制蚜菌素对大鼠的亚慢性经口毒性

目的研究制蚜菌素对SD大鼠的亚慢性经口毒性。方法按照GB 15670-1995《农药登记毒理学实验方法》,设为0.0、2.4、9.6、38.3 mg/kg饲料4个剂量组,每组20只大鼠,雌雄各半;分别采用无明显损害作用剂量(NOAEL)和基准剂量(BMD)计算亚慢性经口毒性阈值。结果大鼠亚慢性经口毒性试验显示,高、中剂量组肝重、肝脏器系数及摄食量低于对照组,差异有统计学意义,且均存在剂量-效应关系,呈负相关。结论制蚜菌素原药亚慢性经口毒性NOAEL雌雄性大鼠分别为(0.22±0.02)、(0.18±0.01)mg/(kg.d),BMD的95%可信限下限(BMDL)雌雄性大鼠分别为0.790、0.319 mg/(kg.d)。     

除草剂特丁津亚慢性毒性阈值分析

目的　应用基准剂量法 (BMD)和无明显损害作用剂量 (NOAEL)法分析特丁津 (Terbutryn ,2 -特丁胺基 -4 -氨 -6-乙胺基 -均三氮苯 )原药亚慢性毒性阈值并进行比较。方法　特丁津亚慢性毒性试验 (90d)设对照、低、中、高剂量组 (0、167、5 0 0、15 0 0mg/kg饲料 ) ,基准剂量计算采用EPA(美国国家环保局 )的BMDS软件。结果　中、高剂量组雌雄性大鼠食物利用率低于对照组 ,肾脏体系数高于对照组 ,高剂量组雌雄性大鼠生化指标BUN高于对照组 ,差异有统计学意义。中高剂量组少数动物出现肝脏、肾脏炎症小灶 ;低剂量组雌雄性大鼠均未见明显异常。特丁津原药NOAEL值雄性大鼠为11 80mg/(kg·d) ,雌性大鼠为 12 84mg/(kg·d)。特丁津原药的BMDL(基准剂量的可信限下限值 )雌雄大鼠分别为 10 0 2、9 77mg/(kg·d) ,均小于相应的NOAEL。结论　选择的BMD值在低剂量组和中剂量组之间 ,即BMD值大于NOAEL。而BMD的可信性下限BMDL值除了雄性大鼠单指标计算的BMDL值外 ,均小于NOAEL。     

基准剂量法在咪鲜胺锰盐亚慢性毒性研究中的应用

[目的 ]应用基准剂量法分析咪鲜胺锰盐 (tetrakis[N propyl N [2 ( 2 ,4,6 trichlorophenoxy)ethyl]imiazole 1 car boxamide]manganese(Ⅱ )chloridecomplex)原药亚慢性毒性试验结果 ,估算其基准剂量。 [方法 ]SD大鼠咪鲜胺锰盐亚慢性喂饲毒性试验 ( 90d) ,设对照、低、中、高剂量组 ( 0、111、3 3 3、10 0 0mg/kg饲料 )。观察指标有 :大鼠中毒症状及死亡情况、体重及摄食量变化、血液常规和生化及病理组织学变化。基准剂量计算采用EPA的BMDS软件。 [结果 ]雄性大鼠高剂量组肝体比、肾体比、睾体比及中剂量组肾体比 ,与对照组相比 ,差异有统计学意义 ;雌性大鼠高剂量组肝体比、肾体比及中剂量组肝体比 ,与对照组相比 ,差异有统计学意义 ;中、高剂量组少数动物出现肝脏、肾脏炎症小灶 ;低剂量组雌、雄性大鼠均未见明显异常。 [结论 ]咪鲜胺锰盐原药的无明显损害剂量 (NOAEL)雌、雄均为 111mg/kg饲料 ,按每日每千克体重摄入量计算 ,雌、雄大鼠NOAEL分别为 ( 9.0 7± 0 .2 7)、( 10 .3 2± 0 .66)mg/(kg·d)。咪鲜胺锰盐原药的基准剂量的 95 %可信限下限 (BMDL)值 ,雌、雄性大鼠分别为 12 1.0 6、13 4.5 1mg/kg饲料 ,按每日每千克体重摄入量计算BMDL值雌、雄性大鼠分别为 11.83、11.0 2mg/(kg·d) ,均略     

