Environmental hazards: evidence for effects on child health

The human fetus, child, and adult may experience adverse health outcomes from parental or childhood exposures to environmental toxicants. The fetus and infant are especially vulnerable to toxicants that disrupt developmental processes during relatively narrow time windows. This review summarizes knowledge of associations between child health and development outcomes and environmental exposures, including lead, methylmercury, polychlorinated biphenyls (PCBs), dioxins and related polyhalogenated aromatic hydrocarbons (PHAHs), certain pesticides, environmental tobacco smoke (ETS), aeroallergens, ambient air toxicants (especially particulate matter [PM] and ozone), chlorination disinfection by-products (DBPs), sunlight, power-frequency magnetic fields, radiofrequency (RF) radiation, residential proximity to hazardous waste disposal sites, and solvents. The adverse health effects linked to such exposures include fetal death, birth defects, being small for gestational age (SGA), preterm birth, clinically overt cognitive, neurologic, and behavioral abnormalities, subtle neuropsychologic deficits, childhood cancer, asthma, other respiratory diseases, and acute poisoning. Some environmental toxicants, notably lead, ionizing radiation, ETS, and certain ambient air toxicants, produce adverse health effects at relatively low exposure levels during fetal or child developmental time windows. For the many associations supported by limited or inadequate epidemiologic evidence, major sources of uncertainty include the limited number of studies conducted on specific exposure-outcome relationships and methodologic limitations. The latter include (1) crude exposure indices, (2) limited range of exposure levels, (3) small sample sizes, and (4) limited knowledge and control of potential confounders. Important knowledge gaps include the role of preconceptual paternal exposures, a topic much less studied than maternal or childhood exposures. Large longitudinal studies beginning before or during early pregnancy are urgently needed to accurately measure and assess the relative importance of parental and childhood exposures and evaluate relatively subtle health outcomes such as neuropsychologic and other functional deficits. Large case-control studies are also needed to assess the role of environmental exposures and their interactions with genetic factors in relatively uncommon outcomes such as specific types of birth defects and childhood cancers. There is also an urgent need to accelerate development and use of biomarkers of exposure and genetic susceptibility in epidemiologic studies. This review supports the priority assigned by international agencies to relationships between child health and air quality (indoor and outdoor), lead, pesticides, water contaminants, and ETS. To adequately address such priorities, governments and agencies must strengthen environmental health research capacities and adopt policies to reduce parental and childhood exposures to proven and emerging environmental threats.     

Aortic dissection associated with cogans's syndrome: deleterious loss of vascular structural integrity is associated with GM-CSF overstimulation in macrophages and smooth muscle cells

Background  

Cogan's syndrome is a rare disorder of unknown origin characterized by inflammatory ocular disease and vestibuloauditory symptoms. Systemic vasculitis is found in about 10% of cases.     

Management of Epiphrenic Diverticula and Short-term Outcomes

1. Download : Download high-res image (75KB)
2. Download : Download full-size image

     

Treatment of asymptomatic gunshot injuries to the spine

Gunshot wounds to the spine and spinal canal are usually associated with significant neurologic loss. When this occurs, treatment is usually supportive, the predominant indication for surgical intervention being progression of the deficit. If the deficit does not progress, but a spinal block can be demonstrated to persist beyond the acute injury period, surgical decompression may also be indicated. When no neurologic deficit is present, the optimum approach is less clear. Complications such as infection or persistent cerebrospinal fluid (CSF) leak may necessitate surgical repair in asymptomatic patients, as well as those with neurologic loss. The presence of copper in the spinal canal is also considered by some to be an indication for surgical intervention in both groups.     

Monocyte chemotaxis and chemotactic cytokine release after exposure to hydroxyethyl starch

Hydroxyethyl starch (HES) is commonly used in leukapheresis and infused as an alternative to blood components for the treatment of hypotension due to hemorrhage and trauma. Its prolonged intravascular persistence and retention in tissue raise concerns about possible effects on humoral and cell-mediated immunity and white cell (WBC) locomotion, particularly in volunteer WBC donors or in severely burned individuals with immunologic depression and increased risk for infection. This study evaluated the effect of HES on human monocyte migration and chemotaxis and the production of antigen- and mitogen-induced WBC-derived chemotactic cytokine. A bioassay was developed to quantitate the neutrophil chemotactic activity of a cytokine generated by mononuclear WBCs stimulated in vitro by phytohemagglutinin or tuberculin protein. The time- and dose-dependent generation of the chemotactic cytokine was not affected by the presence of HES. HES by itself did not induce the generation of this cytokine, nor were human monocyte chemotaxis and spontaneous migration significantly changed by exposure to HES. These results, with those of other investigators, suggest that HES is a safe red cell-sedimenting agent for leukapheresis and an alternative to the use of blood components in shock resuscitation.     

甲真菌病治疗指南

该指南是英国皮肤科医师协会针对皮肤科医生制定的 ,反映了当前文献报道中的最新研究资料。在解释这些资料时应慎重 ,因为未来的研究可能会改变现有的结论或推荐方案。在应用该指南时 ,需因人而异 ,因地制宜。遵守指南并不能确保万无一失 ,因此对实施指南时的偏离不应都归咎于疏忽 (该指南并不能保证面面俱到 ,在实际应用中可加以变通 )。简介 :甲真菌病是最常见的皮肤病之一。英国对 10 0 0 0人进行的一项大规模问卷调查显示发病率为 2 71%。芬兰和美国最近的真菌学对照调查表明 ,发病率为 7%～ 10 %。甲真菌病发病率的升高和有效抗真菌新…