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Historical fluxes of metal and metalloids in an aquatic ecosystem affected by land-use change and mining activities in northwestern Mexico

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International Journal of Sediment Research 2023年第5期38卷 724-738页

作者： Ochoa-contreras Roberto Jara-Marini Martín enrique Ruiz-Fernández Ana Carolina Sanchez-Cabeza Joan Albert Meza-Figueroa Diana Pérez-Bernal libia Hascibe Posgrado en Ciencias Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo 2. Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo Unidad Acad emica Mazatlán Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de M exico Departamento de Geología División de Ciencias Exactas y Naturales Universidad de Sonora Rosales y Encinas

Freshwater reservoirs are essential owing because of their ecological, economic, and social *** are particularly vulnerable to contamination, as of metal and metalloids, derived from anthropogenic activities like mining. The temporal variations in trace element concentrations(arsenic(As),mercury(Hg), chromium(Cr), copper(Cu), nickel(Ni), lead(Pb), and zinc(Zn)), enrichment, fluxes, and possible sources were evaluated by studying two sediment cores from the la Angostura(ANG) Reservoir(northwest Mexico), using210Pb geochronology. The enrichment factors showed from null to minor enrichment for most elements, but moderate to severe enrichment of mercury(Hg). Most trace element concentrations had a detrital origin, and notable Hg concentration increases since the past decade were associated with severe drought periods, likely resulting from wildfires. The observed sediment concentrations of As and Hg can cause adverse effects on biota in the ecosystem since they are above the probable effect level(PEl). Development of strategies for metal attenuation in this reservoir is recommended and metals should be controlled until specific ecotoxicological studies are performed.

关键词： Aquatic ecosystems ~(210)Pb geochronology Mining activities Metals Metalloids Enrichment factors

The transcription factor ZEB1 promotes chemoresistance in prostate cancer cell lines

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Asian Journal of Andrology 2019年第5期21卷 460-467页

作者： Octavio Orellana-Serradell Daniela Herrera enrique A Castellon Hector R contreras Department of Basic and Clinical Oncology Faculty of MedicineUniversity of ChileIndependenciaSantiago 8380453Chile

One of the factors promoting tumoral progress is the abnormal activation of the epithelial-mesenchymal transition(EMT)program which has been associated with chemoresistance in tumoral *** transcription factor zinc finger E-box-binding homeobox 1(ZEB1),a key EMT activator,has recently been related to docetaxel resistance,the main chemotherapeutic used in advanced prostate cancer *** mechanisms involved in this protective effect are still *** a previous work,we demonstrated that ZEB1 expression induced an EMT-like phenotype in prostate cancer cell *** this work,we used prostate cancer cell lines 22Rvl and DU145 to study the effect of ZEB1 modulation on docetaxel resistance and its possible *** results showed that ZEB1 overexpression conferred to 22Rvl cell resistance to docetaxel while its silencing made DU145 cells more sensitive to *** of resistance markers showed no presenee of ATP-binding cassette subfamily B member 1(MDR1)and no changes in breast cancer resistance protein(BCRP)or ATP-binding cassette subfamily C member 10(MRP7).However,a correlation between ZEB1,multidrug resistance-associated protein 1(MRP1),and ATP-binding cassette subfamily C member 4(MRP4)expression was ***4 inhibition,using MK571,resensitized cells with ZEB1 overexpression to docetaxel *** addition,modulation of ZEB1 and subsequent change in MRP4 expression correlated with a lower apoptotic response to docetaxel,characterized by lower B-cell lymphoma 2(Bcl2),high BCl2-associated X protein(Bax),and high active caspase 3 *** response to docetaxel in our model seems to be mediated mainly by activation of the apoptotic death *** results showed that modulation of MRP4 could be a mediator of ZEBl-related resistance to docetaxel in prostate cancer,making it a possible marker for chemotherapy response in patients who do not express MDR1.

关键词： chemoresistance prostate cancer ZEB1

The transcription factor ZEB1 promotes an aggressive phenotype in prostate cancer cell lines

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Asian Journal of Andrology 2018年第3期20卷 294-299页

作者： Octavio Orellana-Serradell Daniela Herrera enrique A Castellon Hector R contreras Department of Basic and Clinical Oncology Faculty of Medicine University of Chile Independencia Santiago 8380453 Chile.

It has been reported that one of the factors that promotes tumoral progression is the abnormal activation of the epithelial-mesenchymal transition program. This process is associated with tumoral cells acquiring invasive and malignant properties and has the transcription factor zinc finger E-box-binding homeobox 1 （ZEB1） as one of its main activators. However, the role of ZEB1 in promoting malignancy in prostate cancer （PC, a） is still unclear. Here, we report that ZEB1 expression correlates with Gleason score in PCa samples and that expression of ZEB1 regulates epithelial-mesenchymal transition and malignant characteristics in PCa cell lines. The results showed that ZEB1 expression is higher in samples of higher malignancy and that overexpression of ZEB1 was able to induce epithelial-mesenchymal transition by upregulating the mesenchymal marker Vimentin and downregulating the epithelial marker E-Cadherin. On the contrary, ZEB 1 silencing repressed Vimentin expression and upregulated E-Cadherin. ZEB1 expression conferred enhanced motility and invasiveness and a higher colony formation capacity to 22Rvl cells whereas DU145 cells with ZEB1 silencing showed a decrease in those same properties. The results showed that ZEB1 could be a key promoter of tumoral progression toward advanced stages of PC, a.

