Estudio de la prevalencia del riesgo de desnutrición en la población mayor de 65 años no institucionalizada atendida en un centro de salud de Barcelona / Study of the prevalence of the risk of malnutrition in the non-institutionalized population over 65 years old attended in a health center in Barcelona

Objetivo: Conocer la prevalencia del riesgo de desnutrición de la población mayor de 65años no institucionalizada, atendida en un centro de salud, y evaluar la versión corta frente a la versión larga del test Mini Nutritional Assessment (MNA) y conocer los factores relacionados con el riesgo de desnutrición. Método: Estudio descriptivo transversal en un equipo de atención primaria de salud en ámbito urbano. Participaron 337 pacientes mayores de 65años atendidos en el centro. La recogida de datos se hizo mediante entrevista personalizada y revisión de la historia clínica. Se administró el MNA (versión corta [MNA-SF] +texto completo [MNA-FT]) y se recogieron variables sociodemográficas y de evaluación funcional (test cognitivos de Pfeiffer y de Lawton y Brody sobre actividades instrumentales de la vida diaria (AIVD) y antecedentes clínicos. Utilizando MNA-FT como gold standard se evaluó la sensibilidad, la especificidad y los valores predictivos de MNA-SF. Los participantes fueron informados de los objetivos del estudio y firmaron el consentimiento informado. El estudio obtuvo el visto bueno del Comité de Ética de referencia. Resultados: Según el MNA-FT la prevalencia fue del 0,6% de desnutrición y del 7,7% de riesgo, sin diferencias según el sexo. La media de edad era superior en los pacientes con desnutrición o riesgo de ella (p=0,016). Se relacionaba con desnutrición tener cuidador (p<0,0001) o mayor grado de dependencia (p<0,0001). El MNA-SF mostró aceptable sensibilidad (67,9%) y buena especificidad (92,6%). Conclusiones: Se observó una baja prevalencia de riesgo de desnutrición entre los pacientes ambulatorios mediante el test MNA. Se recomienda el uso del MNA-FT dada la mejorable sensibilidad mostrada por el MNA-SF, evitando así el consecuente infradiagnóstico. Pacientes con cuidador, mayor dependencia y edad tienen más probabilidad de peor estado nutricional.(AU)

Objective: To know the prevalence of risk of malnutrition in community-dwelling elderly (defined as aged >65) attended in a Primary Care Center, to find the main factors associated to malnutrition risk and to evaluate the Mini Nutritional Assessment Questionnaire (MNA) MNA Short Form vs. MNA Full Test. Method: Design: Cross-Sectional study. Setting: Primary Care Center. Subjects: 337 participants visited in the Community Care Center. Mini Nutritional Assessment Questionnaire (MNA) was applied; sociodemographic and Health variables were collected as well as functional evaluation tests (Short Portable Mental Status Questionnaire and Lawton & Brody Instrumental Activities of Daily Living Scale). Clinical history information was taken from the Medical Records. Using MNA Full Test (MNA-FT) as the gold standard, sensitivity, specificity and predictive values of MNA Short Form (MNA-SF) were evaluated. Results: prevalence according MNA-FT was 0.6% for malnutrition and 7.7% for malnutrition risk. No gender differences were found. The average age was higher in the population with malnutrition or at risk for malnutrition (p=0.016). Significant association of malnutrition with having carer (p<0.0001) or being more dependent (p<0.0001) was found. MNA-SF showed an acceptable sensitivity (67.9%) and good specificity (92.6%). Conclusions: Compared with other studies this data showed a low prevalence of malnutrition risk in community-living elderly using the MNA test. It is recommended to use the MNA-FT in order to avoid under diagnosing malnutrition with MNA-SF.(AU)

Study of the prevalence of the risk of malnutrition in the non-institutionalized population over 65 years old attended in a health center in Barcelona. / Estudio de la prevalencia del riesgo de desnutrición en la población mayor de 65 años no institucionalizada atendida en un centro de salud de Barcelona.

