47,841 results match your criteria undergoes ∼90-100

Development of an analytical method for the determination of pimavanserin and its impurities applying analytical quality by design principles as a risk-based strategy.

J Pharm Biomed Anal 2021 Apr 24;201:114091. Epub 2021 Apr 24.

Department of Analytical Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Trg Marka Marulića 19, 10000, Zagreb, Croatia. Electronic address:

Pimavanserin is an atypical antipsychotic indicated for the treatment of hallucinations and delusions associated with Parkinson's disease psychosis. As it is a relatively new drug on the market, limited number of pharmacokinetic information and analytical methods are available. This paper presents an ultra-high performance chromatography for the simultaneous determination of pimavanserin and its four process impurities. Read More

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Protein unfolded states populated at high and ambient pressure are similarly compact.

Biophys J 2021 May 4. Epub 2021 May 4.

Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy NY 12180. Electronic address:

The relationship between the dimensions of pressure unfolded states of proteins compared to those at ambient pressure is controversial; resolving this issue is related directly to the mechanisms of pressure denaturation. Moreover, a significant pressure dependence of the compactness of unfolded states would complicate the interpretation of folding parameters from pressure perturbation and make comparison to those obtained using alternative perturbation approaches difficult. Here we determined the compactness of the pressure-unfolded state of a small, cooperatively folding model protein, CTL9-I98A, as a function of temperature. Read More

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Conjugates of Human Serum Butyrylcholinesterase and Nerve Agents are Behaviorally Safe in Rhesus Macaques.

Chem Biol Interact 2021 May 4:109499. Epub 2021 May 4.

US Army War College, Carlisle, PA 17013, USA.

Exogenously administered human serum butyrylcholinesterase (Hu BChE) affords protection by binding to organophosphorus (OP) nerve agents and pesticides in circulation. The resulting Hu BChE-OP conjugate undergoes 'aging' and the conjugate circulates until cleared from the body. Thus, we evaluated the effects of Hu BChE-OP conjugates on the general health and operant behavior of macaques. Read More

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Enhancing Thermocatalytic Activities via Up-shift of the d-Band Center of Exsolved Co-Ni-Fe Ternary Alloy Nanoparticles for Dry Reforming of Methane.

Angew Chem Int Ed Engl 2021 May 7. Epub 2021 May 7.

Ulsan National Institute of Science and Technology (UNIST), Department of Energy Engineering, 701-8 Natural & Sci. Bldg., 50 UNIST-Gil, Eonyang-eup, Ulju-gun, 689-798, Ulsan, KOREA, REPUBLIC OF.

Dry reforming of methane (DRM) is a feasible solution to cope with the reduction of greenhouse gas under the Paris Convention's obligations, given that it adds value by converting trivial gases of CO2 and CH4 simultaneously into useful syngas. However, conventional Ni catalyst undergoes deactivation due to carbon coking and particle agglomeration. Here we demonstrate for the first time a highly efficient and durable DRM catalyst of exsolved Co-Ni-Fe ternary alloy nanoparticles on the layered perovskite PrBaMn1. Read More

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Modeling Amyloid Aggregation Kinetics: A Case Study with Sup35NM.

J Phys Chem B 2021 May 7. Epub 2021 May 7.

School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.

Understanding the aggregation mechanism of amyloid proteins, such as Sup35NM, is essential to understanding amyloid diseases. Significant recent work has focused on using the fluorescence of thioflavin T (ThT), which undergoes a red shift when bound to amyloid aggregates, to monitor amyloid fibril formation. In the present study, the progression of the total mass of aggregates during fibril formation is monitored for initial monomer concentrations in order to infer the relevant aggregation mechanisms. Read More

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Photodegradation of α-Pinene Secondary Organic Aerosol Dominated by Moderately Oxidized Molecules.

Environ Sci Technol 2021 May 7. Epub 2021 May 7.

Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland.

