80 research outputs found

    Mineralización de sulfuros en las ofiolitas famatinianas y rocas asociadas, Calingasta, Precordillera de San Juan

    Get PDF
    En la Precordillera occidental de la provincia de San Juan se encuentran basaltos pertenecientes a una ofiolita de edad famatiniana. Son interpretados como formados en un ambiente extensional en una cuenca oceánica poco profunda cercana a bordes continentales cubiertos por sedimentos pelágicos y turbidíticos. Se presentan como cuerpos macizos o mantos concordantes a subconcordantes y según la composición química son basaltos tholeiíticos de tipo MORB.En la región de Calingasta, las mineralizaciones corresponden a dos tipos de depósitos: a) la mina Santa Elena, un sulfuro masivo máfico pelítico, rico en metales preciosos, pobre en Cu y con elevados tenores de Pb y Zn, cuya paragénesis primaria, masiva y diseminada, consta de pirita, calcopirita, galena, esfalerita, tetraedrita argentífera, bournonita, marcasita, melnikovita, arsenopirita, oro y molibdenita. En la potente zona de oxidación se halla una veintena de sulfatos de hierro. b) una mineralización de sulfatos de Al y Mg, asociada a los sedimentos de la Formación Alcaparrosa, en alternancia con los basaltos, fundamentalmente en lutitas, producto de la oxidación de la pirita diseminada en ellas y la reacción con sus minerales aluminosilicáticos.La región de Calingasta se considera un área de interés prospectivo por su potencial para alojar otros cuerpos de sulfuros masivos.In the western Precordillera of San Juan Province are basalts belonging to a Famatinan ophiolite age. They are interpreted as formed in an extensional environment in a shallow ocean basin near continental edges covered by pelagic and turbiditic sediments. They are presented as massive bodies or concordant to subconcordant mantles and according to the chemical composition are MORB type tholeiitic basalts. In the region of Calingasta mineralization correspond to two types: a) Santa Elena mine, a mafic pelitic massive sulphide deposit rich in precious metals, Cu-poor and high contents of Pb and Zn, whose primary paragenesis, massive and disseminated, consists of pyrite, chalcopyrite, galena, sphalerite, argentiferous tetrahedrite, bournonite, marcasite, melnikovita, arsenopyrite, gold and molybdenite. A twenty iron sulfates are in the thick oxidation zone. b) Al and Mg sulfates, associated with Alcaparrosa Formation sediments, alternating with the basalts, which are mainly in shale product of the oxidation of pyrite disseminated in them and their reaction with alumina silicates minerals. Calingasta region is considered a prospective area for its potential to host other massive sulphide bodies.Fil: Brodtkorb, Milka K. de. Universidad Nacional de Río Cuarto; ArgentinaFil: Herrmann, Carlos. Secretaria de Industria y Mineria. Servicio Geológico Minero Argentino. Instituto de Geología y Recursos Minerales; ArgentinaFil: Pezzutti, Norma. No especifica;Fil: Leal, Pablo Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: González, María Paz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Meissl, Estela. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales; Argentin

    T-Bet controls cellularity of intestinal group 3 innate lymphoid cells

    Get PDF
    Innate lymphoid cells (ILC) play a significant immunological role at mucosal surfaces such as the intestine. T-bet-expressing group 1 innate lymphoid cells (ILC1) are believed to play a substantial role in inflammatory bowel disease (IBD). However, a role of T-bet-negative ILC3 in driving colitis has also been suggested in mouse models questioning T-bet as a critical factor for IBD. We report here that T-bet deficient mice had a greater cellularity of NKp46-negative ILC3 correlating with enhanced expression of RORγt and IL-7R, but independent of signaling through STAT1 or STAT4. We observed enhanced neutrophilia in the colonic lamina propria (cLP) of these animals, however, we did not detect a greater risk of T-bet-deficient mice to develop spontaneous colitis. Furthermore, by utilizing an in vivo fate-mapping approach, we identified a population of T-bet-positive precursors in NKp46-negative ILC3s. These data suggest that T-bet controls ILC3 cellularity, but does do not drive a pathogenic role of ILC3 in mice with a conventional specific pathogen-free microbiota

    T-Bet Controls Cellularity of Intestinal Group 3 Innate Lymphoid Cells.

    Get PDF
    Innate lymphoid cells (ILC) play a significant immunological role at mucosal surfaces such as the intestine. T-bet-expressing group 1 innate lymphoid cells (ILC1) are believed to play a substantial role in inflammatory bowel disease (IBD). However, a role of T-bet-negative ILC3 in driving colitis has also been suggested in mouse models questioning T-bet as a critical factor for IBD. We report here that T-bet deficient mice had a greater cellularity of NKp46-negative ILC3 correlating with enhanced expression of RORγt and IL-7R, but independent of signaling through STAT1 or STAT4. We observed enhanced neutrophilia in the colonic lamina propria (cLP) of these animals, however, we did not detect a greater risk of T-bet-deficient mice to develop spontaneous colitis. Furthermore, by utilizing an in vivo fate-mapping approach, we identified a population of T-bet-positive precursors in NKp46-negative ILC3s. These data suggest that T-bet controls ILC3 cellularity, but does do not drive a pathogenic role of ILC3 in mice with a conventional specific pathogen-free microbiota

    Congenital Diarrhea and Cholestatic Liver Disease: Phenotypic Spectrum Associated with MYO5B Mutations

