醋酸铅染毒对TK6细胞氧化损伤作用及亚硒酸钠的保护效应

目的 研究亚硒酸钠对醋酸铅致TK6细胞氧化应激损伤的保护效应。方法 培养TK6细胞,调整细胞密度为1×106/ml,试验分3组,正常对照组、醋酸铅染毒组和亚硒酸钠干预组,采用流式细胞仪检测细胞内活性氧簇(ROS)水平,硫代巴比妥酸（TBA）法检测细胞内丙二醛（MDA）含量和高度水溶性四唑盐（WST-1）法检测细胞内超氧化物歧化酶（SOD）活性。结果 在醋酸铅染毒和0.01 μg/ml的亚硒酸钠干预后,3组细胞内ROS含量、MDA含量和SOD含量的比较,差异均有统计学意义(F 分别为36.706,0.050,23.051,均P＜0. 01),其中醋酸铅染毒后,TK6细胞内ROS含量和MDA含量增高,与正常对照组比较差异有统计学意义（P＜0.01）,0.01 μg/ml的亚硒酸钠干预后,细胞内ROS含量和MDA含量下降,与醋酸铅染毒组比较差异有统计学意义（P＜0.01）;醋酸铅染毒后,TK6细胞内SOD含量降低,与正常对照组比较差异有统计学意义（P＜0.01）,0.01 μg/ml的亚硒酸钠干预后,SOD含量上升,与正常对照组比较差异无统计学意义（P＞0.05）,而与醋酸铅染毒组比较差异有统计学意义（P＜0.01）。结论 醋酸铅染毒对TK6细胞有氧化损伤作用, 0.01 μg/ml亚硒酸钠对醋酸铅氧化损伤毒性具有拮抗作用。     

血必净对百草枯诱导HK-2细胞凋亡的保护作用及机制研究

目的探讨血必净（xuebijing,XBJ）对百草枯（paraquat, PQ）诱导人近端肾小管上皮细胞系（human kidney cell line-2,HK-2）细胞凋亡的保护作用及机制。方法常规培养HK-2细胞。（1）PQ及XBJ干预后细胞生长抑制实验：PQ组分为0、200、400、800、1 600、3 200 μmol/L PQ组,干预24、48、72 h后检测细胞存活率;XBJ组分为0、5、10、20、40 mg/ml XBJ组,干预24、48、72 h后检测细胞存活率,以确定进行干预时合理的XBJ和PQ的浓度和作用时间。（2）XBJ拮抗PQ诱导HK-2细胞生长抑制实验：分为正常对照组、PQ组（800 μmol/L）、不同浓度XBJ＋PQ组（分别以5、10、20 mg/ml的XBJ预培养1 h后以800 μmol/L的PQ继续培养）,各组分别培养24、48、72 h后检测细胞存活率。（3）将HK-2细胞分为正常对照组、PQ组（800 μmol/L的PQ作用24 h）、PQ＋XBJ组（10 mg/ml的XBJ预处理1 h后以800 μmol/L的PQ作用24 h）、XBJ对照组（10 mg/ml的XBJ作用24 h）,用流式细胞仪检测细胞凋亡情况,蛋白免疫印迹法检测各组细胞内Bcl-2和BAX的蛋白表达情况,caspase-3及caspase-9活力试剂盒检测细胞内caspase-3及caspase-9活力。结果（1）PQ能明显降低HK-2细胞的存活率,并且呈现出时间和浓度依赖性,其中800 μmol/L的PQ作用24 h后HK-2细胞的存活率约为55%;20 mg/ml以下的XBJ在72 h内对HK-2细胞的存活率无明显影响。（2）与PQ组比较,PQ＋XBJ组HK-2细胞的存活率明显升高,差异有统计学意义（P〈0.05）。（3）与正常对照组比较,PQ组细胞凋亡率明显增加,差异有统计学意义（P〈0.05）。与PQ组比较,PQ＋XBJ组细胞凋亡率明显降低,差异有统计学意义（P〈0.05）。（4）与正常对照组比较,PQ组细胞内Bcl-2蛋白表达明显较低,BAX蛋白表达明显升高,差异有统计学意义（P〈0.05）;与PQ组比较,PQ＋XBJ组细胞内Bcl-2蛋白表达明显升高,BAX蛋白表达明显降低,差异有统计学意义（P〈0.05）。（5）与正常对照组比较,PQ组细胞内caspase-3及caspase-9活力明显升高,差异有统计学意义（P〈0.05）;与PQ组比较,PQ＋XBJ组细胞内caspase-3及caspase-9活力明显降低,差异有统计学意义（P〈0.05）。结论XBJ（10 mg/ml）对PQ（800 μmol/L）诱导的HK-2细胞损伤有明显的保护作用,其可以通过减轻PQ诱导HK-2细胞凋亡,来提高细胞的存活率。     

