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1.
Environ Sci Technol ; 50(14): 7489-97, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27391856

RESUMO

Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water-air boundary was determined. This is the first report of vapor phase and diffusive flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 6.6 and 210 ng/m(3) and 0.02 and 34 ng/m(3) respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air-water flux of 13 individual PAHs was shown to be at least partially influenced by the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi at nominal rates of 56 000 and 42 000 ng/m(2) day(-1) in the summer. Naphthalene was the PAH with the highest observed volatilization rate of 52 000 ng/m(2) day(-1) in June 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air-water chemical flux determinations with passive sampling technology.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Água
2.
Echocardiography ; 33(10): 1546-1556, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27783876

RESUMO

BACKGROUND: The anatomical substrate for the mid-mural ventricular hyperechogenic zone remains uncertain, but it may represent no more than ultrasound reflected from cardiomyocytes orientated orthogonally to the ultrasonic beam. We sought to ascertain the relationship between the echogenic zone and the orientation of the cardiomyocytes. METHODS: We used 3D echocardiography, diffusion tensor imaging, and microcomputed tomography to analyze the location and orientation of cardiomyocytes within the echogenic zone. RESULTS: We demonstrated that visualization of the echogenic zone is dependent on the position of the transducer and is most clearly seen from the apical window. Diffusion tensor imaging and microcomputed tomography show that the echogenic zone seen from the apical window corresponds to the position of the circumferentially orientated cardiomyocytes. An oblique band seen in the parasternal view relates to cardiomyocytes orientated orthogonally to the ultrasonic beam. CONCLUSIONS: The mid-mural ventricular hyperechogenic zone represents reflected ultrasound from cardiomyocytes aligned orthogonal to the ultrasonic beam. The echogenic zone does not represent a space, a connective tissue sheet, a boundary between ascending and descending limbs of a hypothetical helical ventricular myocardial band, nor an abrupt change in cardiomyocyte orientation.


Assuntos
Ecocardiografia/métodos , Ventrículos do Coração/citologia , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Miócitos Cardíacos/citologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Técnicas de Imagem Cardíaca/métodos , Feminino , Humanos
3.
Environ Sci Technol ; 49(1): 141-9, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25412353

RESUMO

Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during, and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water-air boundary was determined. This is the first report of vapor phase and flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 1 and 24 ng/m(3) and 0.3 and 27 ng/m(3), respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air-water flux of 13 individual PAHs were strongly associated with the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi in the summer, each nominally 10,000 ng/m(2)/day. Acenaphthene was the PAH with the highest observed volatilization rate of 6800 ng/m(2)/day in September 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air-water chemical flux determinations with passive sampling technology.


Assuntos
Poluentes Atmosféricos/análise , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Poluentes Atmosféricos/química , Alabama , Monitoramento Ambiental , Mississippi , Oxigênio/química , Hidrocarbonetos Policíclicos Aromáticos/química , Estações do Ano , Sudeste dos Estados Unidos , Volatilização , Água , Poluentes Químicos da Água/química
4.
Cult Health Sex ; 17(7): 825-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25686777

RESUMO

Using a socio-ecological, structural determinants framework, this study assesses the impact of municipal licensing policies and related policing practices across the Greater Vancouver Area (Canada) on the risk of violence within indoor sex work venues. Qualitative interviews were conducted with 46 migrant/immigrant sex workers, managers and owners of licensed indoor sex work establishments and micro-brothels. Findings indicate that policing practices and licensing requirements increase sex workers' risk of violence and conflict with clients and result in heightened stress, an inability to rely on police support, lost income and the displacement of sex workers to more hidden informal work venues. Prohibitive licensing and policing practices prevent sex workers, managers and owners from adopting safer workplace measures and exacerbate health and safety risks for sex workers. This study provides critical evidence of the negative public health implications of prohibitive municipal licensing in the context of a criminalised and enforcement-based approach to sex work. Workplace safety recommendations include the decriminalisation of sex work and the elimination of disproportionately high fees for licences, criminal record restrictions, door lock restrictions, employee registration requirements and the use of police as licensing inspectors.


