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Ink-structing the future of vascular tissue engineering:a review of the physiological bioink design

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Bio-Design and Manufacturing 2024年第2期7卷 181-205页

作者： Judith Synofzik Sebastian Heene rebecca Jonczyk cornelia Blume Institute for Technical chemistry Leibniz University Hannover30167 HannoverGermany

Three-dimensional(3D)printing and bioprinting have come into view for a plannable and standardizable generation of implantable tissue-engineered constructs that can substitute native tissues and *** tissue-engineered structures are intended to integrate with the patient’s *** tissue engineering(TE)is relevant in TE because it supports the sustained oxygenization and nutrition of all tissue-engineered *** have a specific role,representingthenecessarymedium for printability and vascular cell *** review aims to understand the requirements for the design of vascular ***,an in-depth analysis of vascular cell interaction with their native environment must be gained.A physiological bioink suitable for a tissue-engineered vascular graft(TEVG)must not only ensure good printability but also induce cells to behave like in a native vascular vessel,including self-regenerative and growth *** review describes the general structure of vascular walls with wall-speciﬁc cell and extracellular matrix(EcM)components and biomechanical properties and ***,the physiological role of vascular EcM components for their interaction with vascular cells and the mode of interaction is *** currently available or imaginable bioinks are described from physiological matrix proteins to nonphysiologically occurring but natural chemical compounds useful for vascular *** physiological performance of these bioinks is evaluated with regard to biomechanical properties postprinting,with a view to current animal studies of 3D printed vascular ***,the main challenges for further bioink development,suitable bioink components to create a self-assembly bioink concept,and future bioprinting strategies are *** concepts are discussed in terms of their suitability to be part of a TEVG with a high potential for later clinical use.

关键词： Vascular wall histology Vascular cells Microenvironment Extracellular matrix cell–matrix interaction Bioink Printability

A general method for assaying homo-and hetero-transglycanase activities that act on plant cell-wall polysaccharides

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Journal of Integrative Plant Biology 2015年第4期57卷 411-428页

作者： Lenka Franková Stephen c.fry The Edinburgh cell Wall Group Institute of Molecular Plant SciencesThe University of EdinburghDaniel Rutherford BuildingThe King's Buildings

Transglycanases（endotransglycosylases） cleave a polysaccharide（donor-substrate） in mid-chain, and then transfer a portion onto another poly-or oligosaccharide（acceptor-substrate）. Such enzymes contribute to plant cellwall assembly and/or re-structuring. We sought a general method for revealing novel homo- and hetero-transglycanases, applicable to diverse polysaccharides and oligosaccharides, separating transglycanase-generated3 Hpolysaccharides from unreacted3H-oligosaccharides—the former immobilized（on filter-paper, silica-gel or glassfiber）,the latter eluted. On filter-paper, certain polysaccharides [e.g.（1!3, 1!4）-b-D-glucans] remained satisfactorily adsorbed when water-washed; others（e.g. pectins） were partially lost. Many oligosaccharides（e.g. arabinan-, galactan-, xyloglucan-based） were successfully eluted in appropriate solvents, but others（e.g. [3H]xylohexaitol, [3H]mannohexaitol[3H]cellohexaitol） remained immobile. On silica-gel, all3 Holigosaccharides left an immobile ‘ghost’ spot（contaminating any3H-polysaccharides）, which was diminished but not prevented by additives e.g. sucrose or Triton X-100. The best stratum was glassfiber（GF）, onto which the reactionmixture was dried then washed in 75% ethanol. Washing led to minimal loss or lateral migration of3H-polysaccharides if conducted by slow percolation of acidified ethanol. The effectiveness of GF-blotting was well demonstrated for chara vulgaris transb-mannanase. In conclusion, our novel GF-blotting technique ef ficiently frees transglycanase-generated3H-polysaccharides from unreacted3H-oligosaccharides,enabling high-throughput screening of multiple postulated transglycanase activities utilising chemically diverse donorand acceptor-substrates.

