去蛋氨酸/缬氨酸空肠喂饲荷瘤大鼠对其体内分布及核酸、蛋白质代谢的影响

观察去蛋氨酸 /缬氨酸空肠喂饲荷瘤大鼠对其体内分布及核酸、蛋白质代谢的影响。 SD大鼠空肠造瘘 ,皮下接种Walker- 2 5 6癌肉瘤 ,分 A、B、C、D4组。分别以平衡氨基酸、去蛋氨酸、平衡氨基酸、去缬氨酸空肠喂养 6天 ,注入 3H -蛋氨酸 /缬氨酸 (3H- Met/ Val) 7.4× 10 5 Bq,0 .5、1、2、4h后分别测定肿瘤组织 RNA、DNA及蛋白质的 H掺入率 ,测定各时点肝、胰、小肠、肌肉、血浆及肿瘤组织的放射性强度 ,计算差示摄取比 (DU R)。结果 :1B组肿瘤组织对 3H- Met摄取率2、4h分别为 (8.0 9± 0 .12 ) %及 (7.81± 0 .17) % ,高于 A组…     

3H-蛋氨酸/3H-缬氨酸空肠喂饲在荷瘤大鼠体内的分布

目的观察3H-蛋氨酸/3H-缬氨酸空肠喂饲在荷瘤大鼠体内的分布.方法SD大鼠空肠营养性造瘘,皮F接种Walker-256癌肉瘤,分为A、B、C、D组,分别以含平衡氨基酸、去蛋氨酸、平衡氨基酸及去缬氨酸的肠外营养空肠喂饲6天,再注入3H-蛋氨酸(A、B组)或3H-缬氨酸(C、D组)7.4×105 Bq,于0.5、1、2和4小时测肝、胰、小肠、肌肉、血浆及肿瘤组织的cpm,计算差示摄取率(DUR).结果A组及B组肿瘤组织DUR值仅低于胰腺组织(P＜0.01);B组血浆DUR值低于A组(P＜0.01).D组肿瘤组织DUR值高于C组(P＜0.01);D组血浆DUR值低于C组(P＜0.01).结论3H-蛋氨酸/3H-缬氨酸在肿瘤组织摄取率高;蛋氨酸、缬氨酸是肿瘤组织代谢的重要基质.     

局部振动对家兔血浆内皮素浓度的影响

目的　探讨局部振动对血浆内皮素浓度的影响及其与振动性血管损伤之间的关系。方法　将家兔随机分为A组 (接振强度 4.90m/s2 )、B组 (接振强度 15 .31m/s2 )、C组 (接振强度 2 6 .2 6m/s2 )和 1个对照组 ,分别于不同接振时间测定各组家兔血浆内皮素浓度。结果　接振后 10、2 0、30d ,A组的血浆内皮素浓度分别为 (4 5 .71± 3.6 2 )pg/ml、(5 1.97± 4.46 )pg/ml、(5 5 .37± 5 .5 3)pg/ml;B组分别为 (5 2 .5 6± 8.0 0 )pg/ml、(6 3.2 4± 6 .73)pg/ml、(72 .98± 9.2 4)pg/ml;C组分别为 (6 4.77± 5 .0 8)pg/ml、(83.6 4± 9.36 )pg/ml、(82 .5 6± 6 .41)pg/ml。随接振时间的延长和接振剂量的增大 ,血浆内皮素浓度有升高的趋势 ,振动试验后 ,各试验组血浆内皮素浓度均高于对照组 ,差异有显著性 (P <0 .0 5 ,P <0 .0 1)。结论　局部振动可致家兔血浆内皮素浓度增高 ,这种增高与振动性血管损伤有一定联系     

