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Level of evidence used in recommendations by the National Comprehensive Cancer Network (NCCN) guidelines beyond Food and Drug Administration approvals.
BackgroundA previous analysis of 113 National Comprehensive Cancer NetworkÂź (NCCNÂź) recommendations reported that NCCN frequently recommends beyond Food and Drug Administration (FDA)-approved indications (44 off-label recommendations) and claimed that the evidence for these recommendations was weak.MethodsIn order to determine the strength of the evidence, we carried out an in-depth re-analysis of the 44 off-label recommendations listed in the NCCN Clinical Practice Guidelines in Oncology (NCCN GuidelinesÂź).ResultsOf the 44 off-label recommendations, 14 were later approved by the FDA and/or are supported by randomized controlled trial (RCT) data. In addition, 13 recommendations were either very minor extrapolations from the FDA label (nâ=â8) or were actually on-label (nâ=â5). Of the 17 remaining extrapolations, 8 were for mechanism-based agents applied in rare cancers or subsets with few available treatment options (median response rate = 43%), 7 were based on non-RCT data showing significant efficacy (>50% response rates), and 2 were later removed from the NCCN Guidelines because newer therapies with better activity and/or safety became available.ConclusionOff-label drug use is a frequent component of care for patients with cancer in the United States. Our findings indicate that when the NCCN recommends beyond the FDA-approved indications, the strength of the evidence supporting such recommendations is robust, with a significant subset of these drugs later becoming FDA approved or supported by RCT. Recommendations without RCT data are often for mechanism-based drugs with high response rates in rare cancers or subsets without effective therapies
Going Straight: The Politics of Time and Space in David Eldridgeâs Incomplete and Random Acts of Kindness
Amelia Howe Kritzer states that a contemporary British play is commonly thought of as political if it presents "a political issue or comments on what is already perceived as a political issue" (10). Since 1989, however, the economic and political system in the UK has become increasingly monologic. In such a monologic political system, Shavian dialogic forms of political theatre, which present a dialectical discussion of a political issue, lose their efficacy. As a result, some British playwrights have moved toward more interventionist strategies of political engagement, which involve our lived experience of social structures through their dramaturgy. These plays re-order normative representations of social structures, of offering a symbolic re-ordering of social structures within their form. As such, their form represents what Adorno terms, "and analogy of that other condition which should be" (194). David Harvey argues that in late capitalist society, our experience of time and space has become increasingly compressed. Consequently, our temporary axis of succession, which constitutes the fundamental organisation of Shavian drama, no longer reflects our lived experience of time in the world outside the theatre. Therefore, plays that re-order structures of time and space have political efficacy in that they expose a gap between representations of time and space as linear and concrete and our lived experience of time and space as compressed. This essay argues that David Eldridge's 'Incomplete and Random Acts of Kindness' articulates a complete breakdown in the temporal axis of succession in its structure. Its dramaturgy reflects the experience of space-time compression. Thus, it is a highly political play, not on the basis of its content, but in terms of the way in which its structure mediates and negotiates our lived experience of social structures under the pressures of late capitalism
Feedback modeling of non-esterified fatty acids in rats after nicotinic acid infusions
A feedback model was developed to describe the tolerance and oscillatory rebound seen in non-esterified fatty acid (NEFA) plasma concentrations following intravenous infusions of nicotinic acid (NiAc) to male Sprague-Dawley rats. NiAc was administered as an intravenous infusion over 30 min (0, 1, 5 or 20 Όmol kgâ1 of body weight) or over 300 min (0, 5, 10 or 51 Όmol kgâ1 of body weight), to healthy rats (n = 63), and serial arterial blood samples were taken for measurement of NiAc and NEFA plasma concentrations. Data were analyzed using nonlinear mixed effects modeling (NONMEM). The disposition of NiAc was described by a two-compartment model with endogenous turnover rate and two parallel capacity-limited elimination processes. The plasma concentration of NiAc was driving NEFA (R) turnover via an inhibitory drug-mechanism function acting on the formation of NEFA. The NEFA turnover was described by a feedback model with a moderator distributed over a series of transit compartments, where the first compartment (M1) inhibited the formation of R and the last compartment (MN) stimulated the loss of R. All processes regulating plasma NEFA concentrations were assumed to be captured by the moderator function. The potency, IC50, of NiAc was 45 nmol Lâ1, the fractional turnover rate kout was 0.41 L mmolâ1 minâ1 and the turnover rate of moderator ktol was 0.027 minâ1. A lower physiological limit of NEFA was modeled as a NiAc-independent release (kcap) of NEFA into plasma and was estimated to 0.032 mmol Lâ1 minâ1. This model can be used to provide information about factors that determine the time-course of NEFA response following different modes, rates and routes of administration of NiAc. The proposed model may also serve as a preclinical tool for analyzing and simulating drug-induced changes in plasma NEFA concentrations after treatment with NiAc or NiAc analogues
State Dependent Effective Interaction for the Hyperspherical Formalism with Noncentral Forces
The recently developed effective interaction method for the hyperspherical
harmonic formalism is extended to noncentral forces. Binding energies and radii
of three- and four-body nuclei are calculated with AV6 and AV14 NN potentials.