Assuntos
Comportamento de Redução do Risco , Delitos Sexuais/estatística & dados numéricos , Profissionais do Sexo/estatística & dados numéricos , Migrantes/estatística & dados numéricos , Violência/prevenção & controle , Adulto , Colúmbia Britânica , Feminino , Humanos , Masculino , Direitos da Mulher/normas , Adulto Jovem
5.
Environ Sci Technol ; 46(4): 2033-9, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22321043

RESUMO

An estimated 4.1 million barrels of oil and 2.1 million gallons of dispersants were released into the Gulf of Mexico during the Deepwater Horizon oil spill. There is a continued need for information about the impacts and long-term effects of the disaster on the Gulf of Mexico. The objectives of this study were to assess bioavailable polycyclic aromatic hydrocarbons (PAHs) in the coastal waters of four Gulf Coast states that were impacted by the spill. For over a year, beginning in May 2010, passive sampling devices were used to monitor the bioavailable concentration of PAHs. Prior to shoreline oiling, baseline data were obtained at all the study sites, allowing for direct before and after comparisons of PAH contamination. Significant increases in bioavailable PAHs were seen following the oil spill, however, preoiling levels were observed at all sites by March 2011. A return to elevated PAH concentrations, accompanied by a chemical fingerprint similar to that observed while the site was being impacted by the spill, was observed in Alabama in summer 2011. Chemical forensic modeling demonstrated that elevated PAH concentrations are associated with distinctive chemical profiles.


Assuntos
Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Golfo do México
6.
Immunol Rev ; 223: 391-421, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18613849

RESUMO

SUMMARY: T-regulatory cells (Tregs) have a fundamental role in the establishment and maintenance of peripheral tolerance. There is now compelling evidence that deficits in the numbers and/or function of different types of Tregs can lead to autoimmunity, allergy, and graft rejection, whereas an over-abundance of Tregs can inhibit anti-tumor and anti-pathogen immunity. Experimental models in mice have demonstrated that manipulating the numbers and/or function of Tregs can decrease pathology in a wide range of contexts, including transplantation, autoimmunity, and cancer, and it is widely assumed that similar approaches will be possible in humans. Research into how Tregs can be manipulated therapeutically in humans is most advanced for two main types of CD4(+) Tregs: forkhead box protein 3 (FOXP3)(+) Tregs and interleukin-10-producing type 1 Tregs (Tr1 cells). The aim of this review is to highlight current information on the characteristics of human FOXP3(+) Tregs and Tr1 cells that make them an attractive therapeutic target. We discuss the progress and limitations that must be overcome to develop methods to enhance Tregs in vivo, expand or induce them in vitro for adoptive transfer, and/or inhibit their function in vivo. Although many technical and theoretical challenges remain, the next decade will see the first clinical trials testing whether Treg-based therapies are effective in humans.


Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Linfócitos T CD4-Positivos/imunologia , Fatores de Transcrição Forkhead/imunologia , Imunoterapia Adotiva , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Tolerância Imunológica , Fatores Imunológicos/uso terapêutico , Ativação Linfocitária , Camundongos
7.
Citiz Sci ; 7(1)2022.
Artigo em Inglês | MEDLINE | ID: mdl-36909292

RESUMO

Disaster research faces significant infrastructure challenges: regional and federal coordination, access to resources, and community collaboration. Disasters can lead to chemical exposures that potentially impact human health and cause concern in affected communities. Community-engaged research, which incorporates local knowledge and voices, is well-suited for work with communities that experience impacts of environmental exposures following disasters. We present three examples of community-engaged disaster research (CEnDR) following oil spills, hurricanes, and wildfires, and their impact on long-term social, physical, and technical community infrastructure. We highlight the following CEnDR structures: researcher/community networks; convenient research tools; adaptable data collection modalities for equitable access; and return of data.

