Antioxidant and antimicrobial activity of two Costa Rican cultivars of ber (Ziziphus mauritiana): An underexploited crop in the American tropic.

Ber is an antioxidant-rich fruit from Asia and has recently been cultured in Central America. The antioxidant capacity and antimicrobial activity of Z. mauritiana cultured of bers from Guanacaste, Costa Rica, were evaluated. Two farm locations and two cultivars were evaluated. Total polyphenolic compounds (TPC), proanthocyanidin compounds (PAC), and ascorbic acid were spectrophotometrically quantified. Antioxidant activity has been analyzed using the DPPH method. Antimicrobial susceptibility was determined using the Kirby-Bauer disk diffusion method. Ber samples contained 11-44 mg GAE/g TPC. Green fruits and leaves had the highest concentrations. The ascorbic acid concentration in ber fruits was determined between 251 and 466 mg/100 g. Ber vitamin C content is higher than most common fruits. Proanthocyanidin compounds were determined between 1.8 and 9.9 mg 4-MCG/g, and the highest concentration was observed in the leaves. Our samples showed the antioxidant activity of 90-387 µmol TE/g, which was moderate activity. The nutritional quality of ber fruits was related to maturity conditions. The ber fruits, a crop from Asia previously adapted to live in Costa Rica, are rich in vitamin C and TPC, and the concentration of those metabolites was even higher than the concentration reported in bers grown in other countries. The TPC and PACs had an interestingly wide antimicrobial spectrum. Cultivars and farm locations have a significant effect on metabolite production.

Fluorescence dilution technique for measurement of albumin reflection coefficient in isolated glomeruli.

This study describes a high-throughput fluorescence dilution technique to measure the albumin reflection coefficient (σAlb) of isolated glomeruli. Rats were injected with FITC-dextran 250 (75 mg/kg), and the glomeruli were isolated in a 6% BSA solution. Changes in the fluorescence of the glomerulus due to water influx in response to an imposed oncotic gradient was used to determine σAlb. Adjustment of the albumin concentration of the bath from 6 to 5, 4, 3, and 2% produced a 10, 25, 35, and 50% decrease in the fluorescence of the glomeruli. Pretreatment of glomeruli with protamine sulfate (2 mg/ml) or TGF-ß1 (10 ng/ml) decreased σAlb from 1 to 0.54 and 0.48, respectively. Water and solute movement were modeled using Kedem-Katchalsky equations, and the measured responses closely fit the predicted behavior, indicating that loss of albumin by solvent drag or diffusion is negligible compared with the movement of water. We also found that σAlb was reduced by 17% in fawn hooded hypertensive rats, 33% in hypertensive Dahl salt-sensitive (SS) rats, 26% in streptozotocin-treated diabetic Dahl SS rats, and 21% in 6-mo old type II diabetic nephropathy rats relative to control Sprague-Dawley rats. The changes in glomerular permeability to albumin were correlated with the degree of proteinuria in these strains. These findings indicate that the fluorescence dilution technique can be used to measure σAlb in populations of isolated glomeruli and provides a means to assess the development of glomerular injury in hypertensive and diabetic models.

Profiling of chromosomal changes in potentially malignant and malignant oral mucosal lesions from South and South-East Asia using array-comparative genomic hybridization.

BACKGROUND/AIM: Using array-CGH, the present study aimed to explore genome-wide profiles of chromosomal aberrations in samples of oral cancer (OC), oral submucous fibrosis (OSF) and their corresponding normal oral mucosa from Indian (n=18) and OC from Sri Lankan (n=12) patients with history of BQ use, and correlate the findings to other clinicopathological parameters. A second aim was to verify the results from the array-CGH by selecting a candidate gene, S100A14, and examine its expression and genetic polymorphisms by immunohistochemistry (IHC) and restriction fragment length polymorphism (RFLP) using samples from both populations and from multi-national archival DNA and paraffin-embedded samples of OC. RESULTS: In OC and OSF samples, 80 chromosomal regions (harboring 349 genes) were found as deleted or amplified. Out of the 349 genes, 34 (including several S100 gene family members) were found to be deleted and 30 (containing NOTCH4, TP53 and ERBB2) were found as amplified in OSF and OC cases. 285 genes (including TP53, ERBB2 and BRCA1) were found either as deleted in one population or amplified in the other. Few chromosomal alterations were found to be exclusive to either OC or OSF samples alone. IHC demonstrated down-regulation and transfer of S100A14 protein expression from membrane to cytoplasmic. RFLP showed differential distribution between Asian samples compared to African and Western samples at 461 G>A SNP. CONCLUSION: The present study provides findings on chromosomal aberrations likely to be involved in pathogenesis of OC and OSF. Findings of chromosomal changes harboring genes previously found in OC examined from Western, African and Asian populations demonstrate the importance of these changes in development of OC, and the existence of common gene-specific amplifications/deletions, regardless of source of samples or attributed risk factors. We report a down-regulation of S100A14 expression to be a significant marker in association with loss of 1q21 in 70% of OC samples.

