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1.
Eur J Sport Sci ; 23(5): 766-773, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35392766

RESUMEN

PURPOSE: To study the effect of inhaling a beta-agonist (salbutamol) compared to placebo on skiing and cycling performance in well-trained elite athletes. METHODS: Three different exercise protocols were used, all with a cross-over double blind placebo-controlled design. Participants inhaled 800 µg salbutamol or a placebo prior to the test, which was repeated on a following day with the participants inhaling the other substance. Fifteen junior elite skiers performed four free-style high intensity sprints (1100 m/work time 3.5-4.5 min). Twelve elite cyclists carried out a short cycling protocol, starting with two 5 min submaximal workloads followed by a maximal intermittent performance test to exhaustion. Another 12 elite cyclists performed the maximal intermittent performance test to exhaustion after a 150 min long submaximal cycling protocol. RESULTS: Group mean time for the ski sprints increased, with no difference between treatment groups. In the short cycling protocol time to exhaustion was 9.1% (95% CI 52-161) lower after inhaling salbutamol compared to placebo and in the long cycling protocol time to exhaustion was 9.1% (95% CI - 121-267) lower after inhaling salbutamol compared to placebo. Blood lactate, heart rate and ventilation increased during submaximal exercise with salbutamol compared to placebo in the short cycling protocol (p < .05). CONCLUSION: This study could not confirm any positive performance effects from inhaling 800 µg salbutamol compared to placebo in skiing and high-intensity intermittent cycling performance. Instead, time to exhaustion in the maximal intermittent performance test was lower in both cycling protocols.HighlightsThere was no difference in performance time between salbutamol and placebo treatment in real-life applicable repeated ski sprints.Time to exhaustion in the maximal intermittent performance test was 9.1% lower after inhaling salbutamol compared to placebo, both when performed after 10 and 150 min of submaximal cycling.


Asunto(s)
Albuterol , Ejercicio Físico , Humanos , Albuterol/farmacología , Ejercicio Físico/fisiología , Ciclismo/fisiología , Respiración , Prueba de Esfuerzo , Método Doble Ciego , Resistencia Física/fisiología , Estudios Cruzados , Consumo de Oxígeno
2.
Environ Int ; 119: 544-557, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30077002

RESUMEN

Brominated flame-retardants (BFRs) such as polybrominated diphenyl ethers (PBDE) and hexabromocyclododecane (HBCD) are considered hazardous to human health. Due to their persistence, they are still present in the environment and in biota and seafood is major contributor of BFRs to human exposure. Here, we used data from >9700 samples of wild and farmed fish, fish feed and fish feed ingredients collected from the North Atlantic between 2006 and 2016 aiming to investigate factors influencing the risk assessments of BFRs. Due to most representative number of analyses, PBDEs were the main focus of investigation. Mean ∑PBDE in fillet samples ranged from below quantification in Atlantic cod fillet to 2.0 µg kg-1 in Atlantic halibut. The main congener contributing to the ∑PBDE in all species was BDE 47. Factors affecting the level of BFR in seafood were multifaceted, and the levels were within species mainly determined by fish age, geographical origin and time of sampling. BDE 47, 99, 153 and HBCD were selected for margin of exposure (MOE) evaluation. When other sources of BFR than seafood were excluded, our risk assessment showed low risk at the current dietary intake of seafood. However, the dietary intake of BDE 99 may be of concern for toddlers when all sources are considered. The choice of fish species, dietary studies, choice of statistics, as well as exposure from other sources than seafood, were all factors that influenced the final MOE of BFRs. We propose the use of regression on order statistics as a tool for risk assessment, to illustrate means and spreads in large surveillance datasets to avoid the issue of measurements below the limit of quantification. A harmonized, updated evaluation of the risk associated with exposure to BFRs from diet, air and dust is warranted, where the fish species most commonly consumed also is taken into consideration.


