Abstract. An experiment was conducted to evaluate the effect of various levels of protein and dietary lipids on white snook (Centropomus viridis) performance. A 4 × 2 factorial design was used with 4 protein levels (40%, 46%, 52%, and 58%) and 2 lipid levels (10% and 13%), with 3 replicates per treatment. Fish with an initial weight of 14.80 ± 0.80 g were fed to apparent satiety 3 times a day for 6 weeks. Juvenile growth showed no significant differences among treatments. Feed efficiency was only affected by the protein level in the diet, and the best feed efficiency ratio was obtained with the 52% protein diets; the protein efficiency ratio was significantly lower with the 58% protein diets. The hepatosomatic index decreased with increasing protein content, and the peritoneal fat index increased with dietary lipid level. The condition factor was not affected by the dietary protein or lipid level. Hematocrit and total plasma protein were significantly higher at 40% protein; blood glucose and triglycerides were affected by both nutrients. It is concluded that juvenile C. viridis can be fed diets containing 40% protein and 10% lipids and a protein/energy ratio of 20.69 mg·kJ-1, under the experimental conditions of this study.

Resumen. Se llevó a cabo un experimento para evaluar el efecto de varios niveles de proteína y lípidos dietéticos en el rendimiento de juveniles de robalo blanco (Centropomus viridis). Se realizó un diseño factorial 4 × 2 con 4 niveles de proteína (40%, 46%, 52% y 58%) y 2 niveles de lípidos (10% y 13%), con 3 replicados por tratamiento. Los peces con un peso inicial de 14.80 ± 0.80 g se alimentaron a saciedad aparente 3 veces al día durante 6 semanas. El crecimiento de los juveniles no presentó diferencias significativas entre los tratamientos. La eficiencia alimenticia solo fue afectada por el nivel de proteína en la dieta, y la mejor tasa de eficiencia alimenticia se obtuvo con las dietas con 52% de proteína; el índice de eficiencia proteica fue significativamente menor con las dietas con 58% de proteína. El índice hepatosomático disminuyó al aumentar el contenido de proteína, y el índice de grasa peritoneal aumentó con el nivel de lípidos en la dieta. El factor de condición no fue afectado por el nivel de proteína o lípidos dietéticos. El hematocrito y la proteína total del plasma fueron significativamente mayores con las dietas con 40% de proteína; la glucosa y los triglicéridos en la sangre fueron afectados por ambos nutrientes. Se concluye que los juveniles de C. viridis pueden ser alimentados con dietas que contengan 40% de proteína y 10% de lípidos y una relación proteína/energía de 20.69 mg·kJ-1, bajo las condiciones experimentales de este estudio.

The transition to and through college can affect the mental health of college students. The situation in medical students is particularly worrisome, considering that they have high rates of psychopathology. These mental health problems can be associated with worse academic and professional outcomes and worse patient care. In this scenario, it is relevant to look at how this problem can be addressed considering variables of both mental health and educational systems in medicine. Therefore, initiatives to promote well-being during the career are proposed. The importance of well-being at an institutional level should be defined. Also, the foundations of learning neurosciences from the point of view of well-being should be incorporated. Considering that well-being goes beyond the absence of discomfort, the role of educational environment both in learning and in mental health should be recognized. Proven effective interventions should be incorporated. It must be considered that not every initiative linked to well-being is necessarily positive and that discomfort to a certain extent can be exploited educatively as well. The well-being of medical students is a complex, dynamic and multidimensional issue. These principles are orientations for different actors of the educational process, to define how they will approach this problem in their contexts.

Abstract Introduction: Any abnormal newborn screening (NBS) test should be subjected to appropriate diagnostic tests and should be followed. Once the newborn has been diagnosed and treated, the family should receive comprehensive genetic services. Aim: To present the experience of studying older siblings of patients with inborn errors of metabolism (IEM) identified by NBS in a single-national follow-up reference center. Methods: A retrospective analysis of medical files of the IEM patients detected by NBS was conducted. All those older siblings who tested positive for the same IEM of the patient detected by newborn screening were included. Results: A total of 26 positive siblings from 18 families with seven different IEM were found (phenylketonuria, argininemia, glucose-6-phosphate dehydrogenase deficiency, 3-methylcrotonyl-CoA carboxylase deficiency, dihydropteridine reductase deficiency, tyrosinemia type 3, and medium chain acyl-CoA dehydrogenase deficiency). The age range of the affected siblings was 2 to 19 years old, with a mean age of 8.5 years. Ten older siblings (38.5%) had clinical consequences for the disease, including severe intellectual disability. Conclusions: It is necessary to study older siblings, and family history and genetic counseling of all NBS-detected families should be recommended, especially in countries where expanded NBS programs are beginning.

