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Presenilin mutations and their impact on neuronal differentiation in Alzheimer’s disease

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Neural Regeneration Research 2022年第1期17卷 31-37页

作者： Mercedes A.Hernández-Sapiéns Edwin E.Reza-Zaldívar Ana L.Márquez-Aguirre Ulises Gómez-Pinedo Jorge Matias-Guiu Ricardo R.Cevallos Juan C.Mateos-Díaz v.ctor J.Sánchez-González Alejandro A.Canales-Aguirre Unidad de Evaluación Preclínica Unidad de Biotecnología Médica y FarmacéuticaCentro de Investigación y Asistencia en Tecnología y Diseño del Estado de JaliscoGuadalajaraMéxico Instituto de Neurociencias IdISSCHospital Clínico San CarlosMadridEspaña Biochemistry and Molecular Genetics Department University of AlabamaBirminghamAlabama Unidad de Biotecnología Industrial Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de JaliscoGuadalajaraMéxico Centro Universitario de los Altos Universidad de GuadalajaraGuadalajaraMéxico

The presenilin genes(PSEN1 and PSEN2)are mainly responsible for causing early-onset familial Alzheimer’s disease,harboring~300 causative mutations,and representing~90%of all mutations associated with a very aggressive disease *** 1 is the catalytic core of theγ-secretase complex that conducts the intramembranous proteolytic excision of multiple transmembrane proteins like the amyloid precursor protein,Notch-1,N-and E-cadherin,LRP,Syndecan,Delta,Jagged,CD44,ErbB4,and *** 1 plays an essential role in neural progenitor maintenance,neurogenesis,neurite outgrowth,synaptic function,neuronal function,myelination,and ***,an imbalance caused by mutations in presenilin 1/γ-secretase might cause aberrant signaling,synaptic dysfunction,memory impairment,and increased Aβ42/Aβ40 ratio,contributing to neurodegeneration during the initial stages of Alzheimer’s disease *** review focuses on the neuronal differentiation dysregulation mediated by PSEN1 mutations in Alzheimer’s ***,we emphasize the importance of Alzheimer’s disease-induced pluripotent stem cells models in analyzing PSEN1 mutations implication over the early stages of the Alzheimer’s disease pathogenesis throughout neuronal differentiation impairment.

关键词： familial Alzheimer’s disease familial Alzheimer’s disease-induced pluripotent stem cells models induced pluripotent stem cells neurogenesis neuronal differentiation Notch presenilin 1 PSEN1 mutations γ-secretase complex

Gas Chromatography-Mass Spectrometry Study from the Leaves Fractions Obtained of <i>vernonanthura patens</i>(Kunth) H. Rob

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International Journal of Organic Chemistry 2013年第2期3卷 105-109页

作者： Patricia Manzano Santana Migdalia Miranda Juan Abreu Payrol Mario Silva v.ctor Hernández Esther Peralta Escuela Superior Politecnica de Litoral (ESPOL) Prosperina Campus Guayaquil Ecuador Institute of Food and Drugs University of Havana Havana Cuba School of Natural Sciences and Oceanography University of Concepción Concepción Chile

Preliminary phytochemical study of methanol extracts from vernonanthura patens’s leaves located in Marcabelí (El Oro province), Ecuador. The methodology consisted of chromatographic column separations with increasing polarity solvents and the analysis of fractions by Gas Chromatography-Mass Spectrometry coupled system (GC-MS). The structure of 53 compounds was proposed. Analyzed v. patens species showed the presence of terpene and aliphatic hydrocarbons, free fatty acids and their methyl and ethyl esters, oxygen sesqui, triterpenoids and sugars. For ecuadorian species, there are no records of chemical studies.

