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1.
J Chromatogr A ; 1298: 95-102, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23746372

RESUMEN

A RP-HPLC method with pre-column derivatization was developed and validated for the simultaneous quantification of carnosine (Carn), acetylcarnitine taurinate (AC-Tau), asparagine (Asn), potassium aspartate (Asp) and for the determination of phosphoserine (p-Ser) in new and commercial alimentary supplements. The effect of complex matrices was evaluated by the study of the amino acid derivatization reaction with 2,4-dinitrofluorobenzene (DNFB) both in standard and placebo solutions. The reaction was carried out for 20 min at 70 °C in alkaline medium (pH10) for p-Ser analysis, whereas for 60 min in the case of Carn, AC-Tau, Asn and Asp analysis. The adducts have been separated on a Discovery RP Amide C16 (250 mm×4.6mm, i.d.) column using a mobile phase consisting of acetonitrile (ACN) and triethylammonium (TEA) phosphate buffer (pH 3, 0.05 M) under gradient elution conditions at a flow-rate of 0.8 mL/min. Detection was set at λ=360 nm. The validation parameters such as linearity, sensitivity, accuracy, precision and specificity were found to be highly satisfactory. Linear responses were observed by placebo solutions (determination coefficient ≤0.9996). Intra-day precision (relative standard deviation, RSD) was ≤1.06% for corrected peak area and ≤0.99% for retention times (tR) without significant differences between intra- and inter-day data. Recovery studies showed good results for all examined compounds (from 97.7% to 101.5%) with RSD ranging from 0.5% to 1.3%). The high stability of derivatized compound solutions at room temperature means an undoubted advantage of the method allowing the simultaneous preparation of a large number of samples and consecutive chromatographic analyses by the use of an autosampler. The developed method can be considered suitable for the quality control of new and commercial products.


Asunto(s)
Acetilcarnitina/análisis , Asparagina/análisis , Ácido Aspártico/análisis , Carnosina/análisis , Cromatografía Líquida de Alta Presión/métodos , Fosfoserina/análisis , Reproducibilidad de los Resultados
2.
Neurosci Lett ; 540: 37-42, 2013 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-23206748

RESUMEN

Both motor imagery and action observation have been shown to play a role in learning or re-learning complex motor tasks. According to a well accepted view they share a common neurophysiological basis in the mirror neuron system. Neurons within this system discharge when individuals perform a specific action and when they look at another individual performing the same or a motorically related action. In the present paper, after a short review of literature on the role of action observation and motor imagery in motor learning, we report the results of a kinematics study where we directly compared motor imagery and action observation in learning a novel complex motor task. This involved movement of the right hand and foot in the same angular direction (in-phase movement), while at the same time moving the left hand and foot in an opposite angular direction (anti-phase movement), all at a frequency of 1Hz. Motor learning was assessed through kinematics recording of wrists and ankles. The results showed that action observation is better than motor imagery as a strategy for learning a novel complex motor task, at least in the fast early phase of motor learning. We forward that these results may have important implications in educational activities, sport training and neurorehabilitation.


Asunto(s)
Imaginación , Aprendizaje , Percepción de Movimiento , Movimiento , Adulto , Animales , Aprendizaje por Asociación , Fenómenos Biomecánicos , Encéfalo/fisiología , Femenino , Humanos , Conducta Imitativa , Masculino , Neuronas Espejo/fisiología , Modelos Psicológicos , Práctica Psicológica , Rango del Movimiento Articular , Aprendizaje Seriado , Adulto Joven
3.
J Pharm Biomed Anal ; 48(3): 754-9, 2008 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-18818040

RESUMEN

Furoin, a benzoin analogue, was examined as novel fluorogenic reagent for the selective and sensitive LC determination of various guanidines after pre-column derivatization. The derivatization reaction was carried out at 100 degrees C for 5 min to give adducts that were separated on a Phenomenex Synergi MAX-RP column and detected at lambda(em)=410 nm with lambda(ex)=325 nm. The reagent showed to be useful both for determining together arginine (Arg) and creatine (CT) in dietary supplements under elution isocratic conditions and for the simultaneous analysis of a variety of guanidines in biological samples (human plasma and urine) under elution gradient conditions. The detection limits ranged from 7 to 25 fmol. Recovery studies showed good results for all determined guanidino compounds (85.6-106.2%; R.S.D.=1.1-6.2%).


