健力胶囊对正常小鼠免疫功能的影响

[目的]观察健力胶囊对正常小鼠免疫功能的影响。[方法]分别经口给予BALB／c小鼠250、500、1500mg／kg体重三个剂量的健力胶囊，30d后测定小鼠脏器／体重比值、细胞免疫功能、体液免疫功能、单核一巨噬细胞功能和NK细胞活性。[结果]各剂量组对小鼠脾／体重比值、碳廓清能力、腹腔巨噬细胞吞噬鸡红细胞的能力均无影响；1500mg／kg体重剂量组能升高小鼠胸腺／体重比值和小鼠血清溶血素抗体水平，能促进抗体生成细胞的生成，并能增强ConA诱导的脾淋巴细胞增殖能力和小鼠NK细胞活力；500、1500mg／kg体重剂量组均能明显增强DNFB诱导的小鼠迟发型变态反应。[结论]健力胶囊具有增强小鼠免疫功能作用。     

环磷酰胺和氢化可的松建立免疫抑制模型方法比较

目的比较利用环磷酰胺(CP)和氢化可的松(HY)两种药物诱导建立小鼠免疫抑制模型的方法。方法设立CP-1组、CP-2组、CP-3组和HY组,相对应地设4个阴性对照组。CP-1组于第1、2、3、9、16和23天腹腔注射80mg/kg CP;CP-2组第1、3、5、7和9天腹腔注射50mg/kg CP;CP-3组d1、d2腹腔注射40mg/kg CP;HY组d1、d3、d5、d7和d9肌内注射40mg/kg HY。阴性对照-1、2、3组腹腔注射等剂量生理盐水,阴性对照-4组肌内注射等剂量生理盐水。分别于第29、11、7和10天测定各项免疫指标。结果CP组小鼠胸腺指数、抗体生成细胞数、半数溶血值(HC50)、白细胞计数与阴性对照组比较均降低(P<0.05)。HY组小鼠脾指数、胸腺指数、碳廓清吞噬指数、腹腔巨噬细胞吞噬荧光微球功能、NK细胞活性、迟发型变态反应、白细胞计数与阴性对照组比较均降低(P<0.05)。结论 CP和HY均可建立小鼠免疫抑制模型,各种指标对两种受试物的敏感性不同。     

维生素E琥珀酸酯对荷瘤小鼠相关免疫功能的影响

目的 探讨维生素E琥珀酸酯(VES)对荷瘤小鼠相关免疫功能的影响.方法 将人宫颈癌Hela细胞于裸鼠皮下接种,建立荷瘤小鼠模型.将24只雌性荷瘤小鼠随机分为溶剂对照组(CON)、低剂量处理组(VES40mg/kg)和高剂量处理组(VES 80mg/kg),每组8只,隔日腹腔注射入裸鼠体内、测量并观察各组荷瘤小鼠体重及生...     

灵芝灰树花复合多糖对化疗所致免疫抑制和免疫功能的影响

目的观察灵芝灰树花多糖(LHP)对环磷酰胺(Cy)所致免疫抑制小鼠和正常小鼠免疫功能的影响及其作用机制。方法环磷酰胺(Cy)实验:小鼠随机分为正常、模型、贞芪扶正胶囊(ZQFZ)及LHP低、中、高剂量(60,120,320 mg/kg)6组,连续灌胃5 d,灌胃第二日除正常组外,其他各组腹腔注射Cy 50mg/kg,测定胸腺指数(TI)、脾指数(SI)和白细胞数;正常小鼠免疫功能实验:小鼠随机分为对照及LHP低、中、高(60,120,320 mg/kg)4组,连续灌胃30 d。测定小鼠迟发型变态反应(DTH)、脾淋巴细胞转化能力、抗体生成细胞数、半数溶血值(HC50)、巨噬细胞吞噬能力。结果正常小鼠免疫功能实验,LHP中、高剂量组能提高小鼠DTH、淋巴细胞增殖能力和HC50;低、中剂量组能增强小鼠产生抗体生成细胞的能力;高剂量组能提高小鼠腹腔巨噬细胞吞噬能力。环磷酰胺实验,LHP中、高剂量组能显著提高TI、SI及白细胞数量。结论 LHP能够逆转化疗药物引起的免疫抑制和增强机体免疫功能。     

微囊藻毒素对小鼠免疫功能的影响

[目的]探讨微囊藻毒素(microcystin,MC)对小鼠免疫功能的影响。[方法]清洁级ICR雄性小鼠40只随机分成4组,各染毒组分别腹腔注射8μg/kg、16μg/kg和24μg/kg的MC-LR,对照组腹腔注射等量生理盐水,连续7天,检测迟发型超敏反应(DTH)、半数溶血值(HC50)、白细胞计数和分类及脏器指数。[结果]与对照组相比,低剂量染毒组可使脾脏肿大(P<0.05),高剂量染毒组可使胸腺萎缩(P<0.05);在迟发性超敏反应和半数溶血值实验中,中高染毒组可使小鼠的足垫肿胀度和HC50下降(P<0.05);微囊藻毒素各染毒组还可引起白细胞数量下降(P<0.05),中高剂量组可降低淋巴细胞的比例(P<0.05)。[结论]微囊藻毒素可以对小鼠的免疫功能产生抑制。     

