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Stage-Specific Changes on <i>Plasmodium yoelii yoelii </i>Following Treatment with <i>Hintonia latiflora</i>Stem Bark Extract and Phytochemical-Antioxidant Evaluation

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Pharmacology & Pharmacy 2017年第12期8卷 381-395页

作者： elba carrasco-ramírez Perla Y. López-Camacho Armando Zepeda-Rodríguez Patricia Bizarro-Nevares Filiberto Malagón-Gutiérrez Gustavo Basurto-Islas Norma Rivera-Fernández Laboratorio de Malariología Departamento de Microbiología y Parasitología Facultad de Medicina Universidad Nacional Autónoma de México CDMX México Departamento de Ciencias Naturales e Ingeniería Universidad Autónoma Metropolitana CDMX México Deparatmento de Biología Celular y Tisular Facultad de Medicina Universidad Nacional Autónoma de México CDMX México Departamento de Ingenierías Química Electrónica y Biomédica División de Ciencias e Ingeniería Universidad de Guanajuato Campus León Guanajuato México

Malaria endemic zones are mostly located on third world countries, where antimalarials are not easily found or patients cannot afford them, and in consequence, they must turn toward natural products or phytomedicines. In the present study, the effect of Hinotnia latiflora (Hl) methanolic stem bark extract (HlMeOHe) on the ultrastructure of the asexual intraerythrocytic stages of Plasmodium yoelii yoelii (Pyy) after a Peters’ four-day oral treatment was assessed by transmission electron microscopy (TEM), as well as the parasite development on blood smears, analyzed by light microscopy. Likewise, extract was subjected to qualitative tests adopting standard procedures for identification of phytoconstituents;its antioxidant activity was evaluated according to the method of Brand-Williams and by the radical cation decolorization assay. Results showed higher percentage of rings and lower percentage of trophozoites and schizonts in the treated animals, in comparison with those of the control groups, which demonstrated lower percentage of rings and trophozoites, and schizonts in higher number. Images of TEM showed in some treated parasites, mild parasite membranes, organelle swelling and ribosomal depletion. The phytochemical profile demonstrated that the extract contains alkaloids, tannis, steroids, terpenoids, flavonoids, phenolics and saponins. The obtained values of the half maximal inhibitory concentration (IC50) in μg/mL, for both antioxidant assays were of 423.83 and 202.95 respectively. It is concluded that HlMeOHe altered the development of the intraerythrocytic asexual stages and the ultrastructure of Pyy, and due to its phytochemical constituents, showed an in vitro antioxidant activity.

关键词： Hintonia latiflora Plasmodium yoelii yoelii Malaria Ultrastructural Changes Phytochemicals Antioxidant Natural Products

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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)

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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

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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

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Tropical ash(Fraxinus udhei)invading Andean forest remnants in Northern South America

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Ecological Processes 2018年第1期7卷 152-164页

作者： Kelly A.Saavedra-ramírez AndrésEtter Alberto ramírez Depa rtamento de Ecologia y Territoto Pontificia Universidad averianaBogotaColomba

Introduction:Exotic invasive species represent a major driver of the loss of biological diversity and services provided by ecosystems *** important cause of species becoming invasive is the development of commercial afforestation projects using fast-growing and adaptable exotic species,which may become invasive impacting natural *** tropical ash(Fraxinus uhdei),native to México,has been widely introduced to Colombia and other countries for timber,live fences,and urban *** is now common in many areas of the tropical mountains and has been observed expanding into native forests in *** study examined the invasion pattern and the demographic structure of tropical ash in remnant Andean forests in Colombia,to find out factors associated with the invasion *** analysis took into account biotic and physical factors:distance to propagule source,vegetation cover types,and understory and canopy ***:Although the reproductive strategy of the tropical ash is of“r”type with low survival rates,the results show evidence for an active process of invasion characterized by an aggregated distribution pattern dominated by seedlings and juvenile *** study shows the existence of an interaction between the distance to propagule source and the vegetation cover,which has an additive effect on the demographic structure of the ***:This study suggests an active invasion process by the exotic tree tropical ash into a remnant of sub-humid forests in the Andean *** results showed an expanding population process with a decreasing average age from propagule sources and mature reproductive individuals within the native forest,which bring new individuals that are colonizing new areas and advancing into the *** research points to the need for urgent plant intervention on two aspects:the use of the tropical ash and the management of the invasion process in native forests.

关键词： Andean forest Demographic structure Fraxinus uhdei Exotic species Plant biological invasions Invasion pattern

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Solution of the Center Problem for a Class of Polynomial Differential Systems

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1685-1696页

作者： Chang Jian Liu Jaume Llibre Rafael ramírez Valentín ramírez School of Mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Departament de Matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departament d’Enginyeria Informàtica i Matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the polynomial differential system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμandνare real numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous polynomial of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential system has a weak center at the origin if and only if after a convenient linear change of variable(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we prove the extension of this conjecture to any value ofνexcept for a finite set of values ofμ.

