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Liver histological changes and lipid peroxidation in the amphibian Ambystoma mexicanum induced by sediment elutriates from the Lake Xochimilco

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Journal of Environmental Sciences 2016年第8期28卷 156-164页

作者： Esperanza Ortiz-Ordonez Eugenia López-López Jacinto Elías Sedeno-Díaz Esther Uría Ignacio Andrés Morales María Estela Pérez Mineko Shibayama Instituto Politécnico Nacional Depto.de Formación Básica e InterdisciplinariaCICS-USTAv.de los Maestros s/n.Col.Sto Instituto Politécnico Nacional Laboratorio de Evaluación de la Salud de Ecosistemas AcuáticosENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Instituto Politécnico Nacional Coordinación Politécnica para la SustentabilidadEdificio de la Biblioteca Nacional3er PisoAv.Instituto Politécnico Nacional s/nesq.Wilfrido MassieuCol Instituto Politécnico Nacional Laboratorio de HistologíaENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Unidad de Servicio Académico Acuario BiologíaFacultad de CienciasUniversidad Autónoma de MéxicoCiudad Universitaria laboratorio de Infectómica Centro de Investigación y de Estudios Avanzados del IPNAv.Instituto Politécnico Nacional

Lacustrine sediments accumulate pollutants that input from the lake watershed and can be released to the water column by sediment resuspension; thus, pollutants can change their bioavailability and exert adverse effects to aquatic biota. Shallow-urban lakes are particularly susceptible to receive pollutants from urban discharges and sediment resuspension. Lake Xochimilco, in Mexico City, an urban-shallow lake, faces multiple problems： urban sprawl, overexploitation of aquifers, drying of springs, discharge of wastewater from treatment plants, and sediment resuspension. The aquatic biota living in this ecosystem is continuously exposed to the release of pollutants from the sediments. We assessed the risk that pollutants released from sediments from Lake Xochimilco, Touristic（TZ） and Agriculture zone（AZ）, can exert on a native amphibian species of the lake（Ambystoma mexicanum） through exposure bioassays to sediment elutriates. We evaluate alterations in the amphibian by three approaches： biochemical（level of lipid peroxidation,LPO）, cellular（ultrastructure） and the liver histology of A. mexicanum and we compare them with a batch control. Additionally, we assessed heavy metals（Pb, Cd and Hg） in *** from TZ showed the highest concentrations of the metals assessed. Organisms exposed to sediment elutriates from either study sites showed higher LPO values than control organisms（p 〈 0.05）. Organisms exposed to elutriates from the TZ showed the most conspicuous damages： hepatic vasodilation of sinusoids, capillaries with erythrocytes,leukocyte infiltration and cytoplasmic vacuolation in hepatocytes. The biological responses assessed reflected the risk that faces A. mexicanum when is exposed for prolonged periods to sediment resuspension in Lake Xochimilco.

关键词： Elutriates Amphibian Liver Histological alterations Ultrastructure Oxidative stress Metals Urban lake

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An Architecture for Software Engineering Gamification

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Tsinghua Science and Technology 2020年第6期25卷 776-797页

作者： Oscar Pedreira Felix Garcia Mario Piattini Alejandro Cortinas Ana Cerdeira-Pena the Universidade da Coruna Centro de Investigacion CITICLaboratorio de Bases de DatosFacultade de InformaticaElvinaA Coruna15071Spain the Universidad de Castilla-La Mancha Grupo AlarcosEscuela Superior de InformaticaPaseo de la Universidad4Ciudad Real13071Spain.

Gamification has been applied in software engineering to improve quality and results by increasing people’s motivation and engagement.A systematic mapping has identified research gaps in the field,one of them being the difficulty of creating an integrated gamified environment comprising all the tools of an organization,since most existing gamified tools are custom developments or *** this paper,we propose a gamification software architecture that allows us to transform the work environment of a software organization into an integrated gamified environment,i.e.,the organization can maintain its tools,and the rewards obtained by the users for their actions in different tools will mount *** developed a gamification engine based on our proposal,and we carried out a case study in which we applied it in a real software development *** case study shows that the gamification engine has allowed the company to create a gamified workplace by integrating custom-developed tools and off-the-shelf tools such as Redmine,TestLink,or JUnit,with the gamification *** main advantages can be highlighted:(i)our solution allows the organization to maintain its current tools,and(ii)the rewards for actions in any tool accumulate in a centralized gamified environment.