Analysis of protein expression profile of oral squamous cell carcinoma by MALDI-TOF-MS.

In this study, two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF-MS) technology was used to examine differentially expressed proteins in oral squamous cell carcinoma (OSCC) tissues from Norway (n=15) and the UK (n=45). Twenty-nine proteins were found to be significantly overexpressed in the OSCCs examined compared to the normal controls. Identified proteins included, family of annexin proteins that play important roles in signal transduction pathways and regulation of cellular growth, keratin-1, heat-shock proteins (HSP), squamous cell carcinoma antigen (SCC-Ag), cytoskeleton proteins, and proteins involved in mitochondrial and intracellular signalling pathways. The expression of four selected proteins (annexin II and V, HSP-27, and SCC-Ag) was verified using western blot analysis of 76 fresh tissue biopsy specimens in total, from Norway (n=53) and the UK (n=23). Proteomic analysis of OSCCs examined here demonstrated involvement of several proteins that might function as potential biomarkers and molecular targets for early cancer diagnostics, and may contribute to a novel approach to therapeutics and for predicting prognosis of OSCC.

Orientation dependence of the intrinsic anomalous Hall effect in hcp Cobalt.

We carry out first-principles calculations of the dependence of the intrinsic anomalous Hall conductivity of hcp Co on the spin magnetization direction. The Hall conductivity drops from 481 to 116 S/cm as the magnetization is tilted from the easy axis (c axis) to the ab plane. These values agree reasonably well with measurements on single crystals, while the angular average of 226 S/cm is in excellent agreement with the value of 205 S/cm measured in polycrystalline films. The strong intrinsic anisotropy is shown to arise from quasidegeneracies near the Fermi level.

Chromosomal aberrations in head and neck squamous cell carcinomas in Norwegian and Sudanese populations by array comparative genomic hybridization.

We used microarray-based comparative genomic hybridization to explore genome-wide profiles of chromosomal aberrations in 26 samples of head and neck cancers compared to their pair-wise normal controls. The samples were obtained from Sudanese (n=11) and Norwegian (n=15) patients. The findings were correlated with clinicopathological variables. We identified the amplification of 41 common chromosomal regions (harboring 149 candidate genes) and the deletion of 22 (28 candidate genes). Predominant chromosomal alterations that were observed included high-level amplification at 1q21 (harboring the S100A gene family) and 11q22 (including several MMP family members). Regions of copy number increase was also identified at 6p21 (p21), 7p12 (EGFR), 17p13 (p53) and 19p13.2 (p19INK4d), while regions showing deletion included among others 3p25.2 (RAF1) and 9p21 (p15, p16). We found genes from four common biological pathways (MAPK signaling, cytokine-cytokine receptor interaction, ECM-receptor interaction and Jak-STAT signaling) to be predominantly over-represented in areas of gain and loss. The current study provides valuable information on chromosomal aberrations likely to be involved in the pathogenesis of head and neck cancers. An increased copy number of the S100A and MMP gene family members, known to be involved in invasion and metastasis, may play an important role in the development of the tumors. Hierarchical clustering of the chromosomal alterations with clinicopathological parameters showed little correlation, suggesting an occurrence of gains/losses regardless of ethnic differences and clinicopathological status between the patients from the two countries. Our findings indicate the existence of common gene-specific amplifications/deletions in these tumors, regardless of the source of the samples or attributed carcinogenic risk factors.

Multiobjective analysis of a public wellfield using artificial neural networks.

As competition for increasingly scarce ground water resources grows, many decision makers may come to rely upon rigorous multiobjective techniques to help identify appropriate and defensible policies, particularly when disparate stakeholder groups are involved. In this study, decision analysis was conducted on a public water supply wellfield to balance water supply needs with well vulnerability to contamination from a nearby ground water contaminant plume. With few alternative water sources, decision makers must balance the conflicting objectives of maximizing water supply volume from noncontaminated wells while minimizing their vulnerability to contamination from the plume. Artificial neural networks (ANNs) were developed with simulation data from a numerical ground water flow model developed for the study area. The ANN-derived state transition equations were embedded into a multiobjective optimization model, from which the Pareto frontier or trade-off curve between water supply and wellfield vulnerability was identified. Relative preference values and power factors were assigned to the three stakeholders, namely the company whose waste contaminated the aquifer, the community supplied by the wells, and the water utility company that owns and operates the wells. A compromise pumping policy that effectively balances the two conflicting objectives in accordance with the preferences of the three stakeholder groups was then identified using various distance-based methods.

