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Metals and neurodegeneration: Restoring the balance

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889197392 Year: Pages: 132 DOI: 10.3389/978-2-88919-739-2 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Science (General)
Added to DOAB on : 2016-04-07 11:22:02
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Biometals such as copper, zinc and iron have key biological functions, however, aberrant metabolism can lead to detrimental effects on cell function and survival. These biometals have important roles in the brain, driving cellular respiration, antioxidant activity, intracellular signaling and many additional structural and enzymatic functions. There is now considerable evidence that abnormal biometal homeostasis is a key feature of many neurodegenerative diseases and may have an important role in the onset and progression of disorders such as Alzheimer’s, Parkinson’s, prion and motor neuron diseases. Recent studies also support biometal roles in a number of less common neurodegenerative disorders. The role of biometals in a growing list of brain disorders is supported by evidence from a wide range of sources including molecular genetics, biochemical studies and biometal imaging. These studies have spurred a growing interest in understanding the role of biometals in brain function and disease as well as the development of therapeutic approaches that may be able to restore the altered biometal chemistry of the brain. These approaches range from genetic manipulation of biometal transport to chelation of excess metals or delivery of metals where levels are deficient. A number of these approaches are offering promising results in cellular and animal models of neurodegeneration with successful translation to pre-clinical and clinical trials. At a time of aging populations and slow progress in development of neurotherapeutics to treat age-related neurodegenerative diseases, there is now a critical need to further our understanding of biometals in neurodegeneration. This issue covers a broad range of topics related to biometals and their role in neurodegeneration. It is hoped that this will inspire greater discussion and exchange of ideas in this crucial area of research and lead to positive outcomes for sufferers of these neurodegenerative diseases.

First-Principles Approaches to Metals, Alloys, and Metallic Compounds

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ISBN: 9783038973584 9783038973591 Year: Pages: 180 DOI: 10.3390/books978-3-03897-359-1 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Mining and Metallurgy --- Chemistry (General)
Added to DOAB on : 2018-11-26 11:24:24
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Current fundamental electronic-structure theory allows for the accurate prediction and characterization of elemental metals adopting any allotropic structure, intermetallic compounds, and other metal-rich phases. From an engineering perspective, there is a need for structural materials that are suitable for mechanical and civil engineering as well as energy production and conversion. While different microstructural features influence the macroscopic behaviour, quantum-mechanical simulation may enormously accelerate and guide the entire development process since atomistic modelling allows for the generation of structural models and the calculation of enthalpies and other free energies as a function of pressure and temperature. Among other things, this volume covers high-manganese steels, some of which have come to light within Collaborative Research Centre 761 (“Steel ab initio”). In particular, it deals with short-range ordering from experiment and theory, also highlighting carbide-like precipitates, and it bridges the gap between atomistic and continuum levels, in particular for hydrogen embrittlement. Molecular dynamics simulates crack propagation, and first-principles theory helps in growing better intermetallic thin films and predicts structural and elastic properties. Eventually, multiscale modelling of hydrogen transport is provided, and the chemical reasons for H-trapping κ-carbides are highlighted. First-principles theory has acquired a powerful role in the fundamental and applied research of metals, alloys, and metallic compounds.

Recent Advances in Hydro- and Biohydrometallurgy

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ISBN: 9783039212996 / 9783039213009 Year: Pages: 212 DOI: 10.3390/books978-3-03921-300-9 Language: eng
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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This Special Issue of Minerals presents recent, select studies that highlight advances in the fields of hydro- and biohydrometallurgy. It aims to attract the interest of readers and especially of young scientists and students in this fascinating scientific discipline.

