150 research outputs found

    Calcium alginate beads reinforced with synthetic oligomers, linear polyethylenimine and Cu(II): structural stability and potential applications

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    Calcium alginate beads were reinforced with linear polyethylenimine (PEI), Cu(II) and synthetic oligomers derived from a diepoxide, methacrylic acid and imidazole, to increase the resistance to stirring and vibration for environmental applications. The FT-IR and Raman spectra of the beads confirmed the presence of the organic reactants and their interactions. The SEM images of the lyophilized beads with an excess of oligomers exhibited an ordered core structure surrounded by a shell. The elemental mapping by EDAX showed a homogeneous distribution of Ca(II) and Cu(II), and a density influenced by PEI. The beads more resistant to sonication were those with the highest oligomer content. The enzyme soybean peroxidase (SBP) was immobilized in the beads for an environmental application that requires a stable matrix from chemical and structural points of view. The synergistic action of the entrapped SBP and Cu(II) on H2O2 activation induced the removal of an azo dye from aqueous solutions. Free radicals and O2 were released from Cu(II)-sites in the presence of the peroxide. The content of the oligomers determined the efficiency of the beads on dye removal.Fil: Torres, Dimas Ignacio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Villanueva, María Emilia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Lazaro Martinez, Juan Manuel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Copello, Guillermo Javier. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Campodallorto, Viviana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentin

    Propuesta de capacitación de personal para mejorar la calidad de servicio del restaurante Sumaq, Chiclayo, 2016

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    La actual búsqueda tuvo como objetivo general proponer un plan de capacitación de personal para mejorar la calidad de servicio del restaurante Sumaq. Se perpetró una investigación de tipo descriptivo – propositiva la cual permite estar al tanto de la problemática que muestra la empresa en cuanto a la calidad de servicio que brinda los colaboradores en el restaurante Sumaq. La técnica utilizada fue la encuesta con su instrumento cuestionario hecho con 20 ítems operados de acuerdo a las dimensiones de las variables capacitación laboral y calidad de servicio, el cual se utilizó para la obtención de información. Los cuestionarios estuvieron fiables a través de la prueba de alfa de cronbach. Este instrumento fue aplicado a la muestra de 11 colaboradores que laboran en el restaurante Sumaq y a una muestra de 366 clientes del restaurante Sumaq. El nivel de calidad de servicio del restaurante Sumaq, es medio, el promedio de esta variable es 3.6, con este indicador se concluye que la calidad de servicio es la adecuada para el 80% de la población de los clientes. La calidad de servicio se caracteriza por tener una brecha de insatisfacción en las dimensiones de fiabilidad y empatía, los clientes encuentran insatisfacción la publicidad ofrecida por el restaurant y por las habilidades de atención de los clientes.Tesi

    Velocidad media de infiltración en un vertisol bajo distintos sistemas de labranza

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    Soil compaction is regarded as the most serious environmental problem caused by conventional agriculture. Few studies are concerned with the assessment of soil compaction using infiltration speed, specifically in the Vertisol soil characteristic of the main maize producing area of the Toluca-Atlacomulco Valley in central Mexico. The aim of this research was to examine the effect on infiltration speed and penetration resistance of a Vertisol soil when compacted by wheeled agricultural traffic in three different types of tillage systems: zero, minimal and conventional. Penetration resistance was measured on the wheel track with a portable digital penetrometer, and the mean infiltration speed was determined according to the double cylinder infiltrometer method. The pressure exerted by the number of wheeled traffic passes increased Vertisol soil compaction at 30 cm depth. Even though the benefits of zero tillage were similar to those showed by mínimum tillage during the experimental period, minimum tillage reported the highest infiltration spee

    pH and ion-selective swelling behaviour of keratin and keratose 3D hydrogels

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    The oxidation of keratin hydrogels was optimized aiming to obtain keratose hydrogels while maintaining the original 3D structure and pH-responsive behaviour. In addition, we present a comparative study of their dual-stimuli responsive behaviour regarding the pH-responsiveness and their previously non-described ion selective responsiveness. Keratose and keratin hydrogels showed similar swellings when contracted at low pH, and the former showed steeper expansion and higher swelling than the latter at high pH. In addition, both hydrogels showed selective responsiveness toward Ca2+ ions when expanded, and toward Cu2+ ions when contracted. IR, Raman, ss-NMR, HRMAS NMR, SAXS, and thermal characterization demonstrated that oxidation does not interfere with the stimuli-responsive mechanisms related to protein conformation. The higher swelling of keratose hydrogels would be originated in the increase of the mobility of the chains after oxidation coupled to the hydration of sulfonic acid groups.Fil: Galaburri, Gonzalo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Peralta Ramos, María Luz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica Instrumental; ArgentinaFil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Fernández de Luis, Roberto. No especifíca;Fil: Arriortua, María Isabel. Universidad del País Vasco; EspañaFil: Villanueva, María Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Copello, Guillermo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentin

    Pyronaridine exerts potent cytotoxicity on human breast and hematological cancer cells through induction of apoptosis

