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1.
Environ Sci Technol ; 56(10): 6078-6090, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35486899

RESUMO

Researchers have developed numerous per- and polyfluoroalkyl substances (PFAS)-free aqueous film-forming foam (AFFF) formulations to replace PFAS-containing AFFF used for fire suppression. As part of the Department of Defense's Strategic Environmental Research and Development Program (SERDP), we examined the direct lethal effects of seven PFAS-free AFFF and a PFAS-containing AFFF on 14 aquatic species using a series of lethal concentration (LC50) tests. We assessed the LC10, LC50, and LC90 values using log-logistic and logit analyses. Across all aquatic species tested, we discovered that exposure to at least one PFAS-free AFFF was more or as toxic as exposure to the PFAS-containing AFFF. For most cases, National Foam Avio F3 Green KHC 3% and Buckeye Platinum Plus C6MILSPEC 3% were the most and least toxic formulations, respectively. Moreover, we found consistency among results from multiple experiments using the same minnow species (Pimephales promelas) and among closely related taxa (e.g., daphnids, amphibians). Lastly, the LC50 values for AFFF formulations trended lower for tested marine species as compared to those of freshwater species. These results dramatically increase the current knowledge on the potentially toxic effects of AFFF but also highlight the need for additional research and the development of new PFAS-free AFFF that are more "ecologically friendly" than those containing persistent PFAS.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Aerossóis , Fluorocarbonos/análise , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
2.
JMIR Public Health Surveill ; 6(2): e19045, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32479413

RESUMO

The coronavirus disease (COVID-19) pandemic has accelerated the telehealth tipping point in the practice of family medicine and primary care in the United States, making telehealth not just a novel approach to care but also a necessary one for public health safety. Social distancing requirements and stay-at-home orders have shifted patient care from face-to-face consultations in primary care offices to virtual care from clinicians' homes or offices, moving to a new frontline, which we call the "frontweb." Our telehealth workgroup employed the Clinical Transformation in Technology implementation framework to accelerate telehealth expansion and to develop a consensus document for clinician recommendations in providing remote virtual care during the pandemic. In a few weeks, telehealth went from under 5% of patient visits to almost 93%, while maintaining high levels of patient satisfaction. In this paper, we share clinician recommendations and guidance gleaned from this transition to the frontweb and offer a systematic approach for ensuring "webside" success.


Assuntos
Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Telemedicina , COVID-19 , Humanos , Estados Unidos/epidemiologia
3.
Nanotoxicology ; 11(9-10): 1127-1139, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29192531

RESUMO

As integration of nanoparticles (NPs) into products becomes more common, the need to address the paucity of chronic hazard information for aquatic environments required to determine risk potential increases. This study generated acute and chronic toxicity reference values for Ceriodaphnia dubia exposed to 20 and 100 nm silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) to generate and evaluate potential differences in acute-to-chronic ratios (ACR) using two different feeding methods. A modified feeding procedure was employed alongside the standard procedures to investigate the influence of food on organism exposure. An 8-h period before food was added allowed direct organism exposure to NP dispersions (and associated ions) without food-to-NP interactions. The AgNPs [chronic lethal median concentrations (LC50) between 18.7 and 31.9 µg/L] were substantially more toxic than AuNPs (LC50 = 21 507 to >26 384 µg/L). The modified chronic testing method resulted in greater sensitivity in AgNPs exposures. However, the modified feeding ration had less of an effect in exposures to the larger (100 nm) AgNPs compared to smaller particles (20 nm). The ACRs for AgNPs using the standard feeding ration were 1.6 and 3.5 for 20 nm and 100 nm, respectively. The ACRs for AgNPs using the modified feeding ration were 3.4 and 7.6 for 20 nm and 100 nm NPs, respectively. This supports that the addition of the standard feeding ration decreases C. dubia chronic sensitivity to AgNPs, although it must also be recognized organisms may be sensitized due to less access to food. The ACRs for 20 nm and 100 nm AuNPs (standard ration only) were 4.0 and 3.0, respectively. It is important to also consider that dissolved Ag+ ions are more toxic than AgNPs, based on both acute toxicity values in the cited literature and chronic toxicity thresholds generated in this study that support existing thresholds that Ag+ are likely protective of AgNPs effects.


