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The aim of the present contribution is to describe the first ornithischian species from the Huincul Formation (Cenomanian-Turonian, Upper Cretaceous) at the Pueblo Blanco Natural Reserve, Río Negro province, Argentina. The new species, named Chakisaurus nekul gen. et sp. nov., can be comfortably included among elasmarian ornithopods. The new species shows humeral anatomy that is congruent with smaller members of the clade (e.g. Anabisetia, Notohypsilophodon), and differs from larger taxa (e.g. Talenkauen, Mahuidacursor) which show humeral features probably related with graviportal habits, such as lack of shaft torsion and a distally located deltopectoral crest. This indicates that graviportal habits were probably acquired independently in elasmarians from other large-sized taxa, such as hadrosauroids. Caudal vertebrae of the new species also show a unique combination of characters shared with other elasmarians, which are absent in previously known ornithopods. These features indicate that some elasmarians had a protonic tail posture, which is unknown in other ornithischians and was previously considered unique to derived titanosaurian sauropods. The shape of transverse processes and neural spines of caudal vertebrae indicate that at least some elasmarians had improved cursorial habilities, that were convergently acquired by selected theropod clades. [ABSTRACT FROM AUTHOR]

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The Cerro Fortaleza Formation is a stratigraphic unit that crops out near the Cerro Fortaleza hill, northwestern Santa Cruz province, Argentina. This unit has been well-known since the end of the XIX century, and because of the finding of abundant dinosaur bones, it was named as the "Capas con dinosaurios" (=Dinosaur Beds). Intensive work since the end of the 1990's resulted in the finding of diverse dinosaur species and other vertebrates. The fossil assemblage recovered includes lamniform sharks, lepisosteiforms, the dipnoan Atlantoceratodus iheringi , chelid turtles, peirosaurid crocodyliforms, mosasaur teeth, and diverse dinosaur remains. Dinosaurs include a partial tail of a small-sized titanosauriform, and another, identified as Dreadnoughtus , shows derived procoelous caudals. Isolated sauropod teeth indicate the presence of a derived lithostrotian and the enigmatic Clasmodosaurus spatula Ameghino, 1899. Among theropods, abelisaurid and megaraptorids are reported. A partial ulna, manual claw and metatarsal belonging to the holotype of the enigmatic theropod Austrocheirus isasii are also described. The morphology of the new elements does not comfortably fit with abelisaurid or megaraptorid theropods, and the affinities of Austrocheirus among theropods still remain elusive. The fossil vertebrate content of the Cerro Fortaleza Formation indicates close similarities with the faunistic assemblage previously reported from the Mata Amarilla Formation (Cenomanian-Turonian), and strong differences are present with the overlying Chorrillo Formation (Maastrichtian). This may indicate that some kind of change among terrestrial vertebrates occurred at the Campanian/Maastrichtian boundary in the Austral Patagonia Basin. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is one of the most prevalent tumors worldwide, with incidence quickly increasing (particularly in the context of early-onset cases), despite important prevention efforts, mainly in the form of population-wide screening programs. Although many cases present a clear familial component, the current list of hereditary CRC genes leaves a considerable proportion of the cases unexplained. In this work, we used whole-exome sequencing approaches on 19 unrelated patients with unexplained colonic polyposis to identify candidate CRC predisposition genes. The candidate genes were then validated in an additional series of 365 patients. CRISPR-Cas9 models were used to validate BMPR2 as a potential candidate for CRC risk. We found 8 individuals carrying 6 different variants in the BMPR2 gene (approximately 2% of our cohort of patients with unexplained colonic polyposis). CRISPR-Cas9 models of 3 of these variants showed that the p.(Asn442Thr fs ∗32) truncating variant completely abrogated BMP pathway function in a similar way to the BMPR2 knockout. Missense variants p.(Asn565Ser), p.(Ser967Pro) had varying effects on cell proliferation levels, with the former impairing cell control inhibition via noncanonical pathways. Collectively, these results support loss-of-function BMPR2 variants as candidates to be involved in CRC germline predisposition. [Display omitted] Variants in the BMPR2 gene affect molecular processes that could increase the risk of developing colonic polyposis and colorectal cancer. [ABSTRACT FROM AUTHOR]

