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A pragmatic patient-reported outcome strategy for rare disease clinical trials: application of the EORTC item library to myelodysplastic syndromes, chronic myelomonocytic leukemia, and acute myeloid leukemia.
BackgroundNovel, pragmatic, patient-centered strategies are needed to ensure fit-for-purpose patient-reported outcomes (PRO) instruments in clinical trial research for rare diseases such as myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), and chronic myelomonocytic leukemia (CMML). The objective of the current study was to select supplemental items to add to the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life-Core 30 (QLQ-C30) to ensure content coverage of all important clinical concepts in patients with higher-risk (HR) MDS, low-blast count (LB) AML, and CMML, thus, improving the instrument's ability to detect clinically meaningful treatment benefit for this context of use.MethodsOur mixed methods approach comprised literature review, clinician consultation (n = 3), and qualitative and quantitative analysis of two stages of patient interview data (n = 14, n = 18) to select library bank items to supplement a generic cancer PRO, the EORTC QLQ-C30.ResultsUnique symptom (n = 54) and impact (n = 72) concepts were organized into conceptual frameworks of treatment benefit, compared with EORTC QLQ-C30 items and conceptual gaps identified. Supplemental items (n = 13) addressing those gaps were selected from the EORTC Item Library and tested with patients. Supplemental item endorsement frequencies met World Health Organization Quality of Life criteria, suggesting good targeting and relevance for this sample. However, three supplemental items were confirmed as problematic based upon cognitive debriefing results, and expert clinical consultations. Ultimately, 10 supplemental items (n = 7 symptom; n = 3 impact) were selected for the MDS/AML/CMML context.ConclusionSupplemental items were selected to enhance the conceptual coverage of the EORTC QLQ-C30 in the areas of fatigue, shortness of breath, and functioning
Evidence for a non-universal stellar initial mass function in low-redshift high-density early-type galaxies
We determine an absolute calibration of stellar mass-to-light ratios for the
densest \simeq 3% of early-type galaxies in the local universe (redshift
z\simeq 0.08) from SDSS DR7. This sample of \sim 4000 galaxies has, assuming a
Chabrier IMF, effective stellar surface densities, Sigma_e > 2500 M_sun/pc^2,
stellar population synthesis (SPS) stellar masses log_10(M_sps/M_sun)<10.8, and
aperture velocity dispersions of sigma_ap=168^{+37}_{-34} km/s (68% range). In
contrast to typical early-type galaxies, we show that these dense early-type
galaxies follow the virial fundamental plane, which suggests that
mass-follows-light. With the additional assumption that any dark matter does
not follow the light, the dynamical masses of dense galaxies provide a direct
measurement of stellar masses. Our dynamical masses (M_dyn), obtained from the
spherical Jeans equations, are only weakly sensitive to the choice of
anisotropy (\beta) due to the relatively large aperture of the SDSS fiber for
these galaxies: R_ap \simeq 1.5 R_e. Assuming isotropic orbits (\beta=0) we
find a median log_{10} (M_dyn/M_sps) = 0.233 \pm 0.003, consistent with a
Salpeter IMF, while more bottom heavy IMFs and standard Milky-Way IMFs are
strongly disfavored. Our results are consistent with, but do not require, a
dependence of the IMF on dynamical mass or velocity dispersion. We find
evidence for a color dependence to the IMF such that redder galaxies have
heavier IMFs with M_dyn/M_sps \propto (g-r)^{1.13\pm0.09}. This may reflect a
more fundamental dependence of the IMF on the age or metallicity of a stellar
population, or the density at which the stars formed.Comment: 5 pages, 6 figures, accepted to MNRAS Letters, minor changes to
previous versio
Prescription drug monitoring program data tracking of opioid addiction treatment outcomes in integrated dual diagnosis care involving injectable naltrexone
BACKGROUND AND OBJECTIVES: Fourfold increases in opioid prescribing and dispensations over 2 decades in the U.S. has paralleled increases in opioid addictions and overdoses, requiring new preventative, diagnostic, and treatment strategies. This study examines Prescription Drug Monitoring Program (PDMP) tracking as a novel measure of opioid addiction treatment outcomes in a university-affiliated integrated mental health-addiction treatment clinic.
METHODS: Repeated measure parametrics examined PDMP and urine drug screening (UDS) data before and after first injection for all patients (N = 68) who received at least one long-acting naltrexone injection (380 mg/IM) according to diagnostic groupings of having either (i) alcohol (control); (ii) opioid; or (iii) combined alcohol and opioid use disorders.