Atmospheric secondary organic aerosol (SOA) undergoes chemical and physical changes when exposed to UV radiation, affecting the atmospheric lifetime of the involved molecules. However, these photolytic processes remain poorly constrained. Here, we present a study aimed at characterizing, at a molecular level and in real time, the chemical composition of α-pinene SOA exposed to UV-A light at 50% relative humidity in an atmospheric simulation chamber. Read More

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Photocatalytic upgrading of lignin oil to diesel precursor and hydrogen.

Angew Chem Int Ed Engl 2021 May 7. Epub 2021 May 7.

Dalian University of Technology, Zhang Dayu school of chemistry, zhongshan road 457, dalian, China, 116024, Dalian, CHINA.

Producing renewable biofuels from biomass is a promising way to meet future energy demand. Here, we demonstrated a lignin to diesel route via dimerization of the lignin oil followed by hydrodeoxygenation. The lignin oil undergoes C-C bond dehydrogenative coupling over Au/CdS photocatalyst under visible light irradiation, co-generating diesel precursors and hydrogen. Read More

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Regulation of CTLA-4 recycling by LRBA and Rab11.

Immunology 2021 May 7. Epub 2021 May 7.

Institute of Immunity and Transplantation, University College London, London, United Kingdom.

CTLA-4 is an essential regulator of T cell immune responses whose intracellular trafficking is a hallmark of its expression. Defects in CTLA-4 trafficking due to LRBA deficiency cause profound autoimmunity in humans. CTLA-4 rapidly internalises via a clathrin-dependent pathway followed by poorly characterised recycling and degradation fates. Read More

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Memory binding and theta EEG during middle childhood.

Dev Psychobiol 2021 May 6. Epub 2021 May 6.

Department of Psychology, Virginia Tech, Blacksburg, Virginia, USA.

The ability to bind together the contextual details associated with an event undergoes dramatic improvement during childhood. However, few studies have examined the neural correlates of memory binding encoding and retrieval during middle childhood. We examined age-related encoding and retrieval differences using continuous electroencephalogram (EEG) measures in a sample of 6- and 8-year-olds. Read More

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A comparative test of the gamete dynamics theory for the evolution of anisogamy in Bryopsidales green algae.

R Soc Open Sci 2021 Mar 3;8(3):201611. Epub 2021 Mar 3.

Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool L69 7ZB, UK.

Gamete dynamics theory proposes that anisogamy arises by disruptive selection for gamete numbers versus gamete size and predicts that female/male gamete size (anisogamy ratio) increases with adult size and complexity. Evidence has been that in volvocine green algae, the anisogamy ratio correlates positively with haploid colony size. However, green algae show notable exceptions. Read More

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Comparison of Multimaterial Decomposition Fat Fraction with DECT and Proton Density Fat Fraction with IDEAL IQ MRI for Quantification of Liver Steatosis in a Population Exposed to Chemotherapy.

Dose Response 2021 Apr-Jun;19(2):1559325820984938. Epub 2021 Apr 20.

IRCCS SDN, Napoli, Italy.

Introduction: Oncologic patients who develop chemotherapy-associated liver injury (CALI) secondary to chemotherapy treatment tend to have worse outcomes. Biopsy remains the gold standard for the diagnosis of hepatic steatosis. The purpose of this article is to compare 2 alternatives: Proton-Density-Fat-Fraction (PDFF) MRI and MultiMaterial-Decomposition (MMD) DECT. Read More

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First-Principles Demonstration of Nonadiabatic Thouless Pumping of Electrons in a Molecular System.

J Phys Chem Lett 2021 May 6:4496-4503. Epub 2021 May 6.

Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.

We demonstrate nonadiabatic Thouless pumping of electrons in -polyacetylene in the framework of Floquet engineering using first-principles theory. We identify the regimes in which the quantized pump is operative with respect to the driving electric field for a time-dependent Hamiltonian. By employing the time-dependent maximally localized Wannier functions in real-time time-dependent density functional theory simulation, we connect the winding number, a topological invariant, to a molecular-level understanding of the quantized pumping. Read More

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A Self-Catalyzed Visible Light Driven Thiol Ligation.

