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Ítem Corredores de conservación y herramientas de manejo del paisaje: estrategias para la generación de conectividad en mosaicos de paisaje(Ministerio de Ambiente y Desarrollo Sostenible, República de Colombia, 2012-01-01) Vargas, William GerardoEn las últimas décadas, los resultados delas investigaciones sobre conservación yproducción sostenible en paisajes ruraleshan resaltado la importancia del manejosostenible en el territorio colombiano (Galindo y Murgueitio 2003, Muriel& Kattan 2009, Vargas et al. 2009a) ,en especial en ecosistemas másintervenidos como los de la región andina.Ésta es una de las mejores opciones paralograr la conservación efectiva de unabuena proporción de la biodiversidadcolombianaÍtem 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 Activity of (2E)-3-(2, 3-dimetoxifenil)-1-(4-metilfenil) prop-2-en-1-ona in the presence of poli(maleic acid-co-2-vinyl-pyrrolidone) on a β-lactamase producing clinical isolate of Staphylococcus aureus(Universidad de Antioquia, 2012-01-01) Salamanca Mejía, Constaín HugoDue to the current problem of resistance to b-lactam antibiotics, it has become necessary, in search of a solution, to work with new molecules with pharmacological potential, and to use novel polymeric systems as matrices or pharmaceutical excipients. Objective: To evaluate the antibiotic activity of ampicillin combined with a synthetic chalcone-type compound, the (2E)-3-(2,3-dimethoxyphenyl)-1-(4- methylphenyl) prop-2-en-1-one, on a clinical isolate of penicillin-resistant Staphylococcus aureus in the presence of a water soluble polymer matrix known as poly(maleic acid-co-2-vinyl-pyrrolidone). Materials and methods: The synthetic compound and the polymeric matrix were obtained by previously described methods. Tests for antibiotic activity against the strain of penicillin-resistant Staphylococcus aureus were done by the broth dilution technique which provided the minimal inhibitory concentrations of the compounds tested. Results: The chalcone-ampicillin mix shows lesser antibiotic effect than the ampicillin-sulbactam used as referent. However, when such mix is combined with the polymer matrix, antibiotic activity significantly increases as evidenced by decrease in the minimal inhibitory concentration with respect to the ampicillin-sulbactam referent.Ítem Estudio del efecto de los sistemas poliméricos PAM-18 K2 y PAM-18 Na2 sobre los perfiles de disolución de comprimidos de ampicilina(Universidad Icesi, 2013-01-01) Pineda Camero, Diego; Salamanca Mejía, Constain Hugo; Asesor TesisThe present grade project is part of an investigation work with a bigger scope, which is focused in the research of the characterization of physicochemical properties in aqueous solutions of polymer materials with amphiphilic characteristics, with the purpose to evaluate their potential as novel pharmaceutical matrices capable to decrease the biodegradability of betalactamic drugs. Specifically, in this grade project, the variation in dissolution profiles of commercial tablets of the betalactamic drug ampicillin in its trihydrate form was evaluated, in presence of the polymer materials PAM-18Na2, PAM-18 K2 and Eudragit E-100 Chloride in media with physiologic conditions of pH and ionic strength modified by action from the polymeric systems in dispersion, with pH values of 1,2 and 7,4 and ionic strength of 0,15 M in a temperature of 37°C.Ítem Estudios viscosimétricos para evaluar el fenómeno de asociación entre el EUDRAGIT e-100® modificado y la carbamazepina en medio acuoso.(Universidad Icesi, 2014-01-01) Barrera Contreras, Angélica EstefaniaThis project intended to assess the phenomenon of chemical association of the polymeric material, Hydrochloride Eudragit E-100, with a reference drug, as carbamazepine, using a methodology of capillary viscometry, previously standardized. A capillary viscometer known as Oswald or Ubbelohde viscometer, whose experimental measurement parameter is the flow time, or run-time was used. The run-time values have an indirect relationship with the relative viscosity, thereby allowing for differences between the relative viscosities of the polymer solutions Hydrochloride Eudragit E-100 in the presence