Introduction: All decapod crustaceans are considered potentially susceptible to White Spot Syndrome Virus (WSSV) infection, but the degree of White Spot Disease (WSD) susceptibility varies widely between species. The European shore crab can be infected with the virus for long periods of time without signs of disease. Given the high mortality rate of susceptible species, the differential susceptibility of these resistant hosts offers an opportunity to investigate mechanisms of disease resistance.
View Article and Find Full Text PDFA small pilot study was conducted to test whether the technique of in vivo neutron activation analysis could measure bone aluminum levels in 15 miners who had been exposed to McIntyre Powder over 40 years prior. All miners were over 60 years of age, had worked in mines that used McIntyre Powder, and were sufficiently healthy to travel from northern to southern Ontario for the measurements. Individual aluminum levels were found to be significantly greater than zero with 95% confidence ( < 0.
View Article and Find Full Text PDFIntricate links between aquatic animals and their environment expose them to chemical and pathogenic hazards, which can disrupt seafood supply. Here we outline a risk schema for assessing potential impacts of chemical and microbial hazards on discrete subsectors of aquaculture-and control measures that may protect supply. As national governments develop strategies to achieve volumetric expansion in seafood production from aquaculture to meet increasing demand, we propose an urgent need for simultaneous focus on controlling those hazards that limit its production, harvesting, processing, trade and safe consumption.
View Article and Find Full Text PDFWhite Spot Disease (WSD) presents a major barrier to penaeid shrimp production. Mechanisms underlying White Spot Syndrome Virus (WSSV) susceptibility in penaeids are poorly understood due to limited information related to early infection. We investigated mRNA and miRNA transcription in over 36 h following infection.
View Article and Find Full Text PDFWhite Spot Syndrome Virus (WSSV) causes White Spot Disease (WSD) and is historically the most devastating disease in the shrimp industry. Global losses from this disease have previously exceeded $3 bn annually, having a major impact on a global industry worth US$19 bn per annum. Shrimp are cultured predominantly in enclosed ponds that are subject to considerable fluctuations in abiotic conditions and WSD outbreaks are increasingly linked to periods of extreme weather, which may cause major fluctuations in pond culture conditions.
View Article and Find Full Text PDFInfect Control Hosp Epidemiol
November 2019
Introduction and regular application of multiplex polymerase chain reaction analysis of bronchoalveolar specimens for community-acquired respiratory viruses in January 2017 led to the identification of adenovirus in multiple patients in a surgical intensive unit in July 2017, which was attributed to a pseudo-outbreak.
View Article and Find Full Text PDFDiclofenac is one of the most widely prescribed nonsteroidal anti-inflammatory drugs worldwide. It is frequently detected in surface waters; however, whether this pharmaceutical poses a risk to aquatic organisms is debated. Here we quantified the uptake of diclofenac by the fathead minnow (Pimephales promelas) following aqueous exposure (0.
View Article and Find Full Text PDFHypoxia is a global and increasingly important stressor in aquatic ecosystems, with major impacts on biodiversity worldwide. Hypoxic waters are often contaminated with a wide range of chemicals but little is known about the interactions between these stressors. We investigated the effects of hypoxia on the responses of zebrafish (Danio rerio) embryos to copper, a widespread aquatic contaminant.
View Article and Find Full Text PDFSince its emergence in the 1990s, White Spot Disease (WSD) has had major economic and societal impact in the crustacean aquaculture sector. Over the years shrimp farming alone has experienced billion dollar losses through WSD. The disease is caused by the White Spot Syndrome Virus (WSSV), a large dsDNA virus and the only member of the Nimaviridae family.
View Article and Find Full Text PDFBackground: The European shore crab, Carcinus maenas, is used widely in biomonitoring, ecotoxicology and for studies into host-pathogen interactions. It is also an important invasive species in numerous global locations. However, the genomic resources for this organism are still sparse, limiting research progress in these fields.
View Article and Find Full Text PDFInbreeding depression is expected to be more severe in stressful environments. However, the extent to which inbreeding affects the vulnerability of populations to environmental stressors, such as chemical exposure, remains unresolved. Here we report on the combined impacts of inbreeding and exposure to an endocrine disrupting chemical (the fungicide clotrimazole) on zebrafish (Danio rerio).
