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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 Synanthropic Cockroaches (Blattidae: Periplaneta spp.) Harbor Pathogenic Leptospira in Colombia(Entomological Society of America, 2016-06-01) Bonilla, ÁlvaroLeptospirosis cases in Colombia are typically linked to peridomestic rodents; however, empirical data suggest that Leptospira-infected patients with no apparent exposure to these reservoirs are common. Cockroaches (Periplaneta spp.) have equal or greater interaction with humans than rodents, yet their potential role as carriers of Leptospira has not been assessed. We determined if pathogenic Leptospira is harbored by Periplaneta spp. in Cali (Colombia) and the variables influencing this relationship. Fifty-nine cockroaches were captured from seven sites and DNA was extracted from the body surface and digestive tract for a multiplex polymerase chain reaction, targeting genes secY and flaB. Logistic regression models and proportion tests showed a higher likelihood for Leptospira to be isolated from body surfaces (P>0.001) and from individuals inside houses (six times more likely). These findings are the first to demonstrate an association between Periplaneta spp. and Leptospira, suggesting the need to investigate the potential for cockroaches to serve as reservoirs or transport hosts for Leptospira.Ítem Spatial modeling of cutaneous leishmaniasis in the Andean region of Colombia(Fundaco Oswaldo Cruz, 2016-07-01) Pérez-Flórez, MauricioThe objective of this research was to identify environmental risk factors for cutaneous leishmaniasis (CL) in Colombia and map high-risk municipalities. The study area was the Colombian Andean region, comprising 715 rural and urban municipalities. We used 10 years of CL surveillance: 2000-2009. We used spatial-temporal analysis - conditional autoregressive Poisson random effects modelling - in a Bayesian framework to model the dependence of municipality-level incidence on land use, climate, elevation and population density. Bivariable spatial analysis identified rainforests, forests and secondary vegetation, temperature, and annual precipitation as positively associated with CL incidence. By contrast, livestock agroecosystems and temperature seasonality were negatively associated. Multivariable analysis identified land use - rainforests and agro-livestock - and climate - temperature, rainfall and temperature seasonality - as best predictors of CL. We conclude that climate and land use can be used to identify areas at high risk of CL and that this approach is potentially applicable elsewhere in Latin America.Ítem Tunable polyesterification of xylitol: from linear to crosslinked structures(John Wiley and Sons Ltd, 2017-04-01) Benitez, RicardoThe copolymerization by condensation chemistry of succinic acid and xylitol, a byproduct from the sugarcane and alcohol industry, is reported. Two methodologies were studied concerning succinic acid, with and without carboxylic acid activation, yielding crosslinked and linear low molecular weight polymers, respectively. All polymerizations were carried out at reaction times in the range from 36 to 80 h, with a molar mass ratio of 1:1 and 1:3. Linear and crosslinked polyesters were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, DSC and TGA, and structural characterization was carried out by Fourier transform infrared spectroscopy and NMR. © 2016 Society of Chemical Industry. © 2016 Society of Chemical IndustryÍtem 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 happenÍtem 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 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.