    Get PDF
    Myosin Vb (MYO5B) is a motor protein that facilitates protein trafficking and recycling in polarized cells by RAB11- and RAB8-dependent mechanisms. Biallelic MYO5B mutations are identified in the majority of patients with microvillus inclusion disease (MVID). MVID is an intractable diarrhea of infantile onset with characteristic histopathologic findings that requires life-long parenteral nutrition or intestinal transplantation. A large number of such patients eventually develop cholestatic liver disease. Bi-allelic MYO5B mutations are also identified in a subset of patients with predominant early-onset cholestatic liver disease. We present here the compilation of 114 patients with disease-causing MYO5B genotypes, including 44 novel patients as well as 35 novel MYO5B mutations, and an analysis of MYO5B mutations with regard to functional consequences. Our data support the concept that (1) a complete lack of MYO5B protein or early MYO5B truncation causes predominant intestinal disease (MYO5B-MVID), (2) the expression of full-length mutant MYO5B proteins with residual function causes predominant cholestatic liver disease (MYO5B-PFIC), and (3) the expression of mutant MYO5B proteins without residual function causes both intestinal and hepatic disease (MYO5B-MIXED). Genotype-phenotype data are deposited in the existing open MYO5B database in order to improve disease diagnosis, prognosis, and genetic counseling.This research was funded by Jubiläumsfonds der Österreichischen Nationalbank, grant no.16678 (to A.R.J.), grant no. 18019 (to G.-F.V.) and Tiroler Wissenschaftsfonds, grant No. 0404/2386 (toG.-F.V.).info:eu-repo/semantics/publishedVersio

    Adaptation of pineal expressed teleost exo-rod opsin to non-image forming photoreception through enhanced Meta II decay

    Get PDF
    Photoreception by vertebrates enables both image-forming vision and non-image-forming responses such as circadian photoentrainment. Over the recent years, distinct non-rod non-cone photopigments have been found to support circadian photoreception in diverse species. By allowing specialization to this sensory task a selective advantage is implied, but the nature of that specialization remains elusive. We have used the presence of distinct rod opsin genes specialized to either image-forming (retinal rod opsin) or non-image-forming (pineal exo-rod opsin) photoreception in ray-finned fish (Actinopterygii) to gain a unique insight into this problem. A comparison of biochemical features for these paralogous opsins in two model teleosts, Fugu pufferfish (Takifugu rubripes) and zebrafish (Danio rerio), reveals striking differences. While spectral sensitivity is largely unaltered by specialization to the pineal environment, in other aspects exo-rod opsins exhibit a behavior that is quite distinct from the cardinal features of the rod opsin family. While they display a similar thermal stability, they show a greater than tenfold reduction in the lifetime of the signaling active Meta II photoproduct. We show that these features reflect structural changes in retinal association domains of helices 3 and 5 but, interestingly, not at either of the two residues known to define these characteristics in cone opsins. Our findings suggest that the requirements of non-image-forming photoreception have lead exo-rod opsin to adopt a characteristic that seemingly favors efficient bleach recovery but not at the expense of absolute sensitivity

    Identification of regulatory variants associated with genetic susceptibility to meningococcal disease

    Get PDF
    Non-coding genetic variants play an important role in driving susceptibility to complex diseases but their characterization remains challenging. Here, we employed a novel approach to interrogate the genetic risk of such polymorphisms in a more systematic way by targeting specific regulatory regions relevant for the phenotype studied. We applied this method to meningococcal disease susceptibility, using the DNA binding pattern of RELA - a NF-kB subunit, master regulator of the response to infection - under bacterial stimuli in nasopharyngeal epithelial cells. We designed a custom panel to cover these RELA binding sites and used it for targeted sequencing in cases and controls. Variant calling and association analysis were performed followed by validation of candidate polymorphisms by genotyping in three independent cohorts. We identified two new polymorphisms, rs4823231 and rs11913168, showing signs of association with meningococcal disease susceptibility. In addition, using our genomic data as well as publicly available resources, we found evidences for these SNPs to have potential regulatory effects on ATXN10 and LIF genes respectively. The variants and related candidate genes are relevant for infectious diseases and may have important contribution for meningococcal disease pathology. Finally, we described a novel genetic association approach that could be applied to other phenotypes

    Identification of regulatory variants associated with genetic susceptibility to meningococcal disease.

    Get PDF
    Non-coding genetic variants play an important role in driving susceptibility to complex diseases but their characterization remains challenging. Here, we employed a novel approach to interrogate the genetic risk of such polymorphisms in a more systematic way by targeting specific regulatory regions relevant for the phenotype studied. We applied this method to meningococcal disease susceptibility, using the DNA binding pattern of RELA - a NF-kB subunit, master regulator of the response to infection - under bacterial stimuli in nasopharyngeal epithelial cells. We designed a custom panel to cover these RELA binding sites and used it for targeted sequencing in cases and controls. Variant calling and association analysis were performed followed by validation of candidate polymorphisms by genotyping in three independent cohorts. We identified two new polymorphisms, rs4823231 and rs11913168, showing signs of association with meningococcal disease susceptibility. In addition, using our genomic data as well as publicly available resources, we found evidences for these SNPs to have potential regulatory effects on ATXN10 and LIF genes respectively. The variants and related candidate genes are relevant for infectious diseases and may have important contribution for meningococcal disease pathology. Finally, we described a novel genetic association approach that could be applied to other phenotypes
    corecore