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Guadalajara, Mexico

Rodriguez A.,University of Guadalajara | Casillas N.,University of Guadalajara | Sainz A.,University of Guadalajara | Gomez S.,University of Guadalajara | And 3 more authors.
ECS Transactions | Year: 2011

The construction and application of a monopolar, packed bed, parallel plate electrochemical flow reactor for removal of Cu+2 ions from "ordinary" (i.e., product of the first distillation of tequila) is presented. The reactor is constructed by nylomaq frameworks to accommodate copper hanks cathodes, separated from graphite anodes by means of polypropylene (Celgard®) membranes. Results of the copper concentration profile in ordinary solutions and pH variation along the reactor are reported. Copper concentration continuously decreases along the reactor reaching a removal efficiency ranging from 82 to 85% for all the inlet concentrations examined. The experimental copper concentration profile fits an exponential decay along the axial reactor coordinate, in agreement with theory for porous flow reactors. An equation deduced from the material balance for a packed bed electrode (i.e., copper hanks), that takes into account a kinetic rate constant and mass transfer coefficient to predict the concentration vs. position along the reactor is also presented. ©The Electrochemical Society.

Gomez-Patino M.B.,National Polytechnic Institute of Mexico | Cassani J.,Metropolitan Autonomous University | Jaramillo-Flores M.E.,National Polytechnic Institute of Mexico | Zepeda-Vallejo L.G.,National Polytechnic Institute of Mexico | And 3 more authors.
Molecules | Year: 2013

The main monomer of tomato cuticle, 10,16-dihydroxyhexadecanoic acid (10,16-DHPA) and its methyl ester derivative (methyl-10,16- dihydroxyhexadecanote; methyl-10,16-DHHD), were used to study their oligomerization reactions catalyzed by five lipases: Candida antarctica lipase B (CAL-B), Rhizomucor miehei lipase (RM), Thermomyces lanuginosus lipase (TL), Pseudomonas cepacia lipase (PCL) and porcine pancreatic lipase (PPL). For 10,16-DHPA, optimum yields were obtained at 60 °C using toluene and 2-methyl-2-butanol (2M2B) as solvent, while for methyl-10,16-DHHD the bests yields were obtained in toluene and acetonitrile. Both reactions leaded to linear polyesters according to the NMR and FT-IR analysis, and there was no data indicating the presence of branched polymers. Using optimized conditions, poly(10,16-DHPA) and poly(methyl-10,16-DHHD) with Mw = 814 and Mn = 1,206 Da, and Mw = 982 and Mn = 860 Da, respectively, were formed according to their MALDI-TOF MS and ESI-MS data. The self-assembly of the polyesters obtained were analyzed by AFM. © 2013 by the authors; licensee MDPI, Basel, Switzerland.

Gutierrez Reyes J.A.,SENASICA SAGARPA | Casanova L.G.,CENID F y MA | Torres C.R.,CENASA | Gallegos S.L.S.,Autonomous University of Queretaro | And 5 more authors.
Preventive Veterinary Medicine | Year: 2012

The molecular fingerprints of 878 isolates of Mycobacterium bovis collected from cattle between 2009 and 2010 in different regions of Mexico were used in this study. One hundred and ninety-four spoligotypes were observed in total with a high degree of heterogeneity. Sixty-four percent of the isolates grouped into just nine spoligotypes, and 27% fell into only two spoligotypes: SB0673 and SB0669; 149 were orphan spoligotypes. The two predominant spoligotypes were found in almost all states in Mexico, especially in central Mexico, where there is a high concentration of dairy cattle; however, some spoligotypes were closely associated with restricted geographical areas. The hypothetical evolutionary relationship among spoligotypes was estimated using the spoligoforest program in the spolTools webpage. Four trees with connected components and nine unconnected nodes were found. The biggest tree had SB0140 strain as a root, suggesting this as the oldest strain in the tree. However, the relationship of this spoligotype with SB0673 and SB0669 was weak. The discriminatory power of spoligotyping for this M. bovis sample of isolates was 0.94, and the recent transmission index (RTI) 0.83, suggesting a high rate of recent transmission of some strains of M. bovis in the population. This parameter indicates that new measures are required to stop the dissemination of tuberculosis in cattle. © 2012 Elsevier B.V.

Pereira-Suarez A.L.,University of Guadalajara | Alvarado-Navarro A.,University of Guadalajara | Alvarado-Navarro A.,Instituto Dermatologico Of Jalisco | Barrietos-Garcia J.G.,Instituto Dermatologico Of Jalisco | And 4 more authors.
Indian Journal of Dermatology, Venereology and Leprology | Year: 2015

Background: Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae, an intracellular parasite that resides within macrophages and cannot be eliminated effectively. Solute carrier family 11a member 1 (Slc11a1) and inducible nitric oxide synthase (iNOS), both expressed in macrophages, play major roles in host defense against several intracellular pathogens. However, the roles of these molecules in natural infection with M. leprae remain unknown. Objective: We aimed to investigate the expression of Slc11a1 and iNOS in macrophages (CD68+ cells) infiltrating skin lesions in leprosy. Methods: Skin biopsies from 48 Mexican patients of leprosy [(33 lepromatous (LL), 15 tuberculoid (TT)] and from 10 healthy controls, were subjected to immunohistochemistry to determine expression of CD68, Slc11a1 and iNOS. Results: We found a high expression of Slc11a1 and iNOS in most lepromatous leprosy samples. In tuberculoid leprosy samples, Slc11a1 expression was moderate or low, and that of iNOS was almost always low. In addition, Slc11a1 and iNOS expression levels were positively associated with bacillary loads in lepromatous leprosy lesions (P = 0.05). Conclusions: These observations suggest that M. leprae infection promotes the expression of Slc11a1 and iNOS in macrophages and that lepromatous leprosy can occur despite this response. © 2015 Indian Journal of Dermatology, Venereology, and Leprology.

Rivera I.,INSA Toulouse | Rivera I.,French National Institute for Agricultural Research | Rivera I.,French National Center for Scientific Research | Mateos J.C.,CIATEJ | And 7 more authors.
Tetrahedron Letters | Year: 2013

Besides the well-known papain, lipolytic activity is another interesting enzymatic activity present in latex from Carica papaya. This lipolytic activity is strongly attached to the latex solid phase, resulting in a naturally immobilized biocatalyst. In this work we describe the kinetic resolution of (R,S)-2-bromophenylacetic acid octyl ester by Carica papaya crude latex and two partially purified latex fractions. Several parameters, such as substrate concentration and solvent effects were studied. The best results were obtained using decane as solvent with 50 mM of substrate and 50 mg/mL enzyme/reaction medium; under these conditions, a high enantioselectivity (E >200) was obtained with crude latex. A twofold increase of the initial rate maintaining E >200 was obtained using purified fractions without protease and without esterase. Lipase from Carica papaya latex is the most enantioselective wild-type enzyme ever described for the studied reaction. © 2013 Elsevier Ltd. All rights reserved.

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