93 results match your criteria: "Department of Chemistry University of California[Affiliation]"

Copper (Cu) is essential for respiration, neurotransmitter synthesis, oxidative stress response, and transcription regulation, with imbalances leading to neurological, cognitive, and muscular disorders. Here we show the role of a novel Cu-binding protein (Cu-BP) in mammalian transcriptional regulation, specifically on skeletal muscle differentiation using murine primary myoblasts. Utilizing synchrotron X-ray fluorescence-mass spectrometry, we identified murine cysteine-rich intestinal protein 2 (mCrip2) as a key Cu-BP abundant in both nuclear and cytosolic fractions.

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Plasmonic metal nanostructures can simultaneously scatter and absorb light, with resonance wavelength and strength depending on their morphology and composition. This work demonstrates that unique dichroic effects and high-contrast colour-switching can be achieved by leveraging the resonant scattering and absorption of light by plasmonic nanostructures and the specular reflection of the resulting transmitted light. Using core/shell nanostructures comprising a metal core and a dielectric shell, we show that their spray coating on reflective substrates produces dichroic films that can display colour switching at different viewing angles.

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Copper (Cu) is an essential trace element required for respiration, neurotransmitter synthesis, oxidative stress response, and transcriptional regulation. Imbalance in Cu homeostasis can lead to several pathological conditions, affecting neuronal, cognitive, and muscular development. Mechanistically, Cu and Cu-binding proteins (Cu-BPs) have an important but underappreciated role in transcription regulation in mammalian cells.

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Organic molecules that undergo supercooling can provide the basis for novel stimuli-responsive materials, but the number of such compounds is limited. Results in this paper show that the stable organic radical 2,2,6,6-tetramethyl-1-piperidine-1-oxyl (TEMPO) can form a stable supercooled liquid (SCL). Upon melting and cooling back to room temperature, the TEMPO SCL can persist for months, even after mild physical agitation.

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To realize an energy storage transition beyond Li-ion competitive technologies, earth-abundant elements, such as Mg, are needed. Carborane anions are particularly well-suited to realizing magnesium-ion batteries (MIBs), as their inert and weakly coordinating properties beget excellent electrolyte performance. However, utilizing these materials in actual electrochemical cells has been hampered by the reliance on the Mg salts of the commercially available [HCBH] anion, which is not soluble in more weakly binding solvents apart from the higher glymes.

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Premise: Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a chemical imaging method that can visualize spatial distributions of particular molecules. Plant tissue imaging has so far mostly used cryosectioning, which can be impractical for the preparation of large-area imaging samples, such as full flower petals. Imaging unsectioned plant tissue presents its own difficulties in extracting metabolites to the surface due to the waxy cuticle.

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BioMOF-Based Anti-Cancer Drug Delivery Systems.

Nanomaterials (Basel)

March 2023

Department of Chemistry, United Arab Emirates University, Al-Ain 15551, United Arab Emirates.

A variety of nanomaterials have been developed specifically for biomedical applications, such as drug delivery in cancer treatment. These materials involve both synthetic and natural nanoparticles and nanofibers of varying dimensions. The efficacy of a drug delivery system (DDS) depends on its biocompatibility, intrinsic high surface area, high interconnected porosity, and chemical functionality.

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PCIF1-mediated deposition of 5'-cap ,2'--dimethyladenosine in ACE2 and TMPRSS2 mRNA regulates susceptibility to SARS-CoV-2 infection.

Proc Natl Acad Sci U S A

January 2023

Division of Genetics, Program in Immunology, Bioinformatics and Systems Biology Program, Institute for Genomic Medicine, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be a major health problem worldwide. Due to the fast emergence of SARS-CoV-2 variants, understanding the molecular mechanisms of viral pathogenesis and developing novel inhibitors are essential and urgent. Here, we investigated the potential roles of ,2'--dimethyladenosine (mA), one of the most abundant modifications of eukaryotic messenger ribonucleic acid (mRNAs), in SARS-CoV-2 infection of human cells.

