Germline variants in early and late-onset Brazilian prostate cancer patients.

BACKGROUND: The median age for Prostate Cancer (PCa) diagnosis is 66 years, but 10% are diagnosed before 55 years. Studies on early-onset PCa remain both limited and controversial. This investigation sought to identify and characterize germline variants within Brazilian PCa patients classified as either early or later onset disease. METHODS: Peripheral blood DNA from 71 PCa patients: 18 younger (≤ 55 years) and 53 older (≥ 60 years) was used for Targeted DNA sequencing of 20 genes linked to DNA damage response, transcriptional regulation, cell cycle, and epigenetic control. Subsequent genetic variant identification was performed and variant functional impacts were analyzed with in silico prediction. RESULTS: A higher frequency of variants in the BRCA2 and KMT2C genes across both age groups. KMT2C has been linked to the epigenetic dysregulation observed during disease progression in PCa. We present the first instance of KMT2C mutation within the blood of Brazilian PCa patients. Furthermore, out of the recognized variants within the KMT2C gene, 7 were designated as deleterious. Thirteen deleterious variants were exclusively detected in the younger group, while the older group exhibited 37 variants. Within these findings, 4 novel variants emerged, including 1 designated as pathogenic. CONCLUSIONS: Our findings contribute to a deeper understanding of the genetic factors associated with PCa susceptibility in different age groups, especially among the Brazilian population. This is the first investigation to explore germline variants specifically in younger Brazilian PCa patients, with high relevance given the genetic diversity of the population in Brazil. Additionally, our work presents evidence of functionally deleterious germline variants within the KMT2C gene among Brazilian PCa patients. The identification of novel and functionally significant variants in the KMT2C gene emphasizes its potential role in PCa development and warrants further investigation.

Percepção de risco, efeitos psicológicos e apoio social em profissionais de saúde com pacientes com COVID-19 no México / Risk perception, psychological effects, and social support in health care workers with COVID-19 patients in Mexico / Percepción de riesgo, efectos psicológicos y apoyo social en trabajadores sanitarios con pacientes con COVID-19 en México

Resumo Objetivo: identificar a associação entre percepção de risco e vários efeitos psicológicos negativos e positivos, bem como o efeito moderador do apoio social, em uma amostra de trabalhadores de saúde com pacientes com COVID-19 no México. Métodos: trata-se de um desenho ex-post-facto e instrumental. As respostas foram obtidas por meio de questionário on-line , utilizando a estratégia de bola de neve. A associação entre percepção de risco e vários resultados psicológicos foi examinada por meio de correlações monotônicas (Spearman, rs), e um modelo de regressão foi estimado para cada efeito psicológico a fim de testar o efeito moderador do apoio social. Resultados: participaram 269 trabalhadores da saúde, sendo 75,5% mulheres. Os achados mostram a percepção de risco com uma tendência elevada, especialmente em relação ao "risco de dano grave pelo SARS-CoV-2". O apoio social apresentou uma tendência de moderada a alta, e os sintomas negativos de saúde mental tiveram uma tendência abaixo das médias teóricas. Conclusão: o apoio social desempenha papel moderador na magnitude da associação entre a percepção de risco e os efeitos psicológicos. Apesar das limitações reconhecidas, este trabalho visa ajudar a explicar os mecanismos complexos das variáveis em estudo por meio da análise exploratória de interações.

Abstract Objective: to identify the association between risk perception and various negative and positive psychological effects, as well as the moderating effect of social support, in a sample of health care workers with COVID-19 patients in Mexico. Methods: this study has an ex post facto and instrumental design. Responses were obtained by means of an online survey using snowball convenience sampling. The association of risk perception with various psychological outcomes was examined using monotonic correlations (Spearman, rs), and a regression model was estimated for each psychological effect to test the moderating effect of social support. Results: a total of 269 health care workers took part, 75.5% of them women. The findings show that risk perception tended to be high, especially in relation to the "risk of serious harm from SARS-CoV-2". Social support had a moderate to high trend, and negative mental health symptoms had a trend below theoretical average points. Conclusion: social support plays a moderating role in the magnitude of the association between risk perception and psychological effects. Despite the acknowledged limitations, this work aimed to help explain the complex mechanisms of the study variables by analyzing exploratory interactions.

