北京市空气污染物对呼吸系统疾病门诊人数的影响

为评价北京市大气污染对居民呼吸系统疾病门诊人数的影响,采用时间序列半参广义相加模型(GAM),在控制了长期趋势、“星期几效应”及气象因素的影响后,分析2009~2011年北京市空气污染物与呼吸系统疾病门诊人数的暴露-反应关系,并按性别和年龄层建立模型.结果表明,3种污染物有一定的滞后效应,PM10在滞后0~3d(avg03)或0~5d(avg05)的移动平均值,SO2和NO2均在滞后0~2d(avg02)的移动平均值使呼吸系统疾病门诊人数的增加百分比(PI%)值达到最大,其中PM10、SO2和NO2浓度每增加10μg/m3,对应的呼吸系统疾病全人群的PI%分别为1.72%、1.34%和2.57%.年龄365岁的老年人群对北京市空气污染物最为敏感,其次为年龄￡14岁的人群;空气污染对女性的影响较男性明显.     

Adult respiratory distress syndrome in human organophosphate poisoning cases

Adult respiratory distress syndrome (ARDS) is a clinical syndrome which occurs due to various direct or indirect noxious agents and pyhsical mechanisms. One of the etiological factors is ingested chemicals (e.g. paraquat, ethylene glycol). The organophosphorous (OP) insecticides are the most toxic and frequently encountered chemicals that produce poisoning in humans. Studies were undertaken to investigate whether OP insecticides may produce ARDS. Fifteen autopsy cases due to suicidal OP insecticide poisoning were investigated. Toxicological analyses were performed with a gas chromatography-nitrogen phosphorous detector (GC-NPD). Methamidophos, dimefox and dichlorvos were the detected OP. Lungs were examined macroscopically. Two cases showed features compatible with ARDS in which the only cause of death was OP poisoning. Due to the severity of ARDS it is important to assess insecticidal exposure in an attempt to enhance survival patterns following OP poisoning in patients in order to initiate therapy.     

Arsenic species in the well water and sediments of the blackfoot disease area in Taiwan

The blackfoot disease (BFD) observed in southwestern Taiwan is due to drinking high arsenic concentrations in well water. This paper presents some results concerning the distributions of arsenic species in water and sediments collected in the BFD (well, river and coastal) area and the background (lake and ocean) area for comparison. The results show that the concentrations of arsenate (870 ± 26 ug/L) and arsenite (70.2 ± 2.6 ug/ L) in well waters, and the contents of arsenic (1640 ug/g) with high percentage of easily reducible (Fe and Mn oxides, 91.7%) and exchangeable and carbonate (4.6%) phases in well sediments were much higher than those in river, lake and coastal samples. Low arsenic (3.46–31.8 ug/g) with high percentages (73.8–97.3%) of detritus and minerals phase with low percentages (0.4–9.8%) of total carbonate and exchangeable phases were found in the river and coastal samples in the BFD area as well as the lake and ocean samples in background area. It might suggest that the higher concentrations of toxic As(III) in well water and arsenic with higher values of easily reducible, carbonate and exchangeable phases in the well sediments, combined with the higher values of dissolved organic carbon, humic and fulvic acids and aromatic carbon as well as the higher fluorescence indensity in the well water are the key factors to cause the BFD in Taiwan.     