Molecular Magnets

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ISBN: 9783038977100 Year: Pages: 166 DOI: 10.3390/books978-3-03897-711-7 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-03-21 14:08:22
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Molecular magnets show many properties not met in conventional metallic magnetic materials, i.e. low density, transparency to electromagnetic radiation, sensitivity to external stimuli such as light, pressure, temperature, chemical modification or magnetic/electric fields, and others. They can serve as “functional” materials in sensors of different types or be applied in high-density magnetic storage or nanoscale devices. Research into molecule-based materials became more intense at the end of the 20th century and is now an important branch of modern science. The articles in this Special Issue, written by physicists and chemists, reflect the current work on molecular magnets being carried out in several research centers. Theoretical papers in the issue concern the influence of spin anisotropy in the low dimensional lattice of the resulting type of magnet, as well as thermodynamics and magnetic excitations in spin trimers. The impact of external pressure on structural and magnetic properties and its underlying mechanisms is described using the example of Prussian blue analogue data. The other functionality discussed is the magnetocaloric effect, investigated in coordination polymers and high spin clusters. In this issue, new molecular magnets are presented: (i) ferromagnetic high-spin [Mn6] single-molecule magnets, (ii) solvatomagnetic compounds changing their structure and magnetism dependent on water content, and (iii) a family of purely organic magnetic materials. Finally, an advanced calorimetric study of anisotropy in magnetic molecular superconductors is reviewed.

Smart Nanovesicles for Drug Targeting and Delivery

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ISBN: 9783038978947 / 9783038978954 Year: Pages: 198 DOI: 10.3390/books978-3-03897-895-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General) --- Therapeutics
Added to DOAB on : 2019-06-26 08:44:06
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Nanovesicles are highly-promising systems for the delivery and/or targeting of drugs, biomolecules and contrast agents. Despite the fact that initial studies in this area were performed on phospholipid vesicles, there is an ever-increasing interest in the use of other molecules to obtain smart vesicular carriers focusing on strategies for targeted delivery. These systems can be obtained using newly synthesized smart molecules, or by intelligent design of opportune carriers to achieve specific delivery to the site of action.