RESULTS: There were no group differences post-injection in treatment days, injections delivered, or treatment service encounters. UDS and PDMP measures of opioid exposures were greater in opioid compared to alcohol-only patients. Post-first injection, UDS's positive for opioids declined (p < .05) along with PDMP measures of opioid prescriptions (p < .001), doses (p < .01), types (p < .001), numbers of dispensing prescribers (p < .001) and pharmacies (p < .001). Opioid patients without alcohol disorders showed the best outcomes with 50% to 80% reductions in PDMP-measures of opioids, down to levels of alcohol-only patients.
CONCLUSIONS: This study shows PDMP utility for measuring opioid addiction treatment outcomes, supporting the routine use of PDMPs in clinical and research settings.
SCIENTIFIC SIGNIFICANCE: These findings demonstrate that opioid addiction in patients with complex addictions and mental illnesses comorbidities can show effective treatment responses as measured by PDMP tracking of decreases in opioid prescriptions to those patients. (Am J Addict 2016;25:557-564)
Successful use of axonal transport for drug delivery by synthetic molecular vehicles
We report the use of axonal transport to achieve intraneural drug delivery. We constructed a novel tripartite complex of an axonal transport facilitator conjugated to a linker molecule bearing up to a hundred reversibly attached drug molecules. The complex efficiently enters nerve terminals after intramuscular or intradermal administration and travels within axonal processes to neuron cell bodies. The tripartite agent provided 100-fold amplification of saturable neural uptake events, delivering multiple drug molecules per complex. _In vivo_, analgesic drug delivery to systemic and to non-targeted neural tissues was greatly reduced compared to existing routes of administration, thus exemplifying the possibility of specific nerve root targeting and effectively increasing the potency of the candidate drug gabapentin 300-fold relative to oral administration
The effect of Warm Dark Matter on galaxy properties: constraints from the stellar mass function and the Tully-Fisher relation
In this paper we combine high resolution N-body simulations with a semi
analytical model of galaxy formation to study the effects of a possible Warm
Dark Matter (WDM) component on the observable properties of galaxies. We
compare three WDM models with a dark matter mass of 0.5, 0.75 and 2.0 keV, with
the standard Cold Dark Matter case. For a fixed set of parameters describing
the baryonic physics the WDM models predict less galaxies at low (stellar)
masses, as expected due to the suppression of power on small scales, while no
substantial difference is found at the high mass end. However these differences
in the stellar mass function, vanish when different set of parameters are used
to describe the (largely unknown) galaxy formation processes. We show that is
possible to break this degeneracy between DM properties and the
parameterization of baryonic physics by combining observations on the stellar
mass function with the Tully-Fisher relation (the relation between stellar mass
and the rotation velocity at large galactic radii as probed by resolved HI
rotation curves). WDM models with a too warm candidate (m<0.75 keV) cannot
simultaneously reproduce the stellar mass function and the Tully-Fisher
relation. We conclude that accurate measurements of the galaxy stellar mass
function and the link between galaxies and dark matter haloes down to the very
low-mass end can give very tight constraints on the nature of DM candidates.Comment: 8 pages, 5 figures, minor changes, accepted for publication on Ap
Optimal operation of the Western Link embedded HVDC connection
The Western Link is a new point-to-point embedded HVDC connection due to be commissioned in Great Britain in 2018. This paper investigates the optimal loading of the Western Link with respect to the wider transmission system. The work modelled a representation of behaviour of the wholesale market and system operator actions using mathematical optimisation in the form of an economic dispatch followed by an AC optimal power flow. A range of different system cases was studied using: a representative high voltage transmission network of Great Britain; system planned outages on AC circuits in parallel with the Western Link; system contingencies; and two possible post-contingency Western Link loading rules. It was concluded from the cases studied that the optimal dispatch of power on the Western Link is an affine function of power flow in the parallel AC circuits, modulated by system planned outages and the thermal rating of the Western Link
Selective breeding for high alcohol consumption and response to nicotine: locomotor activity, dopaminergic in the mesolimbic system, and innate genetic differences in male and female alcohol-preferring, non-preferring, and replicate lines of high-alcohol drinking and low-alcohol drinking rats
Rationale
There is evidence for a common genetic link between alcohol and nicotine dependence. Rodents selectively bred for high alcohol consumption/responsivity are also more likely to self-administer nicotine than controls.
Objectives
The experiments examined the response to systemic nicotine, the effects of nicotine within the drug reward pathway, and innate expression of nicotine-related genes in a brain region regulating drug reward/self-administration in multiple lines of rats selectively bred for high and low alcohol consumption.
Methods
The experiments examined the effects of systemic administration of nicotine on locomotor activity, the effects of nicotine administered directly into the (posterior ventral tegmental area; pVTA) on dopamine (DA) release in the nucleus accumbens shell (AcbSh), and innate mRNA levels of acetylcholine receptor genes in the pVTA were determined in 6 selectively bred high/low alcohol consuming and Wistar rat lines.
