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Biomaterials for Adhesion in Orthopedic Applications:A Review

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再生工程(英文) 2020年第1期1卷 51-63页

作者： Younis Zaokari alicia Persaud Amr Ibrahim Biomedical Engineering Department College of Engineering and Applied SciencesStony Brook UniversityUnited States

Adhesive biomaterials,historically,have had a wide range of applications in all medical *** the extensive variety of biomaterials with adhesion properties,the field of orthopedics benefits from using adhesives which can provide superior biocompatibility,resorbability,and low *** goal of this review is to serve as a reference of the types of adhesive biomaterials used clinically and their specific applicability in the field of *** applications of adhesive biomaterials in orthopedics are as scaffolds,filler materials to treat bone defects and as carrier materials to deposit other bioactive materials to a ***,we review the history and background of adhesive biomaterials and some of their general applications in *** we focus on the various types of adhesive biomaterials which include fibrin,collagen,polyurethane,epoxy resin,cyanoacrylates,polyesters and polymethylmethacrylate,all of which are excellent candidates for the field of *** discuss their properties,current applications in all fields,and advantages and disadvantages found in some ***,we indicate some future directions for adhesive biomaterials in orthopedics and highlight their advantages over conventional biomaterials in orthopedics.

关键词： Adhesive biomaterials Orthopedic biomaterials Osteoinduction Polymer-based biomaterials Fibrin biomaterials

Cellular automata model for traffic flow with safe driving conditions

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Chinese Physics B 2014年第5期23卷 216-226页

作者： María Elena Lárraga Luis alvarez-Icaza Instituto de Ingeniería Universidad Nacional Autónoma de México04510Coyoacán D.F.México

In this paper, a recently introduced cellular automata （CA） model is used for a statistical analysis of the inner micro-scopic structure of synchronized traffic flow. The analysis focuses on the formation and dissolution of clusters or platoons of vehicles, as the mechanism that causes the presence of this synchronized traffic state with a high flow. This platoon formation is one of the most interesting phenomena observed in traffic flows and plays an important role both in manual and automated highway systems （AHS）. Simulation results, obtained from a single-lane system under periodic boundary conditions indicate that in the density region where the synchronized state is observed, most vehicles travel together in pla- toons with approximately the same speed and small spatial distances. The examination of velocity variations and individual vehicle gaps shows that the flow corresponding to the synchronized state is stable, safe and highly correlated. Moreover, results indicate that the observed platoon formation in real traffic is reproduced in simulations by the relation between vehicle headway and velocity that is embedded in the dynamics definition of the CA model.

关键词： traffic flow models synchronized traffic cellular automata platoons formation

Glial kon/NG2 gene network for central nervous system repair

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Neural Regeneration Research 2017年第1期12卷 31-34页

作者： Maria Losada-Perez Neale Harrison alicia Hidalgo School of Biosciences University of BirminghamBirminghamEnglandUK Universidad Autonoma de Madrid MadridSpain

The glial regenerative response to central nervous system（CNS） injury,although limited,can be harnessed to promote regeneration and *** provokes the proliferation of ensheathing glial cells,which can differentiate to remyelinate axons,and partially restore *** response is evolutionarily conserved,strongly implying an underlying genetic *** mammals,it is elicited by NG2 glia,but most often newly generated cells fail to *** an important goal had been to find out how to promote glial differentiation following the proliferative response.A gene network involving Notch and prospero（pros） controls the balance between glial proliferation and differentiation in flies and mice,and promotes CNS repair at least in fruit-flies.A key missing link had been how to relate the function of NG2 to this gene *** findings by Losada-Perez et al.,published in JCB,demonstrated that the Drosophila NG2 homologue kon-tiki（kon） is functionally linked to Notch and pros in *** engaging in two feedback loops with Notch and Pros,in response to injury,Kon can regulate both glial cell number and glial shape homeostasis,essential for *** offers powerful genetics to unravel the control of stem and progenitor cells for regeneration and repair.

关键词： NG2 kon-tiki glia Drosophila injury regeneration repair CNS

GM3-containing nanoparticles in immunosuppressed hosts:Effect on myeloid-derived suppressor cells

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World Journal of Immunology 2014年第2期4卷 98-106页

作者： Audry Fernández Liliana Oliver Rydell alvarez Luis E Fernández Circe mesa Immunobiology Division Center of Molecular Immunology Innovation Division Center of Molecular Immunology