关键词： Center problem polynomial differential system

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Flight feather moult in Western Marsh Harriers during autumn migration

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Avian Research 2019年第1期10卷 30-35页

作者： Juan ramírez Michele Panuccio MEDRAPTORS(Mediterranean Raptor Migration Network) DSTA-Department of Earth and Environmental Sciences University of Pavia

Background:Most of long-distance migratory raptors suspend moult during migration but detailed information is patchy for most of the Palearctic *** aim of this research is to verify if active moulting in migrating Western Marsh Harriers occurs and to quantify the extent of moulting along the season focusing on primary ***:During a whole post-breeding migration at the Strait of Messina in Southern Italy,we gathered information about symmetrical flight feather moult from 221 adults by taking pictures of raptors passing at close ***:We found active moulting primaries during autumn migration in 48.4% of our *** differences on the extension and timing among sex classes were recorded during the season,with adult females showing a more advanced moult stage than adult ***:The finding that the extension of the suspended moult was already defined in migratory individuals might be explained as an adaptation to minimize the energy required for moulting during migration.

关键词： Migration Moult Primary feather Raptors Western Marsh Harrier

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Resveratrol as an inductor of autophagy: is there a unique pathway of activation?

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Neural Regeneration Research 2021年第1期16卷 101-103页

作者： Narayana Pineda-ramírez Penélope Aguilera Laboratorio de Patología Vascular Cerebral.Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez Ciudad de MéxicoMéxico

Autophagy is a process of cellular degradation for the removal of damaged components and eventual recycling of the resulting molecules that help to the maintenance of cellular *** this pathway,proteins with relatively long half-life and whole organelles(e.g.,mitochondria,peroxisomes,and ribosomes)are degraded in the cytoplasm for the continuous turnover of cellular structures to facilitate their ***,the beneficial effect of autophagy goes beyond cellular“cleaning”and resides to a large extent on its ability to recycle cell components back into the ***,autophagy is a fundamental mechanism to regulate cellular functions,including DNA repair,proliferation,differentiation,embryonic development,and the immune response.

关键词： homeostasis activation autophagy

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Modeling the Spike Response for Adaptive Fuzzy Spiking Neurons with Application to a Fuzzy XOR

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Computer Modeling in Engineering & Sciences 2018年第6期115卷 295-311页

作者： A.M.E.ramírez-Mendoza CONACYT Research Fellow–State University of Nuevo León(UANL for its acronym in Spanish) Mechanical and Electrical Engineering School(FIME for its acronym in Spanish)Center for Research and Innovation in Aeronautical Engineering(CIIIA for its acronym in Spanish)Carretera a Salinas Victoria km.2.3ApodacaNuevo LeónMéxico

A spike response model(SRM)based on the spikes generator circuit(SGC)of adaptive fuzzy spiking neurons(AFSNs)is *** SRM is simulated in MatlabTM *** proposed model is applied to a configuration of a fuzzy exclusive or(fuzzy XOR)operator,as an illustrative example.A description of the comparison of AFSNs with other similar methods is *** novel method of the AFSNs is used to determine the value of the weights or parameters of the fuzzy XOR,first with dynamic weights or self-tuning parameters that adapt continuously,then with fixed weights obtained after training,finally with fixed weights and a dynamic gain or self-tuning gain for a fine adjustment of amplitude.

关键词： Spike response model spikes generator circuit fuzzy XOR adaptive fuzzy spiking neuron learning algorithm fuzzy neuron self-tuning

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High Temperature Oxidation of a Work Roll Grade High-Chromium White Cast Iron

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Journal of Iron and Steel Research International 2013年第10期20卷 122-129页

作者： J H ramírez-ramírez R Colás N F Garza-Montes-de-Oca Faculty of Mechanical and Electrical Engineering Autonomous University of Nuevo Leon

High-chromium white cast iron is a common material for the manufacture of the work rolls used in the fin- ishing stands in hot strip mills. The high temperature oxidation behaviour of as-cast and heat-treated high-chromium white cast iron was studied by gravimetric means at 650 ℃ in atmospheres that included dry air and a mixture of dry air and water vapour. For both environmental and material conditions, the oxidation rate of the alloys was represen ted by parabolic trends and the oxidation phenomenon was more obvious when the samples were oxidised in water vapour. Water vapour also influenced the chemical composition of the oxides formed in the alloy and under this condi tion, the oxide scale formed on the alloy contained the oxides FeCr2O4 , （Fe,Cr）3O4 and （Fe,Cr）2 O3. In contrast, the alloys exposed to dry air conditions only experienced the formation of FeCr2O4 and （Fe,Cr）2O3. It was found that the presence of water vapour and the chromium content of the alloys increased the oxidation rate by a mechanism that involved chromium depletion of the oxide as a result of hydroxide formation. The differences observed in the oxi- dation behaviour of the alloy are discussed in terms of the composition of the oxidant atmosphere and the metallurgi cal condition of the specimens.

关键词： white cast iron oxidation water vapour work roll

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