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Plant stress in a changing climate is predicted to increase plant volatile organic compound (VOC) emissions and thus can affect the formed secondary organic aerosol (SOA) concentrations, which in turn affect the radiative properties of clouds and aerosol. However, global aerosol-climate models do not usually consider plant stress induced VOCs in their emission schemes. In this study, we modified the monoterpene emission factors in biogenic emission model to simulate biotic stress caused by insect herbivory on needleleaf evergreen boreal and broadleaf deciduous boreal trees and studied the consequent effects on SOA formation, aerosol-cloud interactions as well as direct radiative effects of formed SOA.

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Introduction: There is an increased need for the development of novel blood-based biomarkers for early detection, prevention, or intervention in Alzheimer's disease (AD). This study sought to determine whether serum glycopeptide analysis holds potential for identifying novel diagnostics and prognostics of AD.

Methods: The study involved 195 participants, including 96 patients with an AD diagnosis and 99 controls with no cognitive deficit.

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Interstrand DNA cross-links (ICLs) are cytotoxic because they block the strand separation required for read-out and replication of the genetic information in duplex DNA. The unavoidable formation of ICLs in cellular DNA may contribute to aging, neurodegeneration, and cancer. Here, we describe the formation and properties of a structurally complex ICL derived from an apurinic/apyrimidinic (AP) site, which is one of the most common endogenous lesions in cellular DNA.

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The ultraviolet (UV) photodissociation dynamics of the jet-cooled cyclohexyl (-CH) radical is studied using the high- Rydberg atom time-of-flight (HRTOF) technique. The cyclohexyl radical is produced by the 193 nm photodissociation of chlorocyclohexane and bromocyclohexane and is examined in the photolysis wavelength region of 232-262 nm. The H-atom photofragment yield (PFY) spectrum contains a broad peak centered at 250 nm, which is in good agreement with the UV absorption spectrum of the cyclohexyl radical and assigned to the 3p Rydberg states.

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Prior work suggests drought exacerbates US air quality by increasing surface ozone concentrations. We analyze 2005-2015 tropospheric column concentrations of two trace gases that serve as proxies for surface ozone precursors retrieved from the OMI/Aura satellite: Nitrogen dioxide (ΩNO NO proxy) and formaldehyde (ΩHCHO; VOC proxy). We find 3.

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The abundances, relative distributions, and enantiomeric and isotopic compositions of amines, amino acids, and hydroxy acids in Miller Range (MIL) 090001 and MIL 090657 meteorites were determined. Chiral distributions and isotopic compositions confirmed that most of the compounds detected were indigenous to the meteorites and not the result of terrestrial contamination. Combined with data in the literature, suites of these compounds have now been analyzed in a set of six CR chondrites, spanning aqueous alteration types 2.

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Low molecular weight, uncharged compounds have been the subject of considerable study at advanced treatment plants employed for potable water reuse. However, previously identified compounds only account for a small fraction of the total dissolved organic carbon remaining after reverse osmosis treatment. Uncharged carbonyl compounds (e.

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The presence and accessibility of a sub-ice-surface saline ocean at Enceladus, together with geothermal activity and a rocky core, make it a compelling location to conduct further, in-depth, astrobiological investigations to probe for organic molecules indicative of extraterrestrial life. Cryovolcanic plumes in the south polar region of Enceladus enable the use of remote in situ sampling and analysis techniques. However, efficient plume sampling and the transportation of captured organic materials to an organic analyzer present unique challenges for an Enceladus mission.

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CD73, a cell-surface -linked glycoprotein that produces extracellular adenosine, is a novel target for cancer immunotherapy. Although anti-CD73 antibodies have entered clinical development, CD73 has both protumor and antitumor functions, depending on the target cell and tumor type. The aim of this study was to characterize CD73 regulation in human hepatocellular carcinoma (HCC).