Assuntos
Daphnia/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ouro/química , Dose Letal Mediana , Nanopartículas Metálicas/química , Tamanho da Partícula , Prata/química , Propriedades de Superfície , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Poluentes Químicos da Água/química
4.
Nanotoxicology ; 11(4): 546-557, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28463032

RESUMO

The unique behavior of engineered nanomaterials (ENM) in aqueous media and dynamic changes in particle settling, agglomeration and dissolution rates is a challenge to the consistency, reliability and interpretation of standard aquatic hazard bioassay results. While the toxicological endpoints (e.g., survival, growth, reproduction, etc.) in ecotoxicity bioassays are largely applicable to ENMs, the standard methods as written for dissolved substances are confounded by the dynamic settling, agglomeration and dissolution of particulate ENMs during the bioassay. A testing framework was designed to serve as a starting point to identify approaches for the consistent conduct of aquatic hazard tests that account for the behavior of ENMs in test media and suitable data collection to support representative exposure metrology. The framework was demonstrated by conducting three case studies testing ENMs with functionally distinct characteristics and behaviors. Pretests with a temporal sampling of particle concentration, agglomeration and dissolution were conducted on each ENM in test media. Results indicated that a silver nanoparticle (AgNP) powder was not dispersible, a nano-TiO2 powder was dispersible but unstable, and a polyvinylpyrrolidinone-coated AgNP was relatively stable in test media. Based on these functional results, Ceriodaphnia dubia bioassays were conducted to compare different exposure summary methods (nominal, arithmetic average, geometric average, time-weighted average) for calculating and expressing toxicity endpoints. Results indicated that while arithmetic means were effective for expressing the toxicity of more stable materials, time-weighted averaged concentrations were appropriate for the unstable nano-TiO2.


Assuntos
Daphnia/efeitos dos fármacos , Ecotoxicologia/métodos , Nanopartículas/toxicidade , Prata/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Reprodutibilidade dos Testes , Solubilidade , Testes de Toxicidade/métodos
5.
Environ Toxicol Chem ; 36(1): 89-95, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27207187

RESUMO

Ammonia is an important contaminant to consider in all toxicity tests. It is especially important to consider the impacts of ammonia in test methods that use sensitive water column organisms exposed to sediments or sediment extracts, such as porewater and elutriate toxicity tests. Embryo-larval development toxicity tests, such as the 48-h method using Mytilus mussel species, are particularly sensitive to ammonia. To better understand the effect thresholds across different life stages of these mussels, 6 short-term (48-h) development toxicity tests and 3 21-d toxicity tests with different-sized juvenile mussels were conducted. Two of the juvenile mussel tests involved 21-d continuous chronic exposure to ammonia, whereas the third involved an acute 2-d ammonia exposure, followed by a 19-d recovery period. The embryo-larval development test method (50% effect concentration [EC50] = 0.14-0.18 mg/L un-ionized ammonia) was 2.5 times more sensitive than the juvenile mussel 21-d survival endpoint (50% lethal concentration = 0.39 mg/L un-ionized ammonia) and 2 times more sensitive than the most sensitive sublethal juvenile mussel endpoint (EC50 = 0.26 mg/L un-ionized ammonia). Further, it was found that the juveniles recovered from a 48-h exposure to un-ionized ammonia of up to 1.1 mg/L. The data generated suggest that the embryo development endpoint was sufficiently sensitive to un-ionized ammonia to protect the chronically exposed (21 d) juvenile mussels. Environ Toxicol Chem 2017;36:89-95. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.


