高效液相色谱法测定保健食品中的番茄红素

目的:采用高效液相色谱法测定保健食品中的番茄红素(胶囊或片剂).方法:样品用水溶解破膜,以乙酸乙酯提取,用HPLC检测番茄红素的含量.结果:本方法线性范围为0.0～10.0μg/ml,最低检出浓度为0.1μg/ml,加标回收率为98.36%～104.8%.相对标准偏差为2.3%～4.2%.结论:本方法操作简单,灵敏度高,线性范围宽,不失为一种较好的测定方法.     

高效液相色谱法测定保健食品中的叶黄素

目的:建立测定保健食品中叶黄素含量的方法。方法:采用无水乙醇对试样进行提取,纯甲醇体系作为流动相,ODS C18柱,高效液相色谱(HPLC)进行分离检测。结果:方法的检出限为0.1μg/g,线性范围在0.3μg/ml～6.2μg/ml之间,RSD为5.9%,平均回收率为92%～105%。结论:该方法具有简便、快速、可靠、容易推广等优点,适用于液体、片剂、粉剂、胶囊、软胶囊样品的测定。     

工作场所空气中硫酸二甲酯的气相色谱快速测定

以硅胶管吸附空气中硫酸二甲酯,用丙酮解吸后毛细管柱气相色谱(FPD)测定。结果硫酸二甲酯浓度在0.3~5.0μg/ml范围内与峰面积的平方根线性关系良好,线性方程为:y=-2.8+12.4x(r=0.998)。检出限0.3μg/ml,若采集4.5 L空气样品,则最低检出浓度为0.07 mg/m3。平均加标回收率92.3%~97.8%;相对标准偏差(RSD)在2.3%~6.9%。本方法适用于工作场所空气中硫酸二甲酯浓度的测定。 更多还原     

营养强化剂类保健食品中生物素含量的测定

目的:采用HPLC测定营养强化剂类保健食品中生物素的含量。方法:样品采用水溶剂超声波提取方法,以Symmetry Shield RPC18柱为固定相,乙腈:0.05%三氟乙酸水溶液(pH=2.5)为流动相,检测波长为201 nm。结果:生物素与其它杂质均能达到基线分离,其色谱峰形好。生物素的浓度在2.0μg/ml～40.0μg/ml时与峰面积成良好的线性关系(Y=-666+1.02×105X,r=0.9999),平均回收率为94.5%～105%,方法精密度RSD为1.93%、和1.47%(n=6)。结论:所用方法简便,准确,重复性好,适用于营养强化剂类保健食品中生物素的测定。     

高效液相色谱法测定保健食品中阿魏酸含量的方法研究

目的:建立保健食品中阿魏酸的高效液相色谱测定方法。方法:采用WATERS Xterra RP18(4.6×250 mm,5μm)色谱柱分离;流动相为乙腈:0.5%冰醋酸=28:72(v/v);流速1.00 ml/min;2487紫外检测器322 nm测定。结果:阿魏酸在0.005μg/ml～80μg/ml时,浓度与峰面积呈良好的线形关系(r=0.9999),检出限为5.0μg/L,加标回收率在98.0%～100.8%之间,相对标准偏差RSD在1.10%～1.81%之间。结论:该方法简便、快速、准确,适用于保健食品中阿魏酸含量的测定。     

RP-HPLC法测定保健品葛根粉中葛根素的含量

目的以RP-HPLC法测定保健品葛根粉中葛根素的含量。方法以甲醇-乙腈-水(10∶10∶80)为流动相,在依利特Hypersil ODS柱(4.6 mm×200 mm,5μm),流速为1.0 ml/min,250 nm波长下进行测定,进样量10μl。结果葛根素在20μg/ml~200μg/ml时,浓度与峰面积呈良好的线性关系(r=0.999 9),加标回收率为99.37%~99.82%,最低检出限为2μg/ml,相对标准偏差RSD为0.03%~0.15%。结论本方法操作简单准确,可用于保健品葛根粉中葛根素的含量测定。     

