209 research outputs found

    Structural, mechanical and electronic properties of two-dimensional structure of III-arsenide (1 1 1) binary compounds: An ab-initio study

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    Structural, mechanical and electronic properties of two-dimensional single-layer hexagonal structures in the (1 1 1) crystal plane of IIIAs-ZnS systems (III = B, Ga and In) are studied by first-principles calculations based on density functional theory (DFT). Elastic and phonon dispersion relation display that 2D h-IIIAs systems (III = B, Ga and In) are both mechanical and dynamically stable. Electronic structures analysis show that the semiconducting nature of the 3D-IIIAs compounds is retained by their 2D single layer counterpart. Furthermore, density of states reveals the influence of σ and π bonding in the most stable geometry (planar or buckled) for 2D h-IIIAs systems. Calculations of elastic constants show that the Young's modulus, bulk modulus and shear modulus decrease for 2D h-IIIAs binary compounds as we move down on the group of elements of the periodic table. In addition, as the bond length between the neighboring cation-anion atoms increases, the 2D h-IIIAs binary compounds display less stiffness and more plasticity. Our findings can be used to understand the contribution of the σ and π bonding in the most stable geometry (planar o buckled) for 2D h-IIIAs systems. Structural and electronic properties of h-IIIAs systems as a function of the number of layers have been also studied. It is shown that h-BAs keeps its planar geometry while both h-GAs and h-InAs retained their buckled ones obtained by their single layers. Bilayer h-IIIAs present the same bandgap nature of their counterpart in 3D. As the number of layers increase from 2 to 4, the bandgap width for layered h-IIIAs decreases until they become semimetal or metal. Interestingly, these results are different to those found for layered h-GaN. The results presented in this study for single and few-layer h-IIIAs structures could give some physical insights for further theoretical and experimental studies of 2D h-IIIV-like systems

    cis-Bis(N-benzoyl-N′,N′-dibenzyl­thio­ureato-κ2 O,S)nickel(II)

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    In the title compound, [Ni(C22H19N2OS)2], the NiII atom is coordinated by the S and O atoms of two N-benzoyl-N′,N′-dibenzyl­thio­ureate ligands in a slightly distorted square-planar geometry. The two O atoms are cis, as are the two S atoms

    Papel de la eminencia talámica, el sistema olfativo principal y el sistema olfativo accesorio en la maduración sexual del encéfalo y las manifestaciones clínico-morfológicas del síndrome de Kallmann

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    El desarrollo de sistema olfativo y la diferenciación sexual del encéfalo, tanto en el hombre como en los animales, están estrechamente relacionados. Actualmente, se describe la imbricación entre la formación del sistema olfativo principal y la migración de las neuronas que sintetizan la hormona liberadora de gonadotrofinas (GnRF). Estas neuronas GnRF se desplazan por los nervios olfatorios, desde la parte medial del epitelio nasal al bulbo olfatorio, continúan por el encéfalo rostral hasta alcanzar el hipotálamo anterior. Por otro lado, el síndrome de Kallmann es un trastorno genético en el cual se combina el hipogonadismo hipogonadotrópico y la anosmia. El hipogonadismo se caracteriza por la ausencia o reducción de los niveles de hormona liberadora de gonadotrofinas y la anosmia la aplasia del bulbo olfatorio. En esta revisión se analizan las estructuras responsables de la maduración del sistema olfativo principal y accesorio, la diferenciación sexual del encéfalo y su relación con todas las manifestaciones clínicas y morfológicas del síndrome Kallmann. The olfactory system development and brain sexual maturation, in man and animals, are closely related. Currently the overlap between the formation of the olfactory system and the migration of neurons that synthesize gonadotropin-releasing hormone (GnRF) are described. The GnRF neurons migrate from the medial portion of the nasal epithelium through the olfactory nerves and the main olfactory bulb to the anterior hypothalamus. Furthermore, Kallmann syndrome (KS) is a genetic disorder in which combines hypogonadotropic hypogonadism and anosmia. Hypogonadism is characterized by the absence or reduced levels of gonadotropin-releasing hormone and anosmia is due to aplasia of the olfactory bulb. The basic clinical manifestations of KS are: anosmia and the absence of puberty. The structures responsible for the maturation of the main and accessory olfactory systems, the sexual differentiation of the brain and its relationship with all the clinical manifestations of Kallmann syndrome are analyzed in this revie

    Supply of essential and nonessential amino acids, proteins, antioxidants, iron and zinc from the main varieties of beans consumed in Mexico and their potential for biofortification