关键词： gamification software engineering gamification architecture gamification engine

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Optimized high performance liquid chromatography–ultraviolet detection method using core-shell particles for the therapeutic monitoring of methotrexate

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Journal of Pharmaceutical Analysis 2016年第2期6卷 103-111页

作者： milagros montemurro maría m.de zan juan c.robles laboratorio de Control de Calidad de Medicamentos Facultad de Bioqufmica y Ciendas Biologicas Universidad Nacional del Litoral Santa Fe Argentina

Methotrexate （MTX） is an antineoplastic drug, and due to its high toxicity, the therapeutic drug mon- itoring is strictly conducted in the clinical practice. The chemometric optimization and validation of a high performance liquid chromatography （HPLC） method using core-shell particles is presented for the determination of MTX in plasma during therapeutic monitoring. Experimental design and response surface methodology （RSM） were applied for the optimization of the chromatographic system and the analyte extraction step. A Poroshel1120 EC-C18 （3.0 mm × 75 mm, 2.7 μm） column was used to obtain a fast and efficient separation in a complete run time of 4 min. The optimum conditions for the chroma- tographic system resulted in a mobile phase consisting of acetic acid/sodium acetate buffer solution （85.0 mM, pH =4.00） and 11.2% of acetonitrile at a flow rate of 0.4 mL/min. Selectivity, linearity, accuracy and precision were demonstrated in a range of 0.10-6.0 μM of MTX. The application of the optimized method required only 150μL of patient plasma and a low consumption of solvent to provide rapid re- sults.

关键词： HPLC Core-shell particles Methotrexate Drug monitoring

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Novel TINF2 gene mutation in dyskeratosis congenita with extremely short telomeres:A case report

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World Journal of Clinical Cases 2022年第33期10卷 12440-12446页

作者： Verónica Judith Picos-Cárdenas Saúl Armando Beltrán-Ontiveros JoséAlfonso Cruz-Ramos JoséAlfredo Contreras-Gutiérrez Eliakym Arámbula-Meraz Carla Angulo-Rojo Alma Marlene Guadrón-Llanos Emir Adolfo Leal-León Dora María Cedano-Prieto Juan Pablo Meza-Espinoza laboratorio de Genética Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Centro de Investigación y Docencia en Ciencias de la Salud Hospital Civil de CuliacánUniversidad Autónoma de SinaloaCuliacán 80030SinaloaMexico departamento de Clínicas Médicas Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340JaliscoMexico Facultad de Medicina Universidad Autónoma de SinaloaCuliacán 80018SinaloaMexico laboratorio de Genética y biología Molecular Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de SinaloaCuliacán 80010SinaloaMexico laboratorio de Neurociencias Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico laboratorio de Diabetes y Comorbilidades Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Facultad de Medicina Universidad Autónoma de TamaulipasMatamoros 87349TamaulipasMexico

BACKGROUND Dyskeratosis congenita is a rare disease characterized by bone marrow failure and a clinical triad of oral leukoplakia,nail dystrophy,and abnormal skin *** genetics of dyskeratosis congenita include mutations in genes involved in telomere maintenance,including *** SUMMARY Here,we report a female patient who presented thrombocytopenia,anemia,reticulate hyperpigmentation,dystrophy in fingernails and toenails,and leukoplakia on the tongue.A histopathological study of the skin showed dyskeratocytes;however,a bone marrow biopsy revealed normal cell *** patient was diagnosed with dyskeratosis congenita,but her family history did not reveal significant ***-exome sequencing showed a novel heterozygous punctual mutation in exon 6 from the TINF2 gene,namely,NM_001099274.1:-c.854delp.(Val285-Alafs*32).An analysis of telomere length showed short telomeres relative to the patient’s *** The disease in this patient was caused by a germline novel mutation of TINF2 in one of her parents.