and absence of drug. The determination of the run-time values were taken at 37 ° C, and pH values corresponding to 1.2, 2, 4, 6, 7.4, 8, and 10. We found that the standardized method showed a property repeatability and intermediate precision. Also, an effect of concentration and ionic strength of the medium in the relative viscosities of the ionomer solutions was obtained. And, a conformational transition phenomenon of Hydrochloride Eudragit E-100 in function of the pH of the medium was checked. This made possible to obtain a marked effect on the rheological behavior of the polymer solutions in the presence and absence of carbamazepine, thereby assuming a potential phenomenon of polymer-drug association. Moreover, we obtained that carbamazepine or model drug does not affect the viscosity of the aqueous media.Ítem Evaluación de la diversidad de arañas como indicadoras de la efectividad de las estrategias de restauración implementadas en el corredor biologico Barbas - Bremen, Filandia (Quindío-Colombia)(Universidad Icesi, 2014-01-01) Ortiz Movliav, Carolina; Vargas, William Gerardo; Asesor TesisSpiders are a diverse and abundant group in all terrestrial ecosystems. Their communities are influenced by the type of habitat, land use, and plant architecture, so they are well accepted in ecological and environmental studies. They are generalist predators that have a major impact on the regulation of herbivore populations, also they are easy to collect and identify. The objective of this research was to evaluate the effectiveness of restoration strategies implemented in biological corridors connecting the Barbas River Canyon and The Forest Preserve of Bremen (Filandia-Quindío), through the measure of the diversity of spiders. For this, samples were taken in three biological corridors “Los Monos”, “Las Pavas” and “Los Colibríes”, in two forest fragments, Barbas and Bremen and in a paddock near to the corridors. Sampling was conducted during day sessions, and during dry and rainy seasons over one year period, using three methods: hand collecting (Looking up and looking down), sweeping with entomological net and using a beating trap. After 96 sampling unites, 736 individual were identified grouped into 18 families and 126 morphospecies.Ítem Evaluación del biocarbón derivado de cascarilla de arroz como potenciador del establecimiento y proliferación de bacterias en suelos no perturbados(Universidad Icesi, 2014-01-01) Belalcázar Serrano, Stefanía; Ghneim Herrera, Thaura; Asesor TesisLa producción y aplicación de biomasa pirolizada (biocarbón) al suelo, ha sido una herramienta utilizada para el almacenamiento de carbono en ecosistemas terrestres (Khodadad et al., 2011). El biocarbón puede incrementar la fertilidad del suelo mientras reduce el uso de agua y de fertilizantes químicos. El aumento en la fertilidad del suelo está relacionado con la capacidad del biocarbón para absorber e intercambiar nutrientes y materia orgánica, pero también con su efecto positivo sobre la abundancia y diversidad de microorganismos (Khodadad et al., 2011). El procesamiento industrial del arroz genera, como material de desecho, toneladas de cascarilla de arroz. Tradicionalmente, la cascarilla se ha empleado en la producción de alimentos animales y como componente de mezclas de suelo utilizadas en jardineria. Recientemente ha surgido interés en explotarla como materia prima para la producción de biocarbón, para ello se debe evaluar su potencial para generar los efectos benéficos observados con otros tipos de biocarbones.Ítem Simulación computacional del bloqueo del canal de potasio KV1.3 por toxinas del veneno de escorpión(Universidad Icesi, 2014-01-01) Velásquez García , Natalia; Arango Mambuscay, Carlos Alberto; Asesor Tesis; Asesor TesisExiste una gran variedad de canales de potasio, los cuales se encargan de mediar el trasporte de los iones K+ a través de la membrana celular. Además cumplen múltiples funciones en la producción y generación de potenciales de acción, proliferación celular y apoptosis. Se seleccionó Kv1.3 como objeto de estudio de éste proyecto, debido a que, este canal se encuentra en la membrana plasmática y mitocondrial de los linfocitos T, y están estrechamente relacionados con el sistema inmune