Chucarosaurus diripienda gen. et sp. nov. is a new and large titanosaurian sauropod from the Neuquén Basin, Rio Negro Province, Patagonia. The specimen was discovered in the Upper Cretaceous strata of the Huincul Formation (middle Cenomanian–lower Turonian). It includes appendicular and relatively slender elements, with a femoral total length of about 1.9 m long. This taxon shows a unique combination of characters indicating that appendicular bones such as the femur, ischium and tibia, show a remarkable morphological variety, greater than previously described, and are morphologically informative as source of phylogenetic data. A cladistic phylogenetic analysis placed Chucarosaurus well nested within the Colossosauria clade. [ABSTRACT FROM AUTHOR]

Enantiornithes were the dominant avialan clade in the Mesozoic. However, their record for the Upper Cretaceous is scarce. In this study, we present and describe Yatenavis ieujensis gen. et sp. nov., one of the youngest occurrence of an enantiornithine bird. The specimen, the distal half of a right humerus, was found in Chorrillo Formation, southern Santa Cruz Province of Argentina, making it also the australmost enantiornithine specimen recorded to date. Yatenavis is unique among enantiornithines for its combination of characters, including a crest on the medial side of the shaft which bears a muscular scar cranially; the presence of a dorsal supracondylar process proximal to the dorsal epicondyle; equally distally projected dorsal and ventral condyles; and a rod-like caudal extension of the ventral condyle bearing a distal sulcus scapulotricipitalis. Several of these features are shared with an unnamed enantiornithine recovered from Upper Cretaceous beds in another fossil site in Patagonia. [ABSTRACT FROM AUTHOR]

A new ornithopod dinosaur from the Upper Cretaceous (Maastrichtian) Snow Hill Island Formation, at James Ross Island, Antarctica is here described. This new taxon, named as Morrosaurus antarcticus gen. et sp. nov., is represented by a fragmentary right hind limb belonging to a medium-sized individual. Our phylogenetic analysis nests the new taxon in a monophyletic clade of Southern Hemisphere ornithopods that includes most Patagonian and Antarctic ornithopods. Several members of this group share a slender and bunched foot with narrow metatarsal IV, expanded chevrons, and bowed humerus without deltopectoral crest. Several features indicate that these ornithopods exhibit adaptations for a specialized cursorial mode of life. The recognition of Patagonian and Antarctic Ornithopoda belonging to a monophyletic clade reinforces palaeobiogeographical signals indicating that Patagonia, Antarctica and Australia shared a common Late Cretaceous terrestrial fauna. [ABSTRACT FROM AUTHOR]

The article presents a study which analyzed the use of colorectal cancer susceptibility quantitative trait loci in mice in the detection of low-pentrance variants in humans. The researchers analyzed the structure of the single-nucleotide polymorphism rs954353 which is one of the important factors in the diagnosis of colorectal cancer. They believed that the candidate gene selection strategy used in this research can still be useful in the future identification of the variants predisposing to the medical condition.

The deposits of the Chorrillo Formation (Maastrichtian) were accumulated during a 'continental window' that occurred during the Late Cretaceous in the Austral-Magallanes foreland basin, southern Patagonia, Argentina. The aim of the present contribution is to describe the depositional conditions as well as new vertebrate and plant fossils from this unit. The analysis of these deposits resulted in the definition of five architectural elements: Complex sandy narrow sheets channels (SS), Complex gravelly narrow sheets channels (GS), Sandstone lobes (SL), Thick fine-grained deposits (GF) and Thin dark fine-grained deposits (DF). These were separated into channelized and non-channelized units and represent the accumulation in a fine-grained dominated, fossil rich fluvial depositional system. Vertebrates fossil records include two species of frogs of the genus Calypteocephalella (representing the southernmost record of Pipoidea), snakes belonging to Madtsoiidae and Anilioidea (the latter ones being the first records for the basin), chelid turtles similar to Yaminuechelys - Hydromedusa , meiolaniiform turtles, titanosaur sauropods, megaraptoran theropods, new remains of the elasmarian Isasicursor santacrucensis (including the first cranial remains available for this species), hadrosaur ornithischians, enantiornithine birds. Sharks and elasmosaurs are also recorded and may possibly derive from the overlying marine Calafate Formation. These new taxa, together with previous findings from the Chorrillo Formation, are included into a stratigraphic column, thus providing valuable information that sheds new light on faunistic composition and paleobiogeography of high-latitude biotas of Gondwana. • The depositional architectural elements and the paleontological content from the Chorrillo Formation are described. • The Chorrillo Formation is interpreted as accumulated in a fluvial depositional system dominated by fine-grained deposits. • The continentalization of the basin provided new ecological niches for plants and vertebrates. • The fossil vertebrates association matches with the one reported from the Dorotea Formation. [ABSTRACT FROM AUTHOR]