关键词： Glass-fiber blotting plant cell wall polysaccharides(donor) radiolabeled oligosaccharides (acceptor) transglycanase

The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells:An example of metabolic plasticity

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Journal of Integrative Plant Biology 2015年第4期57卷 373-387页

作者： María de castro Janice G.Miller José Luis Acebes Antonio Encina Penélope García-Angulo Stephen c.fry The Edinburgh cell Wall Group Institute of Molecular Plant SciencesSchool of Biological SciencesDaniel Rutherford BuildingThe King's Buildings Laboratory of Plant Physiology Faculty of Biological and Environmental SciencesUniversity of Léon

cell-suspension cultures（Zea mays L.,Black Mexican sweet corn） habituated to 2,6-dichlorobenzonitrile（DcB） survive with reduced cellulose owing to hemicellulose network modification. We aimed to de fine the hemicellulose metabolism modifications in DcB-habituated maize cells showing a mild reduction in cellulose at different stages in the culture cycle. Using pulse-chase radiolabeling, we fed habituated and non-habituated cultures with [3H]arabinose,and traced the distribution of 3H-pentose residues between xylans, xyloglucans and other polymers in several cellular compartments for 5 h. Habituated cells were slower taking up exogenous [3H]arabinose. Tritium was incorporated into polysaccharide-bound arabinose and xylose residues, but habituated cells diverted a higher proportion of their new [3H]xylose residues into（hetero） xylans at the expense of xyloglucan synthesis. During logarithmic growth, habituated cells showed slower vesicular traf ficking of polymers,especially xylans. Moreover, habituated cells showed a decrease in the strong wall-binding of all pentose-containing polysaccharides studied; correspondingly, especially in log phase cultures, habituation increased the proportion of 3H-hemicelluloses（[3H]xylans and [3H]xyloglucan） sloughed into the medium. These findings could be related to the cel walls’ cellulose-deficiency, and consequent reduction in binding sites for hemicelluloses; the data could also re fl ect the habituated cells’ reduced capacity to integrate arabinox ylans by extra-protoplasmic phenolic cross-linking, as well as xyloglucans, during wall assembly.

关键词： Arabinoxylan cell wall cross-linking 2,6-dichlorobenzonitrile Hemicellulose biosynthesis xyloglucan

Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells

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Journal of Integrative Plant Biology 2017年第7期59卷 475-495页

作者： María de castro Romina Martínez-Rubio José L.Acebes Antonio Encina Stephen c.fry Penélope García-Angulo área de Fisiología Vegetal.Dpto.Ingenieríay ciencias Agrarias.Facultad de Biologíay ciencias Ambientales.Universidad de León The Edinburgh cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences Daniel Rutherford BuildingThe King's Buildings

As a consequence of the habituation to low levels of dichlobenil （DcB）, cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase in soluble extracellular polymers released into the culture medium. The aim of this study was to investigate the relative molecular mass distributions of polysaccharides as well as phenolic metabolism in cells habituated to low levels of DcB （1.5 μM）. Generally, cell wall bound hemicelluloses and sloughed polymers from habituated cells were more homogeneously sized and had a lower weight-average relative molecular mass. In addition, polysaccharides underwent massive cross-linking after being secreted into the cell wall, but this cross-linking was less pronounced in habituated cells than in non-habituated ones. However, when relativized, ferulic acid and p-coumaric acid contents were higher in this habituated cell line. Feasibly, cells habituated to low levels of DcB synthesized molecules with a lower weight-average relative molecular mass, although cross-linked, as a part of their strategy to compensate for the lack of cellulose.

关键词： Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells were for

Hetero-trans-β-Glucanase Produces cellulose-Xyloglucan covalent Bonds in the cell Walls of Structural Plant Tissues and Is Stimulated by Expansin

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Molecular Plant 2020年第7期13卷 1047-1062页

作者： Klaus Herburger Lenka Frankova Martina Picmanova Jia Wooi Loh Marcos Valenzuela-Ortega Frank Meulewaeter Andrew D.Hudson christopher E.French Stephen c.fry The Edinburgh cell Wall Group Institute of Molecular Plant SciencesSchool of Biological SciencesThe University of EdinburghEdinburgh EH93BFUnited Kingdom Institute of Quantitative Biology Biochemistry and BiotechnologySchool of Biological SciencesThe University of EdinburghEdinburgh EH93BFUnited Kingdom BASF BBCC Innovation Center Gent-Trait Research9052 Gent(Zwijnaarde)Belgium Zhejiang University-University of Edinburgh Joint Research centre for Engineering Biology Zhejiang UniversityHainingZhejiang 314400China Present address:Section for Plant Glycobiology Department of Plant and Environmental SciencesUniversity of CopenhagenFrederiksberg 1871Denmark