关键词： Dyskeratosis congenita TINF2 Germline mutation Novel mutation Short telomeres Case report

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Biofilm and Helicobacter pylori:From environment to human host

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World Journal of Gastroenterology 2014年第19期20卷 5632-5638页

作者： Apolinaria García María José Salas-Jara Carolina Herrera Carlos González laboratorio de Patogenicidad Bacteriana Departamento de MicrobiologíaFacultad de Ciencias BiológicasUniversidad de ConcepciónConcepción 4030000Chile

Helicobacter pylori(***)is a Gram negative pathogen that selectively colonizes the human gastric *** 50%of the world population is infected with *** reaching up to 90%of infected individuals in developing *** the increased impact upon public health care,its reservoir and the transmission pathway of the species has not been clearly established *** studies allowed the detection of *** in various aquatic environments,even forming biofilm in tap water distribution systems in several countries,suggesting a role of water as a possible reservoir of the *** persistence of human infection with *** and the resistance of clinical isolates to commonly used antibiotics in eradication therapy have been related to the genetic variability of the species and its ability to develop biofilm,demonstrated both in vivo and in vitro ***,during the last years,experimental work with this pathogen has been focused in the search for biofilm inhibitors and biofilm destabilizing ***,only two *** biofilm disrupting agents have been successfully used:Curcumin-a natural dye-and N-acetyl cysteine-a mucolytic agent used in respiratory *** main goal of this review was to discuss the evidences available in the literature supporting the ability of *** to form biofilm upon various surfaces in aquatic environments,both in vivo and in *** results published and our own observations suggest that the ability of *** to form biofilm may be important for surviving under stress conditions or in the spread of the infection among humans,mainly through natural water sources and water distribution systems.

关键词： Helicobacter pylori Biofilm,Water Infection

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Assessing conservation practices in Amalacaxco Gorge (Izta-Popo National Park, Central Mexico) using fallout 137Cs and Optically Stimulated Luminescence (OSL)

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Journal of Mountain Science 2018年第3期15卷 447-460页

作者： MUNOZ-SALINAS E CASTILLO M departamento de Geología Regional Universidad Nacional Autónoma de México Ciudad UniversitariaCiudad de MexicoMexico laboratorio Nacional de Geoquimicay Mineralogia Ciudad Universitaria Ciudad de Mexico Mexico

This study aims to assess conservation practices in Izta-Popo National Park(Central Mexico) by evaluating the mechanisms of sediment transfer. We applied a methodology based on fallout ^(137)Cs and optically stimulated luminescence(OSL) analysis. This was tested in the upper catchment of Amalacaxco Gorge, selected for being one of the sectors of the park in which man-made actions have been implemented in last decades to favor forest growth in the alpine grassland and to reduce the effect of water runoff. We quantified the ^(137)Cs activity using gamma and beta spectrometry of fine sediment grains extracted from the surface of parcels of 0.4 m2 in areas of natural forest, natural alpine grassland, alpine grassland with conservation practices, ravines and trails. In general, ^(137)Cs values increases as local slope decreases as it was expected. The natural forest is the most stable area in terms of soil erosion and sediment accumulation and, mean ^(137)Cs activity was taken as reference to assess cumulative zones, with higher ^(137)Cs values and erosive, with lower. We found that trails are accumulative surfaces but in other areas, erosion predominates. Man-made ditches, trenches and afforestation in the alpine grassland have higher ^(137)Cs values than thenatural grassland, which indicates that conservation practices are limiting the sediment transfer from hillslopes to channels, however, soil retention is less than in the natural grassland. Additionally, we evaluated the luminescence(OSL) values obtained from samples extracted from the sediment transported in ravines that are cutting into different sectors of the study area to assess the grade of resetting of fluvial materials. These luminescence results indicated that the sediment transported in ravines that are cutting into the natural forest and alpine grassland is bleached more efficiently than the sediment transported in the alpine grassland with conservation practices. Results of fallout ^(137)Cs and luminesce

关键词： Sediment transfer Soil erosion Natural protected areas Alpine grassland Caesium-137 Optically stimulated luminescence

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HP0953-hypothetical virulence factor overexpresion and localization during Helicobacter pylori infection of gastric epithelium

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World Journal of Gastroenterology 2022年第29期28卷 3886-3902页