Results
The high alcohol-consuming rat lines had greater nicotine-induced locomotor activity compared to low alcohol-consuming rat lines. Microinjections of nicotine into the pVTA resulted in DA release in the AcbSh with the dose response curves for high alcohol-consuming rats shifted leftward and upward. Genetic analysis of the pVTA indicated P rats expressed higher levels of α2 and β4.
Conclusion
Selective breeding for high alcohol preference resulted in a genetically divergent behavioral and neurobiological sensitivity to nicotine. The observed behavioral and neurochemical differences between the rat lines would predict an increased likelihood of nicotine reinforcement. The data support the hypothesis of a common genetic basis for drug addiction and identifies potential receptor targets
PyATMOS: A Scalable Grid of Hypothetical Planetary Atmospheres
Cloud computing offers an opportunity to run compute-resource intensive
climate models at scale by parallelising model runs such that datasets useful
to the exoplanet community can be produced efficiently. To better understand
the statistical distributions and properties of potentially habitable planetary
atmospheres we implemented a parallelised climate modelling tool to scan a
range of hypothetical atmospheres.Starting with a modern day Earth atmosphere,
we iteratively and incrementally simulated a range of atmospheres to infer the
landscape of the multi-parameter space, such as the abundances of biological
mediated gases (\ce{O2}, \ce{CO2}, \ce{H2O}, \ce{CH4}, \ce{H2}, and \ce{N2})
that would yield `steady state' planetary atmospheres on Earth-like planets
around solar-type stars. Our current datasets comprises of \numatmospheres
simulated models of exoplanet atmospheres and is available publicly on the NASA
Exoplanet Archive. Our scalable approach of analysing atmospheres could also
help interpret future observations of planetary atmospheres by providing
estimates of atmospheric gas fluxes and temperatures as a function of altitude.
Such data could enable high-throughput first-order assessment of the potential
habitability of exoplanetary surfaces and sepcan be a learning dataset for
machine learning applications in the atmospheric and exoplanet science domain.Comment: 9 pages, 6 figure
Gravitational Instabilities, Chondrule Formation, and the FU Orionis Phenomenon
Using analytic arguments and numerical simulations, we examine whether
chondrule formation and the FU Orionis phenomenon can be caused by the
burst-like onset of gravitational instabilities (GIs) in dead zones. At least
two scenarios for bursting dead zones can work, in principle. If the disk is on
the verge of fragmention, GI activation near to 5 AU can produce
chondrule-forming shocks, at least under extreme conditions. Mass fluxes are
also high enough during the onset of GIs to suggest that the outburst is
related to an FU Orionis phenomenon. This situation is demonstrated by
numerical simulations. In contrast, as supported by analytic arguments, if the
burst takes place close to AU, then even low pitch angle spiral waves
can create chondrule-producing shocks and outbursts. We also study the
stability of the massive disks in our simulations against fragmentation and
find that although disk evolution is sensitive to changes in opacity, the disks
we study do not fragment, even at high resolution and even for extreme
assumptions.Comment: To appear in Ap
The baryonic Tully-Fisher relation and galactic outflows
Most of the baryons in the Universe are not in the form of stars and cold gas
in galaxies. Galactic outflows driven by supernovae/stellar winds are the
leading mechanism for explaining this fact. The scaling relation between galaxy
mass and outer rotation velocity (also known as the baryonic Tully-Fisher
relation, BTF) has recently been used as evidence against this viewpoint. We
use a LCDM based semi-analytic disk galaxy formation model to investigate these
claims. In our model, galaxies with less efficient star formation and higher
gas fractions are more efficient at ejecting gas from galaxies. This is due to
the fact that galaxies with less efficient star formation and higher gas
fractions tend to live in dark matter haloes with lower circular velocities,
from which less energy is required to escape the potential well. In our model
the intrinsic scatter in the BTF is 0.15 dex, and mostly reflects scatter in
dark halo concentration. The observed scatter, equal to 0.24 dex, is dominated
by measurement errors. The best estimate for the intrinsic scatter is that it
is less than 0.15 dex, and thus our LCDM based model (which does not include
all possible sources of scatter) is only just consistent with this. In our
model, gas rich galaxies, at fixed virial velocity (V_vir), with lower stellar
masses have lower baryonic masses. This is consistent with the expectation that
galaxies with lower stellar masses have had less energy available to drive an
outflow. However, when the outer rotation velocity (V_flat) is used the
correlation has the opposite sign, with a slope in agreement with observations.
This is due to scatter in the relation between V_flat and V_vir. In summary,
contrary to some previous claims, we show that basic features of the BTF are
consistent with a LCDM based model in which the low efficiency of galaxy
formation is determined by galactic outflows.Comment: 7 pages, 4 figures, accepted to MNRA
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