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Frontiers of Materials Science 2017年第3期11卷 250-261页

作者： Alberto ESTRELLA GONZALEZ Maximiliano ASOMOZA Ulises ARELLANO sandra cipagauta diaz Silvia SOLíS Department of Chemistry Metropolitan Autonomous University-lztapalapa P.O. Box 55-532 C.P. 09340 México City México

This study describes the development of mesostructured TiO2 photo- catalysts modified with PO4^3- to improve its specific surface area and reduce the recombination rate of the electron-hole pairs. The mesoporous photocatalyst was successfully incorporated into a high specific surface area silica matrix by the hydrolysis reaction of tetraethyl orthosilicate （TEOS）. Pluronic 123 and phosphoric acid were used as the directing agent for the structure of the mesoporous TiO2 and as a source of phosphorus, respectively, TiO2, P/TiO2, TiO2-SiO2 and P/TiO2-SiO2 materials were characterized by BET, XRD, TEM-EDS, FTIR and UV-vis DRS measurements. The photoactivity of TiO2-SiO2 nanocomposites containing 15 wt.% photocatalystJsilica was evaluated in the degradation reaction of anionic dyes with UV radiation. The proposed nanomaterials showed high potential for applications in the remediation of wastewater, being able to reuse in several cycles of reaction, maintaining its photoactivity and stability. The separation and recovery time of the material is reduced between cycles since no centrifugation or filtration processes are required after the photooxidation reaction.

关键词： photocatalysis phosphated TiO2 TiO2-SiO2 Congo red dye

Redox Regulation of Glycogen Biosynthesis in the Cyanobacterium Synechocystis sp. PCC 6803： Analysis of the AGP and Glycogen Synthases

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Molecular Plant 2014年第1期7卷 87-100页

作者： sandra diaz-Troya Luis Lopez-Maury Ana Maria Sanchez-Riego Miguel Roldan Francisco J. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Americo Vespucio 49 E-41092 Sevilla Spain

Glycogen constitutes the major carbon storage source in cyanobacteria, as starch in algae and higher plants. Glycogen and starch synthesis is linked to active photosynthesis and both of them are degraded to glucose in the dark to maintain cell metabolism. Control of glycogen biosynthesis in cyanobacteria could be mediated by the regulation of the enzymes involved in this process, ADP-glucose pyrophosphorylase （AGP） and glycogen synthase, which were identified as putative thioredoxin targets. We have analyzed whether both enzymes were subjected to redox modification using purified recombinant enzymes or cell extracts in the model cyanobacterium Synechocystis sp. PCC 6803. Our results indicate that both AGP and glycogen synthases are sensitive to copper oxidation. However, only AGP exhibits a decrease in its enzymatic activity, which is recovered after reduction by DTT or reduced thioredoxin （TrxA）, suggesting a redox control of AGP. In order to elucidate the role in redox control of the cysteine residues present on the AGP sequence （C45, C185, C320, and C337）, they were replaced with serine. All AGP mutant proteins remained active when expressed in Synechocystis, although they showed different electrophoretic mobility profiles after copper oxidation, reflecting a complex pattern of cysteines interaction.

关键词： cyanobacteria glycogen Synechocystis thioredoxin redox regulation.

Molecular Docking of 4-Tert-buthyl-bis-(2,6-thiomorpholin-4-ylmethyl)-1-phenol (LQM319) on Fas Receptor (CD95)

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Journal of Cancer Therapy 2013年第1期4卷 176-181页

作者： Oscar Zuniga Victor HVazquez Ana Maria Velazquez Victor HAbrego sandra diaz-Barriga Arceo Patricia Ramirez Roberto diaz Enrique Angeles Laboratorio de Toxicologia y Genetica Departamento de C.BiologicasFacultad de Estudios Superiores CuautitlanUniversidad Nacional Autonoma de MexicoCuautitlan IzcalliMexico Laboratorio de Quimica Medicinal Departamento de Ciencias Quimicas Facultad de Estudios Superiores Cuautitlan Universidad Nacional Autonoma de MexicoCuautitlan IzcalliMrxico.

The balance between cell proliferation and cell growth characterizes tissue homeostasis on one side and cell death on the other side. Fas receptor-mediated apoptosis is a control mechanism for tissue homeostasis, and avoiding this death pathway predisposes to many human diseases, including cancer. Current therapies for this disease are invasive and do not have the desired effect in the control of the disease. In this context, the search for new drugs that contribute to a better treatment is gaining more relevance. 4-tert-butyl-bis-(2,6-thiomorpholin-4-ylmethyl)-1-phenol (LQM319) [1,2] is a drug currently in preclinical stage, and we have shown that it has a hypertensive effect, similar to captopril, in a hypertensive rat model. Different studies have shown that some chemicals that are used as antihypertensive agents have an antineoplastic effect against certain types of cancer, as is the case of hydralazine [3], and captopril [4], among others [5]. On the other hand, it has been reported that morpholine derivatives may activate Fas (CD95)-mediated apoptosis. The aim of the present study was to show the interaction between CD95 (receptor) and thiomorpholine derivatives (ligand) using molecular modeling and docking studies, and to elucidate the possible action mechanism of 4-tert-butyl-bis-(2,6-thiomorpholin-4-ylmethyl)-1-phenol.