current cell-wall models assume no covalent bonding between cellulose and hemicelluloses such as xyloglu-can or mixed-linkageβ-D-glucan(MLG).However,Equisetum hetero-trans-β-glucanase(HTG)grafts cellu-lose onto xyloglucan oligosaccharides(XGOs)-and,we now show,xyloglucan polysaccharide-in vitro,thus exhibiting cXE(cellulose:xyloglucan endotransglucosylase)*** addition,HTG also catalyzes MLG-to-XGO bonding(MXE activity).In this study,we explored the cXE action of HTG in native plant cell walls and tested whether expansin exposes cellulose to HTG by disrupting hydrogen *** quantify and visu-alize cXE and MXE action,we assayed the sequential release of HTG products from cell walls pre-labeled with substrate *** demonstrated covalent cellulose--xyloglucan bonding in plant cell walls and showed that cXE and MXE action was up to 15%and 60%of total transglucanase action,respectively,and peaked in aging,strengthening tissues:cXE in xylem and cells bordering intercellular canals and MXE in *** bacterial expansin(EXLX1)strongly augmented cXE activity in *** and MXE ac-tion in living Equisetum structural tissues potentially strengthens stems,while expansin might augment the HTG-catalyzed cXE reaction,thereby allowing efficient cXE action in *** methods will enable surveys for comparable reactions throughout the plant ***,engineering similar hetero-polymer formation into angiosperm crop plants may improve certain agronomic traits such as lodging tolerance.

关键词： cell wall cellulose hemicelluloses hetero-trans-p-glucanase hetero-transglycosylation xyloglucan

Frequency of the c677T Polymorphism of MTHFR, G20210A of Prothrombin and R506Q of Factor V Leiden in Type 2 Diabetics in Abidjan

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Open Journal of Genetics 2024年第1期14卷 13-25页

作者： N’Guessan-Blao rebecca Yapo Vincent Yayo-Ayé Mireille Adjambri Eusèbe Koné-Koné Fatoumata Sawadogo Duni Hematology and General Biology Unit Faculty of Pharmaceutical and Biological Sciences Department of Biological Sciences Felix Houphouet-Boigny University Abidjan Ivory Coast Laboratory of Biology and Medical Research National Institute of Public Health (INSP) Abidjan Ivory Coast Molecular Biology Unit Center for Diagnosis and Research on AIDS and Other Infectious Diseases (CeDReS) Treichville University Hospital (CHU) Abidjan Ivory Coast

In Africa, the prevalence of diabetes is escalating and remains a concern due to the numerous complications it causes. Vascular damage associated with diabetes leads to a prothrombotic state observed in diabetic individuals. Diabetes is a complex and multifactorial disease involving genetic components. With the aim of preventing complications and contributing to an efficient management of diabetes, we investigated genes likely to lead to a risk of thrombosis, in particular the c677T of MTHFR, G20210A of prothrombin, and R506Q of factor V Leiden in type 2 diabetics in Abidjan receiving ambulatory care. A descriptive cross-sectional study was carried out on consenting type 2 diabetic patients. Mutation detection was carried out using the PcR-RFLP method employing restriction enzymes. Hemostasis tests (fibrinogen, D-dimers, fibrin monomers, and von Willebrand factor) were performed using citrate tubes on the Stage? Star Max automated system. Plasminogen activator inhibitor was assayed by ELISA method, and biochemical parameters were determined using the cOBAS c311. The study population consisted of 45 diabetic patients, 51.1% of whom presented vascular complications, mainly neuropathy. Disturbances in hemostasis parameters were observed, with 15.5% of patients showing an increase in fibrin monomers. Mutation analysis revealed an absence of factor V mutation (factor V Leiden) and of G20210A mutation of the prothrombin gene. However, 15.6% of subjects had a heterozygous c677T mutation of MTHFR, with 57% of them being anemic. The exploration of biological and genetic factors associated with thrombotic risk is of significant interest in the optimal management of African type 2 diabetics.

