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1.
Nutrients ; 11(10)2019 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-31591287

RESUMEN

Polyphenols are secondary metabolites involved in a myriad of critical processes in plants. Over recent decades, special attention has been paid to the anti-oxidative role of fruit-derived polyphenols in the human diet, with evidence supporting the contribution of polyphenols in the prevention of numerous non-communicable disease outcomes. However, due to the low concentration in biological fluids in vivo, the antioxidant properties of polyphenols seem to be related to an enhanced endogenous antioxidant capacity induced via signaling through the nuclear respiratory factor 2 pathway. Polyphenols also seem to possess anti-inflammatory and antioxidant properties and have been shown to enhance vascular function via nitric oxide mediated mechanisms. Consequently, there is rationale to support fruit-derived polyphenol supplementation to enhance exercise performance, possibly via improved muscle perfusion. Fruit-derived polyphenol supplementation in exercise studies have included a variety of fruits, e.g., New Zealand blackcurrant, pomegranate, and cherry, in the form of extracts (multicomponent or purified), juices and infusions to varying degrees of benefit. For example, research has yet to link the health-related benefits of black elderberry (Sambucus nigra L.) ingestion to exercise performance in spite of the purported health benefits associated with black elderberry provision in vitro and in vivo models, which has been attributed to their high antioxidant capacity and polyphenol content. This review summarizes the existing evidence supporting a beneficial effect of fruit-derived polyphenols on various biological processes and outlines the potential for black elderberry ingestion to improve nitric oxide production, exercise performance, and the associated physiological responses before-, during- and post-exercise.


Asunto(s)
Suplementos Dietéticos , Ejercicio Físico/fisiología , Frutas/química , Contracción Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Sustancias para Mejorar el Rendimiento/uso terapéutico , Extractos Vegetales/uso terapéutico , Polifenoles/uso terapéutico , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/uso terapéutico , Antioxidantes/aislamiento & purificación , Antioxidantes/uso terapéutico , Suplementos Dietéticos/efectos adversos , Estado de Salud , Humanos , Músculo Esquelético/metabolismo , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Extractos Vegetales/efectos adversos , Extractos Vegetales/aislamiento & purificación , Polifenoles/efectos adversos , Polifenoles/aislamiento & purificación
2.
Molecules ; 23(7)2018 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-29933599

RESUMEN

The objective of this study was to establish a novel method for rapid detection of six glucocorticoids (prednisone, prednisone acetate, prednisolone, hydrocortisone, hydrocortisone acetate, and dexamethasone) added illegally in dietary supplements simultaneously by combining thin layer chromatography (TLC) with spot-concentrated Raman scattering (SCRS). The doping ingredients were separated by TLC, and viewed and located with UV light (254 nm), enriched by chromatography, then Raman spectra were directly detected by a Raman Imagine microscope with 780 nm laser source. This method had complementary advantages of TLC and Raman spectroscopy, which enhanced the specificity of the test results. The limit of detection (LOD) of the reference substances were 4 µg, 4 µg, 4 µg, 6 µg, 6 µg, and 4 µg, respectively. The method was used to study the six glucocorticoids added illegally in five dietary supplements. Fake drugs had been detected. The study showed that the TLC-SCRS method is simple, rapid, specific, sensitive, and reliable. The method could be used for effective separation and detection of six chemical components used in dietary supplement products, and would have good prospects for on-site qualitative screening of dietary supplement products for adulterants.


Asunto(s)
Dexametasona/aislamiento & purificación , Suplementos Dietéticos/análisis , Hidrocortisona/análogos & derivados , Hidrocortisona/aislamiento & purificación , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Prednisolona/aislamiento & purificación , Prednisona/aislamiento & purificación , Cromatografía en Capa Delgada/métodos , Doping en los Deportes/prevención & control , Humanos , Límite de Detección , Espectrometría Raman/métodos
3.
Med Sport Sci ; 62: 68-76, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28571012

RESUMEN

The challenges facing modern anti-doping analytical science are increasingly complex given the expansion of target drug substances, as the pharmaceutical industry introduces more novel therapeutic compounds and the internet offers designer drugs to improve performance. The technical challenges are manifold, including, for example, the need for advanced instrumentation for greater speed of analyses and increased sensitivity, specific techniques capable of distinguishing between endogenous and exogenous metabolites, or biological assays for the detection of peptide hormones or their markers, all of which require an important investment from the laboratories and recruitment of highly specialized scientific personnel. The consequences of introducing sophisticated and complex analytical procedures may result in the future in a change in the strategy applied by the Word Anti-Doping Agency in relation to the introduction and performance of new techniques by the network of accredited anti-doping laboratories.