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    The objective of the present study was to characterize the contribution of essential and non-essential amino acids, protein, iron (Fe), and zinc (Zn) concentration, and antioxidant activity of the main bean varieties produced and consumed in Mexico. 23 varieties of beans were selected, and their amino acid profile, Fe and Zn concentration, protein and antioxidant activity were evaluated. The data obtained were subjected to an analysis of variance, test of separation of means and a correlation analysis. The results obtained indicate that the beans analyzed are an excellent source of essential amino acids (Histidine, threonine, valine, methionine, lysine, isoleucine, leucine and phenylalanine) and non-essential amino acids (Aspartic acid, serine, glutamic acid, glycine, alanine, proline, cysteine, tyrosine and arginine). The most prominent amino acids in Mexican bean varieties were: Glutamic acid, proline, aspartic acid, serine, lysine, and leucine. Regarding antioxidant activity, the most outstanding concentrations ranged from 91.18 to 96.76% inhibition. The bean varieties with the highest accumulation of amino acids, proteins, Fe, Zn and antioxidant activity were: 1) Black-eyed (23); 2) Peruvian (154); 3) Flor de Junio (150); 4) Pinto Saltillo (155). Finally, it was found that the common bean (Phaseolus vulgaris L.) is an excellent vehicle for the biofortification of Fe and Zn, which can contribute significantly to combat malnutrition problems and health of vulnerable communities in the urban and rural sectors of Mexico, as well as in the developing countries of the world

    Is it necessary to show virtual limbs in action observation neurorehabilitation systems?

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    Action observation neurorehabilitation systems are usually based on the observation of a virtual limb performing different kinds of actions. In this way, the activity in the frontoparietal Mirror Neuron System is enhanced, which can be helpful to rehabilitate stroke patients. However, the presence of limbs in such systems might not be necessary to produce mirror activity, for example, frontoparietal mirror activity can be produced just by the observation of virtual tool movements. The objective of this work was to explore to what point the presence of a virtual limb impacts the Mirror Neuron System activity in neurorehabilitation systems.info:eu-repo/semantics/publishedVersio

    Quality More Than Quantity: The Use of Carbohydrates in High-Fat Diets to Tackle Obesity in Growing Rats

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    This research was supported by funds provided by the Abbott Laboratories S.A.Childhood obesity prevention is important to avoid obesity and its comorbidities into adulthood. Although the energy density of food has been considered a main obesogenic factor, a focus on food quality rather that the quantity of the different macronutrients is needed. Therefore, this study investigates the effects of changing the quality of carbohydrates from rapidly to slowly digestible carbohydrates on metabolic abnormalities and its impact on obesity in growing rats fed a high-fat diet (HFD). Growing rats were fed on HFD containing carbohydrates with different digestion rates: a HFD containing rapid-digesting carbohydrates (OBE group) or slow-digesting carbohydrates (ISR group), for 4 weeks and the effect on the metabolism and signaling pathways were analyzed in different tissues. Animals from OBE group presented an overweight/obese phenotype with a higher body weight gain and greater accumulation of fat in adipose tissue and liver. This state was associated with an increase of HOMA index, serum diacylglycerols and triacylglycerides, insulin, leptin, and pro-inflammatory cytokines. In contrast, the change of carbohydrate profile in the diet to one based on slow digestible prevented the obesity-related adverse effects. In adipose tissue, GLUT4 was increased and UCPs and PPARg were decreased in ISR group respect to OBE group. In liver, GLUT2, FAS, and SRBP1 were lower in ISR group than OBE group. In muscle, an increase of glycogen, GLUT4, AMPK, and Akt were observed in comparison to OBE group. In conclusion, this study demonstrates that the replacement of rapidly digestible carbohydrates for slowly digestible carbohydrates within a highfat diet promoted a protective effect against the development of obesity and its associated comorbidities.Abbott Laboratories S.A

    TRAF3 alterations are frequent in del-3′IGH chronic lymphocytic leukemia patients and define a specific subgroup with adverse clinical features

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    Interstitial 14q32 deletions involving IGH gene are infrequent events in chronic lymphocytic leukemia (CLL), affecting less than 5% of patients. To date, little is known about their clinical impact and molecular underpinnings, and its mutational landscape is currently unknown. In this work, a total of 871 CLLs were tested for the IGH break-apart probe, and 54 (6.2%) had a 300 kb deletion of 3′IGH (del-3′IGH CLLs), which contributed to a shorter time to first treatment (TFT). The mutational analysis by next-generation sequencing of 317 untreated CLLs (54 del-3′IGH and 263 as the control group) showed high mutational frequencies of NOTCH1 (30%), ATM (20%), genes involved in the RAS signaling pathway (BRAF, KRAS, NRAS, and MAP2K1) (15%), and TRAF3 (13%) within del-3′IGH CLLs. Notably, the incidence of TRAF3 mutations was significantly higher in del-3′IGH CLLs than in the control group (p < .001). Copy number analysis also revealed that TRAF3 loss was highly enriched in CLLs with 14q deletion (p < .001), indicating a complete biallelic inactivation of this gene through deletion and mutation. Interestingly, the presence of mutations in the aforementioned genes negatively refined the prognosis of del-3′IGH CLLs in terms of overall survival (NOTCH1, ATM, and RAS signaling pathway genes) and TFT (TRAF3). Furthermore, TRAF3 biallelic inactivation constituted an independent risk factor for TFT in the entire CLL cohort. Altogether, our work demonstrates the distinct genetic landscape of del-3′IGH CLL with multiple molecular pathways affected, characterized by a TRAF3 biallelic inactivation that contributes to a marked poor outcome in this subgroup of patients.Funding information: Universidad de Salamanca; Fundación Española de Hematología y Hemoterapia (FEHH); Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Grant/Award Number: CB16/12/00233; Red Temática de Investigación Cooperativa en Cáncer (RTICC); “Fundación Memoria Don Samuel Solórzano Barruso”: FS/33–2020, Grant/Award Number: RD12/0036/0069; “Gerencia Regional de Salud, SACYL”:, Grant/Award Numbers: GRS2385/A/21, GRS2140/A/20; Consejería de Educación, Junta de Castilla y León, Grant/Award Number: SA118P20; European Regional Development Fund and Instituto de Salud Carlos III, Grant/Award Numbers: CD19/00222, FI19/00191; Spanish Fondo de Investigaciones Sanitarias, Grant/Award Numbers: PI21/00983, PI18/0150