Cancer vaccines to date have not broadly achieved a significant impact on the overall survival of patients. The negative effect on the immune system of the tu-mor itself and conventional anti-tumor treatments such as chemotherapy is, undoubtedly, a key reason for these disappointing results. Myeloid-derived suppres-sor cells （MDSCs） are considered a central node of the immunosuppressive network associated with tumors. These cells inhibit the effector function of natural killer and CD8＋ T cells, expand regulatory T cells and can differentiate into tumor-associated macrophages within the tumor microenvironment. Thus, overcoming the suppressive effects of MDSCs is likely to be criti-cal for cancer immunotherapy to generate effective anti-tumor immune responses. However, the capacity of cancer vaccines and particularly their adjuvants to overcome this inhibitory population has not been well characterized. Very small size proteoliposomes （VSSP） is a nanoparticulated adjuvant specifcally designed to be formulated with vaccines used in the treatment of immunocompromised patients. This adjuvant contains immunostimulatory bacterial signals together with GM3 ganglioside. VSSP promotes dendritic cell maturation, antigen cross-presentation to CD8＋ T cells, Th1 polar-ization, and enhances CD8＋ T cell response in tumor-free mice. Currently, four cancer vaccines using VSSP as the adjuvant are in Phase？Ⅰ？and Ⅱ clinical trials. In this review, we summarize our work characterizing the unique ability of VSSP to stimulate antigen-specifc CD8＋ T cell responses in two immunocompromised sce-narios; in tumor-bearing mice and during chemother-apy-induced leukopenia. Particular emphasis has been placed on the interaction of these nanoparticles with MDSCs, as well as comparison with other cancer vac-cine adjuvants currently in preclinical or clinical studies.

关键词： Very small size proteoliposomes Adjuvants Tumors Myeloid-derived suppressor cells Leukopenia Chemotherapy

Carbon stocks in a highly fragmented landscape with seasonally dry tropical forest in the Neotropics

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Forest Ecosystems 2022年第2期9卷 168-177页

作者： N.mesa-Sierra J.Laborde R.Chaplin-Kramer F.Escobar Instituto Tecnologico y de Estudios Superiores de Occidente Centro Interdisciplinario para la Formacion y Vinculacion SocialPeriferico Sur Manuel Gomez Morin 858545604TlaquepaqueJaliscoMexico Gnosis-Naturaleza con ciencia A.C.Lorenzo Barcelata 510145239GuadalajaraJaliscoMexico Instituto de Ecologia A.C.Ecologia FuncionalCarretera Antigua a Coatepec 351El Haya91073XalapaVeracruzMexico Natural Capital Project Woods Institute for the EnvironmentStanford University327 Campus DriveStanfordCA94305USA Institute on the Environment University of Minnesota1954 Buford AveSt.PaulMinnesota55108USA Instituto de Ecologia A.C.EcoetologiaCarretera Antigua a Coatepec 351El Haya91073XalapaVeracruzMexico

Background:Global modeling of carbon storage and sequestration often mischaracterizes unique ecosystems such as the seasonally dry tropical forest of the central region of the Gulf of Mexico,because species diversity is usually underestimated,as is their carbon *** this study,aboveground and soil carbon stocks were estimated to determine the climate mitigation potential of this highly degraded landscape(<25%of forest cover).Results:Tree species in the study area had carbon content values that were 30%–40%higher than the standard value proposed by the IPCC(i.e.,50%).Tropical oak forest in the region,despite its restricted distribution and low species richness,accounted for the highest mean carbon stocks per unit *** main factors driving spatial variability in carbon stocks were:maximum precipitation,soil organic matter,clay and silt *** strong relationship was found between aboveground carbon stocks and soil organic carbon in the study ***-fication of carbon stocks is an important consideration in the assessment of the conservation value of remnants of native vegetation in human-modified ***:This study demonstrates the importance of the highly fragmented tropical dry regions of the Neo-tropics in maintaining landscape functionality and providing key ecosystem services such as carbon *** results also highlight how crucial field-based studies are for strengthening the accuracy of global ***,this approach reveals the real contribution of ecosystems that are not commonly taken into account in the mitigation of climate change effects.

关键词： Seasonally dry tropical region Ecosystem services Carbon sequestration Human modified landscapes Climate change mitigation

Tales of the Tail and Sperm Head Aches --Changing concepts on the prognostic significance of sperm pathologies affecting the head, neck and tail

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Asian Journal of Andrology 2012年第1期14卷 14-23,174页

作者： Hector E Chemes Cristian alvarez Sedo Laboratory of Testicular Physiology and Pathology Center for Research in Endocrinology National Research Council （CONICET） Endocrinology Division Buenos Aires Children＇s Hospital Gallo 1330 C1425SEFD Buenos Aires Argentina Centro de Estudios en Ginecologia y Reproduccion （CEGyR） C1425SEFD Buenos Aires Argentina

This article presents an update on the variable prognostic significance of different sperm pathologies in patients with severe male factor infertility due to morphology and motility disorders. Severe asthenozoospermia is one of the leading causes of male infertility as spermatozoa cannot reach the oocyte and/or penetrate normally. Identifying structural causes of sperm immotility was of great concern before the advent of intracytoplasmic sperm injection （ICSI）, because immotility was the limiting factor in the treatment of these patients. In these cases, in vitro methods are used to identify live spermatozoa or stimulate sperm motility to avoid selection of non-viable cells. With these advances, fertilization and pregnancy results have improved dramatically. The identification of genetic phenotypes in asthenozoospermia is important to adequately inform patients of treatment outcomes and risks. The one sperm characteristic that seriously affects fertility prognosis is teratozoospermia, primarily sperm head and neck anomalies. Defects of chromatin condensation and acrosomal hypoplasia are the two most common abnormalities in severe teratozoospermia. The introduction of microscopic methods to select spermatozoa and the development of new ones to evaluate sperm quality before ICSI will assure that ultrastructural identification ofsperm pathologies will not only be of academic interest, but will also be an essential tool to inform treatment choice. Herein, we review the differential roles played by sperm components in normal fertilization and early embryo development and explore how assisted reproductive technologies have modified our concepts on the prognostic significance of sperm pathologies affecting the head, neck, mid-piece and tail.

