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The role of arginase in endothelial dysfunction

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194407 Year: Pages: 115 DOI: 10.3389/978-2-88919-440-7 Language: English
Publisher: Frontiers Media SA
Subject: Allergy and Immunology --- Medicine (General)
Added to DOAB on : 2016-02-05 17:24:33
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In recent years, an increasing number of manuscripts have been published addressing the deleterious role of arginase in endothelial dysfunction. ROS have been shown to play a crucial role in arginase activation, which in turn leads to eNOS dysfunction.

Ways to improve tumor uptake and penetration of drugs into solid tumors

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889193509 Year: Pages: 129 DOI: 10.3389/978-2-88919-350-9 Language: English
Publisher: Frontiers Media SA
Subject: Oncology --- Medicine (General) --- Therapeutics --- Science (General)
Added to DOAB on : 2016-03-10 08:14:32
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The main scope of this topic is to give an update on pharmacologic and non-pharmacologic approaches to enhance uptake and penetration of cancer drugs into tumors. Inadequate accumulation of drugs in tumors has emerged over the last decade as one of the main problems underlying therapeutic failure and drug resistance in the treatment of cancer. Insufficient drug uptake and penetration is causally related to the abnormal tumor architecture. Thus, poor vascularization, increased resistance to blood flow and impaired blood supply represent a first obstacle to the delivery of antitumor drugs to tumor tissue. Decreased or even inverted transvascular pressure gradients compromise convective delivery of drugs. Eventually, an abnormal extracellular matrix offers increased frictional resistance to tumor drug penetration. Abnormal tumor architecture also changes the biology of tumor cells, which contributes to drug resistance through several different mechanisms. The variability in vessel location and structure can make many areas of the tumor hypoxic, which causes the tumor cells to become quiescent and thereby resistant to many antitumor drugs. In addition, the abnormally long distance of part of the tumor cell population from blood vessels provides a challenge to delivering cancer drugs to these cells. We have recently proposed additional mechanisms of tumor drug resistance, which are also related to abnormal tumor architecture. First, increased interstitial fluid pressure can by itself induce drug resistance through the induction of resistance-promoting paracrine factors. Second, the interaction of drug molecules with vessel- proximal tumor cell layers may also induce the release of these factors, which can spread throughout the cancer, and induce drug resistance in tumor cells distant from blood vessels. As can be seen, abnormal tumor architecture, inadequate drug accumulation and tumor drug resistance are tightly linked phenomena, suggesting the need to normalize the tumor architecture, including blood vessels, and/or increase the accumulation of cancer drugs in tumors in order to increase therapeutic effects. Indeed, several classes of drugs (that we refer to as promoter drugs) have been described, that promote tumor uptake and penetration of antitumor drugs, including those that are vasoactive, modify the barrier function of tumor vessels, debulk tumor cells, and overcome intercellular and stromal barriers. In addition, also non-pharmacologic approaches have been described that enhance tumor accumulation of effector drugs (e.g. convection-enhanced delivery, hyperthermia, etc.). Some drugs that have already received regulatory approval (e.g. the anti-VEGF antibody bevacizumab) exert antitumor effects at least in part through normalization of the tumor vasculature and enhancement of the accumulation of effector drugs. Other drugs, acting through different mechanisms of action, are now in clinical development (e.g. NGR-TNF in phase II/III studies) and others are about to enter clinical investigation (e.g. JO-1).

Gastrointestinal Variables and Drug Absorption: Experimental, Computational and In Vitro Predictive Approaches

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ISBN: 9783039284924 9783039284931 Year: Pages: 206 DOI: 10.3390/books978-3-03928-493-1 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General) --- Therapeutics
Added to DOAB on : 2020-04-07 23:07:09
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This book presents some of the state-of-the-art methods for the study of the gastrointestinal variables affecting oral drug absorption. Practical applications of new in vitro release/dissolution methods are presented, as well as in vitro permeability studies to explore segmental differences. The application of MRI methods for the study of colon physiology is presented to illustrate its potential applications in controlled release dosage form design. Some examples of successful in vitro–in vivo correlations show how implementing the gastrointestinal physiological variables in the new in vitro methods can improve the predictions of in vivo drug product performance. The book contains an updated review of the experimental, computational, and in vivo approaches for measuring intestinal permeability.

