制药废水致泥鳅遗传及生理毒性作用

目的 了解某制药厂处理废水的污染物遗传及生理毒性状况.方法 选用泥鳅为受试对象,进行微核外周血红细胞微核率、谷丙转氨酶、谷草转氨酶检测.结果 染毒6 d后,原液鱼外周红细胞微核率与对照组比较,增长了89%.同时,随药液浓度增加,肝脏谷丙转氨酶(PGT)和谷草转氨酶(GOT)活力下降,原液的酶活性值达到最低水平,均值分别为36.645 3和66.303 1,与对照相比降低了76.90%和80.61%,而血清GTP和GOT活力呈上升趋势,原液的酶活性值达到最高水平,平均值分别为501.042 3和639.167 0,与对照组比升高了83.34%和96.09%.结论 此制药厂废水致泥鳅有明显的遗传毒性与生理毒性.     

壬基酚对泥鳅的遗传毒性效应

为观察壬基酚对泥鳅的遗传毒性作用,将泥鳅分别为饲养于50、200、500、1000μg/L壬基酚染毒溶液中6、12、24、48h,并设空白对照(曝气脱氯自来水)组和溶剂对照(0.02％乙醇)组.采用微核试验统计微核细胞数及核异常细胞数,并计算微核率和核异常率.结果显示,与溶剂对照组比较,50μg/L壬基酚染毒24、48h以及200、500、1000μg/L壬基酚染毒6～48h泥鳅的红细胞微核率和核异常率均较高,差异有统计学意义(P＜0.05).随着壬基酚染毒浓度的升高以及染毒时间的延长,泥鳅红细胞的微核率和核异常率呈先升高后下降的趋势.提示较高浓度的壬基酚对泥鳅具有遗传毒性.     

郑州市某污水处理厂尾水毒性评价

目的探讨郑州市某污水处理厂进出水的急性毒性和遗传毒性。方法采集该厂进水、二级出水和三级出水,利用发光细菌毒性测试法检测进出水的急性毒性,利用蚕豆根尖微核试验检测进出水的遗传毒性。结果进水、二级出水和三级出水对发光菌的抑光率分别为(33.96±7.51)%、(14.32±7.36)%、(7.24±5.58)%,二级出水和三级出水对发光菌的抑光率低于进水(F=12.159,P=0.008)。蚕豆根尖微核细胞率分别为(12.67±2.08)‰、(6.33±1.53)‰和(2.67±0.58)‰,污染程度分别为重度污染、轻度污染和基本无污染,二级出水及三级出水蚕豆根尖微核细胞率低于进水(F=56.850,P<0.001)。结论进水经处理后急性毒性及遗传毒性显著下降,但对环境仍具有一定的生态风险性。     

亚硝酸钠对泥鳅红细胞的遗传损伤研究

[目的]研究亚硝酸钠在不同浓度和不同染毒时间对泥鳅红细胞的损害,观察改性竹炭-K对亚硝酸钠的吸附效果。[方法]用微核率评价亚硝酸钠对泥鳅的红细胞遗传损伤。[结果]亚硝酸钠的损害主要表现在微核率以及核变形率的增高,且在一定浓度范围内,随着浓度的升高和染毒时间的延长而越来越高。用改性竹炭-K对400mg/L的亚硝酸钠吸附处理,效果显著。[结论]亚硝酸钠对泥鳅的LD50为272mg/L;对泥鳅的遗传损伤表现为微核率和核变形率增高;改性竹炭-K对亚硝酸钠的吸附作用显著。     

