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Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

Neural Regeneration Research 2023年第12期18卷 2573-2581页

作者： Sílvia Sousa Chambel Célia Duarte Cruz Experimental Biology Unit Department of BiomedicineFaculty of Medicine of PortoUniversity of PortoPortoPortugal Translational NeuroUrology Instituto de Investigação e Inovação em Saúde-i3S and IBMCUniversidade do PortoPortoPortugal

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory prot

关键词： chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19

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Influence of location of large-scale asperity on shear strength of concrete-rock interface under eccentric load

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 449-460页

作者： Dipen Bista Gabriel Sas Fredrik Johansson Leif lia SINTEF Narvik As Narvik8517Norway Norwegian University of Science and Technology(NTNU) Trondheim7491Norway Royal Institute of Technology(KTH) Stockholm10044Sweden

The location and geometry of large-scale asperity present at the foundation of concrete gravity dams and buttress dams affect the shear resistance of the concrete-rock ***,the parameters describing the frictional resistance of the interface usually do not account for these *** could result in an underestimate of the peak shear stre ngth,which leads to significantly conservative design for new dams or unnecessary stability enhancing measures for existing *** aim of this work was to investigate the effect of the location of first-order asperity on the peak shear strength of a concrete-rock interface under eccentric load and the model discrepancy associated with the commonly used rigid body methods for calculating the factor of safety(FS)against *** this,a series of direct and eccentric shear tests under constant normal load(CNL)was carried out on concrete-rock *** peak shear strengths measured in the tests were compared in terms of asperity location and with the predicted values from analytical rigid body *** results showed that the large-scale asperity under eccentric load significantly affected the peak shear ***,unlike the conventional assumption of sliding or shear failure of an asperity in direct shear,under the effect of eccentric shear load,a tensile failure in the rock or in the concrete could occur,resulting in a lower shear strength compared with that of direct shear *** results could have important implications for assessment of the FS against sliding failure in the concrete-rock interface.

关键词： Shear strength Concrete-rock interface Asperity location Eccentric load Model discrepancy Dam foundation

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Numerical Solution for a Non-Fickian Diffusion in a Periodic Potential

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Communications in Computational Physics 2013年第2期13卷 502-525页

作者： Adérito Araújo Amal K.Das Cidália Neves Ercília Sousa CMUC Department of MathematicsUniversity of Coimbra3001-454 CoimbraPortugal Department of Physics DalhousieUniversityHalifaxNova Scotia B3H3J5Canada ISCAC Polytechnic Institute of Coimbra3040-316 CoimbraPortugal

Numerical solutions of a non-Fickian diffusion equation belonging to a hyperbolic type are presented in one space *** Brownian particle modelled by this diffusion equation is subjected to a symmetric periodic potential whose spatial shape can be varied by a single *** consider a numerical method which consists of applying Laplace transform in time;we then obtain an elliptic diffusion equation which is discretized using a finite difference *** analyze some aspects of the convergence of the *** results for particle density,flux and mean-square-displacement(covering both inertial and diffusive regimes)are presented.

关键词： Numerical methods Laplace transform telegraph equation periodic potential non-Fickian diffusion

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Hard carbon derived from coconut shells,walnut shells,and corn silk biomass waste exhibiting high capacity for Na-ion batteries

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Journal of Energy Chemistry 2021年第7期30卷 207-218页

作者： Cristina Nita Biao Zhang Joseph Dentzer Camélia Matei Ghimbeu Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Center for Advanced Laser Technologies(CETAL) National Institute for LasersPlasma and Radiation PhysicsAtomistilor 409 bisRO-77125 MagureleRomania Department of Applied Physics The Hong Kong Polytechnic UniversityKowloonHong KongChina Réseau sur le Stockage Electrochimique de l’Energie(RS2E) CNRS FR345933 Rue Saint Leu80039 Amiens CedexFrance