百草枯诱导小鼠脑小胶质细胞的炎症反应

目的观察百草枯(PQ)诱导小鼠脑小胶质(BV2)细胞株的炎症反应。方法取处于对数生长期的BV_2细胞,分别暴露于终浓度为0(阴性对照)、20、40、80μmol/L的PQ溶液继续培养6、12、24、48 h。检测细胞活性和炎症因子[肿瘤坏死因子α(TNF-α)、白细胞介素-6(interleukin 6,IL-6)、IL-1β及活性氧(ROS)]水平。结果与阴性对照组比较,各剂量PQ染毒组BV_2细胞TNF-α、IL-1β、IL-6和ROS的水平及细胞抑制率均较高,差异均有统计学意义(P0.05);与染毒6 h比较,染毒12、24、48 h时BV_2细胞TNF-α、IL-1β、IL-6和ROS的水平及细胞抑制率均较高,差异均有统计学意义(P0.05)。且随着PQ染毒剂量的升高和染毒时间的延长,BV_2细胞的抑制率及TNF-α、IL-1β、IL-6和ROS水平均呈上升趋势。结论PQ能活化小鼠小胶质细胞,使其分泌炎症因子,同时诱导氧化损伤,加重细胞毒性作用。     

2,2'''',4,4''''-四溴联苯醚对原代新生大鼠海马细胞氧化应激、DNA损伤和凋亡的影响

目的 探讨2,2',4,4'-四溴联苯醚(2,2',4,4'-tetrabromodiphenyl ethers,PBDE-47)对原代新生大鼠海马细胞氧化应激、DNA损伤和凋亡的影响.方法 原代培养的新生大鼠海马细胞暴露于10、20、40μg/ml PBDE-47,每组3个平行样,24h后,检测乳酸脱氢酶(LDH)漏出率,细胞内丙二醛(MDA)和还原型谷胱甘肽(GSH)含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力、活性氧(ROS)水平以及DNA损伤和细胞凋亡情况.结果 与对照组比较,20和40μg/ml组LDH漏出率升高,差异有统计学意义(P＜0.05).各染毒组MDA含量均高于对照组,GSH-Px活力均低于对照组,且20和40μg/ml组与对照组比较,差异均有统计学意义(P＜0.05);10、20、40μg/ml组GSH含量和SOD活力均低于对照组,差异有统计学意义(P＜0.05),但各染毒组之间差异无统计学意义(P＞0.05);20和40μg/ml组细胞内ROS水平高于对照组,差异均有统计学意义(P＜0.05).10、20、40μg/ml组尾部DNA百分率和Oliver尾矩均高于对照组,差异均有统计学意义(P＜0.05);20和40μg/ml组细胞凋亡率均高于对照组,差异有统计学意义(P＜0.05),且呈上升趋势.相关分析表明,海马细胞DNA损伤、凋亡百分率与ROS水平呈正相关(r值分别为0.982,0.998,P＜0.05),细胞凋亡百分率与DNA损伤呈正相关性(r=0.967,P＜0.05).结论 PBDE-47可致原代新生大鼠海马细胞氧化应激和诱导细胞DNA损伤和凋亡,呈现一定的神经毒性.     