丙炔菊酯的毒性研究

目的 了解丙炔菊酯的急性与亚慢万籁 毒辣性、刺激性、突变性和致敏性。方法 按国家标准GB15670-1995《农药登记毒理学试验方法》进行大鼠急性经口、经皮与吸入毒性试验。小鼠急性皮下、腹腔注射试验。皮肤致敏试验,Ames试验和亚慢性经口试验,结果 大鼠急性经口LD50;雌性为501mg/kg,雄性为926mg/dkg;经皮LD50;雌性为2610mg/kg,雄性大于2150mg/kg;急性吸入LC50为471.5dmg/dm^3;小鼠急性皮下注射LD50;雌性为2710mg/kg,雄性为2370mg/kg;急性腹腔注射KL50;雌、雄鼠均为316mg/kg;眼、皮肤刺激为轻度刺激性;Ames试验为阴性;皮肤致敏率为6.7%;亚慢性经口毒性试验最大无作用剂量为每天2.340mg/kg。结论 丙炔菊酯的急性经口、经皮毒性为低毒级,急性吸入毒性为中毒级;为弱致敏物,无致突变性。     

重组人乳铁蛋白急性经口毒性试验和90天喂养试验

目的评价转基因奶牛乳腺生物反应器表达的重组人乳铁蛋白食用安全性。方法参照GB 15193.1—2014《食品安全国家标准食品安全性毒理学评价程序》进行小鼠急性经口毒性试验和大鼠90天亚慢性毒性试验。结果急性经口毒性试验观察期内各小鼠均未见任何毒性效应,判断重组人乳铁蛋白的小鼠急性经口LD5020 000 mg/kg;90天喂养试验结果表明,给予动物人体推荐剂量300倍的重组人乳铁蛋白,未观察到有害作用,大鼠的无明显损害作用剂量水平(NOAEL)为10.00g/(kg·d)。结论重组人乳铁蛋白属无毒级,无亚慢性毒性,无潜在的食用安全风险。     

环丙唑醇的急性和亚慢性毒性研究

为探讨环丙唑醇对大鼠的急性和亚慢性经口毒性，在急性试验中设低（215 mg/kg）、中（464 mg/kg）、次高（1 000 mg/kg）和高（2 150 mg/kg）4个剂量染毒组；在亚慢性试验中设对照组和低、中、高剂量染毒组，雌/雄性大鼠实际染毒剂量分别为1.38/1.18、7.93/7.18、47.70/48.60 mg/kg。结果显示，大鼠环丙唑醇急性经口半数致死剂量（LD50）为316 mg/kg，亚慢性经口染毒大鼠部分血液指标和肝组织病理发生改变。环丙唑醇最大无作用剂量（NOAEL）分别为1.38/7.18 mg/kg（雌/雄），长期暴露对动物肝脏具有毒性作用。     

守宫木Sauropus androgynus毒理学安全性评价

目的 研究守宫木的急性及亚慢性、细胞、遗传及免疫毒性并对其作出安全性评价.方法 对守宫木进行小鼠急性经口、大鼠亚慢性经口、细胞、遗传及免疫毒性试验.结果 全成份鲜样匀浆、叶干粉LD50值＞21.5 g/kg,梗干粉小鼠LD50值雌性20 g/kg、雄性23.3 g/kg;大鼠亚慢性经口毒性试验中干粉无明显有害作用剂量(NOAEL)为2 000 mg/kg;较低剂量守宫木对细胞生长有抑制作用,较高剂量则出现细胞增殖现象;浓缩除菌滤液剂量相当于含鲜样6×102mg/mL时,染色体畸变急剧增加,剂量达1.2×103 mg/mL时,细胞全部死亡;守宫木提取物对BALB/C小鼠脾T、B淋巴细胞体外增殖功能以及肿瘤坏死因子(TNF)、干扰素(IFN-γ)细胞因子的分泌功能均呈抑制作用,而对腹腔巨噬细胞吞噬功能呈刺激性增强作用.结论 守宫木为低毒或无毒类物质,对大鼠无明显急性毒性、亚慢性毒性,对免疫系统有一定毒物兴奋效应.     

二硝酰胺铵的急性毒性和亚慢性毒性研究

目的 对新型含能材料二硝酰胺铵(ADN)的急性毒性、亚急性毒性和亚慢性毒性进行研究,确定ADN的急性毒性分级、毒作用性质及靶器官.方法 根据《化学品毒性鉴定技术规范》,采用大鼠和小鼠急性经口毒性试验、亚急性经口(28d)毒性试验和亚慢性经口(90d)毒性试验.结果 (1)急性经口毒性试验结果表明,ADN对小鼠的经口半数致死剂量LD50为568.9 mg/kg,大鼠为616.6 mg/kg,急性毒性分级属低毒级化学物.(2)亚急性经口(28d)毒性试验结果表明,雌、雄鼠123 mg/kg剂量组体重增长明显低于对照组;61.6、123 mg/kg剂量组血清中总胆红素、天冬氨酸氨基转移酶活力明显高于对照组,肝/体比值明显低于对照组.(3)亚慢性经口(90d)毒性试验结果表明,从染毒第5周开始,123 mg/kg剂量组雌性大鼠体重增长幅度明显降低,与对照组相比,差异有统计学意义(P＜0.05);61.6、123mg/kg剂量组血清中总胆红素、天冬氨酸氨基转移酶活力高于对照组,肝/体比值明显低于对照组,肝脏病变检出例数明显高于对照组,差异均有统计学意义(P＜0.05).结论 ADN急性毒性分级属低毒级,其无可见有害作用水平(NOAEL)为30.8 mg/kg,毒作用的靶器官主要为肝脏.     

