El polimorfismo de un solo nucleótido rs1800795 en el gen IL6 no está asociado con el glaucoma primario de ángulo abierto en la población mexicana / The rs1800795 single nucleotide polymorphism in the IL6 gene is not associated with primary open angle glaucoma in Mexican population

Objetivo La interleucina 6 (IL-6) es una citoquina proinflamatoria con efectos pleiotrópicos que se ha relacionado con el glaucoma primario de ángulo abierto (GPAA) debido a su efecto particular de protección de las células ganglionares de la retina (CGR) contra la apoptosis. Se han asociado diferentes polimorfismos de un solo nucleótido (PSN) con el GPAA. El objetivo de este estudio fue determinar si existe una asociación entre el PSN de IL-6 rs1800795 (−174 G>C) y un mayor riesgo de padecer GPAA en la población mexicana occidental. Métodos Se incluyeron 165 pacientes mestizos mexicanos no emparentados con GPAA y 108 sujetos de control. Se extrajo el ADN genómico de los leucocitos y se purificó, seguido de la genotipificación y la amplificación por reacción en cadena de la polimerasa (PCR) con sondas TaqMan® Biosystem®. Se evaluó la diversidad alélica y genotípica entre los casos y los sujetos de control. Resultados No hubo asociación estadísticamente significativa entre las frecuencias alélicas y genotípicas, ni con modelos de asociación genética dominante ni recesiva (p>0,05). Conclusiones Aunque existe un papel de la IL6 en la fisiopatología del GPAA, nuestros resultados descartan la asociación entre la IL-6 y el PSN rs1800795 mostrando no ser un índice de mayor riesgo de GPAA en la población mexicana (AU)

Purpose Interleukin-6 (IL-6) is a proinflammatory cytokine with pleiotropic effects which has been related to primary open angle glaucoma (POAG) due to its particular effect of protecting the retinal ganglion cells (RGc) from the apoptosis. Different single nucleotide polymorphisms (SNP) have been associated with POAG. The aim of this study was to determine whether an association between IL-6 rs1800795 (−174 G>C) SNP and a higher risk for POAG is present in western Mexican population. Methods One hundred and sixty-five unrelated Mexican mestizo patients with POAG and 108 control subjects were included. Genomic DNA was extracted from leukocytes and purified, followed by genotyping and amplification by polymerase chain reaction (PCR) with Taqman Biosystem probes. Allelic and genotypic diversity was evaluated between cases and control subjects. Results There was no statistically significant association between allele and genotype frequencies, neither with dominant nor recessive genetic association models (P>.05). Conclusion Even though there is a role of IL6 in the pathophysiology of POAG, our results ruled out the association between IL-6 and the rs1800795 SNP showing not to be an index of higher risk for POAG in Mexican population (AU)

The rs1800795 single nucleotide polymorphism in the IL6 gene is not associated with primary open angle glaucoma in Mexican population.

PURPOSE: Interleukin-6 (IL-6) is a proinflammatory cytokine with pleiotropic effects which has been related to primary open angle glaucoma (POAG) due to its particular effect of protecting the retinal ganglion cells (RGc) from the apoptosis. Different single nucleotide polymorphisms (SNP) have been associated with POAG. The aim of this study was to determine whether an association between IL-6 rs1800795 (-174 G>C) SNP and a higher risk for POAG is present in western Mexican population. METHODS: One hundred and sixty-five unrelated Mexican mestizo patients with POAG and 108 control subjects were included. Genomic DNA was extracted from leukocytes and purified, followed by genotyping and amplification by polymerase chain reaction (PCR) with Taqman Biosystem probes. Allelic and genotypic diversity was evaluated between cases and control subjects. RESULTS: There was no statistically significant association between allele and genotype frequencies, neither with dominant nor recessive genetic association models (p > 0.05). CONCLUSION: Even though there is a role of IL6 in the pathophysiology of POAG, our results ruled out the association between IL-6 and the rs1800795 SNP showing not to be an index of higher risk for POAG in Mexican population.

Phosphorus-rich stars with unusual abundances are challenging theoretical predictions.

Almost all chemical elements have been made by nucleosynthetic reactions in various kind of stars and have been accumulated along our cosmic history. Among those elements, the origin of phosphorus is of extreme interest because it is known to be essential for life such as we know on Earth. However, current models of (Galactic) chemical evolution under-predict the phosphorus we observe in our Solar System. Here we report the discovery of 15 phosphorus-rich stars with unusual overabundances of O, Mg, Si, Al, and Ce. Phosphorus-rich stars likely inherit their peculiar chemistry from another nearby stellar source but their intriguing chemical abundance pattern challenge the present stellar nucleosynthesis theoretical predictions. Specific effects such as rotation or advanced nucleosynthesis in convective-reactive regions in massive stars represent the most promising alternatives to explain the existence of phosphorus-rich stars. The phosphorus-rich stars progenitors may significantly contribute to the phosphorus present on Earth today.

Rubidium-rich asymptotic giant branch stars.

A long-debated issue concerning the nucleosynthesis of neutron-rich elements in asymptotic giant branch (AGB) stars is the identification of the neutron source. We report intermediate-mass (4 to 8 solar masses) AGB stars in our Galaxy that are rubidium-rich as a result of overproduction of the long-lived radioactive isotope (87)Rb, as predicted theoretically 40 years ago. This finding represents direct observational evidence that the (22)Ne(alpha,n)(25)Mg reaction must be the dominant neutron source in these stars. These stars challenge our understanding of the late stages of the evolution of intermediate-mass stars and would have promoted a highly variable Rb/Sr environment in the early solar nebula.