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Role of lipids in virus assembly

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889195824 Year: Pages: 91 DOI: 10.3389/978-2-88919-582-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Microbiology --- Botany
Added to DOAB on : 2016-03-10 08:14:32
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RNA enveloped viruses comprise several families belonging to plus and minus strand RNA viruses, such as retroviruses, flavoviruses and orthomyxoviruses. Viruses utilize cellular lipids during critical steps of replication like entry, assembly and egress. Growing evidence indicate important roles for lipids and lipid nanodomains in virus assembly. This special topic covers key aspects of virus-membrane interactions during assembly and egress, especially those of retroviruses and Ebola virus (EBOV). Virus assembly and release involve specific and nonspecific interactions between viral proteins and membrane compartments. Retroviral Gag proteins assemble predominantly on the PM. Despite the great progress in identifying the factors that modulate retroviral Gag assembly on the PM, there are still gaps in our understanding of precise mechanisms of Gag-membrane interactions. Studies over the last two decades have focused on the mechanisms by which other retroviral Gag proteins interact with membranes during assembly. These include human immunodeficiency virus (HIV), Rous sarcoma virus (RSV), equine infectious anemia virus (EIAV), Mason-Pfizer monkey virus (M-PMV), murine leukemia virus (MLV), and human T-lymphotropic virus type (HTLV-1). Additionally, assembly of filoviruses such as EBOV also occurs on the inner leaflet of the PM. The articles published under this special topic highlight the latest understanding of the role of membrane lipids during virus assembly, egress and release.

Keywords

retroviruses --- HIV 1 --- Gag --- Matrix --- membrane --- NMR --- Ebola --- VP40

Modelling the human cardiac fluid mechanics. 2nd ed

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ISBN: 3866440871 Year: Pages: 39 p. DOI: 10.5445/KSP/1000005151 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:01:58
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In the second edition of the article a virtual heart modelsimulating the flow in the active left human ventricle andatrium is presented. Because in vivo myocardium data is notavailable, the movement of the active ventricle and its atriumis given by three-dimensional, time-dependent invivo image dataof a nuclear spin MRI tomograph. The passive part of the virtualheart model consists of a model aorta and of two-dimensionallymodelled heart valves. As the flow is actively driven by theventricle and atrium, a coupling off low and structure isnecessary to take into account the deviation of the aorta andthe closing and opening of the heart valves. This coupling isreplaced by the movement given by MRI tomograph and ultrasonicDoppler echocardiography, since we focus on the flow simulationin the left pumping ventricle. The flow simulation is performedby a validated commercial software package that uses the finitevolume method. The flow resistance of the circulation throughthe body is taken into account with a simplified circulationmodel. The article shows how the virtual heart model can be usedto predict flow losses and flow structures due to pathologicalventricle contraction defects. It provides as an example theflow simulation of an unhealthy human ventricle with ananeurysm. The flow structure and flow losses are consideredbefore and after surgery.

