹腔注射阿霉素溶液(3mg·kg-1·d-1),B组腹腔注射阿霉素溶液(5mg·kg-1·d-1),C组为对照组,腹腔注射生理盐水,连续注射5d,一半小鼠d6取双侧睾丸行微核实验,另一半小鼠染毒结束后28d后取附睾,计数小鼠精子畸形率,评价阿霉素对小鼠的生殖毒性作用。[结果]阿霉素实验组精子畸形率[(A组(4.34±0.31)%,B组(6.70±0.55)%]与对照组(2.82±0.23)%相比差异有统计学意义(P﹤0.01);实验组生殖细胞微核率[A组(5.20±1.21)‰,B组(6.70±0.55)‰]与对照组[(2.40±0.71)‰]相比差异有统计学意义(P﹤0.01),呈剂量依赖性。[结论]小鼠腹腔注射阿霉素对雄性小鼠生殖细胞有损害作用。     

环磷酰胺染毒小鼠精子形态及精细胞微核变化

目的探讨环磷酰胺对小鼠生殖毒性的影响。方法小鼠腹腔注射环磷酰胺溶液,连续5d染毒,染毒后28d取双侧睾丸和附睾,计数小鼠精子畸形率和生殖细胞微核发生情况,评价环磷酰胺对小鼠的生殖毒性作用。结果腹腔注射环磷酰胺实验组精子畸形率与对照组相比差异有显著性(P<0.01);实验组生殖细胞微核率与对照组相比差异有显著性(P<0.05)。结论小鼠腹腔注射环磷酰胺对雄性小鼠生殖细胞和精子有损害作用。     

褪黑素对大鼠脊髓损伤早期MDA、SOD水平的影响

目的:通过观察褪黑素(melatonin,MT)对脊髓损伤早期(12h)大鼠体内超氧化物歧化酶(superoxide dismutase,SOD)、丙二醛(malondialdehyde,MDA)水平的影响,探讨褪黑素治疗脊髓损伤的机制。方法:36只成年SD大鼠随机分为3组:脊髓损伤组(A组)、褪黑素治疗组(B组)、假手术组(Sham组),每组12只。A、B两组以改良的Allen's weight drop(WD)法(打击量50gcf)建立脊髓T12水平损伤模型,Sham组仅行椎板切除不损伤脊髓。B组于术后10 min按体重腹腔注射100mg/kg的MT,A组则按体重腹腔注射等体积的无水乙醇(MT的溶剂)。结果:术后12h,血清中MDA含量比较,A、B两组大鼠于术后均出现了严重的下肢神经功能障碍,两组的BBB运动功能评分差异无统计学意义(P0.05)。结论:MT可抑制大鼠脊髓损伤早期体内脂质过氧化反应,其机制可能为它可保护大鼠体内SOD的活性,间接地抑制脂质过氧化反应;按体重腹腔注射100mg/kg的MT,并不能显著改善大鼠脊髓损伤早期后肢的运动功能障碍。     

FK506对脊髓背横断导致脊髓损伤的改善作用及可能机制探讨

目的探讨他克莫司(FK506)对脊髓背横断导致脊髓损伤的改善作用及可能机制。方法采用小鼠下胸段脊髓背横断机械损伤模型诱导脊髓损伤,并根据处理情况分为4组:假手术组、损伤模型组、假手术+FK506组和损伤模型+FK506组,其中假手术+FK506组和损伤模型+FK506组于术后给予2 mg/kg FK506腹腔注射,1次/d,连续2周,其余两组均给予等体积的生理盐水。采用BMS开场运动测试和横梁跑动实验分别检测后肢运动功能的恢复程度和运动协调能力;辐射热痛觉阈值检测检测对伤害刺激的反应速率;甲苯胺蓝染色检测脊髓的损伤面积;特异性荧光探针DHE染色观察病变局部脊髓的超氧阴离子水平;ELISA法检测病变局部脊髓的MDA、TNF-α水平和SOD活性;Western blot法检测病变局部脊髓的Lingo-1、GAP-43、Bcl-2及Bax水平。结果相比于假手术组,损伤模型组的BMS主要评分、次级评分、横梁跑动得分、病变局部脊髓的SOD活性、GAP-43和Bcl-2水平均降低,后爪回缩时间、病变局部脊髓的损伤面积、超氧阴离子、MDA和TNF-α水平及Lingo-1和Bax水平均升高,差异有统计学意义(P0.05);而FK506处理可改善脊髓背横断导致病变局部脊髓的以上异常症状,但仍与假手术组有差异;FK506处理对假手术组的以上指标均无影响。结论 FK506可改善脊髓背横断导致病变局部脊髓的损伤,降低炎症指标水平及氧化应激,可能与其抑制Lingo-1表达及降低凋亡水平有关。     

