Abstract The domestication of plants and animals allows the study of different evolutionary processes, including selection, adaptation and speciation. Here we describe recent advances in the study of pumpkins and squashes, which constitute the genus Cucurbita (Cucurbitaceae), being a group of herbaceous plants from the Americas that include between 12 and 15 species. Cucurbita has had six domestication events, four of them occurred in Mexico. This is a relatively recent genus that originated in North America 16 million years ago and its cultivated species maintain high levels of genetic variation. Cucurbita pepo is the species with the highest genetic diversity, diversity associated to two independent domestications, one in Northern Mexico and the other in Southern United States. In another species, Cucurbita argyrosperma, the populations from Yucatan Peninsula represents a genetic pool differentiated from the rest of the species. The study of the genome of C. argyrosperma and related taxa has revealed the regions of its genome associated with domestication. The populations of the species of this genus represent a source of important genetic resources in the face of climate change and constitute a good system for the study of domestication and of different evolutionary processes.

Resumen La domesticación de plantas y animales permite estudiar diferentes procesos evolutivos, como la selección, adaptación y especiación. En este artículo se describen avances recientes en el estudio de las calabazas, las cuales constituyen el género Cucurbita (Cucurbitaceae) siendo un grupo de plantas herbáceas americanas que incluyen entre 12 y 15 especies. Cucurbita ha tenido seis eventos de domesticación, de los cuales cuatro sucedieron en México. Este es un género relativamente reciente, que surgió en Norte América hace 16 millones de años y sus especies cultivadas mantienen una alta variación genética; Cucurbita pepo es la especie que presenta mayor variación genética,variación asociada a dos domesticaciones independientes, una en el norte de México, y otra en el Sureste de los Estados Unidos. En otra especie, Cucurbita argyrosperma, sus poblaciones de la Península de Yucatán, representan una poza genética diferenciada del resto de la especie. El estudio del genoma de C. argyrosperma y taxa cercanos ha revelado las regiones de su genoma asociadas a la domesticación. Las poblaciones de las especies de este género representan una fuente de importantes recursos genéticos frente al cambio climático y constituyen un buen sistema para el estudio de la domesticación y de diferentes procesos evolutivos.

Resumo Fundamento: O treinamento resistido promove benefícios à saúde cardiovascular, a qual é influenciada pela privação de sono. Objetivo: Investigar o efeito prévio do treinamento resistido de alta intensidade sobre a contratilidade miocárdica de ratos privados de sono paradoxal. Métodos: Quarenta ratos machos Wistar foram distribuídos nos grupos controle (CTRL), treinamento resistido (TRES), privação de sono paradoxal por 96 horas (PSP96) e treinamento resistido seguido de privação de sono paradoxal por 96 horas (TRES/PSP96). O treinamento resistido foi de alta intensidade, por 8 semanas, 5x/semana. Vinte e quatro horas após a última sessão de treinamento, os grupos PSP96 e TRES/PSP96 foram submetidos ao protocolo de privação de sono paradoxal e em seguida foi realizado o estudo in vitro da mecânica contrátil do músculo papilar isolado. Resultados: Em comparação ao CTRL, os grupos PSP96 e TRES/PSP96 apresentaram menor comprimento do músculo papilar e aumento da área de secção transversa. Associado a essas alterações, verificou-se a diminuição das derivadas temporais da força na contração e relaxamento em todas as condições avaliadas. Somente o grupo PSP96 apresentou redução da tensão de repouso e lentidão no tempo de relaxamento, sendo este último atenuado pelo treinamento resistido prévio. Conclusão: O treinamento resistido prévio à PSP foi parcialmente protetor contra as alterações contráteis do músculo papilar, minimizando a lentidão no tempo de relaxamento. Assim, o caráter de alta intensidade do protocolo adotado parece não proteger plenamente o tecido cardíaco frente a PSP.

Abstract Background: Resistance training promotes cardiovascular health benefits that may affected by sleep deprivation. Objective: To evaluate the effect of high-intensity resistance training on myocardial contractility in rats subsequently subjected to paradoxical sleep deprivation. Methods: Forty male Wistar rats were distributed into control group (CTRL), resistance training (REST), 96-hour paradoxical sleep deprivation (PSD96) and resistance training followed by 96-hour paradoxical sleep deprivation (REST/PSD96). The animals underwent high-intensity resistance training for 8 weeks, 5x/week. Twenty-four hours after the last training session, the PSD96 and REST/PSD96 groups were submitted to paradoxical sleep deprivation, which was followed by the in vitro study of isolated papillary muscle contractile mechanics. Results: In comparison with the CTRL group, a lower papillary muscle length and increased cross sectional area were found in PSD96 and RETS/PSD96, which were associated with decreased temporal parameters of contraction force and relaxation. Decreased resting tension and slowing of relaxation time were found in the PSD96 group only. This effect was attenuated by previous resistance training. Conclusion: Resistance training partially prevented contractile changes induced by PSD, minimizing the slowing in relaxation time. Thus, high-intensity exercise seems to not fully protect the cardiac tissue from PSD-induced effects.