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The dynamic response of the cell to osmotic changes is critical to its physiology and is widely exploited for cell manipulation. Here, using three-dimensional stochastic optical reconstruction microscopy (3D-STORM), a super-resolution technique, the hypotonic stress-induced ultrastructural changes of the cytoskeleton of a common fibroblast cell type are examined. Unexpectedly, these efforts lead to the discovery of a fast, yet reversible dissolution of the vimentin intermediate filament system that precedes ultrastructural changes of the supposedly more dynamic actin and tubulin cytoskeletal systems as well as changes in cell morphology.

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CAlX (X = B/Al/Ga/In/Tl) with 16 valence electrons: can planar tetracoordinate carbon be stable?

Phys Chem Chem Phys

November 2018

Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, P. R. China.

As a perpetual chemical curiosity, planar tetracoordinate carbon (ptC) that violates the traditional tetrahedral carbon (thC) has made enormous achievements. In particular, the 18-valence-electron (18ve) counting rule has been found to be very effective in predicting ptC structures, as in CX (X = Al/Ga/In/Tl). By contrast, the corresponding neutral CX with 16ve each takes the thC form like methane.

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Developing highly active, recyclable, and inexpensive photocatalysts for hydrogen evolution reaction (HER) under visible light is significant for the direct conversion of solar energy into chemical fuels for various green energy applications. For such applications, it is very challenging but vitally important for a photocatalyst to simultaneously enhance the visible-light absorption and suppress photogenerated electron-hole recombination, while also to maintain high stability and recyclability. Herein, a metal-organic framework (MOF)-templated strategy has been developed to prepare heterostructured nanocatalysts with superior photocatalytic HER activity.

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Tin-based chalcogenide semiconductors, though attractive materials for photovoltaics, have to date exhibited poor performance and stability for photoelectrochemical applications. Here, a novel strategy is reported to improve performance and stability of tin monosulfide (SnS) nanoplatelet thin films for H production in acidic media without any use of sacrificial reagent. P-type SnS nanoplatelet films are coated with the -CdS buffer layer and the TiO passivation layer to form type II heterojunction photocathodes.

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The environmental fates of nitenpyram (NPM), a widely used neonicotinoid insecticide, are not well-known. A thin solid film of NPM deposited on a germanium attenuated total reflectance (ATR) crystal was exposed to radiation from a low-pressure mercury lamp at 254 nm, or from broadband low pressure mercury photolysis lamps centered at 350 or 313 nm. The loss during photolysis was followed in time using FTIR.

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A 5,5- -luciferin was prepared to measure isotope effects on reactions of two intermediates in firefly bioluminescence: emission by oxyluciferin and elimination of a putative luciferyl adenylate hydroperoxide to dehydroluciferin. A negligible isotope effect on bioluminescence provides further support for the belief that the emitting species is the keto-phenolate of oxyluciferin and rules out its excited-state tautomerization, one potential contribution to a bioluminescence quantum yield less than unity. A small isotope effect on dehydroluciferin formation supports a single-electron-transfer mechanism for reaction of the luciferyl adenylate enolate with oxygen to form the hydroperoxide or dehydroluciferin.

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Computational Insights into Materials and Interfaces for Capacitive Energy Storage.

Adv Sci (Weinh)

July 2017

Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831 United States.

Supercapacitors such as electric double-layer capacitors (EDLCs) and pseudocapacitors are becoming increasingly important in the field of electrical energy storage. Theoretical study of energy storage in EDLCs focuses on solving for the electric double-layer structure in different electrode geometries and electrolyte components, which can be achieved by molecular simulations such as classical molecular dynamics (MD), classical density functional theory (classical DFT), and Monte-Carlo (MC) methods. In recent years, combining first-principles and classical simulations to investigate the carbon-based EDLCs has shed light on the importance of quantum capacitance in graphene-like 2D systems.

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Recent advances in graphene-based sensors have shown that heavily oxidized (GO) and reduced graphene oxide (rGO) are attractive materials for environmental sensing due to their unique chemical and physical properties. We describe here the fabrication of nanostructured GO assemblies with Ag nanoprisms for improved detection with surface enhanced Raman scattering (SERS). Specifically, 100-μm-sized, periodic-nanoprism-array domains were fabricated on top of the GO layers by GO-assisted lithography (GOAL).

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