Untersuchungen zur Struktur und zur Beladungskinetik von Tiefenfiltern

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ISBN: 3937300619 Year: Pages: XV, 195 p. DOI: 10.5445/KSP/1000003485 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Chemical Engineering
Added to DOAB on : 2019-07-30 20:01:58
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Die Tiefenfiltration ist für all jene technischen Anwendungen ein klassisches Verfahren zur Abscheidung von Partikeln aus Fluiden, bei welchen die Partikeln nur in mäßiger Konzentration von einigen mg/m3 vorkommen oder der Druckverlust sehr gering sein soll (VDI 3677 Blatt 2). In dieser Arbeit werden Messmethoden und Modelle entwickelt, die zur zukünftigen Simulation der Filtrationskinetik von Faserfiltermedien benötigt werden.Zum einen ist es notwendig, a priori die lokale Packungsdichte in einer Filterprobe zu kennen, um spätere Simulationen und Experimente für dieselbe Probe überprüfen zu können. Dies wird mit der neu entwickelten und verifizierten Methode zur Bestimmung der lokalen Packungsdichte innerhalb einer Filterprobe, basierend auf der mit quantitativer MRI gemessenen Faserstruktur, nun möglich. Weiterhin wird die hierfür notwendige Auflösung bestimmt sowie der Einfluss der Anordnung der lokalen Packungsdichten als auch der Einfluss der Zellengröße auf die Vorhersage des Druckverlustes mittels des in der Filtertechnik üblichen Zellenmodells untersucht.Zum anderen ist ein detailliertes Verständnis der Mikrophänomene bei der Beladung einzelner Fasern notwendig, da sich die Filterperformance aufgrund der abgeschiedenen Partikeln ändert. Hierzu ist, wie die Literaturübersicht zeigt, noch wenig bekannt. Daher wurde das CFD Programm FLUENT durch User-Defined-Functions so erweitert, dass der Aufbau von Partikelstrukturen an einzelnen Fasern unter Berücksichtigung des Sperreffekts als auch des Einflusses der abgeschiedenen Partikeln auf die Strömung sowie durch Modellierung von Haften bzw. Abprallen erstmals wirklichkeitsnah durchgeführt werden kann. Es wird gezeigt, dass eine qualitativ gute Übereinstimmung der Partikelstruktur mit experimentellen Ergebnissen anderer Arbeiten erzielt wird. Die Möglichkeit der Simulation erlaubt es dann, gezielt den Einfluss der Partikelhaftung auf die Morphologie und mittleren Packungsdichte der Partikelstruktur sowie auf die Änderung von Abscheidegrad und Druckverlust mit zunehmender Anzahl abgeschiedener Partikeln zu untersuchen. In weiteren Simulationen wird für monodisperse Latex- und Kalksteinpartikeln bei kleineren Stokeszahlen ein vertieftes Verständnis der Filtrationskinetik an Einzelfasern gewonnen. In einem Ausblick wird abschließend die mögliche Anwendung der neuen Routinen zur Simulation des Clogging von Faserstrukturen aufgezeigt.

Transcellular Cycles Underlying Neurotransmission

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196548 Year: Pages: 105 DOI: 10.3389/978-2-88919-654-8 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2016-08-16 10:34:25
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Synaptic transmission demands the operation of a highly specialized metabolic machinery involving the transfer of metabolites and neurotransmitters between neurons, astrocytes and microvessels. In the last years, important advances have occurred in our understanding of the mechanisms underlying cerebral activation, neuroglial coupling and the associated neurovascular response. Briefly, exacerbated oxygen consumption in stimulated neurons is thought to trigger glycolytic lactate and glucose transfer from astrocytes which, in turn, obtain these fuels from the microvasculature. Neurotransmitter release is made possible by a combination of transcellular cycles exchanging metabolites between these three compartments, returning eventually the synapsis to its pre-firing situation in the resting periods. In spite of the enormous progresses achieved in recent years, the drivers determining the predominant direction of the fluxes, their quantitative contribution and their energy requirements, have remained until today incompletely understood, more particularly under the circumstances prevailing in vivo. In many instances, progress derived from the implementation of novel methodological approaches including advanced neuroimaging and neurospectroscopy methods. As a consequence, literature in the field became vast, diverse and spread within journals of different specialities. The e-book "Transcellular cycles underlying neurotransmission" aims to summaryze in a single volume, recent progress achieved in hypothesis, methods and interpretations on the trafficking of metabolites between neurons and glial cells, and the associated mechanisms of neurovascular coupling.

Glycan Diversity in Fungi, Bacteria and Sea Organisms

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889199426 Year: Pages: 85 DOI: 10.3389/978-2-88919-942-6 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Internal medicine
Added to DOAB on : 2016-01-19 14:05:46
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The cell surface of fungi, bacteria and sea organisms is highly glycosylated. These glycans are oligo- or polysaccharide molecules that can be secreted or attached to protein or lipids forming glycoconjugates. They present extraordinary structural diversity that could explain their involvement in many fundamental cellular processes, including growth, differentiation and morphogenesis. Considerable advances have been made on the structural elucidation of these glycans. Their primary structures were determined based on a combination of mass spectrometry and NMR spectroscopy techniques. The combination of these sensitive and powerful techniques has allowed us to increase our structural knowledge of a wide variety of glycans expressed by different fungi, bacteria and sea organisms.