Abstract: Objective: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. Materials and methods: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. Conclusion: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Resumen: Objetivo: Los errores innatos del metabolismo (EIM) son condiciones genéticas que pueden asociarse con trastornos del desarrollo intelectual (TDI). El objetivo de este estudio es contribuir a la caracterización metabólica de los pacientes con TDI de etiología desconocida. Material y métodos: Se realizará un tamiz metabólico mediante espectrometría de masas-tándem y fluorometría para descartar EIM; además, se analizará el perfil metabolómico de los pacientes con TDI. Conclusión: La identificación de perfiles metabolómicos asociados con los TDI de etiología desconocida contribuirá al desarrollo de nuevos esquemas diagnósticos y terapéuticos para la prevención y tratamiento de los TDI en México.

Abstract: Objective: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. Materials and methods: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. Conclusion: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Resumen: Objetivo: Los errores innatos del metabolismo (EIM) son condiciones genéticas que pueden asociarse con trastornos del desarrollo intelectual (TDI). El objetivo de este estudio es contribuir a la caracterización metabólica de los pacientes con TDI de etiología desconocida. Material y métodos: Se realizará un tamiz metabólico mediante espectrometría de masas-tándem y fluorometría para descartar EIM; además, se analizará el perfil metabolómico de los pacientes con TDI. Conclusión: La identificación de perfiles metabolómicos asociados con los TDI de etiología desconocida contribuirá al desarrollo de nuevos esquemas diagnósticos y terapéuticos para la prevención y tratamiento de los TDI en México.

Resumen El paisaje se sitúa en el plano de contacto entre los hechos naturales y humanos, además, es un producto ecológico, psicológico y social. Su estudio permite incorporar la visión holística, dialéctica y sistémica, propia de la geografía, y se convierte en una vía para la formulación de instrumentos y políticas ambientales en la gestión y la planificación de cuencas hidrográficas. En esta perspectiva, se presenta la metodología para identificar unidades de paisajes antropogénicos, así como la percepción que los agentes sociales tienen frente a estos, el agua y los ecosistemas en la cuenca hidrográfica del río Dagua, localizada al occidente del departamento del Valle del Cauca, Colombia. Para lo anterior, se emplearon métodos de investigación cualitativos y cuantitativos. Los resultados evidencian las condiciones de los paisajes, el agua y los ecosistemas, lo cual se convierte en un aporte para futuros procesos de planificación en la cuenca.

Abstract Landscape is situated in the plane of contact between the natural and human habitats, in addition, it is an ecological, psychological and social product. Studying them allows to incorporate the holistic, dialectical and systemic vision, which is a characteristic of geography, and becomes a way for the formulation of environmental instruments and policies in the management and planning of watersheds. In this perspective, the methodology to identify units of anthropogenic landscapes is presented, as well as the perception that the social agents have against them, considering water and ecosystems in the watershed of the Dagua river, located to the west of the department of Valle del Cauca, Colombia. For this, qualitative and quantitative research methods were used. The results show the conditions of landscapes, water and ecosystems, which becomes a contribution for future planning processes in the watershed.

Resumo A paisagem se situa em um plano de contato entre os eventos naturais e humanos, também e um produto ecológico, psicológico e social. Seu estudo permite incorporar a visão holística, dialética e sistêmica, própria da geografia e se converte em uma via para a formulação de instrumentos e políticas ambientais na gestão e planificação de bacias hidrográficas. Nesta perspectiva, se apresenta a metodologia para identificar unidades de paisagem antropogênicas, assim como a percepção que os agentes sociais tem frente a estes, a água e os ecossistemas na bacia hidrográfica do rio Dagua, localizada a oeste do Estado de Valle del Cauca, Colômbia. Para o interior, se utilizaram métodos de investigação qualitativos e quantitativos. Os resultados evidenciam as condições das paisagens, água e ecossistemas, o qual se converte em um aporte para os futuros processos de planificação na bacia.

Introduction: infantile nephropathic cystinosis (INC) is an autosomal recessive disorder that causes defects in cystine transport with subsequent accumulation in almost all body tissues, especially kidneys. There are few studies regarding the nutritional status assessment of patients with INC. It has been reported that patients with INC showed increased urinary losses of carnitine, resulting in plasma and muscle carnitine deficiency also increased metabolic requirements of carnitine in this patients have also been proposed, but to date carnitine supplementation is controversial. Objective: the aim of this study was to compare carnitine blood concentrations with nutritional status assessed by three anthropometric parameters: body mass index, mid-upper arm circumference and tricipital skin fold in patients with INC. Material and methods: anthropometric assessment of 10 patients with INC which included measurement of weight, height, mid-upper arm circumference and tricipital skin fold thickness. Free carnitine (C0) was measured by tandem mass spectrometry in fasting blood samples. Results: a total of 10 patients with INC were analyzed, 5 with and 5 without renal graft. According to the body mass index, 3/10 presented malnutrition. Muscular mass was found low in 8/10 patients (3 without renal graft and all the transplanted) the mid-upper arm circumference showed correlation with C0 blood concentrations (r² = 0.353); non transplanted patients had C0 levels significantly lower than the transplanted ones (Chi² = 0.0027). Conclusion: in this study we found that 70% of patients had low C0 blood levels that had a correlation with depleted lean body mass. It is recommendable to evaluate the nutritional status of these patients as part of their routine medical evaluation.