关键词： vernonanthura patens Phytochemical Study Gas Chromatographic-Mass Spectrometry Analysis

Effects of Plant Extracts and Beauveria bassiana on the Activity of Defense-Related Enzymes in Solanum lycopersicum *** Interaction with Fusarium oxysporum ***

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Phyton-International Journal of Experimental Botany 2023年第9期92卷 2503-2518页

作者： JoséAdrian Perez-Robles Carlos Alberto Lecona-Guzmán v.ctor Manuel Ruíz-valdiviezo Joaquín Adolfo Montes-Molina Laboratorio de Biotecnología vegetal Tecnológico Nacional de MexicoCampus Tuxtla GutiérrezTuxtla Gutiérrez29050Mexico

The objective to this work was to evaluate the enzymatic activity in the culture of Solanum lycopersicum *** with Fusarium oxysporum after the combined application of Beauveria bassiana and plant *** lycopersicum plantlets were transplanted 15 days after the *** days after transplanting,Beauveria bassiana spores were applied at a concentration of 1×10^(7)spores mL^(−1)onto soil(along with ***(N)and ***(H)leaf extracts)where *** plants were *** days after transplanting,spores of *** strain were applied at a concentration of 1×10^(6)spores mL^(−1)to soil where *** plants were *** development of *** plants was monitored for 114 days,whereby a randomized complete block treatment design was used,the roots of the plants were crushed with liquid nitrogen,after which Uv/vIS spectrophotometry was used to determine protein concentration,as well as the activity ofβ-1,3-glucanases,peroxidases(POX,EC1.***.1.7),catalase and *** treatments combining *** and *** and *** extracts,had a significant difference in enzymatic activity levels,thus contributing to better defense mechanisms and a greater protection to *** plants in the presence of *** application of *** and plant extracts to the ground mitigated damage caused by *** on *** plants.

关键词： Glucanases chitinases peroxidases catalase defense mechanisms

Microstructure and Properties Characterization of WC-Co-Cr Thermal Spray Coatings

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Journal of Minerals and Materials Characterization and Engineering 2018年第4期6卷 482-497页

作者： Karla Ofelia Méndez-Medrano Cecilio Jesús Martínez-González Francisco Alvarado-Hernández Omar Jiménez v.ctor Hugo Baltazar-Hernández Haideé Ruiz-Luna Unidad Académica de Ingeniería Universidad Autónoma de Zacatecas Zacatecas México CUCEI Universidad de Guadalajara Jalisco México Unidad Académica de Ingeniería CONACYT-Universidad Autónoma de Zacatecas Zacatecas México

WC-Co-Cr coatings are widely employed due to their improved wear resistance and mechanical properties, however, the properties and performance of these coatings are compromised by the processing parameters of each spraying technique. Therefore, this study is aimed to evaluate and determine the effect of the deposition parameters on the properties and microstructural characteristics of WC-Co-Cr coatings using a more economical thermal spray technique. In particular, the influence of flame spray parameters on the microstructure, crystal structure, hardness, and sliding wear resistance of WC- Co-Cr coatings was examined. Two parameters were considered: Type of flame (reducing, neutral and oxidizing), and the spray torch nozzle exit area. Results indicated that WC particles undergo considerable degree of decarburization and dissolution during spraying, showing substantial amounts of W2C, W, and Co3W3C, for all the considered conditions. However, the extent of phase transformation depended largely on the flame chemistry. The microstructure of the coatings was mainly affected by the spray nozzle. Regarding the sliding wear behavior, the coatings with uniform distribution of hard particles provided the best wear resistance. The decomposition of WC into W2C phase seems to have meaningless significance in the mass loss, nevertheless, the WC phase transformation to metallic tungsten and η-phase (Co3W3C) produce higher wear rates due to deficiency of carbide particles and embrittlement of the binder phase which induces cracking and delamination of the splats.

