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CT theory and use

Ling Xue, Nick Holford, Xiao-Liang Ding, Zhen-Ya Shen, Chen-Rong Huang, Hua Zhang, Jing-Jing Zhang, Zhe-Ning Guo, Cheng Xie, Ling Zhou, Zhi-Yao Chen, Lin-Sheng Liu, Li-Yan Miao
AIMS: The aims of this study are to apply a theory based mechanistic model to describe the pharmacokinetics (PK) and pharmacodynamics (PD) of S- and R-warfarin. METHODS: Clinical data were obtained from 264 patients. Total concentrations for S- and R-warfarin were measured by ultra-high performance liquid tandem mass spectrometry. Genotypes were measured using pyrosequencing. A sequential population pharmacokinetic parameter with data method was used to describe the international normalized ratio (INR) time course...
October 20, 2016: British Journal of Clinical Pharmacology
Silvio Danese, Stefanos Bonovas, Laurent Peyrin-Biroulet
Biologic agents have revolutionized the care management of many life-threatening and debilitating diseases. As patents for older biologic therapies have begun to expire, the market has opened to copy versions of the originators - commonly referred to as biosimilars, follow-on biologic agents or subsequent-entry biologic agents - which are expected to gain a portion of the market, reduce health-care spending and increase treatment access worldwide. Importantly for patients with IBD, CT-P13 was the first biosimilar to infliximab that obtained regulatory approval by the European Medicines Agency in September 2013 and by the FDA in April 2016...
October 12, 2016: Nature Reviews. Gastroenterology & Hepatology
Yuezhi Mao, Omar Demerdash, Martin Head-Gordon, Teresa Head-Gordon
AMOEBA is a molecular mechanics force field that addresses some of the shortcomings of a fixed partial charge model, by including permanent atomic point multipoles through quadrupoles, as well as many-body polarization through the use of point inducible dipoles. In this work we investigate how well AMOEBA formulates its non-bonded interactions, and how it implicitly incorporates quantum mechanical effects such as charge penetration (CP) and charge transfer (CT), for water-water and water-ion interactions. We find that AMOEBA's total interaction energies as a function of distance and over angular scans for the water dimer and for a range of water-monovalent cations agree well with an advanced density functional theory (DFT) model, whereas the water-halides and water- divalent cations show significant disagreement with the DFT result, especially in the compressed region when the two fragments overlap...
October 6, 2016: Journal of Chemical Theory and Computation
Luzhen Deng, Peng Feng, Mianyi Chen, Peng He, Biao Wei
Compressive Sensing (CS) theory has great potential for reconstructing Computed Tomography (CT) images from sparse-views projection data and Total Variation- (TV-) based CT reconstruction method is very popular. However, it does not directly incorporate prior images into the reconstruction. To improve the quality of reconstructed images, this paper proposed an improved TV minimization method using prior images and Split-Bregman method in CT reconstruction, which uses prior images to obtain valuable previous information and promote the subsequent imaging process...
2016: BioMed Research International
Amlan K Pal, David B Cordes, Alexandra M Z Slawin, Cristina Momblona, Enrique Ortı, Ifor D W Samuel, Henk J Bolink, Eli Zysman-Colman
The structure-property relationship study of a series of cationic Ir(III) complexes in the form of [Ir(C^N)2(dtBubpy)]PF6 [where dtBubpy = 4,4'-di-tert-butyl-2,2'-bipyridine and C^N = cyclometallating ligand bearing an electron-withdrawing group (EWG) at C4 of the phenyl substituent, i.e., -CF3 (1), -OCF3 (2), -SCF3 (3), -SO2CF3 (4)] has been investigated. The physical and optoelectronic properties of the four complexes were comprehensively characterized, including by X-ray diffraction analysis. All the complexes exhibit quasireversible dtBubpy-based reductions from -1...
October 17, 2016: Inorganic Chemistry
Celal Tuğrul Zeyrek, Bahadir Boyacioğlu, Mustafa Yıldız, Hüseyin Ünver, Devrim Yolal, Neslihan Demir, Ayhan Elmali, Solomon Tadesse, Kadir Aslan
An amino acid based and bidentate Schiff base, (E)-methyl 2-((2-oxonaphthalen-1(2H)-ylidene)methylamino)acetate (ligand), was synthesized from the reaction of glycine-methyl ester hydrochloride with 2-hydroxy-1-naphthaldehyde. Characterization of the ligand was carried out using theoretical quantum-mechanical calculations and experimental spectroscopic methods. The molecular structure of the compound was confirmed using X-ray single-crystal data, NMR, FTIR and UV-Visible spectroscopy, which were in good agreement with the structure predicted by the theoretical calculations using density functional theory (DFT)...