关键词： Fas Receptor (CD95) Fas Ligand (FasL) Docking

Evaluation of the frequency of micronucleus in epithelial cells of children exposed to arsenic and heavy metals pollution in a mining area of Mexico

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Chinese Journal Of Geochemistry 2006年第B8期25卷 72-73页

作者： sandra P. Gamino Fernando diaz-Barriga Eugenia M. Gonsebatt Marcos Monroy Laboratorio de Geoquimica y Geomicrobiologia Ambiental Instituto de Metalurgia UASLP / San Luis Potosi S.L.P. México Laboratorio de Toxicologia Ambiental Facultad de Medicina UASLP / San Luis Potosl S.L.P. México Instituto de Investigaciones Biomédicas UNAM/Mexico D.E México

Tibolone modulates neuronal plasticity through regulating Tau, GSK3β/Akt/PI3K pathway and CDK5 p35/p25 complexes in the hippocampus of aged male mice

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Neural Regeneration Research 2017年第4期12卷 588-595页

作者： Teresa Neri-Gomez Judith Espinosa-Raya Sofia diaz Cintra Julia Segura-Uribe sandra Orozco-Suarez Juan Manuel Gallardo Christian Guerra-Araiza Unidad de Investigación Médica en Farmacología Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Ciudad de México México Laboratorio de Farmacología Conductual Escuela Superior de Medicina Instituto Politécnico Nacional Plan de San Luis y Díaz Mirón Col. Sto. Tomás Ciudad de México México Departamento de Neurobiología del Desarrollo y Neurofisiología Instituto de Neurobiología Universidad Nacional Autónoma de México Campus Juriquilla Querétaro Querétaro México Enfermedades Neurológicas (Neurological Diseases) Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Ciudad de México México Enfermedades Nefrológicas (Kidney Diseases) Hospital de Especialidades Centro Medico Nacional Siglo XXI Instituto Mexicano del Seguro Social Ciudad de Mexico Mexico

Aging is a key risk factor for cognitive decline and age-related neurodegenerative disorders. Also, an age-related decrease in sex steroid hormones may have a negative impact on the formation of neurofibrillary tangles （NFTs）; these hormones can regulate Tau phosphorylation and the principal kinase GSK3β involved in this process. Hormone replacement therapy decreases NFTs, but it increases the risk of some types of cancer. However, other synthetic hormones such as tibolone （TIB） have been used for hormone replacement therapy. The aim of this work was to evaluate the long-term effects of TIB （0.01 mg/kg and 1mg/kg, intragastrically for 12 weeks） on the content of total and hyperphosphorylated Tau （PHF-1） proteins and the regulation of GSK3β/Akt/PI3K pathway and CDK5/p35/p25 complexes in the hippocampus of aged male mice. We observed that the content of PHF-1 decreased with TIB administration. In contrast, no changes were observed in the active form of GSK3β or PI3K. TIB decreased the expression of the total and phosphorylated form of Akt while increased that of p110 and p85. The content of CDK5 was differentially modified with TIB： it was increased at low doses and decreased at high doses. When we analyzed the content of CDK5 activators, an increase was found on p35; however, the content of p25 decreased with administration of low dose of TIB. Our results suggest a possible mechanism of action of TIB in the hippocampus of aged male mice. Through the regulation of Tau and GSK3β/Akt/PI3K pathway, and CDK5/p35/p25 complexes, TIB may modulate neuronal plasticity and regulate learning and memory processes.

关键词： nerve regeneration Tibolone hippocampus aged mice sex steroids Akt GSK3β PI3K neuralplasticity Tau neurofibrillary tangles neural regeneration

Satisfaction of the Service Provider with the Organization of the Timely Cervical Cancer Detection Program

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Health 2017年第2期9卷 289-298页

作者： Gutierrez-Enriquez sandra Olimpia Teran-Figueroa Yolanda Gaytan-Hernandez Dario diaz-Oviedo Aracely Zuniga-Martinez Ma.de Lourdes Hernandez-Nava Nereyda Cruz Ortiz Maribel Perez Rodriguez Maria del Carmen Ramirez-Ramirez Rocio Faculty of Nursing and Nutrition Autonomous University of San Luis PotosiSan Luis PotosiMexico Academic Coordination Altiplano Region Autonomous University of San Luis PotosiSan Luis PotosiMexico

Cervical cancer is a priority health problem in Mexico. The objective of this work was to know the degree of satisfaction of the service provider with the organization of the program of Timely Detection of Cervical Cancer, specifically in taking of the cervical cytology. The study design was observational, transversal and prospective conducted from January to May 2015 in Jurisdiction 1 of the Health Services of San Luis Potosí, Mexico, in 20 health centers. Participants were 87 service providers whose function is to take cervical cytology (Pap smears). A 32-question questionnaire was applied, with Likert scale with 5 levels of response: 1 (dissatisfied), 2 (little satisfied), 3 (indifferent), 4 (satisfied) and 5 (very satisfied). The score range was 32 points (minimum job satisfaction) up to 160 points (Maximum job satisfaction). We analyzed 2 dimensions: 1) intrinsic factors that have to do with motivation and professional recognition, and 2) extrinsic factors related to infrastructure, materials, remuneration and labor policies. Each factor consisted of four categories. Descriptive statistics and linear correlation of Pearson were applied for the analysis of data. Participants signed an informed consent letter. Of 4 categories, in the intrinsic dimension, the one with the highest percentage of satisfaction was “delegation of activities” with 28.8%. In the extrinsic dimension, the category with the highest percentage of satisfaction was “infrastructure and materials” with 49.4%;while satisfaction increase in intrinsic dimensions also does in extrinsic dimensions, such correlations are significant (p < 0.05), except between delegation of activities and remuneration (r = 0.074 and p = 0.497). The higher hierarchical level, the men, the bachelor academic level and older people showed the highest level of satisfaction.

关键词： Job Satisfaction Cervical Cancer Health Providers