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1.
Front Public Health ; 7: 67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019905

RESUMO

Board member education must be elevated within the curricula of leadership development programming in Low and Middle Income Countries (LMICs) across the globe. When properly trained and supported, the community, business, and health sector leaders serving on these boards can create the conditions within which those who deliver and manage health services are more likely to successfully achieve the mission of their organizations. The importance of incorporating education for governing body members into health sector leadership development programming, and three strategies for board development, are defined in in this article.

2.
J Surg Case Rep ; 2018(8): rjy185, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30093989

RESUMO

Merkel cell carcinoma (MCC) is a rare, aggressive carcinoma that usually arises in sun-exposed regions. MCC is a primary neuroendocrine tumor that arises in the skin. This report describes an unusual case of MCC on the buttocks that was treated with excision, radiation and chemotherapy. Physicians should consider MCC as a differential diagnosis when encountering a rapidly growing, painless lesion. Early diagnosis and treatment may improve patient survival rates.

3.
Sci Total Environ ; 643: 73-89, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29935363

RESUMO

Endocrine active compounds (EACs) are pollutants that have been recognized as an emerging and widespread threat to aquatic ecosystems globally. Intersex, the presence of female germ cells within a predominantly male gonad, is considered a biomarker of endocrine disruption caused by EACs. We measured a suite of EACs and assessed their associated impacts on fish intersex occurrence and severity in a large, regulated river system in North Carolina and South Carolina, USA. Our specific objective was to determine the relationship of contaminants in water, sediment, and fish tissue with the occurrence and severity of the intersex condition in wild, adult black bass (Micropterus), sunfish (Lepomis), and catfish (Ictaluridae) species at 11 sites located on the Yadkin-Pee Dee River. Polycyclic aromatic hydrocarbons (PAHs), ethinylestradiol (EE2), and heavy metals were the most prevalent contaminants that exceeded effect levels for the protection of aquatic organisms. Fish intersex condition was most frequently observed and most severe in black basses and was less frequently detected and less severe in sunfishes and catfishes. The occurrence of the intersex condition in fish showed site-related effects, rather than increasing longitudinal trends from upstream to downstream. Mean black bass and catfish tissue contaminant concentrations were higher than that of sunfish, likely because of the latter's lower trophic position in the food web. Principal component analysis identified waterborne PAHs as the most correlated environmental contaminant with intersex occurrence and severity in black bass and sunfish. As indicated by the intersex condition, EACs have adverse but often variable effects on the health of wild sport fishes in this river, likely due to fluctuations in EAC inputs and the dynamic nature of the riverine system. These findings enhance the understanding of the relationship between contaminants and fish health and provide information to guide ecologically comprehensive conservation and management decisions.


Assuntos
Transtornos do Desenvolvimento Sexual/veterinária , Monitoramento Ambiental , Doenças dos Peixes/epidemiologia , Peixes/fisiologia , Poluentes Químicos da Água/análise , Animais , Transtornos do Desenvolvimento Sexual/epidemiologia , Feminino , Masculino , North Carolina , Rios/química , South Carolina , Esportes , Poluição Química da Água/estatística & dados numéricos
4.
Environ Sci Technol ; 51(9): 5296-5305, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28379677

RESUMO

Estrogens and estrogen mimics are commonly found in surface waters and are associated with deleterious effects in fish populations. Impaired fertility and fecundity in fish following chronic exposures to estrogens and estrogen mimics during critical windows in development are well documented. However, information regarding differential reproductive effects of exposure within defined developmental stages remains sparse. In this study, reproductive capacity was assessed in Japanese medaka (Oryzias latipes) after exposure to two concentrations of 17ß-estradiol (E2ß; 2 ng/L and 50 ng/L) during four distinct stages of development: gonad development, gonad differentiation, development of secondary sex characteristics (SSC) and gametogenesis. Exposure to E2ß did not adversely impact survival, hatch success, growth, or genotypic ratios. In contrast, exposure to 50 ng/L E2ß during SSC development altered phenotypic ratios and SSC. Exposure to both E2ß treatments reduced reproductive capacity (fertility, fecundity) by 7.3-57.4% in adult medaka breeding pairs, with hindrance of SSC development resulting in the largest disruption in breeding capacity (51.6-57.4% decrease) in the high concentration. This study documents differential effects among four critical stages of development and provides insight into factors (window of exposure, exposure concentration and duration of exposure period) contributing to reproductive disruption in fish.


