Read by QxMD icon Read


Isabel P G Fernandes, Ana Maria Oliveira-Brett
Calmodulin (CaM) is an essential protein present in all eukaryote cells, ranging from vertebrates to unicellular organisms. CaM is the most important Ca(2+) signalling protein, composed of two domains, N- and C-terminal domains, linked by a flexible central α-helix, and is responsible for the regulation of numerous calcium-mediated signalling pathways. Four calcium ions bind to CaM, changing its conformation and determining how it recognizes and regulates its cellular targets. The oxidation mechanism of native and denatured CaM, at a glassy carbon electrode, was investigated using differential pulse voltammetry and electrochemical impedance spectroscopy...
October 7, 2016: Bioelectrochemistry
Tian Hua, Kiran Vemuri, Mengchen Pu, Lu Qu, Gye Won Han, Yiran Wu, Suwen Zhao, Wenqing Shui, Shanshan Li, Anisha Korde, Robert B Laprairie, Edward L Stahl, Jo-Hao Ho, Nikolai Zvonok, Han Zhou, Irina Kufareva, Beili Wu, Qiang Zhao, Michael A Hanson, Laura M Bohn, Alexandros Makriyannis, Raymond C Stevens, Zhi-Jie Liu
Cannabinoid receptor 1 (CB1) is the principal target of Δ(9)-tetrahydrocannabinol (THC), a psychoactive chemical from Cannabis sativa with a wide range of therapeutic applications and a long history of recreational use. CB1 is activated by endocannabinoids and is a promising therapeutic target for pain management, inflammation, obesity, and substance abuse disorders. Here, we present the 2.8 Å crystal structure of human CB1 in complex with AM6538, a stabilizing antagonist, synthesized and characterized for this structural study...
October 20, 2016: Cell
Shlomo Sasson
Activated peroxisome proliferator-activated receptor-δ (PPARδ) induces the expression of genes encoding enzymes that metabolize fatty acids and carbohydrate. Attempts to identify cellular activators of PPARδ produced large lists of various fatty acids and their metabolic derivatives; however, there is no consensus on specific and selective binding interactions of natural ligands with PPARδ. Most models on binding interactions within the ligand binding domain (LBD) of PPARδ have been derived from analyses of PPARδ-LBD crystals formed with synthetic low molecular weight ligands...
October 18, 2016: Biochimie
Durga Mahor, Anu Priyanka, Gandham S Prasad, Krishan Gopal Thakur
Consumption of foods and beverages with high purine content increases the risk of hyperuricemia, which causes gout and can lead to cardiovascular, renal, and other metabolic disorders. As patients often find dietary restrictions challenging, enzymatically lowering purine content in popular foods and beverages offers a safe and attractive strategy to control hyperuricemia. Here, we report structurally and functionally characterized purine nucleoside phosphorylase (PNP) from Kluyveromyces lactis (KlacPNP), a key enzyme involved in the purine degradation pathway...
2016: PloS One
Joseph K Maddry, Alejandra G Mora, Shelia Savell, Lauren K Reeves, Crystal A Perez, Vikhyat S Bebarta
BACKGROUND: Medical evacuation (MEDEVAC) is the movement and en route care of injured and medically compromised patients by medical care providers via helicopter. Military MEDEVAC platforms provide lifesaving interventions that improve survival in combat. There is limited evidence to support decision making related to en route care and allocation of resources. The association between provider type and en route care is not well understood. Our objective was to describe MEDEVAC providers and identify associations between provider type, procedures performed, and outcomes...
November 2016: Journal of Trauma and Acute Care Surgery
B Hehlen, M Al-Sabbagh, A Al-Zein, J Hlinka
The fluctuations of electric polarization in a disordered ferroelectric substance, relaxor crystal PbMg_{1/3}Nb_{2/3}O_{3} (PMN), were studied using a nonlinear inelastic light-scattering technique, hyper-Raman scattering, within a 5-100  cm^{-1} spectral interval and in a broad temperature range from 20 to 900 K. The split ferroelectric mode reveals a local anisotropy of up to about 400 K. Spectral anomalies observed at higher temperatures are explained as due to avoided crossing of the single primary polar soft mode with a temperature-independent, nonpolar spectral feature near 45  cm^{-1}, known from Raman scattering...
October 7, 2016: Physical Review Letters
Nan Wang, Kirk H Bevan, Nikolas Provatas
We propose an atomistic model of electromigration (EM) in metals based on a recently developed phase-field-crystal (PFC) technique. By coupling the PFC model's atomic density field with an applied electric field through the EM effective charge parameter, EM is successfully captured on diffusive time scales. Our framework reproduces the well-established EM phenomena known as Black's equation and the Blech effect, and also naturally captures commonly observed phenomena such as void nucleation and migration in bulk crystals...