Asunto(s)
Benzoína/análogos & derivados , Benzoína/química , Cromatografía Liquida/métodos , Guanidinas/análisis , Indicadores y Reactivos/química , Calibración , Suplementos Dietéticos/análisis , Furanos , Guanidinas/sangre , Guanidinas/orina , Humanos , Estructura Molecular , Estándares de Referencia , Sensibilidad y Especificidad , Factores de Tiempo
4.
Amino Acids ; 20(1): 1-11, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11310926

RESUMEN

Branched chain amino acids (BCAA) stimulate protein synthesis, and growth hormone (GH) is a mediator in this process. A pre-exercise BCAA ingestion increases muscle BCAA uptake and use. Therefore after one month of chronic BCAA treatment (0.2 gkg(-1) of body weight), the effects of a pre-exercise oral supplementation of BCAA (9.64 g) on the plasma lactate (La) were examined in triathletes, before and after 60 min of physical exercise (75% of VO2 max). The plasma levels of GH (pGH) and of growth hormone binding protein (pGHBP) were also studied. The end-exercise La of each athlete was higher than basal. Furthermore, after the chronic BCAA treatment, these end-exercise levels were lower than before this treatment (8.6+/-0.8 mmol L(-1) after vs 12.8+/-1.0 mmol L(-1) before treatment; p < 0.05 [mean +/- std. err.]). The end-exercise pGH of each athlete was higher than basal (p < 0.05). Furthermore, after the chronic treatment, this end-exercise pGH was higher (but not significantly, p = 0.08) than before this treatment (12.2+/-2.0 ng mL(-1) before vs 33.8+/-13.6 ngmL(-1) after treatment). The end-exercise pGHBP was higher than basal (p < 0.05); and after the BCAA chronic treatment, this end-exercise pGHBP was 738+/-85 pmol L(-1) before vs 1691+/-555 pmol L(-1) after. pGH/pGHBP ratio was unchanged in each athlete and between the groups, but a tendency to increase was observed at end-exercise. The lower La at the end of an intense muscular exercise may reflect an improvement of BCAA use, due to the BCAA chronic treatment. The chronic BCAA effects on pGH and pGHBP might suggest an improvement of muscle activity through protein synthesis.


Asunto(s)
Aminoácidos de Cadena Ramificada/farmacología , Proteínas Portadoras/sangre , Ejercicio Físico , Hormona de Crecimiento Humana/sangre , Ácido Láctico/sangre , Adulto , Aminoácidos de Cadena Ramificada/farmacocinética , Peso Corporal/efectos de los fármacos , Suplementos Dietéticos , Humanos , Ácido Láctico/metabolismo , Masculino , Persona de Mediana Edad , Carrera , Natación , Factores de Tiempo
5.
Clin Ter ; 143(5): 417-20, 1993 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-8275658

RESUMEN

Therapeutic muds have been applied-at "Terme dei Papi", Viterbo-to 30 subjects with subchronic extra-articular rheumatism (S.I.R., Italy 1986). Favourable effects have been obtained in a great majority of subjects treated. Improvement was obtained concerning provoked pain, spontaneous pain as well as function of sprained joints.


Asunto(s)
Balneología , Peloterapia , Enfermedades Reumáticas/terapia , Medicina Deportiva , Femenino , Calor , Humanos , Italia , Masculino , Manejo del Dolor
6.
Radiol Med ; 84(3): 236-41, 1992 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-1329157