铜离子诱发(歺又鱼)鲦鱼红细胞微核及核异常的研究

目的 通过(歺又鱼)鲦鱼红细胞研究铜离子的遗传毒性,寻找对诱变物敏感的鱼类.方法 选择120尾(歺又鱼)鲦鱼,随机分为8组,每组15尾,分别用Cu2 浓度为0.01、0.02、0.04、0.08、0.16、0.32、0.64、1.28 mg/L的CuSO4溶液染毒,染毒在同一规格的塑料箱内进行.对照组以纯净水饲养.每一浓度组在6、12、24、48 h时随机取鱼3尾(0.64mg/L组每次处理2尾),用纱布将鱼体表水分擦干.断尾取血,涂片,观察不同浓度、不同染毒时间铜离子对(歺又鱼)鲦鱼红细胞微核及核异常的影响.结果各 染毒组(歺又鱼)鲦鱼红细胞微核率及核异常率均低于对照组,差异有统计学意义(P＜0.05或P＜0.01).在12、24h时,在一定浓度(0.01～0.16 mg/L)范围内(歺又鱼)鲦鱼红细胞微核率与铜离子浓度成正相关,但当浓度过高(0.32、0.64 mg/L)时,微核率反而降低.当铜离子浓度较低(0.01～0.08 mg/L)时,微核率随染毒时间的延长而升高.结论 (歺又鱼)鲦鱼对诱变物敏感,可以作为微核实验的良好材料来检测诱变物的遗传毒性.     

纳米氧化铜对小鼠遗传毒性及氧化应激的研究

目的 研究纳米氧化铜对小鼠的遗传毒性及氧化应激水平.方法 30只小鼠随机分成对照组、50、150 mg/kg纳米氯化铜染毒组,染毒组分别一次性腹腔注射50、150 mg/kg纳米氧化铜,对照组给予含0.05％ Tween 80相同体积的生理盐水.于染毒前及染毒后24、48及72 h分别测定尾静脉外周血网织红细胞微核发生率和尿中8-羟基-脱氧鸟嘌呤核苷(8-OH-dG)水平.染毒72 h,处死小鼠,取肝、肾和股骨骨髓,分别提取DNA并测定DNA中8-OH-dG.结果 50 mg/kg染毒组48 h,150 mg/kg组24和48 h外周血网织红细胞微核发生率(3.1 1‰±1.46、4.25‰±0.43‰、5.42‰±0.76‰)比两组染毒前(1.55‰±0.39‰、1.11‰±0.19‰)及相应的对照组(1.55‰±0.28‰、1.00±0.67‰)明显升高,差异有统计学意义(P＜0.05或P＜0.01).与染毒前及对照组比较,各时间50、150 mg/kg染毒组尿8-OH-dG水平(ng/mg尿肌酐)均明显升高,差异有统计学意义(P＜0.05或P＜0.01).50和150 mg/kg组肝组织DNA中8-OH-dG水平(4.53±1.27、7.69±2.78)明显高于对照组(0.85±0.14),差异有统计学意义(P＜0.01).结论 纳米氧化铜对小鼠具有遗传毒性,并致其氧化应激水平升高.     

卷烟烟气抽提物对细胞遗传毒性及茶多酚干预作用

目的探讨卷烟烟气抽提物(CSE)对支气管上皮细胞(BEAS-2B)遗传毒性及茶多酚干预作用。方法以高、中、低3个浓度对支气管上皮细胞进行染毒,同时设立茶多酚干预组和空白对照组;采用彗星实验及γ-H2AX蛋白表达检测DNA损伤,以微核实验检测染色体损伤,并检测HPRT基因突变率。结果高剂量染毒组BE-AS-2B细胞彗星细胞数(130.5±1.6)个、彗星尾长(134.33±3.56)μm、尾部面积(7 798.43±43.45)μm2,均明显高于空白对照组(P<0.05),并呈剂量—效应关系;CSE低、中、高剂量染毒组BEAS-2B细胞中微核细胞分别为(22.4±3.2)、(38.6±1.8)、(79.6±2.4)个,均明显多于空白对照组的(6.2±1.5)个(P<0.05);CSC中、高剂量染毒组BEAS-2B细胞HPRT基因突变率分别为(0.802±0.040)‰、(1.058±0.002)‰,均明显高于空白对照组的(0.330±0.002)‰(P<0.05)。茶多酚对CSE诱发的DNA链断裂及微核细胞增多有明显抑制作用,并可有效降低HPRT基因突变率。结论 CSE具有细胞遗传毒性,茶多酚对其遗传毒性具有干预作用。     

