Injury-related hospital admission of female firefighters in South Korea

Purpose. The main objective of this study was to ascertain whether injury-related hospital admission in all South Korea female firefighters is greater than that in the general population. Methods. To perform this comparison, the standardized admission ratios (SARs) and their 95% confidence intervals (CIs) were calculated by person-years and mortality computation software. Results. Compared to the general population, the SARs for overall injury (SAR?=?1.57, 95% CI [1.24, 1.96]) and for injury to the lower back (SAR?=?2.78, 95% CI [1.81, 4.07]) in the female firefighters were significantly higher. The SARs for injury to the knee (SAR?=?2.48, 95% CI [1.18, 4.55]) in emergency medical services (EMS) workers were significantly higher than those in the general population. Conclusions. Our study shows that the SARs of overall injury and injury to the lower back in female firefighters and knee injury in the EMS were significantly higher than those in the general population. Further studies are needed to protect the lower back of firefighters and the knees of EMS.     

Behavioural toxicity in zebrafish (Danio rerio) exposed to waterborne zinc and chromium(VI)

This study is to investigate the behavioural responses of zebrafish to the toxic effects of waterborne zinc and chromium(VI). Swimming performance of fish was tracked by a real-time toxicity bio-monitoring system and transformed into data to calculate individual and fish school behavioural endpoints. Behavioural responses under metals were in accordance with the Stepwise Behavioural Response model. Significant and concentration-dependent effects on swimming speed and turning times were found at concentrations equal to or higher than 3.5 mg L^-1 for zinc and 0.7 mg L^-1 for chromium. Swimming height significantly declined in concentrations equal to or higher than 3.5 mg L^-1 under zinc exposure, while for the chromium treatment, it significantly increased in lower concentration exposures and decreased in higher concentration exposures. Average distance and dispersion of fish school decreased at the beginning but there were no obvious changes during the whole exposure period. Behavioural responses under metal exposures were time-dependent: avoidance (increased speed and turning times and decreased average distance and dispersion) might be the first response and followed by height changes. Changes in behavioural endpoints ‘swimming speed and height’ can be used as early stress responses for acute aquatic metal contamination as part of ecological risk assessment.     

Age Dependence of Female to Male Fatality Risk in the Same Crash: An Independent Reexamination

A 1988 study reported that females are more likely than males to be killed by the same physical insult. This was determined by analyzing 1975–1983 data. The present study revisits this question using 123,678 fatalities from 1984–1996 data. As none of these data contributed to the earlier study, the present investigation is therefore independent of the earlier one. Female to male fatality risk ratios are calculated for 14 categories of vehicle occupants, including six light truck occupants (belted and unbelted drivers and right front passengers, and unbelted left and right rear passengers). The earlier study did not include light trucks. Close agreement is found between the results of the present and prior studies, thus solidifying the interpretation that findings are of a general nature and not dependent on specific data sets. Except at ages less than about 10 years, or older than about 55, females are more likely to be killed than males. While obtained using traffic data, the results are interpreted to reflect fundamental differences in human physiological response to blunt trauma in general, and are expected to apply to blunt trauma from falls, being struck by objects, etc.     

CdSe/ZnS量子点对斑马鱼胚胎发育的毒性效应

本研究以模式生物斑马鱼(Danio rerio)为对象,观察在不同浓度Cd Se/Zn S量子点(Cd Se/Zn S QDs)暴露下,斑马鱼胚胎形态发育、氧化应激以及金属硫蛋白MT基因和应激蛋白Hsp70基因表达变化情况.结果表明,Cd Se/Zn S QDs对斑马鱼胚胎72 hpf(hours post fertilization)的半致畸效应浓度(EC50)为316.994 nmol·L-1.QDs暴露影响了斑马鱼胚胎的死亡率、畸形率、孵化率、自主运动频率和体长,以及引起胚胎卵凝集,心包囊肿,脊椎弯曲等多种毒性效应;同时导致斑马鱼体内超氧化物歧化酶(SOD)活性变化以及丙二醛(MDA)含量增加.QDs还诱导斑马鱼MT基因和Hsp70基因表达上调,斑马鱼机体产生一系列自我保护反应来减轻QDs所造成的伤害.这表明:Cd Se/Zn S QDs对斑马鱼胚胎产生了毒性效应,其毒性可能与其核心Cd2+的释放、粒径大小以及氧化应激有关.     

T-2 toxin induces developmental toxicity and apoptosis in zebrafish embryos

T-2 toxin is one of the most important trichothecene mycotoxins occurring in various agriculture products. The developmental toxicity of T-2 toxin and the exact mechanism of action at early life stages are not understood precisely. Zebrafish embryos were exposed to different concentrations of the toxin at 4-6 hours post fertilization （hpf） stage of development, and were observed for different developmental toxic effects at 24, 48, 72, and 144 hpf. Exposure to 0.20 Ixmol/L or higher concentrations of T-2 toxin significantly increased the mortality and malformation rate such as tail deformities, cardiovascular defects and behavioral changes in early developmental stages of zebrafish. T-2 toxin exposure resulted in significant increases in reactive oxygen species （ROS） production and cell apoptosis, mainly in the tall areas, as revealed by Acridine Orange staining at 24 hpf. In addition, T-2 toxin-induced severe tail deformities could be attenuated by co-exposure to reduced glutathione （GSH）. T-2 toxin and GSH co-exposure induced a significant decrease of ROS production in the embryos. The overall results demonstrate that T-2 toxin is able to produce oxidative stress and induce apoptosis, which are involved in the developmental toxicity of T-2 toxin in zebrafish embryos.     