October 7, 2016: Physical Review Letters
R Stannarius, K Harth
Disclinations in liquid crystals bear striking analogies to defect structures in a wide variety of physical systems, and their straightforward optical observability makes them excellent models to study fundamental properties of defect interactions. We employ freely suspended smectic-C films, which behave as quasi-two-dimensional polar nematics. A procedure to capture high-strength disclinations in localized spots is introduced. These disclinations are released in a controlled way, and the motion of the mutually repelling topological charges with strength +1 is studied quantitatively...
October 7, 2016: Physical Review Letters
Shuai Gao, Man Pan, Yong Zheng, Yichao Huang, Qingyun Zheng, Demeng Sun, Lining Lu, Xiaodan Tan, Xianglong Tan, Huan Lan, Jiaxing Wang, Tian Wang, Jiawei Wang, Lei Liu
Racemic or quasi-racemic crystallography recently emerges as a useful technology for solution of the crystal structures of biomacromolecules. It remains unclear to what extent the biomacromolecules of opposite handedness can differ from each other in racemic or quasi-racemic crystallography. Here we report a finding that monomeric d-ubiquitin (Ub) has propensity to cocrystallize with different dimers, trimers, and even a tetramer of l-Ub. In these cocrystals the unconnected monomeric d-Ubs can self-assemble to form pseudomirror images of different oligomers of l-Ub...
October 21, 2016: Journal of the American Chemical Society
Bo Zhang, Jun Li, Cheng-Feng Du, Mei-Ling Feng, Xiao-Ying Huang
An open-framework chalcogenidostannate, namely, [CH3NH3]2Ag4Sn(IV)2Sn(II)S8 (1), has been solvothermally synthesized and structurally characterized, which represents the first organically templated three-dimensional (3D) Ag-Sn-S compound containing the mixed valence of Sn(IV)/Sn(II) and displays visible-light-driven photocatalytic activity for degradation of crystal violet (CV).
October 21, 2016: Inorganic Chemistry
Yin-Shan Meng, Shang-Da Jiang, Bing-Wu Wang, Song Gao
Single-molecule magnets (SMMs) can retain their magnetization status preferentially after removal of the magnetic field below a certain temperature. The unique property, magnetic bistable status, enables the molecule-scale SMM to become the next-generation high-density information storage medium. SMMs' new applications are also involved in high-speed quantum computation and molecular spintronics. The development of coordination chemistry, especially in transition metal (3d) and lanthanide (4f) complexes, diversifies SMMs by introducing new ones...
October 21, 2016: Accounts of Chemical Research
Elena Sugrue, Paul D Carr, Colin Scott, Colin J Jackson
The desolvation of ionizable residues in the active sites of enzymes and the subsequent effects on catalysis and thermostability have been studied in model systems, yet little is known regarding how enzymes can naturally evolve active sites with highly reactive and desolvated charges. Variants of triazine hydrolase (TrzN) with significant differences in their active sites have been isolated from different bacterial strains: TrzN from Nocardioides sp. strain MTD22 contains a catalytic glutamate residue (Glu241) that is surrounded by hydrophobic and aromatic second-shell residues (Pro214, Tyr215), whereas TrzN from Nocardioides sp...
October 21, 2016: Biochemistry
Stephanie Heinzlmeir, Denis Kudlinzki, Sridhar Sreeramulu, Susan Klaeger, Santosh Lakshmi Gande, Verena Linhard, Mathias Wilhelm, Huichao Qiao, Dominic Helm, Benjamin Ruprecht, Krishna Saxena, Guillaume Médard, Harald Schwalbe, Bernhard Kuster
The receptor tyrosine kinase EPHA2 (Ephrin type-A receptor 2) plays important roles in oncogenesis, metastasis and treatment resistance yet therapeutic targeting, drug discovery or investigation of EPHA2 biology is hampered by the lack of appropriate inhibitors and structural information. Here, we used chemical proteomics to survey 235 clinical kinase inhibitors for their kinase selectivity and identified 24 drugs with sub-micromolar affinities for EPHA2. NMR-based conformational dynamics together with nine new co-crystal structures delineated drug-EPHA2 interactions in full detail...