Asunto(s)
Drogas de Diseño/aislamiento & purificación , Doping en los Deportes/prevención & control , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Detección de Abuso de Sustancias/métodos , Detección de Abuso de Sustancias/tendencias , Acreditación , Anabolizantes/aislamiento & purificación , Humanos , Cooperación Internacional , Laboratorios/normas , Hormonas Peptídicas/aislamiento & purificación
4.
Proteomics Clin Appl ; 10(2): 195-205, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26223570

RESUMEN

PURPOSE: Myostatin is a key regulator of skeletal muscle growth and inhibition of its signaling pathway results in an increased muscle mass and function. The aim of this study was to develop a qualitative detection assay for myostatin-neutralizing antibodies for doping control purposes by using immunological approaches. EXPERIMENTAL DESIGN: To detect different types of myostatin-neutralizing antibodies irrespective of their amino acid sequence, an immunological assay specific for antibodies directed against myostatin and having a human Fc domain was established. Affinity purification and Western blotting strategies were combined to allow extracting and identifying relevant analytes from 200 µL of plasma/serum in a non-targeted approach. The assay was characterized regarding specificity, linearity, precision, robustness, and recovery. RESULTS: The assay was found to be highly specific, robust, and linear from 0.1 to 1 µg/mL. The precision was successfully specified at three different concentrations and the recovery of the affinity purification was 58%. CONCLUSIONS AND CLINICAL RELEVANCE: Within this study, an immunological detection assay for myostatin-neutralizing antibodies present in plasma/serum specimens was developed and successfully characterized. The presented approach can easily be modified to include other therapeutic antibodies and serves as proof-of-concept for the detection of antibody-based myostatin inhibitors in doping control samples.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/aislamiento & purificación , Western Blotting , Doping en los Deportes , Miostatina/antagonistas & inhibidores , Miostatina/inmunología , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Anticuerpos Neutralizantes/inmunología , Cromatografía de Afinidad , Humanos , Sustancias para Mejorar el Rendimiento/inmunología
5.
PLoS One ; 10(1): e0116387, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25617625

RESUMEN

UNLABELLED: The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05). Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS) and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO2max) was not changed by Rg1. However, cycling time to exhaustion at 80% VO2max increased significantly by ~20% (P<0.05). CONCLUSION: Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge.


Asunto(s)
Suplementos Dietéticos , Ejercicio Físico , Ginsenósidos/farmacología , Músculo Esquelético/efectos de los fármacos , Panax/química , Sustancias para Mejorar el Rendimiento/farmacología , Adulto , Método Doble Ciego , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Transportador de Glucosa de Tipo 4/metabolismo , Glucógeno/metabolismo , Humanos , Interleucina-10/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Músculo Esquelético/metabolismo , Sustancias para Mejorar el Rendimiento/química , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Resistencia Física/efectos de los fármacos , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
6.
Sud Med Ekspert ; 56(6): 47-51, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-25474922

RESUMEN

The present review of the literature is focused on the problem of forensic-medical diagnostics of doping cases in sports, with special reference to the main classes of pharmaceutical products forbidden for use by the International Olympic Committee. The main causes of death among the athletes as a result of using doping substances are considered. Much attention is given to adverse reactions induced by long-time intake of anabolic steroids many of which can be identified at autopsy.


Asunto(s)
Anabolizantes/envenenamiento , Doping en los Deportes , Toxicología Forense/métodos , Sustancias para Mejorar el Rendimiento/envenenamiento , Esteroides/envenenamiento , Anabolizantes/aislamiento & purificación , Doping en los Deportes/legislación & jurisprudencia , Toxicología Forense/legislación & jurisprudencia , Humanos , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Intoxicación/diagnóstico , Intoxicación/mortalidad , Esteroides/aislamiento & purificación
7.
Methods ; 56(2): 230-5, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21871962