神经营养素-3对大鼠脊髓损伤后神经丝蛋白及胶质纤维酸性蛋白表达的影响及意义

目的研究神经营养素-3(NT-3)对大鼠脊髓损伤后神经元中丝蛋白(NF200)及星形胶质细胞胶质纤维酸性蛋白(GFAP)表达的影响,探讨NT-3在脊髓损伤修复中的作用。方法SD大鼠24只,分为假手术组、损伤对照组和NT-3组,每组8只,于损伤前和损伤后1 d、7 d、14 d、21 d和28 d用BBB评分评定大鼠运动功能,然后处死动物用免疫组化染色及图像分析方法观察NF200及星形胶质细胞GFAP的表达。结果BBB评分,14 d、21 d和28 d点NT-3组明显高于损伤对照组;脊髓损伤后NF200及GFAP表达增加,且NT-3干预后表达更为明显,与其他2组相比差异有统计学意义(P<0.05)。结论NT-3促进星形胶质细胞增生及神经元功能的活跃,可能是促进神经纤维再生的一个重要因素。     

蒽贝素对脂多糖诱导小鼠心脏炎症损伤的影响

目的研究蒽贝素对脂多糖(LPS)诱导小鼠心肌损伤的影响及其作用机制。方法从80只C57BL/6J(B6)雄性小鼠中随机抽取16只作为正常对照组,腹腔注射生理盐水10 mg/kg;其余64只腹腔注射10 mg/kg LPS,等分为脓毒症阳性对照组和低、中、高浓度治疗组4组,每组16只,治疗组小鼠再分别腹腔注射5、10、20 mg/kg蒽贝素。采用双位点酶免法测定血清中心肌肌钙蛋白I(c Tn I)水平,免疫组化法检测心肌PPAR-γ和TNF-α水平,蛋白免疫印迹试验(WB)检测NF-κB水平。结果正常对照组、中浓度治疗组、高浓度治疗组小鼠血清c Tn I水平、细胞核内NF-κB蛋白灰度比值和心肌细胞TNF-α黄染率均低于脓毒症阳性对照组(均P0.05);脓毒症阳性对照组与正常对照组小鼠心肌细胞PPAR-γ黄染率差异无统计学意义(P0.05),各治疗组小鼠心肌细胞PPAR-γ黄染率均升高(P0.01)。结论蒽贝素可剂量依赖性地改善LPS诱导的小鼠心肌损伤,其机制可能为上调PPAR-γ表达、抑制NF-κB活化和减少TNF-α合成。     

染料木素对小鼠急性肝损伤的保护作用

目的 观察染料木素(genistein,GEN)对小鼠急性肝损伤的保护作用.方法 采用健康昆明种小鼠,以灌胃的方法连续7 d给予不同浓度GEN或联苯双酯,末次给药1 h后,腹腔注射0.1%CCl4建立小鼠急性肝损伤模型,染毒后16 h取肝脏,分别制备10%、1%肝匀浆,测定肝匀浆中丙二醛(MDA)含量、天冬氨酸转氨酶(AST)与丙氨酸转氨酶(ALT)活力,并计算AST/ALT比值和观察肝损伤病理学变化.结果 GEN剂量组的MDA含量分别为(730.95±78.28)、(650.00±87.26)和(479.17±52.79)nmol/g,均明显低于模型组,差异有统计学意义(P＜0.05或P＜0.01),3个GEN剂量组的AST、ALT活力与AST/ALT比值均明显高于模型组,差异有统计学意义(P＜0.05或P＜0.01),GEN剂量组肝脏病理性损伤减轻.结论 GEN对小鼠急性肝损伤具有一定的保护作用.     

