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Impact of source tissue and ex vivo expansion on the characterization of goat mesenchymal stem cells

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Journal of Animal Science and Biotechnology 2015年第2期6卷 230-251页

作者： Nuradilla Mohamad-Fauzi Pablo J Ross Elizabeth A Maga james d Murray department of Animal Science University of California Institute of Ocean and Earth Sciences University of Malaya department of Population Health and Reproduction University of California

Background： There is considerable interest in using goats as models for genetically engineering dairy animals and also for using stem cells as therapeutics for bone and cartilage repair. Mesenchymal stem cells （MSCs） have been isolated and characterized from various species, but are poorly characterized in goats. Results： Goat MSCs isolated from bone marrow （BM-MSCs） and adipose tissue （ASCs） have the ability to undergo osteogenic, adipogenic and chondrogenic differentiation. Cytochemical staining and gene expression analysis show that ASCs have a greater capacity for adipogenic differentiation compared to BM-MSCs and fibroblasts. different methods of inducing adipogenesis also affect the extent and profile of adipogenic differentiation in MSCs. Goat fibroblasts were not capable of osteogenesis, hence distinguishing them from the MSCs. Goat MSCs and fibroblasts express Cd90, Cd105, Cd73 but not Cd45, and exhibit cytoplasmic localization of OCT4 protein. Goat MSCs can be stably transfected by Nucleofection, but, as evidenced by colony-forming efficiency （CFE）, yield significantly different levels of progenitor cells that are robust enough to proliferate into colonies of integrants following G418 selection. BM-MSCs expanded over increasing passages in vitro maintained karyotypic stability up to 20 passages in culture, exhibited an increase in adipogenic differentiation and CFE, but showed altered morphology and amenability to genetic modification by selection. Conclusions： Our findings provide characterization information on goat MSCs, and show that there can be significant differences between MSCs isolated from different tissues and from within the same tissue. Fibroblasts do not exhibit trilineage differentiation potential at the same capacity as MSCs, making it a more reliable method for distinguishing MSCs from fibroblasts, compared to cell surface marker expression.

关键词： Adipose Bone marrow Characterization differentiation Goat Mesenchymal stem cells

Large-diameter trees and deadwood correspond with belowground ectomycorrhizal fungal richness

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Ecological Processes 2023年第1期12卷 31-45页

作者： Joseph d.Birch james A.Lutz Soren Struckman Jessica R.Miesel Justine Karst department of Plant Soil and Microbial SciencesMichigan State University1066 Bogue StreetEast LansingMI 48824USA department of Wildland Resources and the Ecology Center Utah State University5230 Old Main HillLoganUT 84322-5230USA department of Renewable Resources University of Alberta751 General Services BuildingEdmontonAB T6G 2H1Canada

Background: Large-diameter trees have an outsized influence on aboveground forest dynamics, composition, and structure. Although their influence on aboveground processes is well studied, their role in shaping belowground fungal communities is largely unknown. We sought to test if (i) fungal community spatial structure matched aboveground forest structure;(ii) fungal functional guilds exhibited differential associations to aboveground trees, snags, and deadwood;and (iii) that large-diameter trees and snags have a larger influence on fungal community richness than smaller-diameter trees. We used MiSeq sequencing of fungal communities collected from soils in a spatially intensive survey in a portion of Cedar Breaks National Monument, Utah, USA. We used random forest models to explore the spatial structure of fungal communities as they relate to explicitly mapped trees and deadwood distributed across 1.15 ha of a 15.32-ha mapped subalpine forest. Results: We found 6,177 fungal amplicon sequence variants across 117 sequenced samples. Tree diameter, dead-wood presence, and tree species identity explained more than twice as much variation (38.7% vs. 10.4%) for ectomy-corrhizal composition and diversity than for the total or saprotrophic fungal communities. Species identity and dis-tance to the nearest large-diameter tree (≥ 40.2 cm) were better predictors of fungal richness than were the identity and distance to the nearest tree. Soil nutrients, topography, and tree species differentially influenced the composition and diversity of each fungal guild. Locally rare tree species had an outsized influence on fungal community richness. Conclusions: These results highlight that fungal guilds are differentially associated with the location, size, and species of aboveground trees. Large-diameter trees are implicated as drivers of belowground fungal diversity, particularly for ectomycorrhizal fungi.

关键词： Belowground ecology Ectomycorrhizal fungi Pinus flexilis Pinus longaeva Saprotrophic fungi Smithsonian ForestGEO Spatial dynamics Utah Forest dynamics Plot

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A comprehensive review of select smart polymeric and gel actuators for soft mechatronics and robotics applications:fundamentals,freeform fabrication,and motion control

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International Journal of Smart and Nano Materials 2017年第4期8卷 144-213页

作者： james d.Carrico Tom Tyler Kam K.Leang design AutomationRoboticsand Control(DARC)LaboratoryDepartment of Mechanical EngineeringUniversity of UtahSalt Lake CityUTUSA

Smart polymeric and gel actuators change shape or size in response to stimuli like electricity,heat,or *** smart polymeric-and gel-based actuators are compliant and well suited for development of soft mechatronic and robotic *** paper provides a thorough review of select smart polymeric and gel actuator materials where an automated and freeform fabrication process,like 3d printing,is exploited to create custom shaped monolithic *** particular,the advantages and limitations,examples of applications,manufacturing and fabrication techniques,and methods for actuator control are ***,a rigorous comparison and analysis of some of the advantages and limitations,as well as manufacturing processes,for these materials,are presented.