Resumen Objetivo: identificar la asociación entre percepción de riesgo y diversos efectos psicológicos negativos y positivos, así como el efecto moderador del apoyo social, en una muestra de trabajadores sanitarios con pacientes COVID-19 en México. Métodos: se trató de un diseño ex post facto e instrumental. Se obtuvieron respuestas por medio de un cuestionario en línea mediante la estrategia de bola de nieve. Se examinó la asociación de la percepción de riesgo con varios resultados psicológicos mediante correlaciones monotónicas (Spearman, rs), y se estimó un modelo de regresión para cada efecto psicológico para probar el efecto moderador del apoyo social. Resultados: participaron 269 trabajadores sanitarios, de los cuales un 75,5% eran mujeres. Los hallazgos muestran una percepción de riesgo con tendencia elevada, particularmente la relacionada al "riesgo de daño grave por SARS-CoV2", el apoyo social tuvo una tendencia de moderada a alta y los síntomas negativos de salud mental tuvieron una tendencia por debajo de los promedios teóricos. Conclusión: el apoyo social juega un papel moderador en la magnitud de asociación entre percepción de riesgo y efectos psicológicos. A pesar de las limitaciones reconocidas, este trabajo pretende ayudar a explicar los mecanismos complejos de las variables de estudio mediante el análisis de interacciones exploratorias.

Psychometric Validity of the Areas of Work Life Scale (AWS) in Teachers and Healthcare Workers in México.

The areas of work life scale (AWS) has shown to be a suitable marker of perceived fit between employees' abilities and the psychosocial demands of the job, but validation studies are practically nonexistent in the Latino population. The purpose of this study was twofold: firstly, to examine the factor structure, reliability, and invariance between sex and occupation of the AWS scale, and secondly, to test the AWS-burnout relationship within the framework of the structural mediational model proposed by Leiter and Maslach (2005). N = 305 health workers and N = 324 teachers from different work settings answered the AWS and MBI-GS scales. In this study, 64.4% of the participants were females (N = 405), and the mean age was 34.7 (sd = 11.7, rank = 56). Robust methods for statistical analyses were used. The results showed that the original version had marginal fit indices due to a method effect (negative phrasing items), and when seven negative items were removed, a final best model was found (CFI = 0.997; RMSEA = 0.060; SRMRu = 0.047). Non-invariance between occupation and sex was found, and the internal consistency was from marginal to satisfactory (ω = 0.658 to 0.840). The mediational structural model tested confirmed the expected associations between AWS and burnout. In conclusion, the Mexican translation of the AWS in its 22-reduced version showed reliability and validity in Mexican work contexts, specifically in healthcare workers and teachers.

Brief Sensations Seeking Scale (BSSS): Validity Evidence in Mexican Adolescents.

Sensation seeking is a construct associated with risky behaviors over a wide age range, but validation studies in Mexico are lacking. The aim of this study was to investigate the validity of two versions of the Brief Sensation Seeking Scale (the BSSS-8 and BSSS-4) in young Mexican individuals. The sample consisted of 2884 students (age: M = 16.6, SD = 1.5) from five preparatory schools in Morelos, Mexico. The internal structure of the BSSS was evaluated according to the structural equation modeling (SEM) parameterization, including measurement invariance (compared to the factor loadings obtained in the meta-analysis); conditional reliability; and equivalence between versions. The unidimensionality and measurement invariance (configurational, factor loadings, thresholds, intercepts, and residuals) across sex and age groups were satisfactory, and the factor loadings were highly congruent with those obtained in the meta-analysis. Reliability was suitably high (greater than 0.80), especially near the mean scores, but was lower for extreme scores. Thus, the instrument was concluded to be optimal for defining the construct of sensation seeking, consistent with the findings of previous studies.

Malnutrition Rates in Chile from the Nitrate Era to the 1990s.

