神经毒物生化效应标志物在职业医学中的应用

许多化学物具有神经毒性作用,通过检测神经毒性效应标志物可望早期有效防治中毒性神经系统疾病。本文就神经毒物生化效应标志物在职业卫生和职业医学中的应用及前景作一综述。     

毒理学研究与中毒急救

１毒性与毒理学研究化学物毒性（Ｔｏｘｉｃｉｔｙ）是化学物内在固有的特性,是指引起机体损害的能力。衡量毒性的大小可以是指测量该化学物引起实验动物某种毒效应所需的剂量或浓度,通常可用剂量－反应（效应）关系表示。引起某种效应所需的化学物剂量越小,则表明该化学物毒性越大。研究化学物的毒性和毒作用机理是毒理学的重要任务,涉及毒物在体内过程、对机体的各种可能效应与机制、效应修饰因素、作用阈限等诸多内容。不同毒物的毒性、靶器官及毒作用方式相差较大。通过常规毒性研究,可以提供与之有关的资料,这在安全性评价过程中…     

铅的生物标志物研究进展

生物标志物通常分为反映接触水平的接触标志物 ,反映化学物或其他代谢物早期生物学效应、机体结构或者功能改变和疾病的效应标志物和反映个体易感性的易感标志物 3大类。对于毒物对机体健康损害的早期发现、早期阻断起着重要的作用。现就铅的生物标志物研究进展综述如下。1　接触标志物1 1　血铅 (Pb -B)　血铅 ,主要是红细胞铅 ,是软组织铅的代表 ,是反映近期铅接触的敏感指标 ,与其他指标相关性较好 ,所以被较广泛地用作为铅吸收或铅负荷的指标 ,在评价其他指标时也常以血铅为准。但由于各国工业化程度不同经济状况、种族、生活习惯等不…     

国内职业医学生物监测现况

职业医学领域的监测包括环境监测(Ambient Monitoring, AM)、生物监测(Biological Monitoring, BM)和健康监护(Surveillance Health ,SH).随着生物监测技术的不断完善,其在职业有害因素评价体系中的地位日益加强,改变了长期以来均认为"环境监测为主、生物监测为辅"的观念,它与环境监测"相辅相成、互为补充"的观点正成为学术界共识.生物标志物是生物监测的重要研究对象,近几年伴随着分子生物标志物的发展,生物监测技术提高到了分子水平.生物标志物一般分为3类:①接触生物标志物:是指测定机体器官或组织内的外源性化学物及其代谢产物或外源性化学物与靶分子、靶细胞相互作用的产物,以反映内剂量和生物效应剂量;②效应生物标志物,指机体中可测出的生化、生理、行为或其他改变的指标,以及早期生物效应、结构和/或功能改变、疾病等;判断机体是否受到明确的或潜在的危害;③易感性生物标志物,指能反映机体先天遗传性或后天获得性的对外源性化合物接触产生反应能力大小的指标.     

外源性化学物致机体DNA损伤与修复的生物标志物研究进展

机体在面临外源性化学物威胁时，仍能维持遗传信息的完整性和稳定性的重要机制是DNA修复。外源性化学物暴露造成的细胞基因组不稳定性增高，是化学物暴露、机体代谢及DNA修复等相关机制共同作用的结果，也是肿瘤发生和发展的重要原因和表现。已有证据表明，DNA修复能力降低与正常人群散发肿瘤的危险性增高显著关联。正常人群的个体间DNA修复能力存在较大变异。因此，研究个体间DNA修复能力差异的遗传学基础，对于加深外源性化学物致癌机理的认识、发展生物标志物以及最终提高肿瘤危险度评价的精度有重要意义。我们在扼要介绍DNA损伤与修复机制的基础上，重点介绍外源性化学物致机体DNA损伤和修复的生物标志物研究进展。     

二甲苯与其它化学物联合作用的生物学效应

二甲苯与其它化学物联合作用的生物学效应王秀玲金锡鹏综述刚葆琪审校在工业生产中，二甲苯常与其它化学物混合使用，当它们同时进入机体时，在吸收、代谢以及排泄等方面可能互相影响，以致毒效应有所改变。因此，了解二甲苯与其它化学物联合作用的生物学效应，就有着十分...     