November 1, 2016: Bioorganic & Medicinal Chemistry
Stephanie Y Pun, Andreas Hingsammer, Michael B Millis, Young-Jo Kim
BACKGROUND: Surgical treatment for pincer femoroacetabular impingement (FAI) of the hip remains controversial, between trimming the prominent acetabular rim and reverse periacetabular osteotomy (PAO) that reorients the acetabulum. However, rim trimming may decrease articular surface size to a critical threshold where increased joint contact forces lead to joint degeneration. Therefore, knowledge of how much acetabular articular cartilage is available for resection is important when evaluating between the two surgical options...
September 8, 2016: Clinical Orthopaedics and related Research
François Therrien, Annie Quinney, Kohei Tanaka, Darla K Zelenitsky
Mandibular force profiles apply the principles of beam theory to identify mandibular biomechanical properties that reflect the bite force and feeding strategies of extant and extinct predators. While this method uses external dimensions of the mandibular corpus to determine its biomechanical properties, more accurate results could potentially be obtained by quantifying its internal cortical bone distribution. To test this possibility, mandibular force profiles were calculated using both external mandibular dimensions ('solid mandible model') and quantification of internal bone distribution of the mandibular corpus obtained from CT scans ('hollow mandible model') for five carnivorans (Canis lupus, Crocuta crocuta, Panthera leo, Neofelis nebulosa, and the extinct Canis dirus)...
September 15, 2016: Journal of Experimental Biology
Hui Zhang, Christian Wernz, Danny R Hughes
Payment innovations that better align incentives in health care are a promising approach to reduce health care costs and improve quality of care. Designing effective payment systems, however, is challenging due to the complexity of the health care system with its many stakeholders and their often conflicting objectives. There is a lack of mathematical models that can comprehensively capture and efficiently analyze the complex, multi-level interactions and thereby predict the effect of new payment systems on stakeholder decisions and system-wide outcomes...
September 1, 2016: Health Care Management Science
R Oftadeh, Z Karimi, J Villa-Camacho, E Tanck, N Verdonschot, R Goebel, B D Snyder, H N Hashemi, A Vaziri, A Nazarian
In this paper, a CT based structural rigidity analysis (CTRA) method that incorporates bone intrinsic local curvature is introduced to assess the compressive failure load of human femur with simulated lytic defects. The proposed CTRA is based on a three dimensional curved beam theory to obtain critical stresses within the human femur model. To test the proposed method, ten human cadaveric femurs with and without simulated defects were mechanically tested under axial compression to failure. Quantitative computed tomography images were acquired from the samples, and CTRA and finite element analysis were performed to obtain the failure load as well as rigidities in both straight and curved cross sections...
2016: Scientific Reports
Pananghat Achutha Kumar, Ramakrishnan Jothi, Dharmalingam Mathivanan
BACKGROUND: A contemporary anatomy curriculum that aims to be clinically relevant requires medical students to be introduced to radiological anatomy in the preclinical years. Ideally, the curriculum should also support self-directed learning, a habit best instilled early. Based on these educational requirements, we designed an interesting and clinically-meaningful program of self-learning modules in radiological anatomy to augment students' learning of gross anatomy. The program is guided by current theories of learning, which emphasize an individualized learning pace for students...
May 2016: Education for Health: Change in Training & Practice
Xiao Liu, Kan Ding, Anurag Panda, Stephen R Forrest
We study the charge transfer (CT) states in small-molecule blend heterojunctions comprising the nonpolar donor, tetraphenyldibenzoperiflanthene (DBP), and the acceptor, C70, using electroluminescence and steady-state and time-resolved photoluminescence spectroscopy along with density functional theory calculations. We find that the CT exciton energy blue shifts as the C70 concentration in the blend is either decreased or increased away from 50 vol %. At 20 K, the increase in CT state lifetime is correlated with the increasing diameter of C70 nanocrystallites in the blends...
August 23, 2016: ACS Nano
Lara Martinez-Fernandez, Yuyuan Zhang, Kimberly de La Harpe, Ashley A Beckstead, Bern Kohler, Roberto Improta
The IR spectrum of a charge transfer (CT) excited electronic state in DNA has been computed for the first time, enabling assignment of the long-lived component of the transient IR spectrum of a d(AT)9 single strand to an A → T CT state. Experimentally, the CT state lifetime is much shorter than in the double strand, and our calculations explain this result using Marcus Theory.
August 21, 2016: Physical Chemistry Chemical Physics: PCCP
Khrystyna Herasymchuk, Linus Chiang, Cassandra E Hayes, Matthew L Brown, Jeffrey S Ovens, Brian O Patrick, Daniel B Leznoff, Tim Storr
Pentagonal bipyramidal uranyl (UO2(2+)) complexes of salen ligands, N,N'-bis(3-tert-butyl-(5R)-salicylidene)-1,2-phenylenediamine, in which R = (t)Bu (1a), OMe (1b), and NMe2 (1c), were prepared and the electronic structure of the one-electron oxidized species [1a-c]+ were investigated in solution. The solid-state structures of 1a and 1b were solved by X-ray crystallography, and in the case of 1b an asymmetric UO2(2+) unit was found due to an intermolecular hydrogen bonding interaction. Electrochemical investigation of 1a-c by cyclic voltammetry showed that each complex exhibited at least one quasi-reversible redox process assigned to the oxidation of the phenolate moieties to phenoxyl radicals...