关键词： acrosomal hypoplasia chromatin anomalies fertility prognosis intracytoplasmic sperm injection intracytoplasmic injection of morphologically selected spermatozoa sperm neck defects sperm pathologies tail abnormalities teratozoospermia

Limited proteomic response in the marine snail Melarhaphe neritoides after long-term emersion

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Current Zoology 2017年第5期63卷 487-493页

作者： Angel R DIZ Margarita alvarez-RODRiGUEZ Monica R. ROMERO Emilio FOLAN-alvarez Juan GALINDO Department of Biochemistry Genetics and Immunology Faculty of Biology University of Vigo Vigo 36310 Spain Toralla Marine Science Station (ECIMAT) Universidad de Vigo Vigo 36331 Spain Institute of Marine Research (IIM) CSIC Vigo 36208 Spain

Rocky intertidal organisms are commonly exposed to environmental gradients, promoting adapta-tions to these conditions. Emersion time varies along the intertidal range and in the supralittoralzone is frequently larger than a single tidal cycle, even lasting for weeks. The planktonic-dispersinggastropod Melarhaphe neritoides is a common species of the high shore, adapted to reduce waterloss in order to survive during long-term emersion. In this study, we investigated the molecular re-sponse, at the proteome level, of M. neritoides collected in high-shore tide pools to a series ofemersion periods, from 8 to 24 days, in laboratory conditions. We compared this response to indi-viduals maintained submerged during this period, because this was their original habitat. We alsoincluded a reversion treatment in the study, in which emersed individuals were returned to the sub-merged conditions. Although we detected an increase in overall protein concentration with longeremersion periods, contrary to general expectation, the two dimensional electrophoresis （2DE）-based proteomic analysis did not show significant differences between the treatments at the levelof individual protein spots, even after an emersion period of 24 days. Our results suggest that themetabolism remains unaltered independent of the treatment carried out or the changes are verysubtle and therefore difficult to detect with our experimental design. We conclude that M. neri-toides could be equally adapted to emersion and submersion without drastic physiologicalchanges.

关键词： daptation, 2DE proteomics, environmental gradient, intertidal zone, metabolic rate depression.

In vivo optical quality of posterior-chamber phakic implantable collamer lenses with a central port

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Eye and Vision 2021年第5期8卷 295-302页

作者： Robert Montés-Micó Francisco Pastor-Pascual Enrique Artiaga-Elordi Ramón Ruiz-mesa Pedro Tañá-Rivero Optics and Optometry&Vision Sciences Department University of Valenciac/o Dr Moliner 5046100 ValenciaSpain Oftalvist Clinic ValenciaSpain

Background:The aim of this review is to summarize the optical quality results in patients following the implantation of the V4c implantable collamer lens with a central port(ICL,STAAR Surgical Inc.).Main text:A literature search in several databases was carried out to identify those publications,both prospective,retrospective and/or comparative with other refractive surgery procedures,reporting optical outcomes of patients who were implanted with the V4c ICL model.A total of 17 clinical studies published between 2012 and 2021 were included in this review.A detailed analysis of the available data was performed including number of eyes,follow-up and preoperative spherical ***,the review focused on several optical parameters including higher-order aberrations(HOAs),modulation transfer function(MTF)cut-off frequency and Strehl *** review encompassed a total of 817 eyes measured using different optical devices based on Hartmann-Shack,retinal image quality measurement and ray-tracing technologies at different ***:The outcomes found in this review lead us to conclude that the ICL V4c model provides good optical quality,by means of different metrics,when implanted.

关键词： Implantable collamer lens Phakic Optical quality Higher order aberrations Modulation transfer function

CD47:a new player in phagocytosis and xenograft rejection

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Cellular & Molecular Immunology 2011年第4期8卷 285-288页

作者： Nalu Navarro-alvarez Yong-Guang Yang Columbia Center for Translational Immunology Columbia University Medical CenterNew YorkNYUSA

Organ transplantation is limited by the availability of human donor *** transplantation of organs and tissues from other species(xenotransplantation)would supply an unlimited number of organs and offer many other advantages for which the pig has been identified as the most suitable ***,the robust immune responses to xenografts remain a major obstacle to clinical application of *** more vigorous xenograft rejection relative to allograft rejection is largely accounted for by the extensive genetic disparities between the donor and *** activate host immunity not only by expressing immunogenic xenoantigens that provide the targets for immune recognition and rejection,but also by lacking ligands for the host immune inhibitory *** review is focused on recent findings regarding the role of CD47,a ligand of an immune inhibitory receptor,signal regulatory protein alpha(SIRPa),in phagocytosis and xenograft rejection.

关键词： CD47 macrophage signal-regulatory protein alpha xenotransplantation