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Ursane derivatives isolated from leaves of Hylocereus undatus inhibit glycation at multiple stages

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Chinese Journal of Natural Medicines 2018年第11期16卷 856-865页

作者： rosa.ma.tha.pérez-gutiérrez SUSANA GABRIELA Enriquez-Alvirde Research Laboratory of Natural products School of Chemical Engineering and Extractive Industries National Polytechnic Institute

The present study was designed to evaluate the therapeutic potential of bioactive compounds from chloroform extract of the leaves of Hylocereus undatus in the formation of advanced glycation end products(AGEs) in vitro. Bioactivity-guided fractionation of chloroform extract from Hylocereus undatus afforded two novel 12-ursen-type triterpenes, 3β, 16α, 23-trihydroxy-urs-12-en-28-oic acid(1) and 3β, 6β, 19α, 22α-tetrahydroxy-urs-12-en-28-oic acid(2), as well as four known triterpenes 2α, 3β, 23-tetrahydroxy-urs-11-en-28-oic acid(3), 3β-acetoxy-28-hydroxyolean-12-ene(4), 3β, 16α-dihidroxyolean-12-ene(5) and 3β-acetoxy-olean-12-ene(6). Our results revealed that triterpenes 1–3 were able to inhibit the formation of AGEs in all tested assays. The data indicated that the triterpenes had inhibitory activity at the múltiple stages of glycation and that there might be a high potential for decreasing protein oxidation and protein glycation that can enhance glycative stress in diabetic complications.

关键词： Hylocereus undatus Advanced glycation end product Triterpenes

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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Neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital Nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research Unit for Neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Impacts of pI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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Neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón pérez-Núñez maría Fernanda González Ana maría Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(pI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the pI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/pI3K/AKT/connexin 43,and Notch/pI3K/AKT *** targeting the inactivation of the pI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the pI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

Effect of logging on rodent scatter-hoarding dynamics in tropical forests:implications for plant recruitment

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Integrative Zoology 2011年第2期6卷 74-80页

作者： Gabriel gutiérrez-GRANADOS Department of Zoology Institute of BiologyNational Autonomous University of MexicoMexico DFMexico

The present study tested the hypothesis that logging affects the scatter-hoarding behavior of rodents,which,in turn,negatively affects the quantity and quality of pouteria campechiana(Sapotaceae)seed dispersal.A series of seed stations was established in logged and unlogged forests of ejido Senor,Yucatan peninsula,and comparisons were made between logged and unlogged forests in terms of:(i)seed removal;(ii)number of seeds hoarded;(iii)hoarding distance;and(iv)the number of recruits and the survival of hoarded *** number of both hoarded and removed seeds was significantly higher in unlogged ***,the mean distance of hoarding was greater in unlogged compared with logged *** recruitment and survival were present in both logged and unlogged sites,there were more surviving seedlings in unlogged *** data indicate that both the quantity and quality of seed dispersal are negatively affected by logging because of a change in the rodent scatter-hoarding *** changes suggest that plant-animal interactions are crucial to the understanding of the ecology and conservation of managed tropical forests.

关键词： Dasyprocta punctata seed caching timber extraction Yucatan peninsula

Identification of plant genes putatively involved in the perception of fungal ergosterol-squalene^∞

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Journal of Integrative plant Biology 2020年第7期62卷 927-947页

作者： Laura Lindo rosa E.Cardoza Alicia Lorenzana pedro A.Casquero Santiago gutiérrez Area of Microbiology University of LeónCampus of PonferradaPonferradaSpain University Group of Research in Engineering and Sustainable Agriculture University of LeónLeónSpain