接苯人群生物标志物研究进展

生物标志物可以分为四大类：内剂量、生物有效量（ＤＮＡ、ＲＮＡ和蛋白质加合物）、早期生物效应和个体易感性标志物。其中内剂量及生物有效量标志物都可作为接触标志物。一、内剂量标志物所谓内剂量系指职业接触、环境接触化学物进入机体内的量。内剂量与外剂量、生物有效量及生物效应有直接关联。苯只有经代谢活化后才能行使其致毒、致癌作用,因此人体接触苯后,通过机体代谢作用生成苯的各种活性代谢产物便成为接触苯后不同的内剂量标志物,样品多来源于血液和尿液。最有希望的代谢产物是反式,反式粘糠酸（ｔｒａｎｓｔｒａｎｓｍ…     

生物标志物在职业医学中的应用

生物标志物在职业医学中的应用中国预防医学科学院劳动卫生与职业病研究所（１０００５０）黄金祥生物标志物在职业医学研究和实际应用中的作用近年来倍受重视，尤其是加合物的研究更是当前国际职业医学界热门的课题之一。生物标志物可反映人体接触化学物所致健康损害这一...     

接触化学物的危险度评定中作为毒性终点的生物标志物的应用

接触化学物的危险度评定中作为毒性终点的生物标志物的应用Ｍ．Ｊ．Ｍｅｒｃｉｅｒ，Ａ．Ｅ．Ｒｏｂｉｎｓｏｎ一、前言本文拟检查一些概念、原则和机会，如何通过适当选择和应用生物标志物以改进因接触化学物而危害人体健康的危险度评定过程。与化学物诱发毒性改变有关的...     

化学物毒理学资料在职业卫生中的作用

化学物毒理学特性向其理化特性一样，是化学物的基本属性之一。化学物毒理学资料的应用可以贯穿于职业中毒预防的各个层面中，如化学物的一般管理、劳动卫生调查研究、化学物现场检测、接毒人员的职业性健康监护与职业病诊断、中毒事件的应急救援、建设项目的卫生评价及评定化学物毒性、职业卫生科研、职业卫生标准的制定等。在职业卫生工作中，了解化学物的主要毒理学数据和毒作用特征，对其中毒预防管理必不可少，对中毒防治工作得以有成效开展起到重要的作用。文中还简单介绍了化学物毒性资料的获取方法，并对化学物的毒性鉴定与化学品安全性评价的意义作了简单探讨。     

医学装备的电磁辐射及其生物效应的探讨

将对各类医学装备的电磁辐射可能给医务人员及患者带来的身体损害进行定性分析,结合相关实验数据的分析,探讨与医学装备相关的各类电磁辐射可能产生的生物效应,并初步研究对应的防护措施,使医学装备在发挥其重要的临床救治作用的同时尽量减低电磁辐射对使用人员身体健康所产生的潜在危害。     

An objective Bayesian analysis of a crossover design via model selection and model averaging

Inference about the treatment effect in a crossover design has received much attention over time owing to the uncertainty in the existence of the carryover effect and its impact on the estimation of the treatment effect. Adding to this uncertainty is that the existence of the carryover effect and its size may depend on the presence of the treatment effect and its size. We consider estimation and testing hypothesis about the treatment effect in a two‐period crossover design, assuming normally distributed response variable, and use an objective Bayesian approach to test the hypothesis about the treatment effect and to estimate its size when it exists while accounting for the uncertainty about the presence of the carryover effect as well as the treatment and period effects. We evaluate and compare the performance of the proposed approach with a standard frequentist approach using simulated data, and real data. Copyright © 2016 John Wiley & Sons, Ltd.     