高效液相色谱法同时测定保健食品中水飞蓟宾和五味子醇甲

目的建立保健食品中水飞蓟宾和五味子醇甲的高效液相色谱测定方法。方法样品经甲醇超声提取,被测物采用Poroshell 120 EC-C18(4.6 mm×100 mm,2.7μm)分离柱;流动相为甲醇-水,梯度洗脱,流速为0.7 ml/min;水飞蓟宾和五味子醇甲的紫外检测波长分别为287 nm和250 nm。根据保留时间定性,外标峰面积法定量。结果水飞蓟宾在0μg/ml~243.9μg/ml线性相关系数为0.999 7,方法检出限为1.82μg/ml,相对标准偏差(RSD)为0.84%(n=6),样品的加标回收率为97.4%~102.1%;五味子醇甲在0μg/ml~43.3μg/ml线性相关系数为0.999 6,方法检出限为0.48μg/ml,相对标准偏差(RSD)为0.56%(n=6),样品的加标回收率为97.4%~102.5%。结论该方法简单、快速、灵敏和准确,可用于保健食品中水飞蓟宾和五味子醇甲的测定。     

高效液相色谱-串联质谱法快速测定降压类中成药及保健食品中非法添加12种化学药物的研究

目的 建立一种快速、准确的高效液相色谱-串联质谱技术(LC-MS/MS)同时测定中成药与保健食品中非法添加的12种降压类化学药物。方法 样品经甲醇提取,超声处理后,采用LC-MS/MS法,以Agilent Eclipseplus C18(50 mm×2. 1 mm,1. 8μm)为色谱柱,0. 1%甲酸甲醇溶液(A)-0. 1%甲酸水溶液(B)为流动相,采用ESI正离子源并在多反应监测(MRM)模式下测定,通过比较分子离子峰、二级碎片离子峰、色谱保留时间等信息确定添加的化学药物,并根据外标法以质谱峰面积计算添加药物的准确量。结果 12种化学药物阿替洛尔、可乐定、氢氯噻嗪、卡托普利、哌唑嗪、利血平、硝苯地平、氨氯地平、尼群地平、尼莫地平、尼索地平、非洛地平分离度良好,在1 ng/ml～500 ng/ml质量浓度内具有良好的线性关系(r≥0. 998 0),方法检出限(LOD)为0. 005 ng/g～0. 52 ng/g,定量限(LOQ)为0. 021 ng/g～1. 63 ng/g,回收率为83. 2%～117. 3%,相对标准偏差为0. 8%～6. 7%。结论 本法简便、准确、灵敏度高,可作为降压类中成药及调节血压类保健食品中非法添加化学降压药的快速检验方法。     

工作场所空气中邻苯二甲酸酐测定方法的研究

空气中邻苯二甲酸酐用玻璃纤维滤纸采集,随即放入预先装有2 ml丙酮的样品瓶中,盖塞,摇匀后用DB-1毛细管柱气相色谱(FID)测定。邻苯二甲酸酐浓度在0~200μg/ml范围内线性关系良好,线性方程y=8.9+12.6x(r=0.999 9。检出限为0.39μg/ml,若采集30 L空气样品,则最低检出浓度分别为0.026 mg/m3,平均加标回收率99.7%~101.4%,相对标准偏差在1.2%~3.7%。本方法适用于工作场所空气中邻苯二甲酸酐浓度的测定。     

保健食品中辅酶Q10含量的测定及其提取条件的研究

目的:本文建立了测定保健食品中辅酶Q10的高效液相色谱法,并对不同溶剂对辅酶Q10提取效果的影响进行了研究.方法:样品在40℃下,乙酸乙脂超声提取15 min,采用Symmetry C18 4.6×250 mm柱分离;流动相为甲醇 乙醇(30 70),样品盘和色谱柱温度均为35℃,流速为1.5 ml/min,检测波长275 nm.结果:在10～600μg/ml范围内,峰面积与质量浓度成良好的线性关系(r2=0.999),RSD为0.6%,最低检出限0.8 ng.样品中辅酶Q10的提取率>96%,RSD为2.83%.结论:该方法快速、准确,提取效率高,适用于保健食品中辅酶Q10含量的测定.     

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.