Asymmetric and Selective Biocatalysis

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ISBN: 9783038978466 9783038978473 Year: Pages: 154 DOI: 10.3390/books978-3-03897-847-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-06-26 09:16:44
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This Issue contains one communication, six articles, and two reviews. The communication from Paola Vitale et al. represents a work where whole cells were used as biocatalysts for the reduction of optically active chloroalkyl arylketones followed by a chemical cyclization to give the desired heterocycles. Among the various whole cells screened (baker’s yeast, Kluyveromyces marxianus CBS 6556, Saccharomyces cerevisiae CBS 7336, Lactobacillus reuteri DSM 20016), baker’s yeast provided the best yields and the highest enantiomeric ratios (95:5) in the bioreduction of the above ketones. In this respect, valuable chiral non-racemic functionalized oxygen-containing heterocycles (e.g., (S)-styrene oxide, (S)-2-phenyloxetane, (S)-2-phenyltetrahydrofuran), amenable to be further elaborated on, can be smoothly and successfully generated from their prochiral precursors. Studies about pure biocatalysts with mechanistical studies, application in different reactions, and new immobilization methods for improving their stability were reported in five different articles. The article by Su-Yan Wang et al. describes the cloning, expression, purification, and characterization of an N-acetylglucosamine 2-epimerase from Pedobacter heparinus (PhGn2E). For this, several N-acylated glucosamine derivatives were chemically synthesized and used to test the substrate specificity of the enzyme. The mechanism of the enzyme was studied by hydrogen/deuterium NMR. The study at the anomeric hydroxyl group and C-2 position of the substrate in the reaction mixture confirmed the epimerization reaction via ring-opening/enolate formation. Site-directed mutagenesis was also used to confirm the proposed mechanism of this interesting enzyme. The article by Forest H. Andrews et al. studies two enzymes, benzoylformate decarboxylase (BFDC) and pyruvate decarboxylase (PDC), which catalyze the non-oxidative decarboxylation of 2-keto acids with different specificity. BFDC from Pseudomonas putida exhibited very limited activity with pyruvate, whereas the PDCs from S. cerevisiae or from Zymomonas mobilis showed virtually no activity with benzoylformate (phenylglyoxylate). After studies using saturation mutagenesis, the BFDC T377L/A460Y variant was obtained, with 10,000-fold increase in pyruvate/benzoylformate. The change was attributed to an improvement in the Km value for pyruvate and a decrease in the kcat value for benzoylformate. The characterization of the new catalyst was performed, providing context for the observed changes in the specificity. The article by Xin Wang et al. compares two types of biocatalysts to produce D-lysine L-lysine in a cascade process catalyzed by two enzymes: racemase from microorganisms that racemize L-lysine to give D,L-lysine and decarboxylase that can be in cells, permeabilized cells, and the isolated enzyme. The comparison between the different forms demonstrated that the isolated enzyme showed the higher decarboxylase activity. Under optimal conditions, 750.7 mmol/L D-lysine was finally obtained from 1710 mmol/L L-lysine after 1 h of racemization reaction and 0.5 h of decarboxylation reaction. D-lysine yield could reach 48.8% with enantiomeric excess (ee) of 99%. In the article by Rivero and Palomo, lipase from Candida rugosa (CRL) was highly stabilized at alkaline pH in the presence of PEG, which permitted its immobilization for the first time by multipoint covalent attachment on different aldehyde-activated matrices. Different covalent immobilized preparation of the enzyme was successfully obtained. The thermal and solvent stability was highly increased by this treatment, and the novel catalysts showed high regioselectivity in the deprotection of per-O-acetylated nucleosides. The article by Robson Carlos Alnoch et al. describes the protocol and use of a new generation of tailor-made bifunctional supports activated with alkyl groups that allow the immobilization of proteins through the most hydrophobic region of the protein surface and aldehyde groups that allows the covalent immobilization of the previously adsorbed proteins. These supports were especially used in the case of lipase immobilization. The immobilization of a new metagenomic lipase (LipC12) yielded a biocatalyst 3.5-fold more active and 5000-fold more stable than the soluble enzyme. The PEGylated immobilized lipase showed high regioselectivity, producing high yields of the C-3 monodeacetylated product at pH 5.0 and 4 °C. Hybrid catalysts composed of an enzyme and metallic complex are also treated in this Special Issue. The article by Christian Herrero et al. describes the development of the Mn(TpCPP)-Xln10A artificial metalloenzyme, obtained by non-covalent insertion of Mn(III)-meso-tetrakis(p-carboxyphenyl)porphyrin [Mn(TpCPP), 1-Mn] into xylanase 10A from Streptomyces lividans (Xln10A). The complex was found able to catalyze the selective photo-induced oxidation of organic substrates in the presence of [RuII(bpy)3]2+ as a photosensitizer and [CoIII(NH3)5Cl]2+ as a sacrificial electron acceptor, using water as oxygen atom source. The two published reviews describe different subjects with interest in the fields of biocatalysis and mix metallic-biocatalysis, respectively. The review by Anika Scholtissek et al. describes the state-of-the-art regarding ene-reductases from the old yellow enzyme family (OYEs) to catalyze the asymmetric hydrogenation of activated alkenes to produce chiral products with industrial interest. The dependence of OYEs on pyridine nucleotide coenzyme can be avoided by using nicotinamide coenzyme mimetics. In the review, three main classes of OYEs are described and characterized. The review by Yajie Wang and Huimin Zhao highlights some of the recent examples in the past three years that combine transition metal catalysis with enzymatic catalysis. With recent advances in protein engineering, catalyst synthesis, artificial metalloenzymes, and supramolecular assembly, there is great potential to develop more sophisticated tandem chemoenzymatic processes for the synthesis of structurally complex chemicals. In conclusion, these nine publications give an overview of the possibilities of different catalysts, both traditional biocatalysts and hybrids with metals or organometallic complexes to be used in different processes—particularly in synthetic reactions—under very mild reaction conditions.