作者： Nancy K Arteaga-Resendiz Gerardo E Rodea Rosa María Ribas-Aparicio Alma L Olivares-Cervantes Juan Arturo Castelán-Vega Joséde Jesús Olivares-Trejo Sandra Mendoza-Elizalde Edgar O López-Villegas Christian Colín Pamela Aguilar-Rodea Alfonso Reyes-López Marcela Salazar García Norma Velázquez-Guadarrama laboratorio de Investigación en Enfermedades Infecciosas Hospital Infantil de México Federico GómezMexico City 06720Mexico Posgrado en Biomedicina y Biotecnología Molecular Laboratorio de Producción y Control de BiológicosEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico laboratorio de Adquisición de Hierro Universidad Autónoma de la Ciudad MéxicoPosgrado Ciencias GenómicaMexico City 03100Mexico laboratorio Central de Microscopía Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Centro de estudios económicos y sociales en salud Hospital Infantil de México Federico GómezMexico City 06720Mexico laboratorio de Investigación en biología del desarrollo y Teratogénesis Experimental Hospital Infantil de México Federico GómezMexico City 06720Mexico

BACKGROUND The high prevalence and persistence of Helicobacter pylori(H. pylori) infection, as well as the diversity of pathologies related to it, suggest that the virulence factors used by this microorganism are varied. Moreover, as its proteome contains 340hypothetical proteins, it is important to investigate them to completely understand the mechanisms of its virulence and survival. We have previously reported that the hypothetical protein HP0953 is overexpressed during the first hours of adhesion to inert surfaces, under stress conditions, suggesting its role in the environmental survival of this bacterium and perhaps as a virulence *** To investigate the expression and localization of HP0953 during adhesion to an inert surface and against gastric(AGS) *** Expression analysis was performed for HP0953 during H. pylori adhesion. HP0953 expression at 0,3, 12, 24, and 48 h was evaluated and compared using the Kruskal-Wallis equality-of-populations rank test. Recombinant protein was produced and used to obtain polyclonal antibodies for immunolocalization. Immunogold technique was performed on bacterial sections during adherence to inert surfaces and AGS cells, which was analyzed by transmission electron microscopy. HP0953 protein sequence was analyzed to predict the presence of a signal peptide and transmembrane helices, both provided by the ExPASy platform, and using the GLYCOPP platform for glycosylation sites. Different programs, via, I-TASSER, RaptorX, and HHalign-Kbest, were used to perform three-dimensional *** HP0953 exhibited its maximum expression at 12 h of infection in gastric epithelium *** technique revealed HP0953 localization in the cytoplasm and accumulation in some peripheral areas of the bacterial body, with greater expression when it is close to AGS *** analysis revealed the presence of a signal peptide that interacts with the transmembrane region and then allows the release of the protein

关键词： Hypothetical protein HP0953 Adherence Helicobacter pylori Glycocalyx Virulence factor Persistence

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Helicobacter pylori-induced inflammation and epigenetic changes during gastric carcinogenesis

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World Journal of Gastroenterology 2015年第45期21卷 12742-12756页

作者： Manuel A Valenzuela Jimena Canales Alejandro H Corvalán Andrew FG Quest laboratorio de Comunicaciones Celulares Centro de Estudios Moleculares de la Célula Programa de Biología Celular y Molecular ICBM Facultad de Medicina Universidad de Chile Cellular Communication Laboratory Center for Molecular Studies of the Cell Advanced Center for Chronic Diseases School of Medicine Universidad de Chile UC-Centro de Investigación en Oncología Pontificia Universidad Católica de Chile departamento de Hematología-Oncología Facultad de Medicine Pontificia Universidad Católica de Chile

The sequence of events associated with the development of gastric cancer has been described as "the gastric precancerous cascade". This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori(H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the mostrelevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and mi RNAs in this context.

