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Wnt signaling in midbrain dopaminerglc neuron development and regenerative medicine for Parkinson＇s disease

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Journal of molecular Cell Biology 2014年第1期8卷 42-53页

作者： Ernest arenas Laboratory of molecular Neurobiology Department of Medical Biochemistry and Biophysics Center of Developmental Biology for Regenerative MedicineKarolinska Institute Scheelevag 2 17 117 Stockholm Sweden

Wnts are a highly conserved family of Upid-modified glycoproteins that work as morphogens to activate several signaling pathways, leading to remodeling of the cytoskeleton and the regulation of gene transcription. Wnt signaling regulates multiple cellular functions and cell systems, including the development and maintenance of midbrain dopaminergic （m DA） neurons. These neurons are of consid- erable interest for regenerative medicine because their degeneration results in Parkinson＇s disease （PD）. This review focuses on new advances in understanding key functions of Wnts in mDA neuron development and using novel tools to regulate Wnt signaling in re- generative medicine for PD. Particularly, recent reports indicate that appropriate levels of Wnt signaling are essential to improve the quantity and quality of stem ceil- or reprogrammed ceU-derived mDA neurons to be used in drug discovery and cell replacement therapy for PD.

关键词： Wntl Wnt5a sFRP stem cells transplantation reprogramming small molecules

Coupling textural and stable-isotope variations in fluvial stromatolites:Comparison of Pleistocene and recent records in NE Spain

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Journal of Palaeogeography 2019年第2期8卷 150-169页

作者： C.arenas m.C.Osácar L.Auqué C.Sancho Department of Earth Sciences University of Zaragoza Geotransfer Group and Institute for Research on Environmental Sciences of Aragón(IUCA)

Textural and stable isotopic features of two middle Pleistocene fluvial stromatolite profiles are compared to a recent stromatolite,both formed in the River Piedra system(NE Spain),to test the reliability of climatic,hydrologic and depositional information derived from ancient *** Pleistocene stromatolites formed in a multi-domed,highly-inclined *** recent stromatolite also formed in a highly-inclined cascade of the River Piedra,the sedimentary conditions of which were periodically examined between the years 2000 and *** Pleistocene stromatolites are formed of an alternation of 1) thin large-crystal laminae(type A),with elongated crystals up to 1 mm long,and 2) thick small-crystal laminae(type B),consisting of cyanobacterial fan-and bushshaped *** textural and isotopic comparison with the recent stromatolite shows that each A–B couplet corresponds to one *** type-A laminae are comparable to the macrocrystalline laminae that occur in the cool-period deposits of the recent stromatolite,and the type-B laminae are comparable to the warm-period deposits of the recent *** temperatures(Tw),calculated from δ^(18)O_(calcite) and present measures of δ^(18)O_(water),were similar in the Pleistocene and recent specimens,and close to the measured river ***,the Pleistocene stromatolites formed not far from isotopic equilibrium,as did the recent *** Pleistocene δ^(18) O_(calcite) biannual oscillation is wider in amplitude than in the recent stromatolite,which suggests larger differences in Tw through the year in the Pleistocene than at *** Pleistocene δ^(13)C_(calcite) does not show any pattern;and the values are slightly higher than the recent *** co-evolution of δ^(18)O and δ^(13)C is parallel in the Pleistocene stromatolites,matching the recent stromatolite *** results and their comparison with other ancient examples prove that textural and isotopic features in ancient stromatolites

关键词： Tufa Recent and ancient stromatolites Stable isotopes Biotic and abiotic laminae Intra-annual and inter-annual water temperature variations

Frontier of the Paleo-Tethys Ocean in the western mediterranean:Isotopic(Sm-Nd)constraints on sources of Devonian units from menorca Island

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Geoscience Frontiers 2024年第5期15卷 323-338页