Assuntos
Amônia/toxicidade , Mytilus edulis/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Embrião não Mamífero/efeitos dos fármacos , Sedimentos Geológicos/química , Larva , Mytilus edulis/crescimento & desenvolvimento , Testes de Toxicidade
6.
Environ Toxicol Chem ; 35(7): 1835-42, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26666709

RESUMO

An initiative within the US military is targeting the replacement of traditional munitions constituents with insensitive munitions to reduce the risk of accidental detonation. The bioavailability and bioaccumulative potential of the insensitive munitions compound 2,4-dinitroanisole (DNAN) to Eisenia fetida was assessed in soils with different geochemical characteristics. Prior to exposure, soils were chemically spiked with DNAN and aged for 1 wk or 29 wk. Transformation products 2- and 4-amino-nitroanisole (2A-4NAN and 4A-2NAN) occurred in aged soils and their porewater but never at concentrations higher than the residual DNAN. The sum of DNAN, 2A-4NAN, and 4A-2NAN (sumDNAN) in soil decreased with aging, likely by irreversible binding. Both clay and organic matter contents of the soil appeared to affect the bioavailability of DNAN. The sumDNAN body residues of earthworms approached apparent steady state after 1 d and remained relatively constant through to day 7. Higher concentrations of 2A-4NAN and 4A-2NAN measured in worm tissues relative to those in soil suggest reductive transformation of DNAN in the tissues. Mean bioaccumulation factors (ratio of tissue to soil concentrations) varied from 1.2 to 4.3, whereas mean bioconcentration factors (ratio of tissue to porewater concentrations) ranged from 1.4 to 3.2. Porewater seems to play a significant role in the accumulation of DNAN in earthworms, consistent with equilibrium partitioning theory. The concentration of DNAN in soil porewater could serve as an indicator of bioavailability as well as a predictor of the concentration of that compound in earthworms. Environ Toxicol Chem 2016;35:1835-1842. Publlished 2015 SETAC. This article is a US Government work, and as such, is in the public domain in the United States of America.


Assuntos
Anisóis/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Animais , Anisóis/análise , Anisóis/toxicidade , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Trato Gastrointestinal/química , Trato Gastrointestinal/metabolismo , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
7.
Augment Altern Commun ; 30(4): 298-313, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25384797

RESUMO

Graphic symbols are a necessity for pre-literate children who use aided augmentative and alternative communication (AAC) systems (including non-electronic communication boards and speech generating devices), as well as for mobile technologies using AAC applications. Recently, developers of the Autism Language Program (ALP) Animated Graphics Set have added environmental sounds to animated symbols representing verbs in an attempt to enhance their iconicity. The purpose of this study was to examine the effects of environmental sounds (added to animated graphic symbols representing verbs) in terms of naming. Participants included 46 children with typical development between the ages of 3;0 to 3;11 (years;months). The participants were randomly allocated to a condition of symbols with environmental sounds or a condition without environmental sounds. Results indicated that environmental sounds significantly enhanced the naming accuracy of animated symbols for verbs. Implications in terms of symbol selection, symbol refinement, and future symbol development will be discussed.


Assuntos
Estimulação Acústica/métodos , Reconhecimento Visual de Modelos , Estimulação Luminosa/métodos , Vocabulário , Pré-Escolar , Auxiliares de Comunicação para Pessoas com Deficiência , Feminino , Humanos , Masculino , Reconhecimento Fisiológico de Modelo
8.
J Speech Lang Hear Res ; 57(5): 1779-91, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24811580

RESUMO

PURPOSE: The effects of animation on naming and identification of graphic symbols for verbs and prepositions were studied in 2 graphic symbol sets in preschoolers. METHOD: Using a 2 × 2 × 2 × 3 completely randomized block design, preschoolers across three age groups were randomly assigned to combinations of symbol set (Autism Language Program [ALP] Animated Graphics or Picture Communication Symbols [PCS]), symbol format (animated or static), and word class (verbs or prepositions). Children were asked to name symbols and to identify a target symbol from an array given the spoken label. RESULTS: Animated symbols were more readily named than static symbols, although this was more pronounced for verbs than for prepositions. ALP symbols were named more accurately than PCS in particular with prepositions. Animation did not facilitate identification. ALP symbols for prepositions were identified better than PCS, but there was no difference for verbs. Finally, older children guessed and identified symbols more effectively than younger children. CONCLUSIONS: Animation improves the naming of graphic symbols for verbs. For prepositions, ALP symbols are named more accurately and are more readily identifiable than PCS. Naming and identifying symbols are learned skills that develop over time. Limitations and future research directions are discussed.