关键词： epithelial-mesenchymal transition prostate cancer transcriptional repression ZEB1

Secreted protein acidic and rich in cysteine(SPARC)induces epithelial-mesenchymal transition,enhancing migration and invasion,and is associated with high Gleason score in prostate cancer

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Asian Journal of Andrology 2019年第6期21卷 557-564页

作者： Fernanda lopez-Moncada Maria Jose Torres enrique A Castellon Hector R contreras Department of Basic and Clinic Oncology Faculty of Medic泊eUniversity of ChileSantiago 8389100Chile

Secreted protein acidic and rich in cysteine(SPARC)is a matricellular protein highly expressed in bone tissue that acts as achemoattractant factor promoting the arrival of prostate cancer(PCa)cells to the bone ***,the contribution of SPARCduring the early stages of tumor progression remains *** this study,we show that SPARC is highly expressed in PCa tissueswith a higher Gleason *** stable knockdown and overexpression of SPARC in PC3 and lNCaP cells,respectively,here wedem on strate that en doge nous SPARC induces the epithelial-mesenchymal tran sition(EMT),decreasing E-cadheri n and cytokeratin18 and increasing N-cadheri n and vime ***,SPARC in duces the expression of EMT regulatory tran scription factors Snailfamily transcriptional repressor 1(Snail),Snail family transcriptional repressor 2(Slug),and zinc finger E-box binding homeobox 1(Zeb1).In addition,SPARC knockdown in PC3 cells decreases migration and invasion in vitro,without modifying cell *** results indicate that SPARC might facilitate tumor progression by modifying the cellular phenotype in cancer cells.

关键词： epithelial-mesenchymal transition invasion migration prostate cancer secreted protein acidic and rich in cysteine(SPARC)

Glutathione peroxidase activity in cell cultures from different regions of human epididymis

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Asian Journal of Andrology 2005年第1期7卷 33-37,页

作者： enrique Castellon Hernan Rioseco Juan Rojas Michel Royer Eduardo Salas Hoctor contreras Christian Huidobro Physiology and Biophysics Program Institute of Biomedical Sciences Faculty of Medicine University. of Chile Santiago 6530499 Chile Urology Department Clinic Hospital J. J. Aguirre University of Chile Santiago 6530499 Chile

Aim: To study the secretory activity and androgen regulation of glutathione peroxidase (GPx) in epithelial cell cultures from human epididymis. Methods: Tissue was obtained from patients undergoing therapeutic orchidectomy for prostatic cancer. Epithelial cell cultures were obtained from the caput, corpus and cauda epididymides. Enzymatic activity was measured in conditioned media by colorimetric methods in absence or presence of 1, 10 or 100 nrnoI.l^(-1) testosterone. The effect of 1 μmol.l^(-1) flutamide was also evaluated. Results: GPx activity was higher in cultures from corpus and cauda than caput epididymidis. The presence of different concentrations of testosterone increase enzyme activity in cell cultures from all epididymal regions. Addition of flutamide reverses the androgen dependent increase of GPx activity. Conclusion: GPx activity is secreted from human epididymal cells in a region dependent manner and is regulated by androgens.

关键词： glutathione peroxidase human epididymis cell culture androgen regulation

Structural Analysis of TiC and TiC-C Core-Shell Nanostructures Produced by Pulsed-laser Ablation

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Journal of Materials Science and Chemical Engineering 2023年第7期11卷 1-13页

作者： luis enrique Iniesta Piña Miguel Ángel Camacho lópez rafael Vilchis Néstor Víctor Hugo Castrejón Sánchez Delfino Reyes contreras Mestría en Ciencia de Materiales Facultad de Química Campus Rosedal Universidad Autónoma del Estado de México Toluca México laboratorio de Fotomedicina Biofotónica y Espectroscopía Láser de Pulsos Ultracortos Facultad de Medicina Universidad Autónoma del Estado de México Toluca México Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM Toluca México TecNM/Tecnológico de Estudios Superiores de Jocotitlán Jocotitlán México laboratorio de Acústica y Nanomateriales Facultad de Ciencias Campus el Cerrillo Universidad Autónoma del Estado de México Toluca México

This paper reports on the ablation process of a pure Ti solid target immersed in a C-enriched acetone solution, leading to the production of titanium carbide (TiC) and Ti-C core-shell nanostructures. The used route of synthesis is generally called pulsed laser ablation in liquid (PlAl). The presence of carbon structures in the solution contributed to the carbon content in the produced Ti-based nanomaterials. The atomic composition of the produced nanostructures was analyzed using SEM-EDS, while TEM micrographs revealed the formation of spherical TiC and core-shell nanostructures ranging from 40 to 100 nm. The identification of atomic planes by HRTEM confirmed a 10 nm diameter C-shell with a graphite structure surrounding the Ti-core. raman spectroscopy allowed for the identification of D and G peaks for graphite and a raman signal at 380 and 600 cm−1, assigned to TiC. The results contribute to the state-of-the-art production of TiC and Ti-C core-shell nanostructures using the PlAl route.