Reduced effect of Tasmanian devil facial tumor disease at the disease front

Pathogen-driven declines in animal populations are increasingly regarded as a major conservation issue. The Tasmanian devil (Sarcophilus harrisii) is threatened with extinction by devil facial tumor disease, a unique transmissible cancer. The disease is transmitted through direct transfer of tumor cells, which is possible because the genetic diversity of Tasmanian devils is low, particularly in the major histocompatibility complex genes of the immune system. The far northwest of Tasmania now holds the last remaining disease-free wild devil populations. The recent discovery of unique major histocompatibility complex genotypes in the northwestern region of Tasmania has raised the possibility that some animals may be resilient to the disease. We examined the differences in the epidemiology and population effects of devil facial tumor disease at 3 well-studied affected sites in eastern Tasmania and 1 in western Tasmania (West Pencil Pine). In contrast to the 3 eastern sites, there has been no rapid increase in disease prevalence or evidence of population decline at West Pencil Pine. Moreover, this is the only onsite at which the population age structure has remained unaltered 4 years after the first detection of disease. The most plausible explanations for the substantial differences in population effects and epidemiology of the disease between eastern and western sites are geographic differences in genotypes or phenotypes of devils and functional differences between tumor strains in the 2 regions. We suggest that conservation efforts focus on identifying whether either or both these explanations are correct and then, if resistance alleles exist, to attempt to spread the resistant alleles into affected populations. Such assisted selection has rarely been attempted for the management of wildlife diseases, but it may be widely applicable.     

北京不同污染天气PM_(2.5)和PM_(10)染毒对大鼠生理病理参数的影响

为探讨北京不同污染天气大气可吸入颗粒物PM_(10)和细颗粒物PM_(2.5)污染对雄性大鼠血常规、氧化损伤、炎症反应和肺组织的影响,将64只雄性8周龄Wistar大鼠随机分为8组,分别为2个对照组(空白组和生理盐水组)和6个染毒组(清洁、雾霾及沙尘暴3种不同天气的PM_(10)染毒组和PM_(2.5)染毒组),每组8只。用2015年3月—5月在北京南海子麋鹿苑采集的清洁、雾霾和沙尘暴3种不同天气的PM_(10)和PM_(2.5)制备悬液,分别采用气管滴入PM_(10)和PM_(2.5)悬液作为染毒组,空白对照组不做任何处理,生理盐水对照组采用气管滴注生理盐水。急性染毒24 h后处死大鼠。采集血液测定18个血常规指标,分析肺泡灌洗液(BALF)中转化生长因子-β1(TGF-β1)、乳酸脱氢酶(LDH)、总抗氧化能力(T-AOC)、白介素-6(IL-6)及肿瘤坏死因子-α(TNF-α)的含量,并在高倍显微镜下观察肺组织和气管病理形态变化。同时,对PM_(10)和PM_(2.5)中的水溶性离子、有机碳/元素碳、16种多环芳烃和7种重金属等元素进行了测定,并分析了各组分与大鼠生理病理指标的相关性。结果表明:清洁、沙尘暴天气的PM_(10)和雾霾天气的PM_(2.5)急性染毒导致大鼠白细胞系参数即免疫力显著下降。污染天气颗粒物染毒后大鼠BALF氧化炎症因子的改变表明呼吸系统受到感染:沙尘暴和清洁天的PM_(10)染毒均显著提高了TGF-β1,雾霾PM_(10)染毒后IL-6和LDH有一定程度升高。3种天气颗粒物染毒对肺和气管造成的组织病理伤害各有特点,但PM_(2.5)伤害程度普遍大于PM_(10)。染毒颗粒物粒径大小,其化学成分类别、浓度是造成大鼠血常规指标变化、氧化炎症反应和组织学病变的可能原因。     