RESUMEN

For most peptide hormones prohibited in elite sports the concentrations in plasma or urine are very low (pg/mL). Accordingly, hyphenated purification and enrichment steps prior to mass spectrometric detection are required to obtain sufficient doping control assays. Immunoaffinity purification in combination with nano-scale liquid chromatography coupled to high resolution/high accuracy mass spectrometry was found to have the potential of providing the necessary sensitivity and unambiguous specificity to produce reliable results. With the presented methodology 12 prohibited peptides (porcine insulin, Novolog, Apidra, Lantus DesB30-32 metabolite, Humalog and human insulin, Synacthen (synthetic ACTH analogue), luteinizing hormone-releasing hormone (LH-RH), growth hormone releasing hormone (GH-RH(1-29)) and CJC-1295 (GH-RH analogue), LongR(3)-IGF-1 and IFG-1) were simultaneously purified from plasma/serum or urine. With limits of detection for each target compound ranging in the low pg/mL level (urine), the method enables the determination of urinary peptides at physiologically relevant concentrations. For each class of peptides an appropriate antibody and a respective internal standard was implemented ensuring robust analysis conditions. Due to the fast and simple sample preparation procedure (∼25 samples per day) and the fact that all materials are commercial available, the implementation of the methodology to laboratories from other analytical fields (forensics, pharmacokinetic sciences, etc.) is enabled.


Asunto(s)
Cromatografía de Afinidad/métodos , Inmunoensayo/métodos , Hormonas Peptídicas/aislamiento & purificación , Detección de Abuso de Sustancias/métodos , Secuencia de Aminoácidos , Cromatografía de Afinidad/normas , Doping en los Deportes , Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Hormona Liberadora de Hormona del Crecimiento/sangre , Hormona Liberadora de Hormona del Crecimiento/aislamiento & purificación , Hormona Liberadora de Hormona del Crecimiento/orina , Humanos , Inmunoensayo/normas , Insulina Aspart/sangre , Insulina Aspart/orina , Espectrometría de Masas/métodos , Espectrometría de Masas/normas , Datos de Secuencia Molecular , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/orina , Hormonas Peptídicas/sangre , Hormonas Peptídicas/orina , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Sustancias para Mejorar el Rendimiento/orina , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores de Tiempo
8.
Scand J Med Sci Sports ; 21(6): e365-71, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21535184

RESUMEN

The sensitivity of the athlete blood passport to detect blood doping may be improved by the inclusion of total hemoglobin mass (Hb(mass)), but the comparability of Hb(mass) from different laboratories is unknown. To optimize detection sensitivity, the analytical variability associated with Hb(mass) measurement must be minimized. The aim of this study was to investigate the efficacy of using quality controls to minimize the variation in Hb(mass) between laboratories. Three simulated laboratories were set up in one location. Nine participants completed three carbon monoxide (CO) re-breathing tests in each laboratory. One participant completed two CO re-breathing tests in each laboratory. Simultaneously, quality controls containing Low (1-3%) and High (8-11%) concentrations of percent carboxyhemoglobin (%HbCO) were measured to compare hemoximeters in each laboratory. Linear mixed modeling was used to estimate the within-subject variation in Hb(mass), expressed as the coefficient of variation, and to estimate the effect of different laboratories. The analytic variation of Hb(mass) was 2.4% when tests were conducted in different laboratories, which reduced to 1.6% when the model accounted for between-laboratory differences. Adjustment of Hb(mass) values using quality controls achieved a comparable analytic variation of 1.7%. The majority of between-laboratory variation in Hb(mass) originated from the difference between hemoximeters, which could be eliminated using appropriate quality controls.


Asunto(s)
Hemoglobinas/análisis , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Control de Calidad , Detección de Abuso de Sustancias/normas , Adulto , Territorio de la Capital Australiana , Doping en los Deportes , Femenino , Humanos , Laboratorios/normas , Masculino , Detección de Abuso de Sustancias/métodos , Adulto Joven
9.
Drug Test Anal ; 2(11-12): 647-50, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21204297

RESUMEN

Several peptide drugs are being manufactured illicitly, and in some cases they are being made available to the public before entering or completing clinical trials. At the request of Norwegian police and customs authorities, unknown pharmaceutical preparations suspected to contain peptide drugs are regularly subjected to analysis. In 2009, an unknown pharmaceutical preparation was submitted for analysis by liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS). The preparation was found to contain a 29 amino acid peptide with a C-terminal amide function. Based on the interpretation of mass spectrometric data, an amino acid sequence was proposed. The sequence is consistent with a peptide currently marketed under the name CJC-1295. CJC-1295 is a releasing factor for growth hormone and is therefore considered a Prohibited Substance under Section S2 of the WADA Prohibited List. This substance has potential performance-enhancing effects, it is readily available, and there is reason to believe that it is being used within the bodybuilding community.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Fragmentos de Péptidos/aislamiento & purificación , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Preparaciones Farmacéuticas/química , Cromatografía Liquida , Hormona Liberadora de Hormona del Crecimiento/aislamiento & purificación , Espectrometría de Masas en Tándem
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