J Am Chem Soc 2021 May 6. Epub 2021 May 6.

Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, Queensland 4000, Australia.

We introduce a highly efficient ligation system based on a visible light-induced rearrangement affording a thiophenol which rapidly undergoes thiol-Michael additions. Unlike conventional light-triggered thiol-ene/yne systems, which rely on the use of photocaged bases/nucleophiles, (organo)-photo catalysts, or radical photoinitiators, our system provides a light-induced reaction in the absence of any additives. The ligation is self-catalyzed the pyridine mediated deprotonation of the photochemically generated thiophenol. Read More

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Proton-controlled non-exponential photoluminescence in a pyridylamidine-substituted Re(I) complex.

Dalton Trans 2021 May 6. Epub 2021 May 6.

Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.

Chemical intuition and well-known design principles can typically be used to create ligand environments in transition metal complexes to deliberately tune reactivity for desired applications. However, intelligent ligand design does not always result in the expected outcomes. Herein we report the synthesis and characterization of a tricarbonyl rhenium (2,2'-bipyridine) 4-pyridylamidine, Re(4-Pam), complex with unexpected photophysical properties. Read More

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Protocol for assessing if behavioural functioning of infants born <29 weeks' gestation is improved by omega-3 long-chain polyunsaturated fatty acids: follow-up of a randomised controlled trial.

BMJ Open 2021 May 5;11(5):e044740. Epub 2021 May 5.

Discipline of Paediatrics, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia.

Introduction: During the last trimester of pregnancy, the fetal brain undergoes a rapid growth spurt and accumulates essential nutrients including docosahexaenoic acid (DHA). This takes place ex-utero for infants born <29 weeks' gestation, without the in-utero provisions of DHA. Infants born <29 weeks' are more likely to experience behavioural and emotional difficulties than their term-born counterparts. Read More

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Characterization of Stem Cells from Human Exfoliated Deciduous Anterior Teeth with Varying Levels of Root Resorption.

J Clin Pediatr Dent 2021 Apr;45(2):104-111

Background: Deciduous teeth undergo the physiologic process of resorption, during which the remnant pulp undergoes activation. However, the quality of stem cells obtained at various stages of root resorption has not been documented.

Objective: To isolate and characterize stem cells from deciduous teeth with varying levels of root resorption. Read More

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Bio-inspired Incrustation Interfacial Polymerization of Dopamine and Cross-linking with Gelatin toward Robust, Biodegradable Three-Dimensional Hydrogels.

Langmuir 2021 May 5. Epub 2021 May 5.

WPI-Advanced Institute for Materials Research (AIMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.

In nature, laccase enzymatically catalyzes the reaction of phenolic compounds with oxygen to produce hardened surfaces known as cuticles on insects and plants. Inspired by this natural process, the present work investigated a robust, biodegradable hydrogel synthesized from dopamine and gelatin. This gel is obtained by the oxidation of dopamine dissolved in water, after which the resulting quinone compound automatically undergoes self-polymerization. Read More

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Mechanistic studies of Cp*Ir(III)/Cp*Rh(III)-catalyzed branch-selective allylic C-H amidation: why is Cp*Ir(III) superior to Cp*Rh(III)?

Org Biomol Chem 2021 May;19(17):3850-3858

Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.

Density functional theory calculations have revealed the mechanism and origins of the reactivity and regioselectivity of the Cp*Ir(iii)/Cp*Rh(iii)-catalyzed allylic C-H amidation of alkenes and dioxazolones. Generally, the catalytic cycle consists of alkene coordination, C(sp3)-H activation, dioxazolone oxidative addition, reductive elimination and proto-demetallation to give the final amidation product. The C-H activation is found to be the rate-determining step, and it controls the reactivity of the reaction. Read More

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Step-wise and one-pot synthesis of highly substituted conjugated trienes from 2-oxobenzo[]chromenes/2-pyran-2-ones.

Org Biomol Chem 2021 May;19(17):3901-3910

Department of Chemistry, University of Delhi, North Campus, Delhi, 110007, India.

