Synergistic Interactions of H\u3csub\u3e2\u3c/sub\u3e and N\u3csub\u3e2\u3c/sub\u3e with Molten Gallium in the Presence of Plasma

The present study examines the interaction of hydrogen and nitrogen plasmas with gallium in an effort to gain insights into the mechanisms behind the synergetic effect of plasma and a catalytic metal. Absorption/desorption experiments were performed, accompanied by theoretical-computational calculations. Experiments were carried out in a plasma-enhanced, Ga-packed, batch reactor and entailed monitoring the change in pressure at different temperatures. The results indicated a rapid adsorption/dissolution of the gas into the molten metal when gallium was exposed to plasma, even at a low temperature of 100 °C. The experimental observations, when hydrogen was used, indicate that gallium acts as a hydrogen sink in the presence of plasma. Similar results were obtained with Ga in the presence of nitrogen plasma. In addition, density functional theory calculations suggest a strong interaction between atomic hydrogen and molten gallium. This interaction is described as a high formation of Ga-H species on the surface, fast diffusion inside the metal, and a steady state concentration of the gas in the bulk

SHP-1 Associates with Both Platelet-derived Growth Factor Receptor and the p85 Subunit of Phosphatidylinositol 3-Kinase*

The Src homology 2 (SH2)-containing protein tyrosine phosphatase 1, SHP-1, is highly expressed in all hematopoietic cells as well as in many non-hematopoietic cells, particularly in some malignant epithelial cell lines. In hematopoietic cells, SHP-1 negatively regulates multiple cytokine receptor pathways. The precise function and the targets of SHP-1 in non-hematopoietic cells, however, are largely unknown. Here we demonstrate that SHP-1 associates with both the tyrosine-phosphorylated platelet-derived growth factor (PDGF) receptor and the p85 subunit of phosphatidylinositol 3-kinase in MCF-7 and TRMP cells. Through the use of mutant PDGF receptors and performing peptide competition for immunoprecipitation, it was determined that SHP-1 independently associates with the PDGF receptor and p85 and that its N-terminal SH2 domain is directly responsible for the interactions. Overexpression of SHP-1 in TRMP cells transfected with the PDGF receptor markedly inhibited PDGF-induced c-fos promoter activation, whereas the expression of three catalytically inactive SHP-1 mutants increased the c-fos promoter activation in response to PDGF stimulation. These results indicate that SHP-1 might negatively regulate PDGF receptor-mediated signaling in these cells. Identification of the association of SHP-1 with the PDGF receptor and p85 in MCF-7 and TRMP cells furthers our understanding of the function of SHP-1 in non-hematopoietic cells

PO-033 Identification and functional evaluation of monoclonal antibodies specifically targeting human carbonic anhydrase IX

Introduction Poor vascularisation of solid tumours leads to inadequate nutrient and oxygen supplies which forces tumour cells to reprogram their metabolism. As a consequence the tumour cell's environment becomes acidic and hypoxic. This, in turn, triggers signalling cascades involving for example heterodimeric hypoxia-inducible factor (HIF). Activation of this hypoxia-induced transcriptional program is crucial for the survival of tumour cells in their hostile microenvironment but also their ability to metastasize. One of the genes upregulated through the HIF pathway is carbonic anhydrase (CA)-IX (CAIX, gene G250/MN-encoded transmembrane protein). CA-IX catalyses carbon dioxide (CO2) thereby generating a proton (H+) and bicarbonate (HCO3-), the latter of which is transported back into the cell and utilised to help safeguard intracellular pH (pHi) stability. Except for the stomach and the gallbladder, CA-IX expression is negligible in normal tissues. In contrast, a broad range of tumours express high levels of CA-IX, where the protein can serve as a biomarker for the early stages of tumour development but also as tumour marker of hypoxia associated with resistance to chemotherapy and radiotherapy. Material and methods Preclinical and clinical studies have shown that CA-IX is a promising therapeutic target for detection and therapy for several cancer types. To date only a limited number of ant-CAIX monoclonal antibodies (mAbs) have been available for clinical testing as therapeutic and imaging agents. In the current study, we generated and functionally categorised a panel of 51 mouse mAbs that specifically bind to human CA-IX. Results and discussions Characterisation of the mAbs revealed that of the mAbs with the best biophysical characteristics, three3 mAbs are suitable as an antibody-drug conjugate (ADC), two2 mAbs inhibit the CA-IX enzyme activity, and one1 mAb that is suitable for CA-IX imaging purposes. Conclusion These preliminary data presented here could thus form the basis for the development of novel CA-IX targeted immunotherapies and diagnostic tools for the treatment of cancer