亚砷酸钠对人支气管上皮细胞的氧化损伤作用

目的 探讨不同浓度亚砷酸钠对永生化人支气管上皮细胞氧化损伤的影响.方法 体外培养永生化人支气管上皮(HBE)细胞,加入终浓度为0～50000 μmol/L的亚砷酸钠溶液暴露24h,测定细胞活性;加入终浓度为0～6μmol/L的亚砷酸钠溶液暴露24h,测定活性氧(ROS)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活力及细胞DNA链断裂情况.结果 与对照组比较,各浓度亚砷酸钠染毒组HBE细胞内ROS、MDA含量和Olive尾矩均显著升高,细胞存活率和SOD活力均显著下降,差异有统计学意义(P＜0.05);且随着亚砷酸钠染毒浓度的升高,HBE细胞内MDA、ROS含量和Olive尾矩均呈明显的上升趋势(P＜0.05),细胞存活率和SOD活力均呈明显的下降趋势(P＜0.05).结论 亚砷酸钠可以诱导HBE细胞氧化损伤增加,提示氧化应激可能是亚砷酸钠致HBE细胞毒作用机制之一.     

百草枯致大鼠急性肺损伤时肺组织c-Jun氨基末端激酶和c-Jun的变化

目的 探讨百草枯(paraquat,PQ)致大鼠急性肺损伤时肺组织中c-Jun氨基末端激酶(JNK)和c-Jun的变化.方法 将46只大鼠随机分为对照组(10只)、PQ组、PQ+锌原卟啉(ZnPP)组和PQ+氯血红素(Hm)组(每组各12只).PQ组大鼠腹腔注入PQ(25 mg/ks)制造PQ中毒模型;对照组大鼠腹腔注入等量生理盐水;PQ+ZnPP组大鼠在注入PQ前10min注入ZnPP(10mg/kg,10ms/ml);PQ+Hm组大鼠在注入PQ前10min注入Hm(10mg/kg,10mg/ml).不同处理后3 d,取肺组织常规HE染色和取血测定血浆中丙二醛(MDA)含量;检测肺组织中CO含量;反转录一聚合酶链反应(RT-PCR)检测肺组织血红素氧合酶.1(HO-1)mRNA的表达;Western免疫印迹分析肺组织JNK和c-Jan磷酸化的情况.结果 PQ组、PQ+ZnPP组和PQ+Hm组血浆中MDA含量、肺组织中CO含量均明显高于对照组,差异有统计学意义(P＜0.05或P＜0.01),与PQ+ZnPP组比较,PQ+Hm组MDA含量降低,而肺组织中CO含量明显升高,差异均有统计学意义(P0＜.01). PQ组、PQ+ZnPP组和PQ+Hm组的肺组织HO-1mRNA表达、JNK(55.24±9.34、38.15±10.71、128.55±19.43)及c-Jun(23.16±4.85、15.49±3.13、44.89±10.37)磷酸化相对水平较对照组均明显升高,差异有统计学意义(P＜0.01),PQ+Hm组肺组织的HO-1mRNA表达明显高于PQ组,PQ+Hm组JNK及c-Jun磷酸化水平高于PQ组和PQ+ZnPP组,而PQ+ZnPP组JNK及c-Jun磷酸化水平与PQ组相比又有所降低,差异均有统计学意义(P＜0.01或P＜0.05).结论 在PQ致大鼠急性肺损伤时,内源性CO产生增加.肺组织中JNK和c-Jan的磷酸化水平明显升高.     