关键词： WC-Co-Cr Thermal Spray Coating X-Ray Phase Content Microstructure Flame

Diversity of Saxicolous Lichens along an Aridity Gradient in Central México

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Phyton-International Journal of Experimental Botany 2022年第4期91卷 827-840页

作者： JoséCarmen Soto-Correa Abraham Saldaña-vega v.ctor Hugo Cambrón-Sandoval Laura Concostrina-Zubiri Mariela Gómez-Romero Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroQuerétaro73230México Departamento de Biología y Geología Física y Química Inorgánica Tulipán s/nUniversidad Rey Juan CarlosMóstolesMadrid28933España Cátedra CONACYT–Facultad de Biología Universidad Michoacana de San Nicolás de HidalgoMoreliaMichoacán58030México

Lichens are symbiotic organisms that comprise a fungus and a photosynthetic partner wich are recognized as a good indicator of climate ***,our understanding of how aridity affects the diversity of saxicolous lichens in drylands is still *** evaluate the relationship between saxicolous lichen diversity and aridity in a central México dryland,a geographical transect was established of 100 km to build an aridity gradient in the semiarid zone of the State of Querétaro,Mexico,comprising ten sampling sites with a 10 km *** richness,abundance and diversity of soil lichen species were recorded using two sampling methods:the quadrat-intercept and the line-intercept method,to compare their performance in assessing soil lichen diversity in *** number of species and Shannon diversity of saxicolous lichens were higher at intermediate values of the aridity index(AI=0.10-0.34).Quadrat intercept and point intercept methods gave quite similar results,which means that the selected method does not influence the results in a significant *** study confirms the role of saxicolous lichens as climate change indicators and reveals the importance of the sampling method selection in the evaluation of different parameters of soil lichen diversity in drylands.

关键词： Climate change drylands ecological indicators environmental stress precipitation temperature

Decreased concentrating capacity in children with febrile urinary tract infection and normal 99mTc-dimercaptosuccinic acid scan:does medullonephritis exist?

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World Journal of Pediatrics 2014年第2期10卷 133-137页

作者： v.ctor García-Nieto Silvia González-Cerrato María Isabel Luis-Yanes Margarita Monge-Zamorano Beatriz Reyes-Millán Pediatric Nephrology Section "Nuestra Senra de la Candelaria"University HospitalSanta Cruz de TenerifeCanary IslandsSpain

Background:Although 99mTc-dimercaptosuccinic acid(DMSA)scan is considered the gold standard for the diagnosis of acute pyelonephritis(AP),sometimes it produces false results in children with clinical features of *** are no studies on the comparison of the sensitivity of DMSA and concentrating capacity ***:Eighty-fi ve infants with AP of less than one year old were studied to evaluate whether they had real AP or *** were compared between infants with an abnormal(group A,n=64)and those with a normal DMSA scan(group B,n=21)respectively.A DDAvP test was performed for each ***:All the infants in both groups presented a high level of C-reactive protein and fever(≥38oC).There were no differences in clinical and analytical variables except C-reactive protein level in the two *** groups exhibited a low urinary osmolality(87.5%in the group A vs.85.7%in the group B).The patients with normal DMSA and decreased concentrating capacity have some renal parenchymal damage and not only a lower urinary *** the infants with an abnormal DMSA scan,33.9%showed renal scars after 6-12 *** infant with a normal DMSA scan showed *** biochemical variables in both groups of infants were not related to vesicoureteral refl ***:Infants with AP,normal DMSA scan and low concentrating capacity may be characterized by a localized infection in the medulla(medullonephritis)or by a false negative DMSA scan.

关键词： concentrating capacity infants pyelonephritis urinary tract infection

Chitosan conduits enriched with fibrin-collagen hydrogel with or without adipose-derived mesenchymal stem cells for the repair of 15-mm-long sciatic nerve defect

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Neural Regeneration Research 2023年第6期18卷 1378-1385页

作者： Marwa El Soury óscar Darío García-García Isabella Tarulli Jesús Chato-Astrain Isabelle Perroteau Stefano Geuna Stefania Raimondo Giovanna Gambarotia v.ctor Carriel Department of Clinical and Biological Sciences University of TorinoTorinoItaly Neuroscience Institute Cavalieri Ottolenghi University of TorinoTorinoItaly Department of Histology Tissue Engineering GroupUniversity of GranadaGranadaSpain Instituto de Investigacion Biosanitaria Ibs.GRANADAGranadaSpain

