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1.
Drug Test Anal ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38636555

RESUMEN

The Association of Official Racing Chemists (AORC) guidelines for drug testing in animal hair provide animal sport doping control laboratories with a framework for the implementation of a robust and legally defensible program for the analysis, both screening and confirmatory, of animal hair samples. The guidelines were compiled by the AORC Hair Analysis Committee, which is comprised of experts from animal sport doping control laboratories around the world, before being ratified by the AORC membership. They provide guidance on all stages of animal hair analysis, from sample collection, through sample pre-treatment and extraction and onto instrumental analysis.

2.
Drug Test Anal ; 15(3): 361-367, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36354265

RESUMEN

MK-0677 (ibutamoren) is an orally active non-peptide growth hormone secretagogue that binds to the ghrelin receptor stimulating the secretion of endogenous growth hormone. It is one of the most prevalent performance-enhancing compounds currently available online and is potentially subject to abuse both in human and equine sports. The aim of the current study was to investigate whether it could be detected in equine hair following oral administration of MK-0677 mesylate to a Thoroughbred racehorse. MK-0677 and its O-dealkylated metabolite were extracted using an existing method for prohibited substances in equine hair and analysed by liquid chromatography tandem mass spectrometry. This enabled the detection of MK-0677 in all hair samples collected, up to 209 days in mane and 358 days in tail. A follow-up methodology with an extensive wash procedure was carried out for selected hair samples, which unambiguously verified the presence of MK-0677. Wash criteria to differentiate between internal incorporation (via bloodstream) and external deposition (via sweat and sebum) was also assessed and indicated internal incorporation for the samples collected at later time points (≥52 days) and a combination of internal incorporation and external deposition for hair samples collected at the earlier time point (2 days).


Asunto(s)
Cabello , Secretagogos , Humanos , Animales , Caballos , Secretagogos/análisis , Cabello/química , Hormona del Crecimiento , Administración Oral
3.
J Vet Pharmacol Ther ; 45(1): 54-62, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34644412

RESUMEN

Paracetamol is a widely used, non-opioid analgesic and antipyretic drug. Scientific evidence suggests that it is an effective pain treatment in equine medicine. However, there is very little published information about the pharmacokinetics of the drug in the horse. The aim of the research was to determine the pharmacokinetics of paracetamol in equine plasma and urine to inform treatment of Thoroughbred racehorses. In this multi-dose study, paracetamol was administered orally at 20 mg/kg to six Thoroughbred horses. Pre- and post-administration urine and plasma samples were collected and analysed using a quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetic analysis of urine and plasma paracetamol clearance profiles was carried out, which enabled the calculation of possible screening limits (SL) that can regulate for a detection time of 120 h. Additionally, an estimation of orthocetamol concentration levels in urine was carried out to investigate any underlying relationship between the para- and ortho-isomers as both were suspected to contribute to basal levels, possibly due to environmental feed sources.


Asunto(s)
Acetaminofén , Analgésicos no Narcóticos , Administración Oral , Animales , Cromatografía Liquida/veterinaria , Caballos , Espectrometría de Masas en Tándem/veterinaria
4.
Drug Test Anal ; 12(6): 731-742, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32052913

RESUMEN

Animal sport doping control laboratories are constantly reviewing ways in which they can improve their service offering whilst ensuring that they remain economically viable. This paper describes the development and assessment of a rapid and economical method for the detection of intact glucuronide conjugates of three anabolic steroids and their metabolites along with three corticosteroids in canine urine. The analysis of intact drug conjugates for animal sport doping control is generally not performed routinely as it presents a number of analytical challenges, not least of which is the lack of availability of appropriate reference standards. Here, we report the development of a UHPLC-MS/MS method using APCI in the negative ion mode for the detection of intact phase II conjugates, including the importance of in vitro incubations in order to provide appropriate reference materials. Cross-validation of the developed method demonstrated that the detection capability of the intact phase II conjugates of stanozolol, boldenone, nandrolone, and their metabolites along with the corticosteroids dexamethasone and methylprednisolone was equivalent to that achieved in routine race-day screens. The new process has been in operation for approximately 2 years and has been used to analyze in excess of 13500 canine urine samples, resulting in a number of positive screening findings. To the best of our knowledge, this is the first reported use of a routine screen for intact drug conjugates within animal sport doping control.


Asunto(s)
Perros , Doping en los Deportes/métodos , Detección de Abuso de Sustancias/métodos , Corticoesteroides/orina , Anabolizantes/orina , Animales , Cromatografía Líquida de Alta Presión , Glucurónidos/orina , Noretindrona/orina , Estándares de Referencia , Reproducibilidad de los Resultados , Deportes , Esteroides/orina , Espectrometría de Masas en Tándem , Congéneres de la Testosterona
5.
Can J Diet Pract Res ; 72(4): 176, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22146114

RESUMEN

PURPOSE: We assessed principals' perceptions about the level of school nutrition policy (SNP) implementation in Prince Edward Island elementary schools, objectively evaluated how closely elementary schools are following SNP regulations for types and frequency of foods offered at school, and explored principals' beliefs about the key enablers and barriers to SNP implementation. METHODS: Phase I involved a cross-sectional survey of principals' assessment of perceived and actual adherence to SNP components. Phase II included in-depth interviews to explore principals' perceptions about factors influencing policy adherence. Descriptive statistics were generated. Thematic content analysis was used to identify themes. RESULTS: Forty-one (93%) principals participated in Phase I, and nine of these participated in Phase II. The level of implementation of SNP components varied. Seventy-four percent of all foods sold were categorized as allowed by the SNP; 68% of schools sold at least one "not allowed" food. Key barriers included lost revenue, a higher cost of healthy foods, and limited availability of policy-allowed foods. Enablers were a high level of community support, ready access to food suppliers, and active parent volunteers. CONCLUSIONS: While schools are making progress in implementing the SNP, challenges remain. Identifying and communicating strategies for healthy fundraising activities and finding ways to involve parents in SNP implementation are recommended.