In recent years,hard carbon materials have gained significant interest as anode materials for Na-ion *** waste is considered one of the most interesting,renewable,available,and cost-effective precursor to obtain hard carbon(HC);however,HC properties must be finely tuned to achieve performance comparable to those provided by Li-ion *** this work,three biomass wastes(coconut shells,walnut shells,and corn silk) were evaluated as potential precursors for HC preparation involving a pyrolysis process and subsequent acid washing to remove the inorganic *** obtained materials exhibited low and similar specific surface areas(<10 m^(2)·g^(-1)), but they presented different structures and surface *** walnut shell HC possessed a lower amount of inorganic impurities and oxygen-based functional groups compared to the coconut shell and corn silk HCs,leading to higher initial coulombic efficiency(iCE).The structural organization was higher in the case of the walnut shell HC,while the corn silk HC revealed a heterogeneous structure combining both highly disordered carbon and localized graphitized *** HCs delivered high initial reversible capacities between 293 and 315 mAh g^(-1) at 50 mA g^(-1) current rate,which remained rather stable during long-term *** best capacity(293 mAh g^(-1) after 100 charge/discharge cycles) and highest capacity retention(93%) was achieved in walnut HCs in half-cells,which could be associated with its higher sp2 C content,better organized structure,and fewer *** "adsorption-insertion" Na storage mechanism is suggested based on several *** walnut HCs exhibited an attractive energy density of 279 Wh/kg when tested in full cells.

关键词： Biomass Pyrolysis Hard carbon Anode Na-ion batteries Energy storage

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Characterization and Modification of a Clay Mineral Used in Adsorption Tests

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Journal of Minerals and Materials Characterization and Engineering 2015年第4期3卷 277-288页

作者： natália Costa Dias Patrícia Arns Steiner Maria Cristina Borba Braga Water Resources and Environmental Engineering Post-Graduate Program Department of Hydraulics and Sani-tation Parana Federal University Curitiba Brazil

Clay minerals are widespread in natural systems and have been widely used for the removal of pollutants. In this study, natural expanded vermiculite was used in adsorption tests to remove ammonium nitrogen from landfill leachate. The modification of vermiculite was carried out using NaOH and HCl, and for both modifications the best concentration was 0.1 mol/L. The results produced by XRD (X-ray diffraction) showed that Al replaced K after modification of the vermiculite using HCl and that Mg and Na replaced K after modification using NaOH. It was observed that the adsorption capacity increased as the percentage in mass of K diminished. The Langmuir is the isotherm that presents the best fit of the data, and the values of RL (the Langmuir coefficient) suggest that the adsorption is linear. The thermodynamic parameters indicate that the process is spontaneous and endothermic, that there is a high affinity between the adsorbate and the adsorbent, and that physical adsorption is prevalent.

关键词： Adsorption Isotherms Adsorption Thermodynamics Clay Minerals Expanded Vermiculite Landfill Leachate Vermiculite

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Effect of Concentration and Residence Time of Joncryl■ADR4368 on Melt Processability of Poly(3-hydroxybutyrate)

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Journal of Renewable Materials 2024年第12期12卷 2079-2094页

作者： Jéssica da Silva Chagas JoséElson Soares Filho natália Fernanda Inocêncio Silva Marcelo Massayoshi Ueki Eliton Souto de Medeiros Renate Maria Ramos Wellen Mauricio Pinheiro de Oliveira Gelsoneide da Silva Gois Yêda Medeiros Bastos de Almeida Amélia S.F.Santos Post-Graduation Program in Materials Engineering(PPCEM) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Laboratory of Materials and Biosystems(LAMAB) Federal University of Paraíba(UFPB)João PessoaPB 58051-900Brazil Department of Materials Engineering Federal University of Sergipe(UFS)Jardim Rosa ElzeSão CristóvãoSE 49100-000Brazil Institute of Science and Technology Federal University of São Paulo(UNIFESP)São Josédos CamposSP 12231-280Brazil Department of Chemical Engineering Federal University of Pernambuco(UFPE)Cidade UniversitáriaRecifePE 50670-901Brazil