Assuntos
Idioma , Filmes Cinematográficos , Vocabulário , Pré-Escolar , Feminino , Humanos , Testes de Linguagem , Masculino , Nomes , Simbolismo
9.
Environ Toxicol Chem ; 33(8): 1783-91, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24753094

RESUMO

Assessing the dissolution of silver nanoparticles (AgNPs) in laboratory test media and in the aquatic environment is critical for determining toxicity. In the present study, the ion-release kinetics for 20-nm, 50-nm, and 80-nm AgNPs in environmentally relevant freshwaters with different electrical conductivity values (30 µS/cm, 150 µS/cm) were examined and related to the associated impact on Daphnia magna. The acute toxicity of the AgNP suspensions to D. magna was assessed after 0 d and 7 d of interaction time between the particles and test media. When 48-h lethal median concentrations were expressed as total silver, D. magna was more sensitive to AgNPs suspended in low ionic strength media relative to higher ionic strength media, with the exception of 50-nm AgNPs suspended in the 150-µS/cm medium. A 3.3-fold increase in hydrodynamic diameter measured by dynamic light scattering and field flow fractionation was observed over time for 20-nm particles in the 150-µS/cm medium, but only a small increase in aggregation size for 50-nm and 80-nm particles (1.4-fold and 1.2-fold increase, respectively) was observed. At a lower conductivity of 30 µS/cm, a 1.7-fold, 1.0-fold, and 1.2-fold increase in aggregation size was observed in the 20-nm, 50-nm, and 80-nm particles, respectively. Thus, the impact of higher conductivity test media on increased aggregation and decreased toxicity (after 7 d) was relatively greater for the smaller (20-nm) AgNP higher compared to the 50-80 nm AgNPs.


Assuntos
Ecotoxicologia , Água Doce/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Prata/química , Prata/toxicidade , Animais , Daphnia/efeitos dos fármacos , Fracionamento por Campo e Fluxo , Cinética , Concentração Osmolar , Tamanho da Partícula , Solubilidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
10.
Environ Toxicol Chem ; 32(9): 2069-77, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23686570

RESUMO

As the production and applications of silver nanoparticles (AgNPs) increase, it is essential to characterize fate and effects in environmental systems. Nanosilver materials may settle from suspension; therefore, the authors' objective was to utilize environmentally relevant bioassays and study the impact, bioaccumulation, tissue distribution, uptake, and depuration of AgNPs on a sediment-dwelling invertebrate, Lumbriculus variegatus. Hydrodynamic diameters of uncoated 30-nm, 80-nm, and 1500-nm AgNP powders and a polyvinyl pyrrolidone (PVP) AgNP suspension were measured utilizing dynamic light scattering in freshwater media (0-280 µS/cm). Aggregation for 30 nm, 80 nm, and 1500 nm silver increased with conductivity but was minimal for PVP silver. Lumbriculus variegatus were exposed to AgNPs or silver nitrate (AgNO3 ) spiked into sediment (nominally 100 mg/kg) and water (PVP 30 nm and 70 nm Ag, nominally 5 mg/L). Uptake was assessed through inductively coupled plasma mass spectroscopy (ICP-MS) and hyperspectral imaging. Particle sizes were examined through field flow fractionation-ICP-MS (FFF-ICP-MS) and ICP-MS in single particle mode (SP-ICP-MS). Lumbriculus variegatus were also depurated for 6 h, 8 h, 24 h, and 48 h to determine gut clearance. Bioaccumulation factors of sediment-exposed L. variegatus were similar regardless of particle size or coatings. The FFF-ICP-MS and SP-ICP-MS detected AgNPs for up to 48 h post depuration. The present study provides information on bioaccumulation and interactions of AgNPs within biological systems.