Introducción: los beneficios de la CPAP dependen del número de horas que el paciente la use. El objetivo del estudio fue establecer, en pacientes con apnea del sueño (SAHS), si hay adecuada adherencia a la CPAP y determinar qué factores referidos por el paciente se relacionan a la no adherencia. Métodos: estudio observacional analítico transversal en pacientes tratados con CPAP. Se definió buena adherencia como uso mínimo de cuatro horas al menos el 70% de los días (registro del dispositivo). Análisis de regresión logística para evaluar los factores relacionados a la no adherencia: presión, resequedad de la vía aérea, problemas con la máscara y falta de educación en el uso de CPAP. Resultados: de 160 pacientes, 88 (55%) tuvieron mala adherencia. La edad, peso, talla, cuello e índice de apneas fueron similares en los grupos con buena y mala adherencia. El Epworth y la presión de CPAP fueron significativamente mayores en el grupo de mala adherencia (p<0.05). El promedio de horas de uso de CPAP en el grupo con buena adherencia fue de 5.1 ± 1.7 horas y en el grupo con mala adherencia fue de 1.9 ± 1.5 horas. Los pacientes sobreestimaron el uso de la CPAP en 2.0 horas: reportadas por el paciente 5.3 horas frente a 3.3 horas según la tarjeta del equipo (p<0.001). El único factor referido por el paciente que se relacionó con la mala adherencia fue la presión de CPAP (OR ajustado: 3,34 [1,34 a 8,30]). Conclusiones: la adherencia al tratamiento con CPAP en pacientes con SAHS es subóptima (mala adherencia en 55% de los pacientes). La principal causa relacionada con la no adherencia según los pacientes fue la intolerancia a la presión del dispositivo. Los pacientes sobreestiman las horas reales de uso del CPAP.

Introduction: the benefits of CPAP depend on the number of hours being used by the patient. The aim of the study was to establish, in patients with sleep apnea (SAHS), if there is adequate adherence to CPAP and to determine what factors reported by the patient are related to non-adherence. Methods: an analytical observational cross-sectional study in patients treated with CPAP. Good adherence was defined as a minimum of 4 hours use at least 70% of days (device score). Logistic regression analysis to assess factors related to non-adherence: pressure, airway dryness, mask problems and lack of education in the use of CPAP. Results: of 160 patients, 88 (55%) had poor adherence. Age, weight, height, neck and apnea index were similar in the groups with good and poor adherence. The Epworth and CPAP pressure were significantly higher in the group of poor adherence (p <.05). The average hours of use of CPAP in the group with good adherence was 5.1 ± 1.7 hours and the poor adherence group was 1.9 ± 1.5 hours. The patients overestimated the use of CPAP in 2.0 hours: 5.3 hours reported by the patient versus 3.3 hours according to the device card (p <0.001). The only factor reported by the patient that was associated with poor adherence was CPAP pressure (adjusted OR: 3.34 [1.34 to 8.30]). Conclusions: adherence to CPAP in patients with SAHS is suboptimal (poor adherence in 55% of patients). The main cause related to non-adherence according to patients was intolerance to the pressure device. Patients overestimate the real hours of CPAP use.

OBJECTIVE: To review Jamaican physicians' adolescent health screening practices by determining their frequency in areas of biomedical, psychological, social, and educational health; the factors that influence these practices; and physicians' perceived level of self-efficacy and their awareness of screening tools and guidelines. METHODS: A questionnaire was mailed to general practitioners, family medicine specialists, and pediatricians in Jamaica. The primary outcome variable was the frequency of physician screening for a range of biomedical, psychosocial, and educational developmental issues in the majority (> 50%) of adolescent patients. Bivariate analyses were performed to determine differences between professional groups. RESULTS: The response rate was 32.3% (n = 213), with 209 responders being suitable for further analysis. The sample comprised 48.8% general practitioners, 33.0% family medicine specialists, and 18.2% pediatricians. Physicians more often screened for biomedical risks than for psychosocial risks, with very low frequencies of screening for psychosocial issues such as mood, suicidal ideation, sexual orientation, and safety concerns. Physicians reported high levels of confidence in discussing most psychosocial issues with adolescent patients. Time limitation and an insufficient knowledge base were the main factors identified as influencing screening practices. CONCLUSIONS: The data suggest unsatisfactory frequency of adolescent health screening by Jamaican physicians, in particular for psychosocial factors. The primary factors identified by physicians as influencing their screening practices have potential for improvement through continued medical education.