对氧磷酶1 55 Met/Leu、对氧磷酶2 148 Ala/Gly和锰超氧化物歧化酶9 Ala/Val基因多态性与冠心病

目的 探讨对氧磷酶155 Met/Leu(PON1 55 Met/Leu)、对氧磷酶2148 Ala/Gly(PON2148 Ala/Gly)和锰超氧化物歧化酶9 Ala/Val(MnSOD 9 Ala/Val)基因多态性与冠心病(CHD)、血浆对氧磷酶(PON)、总超氧化物歧化酶(T-SOD)和锰超氧化物歧化酶(MnSOD)活性以及丙二醛(MDA)浓度的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法检测262例CHD患者和100名对照组的PON1 55 Met/Leu、PON2 148 Ala/Gly和MnSOD 9 Ala/Val基因多态性的基因型,采用比色法测定血浆PON、T-SOD和MnSOD活性以及MDA浓度.结果 与对照组比较,CHD患者的血浆PON[(349.27±138.36 vs 454.75±166.00)nmol·min-1·ml-1,P＜0.001]、T-SOD[(23.61±16.51 vs.44.01±22.68)U/ml,P＜0.001]和MnSOD活性[(21.56±13.11 vs.28.79±8.65)U/ml,P＜0.001]明显降低,MDA浓度显著增高[(2.47±0.73 vs.2.15±0.55)nmol/ml,P＜0.01];CHD患者的PON1 55 LM杂合子基因型、M等位基因频率,PON2 148 GG纯合子基因型和AG杂合子基因型、G等位基因频率和MnSOD 9 AA基因型、A等位基因频率较对照组明显增多;PON1 55 LM杂合子基因型的PON和T-SOD活性较LL纯合子基因型明显降低;PON2 148GG基因型和AG基因型的PON活性较AA基因型明显降低;MnSOD AA基因型的PON和MnSOD活性较VV基因型明显降低;logistic回归分析显示PON1 55 LM杂合子基因型、M等位基因、PON2148 GG/AG基因型、G等位基因是CHD的危险因子.结论 CHD患者的抗氧化能力明显降低,脂质过氧化物显著增高;PON1 55 Met/Leu、PON2 148 Ala/Gly和MnSOD 9 Ala/Val基因多态性通过影响血浆PON和MnSOD活性而参与CHD的发病.     

川芎嗪对失血性休克再灌注肺损伤IκB激酶-β表达的调节干预研究

目的　探讨IκB激酶 -β(IKK -β)在失血性休克继发急性肺损伤中的意义及川芎嗪 (Ligustrazini ,Lig)的调节干预作用。方法　采用原位杂交、免疫组织化学结合原位定量分析以及酶联免疫吸附试验分别检测模型组、川芎嗪组、对照组肺组织IKK -β、核因子 (NF) -κB表达以及血浆肿瘤坏死因子 -α(TNF -α)含量 ,并行病理学光镜检查。结果　模型组上述指标依次为 [(0 2 2 3±0 0 80 )、(0 162± 0 0 2 1)、(80 9 3 3± 2 0 1 6)ng/L] ,较对照组升高 (P <0 0 5 ) ,肺组织有明显炎症改变 ,川芎嗪组上述指标依次为[(0 163± 0 0 66)、(0 12 0± 0 0 2 0 )、(4 4 7 5 0± 10 0 80 )ng/L] ,较模型组降低 (P <0 0 5 ) ,肺组织炎症改变减轻。结论　IKK -β/NF -κB/TNF -α效应是失血性休克继发急性肺损伤的重要机制 ;川芎嗪可下调IKK -β/NF -κB通路减轻失血性休克后的急性肺损伤。     

