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1.
Crit Rev Toxicol ; 47(3): 225-262, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27648750

RESUMEN

Little consistency exists in the methodology for toxicological testing of aerosolized nanoparticles used in in vitro, air-interfaced culture (AIC) exposure systems for engineered nanoparticles (ENPs) risk-assessment, preventing inter-laboratory comparisons to identify dose thresholds for adverse effects. These inconsistencies result from heterogeneity in particle types, exposure durations, exposure systems, and dose metrics reported. We screened 10,241 studies in the literature for toxicological assessment of ENPs, resulting in 110 publications included after meeting eligibility criteria. In this review, we critically analyzed methodology within these studies to answer whether: (1) the administered dose or the deposited dose correlated better with biological response, (2) a difference existed between various AIC exposure systems when depositing the same dose, (3) consistent results were generated for nanomaterials with similar physico-chemical properties, (4) the deposited dose in vitro correlated to the deposited dose in vivo, and (5) AIC studies reliably modeled acute toxicity in vivo. Methods used in delivering, measuring, and reporting ENP aerosol doses in vitro are summarized. Dosimetry and biological response comparisons of AIC, conventional suspensions, and in vivo exposures are discussed through case studies on silver, zinc oxide, titanium dioxide, and multi-walled carbon nanotube exposures. Finally, based on these findings, recommendations are offered for design of future AIC experiments to aid standardization and comparisons of results.


Asunto(s)
Aerosoles/toxicidad , Contaminantes Atmosféricos/toxicidad , Exposición por Inhalación/análisis , Nanopartículas/toxicidad , Pruebas de Toxicidad/métodos , Humanos , Modelos Biológicos , Titanio , Óxido de Zinc
2.
PLoS One ; 12(9): e0184025, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28934243

RESUMEN

BACKGROUND: Very little is known about the proportion of oncology trials that get published, the time it takes to publish them, or the reasons why oncology trials do not get published. METHODS: We analyzed all clinical trials that closed to accrual at our cancer center between 2009-2013. Trials were categorized by study purpose (therapeutic vs. diagnostic), phase (pilot, phase I, II, or III), and sponsor (industrial, cooperative group, institutional, or peer-reviewed). Final publications were identified in MEDLINE and EMBASE by NCT numbers, or by querying the principal investigator. For trials not published, we surveyed the principal investigators to identify the reason for non-publication. FINDINGS: 469 of 809 protocols (58%) had been published by November 2016. The calculated probability of publication 7 years after completing accrual was 70.4%; the calculated median time to publication was 47 months. Only 18.8% of protocols overall were estimated to be published within 2 years from completing accrual. The calculated probability of publication was higher for therapeutic trials than non-therapeutic trials, but there was no difference based on phase or sponsor. Among protocols not published, 45.3% had completed accrual, and among these, a majority had a manuscript in preparation or review, or the trial was still collecting data. Failure to publish due to a pharmaceutical sponsor was rare. 30.6% of unpublished trials had closed for various reasons before completing accrual, usually due to poor accrual or pharmaceutical sponsor issues. INTERPRETATION: Almost 30% of trials were calculated to be unpublished by 7 years after closing to accrual at our institution. Failure to reach accrual goals was an important factor in non-publication. We have devised new institutional policies that identify trials likely not to meet accrual goals and require early closure. We should be able to shorten the time from accrual completion to publication, especially for pilot and phase I trials for which long follow up is not needed.


Asunto(s)
Ensayos Clínicos como Asunto , Oncología Médica , Edición/estadística & datos numéricos , Humanos , Probabilidad , Factores de Tiempo
3.
Methods Mol Biol ; 1570: 301-313, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28238146

RESUMEN

The field of nanomedicine is steadily growing and several nanomedicines are currently approved for clinical use with even more in the pipeline. Yet, while the use of nanotechnology to improve targeted drug delivery to the lungs has received some attention, the use of nanoparticles for inhalation drug delivery has not yet resulted in successful translation to market as compared to intravenous drug delivery. The reasons behind the lack of inhaled nanomedicines approved for clinical use or under preclinical development are unclear, but challenges related to safety are likely to contribute. Although inhalation toxicology studies often begin using animal models, there has been an increase in the development and use of in vitro air-liquid interface (ALI) exposure systems for toxicity testing of engineered nanoparticle aerosols, which will be useful for rapid testing of candidate substances and formulations. This chapter describes an ALI cell exposure assay for measuring toxicological effects, specifically cell viability and oxidative stress, resulting from exposure to aerosols containing nanoparticles.