甲基磺酸甲酯对人胚肺成纤维细胞遗传毒作用的影响

目的通过观察甲基磺酸甲酯(MMS)对人胚肺成纤维细胞(HLF)DNA损伤、微核形成及细胞周期改变情况,进一步提示MMS的遗传毒性。方法分别设空白对照组、溶剂对照组和5个MMS染毒组(1.0,2.0,4.0,8.0,16.0μmol/L),共2份,对HLF细胞染毒36 h后,1份直接用彗星试验检测DNA损伤,另一份继续培养24 h后进行微核试验及观察细胞周期改变情况。结果微核试验结果表明,各剂量组的微核率分别为2.0‰,2.0‰,4.0‰,5.5‰,9.0‰,10.5‰,21.0‰,核异常率分别为4.5‰,5.5‰,6.0‰,7.5‰、8.5‰,10.0‰,23.5‰,与空白对照组比较,染毒剂量大于4.0μmol/L的各组差异均有显著性(P<0.05)。各剂量组细胞DNA拖尾率分别为11%,13%,27%,39%,51%,73%,89%,彗星尾长分别为(6.17±1.14),(6.36±1.97),(23.27±3.56),(29.15±4.70),(36.22±7.05),(41.76±6.19),(57.34±9.13)μm。相关分析表明,微核率、核异常率、拖尾率和彗星尾长与染毒剂量间存在明显的剂量-效应关系,其中2.0,4.0,8.0,16.0μmol/L剂量组的微核率、核异常率、拖尾率和彗星尾长明显增加(P<0.05);且随着MMS剂量的升高,高度、重度DNA损伤的比例也逐渐增加。MMS染毒后,随着染毒剂量的增加,HLF细胞逐渐出现G1期阻滞,G2期细胞数增加。结论MMS可致HLF细胞DNA损伤、细胞微核形成增加及细胞周期改变。     

有机膨润土遗传毒性的体外试验研究

目的 体外试验研究有机膨润土的遗传毒性.方法 人B淋巴母细胞(HMy2.CIR)染毒0、1.88、3.75、7.50、15.00μg/ml有机膨润土24、48、72 h,并设硫酸钙(30μg/ml)和游离SiO2(30、240μg/ml)为阴性和阳性颗粒对照.用彗星试验和胞浆分裂阻滞微核试验(cytokinesis-block micronucleus,CBMN)检测有机膨润土颗粒部分和可溶性部分的遗传毒性.结果 彗星试验结果表明,有机膨润土组彗星尾部DNA百分含量(%tail DNA)随染毒剂量和时间的增加而增高,剂量为15.00 μg/ml、染毒时间24、48、72 h时的%tail DNA分别为3.20±0.19、4.63±0.88和9.49±1.31,均明显高于30μg/ml硫酸钙组(分别为1.40±0.11、1.37±0.22和0.90±0.16)和30μg/ml二氧化硅组(分别为1.83±0.21、1.41±0.27和2.48±0.25),差异均有统计学意义(P＜0.01).CBMN试验结果发现,有机膨润土组(除1.88μg/ml染毒24h外)微核率(MNF)均明显高于30μg/ml硫酸钙组(分别为1.33‰±0.58‰、1.33‰±1.15‰和1.33‰±0.58‰)和30μg/ml二氧化硅组的MNF(分别为2.00‰±0.00‰、1.68‰±0.58‰和2.33‰±0.58‰),差异有统计学意义(P＜0.01).2种试验结果还表明有机膨润土可溶性部分并不诱发遗传毒性.结论 体外试验有机膨润土可诱发人B淋巴细胞系DNA损伤和微核率增高,毒性主要来源于不可溶部分.     

芽孢菌肽的急性毒性和遗传毒性研究

目的研究芽孢菌肽的急性毒性和遗传毒性。方法以急性毒性试验、骨髓细胞微核试验和睾丸染色体畸变试验评估芽孢菌肽的急性毒性和遗传毒性。结果芽孢菌肽雌、雄小鼠急性经口LD50值及95%CI分别为5 010(3 080~8 140)mg/kg BW和7 940(4 670~13 500)mg/kg BW。骨髓细胞微核率为(2.2±0.4)‰~(2.6±0.6)‰,睾丸染色体畸变率为(0.20±0.45)%~(0.40±0.55)%,与溶剂对照相比,差异均无统计学意义(P值均0.05),结果均为阴性。结论在试验条件下,芽孢菌肽属实际无毒级,未见遗传毒性。     

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 occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

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.     

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.     

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.     

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.