Asunto(s)
Exposición Dietética/análisis , Retardadores de Llama/análisis , Contaminación de Alimentos/análisis , Éteres Difenilos Halogenados/análisis , Hidrocarburos Bromados/análisis , Alimentos Marinos/análisis , Adolescente , Adulto , Alimentación Animal/análisis , Animales , Océano Atlántico , Preescolar , Dieta , Monitoreo del Ambiente , Explotaciones Pesqueras , Peces , Humanos , Lactante , Medición de Riesgo
3.
J Agric Food Chem ; 53(19): 7544-51, 2005 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16159184

RESUMEN

Application of aroma extract dilution analysis on the volatiles isolated from a Bavarian Pilsner-type beer revealed 40 odor-active constituents in the flavor dilution (FD) factor range of 16-2048, among which ethyl octanoate, (E)-beta-damascenone, 2- and 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD factor of 2048. After quantitation of the 26 odorants showing FD factors > or =128 by stable isotope dilution analysis and determination of their odor thresholds in water, odor acitivity values (OAVs) were calculated. The results indicated ethanol, (E)-beta-damascenone, (R)-linalool, acetaldehyde, and ethyl butanoate with the highest OAVs, followed by ethyl 2-methylpropanoate and ethyl 4-methylpentanoate, which was previously unknown in beer. Finally, the overall aroma of the beer could be mimicked for the first time by recombining 22 reference odorants in the same concentrations as they occurred in the beer using ethanol/water as the matrix.


Asunto(s)
Cerveza/análisis , Odorantes/análisis , Acetaldehído/análisis , Monoterpenos Acíclicos , Ácido Butírico/análisis , Etanol/análisis , Alemania , Monoterpenos/análisis , Norisoprenoides/análisis
4.
Environ Int ; 74: 274-80, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25454244

RESUMEN

BACKGROUND: Environmental pollutants such as dioxins and PCBs, heavy metals, and organochlorine pesticides are a global threat to food safety. In particular, the aquatic biota can bioaccumulate many of these contaminants potentially making seafood of concern for chronic exposure to humans. OBJECTIVES: The main objective was to evaluate trends of contaminant levels in Norwegian farmed Atlantic salmon in light of the derived tolerable intakes. METHODS: Through an EU-instigated surveillance programme, the Norwegian Food Safety Authority (NFSA) has between 1999 and 2011 collected more than 2300 samples of Norwegian farmed Atlantic salmon (Salmo salar) for contaminant analyses. The fillets of these fish were homogenised and analysed for dioxins, PCBs, heavy metals and organochlorine pesticides. RESULTS: The levels of the contaminants mercury, arsenic, dioxins, dioxin-like PCBs and DDT in Norwegian farmed salmon fillet have decreased during our period of analyses. The levels of cadmium, lead and several organochlorine pesticides were too close to the limit of quantification to calculate time trends. For PCB6 and quantifiable amounts of pesticides, except DDT, stable levels were observed. CONCLUSION: The contaminant levels in Norwegian farmed salmon have generally decreased between 1999 and 2011. Excluding other dietary sources, the levels of dioxins and dioxin-like PCBs in 2011 allowed consumption of up to 1.3kg salmon per week to reach the tolerable weekly intake. The group of contaminants which was the limiting factor for safe consumption of Norwegian farmed salmon, based on currently established TWI values, is the sum of dioxins and dioxin-like PCBs.


Asunto(s)
Contaminantes Ambientales/análisis , Salmo salar , Animales , Acuicultura , Dioxinas/análisis , Inocuidad de los Alimentos , Hidrocarburos Clorados/análisis , Metales Pesados/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Alimentos Marinos
5.
J Agric Food Chem ; 51(24): 7100-5, 2003 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-14611178

RESUMEN

A stable isotope dilution assay (SIDA) was developed for the quantitation of both linalool enantiomers using synthesized [2H(2)]R/S-linalool as the internal standard. For enrichment of the target compound from beer, a solid phase microextraction method (SPME) was developed. In comparison to the more time-consuming extraction/distillation cleanup of the beer samples, the results obtained by SPME/SIDA were very similar, even under nonequilibration conditions. Analysis of five different types of beer showed significant differences in the linalool concentrations, which were clearly correlated with the intensity of the hoppy aroma note as evaluated by a sensory panel. In addition, significant differences in the R/S ratios were measured in the beers. The SPME/SIDA yielded exact data independently from headspace sampling parameters, such as exposure time or ionic strength of the solution.


