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Ítem Amyloid-beta immunotherapy: the hope for Alzheimer disease?(Universidad del Valle, 2016-10-01) Lopera, FranciscoAlzheimer disease (AD) is the most prevalent form of dementia of adult-onset, characterized by progressive impairment in cognition and memory. There is no cure for the disease and the current treatments are only symptomatic. Drug discovery is an expensive and time-consuming process; in the last decade no new drugs have been found for AD despite the efforts of the scientific community and pharmaceutical companies. The Aβ immunotherapy is one of the most promising approaches to modify the course of AD. This therapeutic strategy uses synthetic peptides or monoclonal antibodies (mAb) to decrease the Aβ load in the brain and slow the progression of the disease. Therefore, this article will discuss the main aspects of AD neuropathogenesis, the classical pharmacologic treatment, as well as the active and passive immunization describing drug prototypes evaluated in different clinical trials.Ítem Costo-efectividad de toracotomía v videotoracoscopia en pacientes con cáncer de ersus pulmón(2015-03-13) Guevara Cuéllar, César AugustoLos pacientes con cáncer de pulmón de célula no pequeña en estadio I, pueden someterse a videotoracoscopia o toracotomía. El objetivo de este estudio fue determinar la razón costo-efectividad de estas dos alternativas.Ítem Freeze-drying: Perceptions and challenges for drying foodstuffs and plant extracts(Universidad de Antioquia, 2015-01-01) Salamanca Mejia, Constain HugoOne of the most important features of foodstuffs and plant extract-based products is related to their fragile stability, especially when exposed to several ambient factors such as air, light radiation, heat and water vapour. The latter may contribute to the increase of free or bound water associated to the product. In this scenario, these variables may lead to different phenomena such as self-oxidation and hydrolysis of functional compounds and thus, a considerable inconsistency of products where these substances are part of occurs. On the other hand, these factors affect more drastically the product stability, especially when they possess a high intrinsic surface area and thus, are more likely to absorb a significant amount of water. Furthermore, in liquid products oxidation, hydrolysis and precipitation problems are more probable to happen
Ítem Aggregates of alternate amphiphilc polyanion to carry zwitterionic drug in aquedous media(2015-06-01) Quintero, AndrésThe effect of amphiphilic polyanion Poly(maleic acid-alt-octadecene)sodium salt on solubility of a zwitterionic drug (ampicillin trihydrate) in aqueous media was evaluated. This polymeric salt was obtained by an equimolar reaction of parent copolymer poly Poly(maleic acid-alt-octadecene)with an aqueous solution of NaOH. The obtained amphiphilic polyanion was purified by dialysis and lyophilization and was characterized by FTIR spectroscopy. Secondly, a method for the model drug quantification by UV spectrophotometry at 37°C was standardized. Also the grade of association drug-polymer in aqueous media using ultrafiltration methodology at three levels of temperature (20, 30 and 40°C) and two levels of pH (1.2 and 7.4) was determined. Finally, the variation of aqueous solubility of ampicillin trihydrate in ultra-pure water and two buffer media with pH of 1.2 and 7.4 with an ionic strength of 0.15 M at 37°C in presence and absence of amphiphilic polyanion was evaluated. It was found that maximum solubility is reached at a pH value of 1.2 in absence of polymeric material with a value of 36 mg/mL, which diminishes dramatically to a value of 8.3mg/mL when the polyanion is added. In the other side, when the system has a pH value of 7.4, the drug solubility slightly increases from 13 to 16mg/mL in presence of polymeric material, describing that solubility of this kind of drugs is strongly influenced by aqueous media and this type of polymeric materials.Ítem Do thermoregulatory costs limit altitude distributions of Andean forest birds?(Blackwell Publishing Ltd, 2017-01-01) Robinson, Scott K.Along tropical mountains, species often occupy narrow altitude ranges. Numerous biotic and abiotic factors have been proposed as determinants of altitude occupancy. We measured several aspects of thermal physiology of 215 bird species across a 2·6-km altitude gradient in the Peruvian Andes. We predicted that highland species would show adaptation to the colder high-altitude climate and that energy costs of thermoregulation might limit upslope dispersal of lowland natives. We found reductions in thermal conductance, body temperature and lower critical temperature in highland birds compared with lowland species. These combine to make highland natives more resistant to heat loss. We did not find convincing evidence that acute thermal limits or energy costs of thermoregulation constrained altitude distributions.