钙蛋白酶抑制剂对丙烯酰胺中毒大鼠神经毒性的拮抗作用

目的探讨钙蛋白酶抑制剂(calpeptin,CP)对丙烯酰胺(acrylamide,ACR)中毒大鼠神经毒性的拮抗作用。方法将30只健康成年雌性Wistar大鼠随机分为对照组、ACR中毒组、CP干预组3组,每组10只。ACR中毒组腹腔注射ACR30 mg/kg,3次/周,共4周;对照组腹腔注射等体积生理盐水;CP干预组腹腔注射ACR后1 h再腹腔注射CP 200μg/kg,3次/周,共4周。测定体重、步态评分、后肢撑力和神经组织细胞内钙蛋白酶(calpain)活力。结果与对照组相比,ACR中毒组大鼠体重增加缓慢(P0.05);与ACR中毒组相比,CP干预组大鼠体重在第2周显著升高(P0.05)。ACR中毒组和CP干预组步态评分和后肢撑力明显高于对照组(P0.01),CP干预组明显高于ACR组(P0.05)。ACR中毒组和CP干预组脊髓、坐骨神经细胞中calpain活力均明显高于对照组(CP干预组坐骨神经除外);CP干预组脊髓、坐骨神经细胞中calpain活力明显低于ACR组(P0.05)。结论 CP可通过抑制钙蛋白酶的活力拮抗ACR诱导的神经毒作用。     

槲皮素对矽肺大鼠转化生长因子β1 信号转导通路的调节作用

［目的］ 观察槲皮素（Quercetin）对矽肺大鼠转化生长因子β1（transforming growth factor,TGF-β1）信号转导通路的调节作用。 ［方法］ 将75 只SPF 级Wistar 雄性大鼠随机分为对照组、模型组、槲皮素治疗组,每组25 只。模型组与槲皮素治疗组大鼠采用非暴露法气管内一次性注入二氧化硅（SiO2）悬液（250 mg/kg）复制动物矽肺模型。槲皮素治疗组自注射SiO2 后每天腹腔注射槲皮素50 mg/kg/1.0 mL生理盐水,对照组以同样方法注入等量生理盐水,共连续处理14 d。动物分别在注射SiO2 后第3、7、14、21、28 天处死。应用羟脯氨酸试剂盒检测肺组织中总胶原蛋白含量,免疫组织化学 法检测肺组织TGF-β1 表达,蛋白免疫印迹（Western blot）法检测TGF-β1 直接底物p-Smad3/7 蛋白表达情况。 ［结果］模型组肺组织中总胶原蛋白含量与同期对照组比较明显增加,分别是对照组的6.28、13.11、11.59 倍（P 〈 0.01）。槲皮素治疗组与模型组相比,总胶原蛋白含量明显下降,分别是同期模型组的43.05%、38.92%、37.40%（P 〈 0.01）。槲皮素治疗组的TGF-β1 阳性表达低于模型组,而明显高于对照组,各时间点与对照组比较,差异有统计学意义（P 〈 0.01,P 〈 0.05）。模型组大鼠肺组织中p-Smad3 表达量高于对照组及槲皮素治疗组,各时间点比较,差异均有统计学意义（P 〈 0.01）。槲皮素治疗组各时间点与相应模型组相比,p-Smad3 表达减少,但仍高于相应对照组（P 〈 0.01）。模型组大鼠肺组织中p-Smad7表达量低于对照组及槲皮素治疗组,各时间点比较,差异均有统计学意义（P 〈 0.01）。槲皮素治疗组各时间点与对照组、模型组相比,p-Smad7 表达量升高（P 〈 0.01）。 ［结论］ 槲皮素通过减少Smad3 蛋白,增加Smad7 蛋白表达,抑制矽肺过程中胶原蛋白的产生。     

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.