Stimuli-Responsive Polymer Systems—Recent Manufacturing Techniques and Applications

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ISBN: 9783039214839 9783039214846 Year: Pages: 92 DOI: 10.3390/books978-3-03921-484-6 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-12-09 11:49:15
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Stimuli-responsive polymer systems can be defined as functional materials that show physical or chemical property changes in response to external stimuli such as temperature, radiation, chemical agents, pH, mechanical stress, and electric and magnetic fields. Recent developments in manufacturing techniques have facilitated the production of a wide range of stimuli-responsive polymer systems, such as micro- and nanoscale structures, with potential applications in soft sensors and actuators, smart textiles, soft robots, and artificial muscles. This book brings together the recent progress in manufacturing techniques, with particular emphasis on 3D and 4D printing and applications of stimuli-responsive polymer systems in biomedicine and soft robotics.

Improved Reservoir Models and Production Forecasting Techniques for Multi-Stage Fractured Hydrocarbon Wells

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ISBN: 9783039218929 9783039218936 Year: Pages: 238 DOI: 10.3390/books978-3-03921-893-6 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2020-01-07 09:08:26
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The massive increase in energy demand and the related rapid development of unconventional reservoirs has opened up exciting new energy supply opportunities along with new, seemingly intractable engineering and research challenges. The energy industry has primarily depended on a heuristic approach—rather than a systematic approach—to optimize and tackle the various challenges when developing new and improving the performance of existing unconventional reservoirs. Industry needs accurate estimations of well production performance and of the cumulative estimated ultimate reserves, accounting for uncertainty. This Special Issue presents 10 original and high-quality research articles related to the modeling of unconventional reservoirs, which showcase advanced methods for fractured reservoir simulation, and improved production forecasting techniques.

Flow and Transport Properties of Unconventional Reservoirs 2018

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ISBN: 9783039211166 9783039211173 Year: Pages: 364 DOI: 10.3390/books978-3-03921-117-3 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-08-28 11:21:27
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Unconventional reservoirs are usually complex and highly heterogeneous, such as shale, coal, and tight sandstone reservoirs. The strong physical and chemical interactions between fluids and pore surfaces lead to the inapplicability of conventional approaches for characterizing fluid flow in these low-porosity and ultralow-permeability reservoir systems. Therefore, new theories and techniques are urgently needed to characterize petrophysical properties, fluid transport, and their relationships at multiple scales for improving production efficiency from unconventional reservoirs. This book presents fundamental innovations gathered from 21 recent works on novel applications of new techniques and theories in unconventional reservoirs, covering the fields of petrophysical characterization, hydraulic fracturing, fluid transport physics, enhanced oil recovery, and geothermal energy. Clearly, the research covered in this book is helpful to understand and master the latest techniques and theories for unconventional reservoirs, which have important practical significance for the economic and effective development of unconventional oil and gas resources.