Assuntos
Estradiol/farmacologia , Oryzias , Animais , Gônadas/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos
5.
Environ Toxicol Chem ; 36(4): 959-968, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27583571

RESUMO

Male fish are susceptible to developing intersex, a condition characterized by the presence of testicular oocytes. In the present study, the relationship between intersex and exposure to estrogenic endocrine active contaminants (EACs) was assessed for 2 genera of sport fish, Micropterus and Lepomis, at 20 riverine sites. Seasonal trends and relationships between EACs and intersex (prevalence and severity) were examined at varying putative sources of EACs throughout North Carolina, identified as point sources, nonpoint sources, and reference sites. Intersex was identified in both genera, which was documented for the first time in wild-caught Lepomis. Intersex was more prevalent (59.8%) and more severe (1.6 mean rank) in Micropterus, which was highly correlation to EACs in sediment. In contrast, intersex was less common (9.9%) and less severe (0.2 mean rank) in Lepomis and was highly correlated to EACs in the water column. The authors found that concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, industrial EACs, and estrogens were highest at point source sites; however, no source type variation was identified in the prevalence or severity of intersex, nor were there seasonal trends in intersex or EAC concentrations. The authors' results associate genus-specific prevalence of intersex with specific EAC classes in common sport fishes having biological, ecological, and conservation implications. Environ Toxicol Chem 2017;36:959-968. © 2016 SETAC.


Assuntos
Bass/crescimento & desenvolvimento , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Disruptores Endócrinos/análise , Sistema Endócrino/efeitos dos fármacos , Rios/química , Poluentes Químicos da Água/análise , Animais , Bass/metabolismo , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental , Feminino , Masculino , North Carolina , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Estações do Ano , Especificidade da Espécie , Esportes , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade
6.
Environ Toxicol Chem ; 34(2): 437-45, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25378272

RESUMO

The presence of endocrine-disrupting compounds (EDCs), particularly estrogenic compounds, in the environment has drawn public attention across the globe, yet a clear understanding of the extent and distribution of estrogenic EDCs in surface waters and their relationship to potential sources is lacking. The objective of the present study was to identify and examine the potential input of estrogenic EDC sources in North Carolina water bodies using a geographic information system (GIS) mapping and analysis approach. Existing data from state and federal agencies were used to create point and nonpoint source maps depicting the cumulative contribution of potential sources of estrogenic EDCs to North Carolina surface waters. Water was collected from 33 sites (12 associated with potential point sources, 12 associated with potential nonpoint sources, and 9 reference), to validate the predictive results of the GIS analysis. Estrogenicity (measured as 17ß-estradiol equivalence) ranged from 0.06 ng/L to 56.9 ng/L. However, the majority of sites (88%) had water 17ß-estradiol concentrations below 1 ng/L. Sites associated with point and nonpoint sources had significantly higher 17ß-estradiol levels than reference sites. The results suggested that water 17ß-estradiol was reflective of GIS predictions, confirming the relevance of landscape-level influences on water quality and validating the GIS approach to characterize such relationships.


Assuntos
Disruptores Endócrinos/análise , Sistemas de Informação Geográfica , Poluentes Químicos da Água/análise , Estradiol/análise , Estrogênios/análise , Geografia , Análise dos Mínimos Quadrados , Modelos Teóricos , North Carolina
7.
J Hazard Mater ; 279: 244-56, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25064262

RESUMO

The tentative connection between the biochar surface chemical properties and their influence on microbially mediated mineralization of C, N, and S with the help of enzymes is not well established. This study was designed to investigate the effect of different biomass conversion processes (microwave pyrolysis, carbon optimized gasification, and fast pyrolysis using electricity) on the composition and surface chemistry of biochar materials produced from corn stover (Zea mays L.), switchgrass (Panicum virgatum L.), and Ponderosa pine wood residue (Pinus ponderosa Lawson and C. Lawson) and determine the effect of biochars on mineralization of C, N, and S and associated soil enzymatic activities including esterase (fluorescein diacetate hydrolase, FDA), dehydrogenase (DHA), ß-glucosidase (GLU), protease (PROT), and aryl sulfatase (ARSUL) in two different soils collected from footslope (Brookings) and crest (Maddock) positions of a landscape. Chemical properties of biochar materials produced from different batches of gasification process were fairly consistent. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity, irrespective of biomass feedstock and pyrolytic process. The short term incubation study showed that biochar had negative effects on microbial activity (FDA and DHA) and some enzymes including ß-glucosidase and protease.