Assuntos
Nanopartículas Metálicas , Oligoquetos/efeitos dos fármacos , Prata/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Disponibilidade Biológica , Água Doce , Sedimentos Geológicos/química , Oligoquetos/metabolismo , Tamanho da Partícula , Povidona/química , Prata/química , Nitrato de Prata/metabolismo , Distribuição Tecidual , Poluentes Químicos da Água/química
11.
J Spinal Cord Med ; 32(3): 336-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19810635

RESUMO

CONTEXT: Social work and case management (SW/CM) are integral components of acute inpatient spinal cord injury (SCI) rehabilitation. However, evidence is sparse regarding the impact of SW/CM interventions on outcomes. To advance research on SW/CM clinical practice in SCI rehabilitation, SW/CM providers and researchers first must have standard classifications for SW/CM interventions. BACKGROUND/OBJECTIVE: To develop a taxonomy (classification) of the various interventions and services that comprise SW/CM. METHODS: A group of SW/CM clinicians compiled a list of activities performed as routine practice at the participating rehabilitation facilities. These activities were grouped and defined systematically. RESULTS: The resulting taxonomy includes 8 major activity topics (financial planning, discharge planning, discharge services, supportive counseling, information about and referral to peer/advocacy groups, education about SCI and other relevant topics, information about and referral to community/in-house services, and team conferences), which were further stratified into specific content areas. Interactions with the patient, family, or other team members and resources, along with descriptions of the interactions that are applicable to each of the 8 activity topics, were included as well. CONCLUSION: An intervention taxonomy is required to study the SW/CM interventions and the potential association with positive rehabilitation outcomes for patients with SCI. The SW/CM taxonomy developed for the SCIRehab project, which will be used with 1,500 patients admitted to 6 SCIRehab centers over 2.5 years, will provide an infrastructure for such research.


Assuntos
Administração de Caso/classificação , Classificação , Serviço Social/classificação , Serviço Social/métodos , Traumatismos da Medula Espinal/reabilitação , Serviços de Assistência Domiciliar , Humanos , Garantia da Qualidade dos Cuidados de Saúde
12.
Am J Physiol Endocrinol Metab ; 285(3): E584-91, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12900380

RESUMO

Both insulin and glucagon stimulate steady-state levels of Sp1 transcription factor, but only insulin stimulates transcription of the calmodulin (CaM) gene in liver. Because O-glycosylation of Sp1 by O-linked N-acetylglucosamine (O-GlcNAc) is thought to regulate its ability to activate transcription, we assayed the levels of Sp1 with anti-Sp1 and anti-O-GlcNAc antibodies in Western blots by use of extracts of H-411E liver cells treated with insulin (10,000 microU/ml) or glucagon (1.5 x 10(-5) M). We also assessed subcellular localization of the native and glycosylated Sp1 in H411E cells treated with either hormone in the presence of deoxynorleucine (DON, an indirect inhibitor of O-glycosylation) or streptozotocin (STZ, an indirect stimulator of O-glycosylation). Insulin stimulated both total and O-GlcNAc-modified Sp1 primarily in the nucleus and induced CaM gene transcription (P < 0.0001). In contrast, glucagon promoted accumulation of Sp1 in the cytoplasm but not the nucleus, without significantly stimulating (P = not significant) either its O-glycosylation or transcription of the CaM gene. DON inhibited O-glycosylation of Sp1 and its ability to migrate to the nucleus and transactivate CaM gene transcription. In contrast, cotreatment of cells with STZ and glucagon enhanced O-glycosylation of Sp1, promoting its migration to the nucleus and resulting in increased CaM gene transcription. Thus O-glycosylation of Sp1 by insulin, but not glucagon, apparently enhances its (Sp1) nuclear recruitment and results in activation of CaM gene transcription.


Assuntos
Calmodulina/genética , Fármacos Gastrointestinais/farmacologia , Glucagon/farmacologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Fator de Transcrição Sp1/metabolismo , Acetilglucosamina/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Carcinoma Hepatocelular , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Glucagon/metabolismo , Glicosilação , Hipoglicemiantes/metabolismo , Imuno-Histoquímica , Insulina/metabolismo , Norleucina/análogos & derivados , Norleucina/farmacologia , RNA Mensageiro/análise , Ratos , Estreptozocina/farmacologia , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
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