Keywords

fracturing fluid --- rheology --- chelating agent --- viscosity --- polymer --- fluid-solid interaction --- velocity profile --- the average flow velocity --- flow resistance --- pore network model --- shale gas --- volume fracturing --- finite volume method --- production simulation --- multi-scale flow --- multi-scale fracture --- shale gas reservoir --- fractured well transient productivity --- succession pseudo-steady state (SPSS) method --- complex fracture network --- multi-scale flow --- analysis of influencing factors --- tight sandstones --- spontaneous imbibition --- remaining oil distributions --- imbibition front --- imbibition recovery --- NMR --- slip length --- large density ratio --- contact angle --- pseudo-potential model --- lattice Boltzmann method --- micro-fracture --- dissolved gas --- experimental evaluation --- reservoir depletion --- recovery factor --- tight oil --- Lucaogou Formation --- tight oil --- pore structure --- prediction by NMR logs --- tight oil reservoir --- SRV-fractured horizontal well --- multiporosity and multiscale --- flow regimes --- productivity contribution degree of multimedium --- equilibrium permeability --- non-equilibrium permeability --- matrix–fracture interaction --- effective stress --- coal deformation --- porous media --- non-linear flow --- conformable derivative --- fractal --- hydraulic fracturing --- tight reservoirs --- fracture diversion --- extended finite element method --- fracture network --- gas adsorption capacity --- shale reservoirs --- influential factors --- integrated methods --- sulfonate gemini surfactant --- thickener --- temperature-resistance --- clean fracturing fluid --- low-salinity water flooding --- clay mineral composition --- enhanced oil recovery --- wetting angle --- pH of formation water --- fractional diffusion --- fractal geometry --- analytical model --- shale gas reservoir --- carbonate reservoir --- petrophysical characterization --- pore types --- pore structure --- permeability --- fractal dimension --- reservoir classifications --- deep circulation groundwater --- groundwater flow --- geothermal water --- faults --- isotopes --- shale permeability --- local effect --- global effect --- matrix-fracture interactions --- nanopore --- pore structure --- shale --- tight sandstone --- mudstone --- nitrogen adsorption --- fractal --- enhanced geothermal system --- well-placement optimization --- fracture continuum method --- 0-1 programming --- unconventional reservoirs --- petrophysical characterization --- fluid transport physics

Mathematical Modeling of Fluid Flow and Heat Transfer in Petroleum Industries and Geothermal Applications

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ISBN: 9783039287208 / 9783039287215 Year: Pages: 470 DOI: 10.3390/books978-3-03928-721-5 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2020-06-09 16:38:57
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Geothermal energy is the thermal energy generated and stored in the Earth's core, mantle, and crust. Geothermal technologies are used to generate electricity and to heat and cool buildings. To develop accurate models for heat and mass transfer applications involving fluid flow in geothermal applications or reservoir engineering and petroleum industries, a basic knowledge of the rheological and transport properties of the materials involved (drilling fluid, rock properties, etc.)—especially in high-temperature and high-pressure environments—are needed. This Special Issue considers all aspects of fluid flow and heat transfer in geothermal applications, including the ground heat exchanger, conduction and convection in porous media. The emphasis here is on mathematical and computational aspects of fluid flow in conventional and unconventional reservoirs, geothermal engineering, fluid flow, and heat transfer in drilling engineering and enhanced oil recovery (hydraulic fracturing, CO2 injection, etc.) applications.

Keywords

dynamic hydraulic-fracturing experiments --- dynamic crack tip --- fluid front kinetics --- energy conservation analysis --- cost-effective --- frequency conversion technology (FCT) --- ventilation --- methane removal --- computational fluid dynamic (CFD) --- spatiotemporal characteristics --- capacitance-resistance model --- aquifer support --- inter-well connectivity --- production optimization --- karst carbonate reservoir --- tight reservoir --- huff-‘n-puff --- fracture simulation --- enhanced oil recovery --- CO2 diffusion --- percolation model --- fractal theory --- microstructure --- critical porosity --- conductivity --- permeability --- tight oil reservoirs --- fracture compressibility --- numerical simulation --- flowback --- fracture uncertainty --- enhanced geothermal systems --- multiple parallel fractures --- semi-analytical solution --- main gas pipeline --- pressure fluctuations --- unsteady process --- multifractal theory --- fractal theory --- pore structure --- mercury intrusion porosimetry --- pore size distribution --- natural gas --- pipeline network --- continuity/momentum and energy equations coupled --- efficient simulation --- enhanced gas recovery --- longitudinal dispersion coefficient --- injection orientation --- supercritical CO2 --- CO2 permeability --- Coal excavation --- coal and rock fracture --- multiple structural units (MSU) --- energy dissipation --- AE energy --- cement --- non-Newtonian fluids --- rheology --- variable viscosity --- diffusion --- underground coal gasification (UCG) --- economics --- cost of electricity (COE) --- techno-economic model --- methanol --- ammonia --- carbon capture and storage (CCS) --- carbon capture and utilization (CCU) --- electricity generation --- process simulation --- fractal --- slippage effect --- Knudsen diffusion --- surface diffusion --- apparent permeability --- wellbore temperature --- bottom-hole pressure --- multi-pressure system --- comprehensive heat transfer model --- leakage and overflow --- GSHP (ground source heat pump) --- heat transfer --- coupled heat conduction and advection --- nest of tubes --- three-dimensional numerical simulation --- sloshing --- real-scale --- highly viscous fluids --- Navier-Stokes equations --- impact pressure --- flowback --- complex fracture network --- shale oil --- porous media --- fractal theory --- particles model --- permeability --- tube bundle model --- cement slurries --- non-Newtonian fluids --- rheology --- constitutive relations --- viscosity --- yield stress --- thixotropy --- mathematical modeling --- computational fluid dynamics (CFD) --- drilling --- porous media --- multiphase flow --- hydraulic fracturing --- geothermal --- enhanced oil recovery