Assuntos
Carvão Vegetal/química , Microbiologia do Solo , Biomassa , Carbono/química , Enzimas/análise , Microscopia Eletrônica de Varredura , Nitrogênio/química , Panicum/química , Pinus/química , Enxofre/química , Zea mays/química
8.
Microsc Microanal ; 20(2): 521-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24572008

RESUMO

Natural organic matter (NOM) generically refers to organic substances found in soils, waters, and sediments. It is the brown-to-black, heterogeneous organic material produced through the diagenetic alteration of plant tissue and microbial biomass via a myriad of biotic and abiotic reactions. Since NOM is the primary source of organic carbon in the earth's surficial environment, understanding the processes by which NOM is produced is integral to understanding carbon sequestration, contaminant fate and transport, and other earth surface processes. NOM samples (HA0) consist of nonamphiphilic (HA1), lipid-like (L0 and L1), and strongly amphiphilic (HA2) components. Here we present the structure and morphology of self-assembled NOM components based on scanning electron microscopy (SEM), atomic force microscopy (AFM), and electrostatic force microscopy (EFM) characterizations. Effects of surface charge and hydrophobicity/hydrophilicity of the amphiphile on the interaction and resulting structures were investigated using SEM, AFM, and EFM. Data shows that the component's amphiphilic nature plays a key role in the formation of NOM. SEM data show that aggregates form while AFM/EFM analysis verifies the existence of hydrophobic/hydrophilic moieties in different fractions of HA0. Subsequently, the amphiphilic nature of HA2 will have a substantial effect on interfacial interactions and subsequent self-assembly of HA0's components.


Assuntos
Substâncias Húmicas/análise , Microscopia de Força Atômica , Microscopia Eletrônica , Tamanho da Partícula , Propriedades de Superfície , Meio Ambiente
9.
Environ Pollut ; 178: 493-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23597802

RESUMO

Maternal transfer of mercury in fish represents a potential route of elimination for adult females and a risk to developing embryos. To better quantify maternal transfer, we measured Hg in female largemouth bass (Micropterus salmoides) muscle and eggs from six waterbodies. Mercury in eggs from two waterbodies exceeded a US federal screening level (0.3 µg g(-1)) and was likely high enough to cause adverse reproductive effects. We found a curvilinear relationship between female and egg Hg. Fish with <0.37 µg g(-1) Hg had low levels of Hg in eggs; those with Hg >0.37 µg g(-1) showed a direct relationship between egg and muscle Hg (Log10 egg Hg = -1.03 + 1.18 * log10 muscle tissue Hg + 2.15 * (log10 muscle tissue Hg + 0.35)(2)). We also report higher maternal transfer (0.2-13.2%) and higher ratios of egg to muscle tissue Hg (4-52%) and egg to whole body Hg concentrations (7-116%) than previously observed for teleost fish.


Assuntos
Bass/metabolismo , Embrião não Mamífero/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Monitoramento Ambiental , Feminino , Reprodução
10.
Int J Environ Res Public Health ; 10(2): 638-59, 2013 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-23388852

RESUMO

Consumption of fish has well-known human health benefits, though some fish may contain elevated levels of mercury (Hg) that are especially harmful to developing children. Fish length is most often the basis for establishing fishery harvest regulations that determine which fish will ultimately be consumed by humans. It is, therefore, essential to quantify the relationship between fish length and Hg accumulation in regard to harvest regulations for effective fishery and public health policy. We examined this relationship for three sportfish from six lakes across North Carolina, USA. Bluegill (Lepomis macrochirus) had the lowest Hg levels and only the very largest fish in the most contaminated site exceeded the US Environmental Protection Agency (USEPA) Hg screening level. Black crappie (Pomoxis nigromaculatus) had an intermediate level of Hg and larger individuals exceeded the USEPA screening level; however, they tended not to exceed this level before reaching the harvest length limit. Largemouth bass (Micropterus salmoides) exceeded the USEPA screening level at sizes below the fishery length limit in two lakes, leaving only higher risk fish for anglers to harvest and consume. Removing the effects of fish age and trophic position, we found strong positive correlations between Hg and fish length for largemouth bass and black crappie. We suggest public health officials and wildlife managers collaborate to structure fishery regulations and length-based fish consumption advisories that protect consumers from Hg exposure and communicate the relative risk of fish consumption.