关键词： Smart polymeric actuators gel actuators soft mechatronics

Multiscale analysis of composite material reinforced by randomly-dispersed particles

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International Journal of Smart and Nano Materials 2012年第1期3卷 2-13页

作者： Jiaoyan Li james d.Lee Ken P.Chong The George Washington University WashingtonDC 20052USA National Institute of Standards and Technology GaithersburgMD 20899USA

A multiscale analysis method is presented in which detailed information on the microscopic level is incorporated into macroscopic models capable of simulating damage evolution and ultimate *** composite considered is reinforced by randomly-dispersed particles,which reflects the statistical characteristics of real materials,such as cement-based ***,a three-dimensional material body is decomposed into many unit *** unit cell is reinforced by a cylindrical particle,the orientation of which is characterized by three Euler angles generated by the random number *** on a detailed finite element analysis,the material properties of the representative volume element are *** verification,the properties of the cylindrical particles are set equal to those of the matrix and the computed‘composite’properties reduce exactly to those of the‘isotropic’material,as *** coordinate transformation,the effective material properties of each unit cell are *** assembly of stiffness matrices of all unit cells leads to the stiffness matrix of the whole *** the simple tension loading condition,the initial damaged unit cell can be identified according to the vonMises yield *** stiffness of the damaged unit cell will then be reduced to zero and it will cause stress redistribution and trigger further *** was found that the reinforcement is effective to mitigate and arrest the damage propagation,and therefore prolongs the material’s *** results suggest that the hierarchical coupling approaches used here may be useful for material design and failure protection in composites.

关键词： multiscale analysis random response finite element method representative volume element Euler angle damage propagation

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl LászlóGál Sylvia Nürnberger Barbara Schaedl james Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller david Hercher department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of dentistry Medical University of ViennaViennaAustria department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Using a modern analogue to interpret depositional position in ancient fluvial-tidal channels:Example from the McMurray Formation,Canada

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Geoscience Frontiers 2019年第6期10卷 2219-2238页

作者： Andrew d.La Croix Shahin E.dashtgard james A.MacEachern Energy Initiative University of QueenslandBrisbaneQueensland4072Australia Applied Research in Ichnology and Sedimentology(ARISE)Group Department of Earth SciencesSimon Fraser University8888 University DriveBurnabyBCV5A 1S6Canada

The fluvial-tidal transition(FTT)is a complex depositional zone,where fluvial flow is modified by tides as rivers approach a receiving marine *** in the relative importance of tidal versus fluvial processes lead to a distinctive distribution of sediments that accumulate on channel *** FTT generally consists of three broad zones:(1)a freshwater-tidal zone;(2)a tidally influenced freshwater to brackish-water transition:and(3)a zone of relatively sustained brackish-water conditions with stronger tides.A very common type of deposit through the fluvial-tidal transition,especially on the margins of migrating channels,is inclined heterolithic stratification(IHS).At present,a detailed account of changes in the character of IHS across the FIT of a paleo-channel system has not been reported,although a number of modern examples have been *** fill this gap,we quantitatively assess the sedimentology and ichnology of IHS from seven cored intervals in three geographic areas situated within the youngest paleovalley("A"Valley)in the Lower Cretaceous McMurray Formation of *** compare the data to trends defined along the FTT in the present-day Fraser River in British *** to interpret paleo-depositional position in the ancient fluvial-tidal *** determined that the mean mudstone thickness is 8.2 cm in the southern study area(SA).Mean thickness increases to 11 cm in the central study area(CA),and decreases again to 4.4 cm in the northern study area(NA).The proportion of mudstone is 31%in SA,44%in CA,and 27%in *** mean bioturbation intensity in sands varied from 0.29 in SA and *** 0.28 in *** the other hand,thickness-weighted mean bioturbation intensity(Bl)in mudstone increases from 1.46 in *** 1.77 in *** is 1.94 in *** ichnological diversity also increased from south to *** results show sinilar trends to those of the Fraser River,enabling the identification of a freshwater

关键词： Fluvial-tidal transition McMurray Formation Fraser river Inclined heterolithic stratification Modern analogue Quantirative sedimentology and ichnology

Multiple origin of the lichenicolous life habit in Helotiales,based on nuclear ribosomal sequences

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Fungal diversity 2015年第1期70卷 55-72页

作者： Ave Suija damien Ertz james d.Lawrey Paul diederich Institute of Ecology and Earth Sciences University of Tartu40 Lai st.EE-51005 TartuEstonia département Bryophytes et Thallophytes Jardin botanique national de BelgiqueDomaine de BouchoutB-1860 MeiseBelgium department of Environmental Science and Policy George Mason UniversityMSN 5G810900 University BoulevardManassasVA 20110-2203USA Musée national d’historie naturelle 25 rue MunsterL-2160 LuxembourgLuxembourg

