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1.
BMC Med Educ ; 24(1): 460, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671400

RESUMEN

BACKGROUND: Despite the recognized advantages of Peer-Assisted Learning (PAL) in academic settings, there is a notable absence of research analyzing its effects on students' Academic Burnout. This study aims to cover this gap by assessing the underlying effectiveness of Informal Peer-Assisted Learning (IPAL) as a cooperative learning method, focusing on its potential to mitigate academic burnout among medical students. METHODS: In 2022, a cross-sectional study was conducted at the School of Medicine, Universidad Central del Caribe, in Puerto Rico. The research team gathered data from 151 participants, 49.19% of 307 total student body. This cohort included 76 female students, 71 male students, and 4 individuals saying other. The School Burnout Inventory questionnaire (SBI-9) was employed to assess Academic Burnout, along with an added query about self-reported IPAL. The SBI-9 underwent validation processes to ascertain its reliability and validity, incorporating the Exploratory Factor Analysis and Confirmatory Factor Analysis. Following this, the investigators conducted an analysis to determine the correlation between academic burnout levels and involvement in IPAL. RESULTS: The validation process of the questionnaire affirmed its alignment with an eight-item inventory, encapsulating two principal factors that elucidate academic burnout. The first factor pertains to exhaustion, while the second encompasses the combined subscales of cynicism and inadequacy. The questionnaire shows high reliability (Cronbach's alpha = 0.829) and good fit indices (Comparative Fit Index = 0.934; Tucker-Lewis Index = 0.902; Standardized Root Mean Squared Residual = 0.0495; Root Mean Squared Error of Approximation = 0.09791; p-value < 0.001). The factors proven in the selected model were used to evaluate the correlation between Academic Burnout and IPAL. Students engaged in IPAL showed significantly lower academic burnout prevalence compared to those who never participated in such practices, with a mean academic burnout score of 44.75% (SD 18.50) for IPAL engaged students versus 54.89% (SD 23.71) for those who never engaged in such practices (p-value < 0.013). Furthermore, within the group engaged in IPAL, students displayed lower levels of cynicism/inadequacy 41.98% (SD 23.41) compared to exhaustion 52.25% (SD 22.42) with a p-value < 0.001. CONCLUSIONS: The results of this study underscore a notable issue of academic burnout among medical students within the surveyed cohort. The investigation reveals a significant correlation between Academic Burnout and IPAL, suggesting that incorporating IPAL strategies may be beneficial in addressing burnout in medical education settings. However, further research is needed to explore potential causal mechanisms.


Asunto(s)
Grupo Paritario , Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , Femenino , Masculino , Estudios Transversales , Agotamiento Profesional , Encuestas y Cuestionarios , Puerto Rico , Adulto Joven , Adulto , Reproducibilidad de los Resultados , Educación de Pregrado en Medicina
2.
Neuropharmacology ; 88: 110-21, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25261018

RESUMEN

The ventral tegmental area (VTA) plays an important role in reward and motivational processes involved in drug addiction. Previous studies have shown that alpha1-adrenoreceptors (α1-AR) are primarily found pre-synaptically at this area. We hypothesized that GABA released onto VTA-dopamine (DA) cells is modulated by pre-synaptic α1-AR. Recordings were obtained from putative VTA-DA cells of male Sprague-Dawley rats (28-50 days postnatal) using whole-cell voltage clamp technique. Phenylephrine (10 µM; α1-AR agonist) decreased the amplitude of GABAA receptor-mediated inhibitory postsynaptic currents (IPSCs) evoked by electrical stimulation of afferent fibers (n = 7; p < 0.05). Prazosin (1 µM, α1-AR antagonist), blocked this effect. Paired-pulse ratios were increased by phenylephrine application (n = 13; p < 0.05) indicating a presynaptic site of action. Spontaneous IPSCs frequency but not amplitude, were decreased in the presence of phenylephrine (n = 7; p < 0.05). However, frequency or amplitude of miniature IPSCs were not changed (n = 9; p > 0.05). Phenylephrine in low Ca(2+) (1 mM) medium decreased IPSC amplitude (n = 7; p < 0.05). Chelerythrine (a protein kinase C inhibitor) blocked the α1-AR action on IPSC amplitude (n = 6; p < 0.05). Phenylephrine failed to decrease IPSCs amplitude in the presence of paxilline, a BK channel blocker (n = 7; p < 0.05). Taken together, these results demonstrate that α1-ARs at presynaptic terminals can modulate GABA release onto VTA-DA cells. Drug-induced changes in α1-AR could contribute to the modifications occurring in the VTA during the addiction process.


