538,173 results match your criteria reactions

The scope of flavin-dependent reactions and processes in the model plant Arabidopsis thaliana.

Phytochemistry 2021 Jun 9;189:112822. Epub 2021 Jun 9.

Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria. Electronic address:

Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are utilized as coenzymes in many biochemical reduction-oxidation reactions owing to the ability of the tricyclic isoalloxazine ring system to employ the oxidized, radical and reduced state. We have analyzed the genome of Arabidopsis thaliana to establish an inventory of genes encoding flavin-dependent enzymes (flavoenzymes) as a basis to explore the range of flavin-dependent biochemical reactions that occur in this model plant. Expectedly, flavoenzymes catalyze many pivotal reactions in primary catabolism, which are connected to the degradation of basic metabolites, such as fatty and amino acids as well as carbohydrates and purines. Read More

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Generation of hydroxyl radicals by metal-free bifunctional electrocatalysts for enhanced organics removal.

Sci Total Environ 2021 May 31;791:148107. Epub 2021 May 31.

Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China. Electronic address:

Low yields of HO and a narrow range of appropriate pH values have been two major drawbacks for electro-Fenton (EF) process. Herein, metal-free electrochemical advanced oxidation processes (EAOPs) were developed with nitrogen and sulfur co-doped electrochemically exfoliated graphene (N, S-EEGr) electrocatalysts, which was confirmed as an outstanding bifunctional catalyst for synchronous generation and activation of HO via (2 + 1) e consecutive reduction reactions. Specifically, two elements (N, S) in metal-free N, S-EEGr-CF cathode synergize to promote the formation of HO followed by its activation. Read More

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In-situ reconstruction of non-noble multi-metal core-shell oxyfluorides for water oxidation.

J Colloid Interface Sci 2021 May 31;602:55-63. Epub 2021 May 31.

School of Materials Science and Engineering, Jiangsu Key Laboratory of Advanced Metallic Materials, Southeast University, Nanjing 211189, China. Electronic address:

The electrochemical anodic behavior of transition metal compounds plays an undeniably non-negligible role across many electrooxidation reactions. In this work, a chronopotentiometric technique was employed to activate the multicomponent non-noble metal oxyfluorides in-situ for oxygen evolution reaction (OER). It is interesting to unravel that the increasing applied current density helps to reconstruct the catalyst into nanoporous core-shell structure and introduce metal oxyhydroxide on the surface, which guarantees more channels for efficient ion/mass transportation and thus contributes to exposing more active sites for catalytic reaction. Read More

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Temporal responses of hydrochemical variables and dissolved Fe(II) to flooding at a lake riparian wetland under different vegetation revealing by high resolution DGT.

J Environ Manage 2021 Jun 9;294:112930. Epub 2021 Jun 9.

Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China.

The interplay between hydrological and biogeochemical processes in riparian wetland was recognized to lead directly to the temporal variations of surface water quality. However, the effects of flooding and vegetation on the release and entrapment of heavy metals and nutrients in riparian wetland remain poorly understood. The study aimed at investigating the influences of flooding and vegetation on the hydrochemical and Fe-redox change in the soil porewater and shallow groundwater, in Poyang lake riparian wetland through hydrochemical monitoring and diffusive gradient technology (DGT). Read More

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Anti-seizure activity of African medicinal plants: the identification of bioactive alkaloids from the stem bark of Rauvolfia caffra using an in vivo zebrafish model.

J Ethnopharmacol 2021 Jun 9:114282. Epub 2021 Jun 9.

Department of Pharmaceutical Sciences, Tshwane University of Technology, Pretoria, South Africa, 0001. Electronic address:

Ethnopharmacological Relevance: Epilepsy is one of the major chronic diseases that does not have a cure to date. Adverse drug reactions have been reported from the use of available antiepileptic drugs (AEDs) which are also effective in only two-thirds of the patients. Accordingly, the identification of scaffolds with promising anti-seizure activity remains an important first step towards the development of new anti-epileptic therapies, with improved efficacy and reduced adverse effects. Read More

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The murburn precepts for aerobic respiration and redox homeostasis.