Introducción: la cistinosis nefropática infantil (CNI) es una enfermedad genética debida a un defecto del transporte de la cistina, con la subsecuente acumulación de este aminoácido predominantemente en el riñón. Existen pocos estudios sobre la evaluación del estado nutricional en pacientes con esta patología, pero se sabe que tienen una excreción de carnitina urinaria aumentada, lo que puede dar como resultado una deficiencia plasmática y muscular de este compuesto; sin embargo, la suplementación de carnitina en CNI es controversial. Objetivo: comparar la concentración sanguínea de carnitina libre (C0) con el estado nutricional de una cohorte de pacientes con CNI. Material y métodos: evaluación antropométrica mediante la medición de peso, talla, perímetro braquial (PB) y pliegue cutáneo tricipital (PCT). La C0 se cuantificó mediante espectrometría de masas en tándem en muestras de sangre en ayuno. Resultados: se analizaron 10 pacientes con CNI, 5 con y 5 sin trasplante renal. De acuerdo con el IMC, 3/10 presentaron desnutrición. La reserva de masa magra se encontró baja en 8/10 pacientes (3 no trasplantados y todos los trasplantados). El PB mostró correlación con las concentraciones sanguíneas de C0 (r² = 0,353); Los pacientes no trasplantados tuvieron niveles de C0 significativamente más bajos que los trasplantados (Chi² = 0,0027). Conclusión: en esta población de pacientes con CNI se encontró un 70% de sujetos con C0 baja, que se correlaciona con la masa magra disminuida. Es recomendable hacer una evaluación nutricional de rutina que incluya los tres parámetros antropométricos como parte del seguimiento médico-nutricional integral de estos pacientes.

Introduction: Classic phenylketonuria (PKU) is a genetic encephalopathy characterized by impairment of phenylalanine (Phe) metabolism, leading to elevation of blood Phe to toxic levels. Clinical manifestations include irritability, sleep disorders, apathy, seizures, developmental delay, autistic behavior, aggressiveness; mental retardation is the most severe manifestation of the disease. Objective: To describe the findings of brain nuclear magnetic resonance (NMR) and to measure the apparent diffusion coefficient (ADC) of Mexican PKU patients diagnosed by their clinical manifestations in the National Institute of Pediatrics (INP). Material and methods: Retrospective analysis of brain images obtained by NMR from PKU patients. A Signa Excite magnet of 1.5 Tesla with an 8-channel phased array cerebral antenna was used. ADC was measured on the Advantage Workstation 4.2p. Results: Abnormalities in the white and gray matter were observed in all patients; bilateral changes were present in the frontal, temporal, occipital, subcortical and periventricular white matter. ADC was diminished in the peritrigonal and occipital white matter; as well as in the corpus callosum, basal ganglia and cerebellum. One patient had two arachnoid cysts. Conclusion: All PKU patients exhibited the characteristic NMR abnormalities. The mechanisms responsible for brain damage that occur in PKU patients are poorly understood and require further research.

Antecedentes: la fenilcetonuria clásica es una encefalopatía genética caracterizada por una inhabilidad de los individuos para metabolizar la fenilalanina, por lo que su concentración plasmática se eleva a niveles tóxicos. Clínicamente se manifiesta como irritabilidad, alteración del sueño, indiferencia al medio, crisis convulsivas, retraso del neurodesarrollo, conducta autista, agresividad y discapacidad intelectual. Objetivo: describir los hallazgos y cuantificar el coeficiente de difusión aparente en los estudios de imagen de resonancia magnética de cráneo, de pacientes con fenilcetonuria clásica diagnosticada tardíamente en el Instituto Nacional de Pediatría (México). Materiales y métodos: análisis retrospectivo de imágenes cerebrales obtenidas por resonancia magnética en pacientes con fenilcetonuria clásica. Se utilizó un magneto Signa Excite de 1.5 teslas con antena cerebral de ocho canales de arreglo en fase. Se midió el coeficiente de difusión aparente en la estación de trabajo Advantage Workstation 4.2p. Resultados: en los pacientes se observaron alteraciones en las sustancias blanca, gris, o ambas. En la sustancia blanca las lesiones hiperintensas en el área peritrigonal fueron las más frecuentes; se encontraron alteraciones bilaterales en la sustancia blanca frontal, temporal, occipital, subcortical y periventricular. Se observó disminución del coeficiente de difusión aparente en la sustancia blanca peritrigonal, occipital, cuerpo calloso, ganglios basales y cerebelo. Un paciente tenía dos quistes aracnoideos. Conclusión: todos los pacientes estudiados tuvieron las anormalidades características de la enfermedad en las imágenes de resonancia magnética. Los mecanismos causantes de las lesiones cerebrales en la fenilcetonuria, su distribución espacial y su evolución son poco conocidos y requieren de investigaciones posteriores.

