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1.
Arch Sex Behav ; 47(5): 1321, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29532269

RESUMEN

The term "body eudysmorphia" in the 6th paragraph of this Letter to the Editor incorrectly read "body dysmorphia" in the letter as originally published. The original article has been corrected.

2.
Environ Sci Technol ; 47(3): 1306-12, 2013 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-23305514

RESUMEN

Aquatic organisms are exposed to many toxic chemicals and interpreting the cause and effect relationships between occurrence and impairment is difficult. Toxicity Identification Evaluation (TIE) provides a systematic approach for identifying responsible toxicants. TIE relies on relatively uninformative and potentially insensitive toxicological end points. Gene expression analysis may provide needed sensitivity and specificity aiding in the identification of primary toxicants. The current work aims to determine the added benefit of integrating gene expression end points into the TIE process. A cDNA library and a custom microarray were constructed for the marine amphipod Ampelisca abdita. Phase 1 TIEs were conducted using 10% and 40% dilutions of acutely toxic sediment. Gene expression was monitored in survivors and controls. An expression-based classifier was developed and evaluated against control organisms, organisms exposed to low or medium toxicity diluted sediment, and chemically selective manipulations of highly toxic sediment. The expression-based classifier correctly identified organisms exposed to toxic sediment even when little mortality was observed, suggesting enhanced sensitivity of the TIE process. The ability of the expression-based end point to correctly identify toxic sediment was lost concomitantly with acute toxicity when organic contaminants were removed. Taken together, this suggests that gene expression enhances the performance of the TIE process.


Asunto(s)
Anfípodos/genética , Organismos Acuáticos/genética , Determinación de Punto Final , Genoma/genética , Pruebas de Toxicidad , Contaminantes Químicos del Agua/toxicidad , Anfípodos/efectos de los fármacos , Animales , Organismos Acuáticos/efectos de los fármacos , Biomarcadores/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Sedimentos Geológicos/química , Rhode Island , Ríos/química
4.
Mar Pollut Bull ; 192: 115073, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37245322

RESUMEN

A common method for characterizing microplastics (MPs) involves capturing the plastic particles on a filter after extraction and isolation from the sediment particles. Microplastics captured on the filter are then scanned with Raman spectroscopy for polymer identification and quantification. However, scanning the whole filter manually using Raman analysis is a labor-intensive and time-consuming process. This study investigates a subsampling method for Raman spectroscopic analysis of microplastics (operationally defined here as 45-1000 µm in size) present in sediments and isolated onto laboratory filters. The method was evaluated using spiked MPs in deionized water and two environmentally contaminated sediments. Based on statistical analyses, we found quantification of a sub-fraction of 12.5 % of the filter in a wedge form was optimal, efficient, and accurate for estimating the entire filter count. The extrapolation method was then used to assess microplastic contamination in sediments from different marine regions of the United States.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Plásticos/análisis , Espectrometría Raman , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química
6.
Ecotoxicol Environ Saf ; 73(4): 486-90, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20022112

RESUMEN

The effects of PAHs on fish have been described in the literature, but the ability to assess risk to juvenile and adult fish from exposure to PAHs the field is currently hindered by the lack of a predictive dose-response exposure model. The goal of this paper is to present a framework that can be used to convert concentrations of PAHs in environmental media (e.g., water, food, and sediment) to a dose metric that is predictive of adverse effects. Examples of toxicity studies that can be considered within the framework are presented. Additional toxicity studies are needed to establish the potency and range of toxic responses to mixtures of PAHs that fish encounter in the environment.


Asunto(s)
Peces/crecimiento & desarrollo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Peces/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Contaminantes Químicos del Agua/metabolismo
7.
Mar Environ Res ; 68(3): 118-27, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19481793