作者： Ricardo arenas Jose m.Fuenlabrada Cristian Timoner Rubén Díez Fernández Esther Rojo-Pérez Departamento de mineralogía y Petrología and Instituto de Geociencias(UCm CSIC)Universidad ComplutenseMadridSpain Unidad de Geocronología(CAI de Ciencias de la Tierra y Arqueometría) Universidad ComplutenseMadridSpain Bayerisches Geoinstitut University of BayreuthBayreuthGermany Instituto Geológico y minero de España–CSIC SalamancaSpain

The c.1000-m-thick pre-orogenic Devonian mainly metapelitic sequence of North menorca Island shows a fairly complete stratigraphic *** rocks of this sequence indicate gradually increasing deeper marine conditions of sedimentation towards its uppermost ***,the obtained sedimentary characteristics resemble those related to a deep and narrow basin-associated *** sills of Ti-augite-bearing alkaline gabbros occur within the Devonian *** intensity of Variscan deformation increases downwards through the *** to the characteristics of the Devonian sequence and its location within the Variscan Orogen,a correlation with similar units located in the southern sectors of the Central Iberian Zone(Iberian massif)is *** Devonian metapelitic rocks have geochemical characteristics suggesting that they represent moderately recycled mature siliciclastic sediments,generated from erosion of distant source areas belonging to an upper continental *** relatively narrow range of variation observed in initial^(143)Nd/^(144)Nd ratios supports a similar source for the menorcan slates(0.51165–0.51182).However,a marked trend is observed in these isotope ratios,from lower values at the base of the stratigraphic column(minimum value of 0.511941)to higher values at the top(maximum value of 0.512131).The^(147)Sm/^(144)Nd ratios vary between 0.1074 and 0.1238,within the range defined for siliciclastic rocks with felsic crustal *** Nd model ages define a narrow range between 1496 ma and 1754 ma(Late Paleoproterozoic–Early mesoproterozoic),and they are consistently younger *** data rule out a provenance from the erosion of the West Africa Craton,as they are more compatible with a provenance from regions located in the Trans-Saharan Belt or Sahara *** characteristics of the menorcan Devonian sequence are compatible with its deposition in a narrow and deep peri-Gondwanan transtensional basin,gener

关键词： Western Paleo-Tethys frontiers menorca Island Sm-Nd isotopic constraints Devonian sequence provenance in Gondwana

Genome-Wide Survey and Evolutionary Analysis of Trypsin Proteases in Apicomplexan Parasites

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Genomics, Proteomics & Bioinformatics 2010年第2期8卷 103-112页

作者： Aylan Farid arenas Juan Felipe Osorio-méndez Andres Julian Gutierrez Jorge E. Gomez-marin Grupo de Parasitología molecular (GEPAmOL) Centro de Investigaciones BiomédicasUniversidad del QuindíoArmeniaColombia

Apicomplexa are an extremely diverse group of unicellular organisms that infect humans and other animals. Despite the great advances in combating infectious diseases over the past century, these parasites still have a tremendous social and economic burden on human societies, particularly in tropical and subtropical regions of the world. Proteases from apicomplexa have been characterized at the molecular and cellular levels, and central roles have been proposed for proteases in diverse processes. In this work, 16 new genes encoding for trypsin proteases are identified in 8 apicomplexan genomes by a genome-wide survey. Phylogenetic analysis suggests that these genes were gained through both intracellutar gene transfer and vertical gene transfer. Identification, characterization and understanding of the evolutionary origin of protease-mediated processes are crucial to increase the knowledge and improve the strategies for the development of novel chemotherapeutic agents and vaccines.

