纳米氧化镁对小鼠血清生化指标的影响

目的探讨纳米镁材料对小鼠血清生化指标的影响。方法按照固定剂量(5g/kg)法以镁粉、微米氧化镁和纳米氧化镁一次经口灌胃。14d后处死动物取血清观察常规生化指标的变化。结果纳米氧化镁组小鼠血清LDH和ALP明显低于微米氧化镁组(P<0.05),但与对照组相比无明显变化(P>0.05)。结论纳米氧化镁对血清LDH和ALP的影响与微米氧化镁材料有明显差别,其生化毒性作用可能与微米氧化镁材料有所不同。     

纳米铁、纳米氧化锌和纳米氧化镁对小鼠血清乳酸脱氢酶和α-羟丁酸脱氢酶活性的影响

目的探讨纳米铁(Fe)、纳米氧化锌(ZnO)和纳米氧化镁(MgO)材料对小鼠血清乳酸脱氢酶(LDH)和α-羟丁酸脱氢酶(α-HBDH)活力的影响。方法分别以5g/Kg·wt剂量的纳米(Nano-)或微米(Micro-)粒径Fe、ZnO和MgO给小鼠一次经口灌胃,14d后处死取血分离血清分析LDH和α-HBDH活性变化。结果Nano-和Micro-Fe染毒小鼠血清LDH活力均比对照组明显降低(P<0.05),但Nano-Fe和Micro-Fe组小鼠血清LDH差异无显著性(P>0.05);对照、Nano-Fe和Micro-Fe三组小鼠血清α-HBDH差异无显著性(P>0.05)。Nano-MgO组小鼠血清LDH比对照组有所升高,但差异无显著性(P>0.05)。Micro-MgO组小鼠血清LDH比对照组和Nano-MgO组有明显升高(P<0.05);对照、Nano-MgO和Micro-MgO三组小鼠血清α-HBDH差异则无显著性(P>0.05)。两种粒径ZnO染毒组小鼠血清LDH和α-HBDH比对照组有显著性升高(P<0.05),其中Micro-ZnO组小鼠血清LDH和α-HBDH活力升高的更为显著(P>0.05)。结论Nano-Fe、Nano-ZnO和Nano-MgO材料对小鼠血清LDH及α-HBDH活性的影响与相应微米粒径材料有所不同。     

纳米氧化铝对小鼠血清生化指标的影响

目的探讨纳米氧化铝(nano-A l2O3)对小鼠血清生化指标的影响。方法30只CD小鼠随机分为对照、nano-A l2O3和微米氧化铝(m icron-A l2O3)3组,以5 g/kg nano-A l2O3或m icron-A l2O3一次经口灌胃,14 d后处死观察血清生化指标的变化。结果nano-A l2O3组小鼠血清尿酸(UA)明显低于m icron-A l2O3组;m icron-A l2O3组丙氨酸转氨酶(ALT)明显低于nano-A l2O3组(P<0.05)。nano-A l2O3组小鼠血清乳酸脱氢酶(LDH)、α羟丁酸脱氢酶(HBDH)和UA与对照组相比有明显降低,碱性磷酸酶(ALP)、三酰甘油(TC)和葡萄糖(GLU)明显升高(P<0.05);总胆固醇(TG)、高密度脂蛋白胆固醇(HDL-C)有所升高,但与对照组相比差异无显著性(P>0.05)。与对照组相比,m icron-A l2O3组小鼠血清ALT、UA和白蛋白(ALB)明显降低,TG、TC和HDL-C显著升高(P<0.05)。结论nano-A l2O3对小鼠血清生化指标的影响与m icron-A l2O3有所不同。     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

纳米和微米二氧化钛急性经口毒性的比较

目的 探讨小鼠经口灌胃纳米二氧化钛后的急性毒性反应.方法 以5 g/kg剂量分别用纳米二氧化钛和微米二氧化钛单次经口灌胃染毒小鼠,观察14 d后处死,比较纳米二氧化钛和微米二氧化钛对小鼠体重、摄食量、血清生化指标及脏器系数的影响.结果 纳米二氧化钛对小鼠体重、脏器系数没有明显影响;实验期间,小鼠的摄食量逐渐增加;纳米二氧化钛染毒雌性组天冬氨酸转氨酶(AST)活力明显低于微米二氧化钛组,差异有统计学意义(P＜0.01),且肌酐(Cr)、尿素氮(BUN)与微米二氧化钛组、对照组相比,差异亦有统计学意义(P＜0.05).微米二氧化钛雌性组肌酸激酶(CK)活力明显高于对照组;纳米二氧化钛雄性组CK、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(α-HBDH)活力明显高于微米二氧化钛组,微米二氧化钛雄性组LDH、α-HBDH活力明显低于对照组,纳米二氧化钛雄性组CK活力明显高于对照组,差异均有统计学意义(P＜0.05).结论 纳米二氧化钛染毒未见明显的急性毒性反应,但对血液生化指标可能有一定的影响,且与微米二氧化钛的影响不同.     

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.