Prog Biophys Mol Biol 2021 Jun 9. Epub 2021 Jun 9.

Institute of Chemical Kinetics and Combustion Russian Academy of Sciences, St. Institutskaya 3, 630090, Novosibirsk, Russia. Electronic address:

Murburn concept is a new perspective to metabolism which posits that certain redox enzymes/proteins mediate catalysis outside their active site, via diffusible reactive oxygen species (DROS, usually deemed as toxic wastes). We have recently questioned the proton-centric chemiosmotic rotary ATP synthesis (CRAS) explanation for mitochondrial oxidative phosphorylation (mOxPhos) and proposed an oxygen-centric murburn model in lieu. Herein, the chemical equations and thermodynamic foundations for this new model of mOxPhos are detailed. Read More

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Versatile Reaction Pathways of 1,1,3,3,3-pentafluoropropene at Rh(I) complexes [Rh(E)(PEt3)3] (E = H, GePh3, Si(OEt)3, F, Cl): C-F versus C-H Bond Activation Steps.

Chemistry 2021 Jun 12. Epub 2021 Jun 12.

Humboldt-Universitat zu Berlin, Department of Chemistry, GERMANY.

The reaction of the rhodium(I) complexes [Rh(E)(PEt 3 ) 3 ] (E = GePh 3 ( 1 ), H ( 6 ), F ( 7 )) with 1,1,3,3,3-pentafluoropropene afforded the defluorinative germylation products Z/E -2-(triphenylgermyl)-1,3,3,3-tetrafluoropropene and the fluorido complex [Rh(F)(CF 3 CHCF 2 )(PEt 3 ) 2 ] ( 2 ) together with the fluorophosphorane E -(CF 3 )CH=CF(PFEt 3 ). For [Rh(Si(OEt) 3 )(PEt 3 ) 3 ] ( 4 ) the coordination of the fluoroolefin was found  to give [Rh{Si(OEt) 3 }(CF 3 CHCF 2 )(PEt 3 ) 2 ] ( 5 ). Two equivalents of complex 2 reacted further by C-F bond oxidative addition to yield [Rh(CF=CHCF 3 )(PEt 3 ) 2 ( µ -F) 3 Rh(CF 3 CHCF 2 )(PEt 3 )] ( 9 ). Read More

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A hierarchical deep learning based approach for multi-functional enzyme classification.

Protein Sci 2021 Jun 12. Epub 2021 Jun 12.

Computational Biology Research Lab, National University of Computer and Emerging Sciences, Islamabad, Pakistan.

Enzymes are critical proteins in every organism. They speed up essential chemical reactions, help fight diseases and have a wide use in the pharmaceutical and manufacturing industries. Wet lab experiments to figure out an enzyme's function are time consuming and expensive. Read More

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Synthesis and Evaluation of F-Labeled Fluoroalkyl Triphenylphosphonium Salts as Mitochondrial Voltage Sensors in PET Myocardial Imaging.

Methods Mol Biol 2021 ;2275:49-64

Innovation Center for Molecular Probe Development, Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, Hwasun, South Korea.

We have previously reported that radiolabeled phosphonium cations accumulate in the mitochondria down a transmembrane potential gradient. We present an optimized procedure for synthesis of three [F]-labeled fluoroalkyl triphenylphosphonium salts ([F]FATPs) via two-step simple nucleophilic substitution reactions to develop new myocardial imaging agents for positron emission tomography (PET) . The total reaction time of [F]FATPs was within 60 min, and the overall decay-corrected radiochemical yield was approximately 15-30% (decay corrected). Read More

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January 2021

Oxidative formation of bis-N-methylquinolinone from anti-head-to-head N-methylquinolinone cyclodimer.

Photochem Photobiol Sci 2021 Jun 12. Epub 2021 Jun 12.

Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032, Marburg, Germany.

The light-driven formation and cleavage of cyclobutane structural motifs resulting from [2 + 2]-pericyclic reactions, as found in thymine and coumarin-type systems, is an important and intensively studied photochemical reaction. Various applications are reported utilizing these systems, among others, in cross-linked polymers, light-triggered drug release, or other technical applications. Herein coumarin is most frequently used as the photoactive group. Read More

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Efficacy and safety of TAS-115, a novel oral multi-kinase inhibitor, in osteosarcoma: an expansion cohort of a phase I study.

