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San Luis Potosi, Mexico

Alanis C.,National Autonomous University of Mexico | Natividad R.,National Autonomous University of Mexico | Barrera-Diaz C.,National Autonomous University of Mexico | Martinez-Miranda V.,University of Central Mexico | And 2 more authors.
Applied Catalysis B: Environmental | Year: 2013

This work aims to present a study of the adsorption and photocatalytic reduction of Cr(VI) by ZnAl, MgZnAl and MgAl mixed oxides derived from layered double hydroxides (LDHs). The effect of variables like Zn content and pH (3 and 6.5) on Cr(VI) removal efficiency is presented. The catalysts were characterized by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The reaction progress was verified by UV/vis spectrophotometry with a colorimetric method. A maximum of 99.5% Cr(VI) was photocatalytically removed and this process was approximately two times faster than adsorption. In addition, it was found that the use of these materials does not imply the addition of further chemicals to regulate pH since the free basic pH of the catalyst-contaminant suspension positively affects both adsorption and photo-reduction kinetics. © 2013 Elsevier B.V. Source

Gonzalez P.G.,University of Central Mexico | Pliego-Cuervo Y.B.,IT de Orizaba
Chemical Engineering Research and Design | Year: 2014

Mesoporous activated carbon (surface area of 608 m2/g) has achieved high efficiency in removal of cadmium, mercury and zinc ions from water solution. The proposed low-cost adsorbent was physically activated with water steam from the bamboo species Bambusa vulgaris striata. The batch studies suggested an activated carbon dose of 0.6g/L, solution pH of 9 and an equilibrium time of 16h in static conditions. The pseudo-second order equations represented the adsorption kinetics with high correlation. Fitting of the experimental results to the Langmuir, Freundlich, Redlich-Peterson and Toth isotherm models showed an almost homogeneous surface coverage and presence of physical adsorption. The highest adsorption capacities, calculated from the Langmuir model, are 239.45, 248.05 and 254.39 mg/g of cadmium, mercury and zinc, respectively. © 2014 The Institution of Chemical Engineers. Source

Keystone E.C.,Mount Sinai Hospital | Kremer J.M.,Albany Medical College | Russell A.,University of Alberta | Box J.,Box Arthritis and Rheumatology of the Carolinas | And 8 more authors.
Annals of the Rheumatic Diseases | Year: 2012

Objective: To assess safety, immunogenicity and efficacy in rheumatoid arthritis (RA) patients switched from longterm intravenous to subcutaneous (SC) abatacept. Methods: In this phase IIIb, open-label, single-arm trial, patients who completed ≥4 years of intravenous abatacept (in long-term extensions of two phase III studies) were enrolled to receive SC abatacept (125 mg/week). The primary objective was safety during the first 3 months after switching from intravenous therapy. Results: 123 patients entered the study (mean Disease Activity Score 28 (based on C reactive protein) and HAQ-DI of 3.4 and 0.94, respectively). At month 3, 120 (97.6%) patients were continuing to receive SC abatacept; no patients discontinued due to lack of efficacy. Adverse events (AEs) were reported in 49 (39.8%) patients through month 3. One patient (0.8%) discontinued due to an AE and one patient (0.8%) experienced a serious AE. Two (1.6%) patients had SC injection site reactions (erythema, pain), both with mild intensity. Clinical efficacy was maintained throughout. Limited impact on immunogenicity was observed when switching routes of administration. Conclusion: These data demonstrate that patients can switch from long-term monthly intravenous abatacept to a weekly fixed dose of 125 mg SC abatacept with no increased safety concerns. This study further supports SC abatacept as an alternative treatment option for patients with RA. Source

Feria-Ortiz M.,University of the East of Mexico | Manrquez-Morn N.L.,University of Central Mexico | De Oca A.N.-M.,National University of Costa Rica
Herpetological Monographs | Year: 2011

The Mexican Plestiodon brevirostris species group (Squamata: Scincidae) is composed of seven nominal species. The wide-ranging P. brevirostris is a polytypic species composed of five subspecies: P. b. brevirostris, P. b. bilineatus, P. b. dicei, P. b. indubitus, and P. b. pineus. A tree-based approach for species delimitation with mtDNA data was used to test the traditional species-level taxonomy of P. brevirostris preliminarily. A haplotype phylogeny for all of the species and subspecies in the P. brevirostris group, except P. colimensis, was inferred. The mtDNA data consisted of sequences encompassing the genes encoding 16S rRNA (part), ND1, and associated tRNAs (1355 base pairs), which were analyzed with Bayesian methods. Then, a search for diagnostic morphological characters for the putative species delimited by this approach was performed. The results indicate that the P. brevirostris group is paraphyletic with respect to P. lynxe, and that P. brevirostris actually is composed of at least five distinct lineages disguised by traditional taxonomy: P. b. brevirostris, P. b. bilineatus, P. b. dicei, and the eastern populations of P. b indubitus (from Morelos, Guerrero, and México) represent distinct species, whereas the western populations of P. b. indubitus (from Colima and Jalisco) represent an undescribed species. The data cannot resolve whether P. b. pineus is conspecific with P. b. dicei or P. b. dicei is a paraphyletic (?=?nonexclusive) species relative to an exclusive P. b. pineus. Thus, the status of P. b. pineus remains uncertain. The haplotype phylogeny also suggests that P. b. brevirostris may represent more than one species. © 2011 The Herpetologists' League, Inc. Source

Salgado-Miranda C.,University of Central Mexico | Loza-Rubio E.,National Institute for Forestry | Rojas-Anaya E.,National Institute for Forestry | Garcia-Espinosa G.,National Autonomous University of Mexico
Expert Review of Vaccines | Year: 2013

Since 1970, aquaculture production has grown. In 2010, it had an annual average rate of 6.3% with 59.9 million tons of product and soon could exceed capture fisheries as a source of fishery products. However, the occurrence of viral diseases continues to be a significant limiting factor and its control is important for the development of this sector. In aquaculture farms, fish are reared under intensive culture conditions, and the use of viral vaccines has enabled an increase in production. Several types of vaccines and strategies of vaccination have been developed; however, this approach has not reached the expected goals in the most susceptible stage (fingerlings). Currently, there are inactivated and recombinant commercial vaccines, mainly for salmonids and cyprinids. In addition, updated genomic and proteomic technology has expedited the research and expansion of new vaccine models, such as those comprised of subunits or DNA. The objective of this review is to cover the various types of viral vaccines that have been developed and are available for bony fishes, as well as the advantages and challenges that DNA vaccines present for massive administration in a growing aquaculture, possible risks for the environment, the controversy regarding genetically modified organisms and possible acceptance by consumers. © 2013 2013 Expert Reviews Ltd. Source

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