Following Salvatore and the WHO, in this article, we provide the first long-term estimates of malnutrition rates for Chile per birth cohort, measured through stunting rates of adult males born from the 1870s to the 1990s. We used a large sample of military records, representative of the whole Chilean population, totalling over 38 thousand individuals. Our data suggest that stunting rates were very high for those born between the last three decades of the nineteenth century and the first two decades of the twentieth century. In addition, stunting rates increased from the 1870s to the 1900s. Thereafter, there was a clear downward trend in stunting rates (despite some fluctuations), reaching low levels of malnutrition, in particular, from the 1960s (although these are high if compared to developed countries). The continuous decrease in stunting rates from the 1910s was mainly due to a combination of factors, the importance of which varied over time, namely: Improved health (i.e., sharp decline in infant mortality rates during the whole period); increased energy consumption (from the 1930s onwards, but most importantly during the 1990s); a decline in poverty rates (in particular, between the 1930s and the 1970s); and a reduction in child labour (although we are less able to quantify this).

[General and infant mortality trends in Chile from 1909 to 2017]. / Mortalidad general e infantil en Chile en el largo plazo, 1909-2017.

BACKGROUND: During the twentieth century, Chile experienced an important reduction in general mortality. AIM: To describe both general and infant mortality of Chile from 1909 to 2017. MATERIAL AND METHODS: Analysis of information about births and deaths published by the Chilean National Institute of Statistics for the period between 1909 and 2017. RESULTS: Both general and infant mortality rates declined sharply from the 1930s to the late 1990s. However, during the last few years, general mortality rates increased slightly. This is the first increase in over a century. Another positive aspect is that there was a dramatic decrease in mortality rate gaps across Chilean regions, for both general and infant mortality. However, intraregional inequalities in infant mortality continue to be a detrimental factor. CONCLUSIONS: Public health efforts should be carried out to further reduce socioeconomic and regional gaps in adult and infant mortality in Chile.

Mortalidad general e infantil en Chile en el largo plazo, 1909-2017 / General and infant mortality trends in Chile from 1909 to 2017

Background: During the twentieth century, Chile experienced an important reduction in general mortality. Aim: To describe both general and infant mortality of Chile from 1909 to 2017. Material and Methods: Analysis of information about births and deaths published by the Chilean National Institute of Statistics for the period between 1909 and 2017. Results: Both general and infant mortality rates declined sharply from the 1930s to the late 1990s. However, during the last few years, general mortality rates increased slightly. This is the first increase in over a century. Another positive aspect is that there was a dramatic decrease in mortality rate gaps across Chilean regions, for both general and infant mortality. However, intraregional inequalities in infant mortality continue to be a detrimental factor. Conclusions: Public health efforts should be carried out to further reduce socioeconomic and regional gaps in adult and infant mortality in Chile.

Height of Male Prisoners in Santiago de Chile during the Nitrate Era: The Penalty of being Unskilled, Illiterate, Illegitimate and Mapuche.

This article contributes to the study of inequality in the biological welfare of Chile's adult population during the nitrate era, ca. 1880s-1930s, and in particular focuses on the impact of socioeconomic variables on height, making use of a sample of over 20,000 male inmates of the capital's main jail. It shows that inmates with a university degree were taller than the rest; that those born legitimate were taller in adulthood; that those (Chilean born) whose surnames were Northern European were also taller than the rest, and in particular than those with Mapuche background; and that those able to read and write were also taller than illiterate inmates. Conditional regression analysis, examining both correlates at the mean and correlates across the height distribution, supports these findings. We show that there was more height inequality in the population according to socioeconomic status and human capital than previously thought, while also confirming the importance of socioeconomic influences during childhood on physical growth.

Exomes of Ductal Luminal Breast Cancer Patients from Southwest Colombia: Gene Mutational Profile and Related Expression Alterations.