Invest New Drugs 2021 Jun 12. Epub 2021 Jun 12.

Department of Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Japan.

Background osteosarcoma is a rare, primary malignant bone tumour with limited available treatments for advanced or recurrent disease, resulting in a poor prognosis for patients. TAS-115 is a novel tyrosine kinase inhibitor under investigation in a phase I study in patients with solid tumours. We report data of osteosarcoma patients in the expansion cohort of this ongoing study. Read More

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A review on the computational studies of the reaction mechanisms of CO conversion on pure and bimetals of late 3d metals.

J Mol Model 2021 Jun 12;27(7):200. Epub 2021 Jun 12.

Department of Basic Sciences, University of Health and Allied Sciences, Ho, Ghana.

Despite series of experimental studies that reveal unique activities of late 3d transition metals and their role in microorganisms known for CO conversion, these surfaces are not industrially viable yet. An insight into the elementary steps of surface catalytic processes is crucial for effective surface modification and design. The mechanisms of CO transformation into CO, through the reverse water gas shift and methane reforming, are being studied. Read More

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Spatially Selective Imaging of Mitochondrial MicroRNAs via Optically Programmable Strand Displacement Reactions.

Angew Chem Int Ed Engl 2021 Jun 12. Epub 2021 Jun 12.

National Center for Nanoscience and Technology, CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, 11 ZhongGuanCun BeiYiTiao, Haidian District, 100190, Beijing, CHINA.

MicroRNA (miRNA) functions are tightly regulated by their sub-compartmental location in living cells, and the ability to imaging of mitochondrial miRNAs (mitomiRs) is essential for understanding of the related pathological processes. However, most existing DNA-based methods could not be used for this purpose. Here, we report the development of a DNA nanoreporter technology for imaging of mitomiRs in living cells through near-infrared (NIR) light-controlled DNA strand displacement reactions. Read More

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Metal Sulfide Photocatalysts for Lignocellulose Valorization.

Adv Mater 2021 Jun 12:e2007129. Epub 2021 Jun 12.

State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.

Transition metal sulfides are an extraordinarily vital class of semiconductors with a wide range of applications in the photocatalytic field. A great number of recent advances in photocatalytic transformations of lignocellulosic biomass, the largest renewable carbon resource, into high-quality fuels and value-added chemicals has been achieved over metal sulfide semiconductors. Herein, the progress and breakthroughs in metal-sulfide-based photocatalytic systems for lignocellulose valorization with an emphasis on selective depolymerization of lignin and oxidative coupling of some important bioplatforms are highligted. Read More

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WormPaths: Caenorhabditis elegans metabolic pathway annotation and visualization.

Genetics 2021 Jun 12. Epub 2021 Jun 12.

Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, 01609, United States of America.

In our group, we aim to understand metabolism in the nematode Caenorhabditis elegans and its relationships with gene expression, physiology and the response to therapeutic drugs. Visualization of the metabolic pathways that comprise the metabolic network is extremely useful for interpreting a wide variety of experiments. Detailed annotated metabolic pathway maps for C. Read More

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Anodic Olefin Coupling Reactions: Elucidating Radical Cation Mechanisms and the Interplay between Cyclization and Second Oxidation Steps.

Chem Rec 2021 Jun 11. Epub 2021 Jun 11.

Department of Chemistry, Washington University in Saint Louis, One Brookings Drive, 63130-4899, St Louis, MO, USA.

Anodic olefin coupling reactions generate new bonds and ring skeletons through a net two electron process that reverses the polarity of a known, electron-rich functional group. While much of the early work on the mechanism of these reactions focused on the initial oxidation and cyclization steps of the process, the second oxidation step also plays a central role in determining the success of the reaction. Evidence supporting this observation is presented, along with evidence that optimization of this second oxidation step is not enough to pull a poor cyclization to the desired product. Read More

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Confinement of Zinc Salt in Ultrathin Heterogeneous Film to Stabilize Zinc Metal Anode.