Hollow conduits of natural or synthetic origins have shown acceptable regeneration results in short nerve gap repair;however,results are still not comparable with the current gold standard technique“autografts”.Hollow conduits do not provide a successful regeneration outcome when it comes to critical nerve gap *** the lumen of conduits with different extracellular materials and cells could provide a better biomimicry of the natural nerve regenerating environment and is expected to ameliorate the conduit *** this study,we evaluated nerve regeneration in vivo using hollow chitosan conduits or conduits enriched with fibrin-collagen hydrogels alone or with the further addition of adipose-derived mesenchymal stem cells in a 15 mm rat sciatic nerve transection *** changes in the hydrogel consistency and structural stability in vivo led to a failure of nerve regeneration after 15 ***,the molecular assessment in the early regeneration phase(7,14,and 28 days)has shown an upregulation of useful regenerative genes in hydrogel enriched conduits compared with the hollow *** composed of fibrin-collagen were able to upregulate the expression of soluble NRG1,a growth factor that plays an important role in Schwann cell *** further enrichment with adipose-derived mesenchymal stem cells has led to the upregulation of other important genes such as ErbB2,vEGF-A,BDNF,c-Jun,and ATF3.

关键词： adipose-derived stem cells chitosan conduit fibrin and collagen hydrogel nerve regeneration nerve repair neuregulin 1 peripheral nerve sciatic nerve

Kinetic Rates of the Fischer Tropsch Synthesis on a Co/Nb_2O_5 Catalyst

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Journal of Natural Gas Chemistry 2006年第4期15卷 307-312页

作者： v.ctor R.Ahón Paulo L.C.Lage Carlos D.D.de Souza Fabiana M.Mendes Martin Schmal Federal University of Rio de Janeiro Programa de Engenharia Química COPPE/UFRJ C.P.6850221941-972Rio de JaneiroRJBrazil

The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions （T=543 K, P=2.1 MPa） and under different conditions of several H2/CO feed molar ratio （0.49-4.79）, space velocities （0.2-3.8 h^-1）, mass of catalyst （0.3-1.5 g）, and CO conversion （10%-29%）. Synthesis gas conversion was measured and data were reduced to estimate the kinetic parameters for different Langmuir-Hinshelwood rate expressions. Differential and integral reactor models were used for the nonlinear regression of kinetics parameters. One of the rate equations could well explain the data. The hydrocarbon product distributions that were experimentally determined exhibited an unusual behavior, and a possible explanation was discussed.

关键词： Fischer-Tropsch natural gas kinetics selectivity

Theoretical Evaluation of Both Unknown Substrate Concentrations and Enzyme Kinetic Constants of Metabolic Cycles

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Journal of Biomedical Science and Engineering 2015年第8期8卷 479-489页

作者： Antonio Sillero v.ctor García-Herrero Departamento de Bioquímica Facultad de Medicina Instituto de Investigaciones Biomédicas Alberto Sols UAM/CSIC Madrid Spain

A formula has been deduced, and named as 2ESKv, relating the concentration of two consecutive substrates of a metabolic cycle with the kinetic constants of the two enzymes involved in their synthesis and degradation. After application of formula 2ESKv to consecutive pairs of substrates and enzymes, a system of interrelated equations was obtained allowing a great variety of theoretical postulates to calculate, back and forth: bunches of unknown enzyme kinetic constants and substrate concentrations, from complementary sets of known data. This vision of a metabolic cycle is of partial application to irreversible pathways and can be useful for modeling and understanding of metabolomics data. To our knowledge, the formula 2ESKv is here described for the first time.

关键词： Metabolic Cycles Evaluation Substrates Evaluation Enzymes Constants Differential Equations Mathematica