关键词： Apicomplexa trypsin endosymbiotic gene transfer

Stable NiO-CeO_(2) nanoparticles with improved carbon resistance for methane dry reforming

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Journal of Rare Earths 2022年第1期40卷 57-62页

作者： Andrea Cárdenas-arenas Esther Bailón-García Dolores Lozano-Castelló Patrick Da Costa Agustín Bueno-López Department of Inorganic Chemistry University of AlicanteCarretera de San Vicente s/nE03080AlicanteSpain Sorbonne Universite Institut Jean Le Rond d'AlembertCNRS UMR 71902 place de la gare de ceinture78210Saint Cyr L'EcoleFrance

High surface area mixed oxide 8.7%NiO-CeO_(2) nanoparticles(122 m2/g;6-7 nm)were prepared using a reversed microemulsion method,and were tested for dry methane reforming(DRm).The catalytic activity of these nanoparticles remains stable under the severe conditions of DRm(700℃),and they show better carbon resistance than conventional NiO-CeO_(2) catalysts prepared without control of the *** activity and selectivity of nanoparticles and reference catalyst are similar,but nanoparticles reduce the accumulation of carbon by 63%during the DRm tests,which is a key feature for this *** and H_(2)-TPR suggest that the improved carbon resistance of the nanoparticles is due to the better interaction and cooperation between NiO and CeO_(2) mixed *** nanoparticles,the participation of cerium cations in the redox processes taking place during DRm stabilizes cationic species of *** the contrary,the catalyst prepared without control of the size suffers segregation of Ni during DRm reaction,and segregated Ni explains the higher catalytic formation of carbon.

关键词： methane dry reforming Nickel Ceria Nanoparticle Rare earths

Cell Death mechanisms Induced by Cytotoxic Lymphocytes

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Cellular & molecular Immunology 2009年第1期6卷 15-25页

作者： Chávez-Galán L arenas-Del Angel mC Zenteno E Chávez R Lascurain R Departamento de Bioquímica Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas" Departamento de Bioquímica Facultad de MedicinaUniversidad Nacional Autónoma de México

One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer （NK） cells and CD8^＋T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor （TNF） and TNF receptor pathway. We discussed three models of possible molecular interaction between lytic molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis. Cellular ＆ molecular Immunology.

关键词： apoptosis cytotoxic cell granule-dependent exocytosis FasL TNF

An imbalance between innate and adaptive immune cells at the maternal-fetal interface occurs prior to endotoxin-induced preterm birth

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Cellular & molecular Immunology 2016年第4期13卷 462-473页

作者： marcia arenas-Hernandez Roberto Romero Derek St Louis Sonia S Hassan Emily B Kaye Nardhy Gomez-Lopez Department of Obstetrics & Gynecology Wayne State University School of Medicine Detroit Michigan USA perinatology Research Branch Program for Perinatal Research and Obstetrics Division of Intramural Research Eunice Kennedy ShriverNational Institute of Child l~ealth and Human DevelopmentNIC.HD/NIHDHHS Bethesda Maryland and Detroit Michigan USA Departme.nt of Obstetrics and Gynecology University of M chigan Ann ArborMichigan USA Department of Epidemiology and Biostatistics Michigan State University East Lansing Michigan USA Department of molecular Obstetrics and Genetics Wayne State University Detroit Michigan USA Department of ImmunoLogy & microbioLogy Wayne State University School of Medicine Detroit Michigan USA

Preterm birth （PTB） is the leading cause of neonatal morbidity and mortality worldwide. A transition from an anti-inflammatory state to a pro-inflammatory state in the mother and at the maternal-fetal interface has been implicated in the pathophysiology of microbial-induced preterm labor. However, it is unclear which immune cells mediate this transition. We hypothesized that an imbalance between innate and adaptive immune cells at the maternal-fetal interface will occur prior to microbial-induced preterm labor. Using an established murine model of endotoxin-induced PTB, our results demonstrate that prior to delivery there is a reduction of CD4 ＋ regulatory T cells （Tregs） in the uterine tissues. This reduction is neither linked to a diminished number of Tregs in the spleen, nor to an impaired production of ILIO, CCL17, or CCL22 by the uterine tissues. Endotoxin administration to pregnant mice does not alter effector CD4＋ T cells at the maternal-fetal interface. However, it causes an imbalance between Tregs （CD4＋ and CD8＋）, effector CD8＋ T cells, and Th17 cells in the spleen. In addition, endotoxin administration to pregnant mice leads to an excessive production of CCL2, CCL3, CCL17, and CCL22 by the uterine tissues as well as abundant neutrophils. This imbalance in the uterine microenvironment is accompanied by scarce APC-like cells such as macrophages and mHC II ＋ neutrophils. Collectively, these results demonstrate that endotoxin administration to pregnant mice causes an imbalance between innate and adaptive immune cells at the maternal-fetal interface.

