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Current and Future Issues in the Development of Spinal Agents for the Management of Pain.
Targeting analgesic drugs for spinal delivery reflects the fact that while the conscious experience of pain is mediated supraspinally, input initiated by high intensity stimuli, tissue injury and/or nerve injury is encoded at the level of the spinal dorsal horn and this output informs the brain as to the peripheral environment. This encoding process is subject to strong upregulation resulting in hyperesthetic states and downregulation reducing the ongoing processing of nociceptive stimuli reversing the hyperesthesia and pain processing. The present review addresses the biology of spinal nociceptive processing as relevant to the effects of intrathecally-delivered drugs in altering pain processing following acute stimulation, tissue inflammation/injury and nerve injury. The review covers i) the major classes of spinal agents currently employed as intrathecal analgesics (opioid agonists, alpha 2 agonists; sodium channel blockers; calcium channel blockers; NMDA blockers; GABA A/B agonists; COX inhibitors; ii) ongoing developments in the pharmacology of spinal therapeutics focusing on less studied agents/targets (cholinesterase inhibition; Adenosine agonists; iii) novel intrathecal targeting methodologies including gene-based approaches (viral vectors, plasmids, interfering RNAs); antisense, and toxins (botulinum toxins; resniferatoxin, substance P Saporin); and iv) issues relevant to intrathecal drug delivery (neuraxial drug distribution), infusate delivery profile, drug dosing, formulation and principals involved in the preclinical evaluation of intrathecal drug safety
The role of cell-cell adhesion in wound healing
We present a stochastic model which describes fronts of cells invading a
wound. In the model cells can move, proliferate, and experience cell-cell
adhesion. We find several qualitatively different regimes of front motion and
analyze the transitions between them. Above a critical value of adhesion and
for small proliferation large isolated clusters are formed ahead of the front.
This is mapped onto the well-known ferromagnetic phase transition in the Ising
model. For large adhesion, and larger proliferation the clusters become
connected (at some fixed time). For adhesion below the critical value the
results are similar to our previous work which neglected adhesion. The results
are compared with experiments, and possible directions of future work are
proposed.Comment: to appear in Journal of Statistical Physic
Selection of ULIRGs in Infrared and Submm Surveys
We examine the selection characteristics of infrared and sub-mm surveys with
IRAS, Spitzer, BLAST, Herschel and SCUBA and identify the range of dust
temperatures these surveys are sensitive to, for galaxies in the ULIRG
luminosity range (12<log(LIR)<13), between z=0 and z=4. We find that the extent
of the redshift range over which surveys are unbiased is a function of the
wavelength of selection, flux density limit and ULIRG luminosity. Short
wavelength (<200{\mu}m) surveys with IRAS, Spitzer/MIPS and Herschel/PACS are
sensitive to all SED types in a large temperature interval (17-87K), over a
substantial fraction of their accessible redshift range. On the other hand,
long wavelength (>200{\mu}m) surveys with BLAST, Herschel/ SPIRE and SCUBA are
significantly more sensitive to cold ULIRGs, disfavouring warmer SEDs even at
low redshifts. We evaluate observations in the context of survey selection
effects, finding that the lack of cold ULIRGs in the local (z<0.1) Universe is
not a consequence of selection and that the range of ULIRG temperatures seen
locally is only a subset of a much larger range which exists at high redshift.
We demonstrate that the local luminosity-temperature (L-T) relation, which
indicates that more luminous sources are also hotter, is not applicable in the
distant Universe when extrapolated to the ULIRG regime, because the scatter in
observed temperatures is too large. Finally, we show that the difference
between the ULIRG temperature distributions locally and at high redshift is not
the result of galaxies becoming colder due to an L-T relation which evolves as
a function of redshift. Instead, they are consistent with a picture where the
evolution of the infrared luminosity function is temperature dependent, i.e.
cold galaxies evolve at a faster rate than their warm counterparts.Comment: 11 pages, 6 figures, accepted for publication in MNRA
Quantum Mott Transition and Multi-Furcating Criticality
Phenomenological theory of the Mott transition is presented. When the
critical temperature of the Mott transition is much higher than the quantum
degeneracy temperature, the transition is essentially described by the Ising
universality class. Below the critical temperature, phase separation or
first-order transition occurs. However, if the critical point is involved in
the Fermi degeneracy region, a marginal quantum critical point appears at zero
temperature. The originally single Mott critical point generates subsequent
many unstable fixed points through various Fermi surface instabilities induced
by the Mott criticality characterized by the diverging charge susceptibility or
doublon susceptibility. This occurs in marginal quantum-critical region.
