高效液相色谱法检测谷物中赭曲霉毒素A的方法评价与应用

目的:评价高效液相色谱定量检测谷物中赭曲霉毒素A的分析方法,为监测粮谷类食品中赭曲霉毒素A的污染水平提供技术支持。方法:利用液-液分离前处理技术,选用C18反相柱(250×4.6 mm),以乙腈:水:乙酸=99:99:2为流动相,流速1 ml/min,荧光检测器(激发波长333 nm,发射波长460 nm)定量,柱温25℃。结果:以准确度和精密度评价该方法,其中变异系数均低于10%,回收率介于77.61%~95.66%之间。结论:与文献中所采用免疫亲和柱净化样品的方法比较,本法操作简便、灵敏度高、重现性好、结果可靠、经济,可用于谷物中赭曲霉毒素A定量检测。     

用免疫学方法调查分析腊肉制品赭曲霉毒素A及其风险评估

目的:建立腊肉制品中赭曲霉毒素A免疫学检测的前处理方法,在对深圳市民膳食结构调查的基础上,对腊肉制品中的赭曲霉毒素污染进行了风险评估.方法:用免疫学方法检测40份市场腊肉制品.结果:从40份腊肉制品中检测9份含有OTA,平均污染程度为0.2768μg/kg.25份腊猪肉中有8份检出赭曲霉毒素A,污染程度在0～1.07 μg/kg;10份鸭肉中有1份检出赭曲霉毒素A,浓度为0.94 μg/kg;5份鸡肉均未检出赭曲霉毒素A.结论:本次检测的腊肉制品中,赭曲霉毒素A(OTA)含量最高的为1.07 oee'ks,表明市场上腊肉制品中OTA毒素污染水平不高,显示该产品风险较低.     

赭曲霉毒素A免疫学检测方法的研究

目的 建立敏感、特异和快速针对赭曲霉毒素A的酶联免疫吸附试验检测方法，研制具有我国自主知识产权的快速检测试剂盒。方法 利用B细胞杂交瘤技术，建立能够分泌抗赭曲霉毒素A单克隆抗体的杂交瘤细胞株，并获得抗赭曲霉毒素A单克隆抗体。结果 建立赭曲霉毒素A的间接竞争抑制性酶联免疫吸附试验测定方法(ELISA)。该方法的最低检出浓度为0.5ng/ml，线性范围2～500ng/ml，线性方程Y=0.272X 1.07(r=0.9978)。方法的加标回收率为79.0％～119.7％。利用该方法对北京市售的大米、小麦样品进行检测。结果表明．小麦样品的污染率为60.71％，最大值为8.26μg/kg；大米样品的污染率为17.86％，最大值为3.44μg/kg。结论 该方法简单、快速、灵敏。完全可以满足实际工作的需要。     

玉米中黄曲霉毒素B1等3种真菌毒素的高效液相色谱测定法

目的建立玉米中黄曲霉毒素B1、玉米赤霉烯酮和赭曲霉毒素的高效液相色谱测定法。方法玉米样品经甲醇水溶液(V/V=80∶20)提取后,以提取液为分散剂,三氯甲烷为萃取剂,黄曲霉毒素B1、玉米赤霉烯酮和赭曲霉毒素经液液分散式微萃取富集净化,以C18色谱柱为分离柱,以乙腈和1%乙酸水溶液为流动相梯度洗脱分离后,采用变波长的方法对三种毒素进行检测。结果黄曲霉毒素B1、玉米赤霉烯酮和赭曲霉毒素的线性范围分别为:1.00~100 ng/ml(r=0.998 5)、5.00~1 000 ng/ml(r=0.999 6)和1.00~100 ng/ml(r=0.999 3),检出限分别为:0.1、1.0和0.3μg/kg,平均加标回收率范围:82.5%~99.3%,RSD10%(n=6)。结论该方法快速、灵敏、准确可靠,适用于玉米样品中黄曲霉毒素B1,玉米赤霉烯酮和赭曲霉毒素的同时检测。     

固相萃取-高效液相色谱检测啤酒中赭曲霉毒素A

目的建立一种啤酒中赭曲霉毒素A的分析检测方法.方法使用SPE-C18固相萃取,C18反相柱(250×4.6 mm)分离,乙腈-水-乙酸(99992)为流动相,荧光检测器(激发波长333 nm,发射波长460 nm)检测.结果啤酒不同水平的加标回收率为72.8%～87.0%,RSD均小于8.6%.并用该法测定了市售三种啤酒,均在检出限以下.赭曲霉毒素A标准溶液浓度0～200 ng/ml与峰面积呈良好线性关系,线性相关系数为0.9996.根据三倍噪声法.该法检出限为0.023 ng/ml.结论使用SPE-C18柱极大地简化了样品预处理手续,可建立一种简便、快速、准确、实用的啤酒中赭曲霉毒素A的分析方法.     