Application and Behavior of Nanomaterials in Water Treatment

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ISBN: 9783039211715 / 9783039211722 Year: Pages: 174 DOI: 10.3390/books978-3-03921-172-2 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Physics (General)
Added to DOAB on : 2019-12-09 11:49:15
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The book compiles scientific articles describing advances in nanomaterial synthesis and their application in water remediation. The publications treat diverse problems such as dye degradation, heavy metal ion, as well as radioactive element capture and sequestration. There are 10 original research articles and one review article. The latter proposes graphene/CNT and Prussian blue nanocomposites for radioactive 137-cesium extraction from aqueous media. All reports thoroughly characterize the nanomaterials post-synthesis and describe their catalytic, photocatalytic, or ion exchange activities in contaminated water. The dyes studied in the collection are azo dyes, i.e. methylene blue and orange, rhodamine B, phenolic dyes viz. bromophenol blue, and other dyes with sulfonyl groups. Extraction of radioactive elements, including cationic 137Cs+ and anionic 125I?, is also investigated. The omnipresence of ZnO nanoparticles in everyday products and their effects in wastewater are also evaluated. Layered double hydroxide are capable of capturing Ag ions, which then has a catalytic effect on dye degradation. The nanomaterials considered are varied, viz., graphene, CNT, Prussian blue, nanoporous carbon, layered double hydroxides, magnetite, ferrites, organic powders, polymer membranes, bacteria, and inorganic nanomaterials such as MnO and Ag. The book targets an interdisciplinary readership.

Efficiency of Bank Filtration and Post-Treatment

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ISBN: 9783039213054 / 9783039213061 Year: Pages: 352 DOI: 10.3390/books978-3-03921-306-1 Language: eng
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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Riverbank filtration (RBF) schemes for the production of drinking water are increasingly challenged by new constituents of concern, such as organic micropollutants and pathogens in the source water and hydrological flow variations due to weather extremes. RBF and new technology components are integrated and monitoring and operating regimes are adopted to further optimize water treatment in bank filtration schemes for these new requirements. This Special Issue presents results from the EU project AquaNES “Demonstrating synergies in combined natural and engineered processes for water treatment systems” (www.aquanes.eu). Additionally, papers from other research groups cover the efficiency of bank filtration and post-treatment, advantages and limitations of combining natural and engineered processes, parameter-specific assessment of removal rates during bank filtration, and the design and operation of RBF wells. The feasibility, design, and operation of RBF schemes under specific site conditions are highlighted for sites in the US, India, and South Korea

Keywords

riverbank filtration --- removal efficacy --- dissolved organic carbon (DOC) --- pesticides --- pharmaceutical residues --- riverbank filtration --- organic matter degradation --- manganese --- riverbed --- climate change --- floods --- droughts --- column experiments --- PHREEQC --- decentralized capillary nanofiltration --- anoxic --- suboxic --- organic micropollutants --- bank filtrate --- groundwater --- sulphate --- dissolved organic matter --- high temperature --- sub-oxic conditions --- organic matter composition --- PARAFAC-EEM --- LC-OCD --- redox sensitivity --- micropollutants --- oxypurinol --- gabapentin --- river bank filtration --- hydrological trends --- sustainable water production --- well structure remodeling --- point-bar alluvial setting --- riverbank filtration --- site investigation --- hydrochemistry --- subsurface geology --- riverbank filtration --- organic micropollutants --- water quality --- environmental monitoring --- riverbank filtration --- collector wells --- performance --- entrance velocity --- river bank filtration --- attenuation --- organic micropollutants --- pharmaceuticals --- riverbank filtration --- small communities --- disinfection by-products --- trihalomethanes --- riverbank filtration (RBF) --- Krishna River --- southern India --- water treatment --- water quality --- salinity --- river bank filtration --- ultrafiltration --- surface water treatment --- energy efficiency --- out/in membrane comparison --- inline electrolysis --- bank filtration --- biofilm --- clogging --- filter cake --- pathogen barrier --- pressure loss --- slow sand filtration --- electro-chlorination --- smart villages --- disinfection --- river bank filtration --- rural water supply, online monitoring --- dissolved organic matter --- fluorescence excitation-emission matrix --- LC-OCD --- Nakdong River --- riverbank filtration --- bank filtration --- drinking water treatment --- inorganic chemicals --- organic micropollutants --- Ganga --- Yamuna --- Damodar --- riverbank filtration --- water quality --- organic carbon --- nitrate --- heavy metals --- microorganisms --- riverbank filtration --- riverside water source --- analytical method --- mirror-image method --- optimization --- riverbank filtration --- water quality --- bank filtrate portion --- iron --- manganese --- microorganisms --- system costs --- water supply --- storage tank --- drinking water hydropower --- turbine --- energy generation --- renewable energy

