985 resultados para ENVIRONMENTAL HEALTH


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Throughout the world, biomonitoring has become the standard for assessing exposure of individuals to toxic elements as well as for responding to serious environmental public health problems. However, extensive biomonitoring surveys require rapid and simple analytical methods. Thus, a simple and high-throughput method is proposed for the determination of arsenic (As), cadmium (Cd), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se) in blood samples by using inductively coupled plasma–mass spectrometry (ICPMS). Prior to analysis, 200 ml of blood samples was mixed with 500 ml of 10% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 10 min, and subsequently diluted to 10 ml with a solution containing 0.05% w/v ethylenediamine tetraacetic acid (EDTA) + 0.005% v/v Triton X-100. After that, samples were directly analyzed by ICP-MS (ELAN DRC II). Rhodium was selected as an internal standard with matrix-matching calibration. Method detection limits were 0.08, 0.04, 0.5, 0.09, 0.12, 0.04, and 0.1 mg//L for As, Cd, Cu, Mn, Ni, Pb, and Se, respectively. Validation data are provided based on the analysis of blood samples from the trace elements inter-\comparison program operated by the Institut National de Santé Publique du Quebec, Canada. Additional validation was provided by the analysis of human blood samples by the proposed method and by using electrothermal atomic absorption spectrometry (ETAAS). The method was subsequently applied for the estimation of background metal blood values in the Brazilian population. In general, the mean concentrations of As, Cd, Cu, Mn, Ni, Pb, and Se in blood were 1.1, 0.4, 890, 9.6, 2.1, 65.4, and 89.3 mg/L, respectively, and are in agreement with other global populations. Influences of age, gender, smoking habits, alcohol consumption, and geographical variation on the values were also considered. Smoking habits influenced the levels of Cd in blood. The levels of Cu, Mn, and Pb were significantly correlated with gender, whereas Cu and Pb were significantly correlated with age. There were also interesting differences in Mn and Se levels in the population living in the north of Brazil compared to the south.

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The Brazilian federal government Agency for Health Surveillance detected pesticide residues in fresh food available for consumers all over the country. The current study investigated the effects of a mixture of some of those pesticides (dichlorvos, dicofol, dieldrin, endosulfan, and permethrin) on the reproductive system of Sprague-Dawley (SD), Wistar (WT), and Lewis (LEW) rats. Female rats from each strain were randomized into three experimental groups and were fed a control diet or diets added with pesticides mixture at their respective no-observed-effect level (NOEL)/no-observed-adverse-effect level (NOAEL) (low dose) (mg/kg/d): dichlorvos (0.23), dicofol (0.5), dieldrin (0.025), endosulfan (0.7), permethrin (5), or lowest-observed-effect level (LOEL)/lowest-effect level (LEL)/ lowest-observed-adverse-effect level (LOAEL) (toxically effective dose) (mg/kg/d): dichlorvos (2.3), dicofol (2.1), dieldrin (0.05), endosulfan (3.8), and permethrin (25) as reported in the literature. Euthanasia was performed between wk 10 and 12, during the estrous stage. Decreased body weights gain (SD and WT) and increased liver weights (SD, WT, and LEW) were observed in each strain fed the pesticides mixture at the higher levels. At that dose level, rat strains also varied in their responses regarding the estrous cycle, hormonal levels, and number of developing ovarian follicles. The studied mixture of pesticides was found to interfere with the female reproductive system when individual pesticides were mixed above a certain level, indicating a threshold exists for each of the strains studied.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Interferon-alpha (IFN- α ), a type I IFN, is a protein with antiviral, antiproliferative, and immunoregulatory activities, widely used in the treatment of several types of cancers as well as hepatitis B and C. Decrease of libido and erectile dysfunction are commonly reported by male patients during treatment of chronic hepatitis C with IFN- α . However, IFN therapy-associated underlying factors attributed to sexual dysfunction are still not well defined. Currently, there are few studies investigating the effects of IFN on male reproductive system functions. Given that, the aim of the present investigation was to examine effects of subchronic exposure to IFN- α (5 × 10(4) U/kg and 10 × 10(4) U/kg, 30 d) on serum hormones, sperm parameters, fertility, and testicular and epididymal hystopathology and morphometry in adult male Wistar rats. None of the evaluated parameters was markedly altered by IFN- α . Thus, our results suggest that exposure to IFN- α , in this experimental design, did not adversely affect sperm quality and fertile capacity of male rats.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Table of Contents: Recovering the New England Cottontail FOCUS..Ready for Tomorrow Build It and They Will Come CARE: Restoring America’s Wildlife Refuges

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Table of Contents: Liberating Rat Island, page 4 Focus on . . . Through the Eyes of Children, pages 10-19 Back to Midway, page 23

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Table of Contents: Friends Flourish, page 3 Yukon Delta Refuge Hosts Major Shorebird Research, pages 4-5 Focus on…Nature Photography, pages 8-14 Learning a New Language, pages 18-19

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Table of Contents: Recreation Fees Change the Face of Refuges, page 4 Focus on Cultural Resources, page 8 “Ambassadorship” is Thriving in Texas, page 15 BayScaping: Conserving Views and Habitats, page 16

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Table of Contents: Crystal River’s Manatee Rescue Squad, page 3 Focus on . . . Birds and Birding, pages 8-15 Assessing Damage in an Arizona Wilderness, page 16 Have Hammers, Will Travel page 18

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Table of Contents: America’s Birds: In an Alarming State Snakes Alive! Title Sub Title East Coast Wetlands Are Disappearing Chief’s Corner: What We Do Now Extreme Makeover for Bird Sightings by Mike Carlo Taking Care of Our World War II Legacy by Lisa Matlock Whatever Happened to . . . . San Francisco Bay Wetland Restoration Projects Recalling the Battle of Long Island Sound by David Klinger Bold Approaches for Climate Change How Alligator River Refuge Is Planning and Adapting by Mike Bryant Rapid Climate Change Is Transforming the Arctic by David Payer Tracking Change on Wildlife Refuges by Kathy Granillo Where SLAMM Foretells a Wetter Future Reviving the Land – and the Air by Bob Ford and Pete Jerome Connecting the Conservation Landscape a New Priority by Mike Scott and Bob Adamcik Awards for Refuge System Palmyra Atoll Refuge Becomes Ramsar Site Not So Strategic Habitat Conservation: A True Story by David Viker Putting Food on Alaskan Tables by Andy Aderman

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Table of Contents: Energy Company Fine Benefits Ottawa Refuge, page 3 Hide and Seek…but Mostly Hide page 4 Focus on …Pollinators, page 10 Great Storytellers, page 18

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Table of Contents: What’s Melting: Togiak Refuge Sizes Up Its Glaciers, page 3 Focus on Fish Conservation, pages 10-15 Whatever happened to…, pages 16-17 Wildlife Cooperatives, page 20

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Table of Contents: An Encyclopedia for the Refuge, page 4 Awarded for Excellence, page 5 MBNA Donates for Refuge System Projects, page 16 The Thoughts of a Detailee, page 19