October 21, 2016: ACS Chemical Biology
Sk Imran Ali, Reinhard K Kremer, Mats Johnsson
The new quaternary layered oxide CoMo2Sb2O10 was synthesized by hydrothermal synthesis techniques, and its structure was determined from single-crystal X-ray diffraction data. CoMo2Sb2O10 crystallizes in the monoclinic space group C2/c with one Sb(3+), Mo(6+), and Co(2+) atom site per unit cell, respectively. The crystal structure contains building units consisting of [Co2O8]n, [Mo2O8]n, and [SbO2]n chains. These are connected through corner sharing to form charge-neutral [CoMo2Sb2O10]n layers. Thermal decomposition of CoMo2Sb2O10 starts at 550 °C...
October 21, 2016: Inorganic Chemistry
Alexandre Darmon, Michael Benzaquen, Simon Čopar, Olivier Dauchot, Teresa Lopez-Leon
We investigate experimentally and numerically the defect configurations emerging when a cholesteric liquid crystal is confined to a spherical shell. We uncover a rich scenario of defect configurations, some of them non-existent in nematic shells, where new types of defects are stabilized by the helical ordering of the liquid crystal. In contrast to nematic shells, here defects are not simple singular points or lines, but have a large structured core. Specifically, we observe five different types of cholesteric shells...
October 21, 2016: Soft Matter
Gianluigi Franci, Federica Sarno, Angela Nebbioso, Lucia Altucci
Epigenetic modifications are functionally involved in gene expression regulation. In particular, histone posttranslational modifications play a crucial role in functional chromatin organization. Several drugs able to inhibit or stimulate some families of proteins involved in epigenetic histone regulation have been found, a number of which are FDA-approved for the treatment of cutaneous T-cell lymphoma or are in phase I/II/III clinical trials for solid tumors. Although some protein families, such as histone deacetylases and their inhibitors, are well characterized, our understanding of histone lysine demethylases is still incomplete...
October 21, 2016: Epigenetics: Official Journal of the DNA Methylation Society
Yu-Zhi Sun, Bo Huang, Wei-Jian Xu, Dong-Dong Zhou, Shao-Li Chen, Shi-Yong Zhang, Zi-Yi Du, Yong-Rong Xie, Chun-Ting He, Wei-Xiong Zhang, Xiao-Ming Chen
Plastic crystals functioning with rotatable components offer new opportunities in areas such as modern optoelectronic materials. Here, by taking advantage of controllable rotation of the polar component within the ion-pair plastic-crystal system, we present two such crystals, namely, (Et4N)(CrO3X) (X = Cl or Br), which are unusual examples exhibiting two-staged thermosensitive dielectric responses above room temperature. The frequency-dependent response in the first stage is due to the structural phase transitions, whereas that in the second stage is induced by dynamic rotation of the polar halochromate anions in their NaCl-type plastic-crystal phases...
October 21, 2016: Inorganic Chemistry
Ke Yuan, Sang Soo Lee, Vincent De Andrade, Neil C Sturchio, Paul Fenter
The mobility of toxic elements, such as lead (Pb) can be attenuated by adsorption, incorporation, and precipitation on carbonate minerals in subsurface environments. Here, we report a study of the bulk transformation of single-crystal calcite (CaCO3) into polycrystalline cerussite (PbCO3) through reaction with acidic Pb-bearing solutions. This reaction began with the growth of a cerussite shell on top of calcite surfaces followed by the replacement of the remaining calcite core. The external shape of the original calcite was preserved by a balance between calcite dissolution and cerussite growth controlled by adjusting the Pb(2)(+) concentration and pH...
October 21, 2016: Environmental Science & Technology
Matthew R Noerpel, Sang Soo Lee, John J Lenhart
Predicting the environmental fate of lead relies on a detailed understanding of its coordination to mineral surfaces, which in turn reflects the innate reactivity of the mineral surface. In this research, we investigated fundamental dependencies in lead adsorption to hematite by coupling extended X-ray absorption fine structure (EXAFS) spectroscopy on hematite particles (10 and 50 nm) with resonant anomalous X-ray reflectivity (RAXR) to single crystals expressing the (001), (012), or (110) crystallographic face...
October 21, 2016: Environmental Science & Technology
Shan Wang, Changmin Hou, Long Yuan, Mingyang Qu, Bo Zou, Dayong Lu
Perovskite structured rare-earth chromites are one of the most promising families of functional materials in solid oxide fuel cells, multiferroic materials, and sensors. Here, we report a mild hydrothermal method to synthesize DyCrO3 and HoCrO3 monodispersed single crystals. The synthesis conditions, crystal structure, Raman spectra and temperature- and field-dependent magnetic properties were studied. The two samples are indexed to the Pbnm space group. The shapes of the crystals are plates with a narrow particle size distribution in the range of 4-5 μm...
October 21, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"