A mild and efficient route for the synthesis of conjugated trienes via nitroethane-mediated ring contraction of 2-oxobenzo[h]chromenes/2H-pyran-2-ones followed by decarboxylative rearrangement of the obtained spirobutenolides and butenolides is described. The (E)-isomer of trienes was obtained by step-wise and one-pot approaches from 2-oxobenzo[h]chromenes. Butenolides 4a-l as new substrates have been developed for the construction of trienes. Read More

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High temperature anionic Fe(III) spin crossover behavior in a mixed-valence Fe(II)/Fe(III) complex.

Dalton Trans 2021 May;50(17):5960-5967

Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.

Two ion-pair Fe(iii) complexes (PPh4)[FeIII(HATD)2]·2H2O (1, H3ATD = azotetrazolyl-2,7-dihydroxynaphthalene) and [FeII(phen)3][FeIII(HATD)2]2·3DMA·3.5H2O (2, phen = 1,10-phenanthroline, DMA = N,N-dimethylformamide) were synthesized by employing the tridentate ligand H3ATD. Crystal structure analyses reveal that complexes 1 and 2 consist of FeIII ions in an octahedral environment where a FeIII ion is coordinated by two HATD2- ligands forming the [FeIII(HATD)2]- core. Read More

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Viral Evolution Identifies a Critical Residue in the Alphaherpesvirus Fusion Glycoprotein B Ectodomain That Controls gH/gL-Independent Entry.

mBio 2021 05 4;12(3). Epub 2021 May 4.

Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany

Herpesvirus entry and spread requires fusion of viral and host cell membranes, which is mediated by the conserved surface glycoprotein B (gB). Upon activation, gB undergoes a major conformational change and transits from a metastable prefusion to a stable postfusion conformation. Although gB is a structural homolog of low-pH-triggered class III fusogens, its fusion activity depends strictly on the presence of the conserved regulatory gH/gL complex and nonconserved receptor binding proteins, which ensure that fusion occurs at the right time and space. Read More

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Operando Monitoring the Insulator-Metal Transition of LiCoO.

ACS Appl Mater Interfaces 2021 May 4. Epub 2021 May 4.

Department of Chemistry, Ångström Laboratory, Uppsala University, Box 538, SE-751 21 Uppsala, Sweden.

LiCoO (LCO) is one of the most-widely used cathode active materials for Li-ion batteries. Even though the material undergoes an electronic two-phase transition upon Li-ion cell charging, LCO exhibits competitive performance in terms of rate capability. Herein the insulator-metal transition of LCO is investigated by Raman spectroscopy complemented with DFT calculations and a developed sampling volume model. Read More

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Recent Advances in Effector-Triggered Immunity in Plants: New Pieces in the Puzzle Create a Different Paradigm.

Int J Mol Sci 2021 Apr 29;22(9). Epub 2021 Apr 29.

Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 52828, Korea.

Plants rely on multiple immune systems to protect themselves from pathogens. When pattern-triggered immunity (PTI)-the first layer of the immune response-is no longer effective as a result of pathogenic effectors, effector-triggered immunity (ETI) often provides resistance. In ETI, host plants directly or indirectly perceive pathogen effectors via resistance proteins and launch a more robust and rapid defense response. Read More

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In Search of a Role for Extracellular Purine Enzymes in Bone Function.

Biomolecules 2021 Apr 30;11(5). Epub 2021 Apr 30.

Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Via dei Vestini 29, 66100 Chieti, Italy.

Bone is one of the major tissues that undergoes continuous remodeling throughout life, thus ensuring both organic body growth during development and protection of internal organs as well as repair of trauma during adulthood. Many endogenous substances contribute to bone homeostasis, including purines. Their role has increasingly emerged in recent decades as compounds which, by interacting with specific receptors, can help determine adequate responses of bone cells to physiological or pathological stimuli. Read More

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Phosphorylation-dependent subfunctionalization of the calcium-dependent protein kinase CPK28.