Cancer is one of the leading causes of mortality worldwide. Breast cancer is the most frequent cancer in women, and in recent years it has become a serious public health problem in Colombia. The development of large-scale omic techniques allows simultaneous analysis of all active genes in tumor cells versus normal cells, providing new ways to discover the drivers of malignant transformations. Whole exome sequencing (WES) was obtained to provide a deep view of the mutational genomic profile in a set of cancer samples from Southwest Colombian women. WES was performed on 52 tumor samples from patients diagnosed with invasive breast cancer, which in most cases (33/52) were ductal luminal breast carcinomas (IDC-LM-BRCA). Global variant call was calculated, and six different algorithms were applied to filter out false positives and identify pathogenic variants. To compare and expand the somatic tumor variants found in the Colombian cohort, exome mutations and genome-wide expression alterations were detected in a larger set of tumor samples of the same breast cancer subtype from TCGA (that included DNA-seq and RNA-seq data). Genes with significant changes in both the mutational and expression profiles were identified, providing a set of genes and mutations associated with the etiology of ductal luminal breast cancer. This set included 19 single mutations identified as tumor driver mutations in 17 genes. Some of the genes (ATM, ERBB3, ESR1, TP53) are well-known cancer genes, while others (CBLB, PRPF8) presented driver mutations that had not been reported before. In the case of the CBLB gene, several mutations were identified in TCGA IDC-LM-BRCA samples associated with overexpression of this gene and repression of tumor suppressive activity of TGF-ß pathway.

Far Lateral Approach for Resection of a Foramen Magnum Meningioma: 3-Dimensional Surgical Video.

We present the case of a meningioma of the foramen magnum, in a patient of age 62 yr, who presented at the time of surgery a hemiparesis on the right side at 2 mo of evolution. The patient gave his informed consent for the publication of the case, and approval was obtained from the research department of the hospital where the procedure was performed. The magnetic resonance imaging (MRI) in the mid-sagittal view shows a meningioma of the foramen magnum, with an extension in the posterior fossa and in the upper part of the cervical canal. In the coronal view and in the axial view, we can identify that although it is a meningioma of the anterior part of the foramen magnum, it is observed that the lesion has a displacement towards the right side. In a cadaveric specimen, we show the normal anatomy and the key landmarks for performing the approach. The patient was treated by a far lateral approach with a partial removal of the condyle. We show the craniectomy and the microsurgical technique for the tumor resection step by step. We paid particular attention in the anatomy surrounding the tumor and the tips and tricks for a safe resection. We reached a total resection with a good outcome; the result of the anatomopathological study confirmed the diagnosis of meningothelial meningioma. The dura was closed in a hermetic manner with a synthetic dura patch; then sealant was placed. The bone defect was corrected by placing a mesh in titanium. Then the flap was closed as usual. The patient has a good evolution with 1 yr of follow-up and without lesion in the control MRI.

Regulatory motifs found in the small heat shock protein (sHSP) gene family in tomato.

BACKGROUND: In living organisms, small heat shock proteins (sHSPs) are triggered in response to stress situations. This family of proteins is large in plants and, in the case of tomato (Solanum lycopersicum), 33 genes have been identified, most of them related to heat stress response and to the ripening process. Transcriptomic and proteomic studies have revealed complex patterns of expression for these genes. In this work, we investigate the coregulation of these genes by performing a computational analysis of their promoter architecture to find regulatory motifs known as heat shock elements (HSEs). We leverage the presence of sHSP members that originated from tandem duplication events and analyze the promoter architecture diversity of the whole sHSP family, focusing on the identification of HSEs. RESULTS: We performed a search for conserved genomic sequences in the promoter regions of the sHSPs of tomato, plus several other proteins (mainly HSPs) that are functionally related to heat stress situations or to ripening. Several computational analyses were performed to build multiple sequence motifs and identify transcription factor binding sites (TFBS) homologous to HSF1AE and HSF21 in Arabidopsis. We also investigated the expression and interaction of these proteins under two heat stress situations in whole tomato plants and in protoplast cells, both in the presence and in the absence of heat shock transcription factor A2 (HsfA2). The results of these analyses indicate that different sHSPs are up-regulated depending on the activation or repression of HsfA2, a key regulator of HSPs. Further, the analysis of protein-protein interaction between the sHSP protein family and other heat shock response proteins (Hsp70, Hsp90 and MBF1c) suggests that several sHSPs are mediating alternative stress response through a regulatory subnetwork that is not dependent on HsfA2. CONCLUSIONS: Overall, this study identifies two regulatory motifs (HSF1AE and HSF21) associated with the sHSP family in tomato which are considered genomic HSEs. The study also suggests that, despite the apparent redundancy of these proteins, which has been linked to gene duplication, tomato sHSPs showed different up-regulation and different interaction patterns when analyzed under different stress situations.

