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Mitochondrial dysfunction as a target in spinal cord injury:intimate correlation between pathological processes and therapeutic approaches

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Neural Regeneration Research 2023年第10期18卷 2161-2166页

作者： julieta Schmidt héctor Ramiro Quintá Universidad de Buenos Aires CABAArgentina Laboratorio de Medicina Experimental“Dr.j.Toblli” Hospital AlemánCABAArgentina Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET CABAArgentina Rehabilitation Medicine Department University of MinnesotaTwin CitiesMINUSA

Traumatic spinal cord injuries interrupt the connection of all axonal projections with their neuronal targets below and above the lesion site. This interruption results in either temporary or permanent alterations in the locomotor, sensory, and autonomic functions. Damage in the spinal tissue prevents the re-growth of severed axons across the lesion and their reconnection with neuronal targets. Therefore, the absence of spontaneous repair leads to sustained impairment in voluntary control of movement below the injury. For decades, axonal regeneration and reconnection have been considered the opitome of spinal cord injury repair with the goal being the repair of the damaged long motor and sensory tracts in a complex process that involves:(1) resealing injured axons;(2) reconstructing the cytoskeletal structure inside axons;(3) re-establishing healthy growth cones;and(4) assembling axonal cargos. These biological processes require an efficient production of adenosine triphosphate, which is affected by mitochondrial dysfunction after spinal cord injury. From a pathological standpoint, during the secondary stage of spinal cord injury, mitochondrial homeostasis is disrupted, mainly in the distal segments of severed axons. This result in a reduction of adenosine triphosphate levels and subsequent inactivation of adenosine triphosphate-dependent ion pumps required for the regulation of ion concentrations and reuptake of neurotransmitters, such as glutamate. The consequences are calcium overload, reactive oxygen species formation, and excitotoxicity. These events are intimately related to the activation of necrotic and apoptotic cell death programs, and further exacerbate the secondary stage of the injury, being a hallmark of spinal cord injury. This is why restoring mitochondrial function during the early stage of secondary injury could represent a potentially effective therapeutic intervention to overcome the motor and sensory failure produced by spinal cord injury. This

关键词： adenosine triphosphate axonal regeneration creatine mitochondria dysfunction mitochondria spinal cord injury

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Diagnostic and therapeutic challenges of gastrointestinal angiodysplasias: A critical review and view points

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World journal of gastroenterology 2019年第21期25卷 2549-2564页

作者： Diego garcía-Compeán ángel N Del Cueto-Aguilera Alan R jiménez-Rodríguez josé A gonzález-gonzález héctor j maldonado-g.rza gastroenterology Service and Department of Internal Medicine Faculty of Medicine University Hospital "Dr. José E. González"Universidad Autónoma de Nuevo León

gastrointestinal angiodysplasias (gIADs), also called angioectasias, are the most frequent vascular lesions. Its precise prevalence is unknown since most of them are asymptomatic. however, the incidence may be increasing since gIADs affect individuals aged more than 60 years and population life expectancy is globally increasing worldwide. They are responsible of about 5% to 10% of all gastrointestinal bleeding (gIB) cases. Most gIADs are placed in small bowel, where are the cause of 50 to 60% of obscure gIB diagnosed with video capsule endoscopy. They may be the cause of fatal severe bleeding episodes;nevertheless, recurrent overt or occult bleeding episodes requiring repeated expensive treatments and disturbing patient’s quality-of-life are more frequently observed. Diagnosis and treatment of gIADs (particularly those placed in small bowel) are a great challenge due to insidious disease behavior, inaccessibility to affected sites and limitations of available diagnostic procedures. hemorrhagic causality out of the actively bleeding lesions detected by diagnostic procedures may be difficult to establish. No treatment guidelines are currently available, so there is a high variability in the management of these patients. In this review, the epidemiology and pathophysiology of gIADs and the status in the diagnosis and treatment, with special emphasis on small bowel angiodysplasias based on multiple publications, are critically discussed. In addition, a classification of gIADs based on their endoscopic characteristics is proposed. Finally, some aspects that need to be clarified in future research studies are highlighted.

