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l-galactono-1,4-lactone dehydrogenase (GALDH) catalyzes the terminal step of vitamin C biosynthesis in plant mitochondria. Here we investigated the communication between Arabidopsis thaliana GALDH and its natural electron acceptor cytochrome c (Cc). Using laser-generated radicals we observed the formation and stabilization of the GALDH semiquinone anionic species (GALDHSQ ). GALDHSQ oxidation by Cc exhibited a nonlinear dependence on Cc concentration consistent with a kinetic mechanism involving protein-partner association to form a transient bimolecular complex prior to the electron transfer step. Oxidation of GALDHSQ by Cc was significantly impaired at high ionic strength, revealing the existence of attractive charge-charge interactions between the two reactants. Isothermal titration calorimetry showed that GALDH weakly interacts with both oxidized and reduced Cc. Chemical shift perturbations for (1) H and (15) N nuclei of Cc, arising from the interactions with unlabeled GALDH, were used to map the interacting surface of Cc. For Arabidopsis Cc and yeast Cc, similar residues are involved in the interaction with GALDH. These residues are confined to a single surface surrounding the heme edge. The range of chemical shift perturbations for the physiological Arabidopsis Cc-GALDH complex is larger than that of the non-physiological yeast Cc-GALDH complex, indicating that the former complex is more specific. In summary, the results point to a relatively low affinity GALDH-Cc interaction, similar for all partner redox states, involving protein-protein dynamic motions. Evidence is also provided that Cc utilizes a conserved surface surrounding the heme edge for the interaction with GALDH and other redox partners.

Introducción: La malnutrición en los pacientes hospitalizados tiene implicaciones clínicas y evolutivas, por lo que existe interés en desarrollar métodos de cribado que identifiquen los individuos de riesgo. En la actualidad no existe consenso acerca de la herramienta de cribado nutricional más apropiada para aplicar en población pediátrica. Objetivo: Validar en España la herramienta de cribado nutricional pediátrico STAMP (Screening Tool for the Assessment of Malnutrition in Pediatrics). Métodos: Estudio descriptivo transversal en pacientes ingresados en un hospital pediátrico de tercer nivel con diferentes especialidades médicas y quirúrgicas. En las primeras 24 horas de ingreso se aplicó el método de cribado nutricional STAMP. Para la validación de sus resultados se llevó a cabo una valoración del estado nutricional que incluyó datos clínicos, antropométricos y de composición corporal realizada por personal especializado en nutrición. Resultados: Fueron estudiados 250 niños. La valoración nutricional detectó 64 pacientes (25,6%) considerados de riesgo, de los cuales 40 (16%) estaban ya malnutridos. STAMP clasificó un 48,4% de la muestra como de riesgo nutricional elevado. Dicho método mostró una sensibilidad del 75% y una especificidad del 60,8% para identificar los pacientes considerados de riesgo en la valoración nutricional, y una sensibilidad del 90% y especificidad del 59,5% para detectar los malnutridos. Comentarios: La frecuencia de malnutrición fue algo inferior a la de otros países de nuestro entorno, aunque el método diagnóstico fue diferente. El método STAMP es una herramienta sencilla y útil para el cribado nutricional, que evitaría la necesidad de valorar a todos los pacientes al ingreso para detectar los sujetos de riesgo. Background: Malnutrition among hospitalized patients has clinical implications, and interest has arisen to find screening tools able to identify subjects under risk. At present, there is no consensus about the most suitable nutrition screening tool for pediatric patients. Aim: To validate STAMP (Screening Tool for the Assessment of Malnutrition in Pediatrics) pediatric screening tool in Spain. Methods: Descriptive cross-sectional study of patients admitted to a 3rd level children's hospital with both medical and surgical specialities. During the first 24 hours of admission, STAMP screening tool was applied. For its validation, results were compared with those obtained from a nutritional assessment performed by specialist staff, which included clinical, anthropometric and body composition data. Results: A sample of 250 children was studied. Nutritional assessment identified 64 patients (25.6%) under risk, 40 of whom were malnourished (16%). STAMP classified 48.4% of the patients as being under nutritional risk. This tool showed 75% sensitivity and 60.8% specificity when identifying patients under risk according to nutritional assessment. It showed 90% sensitivity and 59.5% specificity when identifying malnourished patients. Comments: Malnutrition was less frequent than that reported in other European countries, although diagnosis technique was different. STAMP is a simple and useful tool for nutritional screening, avoiding the need to assess all patients on admission in order to identify those under nutritional risk.

This work is an historical survey of the medical usages of mineral springs in Spain. From old times to nowadays, the therapeutic employs of these waters used for bathing or in oral administrations in order to cure different diseases, are described. Though the different periods of time reference is made to the main Spas, illnesses to heal, physicians, pharmacists, analysts and writers that focused on these aspects as well as other social and scientific subjects. Este trabajo es un recorrido histórico del uso medicinal de las aguas minerales en España. En él se describe la utilización terapéutica de las aguas en forma de baños o por via oral para curar diversas enfermedades, desde la antiguedad hasta nuestros días. En las distintas épocas se hace referencia a los principales balnearios, las enfermedades que se trataban, los médicos, farmacéuticos, analistas y escritores que se ocuparon de este tema así como otros aspectos sociales y científicos.

Interstitial deletions of the long arm of chromosome 12 are rare, with a dozen patients carrying a deletion in 12q21 being reported. Recently a critical region (CR) has been delimited and could be responsible for the more commonly described clinical features, such as developmental delay/intellectual disability, congenital genitourinary and brain malformations. Other, less frequent, clinical signs do not seem to be correlated to the proposed CR. We present seven new patients harboring non-recurrent deletions ranging from 1 to 18.5 Mb differentially scattered across 12q21. Alongside more common clinical signs, some patients have rarer features such as heart defects, hearing loss, hypotonia and dysmorphisms. The correlation of haploinsufficiency of genes outside the CR to specific signs contributes to our knowledge of the effect of the deletion of this gene-poor region of chromosome 12q. This work underlines the still important role of copy number variations in the diagnostic setting of syndromic patients and the positive reflection on management and family genetic counseling.