Single nucleotide polymorphism (SNP) analysis used for the phylogeny of the Mycobacterium tuberculosis complex based on a pyrosequencing assay

Background Different polymorphisms have been described as markers to classify the lineages of the Mycobacterium tuberculosis complex. The analysis of nine single nucleotide polymorphisms (SNPs) was used to describe seven SNPs cluster groups (SCGs). We attempted to classify those strains that could not been categorized into lineages by the genotyping methods used in the routine testing. Results The M. tuberculosis complex isolates collected in 2010 in our region were analysed. A new method based on multiplex-PCRs and pyrosequencing to analyse these SNPs was designed. For the pyrosequencing assay nine SNPs that defined the seven SCGs were selected from the literature: 1977, 74092, 105139, 232574, 311613, 913274, 2460626, 3352929 and gyrA95. In addition, SNPs in katG463, mgtC182, Ag85C103 and RDRio deletion were detected

Global study of is6110 in a successful mycobacterium tuberculosis strain: Clues for deciphering its behavior and for its rapid detection

The Mycobacterium tuberculosis insertion sequence IS6110, besides being a very useful tool in molecular epidemiology, seems to have an impact on the biology of bacilli. In the present work, we mapped the 12 points of insertion of IS6110 in the genome of a successful strain named M. tuberculosis Zaragoza (which has been referred to as the MTZ strain). This strain, belonging to principal genetic group 3, caused a large unsuspected tuberculosis outbreak involving 85 patients in Zaragoza, Spain, in 2001 to 2004. The mapping of the points of insertion of IS6110 in the genome of the Zaragoza strain offers clues for a better understanding of the adaptability and virulence of M. tuberculosis. Surprisingly, the presence of one copy of IS6110 was found in Rv2286c, as was recently described for a successful Beijing sublineage. As a result of this analysis, a rapid method for detecting this particular M. tuberculosis strain has been designed

Resorption controls bone anabolism driven by PTH receptor signaling in osteocytes

The contribution of remodeling-based bone formation coupled to osteoclast activity versus modeling-based bone formation that occurs independently of resorption, to the anabolic effect of PTH remains unclear. We addressed this question using transgenic mice with activated PTH receptor signaling in osteocytes that exhibit increased bone mass and remodeling, recognized skeletal effects of PTH elevation. Direct inhibition of bone formation was accomplished genetically by overexpressing the Wnt antagonist Sost/sclerostin; and resorption-dependent bone formation was inhibited pharmacologically with the bisphosphonate alendronate. We found that bone formation induced by osteocytic PTH receptor signaling on the periosteal surface depends on Wnt signaling but not on resorption. In contrast, bone formation on the endocortical surface results from a combination of Wnt-driven increased osteoblast number and resorption-dependent osteoblast activity. Moreover, elevated osteoclasts and intracortical/calvarial porosity is exacerbated by overexpressing Sost and reversed by blocking resorption. Furthermore, increased cancellous bone is abolished by Wnt inhibition but further increased by blocking resorption. Thus, resorption induced by PTH receptor signaling in osteocytes is critical for full anabolism in cortical bone, but tempers bone gain in cancellous bone. Dissecting underlying mechanisms of PTH receptor signaling would allow targeting actions in different bone compartments, enhancing the therapeutic potential of the pathway

EFECTO DEL GENOTIPO ANIMAL SOBRE EL RENDIMIENTO DE LA RES Y CALIDAD DE LA CARNE DE NOVILLOS ALIMENTADOS SOBRE PASTURA Y SUPLEMENTADOS EN EL PERIODO INVERNAL