不同剂量米非司酮诱导Nrf2基因表达对百草枯致A549细胞损伤的影响

目的 观察不同剂量米非司酮(RU486)诱导Nrf2基因表达对百草枯(PQ)致A549细胞毒性影响.方法 Ad-RUNff2感染的A549细胞,在给予10-10、10-9、10-8、10-7 mol/L的RU486诱导表达6h后,加入浓度为10-3 mol/L的PQ培养48 h,用实时定量聚合酶链式反应(real-time PCR)法和凝胶迁移率试验( EMSA)检测不同浓度RU486诱导的Nrf2表达情况;Real-timePCR、ELISA检测不同浓度Nrf2对PQ致A549细胞损伤炎症因子白细胞介素(IL)-6、IL-10、肿瘤坏死因子(TNF)-α,凋亡因子半胱氨酸天冬氨酸蛋白酶( Caspase )-3、Caspase-9、细胞色素c(Cyt C)基因相对表达量和蛋白含量的影响.用化学比色法检测氧化因子过氧化氢酶(CAT)、丙二醛(MDA)蛋白含量.结果 Nrf2基因相对表达量及蛋白表达均随RU486浓度增高而增高,其中以RU486浓度为10-7 mol/L时最高,与PQ中毒组及空白对照组的差异有统计学意义(P＜0.01,P＜0.05).随RU486浓度降低,IL-6、TNF-α的基因相对表达量及蛋白含量升高,在RU486 10-7 mol/L时最低,与PQ中毒组及空白对照组的差异有统计学意义(P＜0.01,P＜0.05);IL-10的变化则相反.随RU486浓度降低,Caspase-3、Caspase-9、Cyt C基因相对表达量升高,10-7 mol/L时最低,与PQ中毒组及空白对照组的差异有统计学意义(P＜0.01,P＜0.05).随着RU486浓度的增高,CAT 蛋白含量增高,RU486浓度为10-7 mol/L时含量最高,与PQ中毒组及空白对照组的差异有统计学意义(P＜0.05),MDA含量的变化则相反.结论 RU486诱导Nrf2基因表达能促进A549细胞的氧化-抗氧化系统平衡,并抑制炎症因子、凋亡因子,对PQ致A549细胞损伤有保护作用.     

不同波段电磁辐射对淋巴细胞的损伤效应

目的 探讨电磁脉冲(EMP)、S波段高功率微波(S-HPM)和X波段高功牢微波(X-HPM)3种不同波段的电磁波对Raji细胞的损伤效应.方法 采用流式细胞技术检测3种波段电磁波辐照后6h Raji细胞周期、凋亡率和坏死率;采用共聚焦显微镜检测辐照后6 h Raji细胞Ca2+浓度.结果 各辐射组S期细胞数均明显少于对照组.G0/G1期细胞数均明显多于对照组,差异有统计学意义(P＜0.05);X-HPM组G2/M期细胞数低于对照组,差异亦有统计学意义(P＜0.05).各辐射组细胞凋亡率均高于对照组,其中EMP组和X-HPM组与对照组的差异有统计学意义(P＜0.05,P＜0.01);辐射组间比较,EMP组和X-HPM组细胞凋亡率均明显高于S-HPM组,差异亦有统计学意(P＜0.05,P＜0.01).各辐射组细胞坏死牢均明显高于对照组,差异有统计学意义(P＜0.01);各辐射组间比较,EMP组坏死率明显高于SHPM组和X-HPM组,差异亦有统计学意义(P＜0.01).各辐射组细胞内Ca2+荧光强度均明显高于对照组,差异有统计学意义(P＜0.01);各辐射组间比较,EMP组和X-HPM组ca2+荧光强度均明显高于SHPM组,差异亦有统计学意义(P＜0.01).结论 3种波段电磁波对Raji细胞引起的损伤效应相似,但程度不同,以EMP组最严重,S-HPM组最轻,其机制可能与细胞内Ca2+超载有关.     