黄磷染毒对小鼠肝脏HSP70表达及NO的影响

[目的]观察黄磷染毒对小鼠HSP70表达及NO的影响，以探讨黄磷的毒作用机制，寻求黄磷中毒早期健康效应的生物标志物。[方法]通过对小鼠黄磷急性和亚急性毒理实验，应用生物化学和分子生物学的技术，选取176只健康雄性昆明种小鼠，体重18—22g，检测黄磷染毒对HSP70、一氧化氮(NO)、一氧化氮合酶(NOS)等指标的影响。染毒时，急性剂量．效应关系研究取小鼠32只，随机分成4组，低、中、高剂量组的染磷量分别为3、6、9mg／kg体重、对照组给予等量的花生油，腹腔注射染毒48h。时间--效应关系研究取小鼠64只，随机分成8组，实验组以9mg／kg体重的剂量一次性腹腔注射染毒，分别于染毒O、12、24、48h后断头处死小鼠，各组配以相应的对照组。亚急性毒理实验取小鼠80只，随机分成以下10组：O、1、2、3、4周时问组，以1．5mg／kg体重的剂量隔日腹腔注射染毒，每组配以相应的对照组。[结果]随染磷剂量的增高和染磷时间的延长，小鼠肝匀浆HSP70的表达也逐渐升高，急性染磷的HSP70表达升高比亚急性染磷明显；小鼠肝匀浆NOS活性和NO含量逐渐升高，并呈现良好的剂量--反应关系和时间--效应关系。[结论]在黄磷染毒过程中，HSP70对细胞起着很重要的保护作用。提示NOS和NO有可能作为黄磷中毒早期健康效应的生物标志物。     

外源核苷酸对小鼠免疫功能的影响

目的 :　本实验研究了日粮核苷酸促进免疫抑制小鼠的免疫功能恢复的作用。方法 :　选取 5～ 6 w龄 ,体重为 (2 0± 2 ) g的健康昆明种小鼠 6 0只 ,设 0、0 .0 5 %、0 .2 5 %三个核苷酸水平处理 ,每个处理中又分成正常和免疫抑制两个组 ,其中所有免疫抑制组在实验的第 2 d一次性大剂量腹腔注射环磷酰胺 (1 5 0 mg/kg bw) ,制备免疫抑制模型 ;正常组注射等同剂量的生理盐水。饲养 1 0 d后观察小鼠增重、脾脏和胸腺的脏器指数、脾淋巴细胞转化率、脾脏中抗 SRBC抗体形成细胞数量以及血清中抗 SRBC抗体水平。结果 :　日粮中添加核苷酸能够提高正常小鼠的增重 (P<0 .0 5 )、胸腺指数、淋巴细胞转化率 (P<0 .0 5 )及血清中抗体水平 ,极显著提高免疫抑制小鼠抗体水平 (P<0 .0 1 ) ,使抑制小鼠的各项指标接近正常。抗 SRBC抗体形成细胞数量没有显著变化。结论 :　在无核苷酸日粮中添加核苷酸能够促进正常小鼠免疫功能的提高 ,使免疫抑制小鼠免疫功能得到改善。     

对苯二胺对小鼠骨髓细胞致突变的影响

[目的]探讨对苯二胺(PPD)对小鼠骨髓嗜多染红细胞(PCE)致突变的影响。[方法]选择健康的昆明种小鼠50只,随机分为5组,每组10只。PPD高剂量组(215.00mg/kg),次高剂量组(107.50mg/kg),中剂量组(53.75 mg/kg),低剂量组(26.88mg/kg),采用腹腔注射0.2ml法染毒,每天1次,连续2d;给对照组注射生理盐水0.2ml。染毒后,测定并计算小鼠PCE的微核率;用单细胞凝胶电泳技术(SCGE)测定骨髓细胞的彗星细胞数和彗尾长度。[结果] PPD可致小鼠PCE微核率明显增加,引起拖尾细胞数相应增加。且都存在剂量-反应关系。[结论]PPD对小鼠PCE具有较强的致突变性。     

紫菜多糖对小鼠免疫功能影响的研究

[目的]观察紫菜多糖对正常小鼠免疫功能的影响。[方法]分别经口给予实验小鼠500、1000、2000mg/kg.bw3个剂量的紫菜多糖。30d后,测定小鼠脏器/体重比值、细胞免疫功能、体液免疫功能、单核-巨噬细胞功能、NK细胞活性和白介素-2的值。[结果]各剂量组对小鼠胸腺/体重比值、腹腔巨噬细胞吞噬鸡红细胞的能力、小鼠NK细胞活力和小鼠血清溶血素水平均无影响;500和2000mg/kg.bw剂量组能升高小鼠脾/体重比值;2000mg/kg.bw剂量组的紫菜多糖能明显增强DNFB诱导的小鼠迟发型变态反应、增强ConA诱导的脾淋巴细胞增殖能力、能促进抗体生成细胞的生成,并能促进体液细胞白介素2数值的增加;1000、2000mg/kg.bw剂量组使碳廓清能力增强。[结论]紫菜多糖具有增强小鼠免疫功能作用。     

稀土元素钬对小鼠3种抗氧化酶活力的影响

[目的]研究稀土元素钬对小鼠肝脏3种抗氧化酶活性的影响。找出剂量-效应关系。[方法]2次给小鼠腹腔注射氧化钬的盐酸溶液，相间24h，第2次注射24h后取肝脏检测超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）的活性，并进行统计分析，绘制出剂量-效应曲线。[结果]在10-40mg／kg体重剂量范围内3种酶的活性随剂量的增加而升高，40mg／kg体重酶活性达峰值，与阴性对照比较，t检验显示差异极显著（P〈0．01）；在40-160mg／kg体重剂量范围内3种酶的活性随剂量的增加而呈逐渐下降趋势。[结论]钬元素在低剂量下可能具有一定的抗氧化损伤作用，在高剂量时具有致抑制抗氧化酶活性的作用。     

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.