杀扑磷的毒性研究

目的　研究杀扑磷原药的急性和亚慢性毒性及致突变性 ,求出最大无作用剂量。方法　按照GB 15 670 -1995《农药登记毒理学试验方法》和GB 15 193 -94进行试验。结果　雌性大鼠LD50 为 3 8 3mg/kg ,雄性大鼠为 3 1 6mg/kg。小鼠骨髓多染红细胞微核试验和小鼠精子畸变试验均为阴性。大鼠亚慢性经口毒性试验显示 ,11 67mg/kg和 3 5 0 0mg/kg饲料组全血胆碱酯酶活力抑制明显 ,3 5 0 0mg/kg饲料组 ,雌性大鼠总摄食量明显减少。结论　杀扑磷的最大无作用剂量为 :雌性大鼠(1 2 6± 0 0 8)mg/ (kg·d) ,雄性大鼠 (0 40± 0 0 4)mg/ (kg·d)。     

溴氰菊酯毒性和致突变性的研究

目的　了解溴氰菊酯的毒性、刺激性、蓄积毒性、致敏性和致突变性。方法　按标准方法分别作大小鼠急性经口毒性 ;大鼠经皮、吸入毒性 ;皮肤、眼刺激性 ;大鼠蓄积毒性和亚慢性经口毒性试验 ;豚鼠致敏试验 ;致突变试验包括Ames、小鼠骨髓微核和睾丸精母细胞染色体畸变试验。结果　大小鼠急性LD50 分别为 2 78mg/kg和 5 6 2mg/kg ;大鼠经皮LD50 >2 0 0 0mg/kg ;急性吸入LC50 >3 0 0 0mg/m3 ;无皮肤刺激性 ,轻度眼刺激性 ;蓄积系数 2 3 ;致敏率为 0 ;Ames试验结果阴性 ;微核和染色体在高剂量组 ( 11 2 4mg/kg)与阴性对照组相比有高度显著性差异 (P <0 0 1) ;大鼠 90天亚慢性经口的最大无作用剂量为 2 82 5mg/kg。结论　溴氰菊酯有明显的蓄积作用 ,为弱致敏物 ,一定剂量下可引起骨髓微核和睾丸精母细胞染色体畸变率增加 ,提示它是一种可能致突变物     

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.     

Die sogenannte Vinylchlorid-Krankheit—eine berufsbedingte Systemsklerose?

Zusammenfassung Es wurden 13 Arbeiter untersucht, die zwischen 1 3/4 und 18 Jahren in einem PVC-herstellenden Betrieb beschäftigt waren. 8 von ihnen wiesen sklerodermieartige Hautveränderungen (Abb. 2) auf, die histologisch charakterisiert sind durch Verbreiterung und Homogenisierung der kollagenen Faserbündel (Abb. 3 u. 4) sowie Fragmentation und Rarefizierung der elastischen Fasern (Abb. 5). Bei 7 Patienten bestanden trommelschlegelartige Auftreibungen einzelner Fingerendphalangen (Abb. 1). 11 Patienten zeigten Durchblutungsstörungen der Extremitäten (4 von diesen ein Raynaud-Syndrom) und 6 Patienten Acroosteolysen einzelner Fingerendphalangen (Abb. 6, Tabellen 1–3).Darüber hinaus bestand bei allen Patienten eine Thrombocytopenie, bei 12 Patienten eine Splenomegalie, bei 11 Patienten eine Einschränkung der Leberfunktion (erhöhte BSP-Retention). An der Leber ließ sich histologisch bei den 5 laparoskopierten Patienten eine deutliche Fibrosierung der Portalfelder nachweisen. Bei 4 Patienten bestanden Oesophagusvaricen (Tabellen 4 u. 5). 8 Patienten zeigten eine Partialinsuffizienz mit Hinweisen für vorwiegend restriktive Veränderungen.Die hier beschriebenen Veränderungen gehen weit über das bisher bekannte Acroosteolysesyndrom hinaus. Es wird der dringende Verdacht geäußert, daß langfristige Vinylchlorid-Exposition dieses komplexe Krankheitsbild verursacht. Daher wird für diese systemische Krankheit die Bezeichnung Vinylchlorid-Krankheit vorgeschlagen.Wir danken Frau E. Voigtländer für die Herstellung der klinischen und histologischen Abbildungen.     

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.