关键词： Type 2 Diabetes c677T of MTHFR G20210A Factor V Leiden Thrombosis

Feruloylated Arabinoxylans Are Oxidatively cross- Linked by Extracellular Maize Peroxidase but Not by Horseradish Peroxidase

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Molecular Plant 2009年第5期2卷 883-892页

作者： Sally J. Burr Stephen c. fry The Edinburgh cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences The University of Edinburgh Daniel Rutherford Building The King's Buildings Edinburgh EH9 3JH UK Present address: Ecologie Microbienne/UMR cNRS 5557 USc INRA 1193 Universite Claude Bernard--Lyon 1 Batiment Gregor Mendel 16 rue Dubois F-69622 Villeurbanne Cedex France

covalent cross-linking of soluble extracellular arabinoxylans in living maize cultures, which models the cross- linking of wall-bound arabinoxylans, is due to oxidation of feruloyl esters to oligoferuloyl esters and ethers. The oxidizing system responsible could be H2O2/peroxidase, O2/laccase, or reactive oxygen species acting non-enzymically, To distinguish these possibilities, we studied arabinoxylan cross-linking in vivo and in vitro. In living cultures, exogenous, soluble, extracellular, feruloylated [pentosyl-3H]arabinoxylans underwent cross-linking, beginning abruptly 8 d after sub-culture. crosslinking was suppressed by iodide, an H2O2 scavenger, indicating dependence on endogenous H2O2. However, exogenous H2O2 did not cause precocious cross-linking, despite the constant presence of endogenous peroxidases, suggesting that younger cultures contained natural cross-linking inhibitors. Dialysed culture-filtrates cross-linked [^3H]arabinoxylans in vitro only if H2O2 was also added, indicating a peroxidase requirement. This cross-linking was highly ionic-strength-dependent. The peroxidases responsible were heat-labile, although relatively heat-stable peroxidases （assayed on o-dianisidine） were also present. Surprisingly, added horseradish peroxidase, even after heat-denaturation, blocked the arabinoxylancross-linking action of maize peroxidases, suggesting that the horseradish protein was a competing substrate for [^3H]arabinoxylan coupling. In conclusion, we show for the first time that cross-linking of extracellular arabinoxylan in living maize cultures is an action of apoplastic peroxidases, some of whose unusual properties we report.

关键词： cell wall cross-links phenolics ferulate peroxidase soluble extracellular polysaccharides Zea mays L.

challenges of modeling solar disturbances' arrival times at the Earth

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Science china(Technological Sciences) 2008年第10期51卷 1580-1588页

作者： c. D. fry chin-chun WU Murray DRYER center for Space Plasma and Aeronomic Research The University of Alabama in Huntsville Huntsville AL 35899 USA Exploration Physics International Inc. Huntsville AL 35806 USA center for Space Plasma and Aeronomic Research The University of Alabama in Huntsville Huntsville AL 35899 USA Space Weather Laboratory NASA/Goddard Space Flight Center Greenbelt MD 20771 USA center for Space Plasma and Aeronomic Research The University of Alabama in Huntsville Huntsville AL 35899 USA Exploration Physics International Inc. Huntsville AL 35806 USA Space Weather Prediction Center National Oceanic and Atmospheric Administration (NOAA) Boulder Colorado USA

In recent years remarkable advances have been made in the development of phys-ics based models of various parts of the solar-terrestrial system (see JASTP special issues, October, November 2004; February 2007). In this paper, we focus our dis-cussions in a specific region of the Sun to the Earth’s environment (i.e. 1 AU). It is well-known that geomagnetic storms are caused by solar eruptions. The conse-quences of these storms include particle acceleration, solar wind impact on the Earth’s magnetosphere and ionosphere, UV-EUV radiation effects on the lower at-mosphere, etc. One of the main challenges is to predict the arrival time at 1 AU of the solar disturbance. The prospects look good for an accurate, real-time forecast scheme built on the acquisition of solar, heliosphere and the near-Earth data and large-scale models. However, the accuracy of these models still needs improve-ment. We will discuss the present status of the models and challenges to improve the simulation models.

关键词： space weather――magnetohydrodynamic (MHD) Modeling MHD Sun-Earth connection MHD Sun-corona

Reconciling concepts, theory, and empirical patterns surrounding cascade reinforcement

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current Zoology 2016年第2期62卷 131-134页

作者： rebecca c. FULLER Department of Animal Biology University of Illinois Urbana IL 61801 USA

IntroductionReinforcement is a critically important process in speciation. It has been credited with often completing speciation, and it is unique in that natural selection directly favors the evolution of reproductive isolating barriers. Reinforcement occurs when selection favors increased prezygotic isolation between two lineages in order to avoid maladaptive hybridization in areas of sympatry （Noor 1999; Servedio and Noor 2003; coyne and Orr 2004）.

关键词：调和加固梯级