858 research outputs found

    New late Tremadocian (Early Ordovician) conodont and graptolite records from the southern South American Gondwana margin (Eastern Cordillera, Argentina)

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    New late Tremadocian (Early Ordovician) conodont and graptolite faunas from the eastern and central belts of the Eastern Cordillera (Jujuy Province, northwestern Argentina) are reported. The conodont fauna includes the guide species Paltodus deltifer pristinus, Paltodus deltifer deltifer, and Acodus deltatus (sensu lato), in association with other taxa, and the graptolites Aorograptus victoriae, Ancoragraptus cf. bulmani, and Adelograptus cf. altus. Overlapping ranges of the recorded species allow for a partial correlation between the Acodus deltatus- Paroistodus proteus and Aorograptus victoriae zones, and the Notopeltis orthometopa trilobite Zone. The conodont fauna includes a mixture of forms typical of the Baltoscandian and Laurentian provinces, respectively. The Early Ordovician basin of northwestern Argentina may correspond to the Shallow-Sea Realm and Cold Domain and probably records the development of a differentiated conodont province in the southern South American margin of Gondwana

    Tremadocian Graptolite-Conodont Biostratigraphy of the South American Gondwana margin (Eastern Cordillera, NW Argentina)

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    The Tremadocian graptolite and conodont faunas of the Gondwana Margin recorded at the Eastern Cordillera (EC) of Salta and Jujuy provinces (northwestern Argentina) are studied. The previous data and the new provided information indicate that a “no nominated interval” and several graptolite zones (Anisograptus matanensis, Rhabdinopora flabelliformis anglica, Bryograptus, Kiaerograptus, Kiaerograptus supremus, Araneograptus murrayi, and Hunnegraptus copiosus zones), as well as several conodont zones (Iapetognathus, Cordylodus angulatus, Paltodus deltifer, and Acodus deltatus - Paroistodus proteus zones) occur in the Ordovician successions studied. New or reappraised data from sections such as Angosto del Moreno, Angosto de Lampazar, Parcha-Incamayo-Incahuasi area, and Cajas range (EC western margin), and Alfarcito area and Mojotoro range (EC eastern margin), provide new information on the composition of the fossil faunas. A composite graptoliteconodont biostratigraphic framework, including records of key trilobites as external control group, is proposed for the Tremadocian of the South American margin of Gondwana. Both fossil groups are generally recorded from outer platform to ocean basin environments, showing significant similarities with the Baltoscandian faunas. Nevertheless, particular shallow-water facies include either specific forms or species associations that are common to the epeiric shallow-water seas of Laurentia. This fact demonstrates an important interplay between faunas of different regions of the Iapetus Ocean during the Tremadocian

    High resolution conodont-graptolite biostratigraphy in the Middle-Upper Ordovician of the Sierra de La Invernada Formation (Central Precordillera, Argentina)

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    Outcrops on the western slope of the La Invernada Range, San Juan Precordillera (W Argentina), were surveyed for lithofacial analysis and graptolite-conodont high resolution biostratigraphy. The study profile for the upper Sierra de La Invernada Formation is approximately 500 m thick and is located in the northern part of the La Invernada Range. Successive shallowing-deepening sedimentary cycles crop out throughout the upper part of the formation. The dominantly lower turbiditic sandy deposits alternate with shaly pelagic sedimentation, and occasional coarser intervals that record gravitational flows. Hummocky structures occur in the uppermost part of the formation, indicating sedimentation under storm weather conditions. Rich graptolite faunas representing six upper Middle to lower Upper Ordovician biozones have been recorded from this section: Pterograptus elegans (tentative assignment), Hustedograptus teretiusculus, Nemagraptus gracilis, Climacograptus bicornis, Diplacanthograptus caudatus, and Climacograptus tubuliferus biozones. This graptolite biostratigraphy is complemented by the conodont records from successive productive levels, which yielded conodonts that represent the Pygodus serra, P. anserinus, Amorphognathus tvaerensis, and A. superbus biozones. The recorded conodont-graptolite assemblages allow for a correlation with the upper Darriwilian, Sandbian and lower Katian global stages, and provide preliminary biofacies records for the upper Sierra de La Invernada Formation

    New late Tremadocian (Early Ordovician) conodont and graptolite records from the southern South American Gondwana margin (Eastern Cordillera, Argentina)

    Get PDF
    New late Tremadocian (Early Ordovician) conodont and graptolite faunas from the eastern and central belts of the Eastern Cordillera (Jujuy Province, northwestern Argentina) are reported. The conodont fauna includes the guide species Paltodus deltifer pristinus, Paltodus deltifer deltifer, and Acodus deltatus (sensu lato), in association with other taxa, and the graptolites Aorograptus victoriae, Ancoragraptus cf. bulmani, and Adelograptus cf. altus. Overlapping ranges of the recorded species allow for a partial correlation between the Acodus deltatus-Paroistodus proteus and Aorograptus victoriae zones, and the Notopeltis orthometopa trilobite Zone. The conodont fauna includes a mixture of forms typical of the Baltoscandian and Laurentian provinces, respectively. The Early Ordovician basin of northwestern Argentina may correspond to the Shallow-Sea Realm and Cold Domain and probably records the development of a differentiated conodont province in the southern South American margin of Gondwana

    Adipose-derived stem/stromal cells in kidney transplantation: Status quo and future perspectives

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    Kidney transplantation (KT) is the gold standard treatment of end-stage renal disease. Despite progressive advances in organ preservation, surgical technique, intensive care, and immunosuppression, long-term allograft survival has not significantly improved. Among the many peri-operative complications that can jeopardize transplant outcomes, ischemia-reperfusion injury (IRI) deserves special consideration as it is associated with delayed graft function, acute rejection, and premature transplant loss. Over the years, several strategies have been proposed to mitigate the impact of IRI and favor tolerance, with rather disappointing results. There is mounting evidence that adipose stem/stromal cells (ASCs) possess specific characteristics that could help prevent, reduce, or reverse IRI. Immunomodulating and tolerogenic properties have also been suggested, thus leading to the development of ASC-based prophylactic and therapeutic strategies in pre-clinical and clinical models of renal IRI and allograft rejection. ASCs are copious, easy to harvest, and readily expandable in culture. Furthermore, ASCs can secrete extracellular vesicles (EV) which may act as powerful mediators of tissue repair and tolerance. In the present review, we discuss the current knowledge on the mechanisms of action and therapeutic opportunities offered by ASCs and ASC-derived EVs in the KT setting. Most relevant pre-clinical and clinical studies as well as actual limitations and future perspective are highlighted

    High resolution conodont-graptolite biostratigraphy in the Middle-Upper Ordovician of the Sierra de La Invernada Formation (Central Precordillera, Argentina)

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    Outcrops on the western slope of the La Invernada Range, San Juan Precordillera (W Argentina), were surveyed for lithofacial analysis and graptolite-conodont high resolution biostratigraphy. The study profile for the upper Sierra de La Invernada Formation is approximately 500 m thick and is located in the northern part of the La Invernada Range. Successive shallowing-deepening sedimentary cycles crop out throughout the upper part of the formation. The dominantly lower turbiditic sandy deposits alternate with shaly pelagic sedimentation, and occasional coarser intervals that record gravitational flows. Hummocky structures occur in the uppermost part of the formation, indicating sedimentation under storm weather conditions. Rich graptolite faunas representing six upper Middle to lower Upper Ordovician biozones have been recorded from this section: Pterograptus elegans (tentative assignment), Hustedograptus teretiusculus, Nemagraptus gracilis, Climacograptus bicornis, Diplacanthograptus caudatus, and Climacograptus tubuliferus biozones. This graptolite biostratigraphy is complemented by the conodont records from successive productive levels, which yielded conodonts that represent the Pygodus serra, P. anserinus, Amorphognathus tvaerensis, and A. superbus biozones. The recorded conodont-graptolite assemblages allow for a correlation with the upper Darriwilian, Sandbian and lower Katian global stages, and provide preliminary biofacies records for the upper Sierra de La Invernada Formation

    Allelic Variants of HLA-C Upstream Region, PSORS1C3, MICA, TNFA and Genes Involved in Epidermal Homeostasis and Barrier Function Influence the Clinical Response to Anti-IL-12/IL-23 Treatment of Patients with Psoriasis

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    Several biologic therapies have been developed to treat moderate-to-severe psoriasis, with patients exhibiting different clinical benefits, possibly due to the heterogeneity of pathogenic processes underlying their conditions. Ustekinumab targets the IL-12/IL-23-p40 subunit and inhibits type-1 and type-17 T-cell responses. Although ustekinumab is effective as both short- and long-term treatment, therapeutic response varies considerably among patients. Ustekinumab biosimilars will be commercialized in the very next future, likely broadening the use of this drug in the treatment of psoriasis patients. Our pharmacogenomic study evaluated the influence of 417 single-nucleotide polymorphisms (SNPs) in psoriasis-risk alleles on the clinical response to ustekinumab in a cohort of 152 patients affected by moderate-to-severe plaque-type psoriasis. Differences in SNP pattern characterizing HLA-Cw6(+) or HLA-Cw6(-) patients, showing high or low responses to ustekinumab, were also analysed. We identified twelve SNPs in HLA-C upstream region (rs12189871, rs4406273, rs9348862 and rs9368670), PSORS1C3 (rs1265181), MICA (rs2523497), LCE3A-B intergenic region (rs12030223, rs6701730), CDSN (rs1042127, rs4713436), CCHCR1 (rs2073719) and in TNFA (rs1800610) genes associated with excellent response to ustekinumab. We also found that HLA-Cw6(+) and HLA-Cw6(-) patients carried out distinct patterns of SNPs associated with different clinical responses. The assessment of HLA-C alleles, together with other genetic variants, could be helpful for defining patients who better benefit from anti-IL-12/IL-23 therapy
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