HPLC法快速检测咖啡及粮食中赭曲霉毒素A

样品经粉碎后以乙腈－１％磷酸（９９＋１）提取，过滤后取滤液通过ＰＳＡ固相萃取小柱，洗脱后减压蒸干，用乙腈－水（４＋６）溶解，２０μｌ进色谱柱，荧光检测器检测。结果：咖啡、燕麦、大麦、玉米各一份，花生、黑麦２份检出赭曲霉毒素Ａ。其余样品未检出。本法对大米、玉米、小麦、大麦等回收率均在９０％以上，最低检测限为０．０５μｇ／ｋｇ。结论：使用ＰＳＡ柱可极大简化分析手续，使方法快速、简便、准确，同时不使用对人有害、对环境有污染的有机溶剂，适用于咖啡及各类粮食及制品中赭曲霉毒素的测定，并能实现赭曲霉毒素Ａ、Ｂ的同时测定     

植物油中赭曲霉毒素和伏马毒素的污染调查分析

目的了解植物油中赭曲霉毒素(OTs)和伏马毒素(FBs)的污染状况。方法从超市采集植物油样品,利用液相色谱-串联质谱法,检测样品中的赭曲霉毒素和伏马毒素含量,并进行分析。结果 39份植物油样品中OTA污染最为严重(污染率为48.7%),OTB次之(33.3%),FB_1(15.4%)和FB_2(10.3%)检出较少,FB_3无检出。各毒素检出含量均低于国内安全限量,OTA最高检出水平(花生油样品)为0.36μg/kg,OTB最高检出水平(花生油样品)为0.28μg/kg。讨论目前植物油中赭曲霉毒素污染较其他毒素普遍,花生油污染水平相对高些,但总体上各毒素污染水平较低,不存在超标现象。     

霉变谷物中霉菌毒素的污染调查

应用酶联免疫吸附测定法和薄层色谱法,对安徽、河南部分地区1991年因特大洪涝灾害造成粮食霉变而引起食物中毒的小麦和大米样品,进行了霉菌毒素[黄曲霉毒素B_1(AFB_1)、脱氧雪腐镰刀菌烯醇(DON)、T-2毒素(T-2)及赭曲霉毒素A(OA)等]的检测。在测定的样品中,检出了高含量的DON和T-2。其中,霉变小麦中,T-2的污染阳性率为96.9%。最高含量为1064.4μg/kg,平均含量为212.1μg/kg;6份霉变大米中,T-2平均含量达532.0μg/kg。     

HPLC法测定谷类食品中的赭曲霉毒素A

目的:建立谷类食品中赭曲霉毒素A的HPLC检测方法。方法:样品经提取、过免疫亲和柱净化后,用高效液相色谱-荧光检测器进行分析。结果:赭曲霉毒素A在1~20 ng/m l范围内线性关系良好,r0.999。回收率在80%~110%之间,定量限为1μg/kg,检测限为0.3μg/kg。结论:该方法快速、简便、准确,可作为谷类食品中赭曲霉毒素A定量测定的有效手段。     

固相萃取-超高效液相色谱-串联质谱法测定葡萄酒中赭曲霉毒素A和赭曲霉毒素α

目的 建立使用同位素内标法定量测定葡萄酒中赭曲霉毒素A和赭曲霉毒素α的超高效液相色谱-串联质谱法。方法 葡萄酒样品经5%氨水调至pH 9.0后,用MAX固相萃取小柱富集。以乙腈和5 mmol/L乙酸铵溶液为流动相,采用等度洗脱方式在ACQUITY BEH C_(18)(100 mm×2.1 mm,1.7μm)色谱柱上分离,以电喷雾正离子模式进行质谱检测,内标法定量。结果 赭曲霉毒素A和赭曲霉毒素α在1.0～50.0μg/L范围内,线性关系良好,r分别为0.9996和0.9993,方法的检出限均为0.10μg/kg,定量限均为0.35μg/kg。加标浓度0.35、2.00和10.00μg/kg时,方法的平均回收率为88.6%～108.0%,相对标准偏差为2.1%～9.2%(n=6)。结论该方法前处理简单、灵敏度高、准确、可靠,适用于葡萄酒中赭曲霉毒素A和赭曲霉毒素α的测定。     

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.