Descripción de desigualdades en dimensiones psicosociales y de salud mental en grupo de jóvenes estudiantes / Description of inequalities in psychosocial dimensions and mental health in group of young students

Este trabajo tiene por objetivo describir las desigualdades en aspectos psicosociales y de salud mental en jóvenes de diferente condición socioeconómica, con la finalidad de contribuir al estudio de las inequidades en nuestro país. La muestra estuvo constituida por 1.250 jóvenes de 3º medio de todos los colegios de la XII Región (públicos, subvencionados y particulares). Se realizó un análisis diferenciado por sexo para incorporar una visión de género. Se encontró una fuerte asociación entre el tipo de colegio y el nivel de estudios de los padres, al igual que con la frecuencia con que la madre trabaja fuera del hogar. Los jóvenes de colegios públicos tenían una mayor proporción de padres separados. Dentro del grupo de mujeres, las que estudiaban con colegios municipalizados o subvencionados referían con mayor frecuencia sentirse ansiosas y/o deprimidas y en una menor proporción habían tenido atenciones con psicólogo o psiquiatra. Este mismo grupo presenta una mayor cantidad de eventos vitales, una percepción de menor apoyo por parte de sus padres, así como una tendencia a una autoestima más baja y a tener una percepción de menor apoyo por parte de sus amigos(as). Entre los varones, sólo se encontraron diferencias en la frecuencia de consulta a profesionales de la salud mental y en la percepción de apoyo por parte de los amigos. Se discuten las posibles interacciones entre el género y la condición socioeconómica

Consumo de sustancias, impulsividad y factores psicosociales en estudiantes de enseñanza media / Substance abuse inpulsiveness and psychosocial factors in high school students

Este trabajo busca estudiar la relación entre consumo de sustancias (tabaco, alcohol y drogas ilícitas), impulsividad y diferentes factores psicosociales, con la finalidad de proponer "modelos explicativos" que sirvan de orientación a las acciones de prevención que se realizan en este campo. Se estudia una población de 1.250 estudiantes de 3º medio de la Región de Magallanes. Los resultados muestran que existe una asociación significativa entre impulsividad y consumo de sustancias (para cualquiera de estas). A su vez, la impulsividad se asocia com mayor sintomatología ansioso - depresiva, un mayor número de eventos estresantes, una menor autoestima y una percepción de menor apoyo social por parte de los padres. En las mujeres, a estas cuatro variables se agregan la baja afectividad positiva y la participación en grupos sociales. También se analiza la relación entre estas variables psicosociales, culminando con la proposición de "modelos explicativos" diferenciados por género. Se destaca la importancia que esto puede tener para la efectividad de las intervenciones en este campo

Consumo de tabaco entre estudiantes de enseñanza media: descripción del hábito tabáquico y de factores asociados / Tobacco consumption among high school students: description of smoking habit and associated factors

El propósito de este estudio es describir las características del consumo de tabaco en grupo de jóvenes estudiantes, así como de diferentes variables que se consideran relevantes como factores explicativos. Se trata de un estudio transversal, donde se aplica una encuesta autoadministrada, a todos los estudiantes de 3º medio de la Región de Magallanes (n=1.386). Se encontró que un 74,6 por ciento ha fumado al menos una vez en su vida. En general, los varones tienden a tener un mayor consumo de cigarrillos que las mujeres, lo que es especialmente notorio en el grupo que actualmente fuma y lo hace de manera habitual. Entre las variables que aparecen frecuentemente asociadas de manera significativa están las siguientes: el haber pensado en abandonar el colegio, la existencia de otras personas cercanas al joven que fuman (especialmente los amigos, y algo menos la madre), otras conductas de riesgo (impulsividad, consumo excesivo de alcohol y uso de drogas ilegales), algunas variables psicosociales (especialmente el número de eventos vitales y el nivel de sintomatología ansioso-depresiva), las creencias sobre el potencial daño que puede producir este hábito y la percepción del propio control sobre la conducta de consumo. Se encuentra un perfil diferencial para varones y mujeres

Consumo de tabaco entre estudiantes de enseñanza media: construcción de un modelo explicativo para el consumo / Tobacco consumption among high school students: construction of an explain model for consumption

El propósito de este trabajo es construir un modelo explicativo para la conducta de consumo de tabaco, que considere las diferencias de género y los distintos momentos en la progresión del hábito tabáquico. Todo lo anterior posibilitaría la identificación de factores que sean relevantes para acciones preventivas y terapéuticas. Es un estudio transversal, donde se aplica una encuesta autoadministrada, a todos los estudiantes de 3º medio de la Región de Magallanes (n=1386). Se investigaron variables sociodemográficas, relación con el colegio, modelos en el hábito tabáquico, dimensiones psicosociales, características del consumo y otras conductas de riesgo (consumo de alcohol y drogas ilegales). Se construyeron modelos a través de un análisis de regresión logística múltiple. Entre las conclusiones se destaca la importancia de considerar las diferencias de género y los distintos momentos en la progresión del hábito tabáquico. Al igual que abordar en forma integral al joven con conductas riesgosas, la necesidad de considerar el grupo de pares y a los padres, la eficacia de los mensajes centrados en el daño que produce el tabaco, así como la importancia de variables cognitivas y emocionales