Plasma Catalysis

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ISBN: 9783038977506 Year: Pages: 246 DOI: 10.3390/books978-3-03897-751-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Chemical Engineering --- Technology (General)
Added to DOAB on : 2019-04-05 10:34:31
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Plasma catalysis is gaining increasing interest for various gas conversion applications, such as CO2 conversion into value-added chemicals and fuels, N2 fixation for the synthesis of NH3 or NOx, methane conversion into higher hydrocarbons or oxygenates. It is also widely used for air pollution control (e.g., VOC

TRP Channels in Health and Disease

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ISBN: 9783039210824 / 9783039210831 Year: Pages: 266 DOI: 10.3390/books978-3-03921-083-1 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-06-26 08:44:07
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Almost 25 years ago, the first mammalian transient receptor potential (TRP) channel was cloned and published. TRP channels now represent an extended family of 28 members fulfilling multiple roles in the living organism. Identified functions include control of body temperature, transmitter release, mineral homeostasis, chemical sensing, and survival mechanisms in a challenging environment. The TRP channel superfamily covers six families: TRPC with C for “canonical”, TRPA with A for “ankyrin”, TRPM with M for “melastatin”, TRPML with ML for “mucolipidin”, TRPP with P for “polycystin”, and TRPV with V for “vanilloid”. Over the last few years, new findings on TRP channels have confirmed their exceptional function as cellular sensors and effectors. This Special Book features a collection of 8 reviews and 7 original articles published in “Cells” summarizing the current state-of-the-art on TRP channel research, with a main focus on TRP channel activation, their physiological and pathophysiological function, and their roles as pharmacological targets for future therapeutic options.

Keywords

ion channel --- TRPC --- small molecules --- calcium --- chemical probes --- TRPV1 --- TRPV2 --- TRPV3 --- TRPV4 --- mucosal epithelium --- ulcerative colitis --- inflammatory bowel disease --- TRPM4 channel --- cardiovascular system --- physiology --- pathophysiology --- TRPC6 --- elementary immunology --- inflammation --- calcium --- sodium --- neutrophils --- lymphocytes --- endothelium --- platelets --- human medulla oblongata --- cuneate nucleus --- dorsal column nuclei --- TRPV1 --- calcitonin gene-related peptide --- substance P --- TRP channels --- calcium signaling --- salivary glands --- xerostomia --- radiation --- inflammation --- transient receptor potential channels --- TRPC3 pharmacology --- channel structure --- lipid mediators --- photochromic ligands --- transient receptor potential --- TRPC3 --- mGluR1 --- GABAB --- EPSC --- Purkinje cell --- cerebellum --- toxicology --- TRP channels --- organ toxicity --- chemicals --- pollutants --- chemosensor --- TRPM7 --- kinase --- inflammation --- lymphocytes --- calcium signalling --- SMAD --- TH17 --- hypersensitivity --- regulatory T cells --- thrombosis --- graft versus host disease --- 2D gel electrophoresis --- AP18 --- HEK293 --- HSP70 --- MALDI-TOF MS(/MS) --- nanoHPLC-ESI MS/MS --- proteomics --- sulfur mustard --- TRPA1 --- TRPC channels --- diacylglycerol --- TRPC4 --- TRPC5 --- NHERF --- TRP channel --- TRPY1 --- Saccharomyces cerevisiae --- calcium --- manganese --- oxidative stress --- ion channels --- overproduction --- production platform --- protein purification --- Saccharomyces cerevisiae --- sensors --- transient receptor potential (TRP) channels --- yeast --- adipose tissue --- bioavailable --- menthol --- topical --- TRPM8 --- n/a

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