Assuntos
Mercúrio/análise , Perciformes/anatomia & histologia , Poluentes Químicos da Água/análise , Animais , Tamanho Corporal , Conservação dos Recursos Naturais , Monitoramento Ambiental , Feminino , Contaminação de Alimentos/análise , Humanos , Masculino , North Carolina , Medição de Risco
11.
Chemosphere ; 84(4): 519-26, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21458839

RESUMO

The chemical composition and physical conformation of natural organic matter (NOM) play a major role in regulating its capacity to retain hydrophobic organic compounds. Naphthalene and phenanthrene were used to study the correlations between sorption/desorption isotherm nonlinearity and compositional data obtained from quantitative (13)C solid-state DPMAS NMR spectroscopy for soil and peat organic matter with or without lipids. Sorption experiments were conducted using a batch equilibration method. Desorption experiments were carried out immediately following the sorption experiments by three successive decant-refill cycles. Hysteresis was observed in all samples. Nonlinear sorption behavior was increased by removal of lipids from the NOM. The hysteresis index, obtained from the ratio of the Freundlich exponents (N values) for the desorption and sorption isotherms, was lower in the lipid-extracted NOM samples than in the same samples without lipid extraction. The relationship between the extent of hysteresis and the characteristics of the (13)C DPMAS NMR spectra indicates that altering NOM composition through lipid extraction not only increased the proportion of aromatic-C content, but also increased sorption/desorption hysteresis. Our data also suggest that the hysteresis index is negatively related to aromaticity.


Assuntos
Substâncias Húmicas , Lipídeos/química , Naftalenos/química , Fenantrenos/química , Poluentes do Solo/química , Adsorção , Modelos Químicos
12.
Ecotoxicology ; 19(8): 1601-11, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20848188

RESUMO

Much of the mercury contamination in aquatic biota originates from coal-fired power plants, point sources that release mercury into the atmosphere. Understanding mercury dynamics is primarily important because of the toxic threat mercury poses to wildlife and humans through the consumption of contaminated fish. In this study, we quantified the relative importance of proximity to coal-fired power plants on mercury accumulation in two fish species of different trophic positions. Fish, water and sediment were collected and analyzed from 14 lakes, seven near to (<10 km) and seven far from (>30 km) coal-fired power plants. Lower tissue mercury and higher tissue selenium concentrations were measured in fish collected near power plants. Moreover, mercury accumulation in fish was driven by biotic characteristics (e.g., trophic position, total length, age), waterbody characteristics (e.g., pH, dissolved organic carbon and sulfate) and distance from power plants. Proximity to an atmospheric point-source of mercury and selenium, such as a coal-fired power plant, affects the quantities of mercury and selenium accumulated in fish tissue. Differences in accumulation are hypothesized to be driven in part by selenium-mitigated reductions in fish tissue mercury near power plants. Although reduced fish tissue mercury in systems near power plants may decrease mercury-specific risks to human consumers, these benefits are highly localized and the relatively high selenium associated with these tissues may compromise ecological health.


Assuntos
Peixes/metabolismo , Mercúrio/metabolismo , Centrais Elétricas , Poluentes Químicos da Água/metabolismo , Animais , Carvão Mineral , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Água Doce , Sedimentos Geológicos/química , Humanos , Mercúrio/toxicidade , Selênio/metabolismo , Especificidade da Espécie , Distribuição Tecidual , Poluentes Químicos da Água/toxicidade
14.
Water Environ Res ; 81(11): 2299-308, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19957761

RESUMO

This paper introduces a novel natural organic matter (NOM) fractionation technique using solid-phase extraction cartridges. The new technique requires only 6 hours of fractionation time, which is much faster than traditional fractionation techniques (24 hours). It uses three Bond Elute ENV cartridges (Varian, Inc., Lake Forest, California), one Strata X-C cartridge (Phenomenex, Torrance, California), and one Strata X-AW cartridge (Phenomenex) in series and was tested by using to fractionate NOM from Suwannee River, Georgia (SRNOM) and Red River, Minnesota (RRNOM). Hydrophobic acid was a major fraction and accounted for 66 to 70% and 36% of SRNOM and RRNOM, respectively. The NOM fractions obtained from the developed method were characterized using Fourier transformed infrared spectroscopy and 13C nuclear magnetic resonance. The acid fractions of SRNOM mainly consisted of carboxylic acids. An application of this new technique was demonstrated by using it to investigate the effectiveness of water treatment processes in removing different NOM fractions.