Diez años desde la implementación del RIS PACS de la Clínica Alemana de Santiago: impacto de la tomografía computarizada en el uso y disponibilidad de archivo / Ten years since the implementation of Clínica Alemana of Santiago's RIS PACS: the impact of computed tomography in the use and availability of storage

Abstract. RIS PACS systems have become indispensable for managing, distributing and archiving digital images. This study evaluated the impact of Computed Tomography in the Clínica Alemana of Santiago's PACS image service. The PACS database was reviewed using IMPAX BI software, and 2,267,683 studies between 2005 and 2014 were examined. Computed Tomography examinations made up 10.67% of the studies archived in PACS, but its weight in TB is 50.10% of the total. The impact of the studies of Computed Tomography were not properly dimensioned or anticipated, which has impacted on the expected availability for one year online studies. This study has adequately assessed the impact of Computed Tomography in PACS’ storage availability, and how it should be considered when planning the implementation of a PACS.

Resumen. Los sistemas RIS PACS se han vuelto indispensables para el manejo de las imágenes digitales, su distribución y archivo. Esta investigación evaluó el impacto de la tomografía computarizada en el PACS del servicio de imágenes de la Clínica Alemana de Santiago. Se revisó la base de datos del PACS a través de la herramienta de software IMPAX BI, de los 2.267.683 estudios del período 2005-2014. Los exámenes de tomografía computarizada representan el 10,67% de los estudios archivados en el PACS, pero su peso en TB es el 50,10% del total. El impacto de los estudios de tomografía computarizada no se ha dimensionado ni previsto adecuadamente, lo que ha impactado en la disponibilidad esperada para los estudios de un año on line. Este estudio ha permitido valorar adecuadamente el impacto de la tomografía computarizada en la disponibilidad del PACS, y cómo debe ser considerado al planificar la implementación de un PACS.

[Shunt dysfunction secondary to peritoneal catheter migration to the scrotum]. / Malfunción valvular intermitente por migración del catéter peritoneal a escroto.

INTRODUCTION: Valvular dysfunction secondary to obstruction of proximal catheter is relatively frequent at emergency room. However non-infectius obstruction of distal catheter is exceptional. CASE REPORT: A 6-year-old boy with dysfunction shunt due to migration of the abdominal catheter into the right scrotum. The patient was operated urgently for peritoneum-vaginal processus closure. DISCUSSION: Permeability of the peritoneum-vaginal processus (until 60% of boys younger than one year) causes hydrocele in patients with ventricle-peritoneal shunt. However migration of the peritoneal cateter is very infrequent specially in patients older than one year. In the case of this event with increased intracraneal pressure levels and shunt malfunction, emergency closure of the duct should be a priority.

Malfunción valvular intermitente por migración del catéter peritoneal a escroto / Shunt dysfunction secondary to peritoneal catheter migration to the scrotum

Introducción. La malfunción valvular por obstrucción del catéter proximal es un hecho relativamente frecuente en el servicio de urgencias de los grandes hospitales, pero la obstrucción distal de causa no infecciosa es excepcional. Caso clínico. Presentamos un varón de 6 años con malfunción valvular aguda, por migración del catéter distal al hemiescroto derecho. Para resolver el cuadro completamente se realizó un cierre del conducto peritoneo-vaginal de urgencia. Discusión. La permeabilidad del conducto peritoneo-vaginal (existente en hasta el 60% de los varones menores de 1 año) es la causante de los hidroceles en los pacientes portadores de una derivación ventrículo-peritoneal. Pero la migración del catéter es muy infrecuente, sobre todo en mayores de un año. Si este hecho conlleva el aumento de la presión intracraneal con disfunción valvular, el cierre de urgencia de dicho conducto debe ser prioritario.(AU)

Introduction. Valvular dysfunction secondary to obstruction of proximal catheter is relatively frequent at emergency room. However non-infectius obstruction of distal catheter is exceptional. Case report. A 6-year-old boy with dysfunction shunt due to migration of the abdominal catheter into the right scrotum. The patient was operated urgently for peritoneum-vaginal processus closure. Discussion. Permeability of the peritoneum-vaginal processus (until 60% of boys younger than one year) causes hydrocele in patients with ventricle-peritoneal shunt. However migration of the peritoneal cateter is very infrequent specially in patients older than one year. In the case of this event with increased intracraneal pressure levels and shunt malfunction, emergency closure of the duct should be a priority.(AU)