View Article and Find Full Text PDFOutbred laboratory animal strains used in ecotoxicology are intended to represent wild populations. However, breeding history may vary considerably between strains, driving differences in genetic variation and phenotypes used for assessing effects of chemical exposure. We compared a range of phenotypic endpoints in zebrafish from four different "breeding treatments" comprising a Wild Indian Karyotype (WIK) zebrafish strain and a WIK/Wild strain with three levels of inbreeding (F(IT)=n, n+0.
View Article and Find Full Text PDFLaboratory animals tend to be more inbred and less genetically diverse than wild populations, and thus may differ in their susceptibility to chemical stressors. We tested this hypothesis by comparing the responses of related inbred (theoretical inbreeding F(IT) = n + 0.25) and outbred (F(IT) = n) zebrafish (Danio rerio) WIK/Wild family lines to an endocrine disrupting chemical, clotrimazole.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
November 2009
Exposure to environmental chemicals can have negative consequences for wildlife and even cause localized population extinctions. Resistance to chemical stress, however, can evolve and the mechanisms include desensitized target sites, reduced chemical uptake and increased metabolic detoxification and sequestration. Chemical resistance in wildlife populations can also arise independently of exposure and may be spread by gene flow between populations.
View Article and Find Full Text PDFThe presence of endocrine disrupting chemicals (EDCs) in the environment has driven the development of screening and testing assays to both identify chemicals with hormonal activity and evaluate their potential to cause adverse effects. As the number of animals used for research and regulatory purposes rises, and set against a desire to reduce animal testing, there is increased emphasis on the development and application of in vitro techniques to evaluate chemical risks to the environment. Induction of vitellogenin (VTG) in isolated fish liver cells has been used successfully to identify a wide range of EDCs, including both natural and synthetic oestrogens and a variety of other xenoestrogens.
View Article and Find Full Text PDFMany factors have been considered in evaluations of the risk-benefit balance of hormone replacement therapy (HRT), used for treating menopausal symptoms in women, but not its potential risks for the environment We investigated the possible environmental health implications of conjugated equine estrogens (CEEs), the most common components of HRT, including their discharge into the environment, their uptake, potency, and ability to induce biological effects in wildlife. Influents and effluents from four U.K.
View Article and Find Full Text PDFHealth Serv Manage Res
August 2002
A balance should be reached between physician productivity and clinical quality, since the first comes at the expense of the second. The study described here used the National Ambulatory Medical Care Survey (NAMCS) to demonstrate that visit length for elderly heart disease patients is related to both appropriate (i.e.
View Article and Find Full Text PDFBackground And Objectives: To determine the impact of international health experiences on physicians in training, we studied 60 US medical students who participated in an International Health Fellowship Program (IHFP).
Methods: In 1995 and 1996, US medical students were selected to participate in the IHFP, which included training at three US medical schools and at seven medical schools in developing countries. The program included a 2-week preparatory course at a US school and a 6- to 8-week field experience.
We describe two patients with sustained myoglobinuria that did not resolve with supportive treatment. After we established a diagnosis of dermatomyositis and started treatment with corticosteroids, there was rapid resolution of the myoglobinuria. Well-documented cases of inflammatory myopathy causing myoglobinuria are rare, but their prompt recognition has important therapeutic implications.
View Article and Find Full Text PDFThe International Health Medical Education Consortium (IHMEC) is the first national organization created to link faculty in North American medical schools that teach international health. This article presents IHMEC's role in international medical education, including their mission, structure, and future agendas.
View Article and Find Full Text PDFPurpose: To evaluate the radiologic characteristic of acute inflammation of the epiglottis and supraglottic structures in adults.
Methods: The clinical and radiographic findings in 27 adult patients with epiglottitis (average age, 43 years; range, 28 to 81 years) were compared with those of a control group of asymptomatic subjects (n = 15; average age, 48 years; range, 24 to 79 years). Unusual clinical aspects in the current series included two patients who were positive for human immunodeficiency virus, 1 with acquired immunodeficiency syndrome and Kaposi sarcoma, 3 with emphysematous epiglottitis, 1 with abscess formation, and 1 with laryngeal carcinoma.