关键词： Helicobacter pylori Methylation Gastric cancer Epi

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Habitat use in eight populations of Sceloporus grammicus(Squamata:Phrynosomatidae)from the Mexican Plateau

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Integrative Zoology 2017年第3期12卷 198-210页

作者： Adrian LEYTE-MANRIQUE Uriel HERNÁNdeZ-SALINAS Aurelio RAMÍREZ-BAUTISTA Vicente MATA-SILVA Jonathon C.MARSHALL laboratorio de biología Instituto Tecnológico Superior de SalvatierraSalvatierraGuanajuatoMexico Instituto Politécnico Nacional CIIDIR Unidad DurangoSigma 119Fraccionamiento 20 de Noviembre IIDurangoDurango 34220México laboratorio de Ecología de Poblaciones Centro de Investigaciones BiológicasUniversidad Autónoma del Estado de HidalgoKm 4.5 carretera Pachuca-Tulancingo42184Mineral de la ReformaHidalgoMexico department of biological Sciences The University of Texas at El PasoEl PasoTexasUSA department of Zoology Weber State University1415 Edvalson StreetOgdenUtahUSA

Studies on habitat use have often helped explain observed variation in morphology,behavior and reproductive characteristics among populations within a single *** we analyze morphological and ecological characteristics of individuals from the Sceloporus grammicus species complex from 7 different localities(CER,El Cerezo;PAC,Pachuca;HUI,Huichapan;EZA,Emiliano Zapata;SMR,San Miguel Regla;LMJ,La Mojonera;and LMZ,La Manzana)in the state of Hidalgo,and one locality(Cahuacán)in the State of Mexico.A canonical correspondence analysis(CCA)showed that females from PAC,EZA,LMZ,HUI,SMR and CAH populations use similar microhabitats characterized mostly by bare soil,in females from LMJ and CER use microhabitats characterized primarily by vegetation and *** were observed using 12 different types of *** regard to perch height use,the CCA showed that females from PAC,LMJ,LMZ,SMR,CER and CAH populations were correlated with height to nearest perch(HNP),in the rest of the females were not related to any perch use *** contrast,the CCA showed that males from PAC,LMJ and CAH were characterized by microhabitats with higher vegetal coverage,while males from LMZ and CER used microhabitats composed of bare soil,but males from HUI and SMR populations used microhabitats composed chiefly of bare soil and *** respect to perch height use,the CCA showed that males from PAC,LMJ,EZA and LMZ were correlated with distance to the nearest perch,but the rest of the males were not correlated with any perch use *** were observed in 9 different perch *** males were larger than the females in all morphological variables ***,in both sexes the snout-vent length is positively correlated with all morphological variables,and although both the slope and ordinate of the origin of all morphological variables were larger in males than females,the analysis of covariance indicated that there is no increase in the morphological variables with inc

关键词： canonical correspondence analyses habitat use morphology populations Sceloporus grammicus

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Unraveling the morphological patterns of a subantarctic eelpout:a geometric morphometric approach

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Integrative Zoology 2023年第2期18卷 372-384页

作者： Fernanda S.ORREGO Mathias HÜNE Hugo A.BENÍTEZ Mauricio F.LANDAETA laboratorio de Ictiología e Interacciones Biofísicas(LABITI) Instituto de BiologíaFacultad de CienciasUniversidad de ValparaísoValparaísoChile Centro de Investigación para la Conservación de los Ecosistemas Australes(ICEA) Punta ArenasChile laboratorio de Ecología y Morfometría Evolutiva Centro de Investigación de Estudios Avanzados del MauleUniversidad Católica del MauleTalcaChile Centro de Observación Marino para Estudios de Riesgos del Ambiente Costero(COSTA-R) Universidad de ValparaísoViña del MarChile Millennium Nucleus for Ecology and Conservation of Temperate Mesophotic Reef Ecosystems(NUTME) Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems(BASE) SantiagoChile

Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they ***,for marine species inhabiting contrasting aquatic conditions,it is expected toﬁnd covari-ation between the shape and its spatial *** studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps(4.5–22.5 cm TL)across its latitudinal distribution in South Paciﬁc(45°S–55°S).Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital *** was size variation across the sampled populations,but that size does not have a clear latitudinal *** 8%of the shape variation relates to this size variation(allometry),represented by a decrease in the relative size of the eye,and a depression of the posterior margin of the *** were spatial differences in the shape of the head,but these differences were probably caused by allometric ***,2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its *** study shows that the morphology of marineﬁsh with a shallow distribution varies across distances of hundreds of kilometers(i.e.,phenotypic modulation).

关键词： Austrolycus depressiceps geometric morphometrics morphology phenotype spatial distribution

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