794 research outputs found
La cuestión de la frecuencia y el tipo de trato con inmigrantes: una aproximación a los efectos de las relaciones intergrupales sobre las actitudes hacia la inmigración
The goal of this report is to look in more depth at the effects that the relationships between indigenous people and immigrants can have on the attitudes of the former towards the latter. The study uses the results of a national opinion poll on the perception of Spaniards towards immigration. Following the traditional perspective of contact theory developed by G.W. Allport, two central questions are posed here: first, if more frequent contact between indigenous and immigrantcommunities brings with it a more positive perception of the migratoryphenomenon and second, if the type of relationship established between the two groups influences this perception. In other words, to what extent does intergroup contact contribute to reducing stereotypes and prejudices towards immigrants
High fragmentation characterizes tumour-derived circulating DNA.
BACKGROUND: Circulating DNA (ctDNA) is acknowledged as a potential diagnostic tool for various cancers including colorectal cancer, especially when considering the detection of mutations. Certainly due to lack of normalization of the experimental conditions, previous reports present many discrepancies and contradictory data on the analysis of the concentration of total ctDNA and on the proportion of tumour-derived ctDNA fragments. METHODOLOGY: In order to rigorously analyse ctDNA, we thoroughly investigated ctDNA size distribution. We used a highly specific Q-PCR assay and athymic nude mice xenografted with SW620 or HT29 human colon cancer cells, and we correlated our results by examining plasma from metastatic CRC patients. CONCLUSION/SIGNIFICANCE: Fragmentation and concentration of tumour-derived ctDNA is positively correlated with tumour weight. CtDNA quantification by Q-PCR depends on the amplified target length and is optimal for 60-100 bp fragments. Q-PCR analysis of plasma samples from xenografted mice and cancer patients showed that tumour-derived ctDNA exhibits a specific amount profile based on ctDNA size and significant higher ctDNA fragmentation. Metastatic colorectal patients (n = 12) showed nearly 5-fold higher mean ctDNA fragmentation than healthy individuals (n = 16)
EFHC1 variants in juvenile myoclonic epilepsy: reanalysis according to NHGRI and ACMG guidelines for assigning disease causality
Peer reviewe
In situ production of active vitamin B12 in cereal matrices using Propionibacterium freudenreichii
The in situ production of active vitamin B12 was investigated in aqueous cereal-based matrices with three strains of food-grade Propionibacterium freudenreichii. Matrices prepared from malted barley flour (33% w/v; BM), barley flour (6%; BF), and wheat aleurone (15%; AM) were fermented. The effect of cobalt and the lower ligand 5,6-dimethylbenzimidazole (DMBI) or its natural precursors (riboflavin and nicotinamide) on active B12 production was evaluated. Active B12 production was confirmed by UHPLC-UV-MS analysis. A B12 content of 12-37 mu g.kg(-1) was produced in BM; this content increased 10-fold with cobalt and reached 940-1,480 mu g.kg(-1) with both cobalt and DMBI. With riboflavin and nicotinamide, B12 production in cobalt-supplemented BM increased to 712 mu g.kg(-1). Approximately, 10 mu g.kg(-1) was achieved in BF and AM and was increased to 80 mu g.kg(-1) in BF and 260 mu g.kg(-1) in AM with cobalt and DMBI. The UHPLC and microbiological assay (MBA) results agreed when both cobalt and DMBI or riboflavin and nicotinamide were supplemented. However, MBA gave ca. 20%-40% higher results in BM and AM supplemented with cobalt, indicating the presence of human inactive analogues, such as pseudovitamin B12. This study demonstrates that cereal products can be naturally fortified with active B12 to a nutritionally relevant level by fermenting with P. freudenreichii.Peer reviewe
The Lower Carboniferous of the western edge of Gondwana in Peru and Bolivia: distribution of sedimentary basins and associated magmatism
During the Early Carboniferous, the tectono-sedimentary and magmatic configuration of the western edge of Gondwana (Eastern Cordillera of Peru and Cordillera Real of Bolivia, between latitudes 3°S and 24°S) associated a marine and continental sedimentation (Ambo Group), a volcanic arc (Lavasen Formation) and a related plutonism (Pataz-Balsas-Buldibuyo batholith, Higueras pluton, Amparaes and Cadenas granites). The present paper analyses the distribution of the Carboniferous basins and their relationships with Carboniferous magmatism along the western edge of Gondwana
The equilibrium shape of (65) Cybele: primordial or relic of a large impact?