August 2, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Mridula, Mala Nath
Diorganotin(IV) complexes of the general formulae {[R2Sn(L)]2O}(R=Me (1), n-Bu (2), and n-Oct (3); L=anion of mandelic acid) and {[R2Sn(L)]2Cl2}(R=Ph (4)) have been synthesized by conventional thermal method (1a-3a), except 4a and by microwave-assisted reactions (1b-4b). The elemental analysis, IR, NMR ((1)H, (13)C and (119)Sn) and ESI-MS/DART-mass spectral studies revealed that dimeric 1:1 complexes with SnOSn bridges (1-3) are formed possessing distorted trigonal bipyramidal geometry around the Sn atoms, except 4b which exhibits octahedral geometry with SnClSn bridges...
September 2016: Journal of Photochemistry and Photobiology. B, Biology
Suehiro Iwata, Dai Akase, Misako Aida, Sotiris S Xantheas
The influence of the nearest neighbor and next-nearest neighbor water molecules on the strength of the hydrogen (H) bonds was examined for the polyhedral clusters of cubic (H2O)8, dodecahedral (H2O)20 and tetrakaidecahedral (H2O)24 cages. The relative stability and the characteristics of the H bond networks are also studied. The charge-transfer (CT) and dispersion interaction terms of every pair of H bonds are evaluated using perturbation theory based on the locally-projected molecular orbitals (LPMO PT). Every water molecule and every H-bonded pair in these polyhedral clusters are classified by the types of the neighbor molecules and H bonds...
July 20, 2016: Physical Chemistry Chemical Physics: PCCP
J Tobias Kühl, Jens D Hove, Thomas S Kristensen, Jakob B Norsk, Thomas Engstrøm, Lars Køber, Henning Kelbæk, Klaus F Kofoed
OBJECTIVES: To test if cardiac computed tomography angiography (CCTA) can be used in the triage of patients at high risk of coronary artery disease. DESIGN: The diagnostic value of 64-detector CCTA was evaluated in 400 patients presenting with non-ST segment elevation myocardial infarction using invasive coronary angiography (ICA) as the reference method. The relation between the severity of disease by CCTA and a combined endpoint of death, re-hospitalization due to new myocardial infarction, or symptom-driven coronary revascularization was assessed...
July 1, 2016: Scandinavian Cardiovascular Journal: SCJ
John T Kelly, Annie K McClellan, Lynn V Joe, Ashley M Wright, Lawson T Lloyd, Gregory S Tschumper, Nathan I Hammer
The competition for binding and charge-transfer (CT) from the nitrogen containing heterocycle pyrimidine to either silver or to water in surface enhanced Raman spectroscopy (SERS) is discussed. The correlation between the shifting observed for vibrational normal modes and CT is analyzed both experimentally using Raman spectroscopy and theoretically using electronic structure theory. Discrete features in the Raman spectrum correspond to the binding of either water or silver to each of pyrimidine's nitrogen atoms with comparable frequency shifts...
September 19, 2016: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Li Liu, Pierre Eisenbrandt, Thomas Roland, Matthias Polkehn, Pierre-Olivier Schwartz, Kirsten Bruchlos, Beatrice Omiecienski, Sabine Ludwigs, Nicolas Leclerc, Elena Zaborova, Jérémie Léonard, Stéphane Méry, Irene Burghardt, Stefan Haacke
Conjugated donor-acceptor block co-oligomers that self-organize into D-A mesomorphic arrays have raised increasing interest due to their potential applications in organic solar cells. We report here a combined experimental and computational study of charge transfer (CT) state formation and recombination in isolated donor-spacer-acceptor oligomers based on bisthiophene-fluorene (D) and perylene diimide (A), which have recently shown to self-organize to give a mesomorphic lamellar structure at room temperature...
July 21, 2016: Physical Chemistry Chemical Physics: PCCP
Zilong Zheng, Jean-Luc Brédas, Veaceslav Coropceanu
Density functional theory (DFT) approaches based on range-separated hybrid functionals are currently methods of choice for the description of the charge-transfer (CT) states in organic donor/acceptor solar cells. However, these calculations are usually performed on small-size donor/acceptor complexes and as result do not account for electronic polarization effects. Here, using a pentacene/C60 complex as a model system, we discuss the ability of long-range corrected (LCR) hybrid functionals in combination with the polarizable continuum model (PCM) to determine the impact of the solid-state environment on the CT states...
July 7, 2016: Journal of Physical Chemistry Letters
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