Small 2021 Jun 12:e2100722. Epub 2021 Jun 12.

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.

Aqueous zinc metal batteries (AZMBs) have drawn great attention due to the high theoretical capacity, low redox potential, and abundance reserves. However, the practical application of rechargeable AZMBs are hindered by the poor reversibility of Zn metal anode, owing to easy dendrite growth and serious side reactions. Herein, the preparation of heterogeneous interfacial film with highly dispersed and confined zinc salt in a 2D channel by coassembling polyamide 6, zinc trifluoromethanesulfonate, and layered double hydroxides, which significantly suppresses the dendrite formation, H evolution reaction as well as O corrosion is reported. Read More

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Nucleophilic Neutralization of Organophosphates: Lack of Selectivity or Plenty of Versatility?

Chem Rec 2021 Jun 11. Epub 2021 Jun 11.

Department of Chemistry, Universidade Federal do Paraná, CP 19081, CEP 81531-990, Curitiba, PR, Brazil.

Neutralization of organophosphates is an issue of public health and safety, involving agrochemicals and chemical warfare. A promising approach is the nucleophilic neutralization, scope of this review, which focuses on the molecular nucleophiles: hydroxide, imidazole derivatives, alpha nucleophiles, amines and other nucleophiles. A reactivity mapping is given correlating the pathways and reaction efficiency with structural dependence of the nucleophile (basicity) and the organophosphate (electrophilic centers, P=O/P=S shift, leaving and non-leaving group). Read More

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Phase Coexistence and Structural Dynamics of Redox Metal Catalysts Revealed by Operando TEM.

Adv Mater 2021 Jun 12:e2101772. Epub 2021 Jun 12.

Scientific Center for Optical and Electron Microscopy, ETH Zurich, Otto-Stern-Weg 3, Zurich, 8093, Switzerland.

Metal catalysts play an important role in industrial redox reactions. Although extensively studied, the state of these catalysts under operating conditions is largely unknown, and assignments of active sites remain speculative. Herein, an operando transmission electron microscopy study is presented, which interrelates the structural dynamics of redox metal catalysts to their activity. Read More

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Nanographene-Osmapentalyne Complexes as a Cathode Interlayer in Organic Solar Cells Enhance Efficiency over 18.

Adv Mater 2021 Jun 12:e2101279. Epub 2021 Jun 12.

Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, China.

Interface engineering is a critical method by which to efficiently enhance the photovoltaic performance of nonfullerene solar cells (NFSC). Herein, a series of metal-nanographene-containing large transition metal involving d -p conjugated systems by way of the addition reactions of osmapentalynes and p-diethynyl-hexabenzocoronenes is reported. Conjugated extensions are engineered to optimize the π-conjugation of these metal-nanographene molecules, which serve as alcohol-soluble cathode interlayer (CIL) materials. Read More

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Risk of Bleeding Associated with Antidepressant Drugs: The Competitive Impact of Antithrombotics in Quantitative Signal Detection.

Drugs Real World Outcomes 2021 Jun 11. Epub 2021 Jun 11.

Department of Psychiatry and Psychotherapy III, University of Ulm, Leimgrubenweg 12-14, 89075, Ulm, Germany.

Background: To date, disproportionality analysis has been unable to demonstrate the increased bleeding risk associated with antidepressant drugs, especially selective serotonin reuptake inhibitors.

Objective: We hypothesised that a potential signal for an increased bleeding risk may be mitigated by the effects of agents other than antidepressant drugs that are strongly associated with haemorrhages, especially antithrombotics. In addition, we investigated if the use of more specific search terms of the Medical Dictionary for Regulatory Activities facilitates the detection of signals. Read More

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Cabozantinib promotes erythroid differentiation in K562 erythroleukemia cells through global changes in gene expression and JNK activation.

Cancer Gene Ther 2021 Jun 11. Epub 2021 Jun 11.

Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University, Taipei, Taiwan.

Cabozantinib is a potent tyrosine kinase inhibitor with multiple targets including MET, VEGFR2, RET, KIT, and FLT3. Cabozantinib is widely used for the treatment of medullary thyroid cancer and renal cell carcinoma. We recently suggested cabozantinib as a potential therapeutic alternative for acute myeloid leukemia (AML) patients with FLT3-internal tandem duplication (FLT3-ITD). Read More

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Whole blood chromium concentration is very rarely elevated independently of whole blood cobalt.

