Compromiso nodal y extranodal detectado con PET/CT en linfoma en etapificación / Nodal and extranodal involvement detected by PET/CT in staging lymphoma

Objective: To describe visible nodal and extra-nodal involvement using PET/CT in the different types and subtypes of lymphoma in staging. Patients and method: PET/CT with F18-FDG were reviewed in patients with lymphoma staging, determining frequency and location of nodal and extra-nodal involvement, and intensity of F18-FDG uptake measured by SUVmax. Results: Of the 102 patients with NHL (average SUVmax 13.0 ± 9.7), 86.3% had nodal involvement (51.9% on both sides of the diaphragm, 24.5% only above the diaphragm), and 66.7% extra-nodal compromise (42.6% bone marrow, 22.1% muscle, 16.2% renal). Of the 30 patients with HL (average SUVmax 14.6 ± 6.0), 100% had nodal involvement (63.3% only above the diaphragm, 36.7% above and below the diaphragm), and 30% had extra-nodal involvement (66.7% bone marrow, 22.2% lung). Conclusion: PET/CT is the method of choice in the staging of lymphoma, allowing the detection of nodal and extra-nodal disease in both HL and NHL.

Objetivo: Describir el compromiso nodal y extranodal visible con PET/CT en los distintos tipos y subtipos de linfoma en etapificación. Pacientes y método: Se revisaron los PET/CT con F18-FDG realizados a pacientes con linfoma en etapificación, determinando frecuencia y localización del compromiso nodal y extranodal, e intensidad de captación de F18-FDG medida mediante SUVmax. Resultados: De los 102 pacientes con LNH (SUVmaxpromedio 13,0±9,7), un 86,3% presentó compromiso nodal (51,9% a ambos lados del diafragma, 24,5% sólo sobre el diafragma) y 66,7% compromiso extranodal (42,6% médula ósea, 22,1% muscular, 16,2% renal). De los 30 pacientes con LH (SUVmax promedio 14,6±6,0), el 100% tuvo compromiso nodal (63,3% sólo sobre el diafragma, 36,7% sobre y bajo el diafragma), y 30% compromiso extranodal (66,7% médula ósea, 22,2% pulmón). Conclusión: El PET/CT es el método de elección en la etapificación del linfoma, permitiendo detectar enfermedad nodal y extranodal, tanto en LH como en LNH.

Validación de la escala de autoeficacia general en Chile / General self-effcacy scale validation in Chile

Background: Self effcacy refers to an individual’s belief in his or her capability to produce given achievements and the individual’s perception of his or her ability to perform an action. Aim: To evaluate the psychometric properties of the General Self-effcacy Scale in Chilean population. Material and Methods: The study was carried out in 360 subjects, both sexes, 15-65 years of age, from Concepción, Chile, who answered Self-efficacy, Self-esteem and Health Status Perception instruments. Reliability was verified by Cronbach’s alpha coefficient and validity by expert re-vision, univariate statistics, correlations among items, item-scale correlations, and correlations with Self-esteem and Perception of Health Status constructs. Results: The structure of the scale is uni-dimensional, homogenous and positively related with the constructs examined. Conclusions: The General Self-efficacy Scale is a reliable and valid measure of the perception of self-efficacy in the Chilean population.

Agresión y violencia en la escuela como factor de riesgo del aprendizaje escolar / Aggression and violence in school as a risk factor of school education

Un problema actual y creciente de salud en la comunidad escolar es la agresión y violencia observada entre los estudiantes, siendo de tal intensidad que ha provocado incidentes negativos en niños y adolescentes, como dificultad en el aprendizaje y abandono escolar, observándose esta problemática transversalmente en diversos contextos culturales y sociales. Esta revisión bibliográfica tiene como objetivo apreciar cómo se da la agresión y violencia entre los escolares, los factores que están involucrados en estos eventos, así como también identificar algunas intervenciones que se han llevado a cabo para prevenir y tratar estas conductas, y los resultados obtenidos. Dentro de los factores que se relacionan con la agresión escolar están los de tipo individual, familiar, escolar y del ambiente. Las intervenciones realizadas han tenido como foco a los padres, profesores y/o alumnos(as), obteniéndose resultados positivos en aquellas con enfoque integral.

A current problem and increasing health in the school community is the observed aggression and violence among students, being of such intensity that has led to adverse incidents in children and adolescents, such a difficulty in learning and school dropout, having this problem across various cultural and social contexts. This bibliographical revisión has the objective to appreciate how the aggression and violence occurs among students,the factors that are involved in these events, as well as to indentify some interventios that have been carried out to prevent and treat these conducís and results. Within the factors that are related with the school aggression are: those of individual type, familiar, school activities and school atmosphere. The interventions made the parents responsibles, teachers and students in general, the results of these objectives has been positive.

Factores biológicos y psicosociales predictores del estilo de vida promotor de salud / Biological and psychosocial factors that predict health promoting lifestyles

Background: One of the goals of the national health reform is to promote a healthy lifestyle in all the population. The determinants of healthy lifestyles need to be identified to guide people towards this purpose. Aim: To analyze the health promoting lifestyle (HLP) in a community of Concepción and to identify the personal factors that might be predictors of such lifestyle. Material and methods: Pender's health promotion model was used as the conceptual framework for exploring the HLP among 360 persons aged from 15 to 64 years, free from chronic diseases. Data were obtained by a semi structured questionnaire and the following scales were used to measure HLP: perceived health status, perceived self esteem, and perceived self efficacy. Relationships between personal factors and HLP were studied. Data were processed with SAS software and analyzed with descriptive and inferential statistics. Results: Only 52.2 percent of the sample had a healthy lifestyle. The variables sex, age, occupation, access to health care, self esteem, perceived health status and perceived self efficacy had a significant effect on HLP. A regression model showed that self esteem, self efficacy, sex, age, occupation and access to health care explained 30 percent of the variation in health lifestyle. Conclusions: Only half of the studied sample had a healthy lifestyle. The variables obtained with the regression model, should be considered to create effective interventions encouraging persons to integrate healthy behaviors to their life.

Interactions that regulate the helical fold in proteins

Several factors that may contribute to the stabilization of the helical structure in proteins, detected in studies made on short synthetic peptides, have been reported. Some of them are: presence of alanine or leucine, ionic-pair bonding, stabilization of the helical dipole moment by appropriate charges at the helix N- and C-caps, and aromatic interactions of amino acids located at positions i, i + 4. An analysis of 54 helical structures from 12 proteins showed that all these stabilizing factors were also present in proteins, but the influence of any of them had a different weight, according to the distribution of the hydrophobic and hydrophilic amino acid residues in the helical sequence. The role of non-sequence depending interactions in helical stability, such as presence of disulfide bridges, or bonding of helical residues to substrate and/or cofactors, was also analysed

Active-site studies of enzymes by X-ray diffraction methods

X-Ray diffraction is the only method currently available for the determination of the detailed three-dimensional structure of macromolecules. In this article, the principles behind the use of X-ray crystallography in the study of protein structure are presented. The results obtained in its application to several enzymes are discussed, as well as the limitations of the method

Active-site studies of enzymes by secondary structure prediction and by molecular modeling

Since the determination of the tertiary structure by X-ray crystallography has been achieved only for a limited number of proteins, alternative approaches are being sought. In this article, the use of secondary structure prediction and of molecular modeling is discussed. Several examples are analyzed in detail