关键词： Angiodysplasias Angioectasias Vascular malformations Epidemiology Pathogenesis Endoscopic treatment Somatostatin analogues

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Application of high silica zeolite ZSM-5 in a hybrid treatment process based on sequential adsorption and ozonation for VOCs elimination

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journal of Environmental Sciences 2016年第3期28卷 59-68页

作者： hicham Zaitan Marie hélène Manero héctor Valdés Laboratoire de Chirmie de la Matiere Condensee(LCMC) Faculte des Sciences et TechniquesUniversite Sidi Mohamed Ben AbdellahB.P.2202FesMaroc Universite de Toulouse INPTUPSLaboratoire de Genie Chimique4Allee Emile MonsoF-31030 ToulouseFrance CNRS Laboratoire de Genie ChimiqueF-31030 ToulouseFrance Laboratorio de Tecnologias Limpias(F.Ingenieria) Universidad Catolica de la Santisima ConcepcionAlonso de Ribera 2850ConcepcionChile

In this study,a hydrophobic synthetic zeolite,namely ZSM-5 is chosen as an adsorbent/catalyst for toluene *** results showed that toluene adsorption onto ZSM-5 was favourable,following a Langmuir adsorption isotherm ***-5 zeolite was regenerated using gaseous ozone at low *** toluene was oxidised,releasing mainly CO_2 and h_*** of oxidation by-products such as acetic acid and acetaldehyde were formed and remained adsorbed after the oxidativate regeneration with *** four successive cycles of adsorption/ozonation,the adsorption efficiency was not affected（92%-99%）.These results showed that volatile organic compound（VOC）removal by adsorption onto ZSM-5 zeolite followed by ozone regeneration could be used as a promising hybrid process for the control of VOC emissions in terms of efficiency.

关键词： Adsorption Ozone Toluene VOCs Zeolite

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Meckel's diverticulum diagnosis by video capsule endoscopy: A case report and review of literature

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World journal of Clinical Cases 2018年第14期6卷 791-799页

作者： Diego garcía-Compeán Alan R jiménez-Rodríguez Angel N Del Cueto-Aguilera gilberto herrera-Quinones josé A gonzález-gonzález héctor j maldonado-g.rza gastroenterology Service and Department of Internal Medicine Faculty of Medicine University Hospital "Dr. José E. González" Universidad Autónoma de Nuevo León Monterrey 64700 Nuevo León México

BACKgROUND Meckel’s diverticulum （MD） occurs predominantly in chil-dren and adolescents. It is rarely diagnosed in adults. Preoperative diagnosis is diffcult due to low sensitivity of the radiological imaging studies. The role of video capsule endoscopy （VCE） in the diagnosis of MD is unknown, and the endoscopic patterns are not defned. We will describe four of our cases of MD evaluated with VCE and make a review of the literature focusing on the endoscopic *** SUMMARYWe present four cases of MD confirmed by surgery. They were all adult males with ages going from 18 to 50 years, referred to our service from 2004 to 2018, due to obscure gastrointestinal bleeding （OgIB）. Theygarcía-Compeán D et al . Merckel’s diverticulum diagnosis by VCEhad a history of 1 mo to 10 years of overt and occult bleeding episodes. Laboratory blood test showed an iron-deficiency anemia from 4 to 9 g/dL of hemoglo-bin that required multiple hospitalizations and blood transfusions in all cases. Repeated upper digestive endoscopies and colonoscopies were negative. Small bowel was examined with VCE, which revealed double lumen images in all cases, one with polyps and three with circumferential ulcers in the diverticulum. however, based on VCE findings, preoperative diagnosis of MD was suggested only in two patients. Capsule was retain-ed in one patient, which was recovered with surgery. The anatomopathological report revealed ulcerated ectopic gastric mucosa in all *** is useful for the diagnosis of MD. however, endo-scopic characteristics must be recognized in order to establish preoperative diagnosis.

关键词： Meckel’s diverticulum Endoscopic features Video capsule endoscopy Wireless capsule endoscopy Review Case report

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Post-acute pancreatitis diabetes:A complication waiting for more recognition and understanding

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World journal of gastroenterology 2023年第28期29卷 4405-4415页

作者： Diego garcía-Compeán Alan R jiménez-Rodríguez juan M Muñoz-Ayala josé A gonzález-gonzález héctor j maldonado-g.rza jesús Z Villarreal-Pérez Department of gastroenterology Autonomous University of Nuevo LeónMonterrey 64700Nuevo LeónMexico Department of Endocrinology Autonomous University of Nuevo LeónMonterrey 64700Nuevo LeónMexico