Kinetics of thermal degradation of carotenoids related to potential of mixture of wheat, cassava and sweet potato flours in baking products

BACKGROUND The consumption of foods such as sweet potato and cassava with high levels of carotenoids is a possible solution to reduce vitamin A deficiency. In this study, we evaluated the kinetics of thermal degradation of carotenoids. The content of carotenoids was quantified by HPLC, first in fresh material, then in flour, and finally in bakery products using mixtures of wheat, sweet potato and cassava. The degree of acceptance of the bakery products by children was also assessed through a sensory acceptance test. RESULTS The study found that the degradation of carotenoids compounds in sweet potato followed first-order kinetics and fit the Arrhenius equation with correlations of R2>0.9. The retention rates of all-trans-β-carotene were 77%, 56% and 48% at the cooking temperatures of 75°, 85° and 95°C respectively, during a cooking time of 20 min. The concentrations of all trans-β-carotene, after baking, for bread, cookies, and cake were 15, 19 and 14 μg/g db, respectively. In the sensory acceptance test carried out in a school, 47.6% of the boys and 79.2% of the girls rated the cookies made from a mixture of cassava, sweet potato, and wheat flour with the indicator, I like it a lot. CONCLUSION The content of carotenoids compounds was reduced by exposure to high temperatures and long cooking times. The combinations of cooking time and temperature which minimized degradation of all-trans-β-carotene occurred at 75°C-20 min and 95°C-10 min. All trans-β-carotene retentions for bread, cookies and cake were 25%, 15% and 11% respectively. The mixture of wheat-sweet potato-cassava flour can be considered in the development of cookies with positive contributions of all trans-β-carotenes and with a good acceptance by children between 9 and 13 years. This article is protected by copyright. All rights reserved

Use of a 3D virtual app and academic performance in the study of the anatomy of the musculoskeletal system among Peruvian medical students

Objective: To evaluate the association between the use of a 3D virtual App and academic performance among Peruvian medical students. In addition, factors associated with academic performance were also assessed. Methods: We conducted an analytical cross-sectional study in students enrolled in the Musculoskeletal System course during the first semester of 2019. Students filled out a data collection form and the "Self-directed learning readiness scale" (SDLRS) questionnaire adapted by Fisher, King, and Tangle. Linear regression models were carried out to assess the association between the appropriate use of the application and academic performance. Additionally, the factors associated with academic performance were evaluated using nested models, and beta coefficients were calculated by manual forward selection. Results: A total of 187 medical students were included. The 61% were female and the median age was 21 [20-22] years. The average grade was 13.5 +/- 2 and 21% reported an adequate use of a 3D App. No association was found between the use of the 3D App and academic performance in the adjusted model (a beta = 0.17; 95% CI: -0.45 to 0.80). We found that age (a beta = -0.22; 95% CI: -0.39 to -0.06), performing extracurricular activities (a beta = 0.75, 95% CI: 0.25 to 1.24) and having failed an anatomy/physiology course before (a beta = -2.11 to 95% CI: -2.9 to -1.8) were factors associated with academic performance. Conclusion: The adequate use of a 3D application to study the anatomy of the musculoskeletal system was not significantly associated with better academic performance.Revisión por pare

Clinical factors associated with high glycemic variability defined by coefficient of variation in patients with type 2 diabetes