Asunto(s)
Neuronas Dopaminérgicas/fisiología , Receptores Adrenérgicos alfa 1/metabolismo , Área Tegmental Ventral/fisiología , Ácido gamma-Aminobutírico/metabolismo , Adrenérgicos/farmacología , Animales , Benzofenantridinas/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Estimulación Eléctrica , Indoles/farmacología , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Potenciales Postsinápticos Inhibidores/fisiología , Canales de Potasio de Gran Conductancia Activados por el Calcio/antagonistas & inhibidores , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Masculino , Potenciales Postsinápticos Miniatura/efectos de los fármacos , Potenciales Postsinápticos Miniatura/fisiología , Técnicas de Placa-Clamp , Fenilefrina/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Prazosina/farmacología , Terminales Presinápticos/efectos de los fármacos , Terminales Presinápticos/fisiología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Ratas Sprague-Dawley , Técnicas de Cultivo de Tejidos , Área Tegmental Ventral/efectos de los fármacos
3.
Int J Dev Biol ; 53(1): 101-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19123131

RESUMEN

Thyroid hormones--particularly triiodothyronine, T3--play a critical role in the morphological transformations comprising metamorphosis in larval bullfrogs (Rana catesbeiana). Traditional staging criteria for anuran larvae incompletely distinguish physiological and behavioral changes during growth. We therefore first developed a new parameter to describe larval growth, the developmental index (DI), which is simply the ratio between the tail length of the larva and its head diameter. Using the DI we were able to identify two distinct populations classifying the larvae during growth along a continuous linear scale with a cutoff value of DI at 2.8. Classification based on the DI, used in this study, proved an effective complement to existing classifications based on developmental staging into pre- or pro-metamorphic stages. Exposure to T3 in the water induced a rapid (beginning within 5 min) and significant decrease (approximately 20-40%) in locomotor activity, measured as total distance traversed and velocity. The largest decrease occurred in more developed larvae (DI<2.8). To determine correlated changes in the neuromuscular junctions during metamorphosis and apoptotic tail loss, miniature endplate currents from tail muscle were recorded during acute exposure to a hypertonic solution, which simulates an apoptotic volume decrease. Our results support a role for T3 in regulating larval locomotor activity during development, and suggest an enhanced response to volume depletion at the neuromuscular junction of older larvae (DI<2.8) compared to younger animals (DI> or =2.8). We discuss the significance of the possible role of an apoptotic volume decrease at the level of the neuromuscular junction.


Asunto(s)
Locomoción/efectos de los fármacos , Locomoción/fisiología , Metamorfosis Biológica/efectos de los fármacos , Rana catesbeiana/crecimiento & desarrollo , Natación/fisiología , Triyodotironina/farmacología , Animales , Mejilla/fisiología , Fenómenos Electrofisiológicos
4.
Ethn Dis ; 18(2 Suppl 2): S2-230-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18646355