Malfunción valvular intermitente por migración del catéter peritoneal a escroto / Shunt dysfunction secondary to peritoneal catheter migration to the scrotum

Introducción. La malfunción valvular por obstrucción del catéter proximal es un hecho relativamente frecuente en el servicio de urgencias de los grandes hospitales, pero la obstrucción distal de causa no infecciosa es excepcional. Caso clínico. Presentamos un varón de 6 años con malfunción valvular aguda, por migración del catéter distal al hemiescroto derecho. Para resolver el cuadro completamente se realizó un cierre del conducto peritoneo-vaginal de urgencia. Discusión. La permeabilidad del conducto peritoneo-vaginal (existente en hasta el 60% de los varones menores de 1 año) es la causante de los hidroceles en los pacientes portadores de una derivación ventrículo-peritoneal. Pero la migración del catéter es muy infrecuente, sobre todo en mayores de un año. Si este hecho conlleva el aumento de la presión intracraneal con disfunción valvular, el cierre de urgencia de dicho conducto debe ser prioritario.

Introduction. Valvular dysfunction secondary to obstruction of proximal catheter is relatively frequent at emergency room. However non-infectius obstruction of distal catheter is exceptional. Case report. A 6-year-old boy with dysfunction shunt due to migration of the abdominal catheter into the right scrotum. The patient was operated urgently for peritoneum-vaginal processus closure. Discussion. Permeability of the peritoneum-vaginal processus (until 60% of boys younger than one year) causes hydrocele in patients with ventricle-peritoneal shunt. However migration of the peritoneal cateter is very infrequent specially in patients older than one year. In the case of this event with increased intracraneal pressure levels and shunt malfunction, emergency closure of the duct should be a priority.

Malfunción valvular intermitente por migración del catéter peritoneal a escroto. / [Shunt dysfunction secondary to peritoneal catheter migration to the scrotum].

INTRODUCTION: Valvular dysfunction secondary to obstruction of proximal catheter is relatively frequent at emergency room. However non-infectius obstruction of distal catheter is exceptional. CASE REPORT: A 6-year-old boy with dysfunction shunt due to migration of the abdominal catheter into the right scrotum. The patient was operated urgently for peritoneum-vaginal processus closure. DISCUSSION: Permeability of the peritoneum-vaginal processus (until 60

of boys younger than one year) causes hydrocele in patients with ventricle-peritoneal shunt. However migration of the peritoneal cateter is very infrequent specially in patients older than one year. In the case of this event with increased intracraneal pressure levels and shunt malfunction, emergency closure of the duct should be a priority.

Social capital at work: psychometric analysis of a short scale in Spanish among Mexican health workers.

Most studies on social capital and health are carried out with large home-based surveys, neglecting that many interactions among individuals occur in the workplace. The objective of this study was to explore the psychometric properties of a scale in Spanish used to measure social capital at work. The scale designed by Kouvonen et al was translated into Spanish and tested under classical test theory, item response theory, and confirmatory factorial analysis; 152 public health workers from different socio-cultural contexts participated in the survey. Internal consistency was high (Chronbach's alpha = 0.88). Social capital at work correlated properly with two Job Content Questionnaire dimensions. A ceiling effect was detected and item difficulty was quantified. The confirmatory factor analysis showed the expected theoretical components of social capital: bonding, bridging and trust. The scale has acceptable psychometric properties, thus it can be used in future studies.