Charge, magnetic and superconducting instabilitites compete severely under
these critical charge fluctuations. The quantum Mott transition triggers
multi-furcating criticality, which goes beyond the conventional concept of
multicriticality in quantum phase transitions. Near the quantum Mott
transition, the criticality generically drives growth of inhomogeneous
structure in the momentum space with singular points of flat dispersion on the
Fermi surface. The singular points determine the quantum dynamics of the Mott
transition by the dynamical exponent . We argue that many of
filling-control Mott transitions are classified to this category. Recent
numerical results as well as experimental results on strongly correlated
systems including transition metal oxides, organic materials and He layer
adsorbed on a substrate are consistently analyzed especially in two-dimensional
systems.Comment: 28 pages including 2 figure
Improved Measurement of the Partial-Rate CP Asymmetry in B+ -> K0pi+ and B- -> K0bar pi- Decays
We report an improved measurement of the partial-rate CP asymmetry in B+ =>
K0pi+ and B- => K0bar pi- decays. The analysis is based on a data sample of 85
million BBbar pairs collected at the Upsilon(4S) resonance with the Belle
detector at the KEKB e+ e- storage ring. We measure Acp(K0pi+-) = 0.07^{+0.09
+0.01}_{-0.08 -0.03}, where the first and second errors are statistical and
systematic, respectively; the corresponding 90% confidence-level interval is
-0.10 < Acp(K0pi+-) < 0.22 .Comment: 7 pages, 8 figures, submitted to Phys. Rev.
Improved Measurements of Branching Fractions for B->Kpi, pipi and KK Decays
We report improved measurements of branching fractions for ,
, and decays based on a data sample of 85.0
million pairs collected at the resonance with the
Belle detector at the KEKB storage ring. This data sample is almost
three times larger than the sample previously used. We observe clear signals
for , and decays and set upper limits on
decays. The results can be used to give model-dependent
constraints on the CKM angle , as well as limits on the hadronic
uncertainty in the time-dependent analysis of the angle .Comment: 10 pages, 1 figure, 4 tables. Submitted to Phys. Rev. D Rapid
Communications. Several corrections were mad
Study of B meson decays to three-body charmless hadronic final states
We report results of a study of charmless B meson decays to three-body KPiPi,
KKPi and KKK final states. Measurements of branching fractions for B decays to
K+0Pi+Pi-, K+K+K-, K0K+K-, KsKsK+ and KsKsKs final states are presented. The
decays B0=>K0K+K-, B+=>KsKsK+ and B0=>KsKsKs are observed for the first time.
We also report evidence for B+=>K+K-Pi+ decay. For the three-body final states
K0K+K-, KsKsPi+, K+K+Pi- and K-Pi+Pi+ 90% confidence level upper limits are
reported. Finally, we discuss the possibility of using the three-body
B0=>KsK+K- decay for CP violation studies. The results are obtained with a 78
fb^-1 data sample collected at the Y(4S) resonance by the Belle detector
operating at the KEKB asymmetric energy e+e- collider.Comment: 15 pages, 6 figures. To be submitted to PR
Measurement of Semileptonic Branching Fractions of B Mesons to Narrow D** States
Using the data accumulated in 2002-2004 with the DO detector in
proton-antiproton collisions at the Fermilab Tevatron collider with
centre-of-mass energy 1.96 TeV, the branching fractions of the decays B ->
\bar{D}_1^0(2420) \mu^+ \nu_\mu X and B -> \bar{D}_2^{*0}(2460) \mu^+ \nu_\mu X
and their ratio have been measured: BR(\bar{b}->B) \cdot BR(B-> \bar{D}_1^0
\mu^+ \nu_\mu X) \cdot BR(\bar{D}_1^0 -> D*- pi+) =
(0.087+-0.007(stat)+-0.014(syst))%; BR(\bar{b}->B)\cdot BR(B->D_2^{*0} \mu^+
\nu_\mu X) \cdot BR(\bar{D}_2^{*0} -> D*- \pi^+) =
(0.035+-0.007(stat)+-0.008(syst))%; and (BR(B -> \bar{D}_2^{*0} \mu^+ \nu_\mu
X)BR(D2*0->D*- pi+)) / (BR(B -> \bar{D}_1^{0} \mu^+ \nu_\mu X)\cdot
BR(\bar{D}_1^{0}->D*- \pi^+)) = 0.39+-0.09(stat)+-0.12(syst), where the charge
conjugated states are always implied.Comment: submitted to Phys. Rev. Let
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