Poly(3-hydroxybutyrate)(PHB)is a biothechnological and biodegradable thermoplastic polymer from the polyhydroxyalkanoates(PHAs)family,whose chain regularity,high molecular weight,and physical and mechanical properties comparable to polypropylene(PP)are characteristics that have made PHB a prominent commercial ***,its susceptibility to thermal degradation and hydrolysis has limited many *** address the challenges associated with processing,a random copolymer of 95.86 mol%3-hydroxybutyrate and 4.14 mol%3-hydroxyvalerate(referred as PHB)was compounded without(neat PHB)and with 0.25,0.5,1,and 1.5 wt%of chain extender(Joncryl■ADR 4368),consisting of multifunctional epoxy groups,and melt mixed in an internal mixer at 170℃,50 rpm,and residence times of 5,10,and 15 *** effect of chain extender concentration and residence time on the effectiveness of Joncryl■ADR 4368 to recover the pristine PHB properties were investigated through torque rheometry,melt flow index(MFI),differential scanning calorimetry(DSC),tensile testing,and thermogravimetric *** results indicated that an increase in residence time strongly influenced the prevalence of thermomechanical degradation reactions over chain extension reactions of PHB during processing in the molten *** residence times favored chain extension,while longer times favored chain *** trend led to no enhancement of PHB mechanical properties processed for 10 and 15 min,regardless of additive content *** flow index,thermogravimetric analysis and tensile strength exhibited an asymptotic behavior with the increase in additive concentration,exhibiting a noteworthy improvement in tensile strength and temperature at the highest rate of thermal degradation(TMAX),and a decrease in melt flow index of neat PHB with only 0.25 wt%of additive mixed for 5 *** results found in this work allow additional data for processing PHB by manipulating the ratios of multifunctional chain

关键词： PHB chain extender degradation epoxy groups viscosity

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Nanoparticles as delivery vehicles for antiviral therapeutic drugs

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Engineered Regeneration 2021年第1期2卷 31-46页

作者： Alexander Maus lia Strait Donghui Zhu Department of Biomedical Engineering Stony Brook UniversityUnited States

With the ongoing COVID-19 pandemic still escalating,many researchers are turning to nanotechnology as a method of treatment not only for this pandemic,but in preparation for the pandemics of the *** both a wide variety of biomaterials at their disposal and the recent rise of nanotechnology,scientists now have the means to release and distribute therapeutic drugs in a variety of *** a variety permits medical professionals the ability to choose biomaterials and methods that would provide the best release and treatment methodologies for the viral ailment they are attempting to *** integrative review discusses context of previous pandemics,viral pathogenesis,issues associated with the current state of antiviral delivery systems,numerous biomaterials used for this purpose,and further information regarding the ongoing global COVID-19 pandemic.

关键词： Nanotechnology COVID-19 Antiviral Drug selivery

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Antioxidant Potential of Extracts from Processing Residues from Brazilian Food Industries

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Food and Nutrition Sciences 2013年第8期4卷 211-218页

作者： natália Mezzomo Daniela A. Oliveira Sandra R. S. Ferreira EQA-CTC/UFSC Chemical and Food Engineering Department Federal University of Santa Catarina Florianópolis Brazil

The objective of this work was to estimate the antioxidant potential of the extracts from pink shrimp residue and red grape pomaces (Merlot and Syrah varietals), evaluated according to its antioxidant activity with different analytical methods, associating these properties with the chemical composition of the extract and, as a consequence, with the extraction procedure. The shrimp residue was pre-treated combining cooking, drying, and milling, whereas the grape pomaces were dried and ground. The shrimp residue extracts were obtained by Soxhlet (SOX) and by maceration using hexane (Hx), hexane: isopropanol (50:50) (Hx:IPA), isopropanol, ethanol (EtOH) and acetone as solvents;by ultrasonic maceration (UME) with EtOH;by cold and hot oil extraction with soy and sunflower oils;and by Supercritical Fluid Extraction (SFE) with pure CO2 (100 -?300 bar;313.15 -?333.15 K) and with co-solvent (Hx: IPA and sunflower oil at 2%). The grape pomaces extracts were obtained by SOX using EtOH, ethyl acetate (EtOAc) and Hx;UME with water (H2O), EtOH, EtOAc and Hx;and by SFE performed with pure CO2 (150 -?300 bar;323.15 -?333.15 K) and with cosolvent (EtOH at 15%). The antioxidant activity was determined by the DPPH free radical scavenging procedure and by the β-carotene bleaching method. Higher antioxidant activities in shrimp residue extracts were observed by the β-carotene bleaching method in alcoholic and cetonic extracts, among the low pressure extraction methods, while for the SFE, the higher activities were achieved by the extracts obtained at elevated pressures. For the grape pomaces extracts, the best results were obtained by the DPPH method from the low pressure extractions proceeded with EtOH. The SFE with Merlot pomace at 323.15 K/150 bar (the lowest temperature and pressures tested) presented the best antioxidant activity by the β-carotene bleaching.