OBJECTIVE: To know the prevalence of risk of malnutrition in community-dwelling elderly (defined as aged >65) attended in a Primary Care Center, to find the main factors associated to malnutrition risk and to evaluate the Mini Nutritional Assessment Questionnaire (MNA) MNA Short Form vs. MNA Full Test. METHOD: Design: Cross-Sectional study. SETTING: Primary Care Center. SUBJECTS: 337 participants visited in the Community Care Center. Mini Nutritional Assessment Questionnaire (MNA) was applied; sociodemographic and Health variables were collected as well as functional evaluation tests (Short Portable Mental Status Questionnaire and Lawton & Brody Instrumental Activities of Daily Living Scale). Clinical history information was taken from the Medical Records. Using MNA Full Test (MNA-FT) as the gold standard, sensitivity, specificity and predictive values of MNA Short Form (MNA-SF) were evaluated. RESULTS: prevalence according MNA-FT was 0.6% for malnutrition and 7.7% for malnutrition risk. No gender differences were found. The average age was higher in the population with malnutrition or at risk for malnutrition (p=0.016). Significant association of malnutrition with having carer (p<0.0001) or being more dependent (p<0.0001) was found. MNA-SF showed an acceptable sensitivity (67.9%) and good specificity (92.6%). CONCLUSIONS: Compared with other studies this data showed a low prevalence of malnutrition risk in community-living elderly using the MNA test. It is recommended to use the MNA-FT in order to avoid under diagnosing malnutrition with MNA-SF.

Informed consent: A study of patients with life-threatening illnesses.

BACKGROUND: The relationship between healthcare professionals and patients in the Spanish health sector has undergone dramatic change. One aspect of this is that the use of informed consent has become a key factor in the delivery of adequate healthcare. But although a certain period of time has already passed since informed consent started to be used, in Spain there is still doubt about how adequately informed consent is being used. OBJECTIVES: (a) To look at how patients understand the notion and purpose of informed consent, and (b) how the informed consent is applied - the way patients receive such information affects their level of participation and decision making during the time they receive medical care. METHODOLOGY: We use interpretative description of interviews with patients. We developed guiding questions for the interviews with patients in two preliminary and exploratory focus groups. Then, we carried out 20 personal open-ended interviews with 20 purposive selected patients with illnesses that had a serious impact on their lives. Ethical considerations: Permission from ethical committees and institutions involved in the study, and consent and confidentiality were ensured before conducting the research. RESULTS: The findings show that while patients agreed that their consent should be necessary for health professionals to be able to intervene, they had serious difficulty obtaining and then understanding information offered to them at the moment when they were being asked to sign informed consent documents. The participants were critical of the consent documents, which they considered were treated as merely a formality and even some of them had felt coerced to sign. DISCUSSION: Participants confirmed that the informed consent documents that they signed did not meet their ethical objectives. Their perception of the purpose of consent indicates that informed consent document may still be largely understood as a formality rather an ethical obligation.

Structure and interaction with phospholipids of a prokaryotic lipoxygenase from Pseudomonas aeruginosa.

Lipoxygenases (LOXs), which are essential in eukaryotes, have no confirmed function in prokaryotes that are devoid of polyunsaturated fatty acids. The structure of a secretable LOX from Pseudomonas aeruginosa (Pa_LOX), the first available from a prokaryote, presents significant differences with respect to eukaryotic LOXs, including a cluster of helices acting as a lid to the active center. The mobility of the lid and the structural variability of the N-terminal region of Pa_LOX was confirmed by comparing 2 crystal forms. The binding pocket contains a phosphatidylethanolamine phospholipid with branches of 18 (sn-1) and 14/16 (sn-2) carbon atoms in length. Carbon atoms from the sn-1 chain approach the catalytic iron in a manner that sheds light on how the enzymatic reaction might proceed. The findings in these studies suggest that Pa_LOX has the capacity to extract and modify unsaturated phospholipids from eukaryotic membranes, allowing this LOX to play a role in the interaction of P. aeruginosa with host cells.

Bacterial lipoxygenases, a new subfamily of enzymes? A phylogenetic approach.

Lipoxygenases (EC. 1.13.11.12) are a non-heme iron enzymes consisting of one polypeptide chain folded into two domains, the N-terminal domain and the catalytic moiety ß-barrel domain. They catalyze the dioxygenation of 1Z,4Z-pentadiene moieties of polyunsaturated fatty acids obtaining hydroperoxy fatty acids. For years, the presence of lipoxygenases was considered a eukaryotic feature, present in mammals, plants, small marine invertebrates, and fungi, but now, some lipoxygenase sequences have been detected on prokaryotic organisms, changing the idea that lipoxygenases are exclusively a eukaryotic affair. Lipoxygenases are involved in different types of reactions on eukaryote organisms where the biological role and the structural characteristics of these enzymes are well studied. However, these aspects of the bacterial lipoxygenases have not yet been elucidated and are unknown. This revision discusses biochemical aspects, biological applications, and some characteristics of these enzymes and tries to determine the existence of a subfamily of bacterial lipoxygenases in the context of the phylogeny of prokaryotic lipoxygenases, supporting the results of phylogenetic analyzes with the comparison and discussion of structural information of the first prokaryotic lipoxygenase crystallized and other eukaryotic lipoxygenases structures.