Asunto(s)
Cerveza/análisis , Monoterpenos/análisis , Monoterpenos Acíclicos , Deuterio , Cromatografía de Gases y Espectrometría de Masas , Técnicas de Dilución del Indicador , Marcaje Isotópico , Solventes , Estereoisomerismo , Volatilización
6.
Cleve Clin J Med ; 67(11): 818, 821-4, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11104332

RESUMEN

Nicotine replacement and bupropion have shown significant benefits for those seeking pharmacologic assistance with smoking cessation. This discussion reviews the efficacy literature for both treatments, including potential side effects.


Asunto(s)
Cese del Hábito de Fumar/métodos , Bupropión/uso terapéutico , Humanos , Nicotina/uso terapéutico
7.
Anal Chim Acta ; 573-574: 181-8, 2006 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-17723522

RESUMEN

An efficient and selective analytical method for determination and quantification of 24 various polyaromatic hydrocarbons (PAHs) in blue mussel (Mytilus edulis), salmon fillet (Salmo salar), fish oil and fish feed has been developed. The samples were extracted by means of accelerated solvent extraction (ASE) technique followed by a purification step with gel permeation chromatography (GPC). Identification and quantification were performed by using GC/MS. The novel combination of silica and alumina in the extraction step furnishes highly purified analytes for the most of the 24 PAHs investigated, and thus a fast and selective analytical method is developed. A small limitation with the method concerns the quantification of acenaphthene (Ace), fluorene (Fl), pyrene (Py) and benzo[a]anthracene (BaA), as the found values for these compounds do not match the certified values (SRM 2977, mussel tissue). Chrysene (Chr) and triphenylene (Tph) give unresolved peaks. The limits of detection (LOD) and limits of quantification (LOQ) found for benzo[a]pyrene (BaP) were 1.7 and 0.44 pg/g (LOD), and 5.8 and 1.5 pg/g (LOQ) for salmon fillet and blue mussel, respectively. This is in a very good accordance with respect to the European Community legislation for official control of BaP levels in foodstuff. The method may be used for qualitative identification of petroleum compounds in marine matrixes.

8.
HNO ; 53(7): 655-60, 2005 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-15565423

RESUMEN

BACKGROUND: 1-2/1,000 newborns are affected by connatal permanent hearing impairment. Clinical diagnosis is often delayed. This demands newborn hearing screening (NHS). Some questions regarding the optimal method remain unsolved. METHODS: The newborns in the obstetrical department (low-risk group) are tested by automated transitory evoked otoacustic emissions (TEOAE). TEOAE-fail is followed by automated auditory brainstem response (AABR) examination. All sick newborns admitted to the pediatric department (high-risk group) are primarily tested using AABR. Pathological AABR-testing leads to pedaudiological diagnostic work-up. RESULTS: In the low-risk group, 82 out of 1,584 newborns failed TEOAE-testing (recall 5.18%). Only 5 of these patients failed consecutive AABR examination (recall 0.32%). Permanent hearing loss was finally confirmed in 3 children (0.13%). 10 out of 755 newborns in the high-risk group failed AABR-testing (1.32%). In 6 of these children, hearing loss was confirmed (0.79%). CONCLUSION: A two-tier screening process as described is able to reduce recall rate, overall expenses and parental anxiety.


Asunto(s)
Audiometría de Respuesta Evocada , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Pruebas Auditivas/estadística & datos numéricos , Tamizaje Neonatal/organización & administración , Emisiones Otoacústicas Espontáneas/fisiología , Diagnóstico Precoz , Femenino , Humanos , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Masculino , Grupo de Atención al Paciente , Reproducibilidad de los Resultados , Medición de Riesgo , Procesamiento de Señales Asistido por Computador
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