23 research outputs found

    Quantic Analysis of Formation of a Biomaterial of Latex, Retinol, and Chitosan for Biomedical Applications

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    The present work shows the quantum theoretical analysis and practical tests for the formation of a homogeneous mixture with Latex (Lx), Chitosan (Qn) and Retinol (Rl), which work as possible biomaterial for regeneration of epithelial tissue. Lx, Qn, and Rl compounds molecules were designed through Hyperchem to get the coefficient of electrostatic potential calculations. The amounts used to create the biomaterial are minimum depending on the quantities of molecules used in chemical design. A positive calculation was obtained for the reaction of these three compounds and the formation of the biomaterial in physical checking theory etc

    Quantic Analysis of the Adherence of a Gram-Negative Bacteria in A HEPA Filter

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    It is known that Gram-negative bacteria (GNB) are the most frequent bacteria in hospital units. It is also known that GNBs generate a greater number of nosocomial infections in critical areas. In the present work, the adhesion of the bacterial cell wall (BCW) to the compounds of the material layers of a high efficiency filter (HEPA) was analyzed. The analysis was carried out by means of molecular simulation and quantum chemistry. The BCW and HEPA molecules were designed using Hyperchem software for simulation. The calculations of the quantum interactions of the molecules were carried out using the theory of the electron transfer coefficient (ETC). It obtained from 4 to 6 compounds that are more likely to interact even as a chemical reaction. The compounds of the glass fibers are the ones that work best for the adhesion and destruction of the BCW

    Morphological and Rheological Characterization of Gold Nanoparticles Synthesized Using Pluronic P103 as Soft Template

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    The synthesis of gold nanoparticles (Au-NPs), using Pluronic® P103 as soft template to design tuned hybrid gold/P103 nanomaterials, is reported here. The effect of the concentration of P103 and the synthesis temperature on the growth, size, and morphology of Au-NPs were studied. The rheological properties of these hybrid nanomaterials at different measured temperatures were studied as well. By increasing the concentration of P103, the micelles progressively grew due to an increase in the number of surface cavities. These cavities came together causing large nucleation centers and developing larger Au-NPs. The synthesis temperature was varied to induce significant dehydration of the P103 micelles. Below the cloud point temperature micelles underwent distinct changes related to spherical-to-polymer-like micelles transitions. Two nanostructures were formed: (1) small Au-NPs arranged on the surface of micelles, which acted as soft templates, and (2) large and independent Au-NPs. Above the cloud point temperature, Au-NPs were related to the shape and size of the P103 micellar aggregates. Rheological measurements showed that viscosity was sensitive to the concentration of P103. Also, it was demonstrated that synthesis temperature had a considerable influence on viscosity of the produced nanomaterials

    Body composition by dual X-ray absorptiometry in Mexican schoolchildren with or without obesity

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    Objective: Apply dual X-ray absorptiometry (DXA) to determine the amount of fat mass, lean mass, and bone mineral density in Mexican schoolchildren with and without obesity. Material and methods: We performed an observational, analytical, comparative, cross-sectional study of 80 Mexican schoolchildren who attended the Nutrition Clinic of the Pediatric Medical Center in Monterrey, Mexico during the period of January to April 2005. Body mass index (BMI) was determined to classify the participants according to the growth charts of the Centers for Disease Control and Prevention. Two groups of 40 children each (with and without obesity) were formed and DXA was carried out on each individual. Cronbach’s Alpha was used to determine instrument reliability and the Kolmogorov-Smirnov test was used to test the normality of numerical variables. Means were compared using Student´s t test. Results: Statistically signiicant differences were found in fat mass (p≤0.001) and lean mass (p≤0.001), but not in bone mineral content (p=0.051) between both groups. Conclusions: Differences exist in fat mass and lean mass in both groups, but not in bone mineral content between both groups. A signiicant positive correlation was found between fat mass, determined by DXA, and BMI in schoolchildren with and without obesit

    CAPN3, DCT, MLANA and TYRP1 are overexpressed in skin of vitiligo vulgaris Mexican patients