The record of sauropods in the Upper Cretaceous of Patagonia is rich. However, there are still several blanks on this record. Here it is described a new sauropod assemblage coming from the Salitral Ojo de Agua Area, Río Negro province, northern Patagonia, Argentina (Allen Formation; Maastrichtian). Remains of indeterminate saltasaurines, aeolosaurines, as well as new specimens of the small saltasaurine Rocasaurus muniozi and the new eutitanosaur Menucocelsior arriagadai gen. et sp. nov., are described. The new eutitanosaur is represented by an incomplete caudal series and some appendicular bones that indicate that it does not belong to any previously recognized eutitanosaur clade (e.g, Colossosauria, Saltasaurinae, Aeolosaurini). The co-occurrence of several roughly coeval titanosaurs in a restricted area (as occur in Bajo de Santa Rosa, Salitral Moreno and Salitral Ojo de Agua sites) with different body plans, indicates that they probably occupied particular ecological niches and that probably competition for resources was limited, allowing the connivance of several taxa in a single locality and age. This pattern is not observed in other sites of the world. Based on these records and on the high diversity of osteoderm morphotypes recovered, it appears to be certain that palaeoecological conditions in the area were able to sustain and promote the flourishing of many species of titanosaurs. • A description of a new sauropod fauna from the Maastrichtian of Patagonia. • The publication of the new big-sized titanosaurid species. • The publication of new bones of saltasaurid materials for the Later Cretaceous of Argentina. • A detailed description of associated osteoderms assigned to titanosaurs or saltasaurines. • The comparisons between the sauropod faunas from the different basins of Patagonia. [ABSTRACT FROM AUTHOR]

The fossil record of ornithischians in South America is sparse, and they are clearly underrepresented when compared with sauropod dinosaurs. However, recent discoveries indicate that ornithischians were more diversified than thought. The aim of the present contribution is to describe isolated remains belonging to ankylosaurs and ornithopods, including basal euiguanodontians and hadrosaurs coming from the Chorrillo Formation (upper Campanian – lower Maastrichtian), Santa Cruz province, southern Argentina. The fossil remains of ankylosaurs reported here are the southernmost recorded for the continent. They show a unique combination of plesiomorphic features, indicating that they may belong to a basal ankylosaur. Ankylosaurs and hadrosaurids are thought to have arrived in South America during the latest Cretaceous through Central America. However, a detailed overview of the fossil record of Gondwana indicates that both clades were present and probably diversified across southern continents. This indicates that their presence in South America may be alternatively interpreted as the result of migration from other landmasses, including Africa and Europe, or may even be the result of Jurassic – Early Cretaceous vicariance from their northern counterparts. • New ankylosaur remains for South America representing a small sized animal with long bones and osteoderms. • A new representative of the Gasparinisaura clade is here reported, extending this group of ornithopods to the Maastrichtian southern Patagonia. • The discovery of hadrosaurs allow us to correlate Chorrillo Formation with the adjacent Chilean Dorotea Formation. • The presence of four ornithischian taxa in the Chorrillo Formation erect this as the more diverse Formation in this dinosaurs in South America. [ABSTRACT FROM AUTHOR]