9.
J Allergy Clin Immunol ; 126(6): 1242-51, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21036387

RESUMO

BACKGROUND: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is a primary immunodeficiency with autoimmunity caused by mutations in forkhead box P3 (FOXP3), which encodes a transcription factor involved in regulatory T (Treg) cell function. The mechanistic basis for how different mutations in FOXP3 cause distinct manifestations of IPEX remains unclear. OBJECTIVE: To determine whether 3 different point mutants of FOXP3 that cause severe or mild IPEX differ in their ability to reprogram conventional T cells into Treg cells. METHODS: Human CD4(+) T cells were transduced with wild-type or point mutant forms of FOXP3, and changes in cell surface marker expression, cytokine production, proliferation and suppressive capacity were assessed. Ex vivo T(H)17 cells were also transduced with different forms of FOXP3 to monitor changes in IL-17 production. RESULTS: The forkhead mutant F373A failed to upregulate CD25 and CCR4, did not suppress cytokine production, and induced suppressive activity less effectively than wild-type FOXP3. In contrast, although the forkhead mutant R347H was also defective in upregulation of CD25, it suppressed the production of cytokines, conferred suppressive capacity on CD4(+) T cells, and suppressed IL-17 production. F324L, a mutant outside the forkhead domain associated with mild IPEX, was equivalent to wild-type FOXP3 in all aspects tested. CONCLUSION: Mutations in FOXP3 that cause IPEX do not uniformly abrogate the ability of FOXP3 to regulate transcription and drive the development of Treg cells. These data support the notion that factors in addition to functional changes in Treg cells, such as alterations in conventional T cells, are involved in the pathogenesis of IPEX.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Síndromes de Imunodeficiência/genética , Proteínas Mutantes/metabolismo , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Adolescente , Antígenos CD4/biossíntese , Proliferação de Células , Transdiferenciação Celular/genética , Células Cultivadas , Criança , Citocinas/genética , Citocinas/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/patologia , Síndromes de Imunodeficiência/fisiopatologia , Terapia de Imunossupressão , Proteínas Mutantes/genética , Proteínas Mutantes/imunologia , Mutação Puntual/genética , Poliendocrinopatias Autoimunes , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Transgenes/genética , Adulto Jovem
10.
Aquat Toxicol ; 235: 105810, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33823483

RESUMO

There is a growing awareness that transient, sublethal embryonic exposure to crude oils cause subtle but important forms of delayed toxicity in fish. While the precise mechanisms for this loss of individual fitness are not well understood, they involve the disruption of early cardiogenesis and a subsequent pathological remodeling of the heart much later in juveniles. This developmental cardiotoxicity is attributable, in turn, to the inhibitory actions of crude oil-derived mixtures of polycyclic aromatic compounds (PACs) on specific ion channels and other proteins that collectively drive the rhythmic contractions of heart muscle cells via excitation-contraction coupling. Here we exposed Pacific herring (Clupea pallasi) embryos to oiled gravel effluent yielding ΣPAC concentrations as low as ~ 1 µg/L (64 ng/g in tissues). Upon hatching in clean seawater, and following the depuration of tissue PACs (as evidenced by basal levels of cyp1a gene expression), the ventricles of larval herring hearts showed a concentration-dependent reduction in posterior growth (ballooning). This was followed weeks later in feeding larvae by abnormal trabeculation, or formation of the finger-like projections of interior spongy myocardium, and months later with hypertrophy (overgrowth) of the spongy myocardium in early juveniles. Given that heart muscle cell differentiation and migration are driven by Ca2+-dependent intracellular signaling, the observed disruption of ventricular morphogenesis was likely a secondary (downstream) consequence of reduced calcium cycling and contractility in embryonic cardiomyocytes. We propose defective trabeculation as a promising phenotypic anchor for novel morphometric indicators of latent cardiac injury in oil-exposed herring, including an abnormal persistence of cardiac jelly in the ventricle wall and cardiomyocyte hyperproliferation. At a corresponding molecular level, quantitative expression assays in the present study also support biomarker roles for genes known to be involved in muscle contractility (atp2a2, myl7, myh7), cardiomyocyte precursor fate (nkx2.5) and ventricular trabeculation (nrg2, and hbegfa). Overall, our findings reinforce both proximal and indirect roles for dysregulated intracellular calcium cycling in the canonical fish early life stage crude oil toxicity syndrome. More work on Ca2+-mediated cellular dynamics and transcription in developing cardiomyocytes is needed. Nevertheless, the highly specific actions of ΣPAC mixtures on the heart at low, parts-per-billion tissue concentrations directly contravene classical assumptions of baseline (i.e., non-specific) crude oil toxicity.


Assuntos
Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cardiotoxicidade/patologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/patologia , Peixes/embriologia , Peixes/fisiologia , Coração , Larva , Miocárdio/química , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Água do Mar
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