    Dissecting the role of TP53 alterations in del(11q) chronic lymphocytic leukemia

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    © 2021 The Authors.[Background]: Several genetic alterations have been identified as driver events in chronic lymphocytic leukemia (CLL) pathogenesis and oncogenic evolution. Concurrent driver alterations usually coexist within the same tumoral clone, but how the cooperation of multiple genomic abnormalities contributes to disease progression remains poorly understood. Specifically, the biological and clinical consequences of concurrent high-risk alterations such as del(11q)/ATM-mutations and del(17p)/TP53-mutations have not been established.[Methods]: We integrated next-generation sequencing (NGS) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 techniques to characterize the in vitro and in vivo effects of concurrent monoallelic or biallelic ATM and/or TP53 alterations in CLL prognosis, clonal evolution, and therapy response.[Results]: Targeted sequencing analysis of the co-occurrence of high-risk alterations in 271 CLLs revealed that biallelic inactivation of both ATM and TP53 was mutually exclusive, whereas monoallelic del(11q) and TP53 alterations significantly co-occurred in a subset of CLL patients with a highly adverse clinical outcome. We determined the biological effects of combined del(11q), ATM and/or TP53 mutations in CRISPR/Cas9-edited CLL cell lines. Our results showed that the combination of monoallelic del(11q) and TP53 mutations in CLL cells led to a clonal advantage in vitro and in in vivo clonal competition experiments, whereas CLL cells harboring biallelic ATM and TP53 loss failed to compete in in vivo xenotransplants. Furthermore, we demonstrated that CLL cell lines harboring del(11q) and TP53 mutations show only partial responses to B cell receptor signaling inhibitors, but may potentially benefit from ATR inhibition.[Conclusions]: Our work highlights that combined monoallelic del(11q) and TP53 alterations coordinately contribute to clonal advantage and shorter overall survival in CLL.Spanish Fondo de Investigaciones Sanitarias, Grant/Award Numbers: PI15/01471, PI18/01500); Fundación Memoria Don Samuel Solórzano Barruso, Grant/Award Number: RD12/0036/006

    Minimal residual disease evaluation by flow cytometry is a complementary tool to cytogenetics for treatment decisions in acute myeloid leukaemia

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    For PETHEMA Programa para el Estudio de la Terapéutica en Hemopatías Malignas Cooperative Study Group.The clinical utility of minimal residual disease (MRD) analysis in acute myeloid leukaemia (AML) is not yet defined. We analysed the prognostic impact of MRD level at complete remision after induction therapy using multiparameter flow cytometry in 306 non-APL AML patients. First, we validated the prognostic value of MRD-thresholds we have previously proposed (≥0.1%; ≥0.01-0.1%; and <0.01), with a 5-year RFS of 38%, 50% and 71%, respectively (p = 0.002). Cytogenetics is the most relevant prognosis factor in AML, however intermediate risk cytogenetics represent a grey zone that require other biomarkers for risk stratification, and we show that MRD evaluation discriminate three prognostic subgroups (p = 0.03). Also, MRD assessments yielded relevant information on favourable and adverse cytogenetics, since patients with favourable cytogenetics and high MRD levels have poor prognosis and patients with adverse cytogenetics but undetectable MRD overcomes the adverse prognosis. Interestingly, in patients with intermediate or high MRD levels, intensification with transplant improved the outcome as compared with chemotherapy, while the type of intensification therapy did not influenced the outcome of patients with low MRD levels. Multivariate analysis revealed age, MRD and cytogenetics as independent variables. Moreover, a scoring system, easy in clinical practice, was generated based on MRD level and cytogenetics.This work was supported in part by Spanish grants from Fondo de Investigación Sanitaria-ISCIII (FIS 00/0023-03, PI12/02321), DGCYT (SAF 94- 0308, SAF2001-1687), Conserjería de Educación de Castilla y León (HUS416A12), and Red Temática de Investigación Cooperativa en Cáncer (RTICC-ISCIII) (RD12/0036/0069).Peer Reviewe
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