Organophosphorus Chemistry 2018

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ISBN: 9783039282364 9783039282371 Year: Pages: 601 DOI: 10.3390/books978-3-03928-237-1 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General) --- Organic Chemistry
Added to DOAB on : 2020-04-07 23:07:08
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Organophosphorus chemistry is an important discipline within organic chemistry. Phosphorus compounds, such as phosphines, trialkyl phosphites, phosphine oxides (chalcogenides), phosphonates, phosphinates and >P(O)H species, etc., may be important starting materials or intermediates in syntheses. Let us mention the Wittig reaction and the related transformations, the Arbuzov- and the Pudovik reactions, the Kabachnik–Fields condensation, the Hirao reaction, the Mitsunobu reaction, etc. Other reactions, e.g., homogeneous catalytic transformations or C-C coupling reactions involve P-ligands in transition metal (Pt, Pd, etc.) complex catalysts. The synthesis of chiral organophosphorus compounds means a continuous challenge. Methods have been elaborated for the resolution of tertiary phosphine oxides and for stereoselective organophosphorus transformations. P-heterocyclic compounds, including aromatic and bridged derivatives, P-functionalized macrocycles, dendrimers and low coordinated P-fragments, are also of interest. An important segment of organophosphorus chemistry is the pool of biologically-active compounds that are searched and used as drugs, or as plant-protecting agents. The natural analogue of P-compounds may also be mentioned. Many new phosphine oxides, phosphinates, phosphonates and phosphoric esters have been described, which may find application on a broad scale. Phase transfer catalysis, ionic liquids and detergents also have connections to phosphorus chemistry. Green chemical aspects of organophosphorus chemistry (e.g., microwave-assisted syntheses, solvent-free accomplishments, optimizations, and atom-efficient syntheses) represent a dynamically developing field. Last, but not least, theoretical approaches and computational chemistry are also a strong sub-discipline within organophosphorus chemistry.

Lipopolysaccharides (LPSs)

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ISBN: 9783039282562 9783039282579 Year: Pages: 390 DOI: 10.3390/books978-3-03928-257-9 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General) --- Allergy and Immunology
Added to DOAB on : 2020-04-07 23:07:08
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The cytoplasm of Gram-negative bacteria is bound by three layers: an inner membrane, a layer of peptidoglycan, and an outer membrane. The outer membrane is an asymmetric lipidic bilayer, with phospholipids on its inner surface and lipopolysaccharides (LPSs) on the outside, with the latter being the major component of the outer leaflet and covering nearly three-quarters of the total outer cell surface. All LPSs possess the same general chemical architecture independently of bacterial activity (pathogenic, symbiotic, commensal), ecological niche (human, animal, soil, plant, water), or growth conditions. Endotoxins are large amphiphilic molecules consisting of a hydrophilic polysaccharide component and a covalently bound hydrophobic and highly conserved lipid component, termed lipid A (the endotoxin subunit). The polysaccharide component can be divided into two subdomains: the internal and conserved core region as well as the more external and highly variable O-specific chain, also referred to as the O-antigen due to its immunogenic properties. LPSs are endotoxins, one of the most potent class of activators of the mammalian immune system; they can be released from cell surfaces of bacteria during multiplication, lysis, and death. LPS can act through its biological center (lipid A component) on various cell types, of which macrophages and monocytes are the most important.