老年周围动脉硬化闭塞病与血浆纤维蛋白原、血小板集聚率关系的研究

目的　探讨血浆纤维蛋白原、血小板聚集对老年周围动脉硬化闭塞病 (PAOD)的影响。方法　在北京市万寿路地区 2 0 4 11名老年居民中 ,以家委会为单位整群随机抽样 2 12 1人 ,男 94 1人 ,女 1180人 ,最大年龄 89岁 ,最小年龄 6 0岁 ,平均年龄 6 8.5 1岁± 4 .83岁。以踝动脉指数 <0 .9为PAOD诊断标准。以此诊断分成PAOD与非PAOD人群。在PAOD人群中抽取病例组 2 32例 ,其中男 73例、女 15 9例 ,平均年龄 70 .97岁± 6 .4 6岁 ;在非PAOD人群中按完全随机方式抽取对照组 4 6 4人 ,其中男 2 17人、女 2 4 7人 ,平均年龄 6 8.6 3岁± 5 .2 9岁。病例组与对照组均化验血浆纤维蛋白原浓度 ,血小板最大聚集率及 3min血小板聚集率。同时在两组中对PAOD患病有影响的因素进行多元logistic逐步回归分析。 结果　PAOD病例组血浆纤维蛋白原 (435 .4 5mg/dl±115 .2 5mg/dl)高于对照组 (36 0 .96mg/dl±93.5 2mg/dl) ,P =0 .0 0 1;3min血小板聚集率 (48.76 %± 2 3.90 % )高于对照组(43.5 0 %± 2 6 .76 % ) ,P =0 .0 12。logistic回归结果也显示血浆纤维蛋白原 (OR =0 .994 ,95 %CI :0 .992～ 0 .994 )及 3min血小板聚集率 (OR =0 .5 78,95 %CI:0 .4 0 3～ 0 .82 9)为对PAOD患病有显著影响意义的因素。结论　PAOD患者中     

小肠减压、肠外营养支持、生长抑素联合应用治疗单纯性肠梗阻

探讨联合应用导管小肠减压、肠外营养支持、生长抑素治疗单纯性肠梗阻的效果。将 6 4例肠梗阻病人随机分为三组 ,分别予以小肠减压 (A组 ) ,小肠减压 +营养支持 (B组 ) ,小肠减压 +营养支持 +生长抑素 (C组 ) ,治疗时间为 7～ 14天 ,并定期评定其腹痛消失、肛门排气、气液平面消失和梗阻解除时间 ,小肠减压导管引流量和病人血浆前白蛋白亚油酸和氮平衡等营养状况。结果 :3组病人梗阻解除率为 85 .0 %、85 .7%、91.3% ,第 15天 B、C两组前白蛋白值为 30 1.32±72 .5 8、32 8.39± 6 4.19,亚油酸值为 6 6 .72± 2 0 .5 4、5 8.88±2 4.6 3,…     

二甲基甲酰胺对大鼠肾脏线粒体和微粒体~(45)Ca转运的影响

目的　研究二甲基甲酰胺 (DMF)对大鼠肾脏线粒体和微粒体4 5Ca转运的影响 ,探讨其肾脏损害的作用机制。方法　采用超速冷冻离心技术分离大鼠肾脏线粒体及微粒体 ,应用放射性同位素技术测定DMF对线粒体和微粒体4 5Ca主动摄取及释放的影响。结果　 (1) 45Ca的摄取 :孵育 10min时 ,DMF 130、195 μmol/L组大鼠肾线粒体4 5Ca摄取量分别为 (4 .2 0± 0 .2 9)、(3.81± 0 .42 )nmol/mgpro,对照组为(5 .18± 0 .40 )nmol/mgpro;微粒体4 5Ca摄取量分别为 (2 .10± 0 .42 )、(2 .0 1± 0 .38)nmol/mgpro ,对照组为(2 .96± 0 .38)nmol/mgpro。DMF两个剂量组与对照组的差异均有显著性 (P <0 .0 5或P <0 .0 1)。 (2 ) 45Ca的释放 :孵育 2min时 ,DMF 6 5、130、195 μmol/L组大鼠肾线粒体4 5Ca残留量分别为 (5 .40± 0 .39)、(5 .0 3±0 .32 )、(4 .70± 0 .5 0 )nmol/mgpro,对照组为 (6 .0 1± 0 .40 )nmol/mgpro ;微粒体4 5Ca残留量分别为 (3.43±0 .2 6 )、(3.18± 0 .31)、(3.0 6± 0 .2 7)nmol/mgpro ,对照组为 (4 .0 6± 0 .32 )nmol/mgpro。DMF两个剂量组与对照组的差异均有显著性 (P <0 .0 1)。(3)DMF与鼠肾线粒体和微粒体4 5Ca的摄取、释放均存在剂量 -效应关系 (前者 :r=0 .918,r=0 .895 ;后者 :r=0 .886     