Antecedentes: La Variabilidad Glucémica Alta (VHG) ha convertirse en un predictor más fuerte de hipoglucemia. Sin embargo, aún se desconocen los factores clínicos asociados con el VHG. Objetivo:Determinar las variables clínicas que se asociaron con un coeficiente de variación (CV) superior al 36% evaluado mediante monitorización continua de glucosa (MCG) en un grupo de pacientes con diabetes mellitus. Métodos: Se evaluó una cohorte de pacientes con diabetes tipo 2 (T2D). Se evaluaron variables demográficas, HbA1c, tasa de filtración glomerular (TFG) y régimen de tratamiento. Se realizó un análisis bivariado, para evaluar la asociación entre la variable resultado (CV > 36%) y cada una de las variables independientes. Se construyó un modelo multivariado para evaluar las asociaciones después de controlar las variables de confusión. Resultados:Se analizaron los datos de MCG de 274 pacientes. CV> 36% estuvo presente en 56 pacientes (20,4%). En el análisis bivariado se incluyeron variables demográficas y clínicas, como tiempo desde el diagnóstico, antecedente de hipoglucemia, A1c, FG y tratamiento instaurado. En el análisis multivariante, FG 9% (OR 2,81; IC 1,05,7,51; p:0,04) y antecedentes de hipoglucemia (OR 2,09; IC 1,02, 4,32; p: 0,04) se asociaron con VHG. El tratamiento con iDPP4 (OR 0,39; IC 0,19, 0,82; p: 0,01) y AGLP1 (OR 0,08; IC 0,01, 0,68; p: 0,02) se asoció inversamente con la VG. Conclusión:Variables clínicas como FG 9% y antecedentes de hipoglucemia se asocian a un VG alto. Nuestros datos sugieren que el uso de tecnología y tratamientos capaces de reducir la variabilidad glucémica podría ser útil en esta población para reducir el riesgo de hipoglucemia y mejorar el control glucémico.Q3Background: High glycemic Variability (HGV) has become a stronger predictor of hypoglycemia. However, clinical factors associate with HGV still are unknown. Objective: To determine clinical variables that were associated with a coefficient of variation (CV) above 36% evaluated by continuous glucose monitoring (CGM) in a group of patients with diabetes mellitus. Methods: A cohort of patients with type 2 diabetes (T2D) was evaluated. Demographic variables, HbA1c, glomerular filtration rate (GFR) and treatment regimen were assessed. A bivariate analysis was performed, to evaluate the association between the outcome variable (CV> 36%) and each of the independent variables. A multivariate model was constructed to evaluate associations after controlling for confounding variables. Results: CGM data from 274 patients were analyzed. CV> 36% was present in 56 patients (20.4%). In the bivariate analysis, demographic and clinical variables were included, such as time since diagnosis, hypoglycemia history, A1c, GFR and treatment established. In the multivariate analysis, GFR 9% (OR 2.81; CI 1.05,7.51; p:0.04) and hypoglycemia history (OR 2.09; CI 1.02,4.32; p:0.04) were associated with HGV. Treatment with iDPP4 (OR 0.39; CI 0.19,0.82; p:0.01) and AGLP1 (OR 0.08; CI 0.01,0.68; p:0.02) was inversely associated with GV. Conclusion: Clinical variables such as GFR 9% and a history of hypoglycemia are associated with a high GV. Our data suggest that the use of technology and treatments able to reduce glycemic variability could be useful in this population to reduce the risk of hypoglycemia and to improve glycemic control.Revista Internacional - Indexad

elaboracion de papel vegetal que cumpla las normas tappi para el diseno e impresion a partir de la fibra de la cascara del platano verde

En la presente investigación se elaborará un manual para la elaboración de papel vegetal que cumpla las normas TAPPI para el diseño e impresión a partir de la fibra de la cascara del plátano verde ya que estas técnicas antiguas que inusualmente se usan para la elaboración de papel artesanal han funcionado bien debido a que ha sido destinado para impresión serigrafía o manual que no demanden mayor calidad ni parámetros técnicos de su constitución. Hay que tener en ceunta que la fabricación del papel a mano es una técnica que a pesar de tener miles de años de antigüedad no ha sido explotada adecuadamente y no se consigue papel de buena calidad que pueda reemplazar a los que usamos normalmente. Muchos artesanos hacen papel a mano sin una técnica científica que permita conocer las propiedades de las fibras a utilizar para elaborar papel para imprenta o impresoras comunes. En nuestro caso elaboraremos papel vegetal a partir de la fibra de la cascara del plátano verde que presente las mejores propiedades de formación física y óptica.</p

Growth kinetics and atomistic mechanisms of native oxidation of ZrSx_xSe2−x_{2-x} and MoS2_2 crystals

A thorough understanding of native oxides is essential for designing semiconductor devices. Here we report a study of the rate and mechanisms of spontaneous oxidation of bulk single crystals of ZrS$_x$Se$_{2-x}$ alloys and MoS$_2$. ZrS$_x$Se$_{2-x}$ alloys oxidize rapidly, and the oxidation rate increases with Se content. Oxidation of basal surfaces is initiated by favorable O$_2$ adsorption and proceeds by a mechanism of Zr-O bond switching, that collapses the van der Waals gaps, and is facilitated by progressive redox transitions of the chalcogen. The rate-limiting process is the formation and out-diffusion of SO$_2$. In contrast, MoS$_2$ basal surfaces are stable due to unfavorable oxygen adsorption. Our results provide insight and quantitative guidance for designing and processing semiconductor devices based on ZrS$_x$Se$_{2-x}$ and MoS$_2$, and identify the atomistic-scale mechanisms of bonding and phase transformations in layered materials with competing anions