Asunto(s)
Aerosoles , Sistemas de Liberación de Medicamentos , Nanomedicina , Nanopartículas , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Supervivencia Celular , Células Cultivadas , Composición de Medicamentos , Compuestos Férricos/química , Humanos , L-Lactato Deshidrogenasa/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno
4.
Nanoscale ; 8(8): 4482-5, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26854217

RESUMEN

Secretory phospholipase A2 group IIA (sPLA2-IIA) was examined as a point of care marker for determining disease activity in rheumatoid (RA) and psoriatic (PsA) arthritis. Serum concentration and activity of sPLA2-IIA were measured using in-house antibodies and a novel point of care lateral flow device assay in patients diagnosed with varying severities of RA (n = 30) and PsA (n = 25) and found to correlate strongly with C-reactive protein (CRP). Levels of all markers were elevated in patients with active RA over those with inactive RA as well as both active and inactive PsA, indicating that sPLA2-IIA can be used as an analogue to CRP for RA diagnosis at point of care.


Asunto(s)
Artritis Reumatoide/diagnóstico , Fosfolipasas A2 Grupo II/sangre , Adulto , Anciano , Artritis Psoriásica/diagnóstico , Biomarcadores/sangre , Proteína C-Reactiva , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas en el Punto de Atención
5.
Nanoscale ; 8(23): 11834-9, 2016 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-27228183

RESUMEN

Acute pancreatitis is a relatively common and potentially fatal condition, but the presenting symptoms are non-specific and diagnosis relies largely on the measurement of amylase activity by the hospital clinical laboratory. In this work we develop a point of care test for pancreatitis measuring concentration of secretory phospholipase A2 group IB (sPLA2-IB). Novel antibodies for sPLA2-IB were raised and used to design an ELISA and a lateral flow device (LFD) for the point of care measurement of sPLA2-IB concentration, which was compared to pancreatic amylase activity, lipase activity, and sPLA2-IB activity in 153 serum samples. 98 of these samples were obtained from the pathology unit of a major hospital and classified retrospectively according to presence or absence of pancreatitis, and the remaining 55 were obtained from commercial sources to serve as high lipase (n = 20), CA19-9 positive (n = 15), and healthy (n = 20) controls. sPLA2-IB concentration correlated well with the serum activity of both amylase and lipase, and performed at least as well as either markers in the differentiation of pancreatitis from controls.


Asunto(s)
Amilasas/sangre , Lipasa/sangre , Pancreatitis/diagnóstico , Fosfolipasas A2/sangre , Sistemas de Atención de Punto , Enfermedad Aguda , Humanos
6.
Nutrients ; 7(6): 5051-64, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-26110253

RESUMEN

Continuous infusion systems used for enteral nutrition support in the neonatal intensive care unit deliver as little as 60% of the fat in human milk to the neonate. This study determined the effect of mixing common feedings for preterm infants in the feeding bag and tubing on fat losses during enteral feeding. Laboratory models were developed to assess the contribution of various mixing techniques to delivered fat content. Fat content was measured periodically during feeding and compared to baseline measurements. A multistage approach incorporating a feeding bag inverter and a tubing circulation loop delivered >90% of milk fat when used in conjunction with a commercial continuous infusion system. With unfortified human milk, this approach delivered 91.9% ± 1.5% of fat content over a one hour feed, significantly greater (p < 0.01) than 77.5% ± 2.2% delivered by continuous infusion controls (Mean ± SEM). With fortified human milk, this approach delivered 92.1% ± 2.4% of fat content, significantly greater (p < 0.01) than 79.4% ± 1.0% delivered by a non-adapted infusion system (Mean ± SEM). Mixing human milk during continuous infusion improves fat delivery, which may improve nutrition and growth outcomes in low birth weight neonates.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Nutrición Enteral/métodos , Diseño de Equipo , Alimentos Fortificados , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recien Nacido Prematuro/crecimiento & desarrollo , Recién Nacido de muy Bajo Peso/crecimiento & desarrollo , Unidades de Cuidado Intensivo Neonatal , Leche Humana
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