关键词： Supercritical Fluid Extraction Shrimp Residue Grape Pomace

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Assessment of resting energy expenditure in patients with cirrhosis

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World Journal of Hepatology 2022年第4期14卷 802-811页

作者： Shaiane Ferreira Cláudio Augusto Marroni Jessica Taina Stein Roberta Rayn Ana Cristhina Henz natália P Schmidt Randhall B Carteri Sabrina Alves Fernandes Postgraduate Program in Hepatology Federal University of Health Sciences of Porto Alegre(UFCSPA)Porto Alegre 90050-170Brazil Department of Nutrition Centro Universitário Metodista-IPAPorto Alegre 90420-060Brazil Department of Health and Behavior Catholic University of PelotasPelotas 96015-560Brazil

BACKGROUND Malnutrition affects 20%to 50%of patients with *** may be associated with serious complications and has a direct impact on *** energy expenditure(REE)is an important parameter to guide the optimization of therapy and recovery of nutritional status in patients with ***,the REE of patients with cirrhosis is still unclear,casting doubt upon the optimal nutritional management *** To identify the best method that predicts the REE of cirrhotic patients,using indirect calorimetry(IC)as the gold *** An observational study was performed on 90 patients with *** was assessed by IC,bioelectrical impedance analysis(BIA),and predictive formulas,which were compared using Bland-Altman plots and the Student’s *** REE values measured by IC(1607.72±257.4 kcal)differed significantly from those determined by all other methods(BIA:1790.48±352.1 kcal;Harris&Benedict equation:2373.54±254.9 kcal;IOM equation:1648.95±185.6 kcal;Cunningham equation:1764.29±246.2 kcal),except the Food and Agriculture Organization of the United nations,World Health Organization,and United nations University(FAO/WHO/UNU)(1616.07±214.6 kcal)and McArdle(1611.30±241.8 kcal)*** found no significant association when comparing IC and 24-h dietary recall among different Child-Pugh classes of *** The IOM and FAO/WHO/UNU equations have the best agreement with the *** results indicate a possibility of different tools for the clinical practice on cirrhotic patients.

关键词： Liver cirrhosis Calorimetry Indirect Energy metabolism Malnutrition

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Building segmentation and outline extraction from UAV image-derived point clouds by a line growing algorithm

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International Journal of Digital Earth 2017年第11期10卷 1077-1097页

作者： Yucheng Dai Jianhua Gong Yi lia Quanlong Feng State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Beijing Piesat Information Technology Co. Ltd.BeijingPeople’s Republic of China

This paper presents an approach to process raw unmanned aircraft vehicle(UAV)image-derived point clouds for automatically detecting,segmenting and regularizing buildings of complex urban *** regularizing,we mean the extraction of the building footprints with precise position and *** the first step,vegetation points were extracted using a support vector machine(SVM)classifier based on vegetation indexes calculated from color information,then the traditional hierarchical stripping classification method was applied to classify and segment individual *** the second step,we first determined the building boundary points with a modified convex hull ***,we further segmented these points such that each point was assigned to a fitting line using a line growing ***,two mutually perpendicular directions of each individual building were determined through a W-k-means clustering algorithm which used the slop information and principal direction ***,the building edges were regularized to form the final building *** and quantitative measures were used to evaluate the performance of the proposed approach by comparing the digitized results from ortho images.

关键词： Line growing algorithm regularization UAV image-derived point cloud vegetation index W-k-means clustering algorithm

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