Recent findings show that eliminating the gelatinous egg capsule surrounding the fertilized eggs of the puffer fish Sphoeroides annulatus improves embryonic development and hatching rate. In this work, the following 3 different desticking procedures were used to evaluate larval growth and survival: 5 ml L-1 proteolytic protease enzyme (EPP), 1% of pineapple juice (JP) and eggs with no sticky coating on the surface as a control (C). All treatments were carried out in triplicate and the experiment lasted for 33 days. The fertilization percentage obtained was 98.6 ± 1.8% in all treatments. The highest hatching percentage was achieved with EPP (93.03 ± 3.01%) and the lowest with JP (80.97 ± 3.97%). Both total length (LT) (14.4 ± 0.40 mm) and weight (P) (0.118 ± 0.004 g) were significantly higher in the JP treatment. The highest survival rate was obtained with EPP (19.34 ± 1.98%) and differences were found to be statistically significant. The desticking of eggs treated with JP gave a low hatching percentage due to the fruits pH reading of 4 and since fewer organisms were produced, higher growth rate was obtained. Thus, we conclude that removing the adhesive layer of the egg does not affect larval growth and survival.

The effects of different water temperatures (22, 25, 28 and 31ºC) and salinities between 0 and 60 psu (with intervals of 5 psu) on egg incubation of the bullseye puffer (Sphoeroides annulatus) were evaluated in this study. The embryos could not develop at 22ºC and the highest hatching rate for normal larvae was observed at 28ºC. At 0, 50, 55 and 60 psu larvae were unable to develop. Highest hatching rates were obtained at 25, 30 and 35 psu. It was concluded that water temperature and salinity affects the incubation period, embryo development stage and larval survival of the bullseye puffer.

The spotted rose snapper (Lutjanus guttatus) is one of the most commercially important fish species in México. As it is considered a suitable candidate for culture, then it is necessary to identify its nutritional requirements in order to succeed. The aim of this study was to evaluate the effects of different protein and lipid levels on growth and survival of juvenile spotted rose snappers. Nine semi-purified diets were formulated with three protein levels (40, 45 and 50%) and three lipid levels (9, 12 and 15%). Hatchery-produced juvenile spotted rose snappers (2.2 ± 0.1 g) were used throughout the eight-week feeding experiment. Body weight, specific growth rate, condition factor, feed consumption, feed conversion rate, and survival were determined in each treatment at the end of the experiment. The highest weight gained and better feed conversion ratio were obtained in fish fed diets with 45 and 50% protein and their three lipids levels. Survival, feed consumption and condition factor were not affected by the treatments. These results indicate that juvenile spotted rose snappers require a minimum of 45% protein and 9% lipid for maximum growth and survival.

El pargo lunarejo Lutjanus guttatus es una especie con un alto valor comercial en el mercado mexicano y con potencial para su cultivo. Por esto, es necesario determinar sus requerimientos nutricionales para desarrollar dietas específicas y adecuadas para el desarrollo de esta especie, actualmente inexistentes en el mercado mexicano. En el presente estudio, se evaluó el efecto de diferentes niveles de proteína y lípidos totales en la dieta sobre el crecimiento y supervivencia de juveniles de pargo lunarejos producidos en laboratorio. Se formularon nueve dietas semipuras con tres niveles de proteína (40, 45 y 50%) y tres niveles de lípidos (9, 12 y 15%), con las cuales se alimentaron durante 8 semanas a los juveniles de pargo luranejo (peso promedio = 2,2 ± 0,1 g) producidos en criadero. Una vez finalizado el experimento, se determinó el incremento en peso, tasa específica de crecimiento, factor de condición, consumo de alimento, tasa de conversión alimenticia y porcentaje de supervivencia de los organismos. Los peces alimentados con las dietas de 45 y 50% de proteína y sus tres niveles de lípidos obtuvieron mayor incremento en peso corporal y mejores tasa de conversión alimenticia que los organismos alimentados con las dietas de 40% de proteína y sus tres niveles de lípidos. La supervivencia, consumo de alimento y factor de condición no fueron afectados por los diferentes tratamientos. Estos resultados indican que los juveniles de pargo lunarejo requieren por lo menos 45% de proteína y 9% de lípidos totales en la dieta, para su mayor crecimiento y supervivencia.