Capital social en el trabajo: Análisis psicométrico de una escala breve en español entre trabajadores de la salud mexicanos / Social capital at work: psychometric analysis of a short scale in Spanish among Mexican health workers

La mayoría de estudios sobre capital social y salud se realizan con grandes encuestas en hogares, olvidando que muchas interacciones entre los individuos ocurren en el ambiente laboral. Este estudio tuvo como objetivo evaluar las propiedades psicométricas de una escala en español para la medición del capital social en el trabajo. La escala de Kouvonen y colaboradores fue traducida al español y evaluada mediante la teoría clásica de las pruebas, la teoría de respuesta a los ítems y análisis factorial confirmatorio. Participaron 152 trabajadores de la salud mexicanos de diferentes contextos socioculturales. La consistencia interna fue alta (alfa de Cronbach= 0.88). El capital social en el trabajo se correlacionó adecuadamente con dos dimensiones del Cuestionario de Contenido del Trabajo. Se detectó un efecto techo y se cuantificó la dificultad de los ítems. El análisis factorial confirmatorio mostró los componentes teóricamente esperados de vinculación, puente y confianza del capital social en el trabajo. La escala tuvo un aceptable comportamiento psicométrico, por lo que podrá ser utilizada en futuros estudios.

Most studies on social capital and health are carried out with large home-based surveys, neglecting that many interactions among individuals occur in the workplace. The objective of this study was to explore the psychometric properties of a scale in Spanish used to measure social capital at work. The scale designed by Kouvonen et al was translated into Spanish and tested under classical test theory, item response theory, and confirmatory factorial analysis; 152 public health workers from different socio-cultural contexts participated in the survey. Internal consistency was high (Chronbach's alpha = 0.88). Social capital at work correlated properly with two Job Content Questionnaire dimensions. A ceiling effect was detected and item difficulty was quantified. The confirmatory factor analysis showed the expected theoretical components of social capital: bonding, bridging and trust. The scale has acceptable psychometric properties, thus it can be used in future studies.

Role of electrostatics on membrane binding, aggregation and destabilization induced by NAD(P)H dehydrogenases. Implication in membrane fusion.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is considered a classical glycolytic protein that can promote the fusion of phospholipid vesicles and can also play a vital role on in vivo fusogenic events. However, it is not clear how this redox enzyme, which lack conserved structural or sequence motifs related to membrane fusion, catalyze this process. In order to detect if this ability is present in other NAD(P)H dehydrogenases with available structure, spectroscopic studies were performed to evaluate the capability of alcohol dehydrogenase (ADH), glutamic dehydrogenase (GDH) and sorbitol dehydrogenase (SDH) to bind, aggregate, destabilize and fuse vesicles. Based on finite difference Poisson-Boltzmann calculations (FDPB) the protein-membrane interactions were analyzed. A model for the protein-membrane complex in its minimum free energy of interaction was obtained for each protein and the amino acids involved in the binding processes were suggested. A previously undescribed relationship between membrane destabilization and crevices with high electropositive potential on the protein surface was proposed. The putative implication of the non-specific electrostatics on NAD(P)H dehydrogenases induced membrane fusion is discussed.

Evidence for Cu(I)-thiolate ligation and prediction of a putative copper-binding site in the Escherichia coli NADH dehydrogenase-2.

NADH dehydrogenase-2 (NDH-2) from Escherichia coli is a membrane-bound flavoprotein linked to the respiratory chain. We have previously shown that this enzyme has cupric reductase activity that is involved in hydroperoxide-induced oxidative stress. In this paper we present spectroscopic evidence that NDH-2 contains thiolate-bound Cu(I) with luminescence properties. Purified NDH-2 exhibits an emission band at 670nm with excitation wavelengths of 280 and 580nm. This emission is quenched by the specific Cu(I) chelator bathocuproine disulfonate, but not by EDTA. The luminescence intensity is sensitive to the enzyme substrates and, thus, the Cu(I)-thiolate chromophore reflects the redox and/or conformational states of the protein. There is one copper atom per polypeptide chain of the purified NDH-2, as determined by atomic absorption spectroscopy. Bioinformatics allowed us to recognize a putative copper-binding site and to predict four structural/functional domains in NDH-2: (I) the FAD-binding domain, (II) the NAD(H)-binding domain, (III) the copper-binding domain, and (IV) the domain of anchorage to the membrane containing two transmembrane helices, at the C-terminus. A NDH-2 topology model, based on the secondary structure prediction, is proposed. This is the first description of a copper-containing NADH dehydrogenase. Comparative sequence analysis allowed us to identify a branch of homologous dehydrogenases that bear a similar metal-binding motif.