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Biology subjects

Rosas-Vargas, H.

Publications and source records attributed to Rosas-Vargas, H..

3 recordsLinked to original sources

Association of oxidative stress, telomere length, and frailty in an elder population

BackgroundA global aging population requires focusing on the risk factors for unhealthy aging, preventive medicine, and chronic disease management. The identification of adverse health outcomes in older adults has been addressed by the characterization of frailty as a biological syndrome. On the other hand, oxidative stress and telomere length have been suggested as biomarkers of aging.\n\nObjectiveTo study the association of oxidative stress, telomere length, and frailty in an old age population.\n\nMethodsThis was a cross-sectional study based on 2015 data from 202 members from a cohort of older adults (n=202; gender F/M ratio: 133/69; mean age: 69.89 {+/-} 7.39 years). Reactive oxygen species (ROS) were measured by dichlorofluorescin diacetate, and lipid peroxidation by malondialdehyde. Telomere length was determined using qPCR with SYBR Green Master Mix.\n\nResultsStatistical analysis showed an association between telomere length and frailty but no association between oxidative stress on telomere length or frailty.\n\nConclusionsTelomere length could eventually be used as a marker to discriminate between healthy and unhealthy aging as expressed by frailty phenotype. However, oxidative stress seems as just a biological process of aging.

molecular biology

Development of a novel protein identification approach to define mitochondrial proteomic signatures in glioblastoma oncogenesis: T98G vs U87MG cell lines model.

Glioblastoma Multiforme is a cancer type with an important mitochondrial component. Here was used mitochondrial proteome Random Sampling in 2D gels from T98G (oxidative metabolism) and U87MG (glycolytic metabolism) cell lines to obtain and analyze representative spots (regardless of their intensity, size, or difference in abundance between cell lines) by Principal Component Analysis for protein identification. Identified proteins were ordered into specific Protein-Protein Interaction networks, to each cell line, showing mitochondrial processes related to metabolic change, invasion, and metastasis; and other nonmitochondrial processes such as DNA translation, chaperone response, and autophagy in gliomas. T98G and U87MG cell lines were used as glioblastoma transition model; representative proteomic signatures, with the most important biological processes in each cell line, were defined. This pipeline analysis describes the metabolic status of each line and defines clear mitochondria performance differences for distinct glioblastoma stages, introducing a new useful strategy for the understanding of glioblastoma carcinogenesis formation.\n\nBiological significanceThis study defines the mitochondria as an organelle that follows and senses the carcinogenesis process by an original proteomic approach, a random sampling in 2DE gels to obtain a representative spots sample and analyzing their relative abundance by Principal Components Analysis; to faithfully describe glioblastoma cells biology.

systems biology

Association between the brain-derived neurotrophic factor Val66Met polymorphism and overweight/obesity in Mexican pediatric population

BackgroundThe functional brain-derived neurotrophic factor (BDNF) rs6265 (G196A; Val66Met) single nucleotide polymorphism has been associated with eating disorders, BMI and obesity in distinct populations, both adult and pediatric, with contradictory results involving either Val or Met as the risk variant.\n\nAim of the studyTo determine the association between the BDNF Val66Met polymorphism and BMI in Mexican children and adolescents.\n\nMethodsBDNF Val66Met genotyping by restriction fragment length polymorphism and nutritional status characterized by their BMI-for-age z-scores (BAZ) from pediatric volunteers recruited in Mexico City (n=498) were analyzed by Fishers exact test association analysis. Standardized residuals (R) were used to determine which genotype/allele had the major influence on the significant Fishers exact test statistic. Odds ratios were analyzed to measure the magnitude and direction of the association between genotype and normal weight ([&ge;] -2 SD < +1 SD) and overweight ([&ge;] +1 SD, including obesity, Ow+Ob) status with 95% confidence intervals to estimate the precision of the effect as well as 95% credible intervals to obtain the most probable estimate.\n\nResultsComparisons between GG (Val/Val), GA (Val/Met) and AA (Met/Met) genotypes or Met homozygotes vs. Val carriers (combination of GG and GA genotypes) showed significant differences (p=0.034 and p=0.037, respectively) between normal weight and the combined overweight and obese pediatric subjects. Our data showed that children/adolescents homozygous for the A allele have increased risk of overweight compared to the Val carriers (Bayes OR= 4.2, 95% CI**[1.09-33.1]).\n\nConclusionThis is the first study showing the significant association between the BDNF rs6265 AA (Met/Met) genotype and overweight/obesity in Mexican pediatric population.\n\nO_LIMexico has one of the highest pediatric overweight and obesity prevalence\nC_LIO_LIBDNF has been associated with body weight regulation.\nC_LIO_LIThe BDNF rs6265 SNP (G196A; Val66Met) has been associated with eating disorders, BMI and obesity, with contradictory results in both adults and children.\nC_LIO_LIWe found significant associations between BDNF Val66Met AA (Met/) genotype and overweight/obesity in Mexican pediatric population\nC_LIO_LIMet homozygote children/adolescents increased four times the risk of being classified in the overweight group (Ow+Ob) relative to Val carriers\nC_LI

genetics