Assuntos
Água Doce/química , Substâncias Húmicas/análise , Compostos Orgânicos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Isótopos de Carbono , Espectroscopia de Ressonância Magnética , Microextração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Langmuir ; 25(16): 9012-5, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19408899

RESUMO

Studies of the structural organization of humic acid in solution have suggested that it is composed of three fractions, two humic acid-like and one lipid-like, that have distinct roles in the process of its self-organization. The present work extends the study of humic acid's structural organization to the solid state by directly comparing its organization with a physical mixture composed of its three fractions using differential scanning calorimetry. Comparative measurements of the specific heat capacity as a function of temperature reveal differences between the original humic acid and the mixture with the same chemical composition. These differences provide direct evidence that humic acid's solid state structure is more than just a mixture of components and is determined by specific interactions between its components. This study indicates that humic acid in the solid state has a hierarchical or "structure within a structure" architecture. The lower-level structure is determined by the self-assembly of amphiphilic components of humic acid with lipids into a nanostructured composite material. A higher-level structure is formed by the association of this composite material with the nonamphiphilic components of humic acid.

17.
AHP J ; : 8-9, 11-2, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18551788

RESUMO

Philanthropy has taken center stage again after the rapid growth of hospitals in the 1990s. It is an essential resource, not only because today's hospitals need the money more than ever, but also because great philanthropy helps forge rewarding relationships with the community. In meetings with more than 1,000 hospital board members and leaders at The Governance Institute's 2007 conferences, it became clear that maximizing philanthropy in the future will require boards to enhance three initiatives: a bolder service mission, more effective stakeholder engagement tools and enhanced planned giving programs. Health care philanthropy boards and the boards of their related organizations would be wise to devote time for robust conversations about their strategies for feeding the voracious capital appetites of contemporary health care systems and for examining their ability to govern a new generation of philanthropy.


Assuntos
Organização do Financiamento/organização & administração , Obtenção de Fundos/organização & administração , Liderança , Eficiência Organizacional , Estados Unidos
18.
Rapid Commun Mass Spectrom ; 22(10): 1528-32, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18421699

RESUMO

Leonardite and Elliot soil humic acids have been analyzed by laser desorption ionization mass spectrometry (LDI MS) in the m/z 4000-200,000 range. Positive ion mass spectra for each humic acid obtained under optimum conditions showed a broad high-mass distribution between m/z 20,000 and 80,000. The dependence of the mass distribution on instrumental parameters and solution conditions was used to investigate the nature of the high-mass peaks from humic acid spectra. Our data suggests that macromolecular ions and humic acid aggregates have the same probability of occurrence while cluster ion formation has a low probability of occurrence.

20.
J Colloid Interface Sci ; 305(1): 57-61, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17045283

RESUMO

The structural examination of the complexes formed between humic acid and cationic surfactants has environmental implications. A humic acid (HA) dissolved in 0.1 M NaOH (5 g/L) was reacted with a cationic surfactant (hexadecyltrimethylammonium bromide or CTAB) at initial solution concentrations of 1, 5, 10, 20, 30, 40 and 50 mM. The HA precipitated at CTAB concentrations of 20, 30, and 50 mM but the complexes were soluble at 40 mM and below 20 mM. The charge neutralization between humic acid anions and CTAB micelles and the subsequent charge reversal due to hydrophobic interactions explain the behavior of the HA-CTAB complexes. The HA solution (5 g/L), reaction products (supernatants and precipitates), and pure cationic surfactant solutions were studied by the small-angle X-ray scattering (SAXS) technique in order to determine the structure of HA-CTAB complexes. The scattering intensity (I(q)) of various HA-CTAB systems were recorded over a range of scattering vectors (q=0.053-4.0 nm(-1)). HA forms networks in an alkaline solution with a characterization length of 7.8 nm or greater. The HA-CTAB precipitates and the 50-mM CTAB solution gave d(100) and d(110) reflections of a hexagonal structure. The hexagonal array of cylindrical CTAB micelles has a lattice parameter of 5.01 nm in pure solution, and the parameter decreases in the order: 4.96, 4.91, and 4.85 nm for the precipitates of HA-CTAB (50, 30, and 20 mM, respectively), indicating that the structure of CTAB micelles was disturbed by the addition of HA. The molecular properties and behavior of HA in solution were discussed.

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