Education and income effects in the use of ambulatory services in the United States: an analysis of the 1970 National Health Interview Survey data

The roles of education and income as determinants for utilization of ambulatory services in the U.S. are investigated by the application of path analysis to a subsample of the 1970 National Health Interview Survey. The methodology permits the identification of both the direct and indirect effects of each independent variable on utilization within a model that views need as the major determinant of care. Previous findings that income has no direct effect on utilization, while education does, are reaffirmed. Contrary to previous analyses, however, it is shown that income does have a strong indirect effect on utilization via its impact on need arising from chronic conditions, measured as limitation of activity. Individuals in the highest income category have a mean annual visit rate of 4.13, while the rate for those in the lowest is 5.43. Most of the differential, 1.3, is attributable to the lower prevalence of chronic conditions in the highest income bracket. The total effect of education, on the other hand, is only 60% of its direct effect since higher educational attainment is associated with lower levels of chronicity. Disaggregation of direct and indirect effects through the need variables shows that income has a greater effect on utilization than does education.     

Caffeine during High-Intensity Whole-Body Exercise: An Integrative Approach beyond the Central Nervous System

Caffeine is one of the most consumed ergogenic aids around the world. Many studies support the ergogenic effect of caffeine over a large spectrum of exercise types. While the stimulatory effect of caffeine on the central nervous system is the well-accepted mechanism explaining improvements in exercise performance during high-intensity whole-body exercise, in which other physiological systems such as pulmonary, cardiovascular, and muscular systems are maximally activated, a direct effect of caffeine on such systems cannot be ignored. A better understanding of the effects of caffeine on multiple physiological systems during high-intensity whole-body exercise might help to expand its use in different sporting contexts (e.g., competitions in different environments, such as altitude) or even assist the treatment of some diseases (e.g., chronic obstructive pulmonary disease). In the present narrative review, we explore the potential effects of caffeine on the pulmonary, cardiovascular, and muscular systems, and describe how such alterations may interact and thus contribute to the ergogenic effects of caffeine during high-intensity whole-body exercise. This integrative approach provides insights regarding how caffeine influences endurance performance and may drive further studies exploring its mechanisms of action in a broader perspective.     

Flavor components of monoterpenes in citrus essential oils enhance the release of monoamines from rat brain slices

Citrus essential oils have been utilized widely in traditional medicine, and there are various reports of actions such as effects on behavior and effects on pain stimulation response due to exposure. However, there are no reports concerning effects on neurotransmitters after ingestion, and uptake within the brain. We used brain tissue slices to investigate the effect of compounds in lemon essential oil on monoamine release. We investigated R-limonene, gamma-terpinene and citral, major components of lemon essential oil; S-limonene, an isomer of R-limonene and metabolites of these compounds. The effect of each compound on monoamine release from brain tissue slices was found to be dose-dependent. R-Limonene and its S-isomer demonstrated differences with regard to monoamine release from brain tissue. S-Limonene and its metabolites were found to have a stronger effect than the R-isomer. Limonene metabolites taken up in vivo were also found to have a stronger effect on monoamine release than both the R-form and the S-form. In an investigation of dopamine release using stratum slices, terpinene and pinene demonstrated no clear differences in activity attributable to isomers. However, rho-cymene, a gamma-terpinene metabolite, was found to have a stronger effect than gamma-terpinene. These results suggest that the metabolites of these monoterpene compounds contained in citrus essential oils have a stronger effect on monoamine release from brain tissue than the monoterpene compounds themselves.     

Stimulatory effect of apigenin-6-C-β-l-fucopyranoside on insulin secretion and glycogen synthesis

In vivo and in vitro treatments were carried out to investigate the effects of apigenin-6-C-β-l-fucopyranoside (1), isolated from Averrhoa carambola L. (Oxalidaceae), on serum glucose and insulin levels in hyperglycemic rats as well as its effect on glycogen synthesis in normal rat soleus muscle. Apigenin-6-C-β-l-fucopyranoside showed an acute effect on blood glucose lowering in hyperglycemic rats and stimulated glucose-induced insulin secretion. A stimulatory effect of 1 on glycogen synthesis was observed when muscles were incubated with this flavonoid and also its effect was completely nullified by pre-treatment with insulin signal transduction inhibitors. Taking this into account, the MAPK–PP1 and PI3K–GSK3 pathways are involved in the apigenin-6-C-β-l-fucopyranoside-induced increase in glycogen synthesis in muscle. This study provides evidence for dual effects of apigenin-6-C-β-l-fucopyranoside as an antihyperglycemic (insulin secretion) as well as an insulinomimetic (glycogen synthesis) agent.     