0.4 mT工频磁场对骨骼肌肌质网囊泡游离钙离子转运的影响

目的探讨工频磁场对骨骼肌肌质网钙转运动力学的影响.方法利用动态光谱法检测0.4 mT、50 Hz正弦磁场辐照过的骨骼肌肌质网Ca2+转运和钙泵活性,用3H-兰尼碱结合实验检测Ca2+释放通道的活性,用荧光偏振法检测肌质网膜的流动性等.结果 0.4 mT、50 Hz正弦磁场辐照导致提取的肌质网囊泡Ca2+摄取初速率由每秒(29.18±3.90) pmol/mg下降到(24.60±3.81) pmol/mg,钙泵的活性由每分钟(0.93±0.05) μmol/mg下降到(0.69±0.07) μmol/mg;导致Ca2+释放初速率由每秒(4.83±0.82) pmol/mg上升到(5.65±0.43) pmol/mg,3H-兰尼碱结合度由(1.10±0.12) pmol/mg上升到(1.16±0.13) pmol/mg,分别上升了15%和5%.结论 0.4 mT工频磁场辐照引起的肌质网Ca2+摄取下调和Ca2+释放上调是由于肌质网钙泵活性降低和Ca2+释放通道活性升高所致.     

醋酸铅对大鼠脑细胞凋亡及bcl-2基因表达的影响

目的　探讨醋酸铅 (PbAc)对大鼠脑细胞凋亡的诱发作用及对bcl 2基因表达的影响。方法　SD大鼠腹腔分别注射PbAc 2 5、5 0、10 0mg/kg 5d ,第 6天用流式细胞仪分别测定其大脑皮层、海马和小脑组织的细胞凋亡率和bcl 2基因的表达产物Bcl 2蛋白含量。结果　染铅大鼠大脑皮层、海马、小脑细胞凋亡率 (% ) :2 5mg/kgPbAc组为 5 .80± 0 .87、4.82± 0 .37、4.82± 1.2 3 ,5 0 mg/kg组值高于 2 5mg/kg组 ,10 0mg/kg组值高于 5 0mg/kg组 ,均比对照组 (1.40± 0 .70、2 .0 0± 0 .6 3、1.6 6±0 .49)高 ,差异有显著性 (P <0 .0 1) ;并有剂量 -反应关系 (r值分别为 0 .998、0 .989、0 .997)。染铅大鼠大脑皮层、海马、小脑bcl 2基因表达 (FI指数 ) :2 5mg/kgPbAc组为 0 .6 8± 0 .0 3、0 .6 1± 0 .0 6、0 .6 9± 0 .0 5 ;5 0mg/kg、10 0mg/kg组值均与 2 5mg/kg组接近 ,但均比对照组 (1.0 0± 0 .13、1.0 0±0 .17、1.0 0± 0 .13)降低 ,差异有显著性 (P <0 .0 1) ;并有剂量 -反应关系 (r值分别为 0 .886、0 .787、0 .832 )。大鼠大脑皮层、海马和小脑细胞凋亡率与Bcl 2含量呈负相关 (r值分别为 - 0 .75 0、- 0 .5 0 9、- 0 .6 6 7)。结论　铅可以诱发大鼠脑细胞凋亡 ,其机制可能与脑组织内bcl 2基因表达下调有关     

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.     

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.