The bone histology of the Antarctic ornithopods Trinisaura santamartaensis and Morrosaurus antarcticus from the Upper Cretaceous (Campanian-Maastrichtian) is here studied. With the purpose to obtain information regarding their growth pattern, we analyse the bone histology of appendicular elements from the holotype specimens of both species. The cortical bone of the studied elements is constituted by fibro-lamellar tissue, with vascular canals mostly showing in a longitudinal and reticular arrangement, suggesting an accelerated growth. The cortical bone tissue is interrupted by lines of arrested growth (LAGs) and annuli. The study reveals that both the holotypes of Trinisaura and Morrosaurus were sexually mature subadults at the time of death (i.e. they died before reach somatic maturity). The growth pattern of these Antarctic ornithopods is similar to that reported for the related taxon Gasparinisaura , which lived in lower latitudes, as well as for the Australian ornithopods, taxa that inhabited polar latitudes during the Early Cretaceous. This contrasts with the pattern reported for more derived ornithopods (i.e. hadrosaurids) and ceratopsians from the Northern Hemisphere, whose growth dynamics vary in different latitudes. In this regard, Gondwanan ornithopods would present a preadaptation for endure in environments with great temperature changes along the year. [ABSTRACT FROM AUTHOR]

Macrogryphosaurus gondwanicus is the largest Elasmaria (Dinosauria, Ornithischia) known up to the date, from the Upper Cretaceous of Patagonia. The present contribution provides a detailed description of Macrogryphosaurus anatomy based on the holotype and only known specimen. This dinosaur presents several unique features along its vertebral column that distinguishes it from other ornithopods: the neck is notably elongated by the acquisition of an additional cervical vertebra, having 10 cervical plus 14 dorsal vertebrae, being the number of dorsals minor than in other taxa, which usually have 16. This implies that Macrogryphosaurus represents a new ornithopod morphotype, with long neck and short thorax. Moreover, three autapomorphies are here added to the original diagnosis of Macrogryphosaurus : presence of poorly developed diapophyses in the cervical vertebrae, anterior and posterior processes on the boat-shaped haemal arches, and a pubic foot in the postpubic process. The dorsoventral length of haemal arches indicate the ventral limit of the M. caudofemoralis longus and their posterior tapering so as the dorsal limit of the M. ilio-ischiocaudalis and its posterior ascension and dominance in the posterior-most portion of tail, resembling to the tail of some coelurosaur dinosaurs. [ABSTRACT FROM AUTHOR]

Background & Aims: Ten common low-penetrant genetic variants have been consistently associated with colorectal cancer (CRC) risk; little is known about the correlation between these variants and CRC phenotype. Characterization of such a correlation would improve CRC management and prevention programs. We assessed the association between these genetic variants and CRC phenotype in patients and modeled pairwise combinations to detect epistasis. Methods: The validation population corresponded to a prospective, multicenter, population-based cohort (EPICOLON I) of 1096 patients with newly diagnosed CRC. The replication set was an independent, prospective, multicenter Spanish cohort (EPICOLON II) of 895 patients with newly diagnosed CRC. For individual single nucleotide polymorphism (SNP) association analyses, a multivariate method using logistic regression was applied in EPICOLON I and subsequently prospectively validated in EPICOLON II. Interactions between SNPs were assessed using the likelihood ratio test. Results: Validated results confirmed that the C allele on 8q23.3 (rs16892766) was significantly associated with advanced-stage tumors (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.15–1.90; P value = 4.9 × 10−3). The G allele on 8q24.21 (rs6983267) was more common in patients with a familial history of CRC (OR, 2.02; 95% CI, 1.35–3.03; P value = 3.9 × 10−4). The combination of rs6983267 on 8q24.21 and rs9929218 on 16q22.2 was associated with a history of colorectal adenoma (carriers of GG and AA, respectively; OR, 2.28; 95% CI, 1.32–3.93; P = 5.0 × 10−4). Conclusions: CRC susceptibility variants at 8q23.3, 8q24.21, and 16q22.2 appear to be associated with cancer phenotype. These findings might be used to develop screening and surveillance strategies. [Copyright &y& Elsevier]