铝的毒性作用研究进展

目的 了解铝对人体各系统的影响,为控制其毒性作用提供一定参考依据。方法 检索PubMed数据库,纵览国外关于铝暴露致体内、体外危害及相关机制的文献,进一步选择如亚慢性铝暴露60天对小鼠唾液腺的影响等文献,提炼其相关结果结论进行综述。结果 铝摄入剂量和暴露时间可能对各系统有消极作用,对神经系统的作用尤为明显。结论 铝对人体各系统均有毒性作用,可能是各系统相关疾病发生因素之一,尤其是导致阿尔兹海默病等神经退行性疾病发生的重要原因之一。     

Flavor components of monoterpenes in citrus essential oils enhance the release of monoamines from rat brain slices

Abstract

Citrus essential oils have been utilized widely in traditional medicine, and there are various reports of actions such as effects on behavior and effects on pain stimulation response due to exposure. However, there are no reports concerning effects on neurotransmitters after ingestion, and uptake within the brain. We used brain tissue slices to investigate the effect of compounds in lemon essential oil on monoamine release. We investigated R-limonene, γ-terpinene and citral, major components of lemon essential oil; S-limonene, an isomer of R-limonene and metabolites of these compounds. The effect of each compound on monoamine release from brain tissue slices was found to be dose-dependent. R-Limonene and its S-isomer demonstrated differences with regard to monoamine release from brain tissue. S-Limonene and its metabolites were found to have a stronger effect than the R-isomer. Limonene metabolites taken up in vivo were also found to have a stronger effect on monoamine release than both the R-form and the S-form. In an investigation of dopamine release using stratum slices, terpinene and pinene demonstrated no clear differences in activity attributable to isomers. However, ρ-cymene, a γ-terpinene metabolite, was found to have a stronger effect than γ-terpinene. These results suggest that the metabolites of these monoterpene compounds contained in citrus essential oils have a stronger effect on monoamine release from brain tissue than the monoterpene compounds themselves.     

Spillover effect of Japanese long-term care insurance as an employment promotion policy for family caregivers

We evaluate a spillover effect of the Japanese public long-term care insurance (LTCI) as a policy to stimulate family caregivers’ labor force participation. Using nationally representative data from 1995 to 2013, we apply difference-in-difference propensity score matching to investigate the spillover effect in two periods: before and after the introduction of the LTCI in 2000 and before and after its major amendment in 2006. Our results show that the LTCI introduction has significant and positive spillover effects on family caregivers’ labor force participation and the effects vary by gender and age. In contrast, the LTCI amendment is found to have generally negative spillover effects on their labor force participation. We draw attention to these spillover effects, as expanding labor market supply to sustain the economy would be a priority for Japan and other rapidly aging countries in the coming decades.     

Estimation of genetic model parameters: variables correlated with a quantitative phenotype exhibiting major locus inheritance

A major locus that is detected through its effect on one phenotype (a primary trait) may also affect other quantitative phenotypes or qualitative disease endpoints (secondary traits). The pattern of effects of the major locus on a set of primary and secondary traits suggests candidate defects for the mutant allele. The effects are directly estimable when "measured genotypes" or a tightly linked marker allow unambiguous assignment of major locus genotypes. When genotypes assignments are ambiguous for a major locus detected through its effect on a quantitative primary trait, we propose estimators using genotypic probabilities. Making certain reasonable assumptions, we demonstrate asymptotic unbiasedness of these genotypic probability estimators of the genotypic means and variances for either the quantitative primary or secondary traits, of the covariances between quantitative primary and secondary traits, and of prevalences for the secondary qualitative traits. An important application of genotypic probability estimators is to define an effect of a major locus that cannot be detected upon analysis of the variable; for example, major locus effects may be defined for hypertension or blood pressure as secondary traits, but not detected as primary traits.