Proc Natl Acad Sci U S A 2021 May;118(19)

Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada;

Calcium (Ca)-dependent protein kinases (CDPKs or CPKs) are a unique family of Ca sensor/kinase-effector proteins with diverse functions in plants. In , CPK28 contributes to immune homeostasis by promoting degradation of the key immune signaling receptor-like cytoplasmic kinase BOTRYTIS-INDUCED KINASE 1 (BIK1) and additionally functions in vegetative-to-reproductive stage transition. How CPK28 controls these seemingly disparate pathways is unknown. Read More

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The Ins and Outs of Plasmodium Rhoptries, Focusing on the Cytosolic Side.

Trends Parasitol 2021 Apr 30. Epub 2021 Apr 30.

Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide 5005, Australia; Burnet Institute, 85 Commercial Road, Melbourne 3004, Victoria, Australia. Electronic address:

Parasites of the genus Plasmodium cause human and animal malaria, leading to significant health and economic impacts. A key aspect of the complex life cycle of Plasmodium parasites is the invasion of the parasite into its host cell, which is mediated by secretory organelles. The largest of these organelles, the rhoptry, undergoes rapid and profound physiological changes when it secretes its contents during merozoite and sporozoite invasion of the host erythrocyte and hepatocyte, respectively. Read More

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Dairy cow health and management in the transition period: The need to understand the human dimension.

Res Vet Sci 2021 Apr 27;137:94-101. Epub 2021 Apr 27.

Department of Veterinary Health and Animal Sciences, Harper Adams University, Newport, Shropshire TF10 8NB, United Kingdom.

During the transition from the dry period to lactation the dairy cow undergoes a period of physiological, metabolic and immunological change, and is at greater risk of developing disease, to the detriment of health, welfare and production. Many studies have been undertaken to determine appropriate management strategies to improve health and welfare during the transition period, however the incidence of disease, particularly metabolic disease, in this period remains high. To date, a lack of research attention has been paid to the social factors which may affect the management of transition dairy cows. Read More

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4D Printing of Hygroscopic Liquid Crystal Elastomer Actuators.

Small 2021 May 2:e2100910. Epub 2021 May 2.

Department of Polymer Science and Engineering, Pusan National University, Busan, 46241, Republic of Korea.

Liquid crystal elastomers (LCEs) are broadly recognized as programmable actuating materials that are responsive to external stimuli, typically heat or light. Yet, soft LCEs that respond to changes in environmental humidity are not reported, except a few examples based on rigid liquid crystal networks with limited processing. Herein, a new class of highly deformable hygroscopic LCE actuators that can be prepared by versatile processing methods, including surface alignment as well as 3D printing is presented. Read More

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USP44 Stabilizes DDB2 to Facilitate Nucleotide Excision Repair and Prevent Tumors.

Front Cell Dev Biol 2021 16;9:663411. Epub 2021 Apr 16.

Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN, United States.

Nucleotide excision repair (NER) is a pathway involved in the repair of a variety of potentially mutagenic lesions that distort the DNA double helix. The ubiquitin E3-ligase complex UV-DDB is required for the recognition and repair of UV-induced cyclobutane pyrimidine dimers (CPDs) lesions through NER. DDB2 directly binds CPDs and subsequently undergoes ubiquitination and proteasomal degradation. Read More

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Fibrillarin-GFP Facilitates the Identification of Meiotic Competent Oocytes.

Ting Wang Jie Na

Front Cell Dev Biol 2021 15;9:648331. Epub 2021 Apr 15.

Center for Stem Cell Biology and Regenerative Medicine, School of Medicine, Tsinghua University, Beijing, China.

The nucleolus undergoes significant functional changes and plays important roles during mammalian oocyte meiotic maturation. Fibrillarin (FBL) is the component of nucleolar small nuclear ribonucleoprotein (snRNP) particle and localizes to the dense fibrillar component (DFC) of the nucleolus. We found that FBL-GFP displays an uneven and cloudy localization in the nucleolus of non-surrounded nucleolus (NSN) oocytes, while it distributes evenly and to a few bright dots in the surrounded nucleolus (SN) oocytes. Read More

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