Functional characterization of ExFadLO, an outer membrane protein required for exporting oxygenated long-chain fatty acids in Pseudomonas aeruginosa.

Bacterial proteins of the FadL family have frequently been associated to the uptake of exogenous hydrophobic substrates. However, their outer membrane location and involvement in substrate uptake have been inferred mainly from sequence similarity to Escherichia coli FadL, the first well-characterized outer membrane transporters of Long-Chain Fatty Acids (LCFAs) in bacteria. Here we report the functional characterization of a Pseudomonas aeruginosa outer membrane protein (ORF PA1288) showing similarities to the members of the FadL family, for which we propose the name ExFadLO. We demonstrate herein that this protein is required to export LCFAs 10-HOME and 7,10-DiHOME, derived from a diol synthase oxygenation activity on oleic acid, from the periplasm to the extracellular medium. Accumulation of 10-HOME and 7,10-DiHOME in the extracellular medium of P. aeruginosa was abolished by a transposon insertion mutation in exFadLO (ExFadLO¯ mutant). However, intact periplasm diol synthase activity was found in this mutant, indicating that ExFadLO participates in the export of these oxygenated LCFAs across the outer membrane. The capacity of ExFadLO¯ mutant to export 10-HOME and 7,10-DiHOME was recovered after complementation with a wild-type, plasmid-expressed ExFadLO protein. A western blot assay with a variant of ExFadLO tagged with a V5 epitope confirmed the location of ExFadLO in the bacterial outer membrane under the experimental conditions tested. Our results provide the first evidence that FadL family proteins, known to be involved in the uptake of hydrophobic substrates from the extracellular environment, also function as secretion elements for metabolites of biological relevance.

Precursor uptake assays and metabolic analyses in isolated tomato fruit chromoplasts.

BACKGROUND: Carotenoids are the most widespread group of pigments found in nature. In addition to their role in the physiology of the plant, carotenoids also have nutritional relevance as their incorporation in the human diet provides health benefits. In non-photosynthetic tissues, carotenoids are synthesized and stored in specialized plastids called chromoplasts. At present very little is known about the origin of the metabolic precursors and cofactors required to sustain the high rate of carotenoid biosynthesis in these plastids. Recent proteomic data have revealed a number of biochemical and metabolic processes potentially operating in fruit chromoplasts. However, considering that chloroplast to chromoplast differentiation is a very rapid process during fruit ripening, there is the possibility that some of the proteins identified in the proteomic analysis could represent remnants no longer having a functional role in chromoplasts. Therefore, experimental validation is necessary to prove whether these predicted processes are actually operative in chromoplasts. RESULTS: A method has been established for high-yield purification of tomato fruit chromoplasts suitable for metabolic studies. Radiolabeled precursors were efficiently incorporated and further metabolized in isolated chromoplast. Analysis of labeled lipophilic compounds has revealed that lipid biosynthesis is a very efficient process in chromoplasts, while the relatively low incorporation levels found in carotenoids suggest that lipid production may represent a competing pathway for carotenoid biosynthesis. Malate and pyruvate are efficiently converted into acetyl-CoA, in agreement with the active operation of the malic enzyme and the pyruvate dehydrogenase complex in the chromoplast. Our results have also shown that isolated chromoplasts can actively sustain anabolic processes without the exogenous supply of ATP, thus suggesting that these organelles may generate this energetic cofactor in an autonomous way. CONCLUSIONS: We have set up a method for high yield purification of intact tomato fruit chromoplasts suitable for precursor uptake assays and metabolic analyses. Using targeted radiolabeled precursors we have been able to unravel novel biochemical and metabolic aspects related with carotenoid and lipid biosynthesis in tomato fruit chromoplasts. The reported chromoplast system could represent a valuable platform to address the validation and characterization of functional processes predicted from recent transcriptomic and proteomic data.

Cloning and expression of a lipoxygenase from Pseudomonas aeruginosa 42A2.

In order to produce (S) 10-monohydroxy-8E-octadecenoic acid (MHOD) from oleic acid, a full-length probable lipoxygenase cDNA from Pseudomonas aeruginosa 42A2 was cloned and expressed in Escherichia coli BL21(DE3). The recombinant protein was purified by affinity chromatography to electrophoretic homogeneity and specifically stained. Its molecular mass was 70 kDa. The activity of the rec-LOX with oleic acid was about 30% of that of the preferred substrate, linoleic acid (100%). Bacterial LOX forms a new subfamily in the lipoxygenase phylogenetic tree.