关键词： antigen-presenting cells effector T cells inflammation labor lipopolysaccharide macrophages microbial product neutrophils pregnancy preterm labor regulatory T cells

Evidence-based Rapid Review to Approach Diagnostic Test Research. A Veterinary Practitioners Opinion

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Veterinary Science Research 2021年第1期3卷 25-27页

作者： Julio A.arenas Jeff m.Perez Advanced Veterinary Centre Madinat Khalifa SouthDohaQatar

In animal research systematic reviews and meta-analysis have been playing an important role in improving the quality of evidence that professionals use ***,it is claimed that it is in its initial stage of *** veterinary medicine the heterogeneity in the evaluation of variables of exposure and response makes it difficult to gather the data results for a meta-analysis and evidence-based rapid reviews and other types of reviews can accelerate the way how we obtain this information and a problem-solving approach can be developed in the veterinary medicine field.

关键词： Evidence-based medicine Systematic review Rapid review meta-analysis

Hydrothermal synthesis of pyrrhotite(Fex-1S) nanoplates and their antibacterial, cytotoxic activity study

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Progress in Natural Science:materials International 2018年第4期28卷 447-455页

作者： Liliana Argueta-Figueroa Nayely Torres-Gómez René García-Contreras A.R.Vilchis-Nestor O.martínez-Alvarez L.S.Acosta-Torres m.C.arenas-Arrocena Laboratorio de Investigación Interdisciplinaria área de Nanoestructuras y Biomateriales Escuela Nacional de Estudios Superiores Unidad León Universidad Nacional Autónoma de México Centro Conjunto de Investigación en Química Sustentable (CCIQS) UEAMex-UNAM Departamento de Ingeniería en Energía Universidad Politécnica de Guanajuato

The aim of this study was to synthesize and characterize Fex-1S 2D-nanostructures with pyrrhotite phase,as well as to explore their biological(antibacterial and cytotoxic)properties,namely the expression of reactive oxygen species(ROS)in the exposure of cells and *** on hydrothermal synthesis,the characterization of asprepared 2D-nanostructures was performed by XRD,SEm,EDS,and TEm,in which the single-crystalline pyrrhotite phased Fex-1S nanoplate morphology was *** antibacterial activities of Fex-1S nanoplates against human pathogenic strains such as Staphylococcus aureus,Escherichia coli,and Enterococcus faecalis were *** inhibitory concentration(mIC)and minimum bactericidal concentration(mBC)were determined following the broth microdilution *** and expression of intracellular ROS of pyrrhotite nanoplates on Human Gingival Fibroblast(HGF),Human Pulp Cells(HPC)and Human Osteoblast(HBC)were *** viability was determined by the mTT *** experiments were performed of three independent experiments and data were analyzed by Kruskal-Wallis and mann-Whitney tests,also Pearson′s Correlation was *** nanoplates exhibited good bactericidal *** types of cells tested showed slight *** was found that intracellular ROS is produced when cells and bacteria tested are exposed to pyrrhotite nanoplates in presence of both air and peroxide *** production levels were higher in the bacteria than the cells exposed to these nanoplates.

关键词： Hydrothermal synthesis Iron sulfide nanoplates minimal inhibitory concentration Antibacterial effect Cytotoxicity assay