Context. Cybele asteroids constitute an appealing reservoir of primitive material genetically linked to the outer Solar System, and the physical properties (size and shape) of the largest members can be readily accessed by large (8m class) telescopes. Aims. We took advantage of the bright apparition of the most iconic member of the Cybele population, (65) Cybele, in July and August 2021 to acquire high-angular-resolution images and optical light curves of the asteroid with which we aim to analyse its shape and bulk properties. Methods. Eight series of images were acquired with VLT/SPHERE+ZIMPOL, seven of which were combined with optical light curves to reconstruct the shape of the asteroid using the ADAM, MPCD, and SAGE algorithms. The origin of the shape was investigated by means of N-body simulations. Results. Cybele has a volume-equivalent diameter of 263±3 km and a bulk density of 1.55 ± 0.19 g cm−3. Notably, its shape and rotation state are closely compatible with those of a Maclaurin equilibrium figure. The lack of a collisional family associated with Cybele and the higher bulk density of that body with respect to other large P-type asteroids suggest that it never experienced any large disruptive impact followed by rapid re-accumulation. This would imply that its present-day shape represents the original one. However, numerical integration of the long-term dynamical evolution of a hypothetical family of Cybele shows that it is dispersed by gravitational perturbations and chaotic diffusion over gigayears of evolution. Conclusions. The very close match between Cybele and an equilibrium figure opens up the possibility that D ≥ 260 km (M ≥ 1.5 × 1019 kg) small bodies from the outer Solar System all formed at equilibrium. However, we cannot currently rule out an old impact as the origin of the equilibrium shape of Cybele. Cybele itself is found to be dynamically unstable, implying that it was ‘recently’ (<1 Gyr ago) placed on its current orbit either through slow diffusion from a relatively stable orbit in the Cybele region or, less likely, from an unstable, Jupiter-family-comet orbit in the planet-crossing region.This work has been supported by the Czech Science Foundation through grants 20-08218S (J. Hanuš) and 21-11058S (M. Brož), as well as by the National Science Foundation under Grant No. 1743015 (F. Marchis). T. Santana-Ros acknowledges funding from the NEO-MAPP project (H2020-EU-2-1-6/870377). In addition, this work was partially funded by the Spanish MICIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe” by the “European Union” through grant RTI2018-095076-B-C21, and the Institute of Cosmos Sciences University of Barcelona (ICCUB, Unidad de Excelencia ‘María de Maeztu’) through grant CEX2019-000918-M. This research has made use of the Asteroid Families Portal maintained at the Department of Astronomy, University of Belgrade. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liège, in collaboration with the Cadi Ayyad University of Marrakech (Morocco). E. Jehin is F.R.S.-FNRS Senior Research Associate
Intertexte et arrière-texte : les coulisses du littéraire
L'intertextualité avait fait l'objet en 2005-2006 de la session inaugurale du séminaire Approches Interdisciplinaires de la Lecture (AIL1). Si le concept demeure central pour appréhender le processus de création littéraire, peut-être n'est-il pas suffisant. L’arrière-texte entrevu en 2008-2009 serait-il le complément attendu et l’outil nécessaire pour penser la complexité ? Telle est la voie nouvelle explorée lors de la session 2009-2010 dans les deux domaines de la poésie et du roman. Les communications reprises dans le présent volume en restituent l’essentiel. L’arrière-texte procède, non de la théorie pure, mais de l’intuition d’écrivains nourris de deux cultures, russe et française. Il désigne tout ce qui se trouve en amont de la création littéraire, appréhendée selon ses deux versants auctorial et lectoral. On peut le concevoir comme le réseau d’associations présidant à l’effet littérature : associations verbales, sensorielles, cognitives, qui englobent et dépassent le phénomène d’intertextualité