RESUMEN

INTRODUCTION: Few studies exist on thyroid status and ovarian dysfunction, although the prevalence of thyroid disease, particularly hypothyroidism, increases with advanced age and is more common in women. Loss of ovarian function is a lengthy process, and it is well known that follicle-stimulating hormone (FSH) increases with age and is correlated with loss of ovarian reserves. Limited information is available on FSH and thyroid-stimulating hormone (TSH) status in healthy euthyroid women in pre- and postmenopause states. We propose that patterns in FSH levels depend on the menopause state and that a possible relationship with TSH is present in mature women. METHODS: Baseline data from the study Health and Menopause in Hispanic Women in Puerto Rico were used. Eligible women were 30-84 years old. Demographic data and lifestyle and health information were collected through a questionnaire, and blood chemistries were analyzed. RESULTS: In women without thyroid disease, the median TSH was 1.97 mIU/L, and for euthyroid women the median was 1.84 mIU/L; no difference was observed between pre- and postmenopause states. A positive tendency was found between FSH levels and age in this group. CONCLUSIONS: This report compares the value of TSH in Puerto Rican women during pre- and postmenopausal states, and our findings are different from those in other ethnic groups. FSH levels correlate with age, and the general tendency of FSH to increase with age differs according to menopause state. No correlation between TSH and FSH levels was found in this study.


Asunto(s)
Hormona Folículo Estimulante/sangre , Menopausia/sangre , Tirotropina/sangre , Adulto , Anciano , Anciano de 80 o más Años , Hispánicos o Latinos , Humanos , Persona de Mediana Edad , Puerto Rico/etnología , Análisis de Regresión , Encuestas y Cuestionarios
5.
J Neurosci Res ; 71(5): 670-8, 2003 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12584725

RESUMEN

Thyroid hormones (THs), primarily 3,3',5-triiode-(L)-thyronine (T(3)), have been clearly established as natural inducers of apoptosis during metamorphosis of anuran embryos. We decided to use this phenomenon to test the hypothesis that, prior to genomic activation, T(3) has acute actions in the neuromuscular junction (NMJ) of the tail of amphibian embryos. We detected a dramatic increase in the production of miniature end-plate currents (MEPCs) 2-5 min after continuous application of T(3) (250 nM) using focal recordings under voltage clamp. Furthermore, this increase in the spontaneous release of neurotransmitter, evaluated by the MEPC frequency, was maintained for several hours. Reverse-T(3), the "inhibitory" form of THs, prevented this increase in MEPC frequency, suggesting that this is probably a highly specific action of T(3). In addition, the elevation in MEPC frequency induced by T(3) was unchanged in the presence or absence of extracellular calcium. The T(3)-mediated increase in MEPC frequency was blocked by niflumic acid, a nonsteroidal antinflammatory fenamate used to prevent the apoptotic volume decrease observed in many systems. The present study demonstrated that T(3) induces a remarkable nongenomic action in the NMJ of the tadpole tail at pre- and promatamorphic stages.


Asunto(s)
Metamorfosis Biológica/fisiología , Unión Neuromuscular/efectos de los fármacos , Cola (estructura animal)/inervación , Triyodotironina Inversa/farmacología , Triyodotironina/farmacología , Acetilcolina/metabolismo , Animales , Calcio/metabolismo , Canales de Cloruro/antagonistas & inhibidores , Espacio Extracelular/metabolismo , Técnicas In Vitro , Larva , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Unión Neuromuscular/metabolismo , Unión Neuromuscular/fisiología , Neurotransmisores/metabolismo , Ácido Niflúmico/farmacología , Técnicas de Placa-Clamp , Rana catesbeiana , Cola (estructura animal)/efectos de los fármacos , Cola (estructura animal)/fisiología , Triyodotironina/antagonistas & inhibidores
6.
Acta cient. venez ; 42(3): 160-2, 1991. ilus, tab
Artículo en Inglés | LILACS | ID: lil-113297

RESUMEN

Se adaptó y empleó la corriente sináptica espontánea en la unión neuromusuclar de la cola de renacuajos de Bufo marinus


Asunto(s)
Animales , Bufo marinus , Unión Neuromuscular/ultraestructura , Sinapsis/ultraestructura , Cola (estructura animal)/ultraestructura , Microscopía Electrónica de Rastreo
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