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    Abstract. Vitiligo is a disorder causing skin depigmentation, in which several factors have been proposed for its pathogenesis: Environmental, genetic and biological aspects of melanocytes, even those of the surrounding keratinocytes. However, the lack of understanding of the mechanisms has complicated the task of predicting the development and progression. The present study used microarray analysis to characterize the transcriptional profile of skin from Vitiligo Vulgaris (VV) patients and the identified transcripts were validated using targeted high-throughput RNA sequencing in a broader set of patients. For microarrays, mRNA was taken from 20 skin biopsies of 10 patients with VV (pigmented and depigmented skin biopsy of each), and 5 biopsies of healthy subjects matched for age and sex were used as a control. A signature was identified that contains the expression pattern of 722 genes between depigmented vitiligo skin vs. healthy control, 1,108 between the pigmented skin of vitiligo vs. healthy controls and 1,927 between pigmented skin, depigmented vitiligo and healthy controls (P<0.05; false discovery rate, <0.1). When comparing the pigmented and depigmented skin of patients with vitiligo, which reflects the real difference between both skin types, 5 differentially expressed genes were identified and further validated in 45 additional VV patients by RNA sequencing. This analysis showed significantly higher RNA levels of calpain-3, dopachrome tautomerase, melan-A and tyrosinase-related protein-1 genes. The data revealed that the pigmented skin of vitiligo is already affected at the level of gene expression and that the main differences between pigmented and non-pigmented skin are explained by the expression of genes associated with pigment metabolism

    Ética profesional en educación superior : finalidades, estrategias y desafíos de la formación

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    Todo proyecto educativo que no responde a su época se expone a problemas de legitimidad y al duro escrutinio y sanción de los usuarios. Las instituciones de educación superior no son la excepción de esta premisa clásica, incluso más validada por eldinamismos, la versatilidad y ojo crítico en el mundo contemporáneo. La ética se ha convertido en el baremo principal para someter a juicio a las instituciones y a las personas que ahí actuan, como a las finalidades que se pretenden en sus acciones. En esta perspectiva, debe examinarse la función de las instituciones de educación superior.Este libro es el esfuerzo colectivo por acercarnos a esa problemática, en especial a las finalidades, estrategias y relaciones en juego para cumplir la tarea de la formación y sus nexos inevitables con la ética profesional

    Reciclado de aceites vegetales

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    Nota informativa sobe las malas prácticas en el deshecho de aceites, así como su proceso de recuperación y reciclado para otros uso

    Synthesis and characterization of AN/EGDMA-based adsorbents for phenol adsorption

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    "In this work, acrylonitrile (AN)/ethylene glycol dimethacrylate (EGDMA) cross-linked polymeric adsorbents were synthesized by the suspension polymerization method. The adsorbents were prepared varying the EGDMA cross-linker ratio from 100 to 60%. It was found that the swelling factor and the specific surface area changed inversely with the crosslinking degree. In addition, the thermal characterization indicated that polymers stability increased as the crosslinking degree decreased. The polymers were tested as phenol adsorbents and it was found that the higher uptake level was reached when the acrylonitrile concentration increased in the polymer. Adsorption isotherm was determined fitting the Langmuir model, indicating a homogeneous surface of the adsorbents. Moreover, the kinetic studies indicated that the rate controlling step corresponded to the intraparticle diffusion since adsorption is promoted when the adsorbent is swollen"

    Phenolic resin-commercial graphite disk preparation: Effect of the resin amount and the thermal treatment on the structural, morphological and mechanical properties

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    "In this work, macroporous discs were prepared using synthesized phenolic resin (PR) and commercial graphite mixtures (15–40 weight percent). The structure of the PR resin was confirmed by Proton Nuclear Magnetic Resonance and Gas Chromatography Coupled to Mass Spectrometry while the curing temperature was determined by Fourier Transform Infrared Spectroscopy. Also, the surface homogeneity and the structural analysis of the prepared disks were examined by means of scanning electron microscopy and X-ray powder diffraction analysis, respectively. According to the micrographs it was observed that as the PR amount increased disks’ porosity decreased giving rise to homogeneous and smooth surfaces which was explained in terms of the X-ray diffraction analysis that proved that graphite average crystal size (ACS) values decreased progressively with PR amount. Furthermore, it was demonstrated that the mechanical resistance could be tuned with the PR amount and the thermal treatment since as both increased the disks’ hardness augmented"
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