Trichoderma biocontrol strains establish a complex network of interactions with plants,in which diverse fungal molecules are involved in the recognition of these fungi as nonpathogenic *** molecules act as microbial-associated molecular patterns that trigger plant *** studies have reported the im-portance of ergosterol produced by Trichoderma *** the ability of these fungi to induce plant growth and *** addition,squalene,a sterol biosynthetic inter-mediate,seems to play an important role in these ***,we analyzed the effect of different concentrations of ergosterol and squalene on tomato(Solanum lycopersicum)growth and on the transcription level of defense-and growth-related *** used an RNA-seq strategy to identify several tomato genesencoding predicted pattern recognition receptor proteins or WRKY transcription factors,both of which are puta-tively involved in the perception and response to ergo-sterol and ***,an analysis of Arabidopsis thaliana mutants lacking the genes homologous to these tomato candidates led to the identification of a WRKY40 transcription factor that negatively regulates salicylic acid-related genes and positively regulates ethylene-and jasmonate-related genes in the presence of ergosterol and squalene.

关键词： plant perception pattern

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri H.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen ma Jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of physics and Wuhan National High magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QpI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Surface properties of Fe_4N Compounds Layer on AISI 4340 Steel Modified by pulsed plasma Nitriding

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Journal of materials Science & Technology 2013年第3期29卷 287-290页

作者： J.C.Díaz-Guillén G.Vargas-gutiérrez E.E.Granda-gutiérrez J.S.Zamarripa-pia S.I.pérez-Aguilar J.Candelas-Ramírez L.lvarez-Contreras Centro de Investigacin en materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investigacin en materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investigacin y Estudios Avanzados del IpN Unidad SaltilloCarretera Saltillo Monterrey km 13Apdo.Postal 663C.P.25000 SaltilloCoahuilaMexico

In this work, the effect of nitriding current density on hardness, crystalline phase composition, layer thickness and corrosion rate of AlSl 4340 steel has been studied. X-ray diffraction analysis shows that thin layers formed during nitriding process are constituted of 7-Fe4N for samples processed between 1 and 2.5 ma/cm2. Thickness of nitrided layer increases proportionally to current density （0 μm for 0.5 ma/cm2 to 15 pm for 2.5 ma/cm2）. plasma nitriding increased the surface hardness from 300 HV50g for untreated sample, to around 800HV5og for nitrided samples at 1 ma/cm2. While the untreated samples exhibited a corrosion rate of 0.153 mm per year, the corrosion performance was improved up to 0.03 mm per year at current densities above 1 ma/cm2, which is about one fifth of the corrosion rate of the untreated sample.

关键词： plasma nitriding Current density Hardness Corrosion

A building energy models calibration methodology based on inverse modelling approach

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Building Simulation 2022年第11期15卷 1883-1898页

作者： Vicente gutiérrez González Carlos Fernández Bandera Installations construction and structuresSchool of ArchitectureUniversity of NavarraCampus UniversitarioPamplona31009NavarraSpain

Nowadays,building energy models(BEMs)are widely used,particularly in the assessment of energy consumption in buildings to address the potential savings that can be *** realisation of a dynamic energy model based on high-fidelity physics(white-box models)requires a tuning process to fit the model to reality,due to many uncertainties *** some research trends try to reduce this performance gap by modulating different types of experimental parameters such as:capacitances or *** Energyplus simulation software,in its latest versions,has implemented an object:HybridModel:Zone that calculates the infiltration and internal mass of buildings using an inverse modelling approach that employs only the measured indoor temperature data to invert the heat balance equation for the zone under *** main objective of this paper is to reduce the execution time and uncertainties in the development of quality energy models by generating a new calibration methodology that implements this *** uses,as a starting point,a research created by the authors of this study,which was empirically and comparatively validated against the energy models developed by the participants in Annex *** is also worth highlighting the empirical validation of the HybridModel:Zone object,since it was activated in all scenarios where its execution is possible:periods of seven days or more of free oscillation and periods in which the building is under *** findings are *** data generated with the new methodology,if compared with those produced by the baseline model,improve their resemblance to the real ones by 22.9%.While those of its predecessor did it by 15.6%.For this study,the two dwellings foreseen in Annex 58 of the IEA ECB project have been modelled and their real monitoring data have been used.

关键词： internal thermal mass energy simulation Energyplus inverse model Annex 58 infiltration