Post-acute pancreatitis diabetes(PAPD)is the second most common type of diabetes below type 2 diabetes *** to the boom in research on this entity carried out during the last decade,its recognition has ***,much of the medical community still does not recognize it as a medium and long-term complication of acute pancreatitis(AP).Recent prospective cohort studies show that its incidence is about 23%globally and 34.5%in patients with severe *** the overall increase in the incidence of AP this complication will be certainly seen more *** to its high morbidity,mortality and difficult control,early detection and treatment are ***,its risk factors and pathophysiological mechanisms are not clearly *** diagnosis should be made excluding pre-existing diabetes and applying the criteria of the American Diabetes Association after 90 d of resolution of one or more AP *** review will show the evidence published so far on the incidence and prevalence,risk factors,possible pathophysiological mechanisms,clinical outcomes,clinical characteristics and preventive and corrective management of *** important gaps needing to be clarified in forthcoming studies will also be discussed.

关键词： Acute pancreatitis Diabetes mellitus Chronic pancreatitis Post-pancreatitis diabetes Pancreatogenic diabetes

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The ecological scale mediates whether trees experience drought legacies in radial growth

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Forest Ecosystems 2023年第3期10卷 298-306页

作者： héctor hernández-Alonso jaime Madrigal-gonzález Fernando Silla Area of Ecology Faculty of BiologyUniversidad de SalamancaE-37007SalamancaSpain iuFOR-EiFAB Campus de SoriaUniversidad de ValladolidE-42004SoriaSpain

The impact of lag effects produced by disturbances on primary production has been a major concern among ecologists during the last *** and extreme climatic events are imposing drastic reductions in radial growth of trees as evidenced in tree-rings series Dendrochronological samples are obtained at tree level but analyzed at an aggregated scale(i.e.,mean chronologies),although aggregating tree-ring chronology on a regional scale may reduce the possibility of studying the variability of individual tree response to drought,by amplifying the average population ***,we conducted experimental research in which 370 trees of 5 species were analyzed to assess the potential statistical and scaling issues that may occur when using regressionbased methods to analyze ecosystem responses to *** legacy effects were quantified using individual and aggregated ***,lag effects were validated using confidence and prediction intervals to identify values falling outside the certainty of the climate-growth model Individual scale legacy effects contrasted with confidence intervals were commonly distributed across species but were scarce when compared with prediction *** analysis of aggregated scale legacies detected significant growth reductions when validated using prediction intervals;however,individual scale legacy lag effects were not *** finding directly contrasts the results obtained when using an aggregated *** results provide empirical evidence on how aggregating ecological data to infer processes that emerge from an individual scale can lead to distorted *** therefore encourage the use of individual based statistical and ecological procedures to analyze tree rings as a means of further understanding the ecosystem responses to disturbances.

关键词： Legacy effects Drought disturbances Tree growth Tree-ring width Dendrochronology Individual scale Mountainous forests

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Arrhythmogenic mechanisms in ryanodine receptor channelopathies

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Science China(Life Sciences) 2015年第1期58卷 54-58页

作者： ZhAO Yan-Ting VALDIVIA Carmen R. gURROLA georgina B. hERNNDEZ jonathan j. VALDIVIA héctor h. Center for Arrhythmia Research Department of Internal MedicineCardiovascular DivisionUniversity of Michigan

Ryanodine receptors(Ry Rs) are the calcium release channels of sarcoplasmic reticulum(SR) that provide the majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle *** their intracellular environment,Ry R channels are regulated by a variety of cytosolic and luminal factors so that their output signal(Ca2+) induces finely-graded cell contraction without igniting cellular processes that may lead to aberrant electrical activity(ventricular arrhythmias) or cellular *** importance of Ry R dysfunction has been recently highlighted with the demonstration that point mutations in RYR2,the gene encoding for the cardiac isoform of the Ry R(Ry R2),are associated with catecholaminergic polymorphic ventricular tachycardia(CPVT),an arrhythmogenic syndrome characterized by the development of adrenergically-mediated ventricular tachycardia in individuals with an apparently normal *** we summarize the state of the field in regards to the main arrhythmogenic mechanisms triggered by Ry R2 channels harboring mutations linked to *** CPVT mutations characterized to date endow Ry R2 channels with a gain of function,resulting in hyperactive channels that release Ca2+ spontaneously,especially during *** spontaneous Ca2+ release is extruded by the electrogenic Na+/Ca2+ exchanger,which depolarizes the external membrane(delayed afterdepolarization or DAD) and may trigger untimely action ***,a rare set of CPVT mutations yield Ry R2 channels that are intrinsically hypo-active and hypo-responsive to stimuli,and it is unclear whether these channels release Ca2+ spontaneously during *** discuss novel cellular mechanisms that appear more suitable to explain ventricular arrhythmias due to Ry R2 loss-of-function mutations.