RESUMEN

Sediment toxicity tests are valuable tools for assessing the potential effects of contaminated sediments in dredged material evaluations because they inherently address complexity (e.g., unknown contaminants, mixtures, bioavailability). Although there is a need to understand the chronic and sublethal impacts of contaminants, it is common to conduct only short-term lethality tests in evaluations of marine sediments. Chronic toxicity methods for marine sediments have been developed but the efficacy of these methods is less documented. In this evaluation of marine sediments collected from the New York/New Jersey (NY/NJ) Harbor, three 10-d acute toxicity test methods (Ampelisca abdita, Leptocheirus plumulosus, Americamysis bahia) and three chronic and sublethal test methods (28-d L. plumulosus, 20- and 28-d Neanthes arenaceodentata) were applied by three testing laboratories. Although the N. arenaceodentata and A. bahia tests did not indicate significant toxicity for the sediments tested in this study, these methods have been reported useful in evaluating other sediments. The 10-d A. abdita, 10-d L. plumulosus and 28-d L. plumulosus tests were comparable between laboratories, indicating 29-43%, 29%, and 43-71% of the tested sediments as potentially toxic. The 28-d L. plumulosus method was the only chronic toxicity test that responded to the test sediments in this study. The 28-d L. plumulosus endpoint magnitudes were related to sediment chemistry and the sublethal endpoints were reduced as much or more than acute lethality endpoints. However, intra-treatment sublethal endpoint variability was greater, compromising detection of statistical significance. In this study, the chronic L. plumulosus test method was less consistent among laboratories relative to acute test methods, identifying potential for toxicity in a similar number (or slightly more) NY/NJ Harbor sediments.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Pruebas de Toxicidad/métodos , Contaminantes Químicos del Agua/toxicidad , Anfípodos/efectos de los fármacos , Animales , Poliquetos/efectos de los fármacos , Pruebas de Toxicidad/normas
8.
BJU Int ; 99(4): 864-9, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17378847

RESUMEN

OBJECTIVE: To map the fine-touch pressure thresholds of the adult penis in circumcised and uncircumcised men, and to compare the two populations. SUBJECTS AND METHODS: Adult male volunteers with no history of penile pathology or diabetes were evaluated with a Semmes-Weinstein monofilament touch-test to map the fine-touch pressure thresholds of the penis. Circumcised and uncircumcised men were compared using mixed models for repeated data, controlling for age, type of underwear worn, time since last ejaculation, ethnicity, country of birth, and level of education. RESULTS: The glans of the uncircumcised men had significantly lower mean (sem) pressure thresholds than that of the circumcised men, at 0.161 (0.078) g (P = 0.040) when controlled for age, location of measurement, type of underwear worn, and ethnicity. There were significant differences in pressure thresholds by location on the penis (P < 0.001). The most sensitive location on the circumcised penis was the circumcision scar on the ventral surface. Five locations on the uncircumcised penis that are routinely removed at circumcision had lower pressure thresholds than the ventral scar of the circumcised penis. CONCLUSIONS: The glans of the circumcised penis is less sensitive to fine touch than the glans of the uncircumcised penis. The transitional region from the external to the internal prepuce is the most sensitive region of the uncircumcised penis and more sensitive than the most sensitive region of the circumcised penis. Circumcision ablates the most sensitive parts of the penis.


Asunto(s)
Circuncisión Masculina , Pene/inervación , Sensación/fisiología , Adulto , Prepucio/inervación , Prepucio/cirugía , Humanos , Masculino , Pene/cirugía , Umbral Sensorial/fisiología , Tacto/fisiología
9.
Integr Environ Assess Manag ; 1(2): 142-51, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16639896

RESUMEN

Tissue residue-based toxicity benchmarks (TRBs) have typically been developed using the results of individual studies selected from the literature. In the past, TRBs have been developed using a point estimate (e.g., LC50 value) reported in a study on a single species deemed to be most closely related to the receptor of interest. Despite attempts to maximize the protectiveness and relevance of TRBs, their relationship to specific receptors remains uncertain, and their general applicability for use in broader ecological risk assessment contexts is limited. This article proposes a novel framework that establishes benchmarks as distributions rather than single-point estimates. Benchmark distributions allow the user to select a tissue concentration that is associated with the protection of a specific percentage of organisms, rather than linked to a specific receptor. A methodology is proposed for searching, reviewing, and analyzing linked, tissue residue effect data to derive benchmark distributions. The approach is demonstrated for contaminants having a dioxin-like mechanism of toxic action and is based on residue effects data for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and equivalents in early life stage fish. The calculated tissue residue benchmarks for 2,3,7,8-TCDD toxic equivalency (TEQ) derived from the resulting distribution could range from 0.057- to 0.699-ng TCDD/g lipid depending on the level of protection needed; the lower estimate is protective of 99% of fish species whereas the higher end is protective of 90% of fish species.


Asunto(s)
Benchmarking , Contaminantes Ambientales/farmacocinética , Contaminantes Ambientales/toxicidad , Dibenzodioxinas Policloradas/farmacocinética , Dibenzodioxinas Policloradas/toxicidad , Animales , Contaminantes Ambientales/análisis , Peces , Dosificación Letal Mediana , Modelos Teóricos , Dibenzodioxinas Policloradas/análisis , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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