24 research outputs found

    Elevated acute phase proteins affect pharmacokinetics in COVID-19 trials: Lessons from the CounterCOVID - imatinib study.

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    This study aimed to determine whether published pharmacokinetic (PK) models can adequately predict the PK profile of imatinib in a new indication, such as coronavirus disease 2019 (COVID-19). Total (bound + unbound) and unbound imatinib plasma concentrations obtained from 134 patients with COVID-19 participating in the CounterCovid study and from an historical dataset of 20 patients with gastrointestinal stromal tumor (GIST) and 85 patients with chronic myeloid leukemia (CML) were compared. Total imatinib area under the concentration time curve (AUC), maximum concentration (C <sub>max</sub> ) and trough concentration (C <sub>trough</sub> ) were 2.32-fold (95% confidence interval [CI] 1.34-3.29), 2.31-fold (95% CI 1.33-3.29), and 2.32-fold (95% CI 1.11-3.53) lower, respectively, for patients with CML/GIST compared with patients with COVID-19, whereas unbound concentrations were comparable among groups. Inclusion of alpha1-acid glycoprotein (AAG) concentrations measured in patients with COVID-19 into a previously published model developed to predict free imatinib concentrations in patients with GIST using total imatinib and plasma AAG concentration measurements (AAG-PK-Model) gave an estimated mean (SD) prediction error (PE) of -20% (31%) for total and -7.0% (56%) for unbound concentrations. Further covariate modeling with this combined dataset showed that in addition to AAG; age, bodyweight, albumin, CRP, and intensive care unit admission were predictive of total imatinib oral clearance. In conclusion, high total and unaltered unbound concentrations of imatinib in COVID-19 compared to CML/GIST were a result of variability in acute phase proteins. This is a textbook example of how failure to take into account differences in plasma protein binding and the unbound fraction when interpreting PK of highly protein bound drugs, such as imatinib, could lead to selection of a dose with suboptimal efficacy in patients with COVID-19

    Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

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    A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk

    The DUNE far detector vertical drift technology. Technical design report

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    DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

    Contrast-matching small-angle neutron scattering to monitor the accessibility of solvents to the porosity of coked FCC catalysts

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    Small-angle neutron scattering (SANS) has been performed on fresh and deactivated fluid catalytic cracking (FCC) equilibrium catalysts. The catalysts were coked using a vacuum gas oil feed and stripped for varying periods of time in standard microactivity test (MAT) and fluidized-bed reactors. BET surface areas and contrast-matching SANS were measured on these samples to elucidate the influence of coke on the catalyst porosity. It was found that significant contrast matching could be obtained by mixing the catalyst with deuterated methanol, and there was good agreement between the gas adsorption and SANS results in terms of the mesoporosity. SANS indicated that the level of closed porosity is negligible in the fresh catalyst but significant in the deactivated catalysts and that the level decreases as the total coke content is reduced during stripping. Furthermore, the use of d-dodecane demonstrated that SANS can also provide information about sieving effects caused by the catalyst structure

    Secondary coking and cracking of shale oil vapors from pyrolysis or hydropyrolysis of a Kentucky Cleveland oil-shale in a 2-stage reactor

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    It is widely recognized that secondary reactions which are mainly associated with minerals during oil shale retorting have a marked influence on the product yields and compositions. To understand these phenomena more clearly, the secondary reactions of shale oil vapours from the pyrolysis (or hydropyrolysis) of Kentucky Cleveland oil shale were examined in a two-stage, fixed-bed reactor in flowing nitrogen or hydrogen at pressures of 0.1-15 MPa. The vapours from pyrolysis (first stage) were passed through a second stage containing combusted shale, upgrading catalyst or neither. Carbon conversion to volatile products in the first stage increased from 49% during thermal pyrolysis to 81% at 15 MPa H2 partial pressure. During thermal pyrolysis, total pressure had only a slight effect on carbon removal from the raw shale and subsequent deposition on to the porous solids in the second stage. Carbon deposition on to the combusted shale in the second stage was reduced to zero at 15 MPa H2 partial pressure. The n-alkane distributions of the oils as determined by gas chromatography clearly demonstrated that higher hydrogen pressure, contact with combusted shale, or both contributed to lower-molecular-weight products

    Sulfur- and nitrogen-containing phenol-formaldehyde co-resites for probing the thermal behaviour of heteroatomic forms in solid fuels

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    In order to probe the formation of sulfur- and nitrogen-containing gases during the pyrolysis and combustion of coals and other solid fuels, non-softening model substrates are required. In this respect, phenol-formaldehyde (PF) resins are ideal since they readily facilitate the incorporation of individual heteroatomic functions into a highly crosslinked matrix. A series of sulfur- and nitrogen-containing co-resites have been prepared using phenol with, as the second component, thiophene, dibenzothiophene, diphenylsulfide, benzyl phenyl sulfide, thioanisole, 8-hydroxyquinoline and 2-hydroxycarbazole. A mole ratio of 3 : 1 (phenol: heteroatom-containing component) was adopted in order to ensure that a reasonably high degree of crosslinking was achieved. Resoles containing diphenyldisulfide were also prepared but, due to the comparable bond strengths of the S-S and C-O linkages, a curing temperature of only 130 degrees C was used to avoid cleavage of the disulfide bond. The virtually complete elimination of ether and methylol functions from the resoles by curing at 200 degrees C was monitored by solid-state C-13 nuclear magnetic resonance (n.m.r.) spectroscopy. The resultant resites were also characterized by sulfur K-edge X-ray absorption near-edge structure (XANES.) spectroscopy, X-ray photoelectron spectroscopy (X.p.s.) and differential scanning calorimetry (d.s.c.). Simple air oxidation was found to selectively convert the aliphatic-bound sulfur to a mixture of sulfones and sulfoxides. Applications of the resites in fuel science are described
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