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    The potent antimalarial drug pyronaridine (PND) was tested for its potential as an anticancer drug. After exposing cancerous (17) and non-cancerous (2) cells to PND for 72 hr, PND was found to exhibit consistent and potent cytotoxic activity at low micromolar (μM) concentrations that ranged from 1.6 μM to 9.4 μM. Moreover, PND exerted a significant selective cytotoxicity index (SCI) on five out of seven breast cancer cell lines tested, with favorable values of 2.5 to 4.4, as compared with the non-cancerous breast MCF-10A cell line. By using the same comparison, PND exhibited a significant SCI on three out of four leukemia/lymphoma cell lines with promising values of 3.3 to 3.5. One breast cancer and one leukemia cell line were tested further in order to determine the likely mode of action of PND. PND was found to consistently elicit phosphatidylserine externalization, mitochondrial depolarization, and DNA fragmentation, in both the triple negative MDA-MB-231 breast cancer and HL-60 leukemia cell lines. In addition, PND treatment altered cell cycle progression in both cancer cells. Subsequent DNA mobility-shift assays, UV-Visible spectroscopic titrations, and circular dichroism (CD) experiments revealed that PND intercalates with DNA. The findings presented in this study indicates that PND induces apoptosis and interfered with cell cycle progression of cancer cell lines and these results indicate that this drug has the potential as a repurposed drug for cancer therapy

    Acute Coronary Syndrome in the Older Patient

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    Coronary artery disease is one of the leading causes of morbidity and mortality, and its prevalence increases with age. The growing number of older patients and their differential characteristics make its management a challenge in clinical practice. The aim of this review is to summarize the state-of-the-art in diagnosis and treatment of acute coronary syndromes in this subgroup of patients. This comprises peculiarities of ST-segment elevation myocardial infarction (STEMI) management, updated evidence of non-STEMI therapeutic strategies, individualization of antiplatelet treatment (weighting ischemic and hemorrhagic risks), as well as assessment of geriatric conditions and ethical issues in decision making

    3-Hydroxykynurenic acid: Physicochemical properties and fluorescence labeling

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    Quinoline is one of the most important heterocyclic systems in life sciences. Some derivatives are normal metabolites, and others are used as antibacterial, antimalarial, and anticancer agents. In this work, we describe the synthesis, physicochemical properties, and fluorescence features of a new 4-quinolinone fluorophore, 3-hydroxykynurenic acid (3-HOKA). 3-HOKA was obtained by alkoxide-induced rearrangement of ethyl isatinacetate followed by acidification and then alkaline hydrolysis. The fluorescent compound was characterized by NMR, MS, IR, and UV–Vis spectra. 3-HOKA can exist under a keto-enol equilibrium, but the 4-quinolinone form is the predominant tautomer. In PBS (pH = 7.4), the anionic keto form of 3-HOKA showed a maximum absorption at 368 nm, a fluorescence peak at 474 nm, and a fluorescence quantum yield (ΦF): 0.73. 3-HOKA is photostable and is a moderately weak oxygen generator. Viability assays on HeLa cells indicated that 3-HOKA did not induce significative cytotoxic effects. Under UV excitation, a bright blue fluorescence was selectively found in a singular body within the cytoplasm, a labeling pattern that suggests the possible localization of the probe in the centriole or related structures. Therefore, this novel fluorophore represents a promising prototype compound owing to its biocompatibility and potential biological applications.Fil: Shmidt, María Sol. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Garcia Vior, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Ezquerra Riega, Sergio Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Abasolo, María I.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Lazaro Carrillo, Ana. Universidad Autónoma de Madrid; EspañaFil: Tabero, Andrea. Universidad Autónoma de Madrid; EspañaFil: Villanueva, Angeles. Universidad Autónoma de Madrid; España. Instituto Madrileño de Estudios Avanzados en Nanociencia; EspañaFil: Moglioni, Albertina Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: del Blanco, María Mercedes. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; ArgentinaFil: Stockert Cossu, Juan Carlos. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Instituto de Investigacion y Tecnología en Reproducción Animal; Argentin

    Circulating Tumor Cells Enumeration from the Portal Vein for Risk Stratification in Early Pancreatic Cancer Patients

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    [Simple Summary] Effective biomarkers are needed to enable personalized medicine for pancreatic cancer patients. This study analyzes the prognostic value, in early pancreatic cancer, of circulating tumor cells and clusters from the central venous catheter and portal blood. Circulating tumor cells were isolated using an immunomagnetic selection and were detected by microscopy using immunocytochemistry staining. In conclusion, the circulating tumor cell number in portal blood identifies a death risk in patients with early pancreatic cancer.[Abstract] Background. Effective biomarkers are needed to enable personalized medicine for pancreatic cancer patients. This study analyzes the prognostic value, in early pancreatic cancer, of single circulating tumor cell (CTC) and CTC clusters from the central venous catheter (CVC) and portal blood (PV). Methods. In total, 7 mL of PV and CVC blood from 35 patients with early pancreatic cancer were analyzed. CTC were isolated using a positive immunomagnetic selection. The detection and identification of CTC were performed by immunocytochemistry (ICC) and were analyzed by Epi-fluorescence and confocal microscopy. Results. CTC and the clusters were detected both in PV and CVC. In both samples, the CTC number per cluster was higher in patients with grade three or poorly differentiated tumors (G3) than in patients with well (G1) or moderately (G2) differentiated. Patients with fewer than 185 CTC in PV exhibited a longer OS than patients with more than 185 CTC (24.5 vs. 10.0 months; p = 0.018). Similarly, patients with fewer than 15 clusters in PV showed a longer OS than patients with more than 15 clusters (19 vs. 10 months; p = 0.004). These significant correlations were not observed in CVC analyses. Conclusions. CTC presence in PV could be an important prognostic factor to predict poor prognosis in early pancreatic cancer. In addition, the number of clustered-CTC correlate to a tumor negative differentiation degree and, therefore, could be used as a diagnostic biomarker for pancreatic cancer.This research was funded by Carlos III Health Institute (Health Research Fund) grant number PI16/01465 and PI19/01821 (Co-financed by the European Regional Development Fund “A way to make Europe”)
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