Origin and quantification of circulating DNA in mice with human colorectal cancer xenografts
Although circulating DNA (ctDNA) could be an attractive tool for early cancer detection, diagnosis, prognosis, monitoring or prediction of response to therapies, knowledge on its origin, form and rate of release is poor and often contradictory. Here, we describe an experimental system to systematically examine these aspects. Nude mice were xenografted with human HT29 or SW620 colorectal carcinoma (CRC) cells and ctDNA was analyzed by Q–PCR with highly specific and sensitive primer sets at different times post-graft. We could discriminate ctDNA from normal (murine) cells and from mutated and non-mutated tumor (human) cells by using species-specific KRAS or PSAT1 primers and by assessing the presence of the BRAF V600E mutation. The concentration of human (mutated and non-mutated) ctDNA increased significantly with tumor growth. Conversely, and differently from previous studies, low, constant level of mouse ctDNA was observed, thus facilitating the study of mutated and non-mutated tumor derived ctDNA. Finally, analysis of ctDNA fragmentation confirmed the predominance of low-size fragments among tumor ctDNA from mice with bigger tumors. Higher ctDNA fragmentation was also observed in plasma samples from three metastatic CRC patients in comparison to healthy individuals. Our data confirm the predominance of mononucleosome-derived fragments in plasma from xenografted animals and, as a consequence, of apoptosis as a source of ctDNA, in particular for tumor-derived ctDNA. Altogether, our results suggest that ctDNA features vary during CRC tumor development and our experimental system might be a useful tool to follow such variations
Prognostic Significance of MYC Rearrangement and Translocation Partner in Diffuse Large B-Cell Lymphoma : A Study by the Lunenburg Lymphoma Biomarker Consortium
PURPOSE: MYC rearrangement (MYC-R) occurs in approximately 10% of diffuse large B-cell lymphomas (DLBCLs) and has been associated with poor prognosis in many studies. The impact of MYC-R on prognosis may be influenced by the MYC partner gene (immunoglobulin [IG] or a non-IG gene). We evaluated a large cohort of patients through the Lunenburg Lymphoma Biomarker Consortium to validate the prognostic significance of MYC-R (single-, double-, and triple-hit status) in DLBCL within the context of the MYC partner gene. METHODS: The study cohort included patients with histologically confirmed DLBCL morphology derived from large prospective trials and patient registries in Europe and North America who were uniformly treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone therapy or the like. Fluorescence in situ hybridization for the MYC, BCL2, BCL6, and IG heavy and light chain loci was used, and results were correlated with clinical outcomes. RESULTS: A total of 5,117 patients were identified of whom 2,383 (47%) had biopsy material available to assess for MYC-R. MYC-R was present in 264 (11%) of 2,383 patients and was associated with a significantly shorter progression-free and overall survival, with a strong time-dependent effect within the first 24 months after diagnosis. The adverse prognostic impact of MYC-R was only evident in patients with a concurrent rearrangement of BCL2 and/or BCL6 and an IG partner (hazard ratio, 2.4; 95% CI, 1.6 to 3.6; P < .001). CONCLUSION: The negative prognostic impact of MYC-R in DLBCL is largely observed in patients with MYC double hit/triple-hit disease in which MYC is translocated to an IG partner, and this effect is restricted to the first 2 years after diagnosis. Our results suggest that diagnostic strategies should be adopted to identify this high-risk cohort, and risk-adjusted therapeutic approaches should be refined further
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