Keywords

aspirin --- hepcidin --- P65 (nuclear factor-?B) --- IL-6/JAK2/STAT3 pathway --- lipopolysaccharide (LPS) --- nitric oxide (NO) --- iron regulatory protein 1 (IRP1) --- Megalobrama amblycephala --- lipopolysaccharide induced TNF? factor --- lipopolysaccharide stimulation --- innate immune --- Aeromonas --- genomics --- inner core oligosaccharide --- outer core oligosaccharide --- lipopolysaccharide --- lipopolysaccharide --- Erwinia amylovora --- NMR --- ESI FT-ICR --- structural determination --- Bordetellae --- Bordetella holmesii --- endotoxin --- lipid A --- structure --- mass spectrometry --- genomic --- Edwardsiella tarda --- core oligosaccharide --- MALDI-TOF MS --- ESI MSn --- NMR --- genomic --- LPS tolerance --- hypothalamic inflammation --- insulin resistance --- pJNK --- fibroblast --- keratocyte --- cornea --- lipopolysaccharide --- bacteria --- chemokine --- adhesion molecule --- collagen --- tear fluid --- serum resistance --- complement --- Salmonella --- lipopolysaccharide --- sialic acid --- reptile-associated salmonellosis --- sepsis --- time response --- inflammation --- oxidative stress --- endotoxaemia --- mouse --- rat --- lipopolysaccharide --- double-stranded RNA --- epithelial cell --- dendritic cell --- allergic respiratory disorder --- hygiene hypothesis --- rhinovirus --- respiratory syncytial virus --- toll-like receptor --- LPS --- lipopolysaccharide --- heptosyltransferase --- protein dynamics --- glycosyltransferase --- GT-B --- inhibitor design --- lipopolysaccharide --- Coxiella burnetii --- Q fever --- phagosome --- virenose --- Plesiomonas shigelloides --- O-antigen --- lipopolysaccharide --- O-acetylation --- d-galactan I --- HR-MAS --- NMR spectroscopy --- endotoxin --- lipopolysaccharide --- Low Endotoxin Recovery --- phase transitions --- polysorbate --- LPS aggregates --- Small Angle X-ray Scattering --- MAT --- LAL and LER --- anti-conjugate serum --- core oligosaccharide --- lipopolysaccharide --- NMR spectroscopy --- ESI MS --- Proteus penneri

Wine Traceability

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ISBN: 9783039217687 9783039217694 Year: Pages: 138 DOI: 10.3390/books978-3-03921-769-4 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Biochemistry
Added to DOAB on : 2019-12-09 11:49:16
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Wine traceability is a central theme in the current world market where consumers are increasingly demanding the quality and origin of food and drink. The wine production chain and wine composition are generally controlled by different laws (International Organization of Vine and Wine (OIV), European Union (EU), and national governments) and need specific documentation. Nevertheless, wine production is subject to fraud. Consequently, the improvement of the methods applied to verify the origin and quality of wines is very important to protect wine consumers and producers. In this book, eight different papers—six research papers and two reviews—address the topic from different points of view.

Special Issue Dedicated to Late Professor Takuo Okuda. Tannins and Related Polyphenols Revisited: Chemistry, Biochemistry and Biological Activities

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ISBN: 9783038978343 9783038978350 Year: Pages: 316 DOI: 10.3390/books978-3-03897-835-0 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-06-26 10:09:00
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Antioxidative polyphenols represented by tannins and flavonoids are rich in numerous food sources and traditional natural medicines and currently attracting increased attention in health care and food industries because of their multiple biological activities that are favorable to human health. Commemorating the outstanding achievements on tannins by Dr. Takuo Okuda on the occasion of his passing away in December 2016, his colleagues, friends, and worldwide experts of polyphenol research have contributed 18 papers on their recent study to the Special Issue of Molecules. This book is its reprinted form. This covers reviews of structural features, historical usages, and biological activities of unique class of ellagitannins and condensed tannins, and original articles on the most up-to-date findings on the anticancer effect of green tea catechins, the antivirus effect of tannins comparing with the clinically used drugs, the analytical method of ellagitannins using quantitative NMR, the chemical structures of Hydrangea-blue complex (pigment) and condensed tannins in Ephedra sinica and purple prairie clover, and the relationship of condensed tannins in legumes and grape-marc with methane production in the in vitro ruminant system, and others. This book will be useful to natural product chemists and also to researchers in pharmaceutical and/or food industry.

