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1.
Aquat Toxicol ; 227: 105582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32823071

RESUMO

While it is likely that ENPs may occur together with other contaminants in nature, the combined effects of exposure to both ENPs and environmental contaminants are not studied sufficiently. In this study, we investigated the acute and sublethal toxicity of PVP coated silver nanoparticles (AgNP) and ionic silver (Ag+; administered as AgNO3) to the marine copepod Calanus finmarchicus. We further studied effects of single exposures to AgNPs (nominal concentrations: low 15 µg L-1 NPL, high 150 µg L-1 NPH) or Ag+ (60 µg L-1), and effects of co-exposure to AgNPs, Ag+ and the water-soluble fraction (WSF; 100 µg L-1) of a crude oil (AgNP + WSF; Ag++WSF). The gene expression and the activity of antioxidant defense enzymes SOD, CAT and GST, as well as the gene expression of HSP90 and CYP330A1 were determined as sublethal endpoints. Results show that Ag+ was more acutely toxic compared to AgNPs, with 96 h LC50 concentrations of 403 µg L-1 for AgNPs, and 147 µg L-1 for Ag+. Organismal uptake of Ag following exposure was similar for AgNP and Ag+, and was not significantly different when co-exposed to WSF. Exposure to AgNPs alone caused increases in gene expressions of GST and SOD, whereas WSF exposure caused an induction in SOD. Responses in enzyme activities were generally low, with significant effects observed only on SOD activity in NPL and WSF exposures and on GST activity in NPL and NPH exposures. Combined AgNP and WSF exposures caused slightly altered responses in expression of SOD, GST and CYP330A1 genes compared to the single exposures of either AgNPs or WSF. However, there was no clear pattern of cumulative effects caused by co-exposures of AgNPs and WSF. The present study indicates that the exposure to AgNPs, Ag+, and to a lesser degree WSF cause an oxidative stress response in C. finmarchicus, which was slightly, but mostly not significantly altered in combined exposures. This indicated that the combined effects between Ag and WSF are relatively limited, at least with regard to oxidative stress.


Assuntos
Copépodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Petróleo/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Copépodes/genética , Copépodes/metabolismo , Interações Medicamentosas , Expressão Gênica/efeitos dos fármacos , Íons , Nanopartículas Metálicas/química , Estresse Oxidativo/genética , Água do Mar/química , Prata/química , Solubilidade , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda , Poluentes Químicos da Água/química
2.
Sci Total Environ ; 511: 469-76, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25574974

RESUMO

Nanoparticles are emerging contaminants of concern. Knowledge on their environmental impacts is scarce, especially on their interactive effects with other contaminants. In this study we investigated effects of titanium dioxide nanoparticles (TiO2NP) on the blue mussel (Mytilus edulis) and determined their influence on the bioavailability and toxicity of benzo(a)pyrene (B(a)P), a carcinogenic polyaromatic hydrocarbon (PAH). Blue mussels were exposed to either TiO2NP (0.2 and 2.0 mg L(-1)) or B(a)P (20 µg L(-1)) and to the respective combinations of these two compounds. Aqueous contaminant concentrations, the uptake of Ti and B(a)P into mussel soft tissue, effects on oxidative stress and chromosomal damage were analyzed. The uncoated TiO2NP agglomerated rapidly in the seawater. The presence of TiO2NP significantly reduced the bioavailability of B(a)P, shown by lowered B(a)P concentrations in exposure tanks and in mussel tissue. The activities of antioxidant enzyme superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were impacted by the various exposure regimes, indicating oxidative stress in the contaminant exposure groups. While SOD activity was increased only in the 0.2TiO2NP exposure group, CAT activity was enhanced in both combined exposure groups. The GPx activity was increased only in the groups exposed to the two single compounds. In hemocytes, increased chromosomal damage was detected in mussels exposed to the single compounds, which was further increased after exposure to the combination of compounds. In this study we show that the presence of TiO2NP in the exposure system reduced B(a)P uptake in blue mussels. However, since most biomarker responses did not decrease despite of the lower B(a)P uptake in combined exposures, the results suggest that TiO2NP can act as additional stressor, or potentially alters B(a)P toxicity by activation.


Assuntos
Benzo(a)pireno/toxicidade , Mytilus edulis/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Benzo(a)pireno/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/química , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Titânio/química , Poluentes Químicos da Água/metabolismo
3.
J Am Med Inform Assoc ; 4(2 Suppl): S73-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9067890

RESUMO

The eighth annual workshop of the IAIMS Consortium was devoted to exploring how information technology might provide the tools to allow health care practices to compete in the new health care environment while maintaining independence. The options that were discussed included: optimizing care of the patient in the local setting; reducing practice overhead by improving efficiency and effectiveness; and finding innovative strategies for providing health care and new products.