关键词： ryanodine receptors CPVT sarcoplasmic reticulum cardiac arrhythmias

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Multi-objective optimization design of bridge piers with hybrid heuristic algorithms

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 420-432页

作者： Francisco j. MARTINEZ-MARTIN Fernando gONZALEZ-VIDOSA Antonio hOSPITALER Víctor YEPES Department of geotechnical Engineering Universitat Politècnica de València 46022 Valencia Spain Department of Construction Engineering ICITECH Universitat Politècnica de València 46022 Valencia Spain

This paper describes one approach to the design of reinforced concrete (RC) bridge piers, using a three-hybrid multi- objective simulated annealing (SA) algorithm with a neighborhood move based on the mutation operator from the genetic algorithms (gAs), namely MOSAMO1, MOSAMO2 and MOSAMO3. The procedure is applied to three objective functions: the economic cost, the reinforcing steel congestion and the embedded CO 2 emissions. Additional results for a random walk and a descent local search multi-objective algorithm are presented. The evaluation of solutions follows the Spanish Code for structural concrete. The methodology was applied to a typical bridge pier of 23.97 m in height. This example involved 110 design variables. Results indicate that algorithm MOSAMO2 outperforms other algorithms regarding the definition of Pareto fronts. Further, the proposed procedure will help structural engineers to enhance their bridge pier designs.

关键词： Bridge piers Concrete structures Multi-objective optimization Simulated annealing (SA) Structural design

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Variable exponent hardy spaces associated with discrete Laplacians on graphs

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Science China Mathematics 2019年第1期62卷 73-124页

作者： Víctor Almeida jorge j.Betancor AlejANDro j.Castro Lourdes Rodríguez-Mesa Departamento de Análisis Matemático Universidad de La Laguna Department of Mathematics Nazarbayev University

In this paper we develop the theory of variable exponent hardy spaces associated with discrete Laplacians on infinite graphs. Our hardy spaces are defined by square integrals, atomic and molecular decompositions. Also we study boundedness properties of Littlewood-Paley functions, Riesz transforms, and spectral multipliers for discrete Laplacians on variable exponent hardy spaces.

关键词： graphs discrete Laplacian hardy spaces variable exponent square functions spectral multipliers

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high-aspect-ratio nanoimprint process chains

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Microsystems & Nanoengineering 2017年第1期3卷 221-232页

作者： Víctor j.Cadarso Nachiappan Chidambaram Loïc jacot-Descombes helmut Schift Laboratory for Micro-and Nanotechnology Research Division Synchrotron Radiation and NanotechnologyPaul Scherrer InstitutVilligen 5232Switzerland Micro Resist Technology gmbh Köpenicker Straße 325Berlin 12555Germany

Different methods capable of developing complex structures and building elements with high-aspect-ratio nanostructures combined with microstructures,which are of interest in nanophotonics,are *** originals for subsequent replication steps,two families of masters were developed:(i)3.2μm deep,180 nm wide trenches were fabricated by silicon cryo-etching and(ii)9.8μm high,350 nm wide ridges were fabricated using 2-photon polymerization direct laser *** emerging technologies enable the vertical smooth sidewalls needed for a successful imprint into thin layers of polymers with aspect ratios exceeding *** with high aspect ratios of up to 28 and no residual layer were produced in Ormocers using the micromoulding into capillaries(MIMIC)process with subsequent *** work presents and balances the different fabrication routes and the subsequent generation of working tools from masters with inverted tones and the combination of hard and soft *** provides these techniques with a proof of concept for their compatibility with high volume manufacturing of complex micro-and nanostructures.

关键词： cryo-etching direct 6 write laser lithography high aspect ratio moulding nanoimprint lithography Ormocer photonic nanofences 2-photon polymerization

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