纳米氧化锌对斑马鱼肝脏的毒性效应

采用半静态急性实验方法,研究斑马鱼在浓度为0、0.05、0.1、5、10、25、50 mg·L-1的纳米氧化锌(nano-Zn O)中暴露4、24、96 h后,nano-Zn O对肝中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)的影响,肝脏中Bcl-2、Bax、p53和MDM2的mRNA表达量的变化以及暴露7、15、30 d时肝组织解剖结构变化情况.结果表明,与对照组相比,实验组表现为:1肝组织出现组织水肿,部分细胞质空泡化、细胞核固缩;2肝巨噬细胞增多,窦间隙增大;3肝中SOD活性升高、MDA含量增加、CAT活性降低;4肝脏中Bax/Bcl-2和p53的mRNA的表达量均升高;5 MDM2 mRNA的表达量表现为在低浓度组中降低,高浓度组中则升高.实验结果表明,nano-Zn O能引起斑马鱼肝脏发生氧化应激作用,使肝中抗氧化酶活性发生变化,并诱导肝脏中细胞凋亡相关基因的表达,使细胞发生凋亡且造成肝组织结构发生变化.     

Exposure to endocrine disrupting chemicals perturbs lipid metabolism and circadian rhythms

A growing body of evidence indicates that exposure to environmental chemicals can contribute to the etiology of obesity by inappropriately stimulating adipogenesis as well as perturbing lipid metabolism and energy balance. One potential mechanism by which chemical exposure can influence lipid metabolism is through disturbance of circadian rhythms, endogenously-driven cycles of roughly 24hr in length that coordinate biochemical, physiological, and behavioral processes in all organisms. Here we show for the first time that exposure to endocrine disrupting compounds (EDCs), including the pesticide tributyltin, two commercial flame retardants, and a UV-filter chemical found in sunscreens, can perturb both circadian clocks and lipid metabolism in vertebrates. Exposure of developing zebrafish to EDCs affects core clock activity and leads to a remarkable increase in lipid accumulation that is reminiscent of the effects observed for longdaysin, a known disruptor of circadian rhythms. Our data reveal a novel obesogenic mechanism of action for environmental chemicals, an observation which warrants further research. Because circadian clocks regulate a wide variety of physiological processes, identification of environmental chemicals capable of perturbing these systems may provide important insights into the development of environmentally-induced metabolic disease.     

林丹短期暴露对斑马鱼生长发育和繁殖的影响

以斑马鱼为受试生物,研究在低浓度(0.005、0.05、0.5峭μg·L-1)林丹暴露条件下,林丹对斑马鱼体长、体质量、肝脏指数、性腺指数、产卵量和受精率的影响.结果显示,经14 d暴露后,处理组斑马鱼体长和体质量与空白对照组或溶剂对照组之间差异不显著;与空白对照组和溶剂对照组相比,0.5μg·L-1处理组雄性和雌性斑马鱼肝脏指数均显著增加(P＜0.05),雄性斑马鱼性腺指数显著降低(P＜0.05),其他处理组无明显变化;林丹对斑马鱼产卵量和受精率表现出明显的抑制作用,与空白对照组相比,0.05和0.5μg·L-1处理组斑马鱼平均产卵量和受精率均极显著降低(P＜0.01).该研究表明林丹具有环境内分泌干扰物特性,在低浓度暴露条件下可对斑马鱼的生长发育和繁殖产生一定抑制影响.     

Female pseudohermaphroditism in a fetus with a deletion 9(q22.2q31.1)

Interstitial deletions of chromosomal region 9q are rarely seen. We report the first prenatal diagnosis of a de novo interstitial deletion 9q. The fetus was karyotyped for intrauterine growth retardation (IUGR). Conventional and molecular cytogenetics showed female karyotype with a de novo deletion of the chromosomal region 9(q22.2q31.1) leading to a partial monosomy 9q. At autopsy, the fetus showed growth retardation, dysmorphy, and a female pseudohermaphroditism. These results suggest that a gene(s) for genital development reside in chromosomal region 9q22.2q31.1. Copyright © 2002 John Wiley & Sons, Ltd.     

大气污染暴露与育龄妇女月经周期长度的关联

招募343名山西常住的育龄妇女,开展大气污染暴露与育龄妇女月经周期长度的横断面研究.基于妇女月经周期生理特点,设置大气污染暴露的时间窗口期.采集妇女所在城市的空气质量监测点大气SO₂、NO₂、PM_2.5和O₃的日报浓度,分别计算不同暴露时间的大气污染物浓度水平.采用广义线性模型,分析大气污染暴露与育龄妇女月经周期长度的关联效应,阐明大气污染暴露对妇女生育力的潜在健康风险.结果表明,当控制混杂因素后,妇女在SO₂暴露窗第1期(0.053,95%CI:0.022,0.083)、第2期(0.049,95%CI:0.02,0.078)和第3期(0.045;95%CI:0.017、0.073),Q4组SO₂的暴露水平与月经周期总长度呈显著的正相关;而且,SO₂与月经周期总长度的正相关主要表现在卵泡期长度的延长上.在NO₂暴露窗第1期(0.060,95CI:0.035,0.085)、第2期(0.056,95CI:0.030,...