El estudio fue realizado con el objetivo de determinar el rendimiento de la res y caracterizar la calidad de carne de cuatro genotipos de bovino de carne. Fueron extraídos al azar cuatro cabezas de un total de 30 animales terminados por tratamiento, sometidos a similares condiciones de manejo, sanidad y alimentación, con edad promedio de 24 meses. Los tratamientos fueron: Criollo (Cr, Bos taurus adaptado), Indico (1, Bos indicus), Trihíbrido (Tr, Bos taurus adaptado x Bos indicus x Bos taurus continental) e Híbrido (H, Bos taurus ingles x Bos indicus). El Diseño experimental fue el de bloques completos al azar, los resultados obtenidos fueron sometidos a ANAVA, las diferencias fueron analizadas por el test de Tukey al 5%. Los resultados evidencian pesos superiores de los H y Tr (sin ayuno) con respecto al Cr, mientras con ayuno solamente el H fue estadísticamente superior al Cr. Los tratamientos H, Tre I fueron estadísticamente superiores en el rendimiento en peso de la res al Cr. Los rendimientos como porcentaje del peso vivo sin y con ayuno promediaron 52.3 y 56.3 %, resp. El desbaste promedio fué de 7 %. Los tratamientos H y Tr fueron superiores al Cr en relación al cuarto pistola corto y paleta+costillar, los mismos no arrojaron diferencia como porcentaje del peso vivo sin y con ayuno. El residuo blando y el residuo duro representan el 17.1 y e113.5 % del peso vivo sin ayuno. En cuanto a la calidad de carne los parámetros espesor de grasa y color de carne presentaron diferencias estadísticas, siendo el Cr superior a los demás tratamientos (6 mm y grado 5, resp.), no se encontró diferencias en los otros parámetros. El marmoreado obtenido fue pobre, aunque el color de carne y de grasa se cualificó como muy buena (Según Standard Japonés). Los pesos de cortes de lomito (Psoas mayor) y peceto (Semitendinosus) están en relación directa a los pesos vivos de los animales de cada tratamiento (H>Tr>I>Cr), encontrándose diferencia estadística solamente en el peceto entre H y Cr.

Exploring genetic factors involved in huntington disease age of onset. E2F2 as a new potential modifier gene

Age of onset (AO) of Huntington disease (HD) is mainly determined by the length of the CAG repeat expansion (CAGexp) in exon 1 of the HTT gene. Additional genetic variation has been suggested to contribute to AO, although the mechanism by which it could affect AO is presently unknown. The aim of this study is to explore the contribution of candidate genetic factors to HD AO in order to gain insight into the pathogenic mechanisms underlying this disorder. For that purpose, two AO definitions were used: the earliest age with unequivocal signs of HD (earliest AO or eAO), and the first motor symptoms age (motor AO or mAO). Multiple linear regression analyses were performed between genetic variation within 20 candidate genes and eAO or mAO, using DNA and clinical information of 253 HD patients from REGISTRY project. Gene expression analyses were carried out by RT-qPCR with an independent sample of 35 HD patients from Basque Country Hospitals. We found suggestive association signals between HD eAO and/or mAO and genetic variation within the E2F2, ATF7IP, GRIN2A, GRIN2B, LINC01559, HIP1 and GRIK2 genes. Among them, the most significant was the association between eAO and rs2742976, mapping to the promoter region of E2F2 transcription factor. Furthermore, rs2742976 T allele patient carriers exhibited significantly lower lymphocyte E2F2 gene expression, suggesting a possible implication of E2F2-dependent transcriptional activity in HD pathogenesis. Thus, E2F2 emerges as a new potential HD AO modifier factor

Detection of key transient Cu intermediates in SSZ-13 during NH3-SCR deNOx by modulation excitation IR spectroscopy

The small pore zeolite Cu-SSZ-13 is an efficient material for the standard selective catalytic reduction of nitrogen oxides (NOx) by ammonia (NH3). In this work, Cu-SSZ-13 has been studied at 250 °C under high conversion using a modulation excitation approach and analysed with phase sensitive detection (PSD). While the complementary X-ray absorption near edge structure (XANES) spectroscopy measurements showed that the experiments were performed under cyclic Cu+/Cu2+ redox, Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) experiments provide spectroscopic evidence for previously postulated intermediates Cu–N([double bond, length as m-dash]O)–NH2 and Cu–NO3 in the NH3-SCR deNOx mechanism and for the role of [Cu2+(OH−)]+. These results therefore help in building towards a more comprehensive understanding of the reaction mechanism which to date has only been postulated in silico

Contenido de calcio y fosforo de especies nativas sometidas a tres frecuencias de corte a lo largo del año

El objetivo del trabajo fue Evaluar el contenido de Calcio y Fósforo de un pastizal nativo, en función a la frecuencia de utilización de la misma a lo largo de un año.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI