92 research outputs found

    An unusual new archosauriform from the Middle-Late Triassic of southern Brazil and the monophyly of Doswelliidae

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    Until now the Doswelliidae was considered a monospecific family including Doswellia kaltenbachi from the Late Triassic of North America. The phylogenetic position of this taxon remained enigmatic until recently, when a sister-group relationship with the Proterochampsidae was suggested. In the present contribution we describe the new doswelliid species Archeopelta arborensis gen. et sp. nov. from the Middle-Late Triassic of Brazil. A cladistic analysis recovered Archeopelta, Doswellia, and Tarjadia within a monophyletic group of basal archosauriforms, the Doswelliidae. The monophyly of this family is supported by the presence of osteoderm ornamentation that is coarse, incised, and composed of regular pits and the presence of an unornamented anterior articular lamina. Archeopelta is more closely related to Doswellia than to other archosauriforms by the presence of basipterygoid processes anterolaterally orientated, dorsal centra with a convex surface, width of the neural arch plus ribs of the first primordial sacral that are three times the length of the neural arch, and iliac blade laterally deflected, with strongly convex dorsal margin, and a length less than three times its height. The phylogenetic analysis indicates that Doswellidae is the closest large monophyletic entity to Archosauria, which achieved a wide palaeolatitudinal distribution during the late Middle and Late Triassic time span.Fil: Desojo, Julia Brenda. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Ezcurra, Martin Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Schultz, Cesar. Universidade Federal do Rio Grande do Sul; Brasi

    The skull anatomy and cranial endocast of the pseudosuchid archosaur Prestosuchus chiniquensis from the Triassic of Brazil

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    Prestosuchus chiniquensis is the most famous “rauisuchian” described by Friedrich von Huene, eight decades ago, and several specimens have been assigned to this taxon since then. In the present contribution, we provide the first detailed description of a complete and very well preserved skull (including the braincase) assigned to Prestosuchus chiniquensis from the Dinodontosaurus Assemblage Zone of the Santa Maria Supersequence of southern Brazil. The detailed description of the skull of Prestosuchus chiniquensis, besides increasing the knowledge about this taxon, may help elucidate the taxonomic relationships of pseudosuchians even further, since most of the characters used in phylogenetic analyzes are cranial. The presence of the subnarial fenestra, a controvertial extra opening on the skull of “rauisuchians”, is thoroughly discussed considering the evidence provided by this new specimen. We consider that the small slit-opening between the premaxilla and the maxilla in Prestosuchus chiniquensis, can not safely be considered a true fenestra, but indicates more likely the existence of some degree of cranial kinesis between these elements which can result in different relative positions of the bones after definitive burial and fossilization, so that the size and shape of this opening is taphonomically controlled. Complementarily, the digital reconstruction of its cranial endocast was developed both from the observation of the preserved braincase and from CT scan images, which resulted in obtaining the first endocast known for a “rauisuchian”. The endocast of Prestosuchus chiniquensis exhibited some remarkable convergences with that of theropod dinosaurs, which could be a reflection of the similar niches they occupied, since “rauisuchians” were the top predators at the end of the Late Triassic, before the extinction of all non-crocodylomorph pseudosuchians

    Intraspecific variation in the axial skeleton of Aetosauroides scagliai (Archosauria: Aetosauria) and its implications for the aetosaur diversity of the Late Triassic of Brazil

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    Aetosauria represents a remarkable clade of armored pseudosuchians in which some of its oldest members are recovered from late Carnian units of Brazil. Three species are known: The mid-sized aetosaur Aetosauroides scagliai, which also occurs in Argentina, and two small-sized species, Aetobarbakinoides brasiliensis and Polesinesuchus aurelioi. We provide a detailed description and comparative analysis of the axial skeleton of Aetosauroides, identifying some diagnostic features as variable. These include the deep pocket pit lateral to the base of the neural spine, the presence of the infradiapophyseal laminae and the lateral fossa ventral to the neurocentral suture. These features are not found in smaller and immature Aetosauroides specimens, resembling the condition found in Polesinesuchus, which is based solely on a juvenile individual, as revealed by osteoderm microstructure analysis. As Polesinesuchus cannot be anatomically differentiated from other small individuals of Aetosauroides, we propose it as a junior synonym of Aetosauroides scagliai. Our results shrink the number of putative ‘dwarf’ aetosaurs, indicating that morphological variation related to ontogeny affects aetosaur taxonomy and phylogeny.Fil: Paes Neto, Voltaire. Universidade Federal do Rio Grande do Sul; BrasilFil: Desojo, Julia Brenda. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Biacchi Brust, Ana Carolina. Universidade Federal do Rio Grande do Sul; BrasilFil: Schultz, Cesar. Universidade Federal do Rio Grande do Sul; BrasilFil: Da Rosa, Atila Augusto Stock. Universidade Federal de Santa Maria; BrasilFil: Soares, Marina. Universidade Federal do Rio de Janeiro; Brasi

    Mucoactive agents for acute respiratory failure in the critically ill: a systematic review and meta-analysis

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    Purpose Acute respiratory failure (ARF) is a common cause of admission to intensive care units (ICUs). Mucoactive agents are medications that promote mucus clearance and are frequently administered in patients with ARF, despite a lack of evidence to underpin clinical decision making. The aim of this systematic review was to determine if the use of mucoactive agents in patients with ARF improves clinical outcomes. Methods We searched electronic and grey literature (January 2020). Two reviewers independently screened, selected, extracted data and quality assessed studies. We included trials of adults receiving ventilatory support for ARF and involving at least one mucoactive agent compared with placebo or standard care. Outcomes included duration of mechanical ventilation. Meta-analysis was undertaken using random-effects modelling and certainty of the evidence was assessed using Grades of Recommendation, Assessment, Development and Evaluation. Results Thirteen randomised controlled trials were included (1712 patients), investigating four different mucoactive agents. Mucoactive agents showed no effect on duration of mechanical ventilation (seven trials, mean difference (MD)-1.34, 95% CI-2.97 to 0.29, I 2 =82%, very low certainty) or mortality, hospital stay and ventilator-free days. There was an effect on reducing ICU length of stay in the mucoactive agent groups (10 trials, MD-3.22, 95% CI-5.49 to-0.96, I 2 =89%, very low certainty). Conclusion Our findings do not support the use of mucoactive agents in critically ill patients with ARF. The existing evidence is of low quality. High-quality randomised controlled trials are needed to determine the role of specific mucoactive agents in critically ill patients with ARF. PROSPERO registration number CRD42018095408

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

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    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

    Integrated Genomic Analysis of the Ubiquitin Pathway across Cancer Types

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    Protein ubiquitination is a dynamic and reversibleprocess of adding single ubiquitin molecules orvarious ubiquitin chains to target proteins. Here,using multidimensional omic data of 9,125 tumorsamples across 33 cancer types from The CancerGenome Atlas, we perform comprehensive molecu-lar characterization of 929 ubiquitin-related genesand 95 deubiquitinase genes. Among them, we sys-tematically identify top somatic driver candidates,including mutatedFBXW7with cancer-type-specificpatterns and amplifiedMDM2showing a mutuallyexclusive pattern withBRAFmutations. Ubiquitinpathway genes tend to be upregulated in cancermediated by diverse mechanisms. By integratingpan-cancer multiomic data, we identify a group oftumor samples that exhibit worse prognosis. Thesesamples are consistently associated with the upre-gulation of cell-cycle and DNA repair pathways, char-acterized by mutatedTP53,MYC/TERTamplifica-tion, andAPC/PTENdeletion. Our analysishighlights the importance of the ubiquitin pathwayin cancer development and lays a foundation fordeveloping relevant therapeutic strategies

    The Cancer Genome Atlas Comprehensive Molecular Characterization of Renal Cell Carcinoma

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