Ítem Cost-Effectiveness of the Quantification of Enzymatic Activity in Leukocytes in Comparison to Its Nonrealization for a Rare Disease in Latin America: The Case of Mucopolysaccharidosis Type II in Colombia(Elsevier Inc., 2016-12-01) Parody Rua, ElizabethBackground: Mucopolysaccharidosis (MPS) type II is produced by a deficiency of iduronate-2-sulfatase (I2S). The quantification of the enzyme activity in leukocytes is used as diagnostic confirmation of MPS. Objective: To determinate the cost-effectiveness of the measurement of I2S enzyme activity in leukocytes compared with not carrying out the enzyme activity measurement for diagnostic confirmation of MPS II from the perspective of the Colombian health system. Methods: A cost-effectiveness analysis was conducted on the basis of a decision tree model. The measure of effectiveness was the correct diagnosis of cases of MPS II. The costs of I2S enzymatic quantification in leukocytes, consultation with a geneticist and with other specialists, and costs of diagnostic procedures were included. The time horizon was less than 1 year. A probabilistic sensitivity analysis was performed using Monte-Carlo simulation with 10,000 iterations. Results: The incremental cost was -US $43,145 with an incremental effectiveness of 42 cases. The probabilistic sensitivity analysis confirms the results of basal data, in which the quantification of I2S enzyme activity was less costly and more effective than the alternative. Conclusions: The quantification of I2S enzymatic activity is a dominant technology for the diagnostic confirmation of MPS II, compared with not making the quantification, from the perspective of the Colombian health system. © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR).Ítem Simulación de la dinámica de polímeros anfifílicos y su potencial aplicación para encapsular moléculas de fármacos(Universidad Icesi, 2012-08-29) Arango Mambuscay, Carlos Alberto[No contiene resumen]Ítem Síntesis de polietileno con ramificaciones muy largas y poco frecuentes(Sena, 2015-12-03) Delgado, Lina M.Este proyecto se realizó por medio de una polimerización vía “acyclic diene metathesis polymerization (ADMET)” en presencia del catalizador de Grubbs de primera generación con el fin de sintetizar polietileno (PE) lineal de baja densidad (LLDPE), el cual a diferencia del LLDPE comercial presenta ramificaciones en lugares específicos de la cadena carbonada. En este proyecto se obtuvieron tres materiales, dos de ellos con ramificaciones de 17 y 21 carbonos las cuales aparecen cada 21 carbonos, mientras el tercero de ellos se sintetizó con una ramificación de 21 carbonos la cual aparece cada 39 carbonos.Ítem Residuos agroindustriales y bioeconom en el Valle del Cauca. Fuentes renovables de biomateriales a partir de subproductos de la industria azucarera(Universidad de Cartagena, 2014-05-21) XII Congreso Colombiano de Fitoquímica; Montoya Peláez, Guillermo LeónEs evidente que nuestro pa tiene vocaci agrola y actualmente el gobierno nacional tiene priorizadas ciertas cadenas productivas entre las cuales se encuentra la ca de azar focalizada en m de 200 mil hecteas sembradas principalmente en el Valle del Cauca. La bioeconom por otro lado es un concepto relativamente reciente que visualiza el procesamiento sustentable de la biomasa para obtener biocombustibles, energ tmica, compuestos quicos y materiales con distintos fines productivos. Aplicando el concepto de bioeconom y considerando las cifras de residuos producidos por el sector azucarero colombiano (genera alrededor de 50 mil toneladas de residuos/d), proponemos el diagntico de un metabolito secundario desperdiciado a lo largo de su paso por el proceso de producci de azar y la fabricaci de biomateriales a partir de esta fuente renovable. En el desarrollo de este proyecto de investigaci se validun modo moderno de anisis (SPE-UPLC-ELSD) para valorar 7 etapas del proceso de extracci de azar de un ingenio azucarero. Esta evaluaci permitidefinir los puntos m probables de recuperaci sin interferir con el proceso de producci de la empresa en donde se realizel diagntico. Adicionalmente se estableciun mecanismo de reacci para la generaci de un biopolero hiper-ramificado a partir de este residuo. Estos resultados demuestran la factibilidad de aplicar conceptos de bioeconom en los sectores agrolas m promisorios del territorio nacional y generar nuevas fuentes de crecimiento econico de cara a la apertura comercial en la cual Colombia se encuentra sumergida.Ítem Synthesis, Characterization And Application In Controlled Drug Release Of Chitosan Hydrogels Obtained From Aspergillus Niger.(European Polymer Federation, 2011-06-26) XII Congress of the Specialized Group of PolymersNora Elena Valderruten Posso, PhD Universidad del país Vasco, 2001. En Ciencias Químicas, Maestría Universidad del Valle, Posgrado Universidad del Valle en Biología Química, profesora de tiempo completo de la Universidad Icesi del Departamento Académico Ciencias Químicas de la Facultad de Ciencias Naturales y miembro del comité asesor, - trabajps dirigidos/tutorias- trabajos de grado de pregrado, jurado de comité evaluación- miembro del consejo de la Facultad de Ciencias Naturales y coordinadora de cursos de Química Orgánica. Sus trabajos de investigación y desarrollo en la obtención de polimeros biodegradables apartir de ácido grasos de origen vegetal, obtención de materiales compuestos Core-Shell mediante inmovilizacion de catalizadores metalogénicos, obtención de materias polimetricos inteligentes a partir de un subproducto industrial con potencial en la industria farmacéuticas y otras. Synthesis, Characterization And Application In Controlled Drug Release Of Chitosan Hydrogels Obtained From Aspergillus Niger.