The Helotiales are an ecologically and morphologically highly diverse group of ascomycetes that also includes lichen-inhabiting(lichenicolous)*** generated sequence data of three rdNA regions(nuSSU,nuLSU,5.8S of ITS)from 28 lichenicolous specimens representing nine genera in order to determine their phylogenetic *** on the most complete dataset of helotialean fungi to date,the analyses were performed using Maximum Likelihood(ML)and Bayesian *** results suggest that 1)the lichen-inhabiting life-style in Helotiales was subjected to gains or losses at least three times;2)Thamnogalla,previously tentatively included in Ostropales,is shown to belong to Helotiales;3)ascomata found intermixed with pycnidia of the asexual diplolaeviopsis ranula and possessing the same pigments are tentatively considered as the sexual morph of this taxon,and are shown to belong to Helotiales;4)the lichenicolous species of ***,Llimoniella,Rhymbocarpus,Skyttea,Thamnogalla and Unguiculariopsis form a well-supported clade together with non-lichenicolous encoelioid fungi from the genera Ionomidotis,Cordierites and Encoelia;5)Geltingia associata forms a highly supported clade with the fungicolous asexual fungus Eleutheromyces subulatus,whereas Pezizella epithallina clusters with an aquatic asexual fungus Tetracladium sp.;6)Phaeopyxis punctum belongs to Ostropomycetidae(Lecanoromycetes),but its deep relationships to other groups remain unresolved based on rdNA sequences.

关键词： Convergence Helotiales rdNA Taxonomy diplolaeviopsis Geltingia Llimoniella Pezizella Phaeopyxis Rhymbocarpus Skyttea Thamnogalla Unguiculariopsis

Land use legacy for a tropical myco-heterotroph: how spatial patterns of abundance, reproductive effort and success vary

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Journal of Plant Ecology 2019年第2期12卷 367-375页

作者： Stephen McAuliffe james d.Ackerman Raymond L.Tremblay department of Environmental Science Humboldt State UniversityArcataCAUSA Center for Applied Tropical Ecology and Conservation University of Puerto RicoSan JuanPRUSA department of Biology University of Puerto Rico17 Ave Universidad Suite 1701San JuanPR 00925-2537USA department of Biology University of Puerto RicoHumacaoPRUSA

Aims Human land use such as agriculture and logging can have cascad-ing effects on the environment and severely influence forest eco-systems by altering structure,species composition and community *** activities may have long-term consequences,which impact forest *** investigated the legacy of his-torical anthropogenic land use on the current reproductive effort(RE)and success of the understory,myco-heterotrophic orchid,Wullschlaegelia calcarata in Puerto Rico’s tropical rain forest after 80 years of forest *** Our study site was the 16-ha Luquillo Forest dynamics Plot in the Luquillo Experimental *** used six 10 m×500 m transect lines that spanned areas with differing levels of historic canopy coverage which are correlated with land use *** recorded the abundance of *** plants and measured shoot height,number of flowers,fruit set for all plants and seed set from the most mature,undehisced fruit on a random subset of plants *** sought to determine whether or not there is a legacy of land use history on the RE and success of *** the varying degrees of historic disturbance,we predicted that RE and success would be highest in minimally disturbed old-growth forest,and that soil type differences would be insufficient to affect RE or *** Findings We found 1607 plants of ***,and only one was detected in the most historically disturbed area of the *** orchids were most abundant in the two least historically disturbed ***,the prevailing trend in all measures of RE is in the opposite direction with greater RE in the forest plots with intermediate levels of histori-cal ***,the best model(as a function of AICc and weights)to predict RE is a combination of soil type and cover ***,our measures of reproductive success(fruit and seed set)were best in the least historically disturbed sites and were not associated with soil ***,the b

关键词： forest recovery Orchidaceae tropical forest disturbance ecology Wullschlaegelia

Human recombinant soluble ACE2(hrsACE2)shows promise for treating severe COVId19

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Signal Transduction and Targeted Therapy 2020年第1期5卷 303-304页

作者： Tarek Mohamed Abd El-Aziz Ahmed Al-Sabi james d.Stockand department of Cellular and Integrative Physiology University of Texas Health Science Center at San AntonioSan AntonioTX 78229-3900USA Zoology department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt College of Engineering and Technology American University of the Middle EastKuwaitKuwait

A recent study by Zoufaly et *** in The Lancet Respiratory Medicine describes encouraging data from the first severe COVId-19 patient successfully treated with human recombinant soluble angiotensin-converting enzyme-2(hrsACE2).1 The published data document upon treatment of an adaptive immune response,the disappearance of the virus swiftly from the serum,the nasal cavity and lungs,and a reduction of inflammatory cytokine levels that are critical for COVId-19 ***,the use of hrsACE2 did not impede the generation of neutralizing antibodies,leading to a significant clinical improvement of the treated patient.

关键词： ACE2 al cavity