Excellent results for the convergence of the expansion are found, particularly
for the three-nucleon system. Due to the higher density the convergence rate is
a bit slower for the alpha particle. In comparison to central potential models
there is only a very slight deterioration of the convergence due the tensor
force, while other potential terms have no visible effect on the convergence.
The obtained values for binding energy and radii also agree well with the
results in the literature obtained with other few-body techniques.Comment: LaTeX, 12 pages, 6 ps figures, Figures in correct order in this
replacemen
Low-lying spectrum of the Y-string three-quark potential using hyper-spherical coordinates
We calculate the energies of three-quark states with definite permutation
symmetry (i.e. of SU(6) multiplets) in the N=0,1,2 shells, confined by the
Y-string three-quark potential. The exact Y-string potential consists of one,
so-called three-string term, and three angle-dependent two-string terms. Due to
this technical complication we treat the problem at three increasingly accurate
levels of approximation: 1) the (approximate) three-string potential expanded
to first order in trigonometric functions of hyper-spherical angles; 2) the
(approximate) three-string potential to all orders in the power expansion in
hyper-spherical harmonics, but without taking into account the transition(s) to
two-string potentials; 3) the exact minimal-length string potential to all
orders in power expansion in hyper-spherical harmonics, and taking into account
the transition(s) to two-string potentials. We show the general trend of
improvement %convergence of these approximations: The exact non-perturbative
corrections to the total energy are of the order of one per cent, as compared
with approximation 2), yet the exact energy differences between the
-plets are shifted to 2:2:0.9,
from the Bowler and Tynemouth separation rule 2:2:1, which is obeyed by
approximation 2) at the one per cent level. The precise value of the energy
separation of the first radial excitation ("Roper") -plet
from the -plet depends on the approximation, but does not become
negative, i.e. the "Roper" remains heavier than the odd-parity
-plet in all of our approximations.Comment: 19 pages, 6 figure
Non-perturbative Gluons and Pseudoscalar Mesons in Baryon Spectroscopy
We study baryon spectroscopy including the effects of pseudoscalar meson
exchange and one gluon exchange potentials between quarks, governed by
. The non-perturbative, hyperspherical method calculations show that
one can obtain a good description of the data by using a quark-meson coupling
constant that is compatible with the measured pion-nucleon coupling constant,
and a reasonably small value of .Comment: 12 pages; Submitted to Phys. Rev. C. Rapid Communication
BDM Dark Matter: CDM with a core profile and a free streaming scale
We present a new dark matter model BDM which is an hybrid between hot dark
matter HDM and cold dark matter CDM, in which the BDM particles behave as HDM
above the energy scale E_c and as CDM below this scale. Evolution of structure
formation is similar to that of CDM model but BDM predicts a nonvanishing free
streaming l_fs scale and a inner galaxy core radius r_core, both quantities
determined in terms of a single parameter E_c, which corresponds to the phase
transition energy scale of the subjacent elementary particle model. For
energies above E_c or for a scale factor a smaller then a_c, with a<a_c<a_{eq},
the particles are massless and rho redshifts as radiation. However, once the
energy becomes E\leq E_c or a>a_c then the BDM particles acquire a large mass
through a non perturbative mechanism, as baryons do, and rho redshifts as
matter with the particles having a vanishing velocity. Typical energies are
E_c=O(10-100) eV giving a l_fs \propto E_c^{-4/3}\lesssim Mpc and m_fs\propto
E_c^{-4}\lesssim 10^9 M\odot. A l_fs\neq 0, r_core\neq 0 help to resolve some
of the shortcomings of CDM such as overabundance substructure in CDM halos and
numerical fit to rotation curves in dwarf spheroidal and LSB galaxies. Finally,
our BDM model and the phase transition scale E_c can be derived from particle
physics.Comment: 7 pages, 8 figure
On three-manifolds dominated by circle bundles
We determine which three-manifolds are dominated by products. The result is
that a closed, oriented, connected three-manifold is dominated by a product if
and only if it is finitely covered either by a product or by a connected sum of
copies of the product of the two-sphere and the circle. This characterization
can also be formulated in terms of Thurston geometries, or in terms of purely
algebraic properties of the fundamental group. We also determine which
three-manifolds are dominated by non-trivial circle bundles, and which
three-manifold groups are presentable by products.Comment: 12 pages; to appear in Math. Zeitschrift; ISSN 1103-467
First and second order optimality conditions for optimal control problems of state constrained integral equations
This paper deals with optimal control problems of integral equations, with
initial-final and running state constraints. The order of a running state
constraint is defined in the setting of integral dynamics, and we work here
with constraints of arbitrary high orders. First and second-order necessary
conditions of optimality are obtained, as well as second-order sufficient
conditions
Pentaquark spectrum in string dynamics
The masses of and pentaquarks are evaluated in a
framework of the Effective Hamiltonian approach to QCD using the Jaffe-Wilczek
approximation. The mass of the state is found to
be MeV higher than the observed mass.Comment: 6 pages, 1 figure included, LaTeX2e; several references added;
misprints corrected; to appear in Physics Letters
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