Sci Rep 2021 Jun 11;11(1):12352. Epub 2021 Jun 11.

Coxa Hospital for Joint Replacement and Faculty of Medicine and Health Technologies, Tampere University, Niveltie 4, 33520, Tampere, Finland.

Due to the risk of adverse reactions to metal debris resulting from increased wear of the arthroplasty more than one million metal-on-metal (MoM) hip replacements worldwide are in active follow-up. Follow-up usually includes measurement of both whole blood cobalt (Co) and chromium (Cr) concentrations. Our experience is that Cr is seldom independently elevated. Read More

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Quasi-experimental evaluation of Kenya's pictorial health warnings versus Zambia's single text-only warning: findings from the International Tobacco Control (ITC) Project.

Tob Control 2021 Jun 11. Epub 2021 Jun 11.

Department of Psychology, University of Waterloo, Waterloo, Ontario, Canada.

Background: Population studies in mostly high-income countries have shown that pictorial health warnings (PHWs) are much more effective than text-only warnings. This is the first quasi-experimental evaluation of the introduction of PHWs in Africa, comparing the change from text-only to PHWs in Kenya to the unchanged text-only health warning in Zambia.

Methods: Data were from International Tobacco Control (ITC) Surveys in Kenya (n=1495), and Zambia (n=1628), cohort surveys of nationally representative samples of adult smokers in each country. Read More

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Unexpected overdose of oral cyclosporine in a kidney transplant patient: a case report.

Eur J Hosp Pharm 2021 Jun 11. Epub 2021 Jun 11.

Univ Rennes, CHU Rennes, Inserm, EHESP, IRSET (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France.

Cyclosporine is a widely used immunosuppressive agent to prevent rejection of solid organ transplant. Here, we describe the case of a 71-year-old man who received the prescribed dose of cyclosporine 10 times 6 days after a kidney transplantation because of a concentration miscalculation involving two galenic forms. The patient presented gastrointestinal and neurological disorders. Read More

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Combining generative artificial intelligence and on-chip synthesis for de novo drug design.

Sci Adv 2021 Jun 11;7(24). Epub 2021 Jun 11.

ETH Zurich, Department of Chemistry and Applied Biosciences, RETHINK, Zurich, Switzerland.

Automating the molecular design-make-test-analyze cycle accelerates hit and lead finding for drug discovery. Using deep learning for molecular design and a microfluidics platform for on-chip chemical synthesis, liver X receptor (LXR) agonists were generated from scratch. The computational pipeline was tuned to explore the chemical space of known LXRα agonists and generate novel molecular candidates. Read More

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Enzymatic production of 3'-sialyllactose in milk.

Enzyme Microb Technol 2021 Aug 14;148:109829. Epub 2021 May 14.

Section for Protein Chemistry and Enzyme Technology, Department of Biotechnology and Biomedicine, Building 221, Technical University of Denmark, Kgs. Lyngby, 2800, Denmark. Electronic address:

Human milk oligosaccharides (HMOs) are lactose-based glycan molecules present in human breast milk. HMOs are essentially not present in cow's milk and hence not naturally available in infant formulas. HMOs possess several health and developmentally beneficial properties, and the sialylated HMOs are thought to play a particularly important role for infant brain development. Read More

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C-type lectins and extracellular vesicles in virus-induced NETosis.

J Biomed Sci 2021 Jun 11;28(1):46. Epub 2021 Jun 11.

Genomics Research Center, Academia Sinica, 128, Academia Road, Sec. 2, Nankang District, Taipei, 115, Taiwan.

Dysregulated formation of neutrophil extracellular traps (NETs) is observed in acute viral infections. Moreover, NETs contribute to the pathogenesis of acute viral infections, including those caused by the dengue virus (DV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Furthermore, excessive NET formation (NETosis) is associated with disease severity in patients suffering from SARS-CoV-2-induced multiple organ injuries. Read More

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