邻苯二甲酸二丁酯影响阿尔茨海默病大鼠学习记忆能力的分子机制研究

为探究邻苯二甲酸二丁酯（DBP）影响阿尔茨海默病（AD）大鼠学习记忆能力的分子机制,将56只SPF级5~6周龄雌性Wistar大鼠随机平均分为7组：阴性对照组、0.25 mg·kg^-1·d^-1 DBP组、2.5 mg·kg^-1·d^-1 DBP组、25 mg·kg^-1·d^-1 DBP组、250 mg·kg^-1·d^-1 DBP组、AD模型组和AD+25 mg·kg^-1·d^-1 DBP组.连续灌胃处理28 d,观察Morris水迷宫结果,检测脑海马组织中活性氧（ROS）、还原型谷胱甘肽（GSH）、丙二醛（MDA）、8-羟基脱氧鸟苷（8-OHdG）的含量;采用实时荧光定量PCR （qPCR）检测Bcl-2、Bax和Caspase-3 mRNA的转录水平;通过免疫印迹试验（Western blot）检测Bcl-2、Bax和Caspase-3的蛋白表达水平.结果表明,与阴性对照组相比,不同染毒组、DBP组大鼠的学习记忆能力下降,氧化应激水平上升,且随DBP染毒浓度升高而加剧（p<0.05,p<0.01）;AD+25 mg·kg^-1·d^-1 DBP组较AD模型组大鼠的学习记忆能力损伤加剧,氧化应激水平和Bcl-2/Bax/Caspase-3信号通路上调,差异具有统计学意义（p<0.05）.由此推测,DBP可通过氧化应激作用,上调Bcl-2/Bax/Caspase-3信号通路,加剧AD大鼠海马组织的损伤,导致学习记忆能力下降.本文通过DBP影响AD大鼠学习记忆能力的分子机制研究,揭示了氧化应激对凋亡信号通路的作用,并为进一步研究DBP的毒性提供了理论和数据依据.     

Estimating the spatio-temporal risk of disease epidemics using a bioclimatic niche model

There are presently few tools available for estimating epidemic risks from forest pathogens, and hence informing pro-active disease management. In this study we demonstrated that a bioclimatic niche model can be used to examine questions of epidemic risk in temperate eucalypt plantations. The bioclimatic niche model, CLIMEX, was used to identify regional variation in climate suitability for Mycosphaerella leaf disease (MLD), a major cause of foliage damage in temperate eucalypt plantations around the world. Using historical observations of MLD damage, we were able to convert the relative score of climatic suitability generated by CLIMEX into a severity ranking ranging from low to high, providing for the first time a direct link between risk and impact, and allowing us to explore disease severity in a way meaningful to forest managers. We determined that the ‘Compare Years’ function in CLIMEX could be used for site-specific risk assessment to identify severity, frequency and seasonality of MLD epidemics. We explored appropriate scales of risk assessment for forest managers. Applying the CLIMEX model of MLD using a 0.25° or coarser grid size to areas of sharp topographic relief frequently misrepresented the risk posed by MLD, because considerable variation occurred between individual forest sites encompassed within a single grid cell. This highlighted the need for site-specific risk assessment to address many questions pertinent to managing risk in plantations.     

木麻黄根区土壤理化特性及酶活性与青枯病发生关联分析

为探究木麻黄(Casuarina spp.)根区土壤理化特性及酶活性与青枯病发生的关系,进而为加强生物防治提供参考.选取位于广东省潮州市饶平县大埕镇、湛江市吴川市塘尾镇和湛江市徐闻县前山镇的3个木麻黄人工林为研究对象,在每个林分下分别设置3个样地,每个样地采集木麻黄青枯病感病植株和健康植株根区土壤各3份,共54个土壤样...     

Analysis of Total Work Inability in Poland in 2000 and 2001 According to Age,Disease Diagnosis and Occupation

This study was to determine the main health-related reasons, age and occupation of those who took ear retirement due to total work inability. This was done through an analysis of the data from Poland’s Soci Insurance Institution (ZUS) from 2000 and 2001. An analysis of these data showed an increase in the numb of certificates confirming total inability to work in people over 40 years old. Over 50% of certificates wo, were issued to workers in 2 age-groups: 45–49 and 50–54.

Diseases of the circulatory system, musculoskeletal system and connective tissue as well as mental and behavioural disorders are the main causes of early inability to work. Approximately 70% of people who obtained certificates confirming total inability to work had blue- and blue-and-white-collar jobs.     

Investigation of Blended Fibre Filtering Materials

Five variants of mixtures of different synthetic fibres at different area ratios were manufactured into needled nonwovens intended to be used as a filtering material for respiratory protection. Two variants were produced according to an earlier patent, and the contents of the other three was completely new. Samples of the nonwovens were tested for sodium chloride particles penetration and for breathing resistance. The results showed that one variant of a nonwoven, designated PP/PPFM, had very valuable filtering properties and that those properties were stable in time.