Transmucosal Absorption Enhancers in the Drug Delivery Field

Authors: --- ---
ISBN: 9783039218486 9783039218493 Year: Pages: 406 DOI: 10.3390/books978-3-03921-849-3 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Therapeutics --- Medicine (General)
Added to DOAB on : 2020-01-30 16:39:46
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Development of strategies to assist the movement of poorly permeable molecules across biological barriers has long been the goal of drug delivery science. In the last three decades, there has been an exponential increase in advanced drug delivery systems that aim to address this issue. However, most proprietary delivery technologies that have progressed to clinical development are based on permeation enhancers (PEs) that have a history of safe use in man. This Special Issue entitled “Transmucosal Absorption Enhancers in the Drug Delivery Field” aims to present the current state-of-the-art in the application of PEs to improve drug absorption. Emphasis is placed on identification of novel permeation enhancers, mechanisms of barrier alteration, physicochemical properties of PEs that contribute to optimal enhancement action, new delivery models to assess PEs, studies assessing safety of PEs, approaches to assist translation of PEs into effective oral, nasal, ocular and vaginal dosage forms and combining PEs with other delivery strategies.

Keywords

absorption enhancers --- sugar-based surfactants --- biocompatibility studies --- transmucosal drug delivery --- intestinal permeation enhancers --- sodium cholate (NaC) --- N-dodecyl-?-D-maltoside (DDM) --- small intestine --- enterocyte --- brush border --- tryptophan --- oral delivery --- insulin --- GLP-1 --- intestinal absorption --- amino acid --- cell-penetrating peptide --- combined microsphere --- chitosan --- cyclodextrin --- nasal delivery --- nose to brain transport --- penetration enhancer --- nasal formulation --- in vivo studies --- nose to brain delivery --- antiepileptic drug --- drug delivery --- block copolymers --- thermogel system --- chitosan derivatives --- amphiphilic polymers --- polymeric micelles --- quaternization --- curcumin --- intestinal delivery --- mucoadhesiveness --- cervicovaginal tumors --- cationic functionalization --- imatinib --- nanocrystals --- in situ hydrogel --- bioenhancer --- cytochrome P450 --- drug absorption enhancer --- efflux --- metabolism --- P-glycoprotein --- pharmacokinetic interaction --- tight junction --- Aloe vera --- gel --- whole leaf --- absorption enhancement --- Caco-2 --- confocal laser scanning microscopy --- F-actin --- FITC-dextran --- tight junctions --- transepithelial electrical resistance --- permeation enhancer --- oral delivery --- formulation --- permeability --- safety --- simulated intestinal fluid --- hydrophobization --- epithelium --- compound 48/80 --- chitosan --- nanoparticles --- mast cell activator --- vaccine adjuvant --- nasal vaccination --- absorption enhancer --- antimicrobial peptide --- Caco-2 --- claudin --- cell-penetrating peptide (CPP) --- drug delivery --- intestinal epithelial cells --- KLAL --- PN159 --- tight junction modulator --- oral macromolecule delivery --- oral peptides --- sodium caprate --- salcaprozate sodium --- epithelial permeability --- epithelial transport --- nasal permeability --- nose-to-brain --- simvastatin --- nanocapsules --- mucoadhesion --- CNS disorders --- chitosan --- nasal --- pulmonary --- drug administration --- absorption enhancers --- nanoparticle --- and liposome --- absorption enhancer --- gemini surfactant --- intestinal absorption --- poorly absorbed drug --- Caco-2 cells --- PTH 1-34 --- teriparatide --- nasal delivery --- pharmacokinetics --- osteoporosis --- man --- sheep --- clinical trial --- preclinical --- Caco-2 --- intestinal absorption --- nanomedicine --- nanoparticle --- oral delivery --- transferrin --- ocular drug delivery --- cornea --- penetration enhancers --- ocular conditions --- ophthalmology --- permeation enhancers --- absorption modifying excipients --- oral delivery --- nasal delivery --- ocular delivery --- vaginal delivery --- transmucosal permeation