Keywords

Dittrichia viscosa --- antifungal activities --- Candida spp. --- Malassezia spp. --- Microsporum canis --- Aspergillus fumigates --- Ephedra sinica --- proanthocyanidin --- oligomer --- thiolysis --- phloroglucinolysis --- TDDFT --- ECD --- neuraminidase --- inhibition --- tannins --- oseltamivir carboxylate --- zanamivir --- crystal structure --- molecular interactions --- oenothein B --- ellagitannin --- macrocyclic oligomer --- Onagraceae --- Myrtaceae --- Lythraceae --- antioxidants --- antitumor effect --- immunomodulatory effect --- anti-inflammation --- tannin composition --- purple prairie clover --- conservation method --- protein precipitation --- Escherichia coli --- Cynanchum wilfordii --- phenolic glycoside --- 2-O-?-laminaribiosyl-4-hydroxyacetophenone --- cynandione A --- thin layer chromatography --- Cynanchum auriculatum --- Acacia mearnsii bark --- wattle tannin --- proanthocyanidins --- biological activities --- tannins --- vegetable tanning --- European historic leathers --- colorimetric tests --- spectroscopy --- UV-Vis --- FTIR --- triple-negative breast cancer --- fatty acid synthase --- FASN inhibition --- polyphenolic FASN inhibitors --- (?)-epigallocatechin 3-gallate --- synthetic analogues --- apoptosis --- anticancer activity --- 1H-NMR --- quantitative NMR --- ellagitannin --- Geranium thunbergii --- geraniin --- Aluminum ion --- blue color development --- 5-O-caffeoylquinic acid --- 3-O-glucosyldelphinidin --- Hydrangea macrophylla --- ESI-mass --- metal complex --- Coreopsis lanceolata L. --- chalcone --- flavanone --- flavonol --- aurone --- Horner–Wadsworth–Emmons reaction --- condensed tannin --- bioactivity --- methanogenesis --- grape marc --- fatty acids --- in vitro batch fermentation --- neuroprotection --- PC12 --- NGF --- differentiation --- amyloid-? peptide --- taxanes --- hormesis --- polyphenol --- bamboo leaf extract --- overlay method --- ellagitannin --- structure --- revision --- (?)-epigallocatechin gallate --- immune checkpoint --- interferon-? --- epidermal growth factor --- lung tumor --- proanthocyanidins --- condensed tannins --- thiolysis --- NMR spectroscopy --- ultrahigh-resolution negative mode MALDI-TOF mass spectrometry --- antioxidant --- ORAC assay --- Acacia --- forage legume --- Trapa taiwanensis Nakai --- hydrolysable tannin --- stability --- gallotannin --- ellagitannin

Looking Forward to the Future of Heparin: New Sources, Developments and Applications

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ISBN: 9783038429494 9783038429500 Year: Pages: 282 DOI: 10.3390/books978-3-03842-950-0 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-08-28 11:21:28
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Abstract

This book is a printed edition of the Special Issue Looking Forward to the Future of Heparin: New Sources, Developments and Applications that was published in Molecules

Keywords

thrombin inhibition --- LMWH --- antithrombin --- heparin oligosaccharides --- ternary complex --- heparin --- hepcidin --- iron homeostasis --- anemia --- heparin-induced thrombocytopenia --- diagnosis --- functional assay --- platelets --- heparin --- heparan sulphate --- TGF-? --- bone morphogenetic protein (BMP) --- growth and differentiation factor (GDF) --- GDNF --- BMP antagonists --- noggin --- sclerostin --- gremlin --- heparin --- enoxaparin --- subarachnoid hemorrhage --- edema --- brain injury --- inflammation --- cisplatin --- low molecular weight heparin (LMWH) --- ovarian cancer --- resistance --- heparin --- glycosaminoglycans --- chondroitin sulfate --- perylene diimide dyes --- dermatan sulfate --- fluorescent probe --- Heparin Red --- assay --- dermatan sulfate --- human plasma --- heparin --- alginate --- sulfated alginate --- biomaterials --- heparin --- heparan sulfate --- serglycin --- proteoglycan --- recombinant expression --- bioreactor --- theranostics --- solid lipid nanoparticles --- iron oxide nanoparticles --- heparin coating --- intestinal lymphatic absorption --- heparin --- heparin process --- manufacturing methods --- industrial --- super paramagnetic iron oxide nanoparticles (SPION) --- hyaluronic acid (HA) --- bovine serum albumin (BSA) --- Fe3O4·DA-BSA/HA --- paclitaxel (PTX) --- magnetic resonance imaging (MRI) --- low-molecular-weight heparin --- dalteparin --- NMR --- LC-MS --- affinity chromatography --- danaparoid sodium --- low molecular weight glycosaminoglycans --- orthogonal multi-analytical methods --- sequence and compositional investigations --- component quantitative analysis --- heparin --- crude heparin --- NMR --- quantitative NMR --- PCA --- chemometric --- HSQC --- bovine heparin --- porcine heparin --- molecular weight --- size exclusion chromatography --- pharmacopeia --- Fondaparinux sodium --- extended physicochemical characterization --- qNMR --- single crystal X-ray structure --- reference standard --- iduronic acid conformation --- Arixtra® --- n/a --- n/a --- n/a

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