螺内酯对醛固酮诱导的大鼠肾小球系膜细胞氧化应激的影响

目的 观察螺内酯对醛固酮诱导的大鼠肾小球系膜细胞(mesangial cells,MCs)氧化应激的影响,探讨其肾脏保护机制.方法 体外培养大鼠MCs,设正常对照组、醛固酮(10-7 mol/L)刺激组、不同浓度螺内酯(10-7、10-8、10-9mol/L)干预组.以2',7'-二氯双氢荧光素二乙酸酯(2',7'-dichlorofluorescein diacetate,DCFH-DA)为细胞内H2O2的荧光探针标记细胞,采用流式细胞术检测系膜细胞内活性氧(reactive oxygen species,ROS)水平;采用比色法检测培养细胞上清液中丙二醛(malondialdehyde,MDA)的含量和超氧化物歧化酶(superoxide dismutase,SOD)活性.结果 与正常对照组比较,醛固酮刺激系膜细胞48 h后,细胞内ROS水平明显增加,上清液中MDA含量增高、SOD活性下降,差异均有统计学意义(均有P＜0.05).螺内酯干预可明显抑制醛固酮刺激下的系膜细胞的上述反应,差异均有统计学意义(均有P＜0.05),且呈浓度依赖性.结论 螺内酯可呈浓度依赖性地抑制醛固酮诱导的大鼠MCs氧化应激,该作用可能是其肾脏保护机制之一.     

钝顶螺旋藻藻蓝蛋白抗百草枯诱导大鼠肺纤维化的研究

目的 探讨钝顶螺旋藻(spirulina platensis)藻蓝蛋白(C-phycoeyanin,C-PC)对百草枯(paraquat,PQ)染毒诱导大鼠肺纤维化的治疗作用.方法 选取健康Wistar大鼠90只,随机分为正常对照组、模型组(PQ组)和藻蓝蛋白治疗组(C-PC组),每组30只.PQ组、C-PC组以PQ(50 mg/kg)一次灌胃染毒造模.造模后,正常对照组、PQ组大鼠每天给予生理盐水(1 ml/100 g)灌胃,C-PC组每天给予C-PC (50 mg/kg)灌胃,并在第1、3、7、14、28天各组随机取6只大鼠右肺下叶肺组织匀浆测羟脯氨酸(HYP)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活力;取左肺部分组织行HE染色、Masson染色进行病理观察,并用免疫组化方法观察肺组织中转化生长因子-β1(TGF-β1)、核因子-κB亚基p65(NF-κB p65)及肿瘤坏死因子-α(TNF-α)的表达.结果 各观察时点C-PC组大鼠肺组织中HYP和14、28 d MDA含量明显低于PQ组,差异有统计学意义(P＜0.05,P＜0.01).1、7、14、28 d时C-PC组大鼠肺组织中SOD活力明显高于PQ组,差异有统计学意义(P＜0.05,P＜0.01).PQ组和C-PC组肺组织中TGF-β1的表达及NF-κB p65和TNF-α表达明显高于正常对照组,C-PC组肺组织的TGF-β1表达及NF-κB p65和TNF-α表达明显低于PQ组,差异均有统计学意义(P＜0.05,P＜0.01).病理学观察显示C-PC能减轻PQ染毒大鼠肺泡炎和肺纤维化程度.结论 C-PC对PQ诱导的大鼠肺泡炎及肺纤维化有抑制作用.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

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.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

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.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

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.     

The risk of heat exhaustion at a deep underground metalliferous mine in relation to surface temperatures

The risk of heat exhaustion at a deep underground metalliferous mine was assessed in relation to thermal conditions prevailing on the surface. For each day of a 1-year prospective case series of heat exhaustion, surface 24-h mean wet and dry bulb temperatures were recorded. From this data, 24-h mean wet bulb globe temperatures were derived using certain assumptions. The three surface temperature variables were significantly higher on those days on which heat exhaustion occurred, compared to those days on which it did not occur (P < 0.001). The relative risk of heat exhaustion on days when the 24-h mean wet bulb globe temperature was in the range 26.0-28.0 degrees C was 4.82 (95% confidence interval 2.12-10.96). Surface temperature data could be used at this mine to warn miners about the risk of heat exhaustion.