Assuntos
Sistemas Integrados e Avançados de Gestão da Informação , Administração da Prática Médica/economia , Competição Econômica , Sistemas Integrados e Avançados de Gestão da Informação/economia
4.
J Am Med Inform Assoc ; 3(5): 308-17, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8880678

RESUMO

Vanderbilt University Medical Center is implementing an Integrated Advanced Information Management System (IAIMS) using a fast-track approach. The elapsed time between start-up and completion of implementation will be 7.5 years. The Start-Up and Planning phases of the project are complete. The Implementation phase asks one question: How does an organization create an environment that redirects and coordinates a variety of individual activities so that they come together to provide an IAIMS? Four answers to this question are being tested. First, design resources to be "scalable"--i.e., capable of supporting enterprise-wide use. Second, provide information technology planning activities as ongoing core functions that direct local efforts. Third, design core infrastructure resources to be both reusable and expandable at the local level. Fourth, use milestones to measure progress toward selected endpoints to permit early refinement of plans and strategies.


Assuntos
Sistemas Integrados e Avançados de Gestão da Informação , Centros Médicos Acadêmicos , Desenvolvimento de Programas , Tennessee
5.
Artigo em Inglês | MEDLINE | ID: mdl-8563398

RESUMO

This paper describes the deliverables framework developed by Vanderbilt University Medical Center (VUMC) in its IAIMS planning process. The key deliverables include: visions for the future; mission, goals, and objectives for the information management function; critical functions for IAIMS; categorized projects; priority recommendations; and a straw man project sequence reflecting dependencies. The paper also discusses how the plan will be used and how it interacts with direction-setting for the Medical Center.


Assuntos
Sistemas Integrados e Avançados de Gestão da Informação , Técnicas de Planejamento , Centros Médicos Acadêmicos , Tennessee
6.
Artigo em Inglês | MEDLINE | ID: mdl-8130533

RESUMO

The strategic planning process that is part of Vanderbilt University's fast track to IAIMS is evolving based on feedback from the process itself. Led by a committee of VUMC's top management, broad-based sub-committees for administration, education, patient care, and research worked initially on the following strategic issues: identifying key external pressures that constrain and provide opportunities, visioning how VUMC might operate in the future, and establishing a mission and high-level goals for information management. Next steps include identifying the critical mass of function that will prompt daily use of the IAIMS by everyone at VUMC and adding groups to focus on information and technology architectures and developing academic informatics. This manuscript gives detailed, practical information about the evolution of the planning process, committees' responsibilities, working relationships, and lessons learned.


Assuntos
Centros Médicos Acadêmicos/organização & administração , Sistemas Integrados e Avançados de Gestão da Informação/organização & administração , Planejamento em Saúde , Política Organizacional , Formulação de Políticas , Tennessee
7.
J Exp Biol ; 169: 1-18, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1328457

RESUMO

This study deals with the effects of chemical pollutants on the transmembrane potential difference for sodium (delta mu Na) in smooth muscle cells of Mytilus edulis. A method for indirect determination of extracellular space, intracellular ion concentrations and delta mu Na has been developed and is applied in the investigations. The determination is based on concentration data from haemolymph and muscle tissue samples. The precision of the method used was tested by direct measurements of the apparent intracellular concentration of sodium and the membrane potential. On the basis of these tests, the method was evaluated as reasonably good. The method was used to study the sensitivity of the transmembrane delta mu Na in Mytilus edulis to 96 h exposures to various sublethal concentrations of formaldehyde, methanol and mercury. Both formaldehyde and mercury induced a depression of delta mu Na. The observed depressions could be ascribed to a change in both the electrogenic and the chemical components of delta mu Na. A depression of delta mu Na was associated with subsequent clinical injury and death. Methanol did not cause death or any changes in delta mu Na. Because of the observed correlation between depression of delta mu Na and clinical injury, delta mu Na is suggested to have a potential as an indicator of toxicity.


Assuntos
Bivalves/fisiologia , Poluentes Ambientais/farmacologia , Músculos/fisiologia , ATPase Trocadora de Sódio-Potássio/efeitos dos fármacos , Sódio/metabolismo , Animais , Poluentes Ambientais/toxicidade , Formaldeído/farmacologia , Formaldeído/toxicidade , Potenciais da Membrana/efeitos dos fármacos , Mercúrio/farmacologia , Mercúrio/toxicidade , Metanol/farmacologia , Metanol/toxicidade , ATPase Trocadora de Sódio-Potássio/fisiologia
8.
Proc AMIA Symp ; : 371-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9929244

RESUMO

In March of 1997, the National Research Council (NRC) of the National Academy of Sciences issued the report, "For the Record: Protecting Electronic Health Information." In its report, the Council recommended both technical and organizational practices to protect electronic health information. At the time the report was issued, Vanderbilt University Medical Center was deeply immersed in the development of organizational practices consistent with the Council's recommendations. We agreed that the recommended technical and organizational practices are important for protecting other information types in addition to health information, and that they suggest appropriate practices for non-electronic information, as well. In this paper, we focus on our process for developing and implementing the seven organizational practices recommended for immediate implementation.


Assuntos
Segurança Computacional , Confidencialidade , Sistemas Integrados e Avançados de Gestão da Informação/organização & administração , Política Organizacional , Formulação de Políticas , Centros Médicos Acadêmicos/organização & administração , Sistemas Integrados e Avançados de Gestão da Informação/normas , Auditoria Médica , Tennessee
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