RESUMEN

Cranial CT and/or MRI examinations were performed in 8 patients affected with mucopolysaccharidosis. Two patients were affected with mucopolysaccharidosis IH,1 had mucopolysaccharidosis IS, 1 had mucopolysaccharidosis IV A and 4 presented mucopolysaccharidosis VI. CT and MRI showed white matter changes consisting of symmetric and diffuse hypodense areas on CT, large areas and multiple spots of prolonged T1 and T2 value on MRI. Reduced gray/white matter contrast was demonstrated on T2-weighted sequences. Furthermore, CT and MRI showed thickening of the dura mater at the cranio-cervical junction, which caused subarachnoid space narrowing in all patients. Spinal cord compression was detected in 4 patients. Additional findings were mild to severe hydrocephalus, skull dysplasia and odontoid dysplasia. Owing to the progressive clinical course of all mucopolysaccharidosis, the authors stress the importance of a careful study of the cranio-cervical junction in all the patients with mucopolysaccharidosis examined by CT or MRI in order to demonstrate essential thickening of the dura mater. In the patients with symptomatic cord compression, surgery should be considered.


Asunto(s)
Imagen por Resonancia Magnética , Mucopolisacaridosis/diagnóstico , Cráneo/diagnóstico por imagen , Cráneo/patología , Tomografía Computarizada por Rayos X , Adolescente , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Niño , Preescolar , Medios de Contraste , Femenino , Gadolinio , Gadolinio DTPA , Humanos , Aceite Yodado , Imagen por Resonancia Magnética/métodos , Masculino , Compuestos Organometálicos , Ácido Pentético
7.
Eur J Epidemiol ; 5(3): 279-84, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2792305

RESUMEN

Calves fed with colostrum from cows vaccinated with an inactivated rotavirus vaccine were refractory to experimental infection with strain 81/36F of bovine rotavirus. In the field study, 458 pregnant cows from 26 herds were involved. In each herd, cows were selected and randomly subdivided in two groups. Cows in one group (248 head in total) were vaccinated, whereas cows in the other group (210 head in total) were left as unvaccinated controls. At calving, colostrum was collected from each cow and stored at -30 degrees C until used for feeding calves. The newborn calves, beginning the second day of life and for the next 7-10 days, were each fed a daily supplement of 400 ml of colostrum from its dam. The diarrhea occurred in 86 (40.9%) calves that had received colostrum from unvaccinated dams (normal colostrum), and in 7 (2.8%) calves which were fed colostrum from vaccinated dams (immune colostrum). The disease was very severe in the normal colostrum-fed calves and 52 of them died. By contrast, the 7 immune colostrum-fed calves displayed a rather mild enteric condition, and all recovered without any sequela being observed.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Calostro/inmunología , Infecciones por Rotavirus/veterinaria , Vacunas Virales/administración & dosificación , Animales , Anticuerpos Antivirales/biosíntesis , Bovinos , Enfermedades de los Bovinos/etiología , Enfermedades de los Bovinos/mortalidad , Diarrea/etiología , Diarrea/mortalidad , Diarrea/veterinaria , Femenino , Inmunización/veterinaria , Embarazo , Distribución Aleatoria , Infecciones por Rotavirus/mortalidad , Infecciones por Rotavirus/prevención & control , Vacunas de Productos Inactivados
8.
Microbiologica ; 11(4): 379-85, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2851089

RESUMEN

Pregnant cows were given the first injection of an inactivated bovine rotavirus vaccine approximately 4 weeks before calving and a second injection just before calving. This led to the enhancement of rotavirus antibody titers in their colostrum as well as in the milk for at least 5 days after parturition. Thus, when newborn calves were fed with the mammary secretions obtained from the vaccinated cows daily for 5 consecutive days they were fully refractory to experimental infection with 81/36F bovine rotavirus. By contrast, the calves which were given the mammary secretions from unvaccinated cows, had clinical signs consistent with rotavirus infection and viral shedding. Based on these results it is suggested that vaccination of cows according to the scheme followed in this experiment, i.e., two injections within the last month of pregnancy, might be a valid approach which depending on confirmation under field conditions, could help reduce the incidence of rotavirus-induced diarrhea in newborn calves.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Calostro/inmunología , Diarrea/veterinaria , Inmunidad Materno-Adquirida , Infecciones por Rotavirus/veterinaria , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/análisis , Bovinos , Diarrea/prevención & control , Femenino , Lactosa/inmunología , Embarazo , Rotavirus/inmunología , Infecciones por Rotavirus/prevención & control , Vacunación/veterinaria , Vacunas Virales/inmunología
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