OBJETIVO: Analizar las prácticas de examen sistemático de la salud de los adolescentes por parte de los médicos de Jamaica mediante la determinación de la frecuencia con la que llevan a cabo reconocimientos sistemáticos de salud en las áreas biomédica, psicológica, social y educativa; los factores que afectan dichas prácticas sistemáticas; el nivel de autoeficacia percibida por los médicos respecto a ellas y su conocimiento de los instrumentos y las recomendaciones con respecto a los exámenes sistemáticos. MÉTODOS: Se envió por correo un cuestionario a médicos generales, especialistas en medicina familiar y pediatras de Jamaica. La principal variable de evaluación fue la frecuencia con la que los médicos llevan a cabo exámenes sistemáticos sobre varios aspectos biomédicos, psicosociales y del desarrollo educativo en la mayoría (> 50%) de los pacientes adolescentes. Se realizaron análisis bifactoriales a fin de establecer las diferencias entre los grupos de profesionales. RESULTADOS: La tasa de respuesta fue de 32,3% (n = 213) y se consideró que 209 participantes eran adecuados para el análisis posterior. En la muestra, 48,8% eran médicos generales, 33,0% eran especialistas en medicina familiar y 18,2% eran pediatras. Los médicos llevaban a cabo exámenes sistemáticos con más frecuencia para evaluar los riesgos biomédicos que los riesgos psicosociales, y los exámenes sobre aspectos psicosociales como el estado de ánimo, la presencia de ideas suicidas, la orientación sexual y temas relacionados con la seguridad se exploraron muy poco. Los médicos informaron altos niveles de confianza para tratar la mayoría de los temas psicosociales con los pacientes adolescentes. Los principales factores que afectaran las prácticas de examen sistemático fueron la falta de tiempo y la carencia de conocimientos suficientes. CONCLUSIONES: Los datos indican que la frecuencia con la que los médicos de Jamaica llevan a cabo prácticas de examen sistemático relacionadas con la salud de los adolescentes es insuficiente, en particular en lo que respecta a los factores psicosociales. Los principales factores que, según los médicos, afectan sus prácticas con respecto a este tema pueden mejorarse mediante programas de formación médica continua.

A avaliação da toxicidade de uma substância é realizada com o objetivo de predizer os efeitos nocivos que a mesma poderá desencadear quando da exposição humana pelas diversas vias. Para cumprir este propósito, o modelo animal é o mais utilizado nos estudos toxicológicos e requerido nos processos investigativos. Entretanto, a utilização de animais na pesquisa tem sido razão de diversas discussões em função do grande número necessário e do sofrimento causado, principalmente em relação aos estudos de toxicidade aguda. Existe uma tendência mundial para reavaliar a utilização de animais nos experimentos, concretizada a partir de um programa denominado de 3Rs (Reduction, Refinement, Replacement), que objetiva além de diminuir o número de animais, minimizar a dor e o desconforto e buscar alternativas para a substituição dos testes in vivo. Diversas metodologias alternativas já foram implantadas, sendo este um processo complexo que abrange desde o seu desenvolvimento até sua aceitação regulatória e adoção por diversas organizações. Sendo assim, o presente trabalho apresenta abordagem atualizada do Programa 3Rs, com ênfase na sua evolução histórica e nos processos de implantação e validação de métodos alternativos, principalmente aplicados no contexto da avaliação da toxicidade, enfatizando sua importância e utilidade frente à tendência global de harmonização.

Toxicity assessment is the process of predicting the adverse effects that may be caused to an organism by exposuring it to a given chemical and, for regulation purposes, the most used model in toxicity testing is the animal. However, in today's society the use of animals has become a subject of much public health due to the large number of animals used as well as the pain and distress caused, mainly related to acute toxicity testing. The concept of the "Three Rs" - reduction, refinement, and replacement of animal use - emerged as a mean of removing inhumanity from animal experimentation and aiming to lower the number of animals used, in order to decrease the incidence or severity of inhumane procedures and to find alternative procedures to replace in vivo testing. Many alternative toxicological tests have already been implemented, even knowing that this process is very complex and need to be extensively validated and accepted by regulatory bodies. This paper presents an overview on several aspects of the "Three Rs", including historical evolution and implementation and validation of alternative methods, emphasizing its application on toxicity testing and in global harmonization.