Electrospun and Electrosprayed Formulations for Drug Delivery

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ISBN: 9783038979128 9783038979135 Year: Pages: 190 DOI: 10.3390/books978-3-03897-913-5 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General) --- Therapeutics
Added to DOAB on : 2019-06-26 10:09:00
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This book is comprised of important reviews and cutting-edge original research papers concerning electrospun and electrosprayed formulations in drug delivery. Electrospinning and electrospraying have, in recent years, attracted increasing attention in the pharmaceutical sector, with research in the area advancing rapidly. It is now possible to prepare extremely complex systems using multi-fluid processes, and to increase production rates to an industrial scale. Electrospun formulations can be produced under GMP conditions and are in clinical trials. In this volume, we explore a range of topics around electrospinning and electrospraying in controlled drug delivery. Four reviews cover the exciting potential of cyclodextrin-containing fibers and the many potential biomedical applications of electrospun fibers. The use of electrospinning to prepare amorphous systems and improve the dissolution rate and solubility of poorly soluble active ingredients is addressed, and the possibilities of such materials in tissue engineering are comprehensively covered. The six original research papers cover the effect of molecular properties on API release from Eudragit-based electrospun fibers; ferulic acid solid dispersions; electrospun medicines to treat psoriasis; scale up of electrospinning and its use to produce low-dose tablets; transepithelial permeation of drugs released from electrospun fibers, and the possibilities for the synergistic chemophotothermal treatment of cancer.

Development and Application of Herbal Medicine from Marine Origin

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ISBN: 9783039212217 9783039212224 Year: Pages: 140 DOI: 10.3390/books978-3-03921-222-4 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-08-28 11:21:27
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Marine herbal medicine generally refers to the use of marine plants as original materials to develop crude drugs, or for other medical purposes. The term ‘marine plants’ usually denotes macroalgae grown between intertidal and subintertidal zones, including Chlorophyta, Phaeophyta, and Rhodophyta. Considerable progress has been made in the field of biomedical research into marine microalgae and microorganisms in the past decade. As the most important source of fundamental products in the world, marine plants have a very important role in biomedical research. Furthermore, worldwide studies have consistently demonstrated that many crude drugs derived from marine plants contain novel ingredients that may benefit health or can be used in the treatment of diseases; some have been developed into health foods, and some even into drugs. It is expected that there are many substances of marine plant origin that will have medical applications in terms of improving human health and are awaiting discovery.In this Special Issue, entitled “Development and Application of Herbal Medicine of Marine Origin”, we will provide a platform for researchers to publish biomedical studies on substances of marine plant origin. We welcome submissions from scientists and academics from across the world.

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