关键词： laser Ablation TiC Nanoparticles Core-Shell Nanoparticles Pulsed laser

Further studies on the effects of acamprosate on tolerance to the analgesic effects of morphine and NO synthesis in the brain

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Health 2013年第11期5卷 1-6页

作者： Jacqueline Sepúlveda Andrea Ortega Jorge Roa enrique contreras Department of Pharmacology School of Biological Sciences University of Concepción Concepción Chile Department of Pharmacology School of Biological Sciences University of Concepción Concepción Chile Department of Physiology School of Biological Sciences University of Concepción Concepción Chile Department of Pre-Clinical and Clinical Sciences School of Medicine Catholic University of the Holy Conception Concepción Chile

The aim of this work was to investigate whether acamprosate modifies the expression of the enzyme responsible for neuronal NO synthesis (nNOS) in the nucleus accumbens (NAc) of mice chronically treated with morphine and during the abstinence syndrome induced by naloxone. The enzyme was monitored by the NADPH diaphorase method. The number of cells stained for NADPH diaphorase in the NAc of mice was counted in 40 μm thick coronal brain slices at 40X. The intensity of the histochemical reaction of stained cells from naive morphine plus saline and morphine plus acamprosate treated mice was analyzed by Image Pro Plus 4.5.1. Morphine administered in a slow release preparation increased the stain intensity of the positive neurons. The increase in the NADPH staining persisted after naloxone was given to mice chronically treated with morphine. Acamprosate antagonized the effects induced by chronic morphine treatment in the NAc of mice. These results indicate that up-regulation of nNOS in the NAc is a consequence of the sustained effects of morphine stimulation, which, in turn, may result from an increased in glutamate release during the abstinence syndrome.

关键词： Morphine Nitric Oxide Nucleus Accumbens Acamprosate

syndecan-1和-2表达形式的变化可以预测前列腺癌生化复发

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Asian Journal of Andrology 2011年第3期13卷 476-480,514页

作者： Rodrigo ledezma Federico Cifuentes Ivan Gallegos Juan Fulla enrique Ossandon enrique A Castellon Hector R contreras laboratory of Molecular and Cellular Andrology Physiology and Biophysics Program. Institute of Biomedical Sciences Faculty of Medicine University of Chile Santiago 70005 Chile pathology Service Clinic Hospital University of Chile Santiago 70005 Chile Urology Service Clinic Hospital University of Chile Santiago 70005 Chile

The clinical features of prostate cancer do not provide an accurate determination of patients undergoing biochemical relapse and are therefore not suitable as indicators of prognosis for recurrence. New molecular markers are needed for proper pre-treatment risk stratification of patients. Our aim was to assess the value of altered expression of syndecan-1 and -2 as a marker for predicting biochemical relapse in patients with clinically localized prostate cancer treated by radical prostatectomy. The expression of syndecan-1 and -2 was examined by immunohistochemical staining in a series of 60 paraffin-embedded tissue samples from patients with localized prostate cancer. Ten specimens from patients with benign prostatic hyperplasia were used as non-malignant controls. Semiquantitative analysis was performed to evaluate the staining patterns. To investigate the prognostic value, Kaplan-Meier survival curves were performed and compared by a log-rank test. In benign samples, syndecan-1 was expressed in basal and secretory epithelial cells with basolateral membrane Iocalisation, whereas syndecan-2 was expressed preferentially in basal cells. In prostate cancer samples, the expression patterns of both syndecans shifted to granular-cytoplasmic Iocalisation. Survival analysis showed a significant difference （P〈0.05） between normal and altered expression of syndecan-1 and -2 in free prostate-specific antigen recurrence survival curves. These data suggest that the expression of syndecan-1 and -2 can be used as a prognostic marker for patients with clinically localized orostate cancer, improving the larostate-specific antigen recurrence risk stratification.

关键词： biochemical recurrence prostate cancer syndecans

Situational Diagnosis of the Social Sphere of Elders living in Retirement Homes

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Advances in Aging Research 2015年第2期4卷 42-46页

作者： Verónica Benavides Pando Martha Ornelas contreras Jesús enrique Peinado Pérez Juan Cristóbal Barrón luján lepoldo Refugio lópez Baca Faculty of Physical Culture Sciences Autonomous University of Chihuahua Chihuahua Mexico

A situational diagnosis of the social sphere of elder permanent residents at retirement homes in Chihuahua City was created with the aid of the Social Resource Scale instrument. From the 51 participants, there were 30 female and 21 male elders. The results and conclusions of the present study highlight two major needs: a systematic assessment of permanent residents in retirement homes and the implementation of a physical activation program. The proposed physical activation program must focus on both, the recovery of motor independence and the increase of socialization activities which allows members of the retired community to improve their daily routine performance and lessens the work load on their caretakers.

关键词： Situational Diagnosis Elder Social Sphere