Asunto(s)
Servicios de Alimentación , Implementación de Plan de Salud , Política Nutricional , Percepción , Instituciones Académicas/organización & administración , Niño , Promoción de la Salud , Humanos , Isla del Principe Eduardo , Encuestas y Cuestionarios
6.
Psychol Health ; 25(8): 925-41, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20204952

RESUMEN

This paper elicited context specific underlying beliefs for physical activity, fruit and vegetable consumption and smoke-free behaviour from the Theory of Planned Behaviour (TPB), and then determined whether the TPB explained significant variation in intentions and behaviour over a 1 month period in a sample of grade 7-9 (age 12-16 years) adolescents. Eighteen individual interviews and one focus group were used to elicit student beliefs. Analyses of this data produced behavioural, normative and control beliefs which were put into a TPB questionnaire completed by 183 students at time 1 and time 2. The Path analyses from the main study showed that the attitude/intention relationship was moderately large for fruit and vegetable consumption and small to moderate for being smoke free. Perceived behavioural control had a large effect on being smoke free and a moderately large effect for fruit and vegetable consumption and physical activity. Intention had a large direct effect on all three behaviours. Common (e.g. feel better, more energy) and behaviour-specific (e.g., prevent yellow fingers, control my weight) beliefs emerged across the three health behaviours. These novel findings, to the adolescent population, support the importance of specific attention being given to each of the behaviours in future multi-behavioural interventions.


Asunto(s)
Actitud Frente a la Salud , Ejercicio Físico , Conducta Alimentaria , Fumar , Adolescente , Conducta del Adolescente , Canadá , Niño , Femenino , Humanos , Masculino , Modelos Teóricos , Encuestas y Cuestionarios
7.
Steroids ; 75(1): 57-69, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19854209

RESUMEN

In this study, the use of equine liver/lung microsomes and S9 tissue fractions were used to study the metabolism of the androgenic/anabolic steroid stanozolol as an example of the potential of in vitro technologies in sports drug surveillance. In vitro incubates were analysed qualitatively alongside urine samples originating from in vivo stanozolol administrations using LC-MS on a high-resolution accurate mass Thermo Orbitrap Discovery instrument, by LC-MS/MS on an Applied Biosystems Sciex 5500 Q Trap and by GC-MS/MS on an Agilent 7000A. Using high-resolution accurate mass full scan analysis on the Orbitrap, equine liver microsome and S9 in vitro fractions were found to generate all the major phase-1 metabolites observed following in vivo administrations. Additionally, analysis of the liver microsomal incubates using a shallower HPLC gradient combined with various MS/MS functions on the 5500 Q trap allowed the identification of a number of phase 1 metabolites previously unreported in the equine or any other species. Comparison between liver and lung S9 metabolism showed that the liver was the major site of metabolic activity in the equine. Furthermore, using chemical enzyme inhibitors that are known to be selective for particular isoforms in other species suggested that an enzyme related to CYP2C8 may be responsible the production of 16-hydroxy-stanozolol metabolites in the equine. In summary, the in vitro and in vivo phase 1 metabolism results reported herein compare well and demonstrate the potential of in vitro studies to compliment the existing in vivo paradigm and to benefit animal welfare through a reduction and refinement of animal experimentation.


Asunto(s)
Doping en los Deportes , Estanozolol/análisis , Estanozolol/orina , Detección de Abuso de Sustancias/métodos , Anabolizantes/administración & dosificación , Anabolizantes/química , Anabolizantes/metabolismo , Andrógenos/administración & dosificación , Andrógenos/análisis , Andrógenos/metabolismo , Animales , Hidrocarburo de Aril Hidroxilasas/antagonistas & inhibidores , Hidrocarburo de Aril Hidroxilasas/metabolismo , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Caballos , Hidroxitestosteronas/química , Hidroxitestosteronas/metabolismo , Cetoconazol/farmacología , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Estructura Molecular , Quercetina/farmacología , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray , Estanozolol/administración & dosificación
8.
Br J Educ Psychol ; 73(Pt 4): 585-98, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14713379

RESUMEN

BACKGROUND: When constructing stimuli for experimental investigations of cognitive processes in early reading development, researchers have to rely on adult or American children's word frequency counts, as no such counts exist for English children. AIM: The present paper introduces a database of children's early reading vocabulary, for use by researchers and teachers. SAMPLE: Texts from 685 books from reading schemes and story books read by 5-7 year-old children were used in the construction of the database. METHOD: All words from the 685 books were typed or scanned into an Oracle database. RESULTS: The resulting up-to-date word frequency list of early print exposure in the UK is available in two forms from a website address given in this paper. This allows access to one list of the words ordered alphabetically and one list of the words ordered by frequency. We also briefly address some fundamental issues underlying early reading vocabulary (e.g., that it is heavily skewed towards low frequencies). Other characteristics of the vocabulary are then discussed. CONCLUSIONS: We hope the word frequency lists will be of use to researchers seeking to control word frequency, and to teachers interested in the vocabulary to which young children are exposed in their reading material.


Asunto(s)
Periodicidad , Lectura , Vocabulario , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Masculino
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