720 research outputs found
Disruption of nNOS-NOS1AP protein-protein interactions suppresses neuropathic pain in mice
Elevated N-methyl-D-aspartate receptor (NMDAR) activity is linked to central sensitization and chronic pain. However, NMDAR antagonists display limited therapeutic potential because of their adverse side effects. Novel approaches targeting the NR2B-PSD95-nNOS complex to disrupt signaling pathways downstream of NMDARs show efficacy in preclinical pain models. Here, we evaluated the involvement of interactions between neuronal nitric oxide synthase (nNOS) and the nitric oxide synthase 1 adaptor protein (NOS1AP) in pronociceptive signaling and neuropathic pain. TAT-GESV, a peptide inhibitor of the nNOS-NOS1AP complex, disrupted the in vitro binding between nNOS and its downstream protein partner NOS1AP but not its upstream protein partner postsynaptic density 95 kDa (PSD95). Putative inactive peptides (TAT-cp4GESV and TAT-GESVΔ1) failed to do so. Only the active peptide protected primary cortical neurons from glutamate/glycine-induced excitotoxicity. TAT-GESV, administered intrathecally (i.t.), suppressed mechanical and cold allodynia induced by either the chemotherapeutic agent paclitaxel or a traumatic nerve injury induced by partial sciatic nerve ligation. TAT-GESV also blocked the paclitaxel-induced phosphorylation at Ser15 of p53, a substrate of p38 MAPK. Finally, TAT-GESV (i.t.) did not induce NMDAR-mediated motor ataxia in the rotarod test and did not alter basal nociceptive thresholds in the radiant heat tail-flick test. These observations support the hypothesis that antiallodynic efficacy of an nNOS-NOS1AP disruptor may result, at least in part, from blockade of p38 MAPK-mediated downstream effects. Our studies demonstrate, for the first time, that disrupting nNOS-NOS1AP protein-protein interactions attenuates mechanistically distinct forms of neuropathic pain without unwanted motor ataxic effects of NMDAR antagonists
Further studies on relic neutrino asymmetry generation II: a rigorous treatment of repopulation in the adiabatic limit
We derive an approximate relic neutrino asymmetry evolution equation that
systematically incorporates repopulation processes from the full quantum
kinetic equations (QKEs). It is shown that in the collision dominant epoch, the
said equation reduces precisely to the expression obtained previously from the
static/adiabatic approximation. The present treatment thus provides a rigorous
justification for the seemingly incongruous assumptions of a negligible
repopulation function and instantaneous repopulation sometimes employed in
earlier works.Comment: RevTeX, 11 pages, no figure
No negative impact of Palliative sedation on relatives' experience of the dying phase and their wellbeing after the patient's death: An observational study
Background: Palliative sedation is the widely-used intervention of administering sedating agents to induce a state of unconsciousness to take away a dying patient's perception of otherwise irrelievable symptoms. However, it remains questionable whether this ethically complex intervention is beneficial for patients and whether the associated lack of communication in the last phase of life has a negative impact on relatives' wellbeing. Methods: An observational questionnaire study was conducted among relatives of a consecutive sample of patients who died a non-sudden death in the Erasmus MC Cancer Institute or in the hospice 'Laurens Cadenza' (both in Rotterdam) between 2010 and 2013. Results: Relatives filled in questionnaires regarding 151 patients who had been sedated and 90 patients who had not been sedated. The median time since all patients had passed away was 21 (IQR 14-32) months. No significant differences were found in relatives' assessments of the quality of end-of-life care, patients' quality of life in the last week before death and their quality of dying, between patients who did and did not receive sedation, or in relatives' satisfaction with their own life, their general health and their mental wellbeing after the patient's death. Conclusions: The use of sedation in these patients appears to have no negative effect on bereaved relatives' evaluation of the patient's dying phase, or on their own wellbeing after the patient's death
The constraint equations for the Einstein-scalar field system on compact manifolds
We study the constraint equations for the Einstein-scalar field system on
compact manifolds. Using the conformal method we reformulate these equations as
a determined system of nonlinear partial differential equations. By introducing
a new conformal invariant, which is sensitive to the presence of the initial
data for the scalar field, we are able to divide the set of free conformal data
into subclasses depending on the possible signs for the coefficients of terms
in the resulting Einstein-scalar field Lichnerowicz equation. For many of these
subclasses we determine whether or not a solution exists. In contrast to other
well studied field theories, there are certain cases, depending on the mean
curvature and the potential of the scalar field, for which we are unable to
resolve the question of existence of a solution. We consider this system in
such generality so as to include the vacuum constraint equations with an
arbitrary cosmological constant, the Yamabe equation and even (all cases of)
the prescribed scalar curvature problem as special cases.Comment: Minor changes, final version. To appear: Classical and Quantum
Gravit
Small molecule inhibitors of PSD95-nNOS protein-protein interactions as novel analgesics.
Aberrant increases in NMDA receptor (NMDAR) signaling contributes to central nervous system sensitization and chronic pain by activating neuronal nitric oxide synthase (nNOS) and generating nitric oxide (NO). Because the scaffolding protein postsynaptic density 95kDA (PSD95) tethers nNOS to NMDARs, the PSD95-nNOS complex represents a therapeutic target. Small molecule inhibitors IC87201 (EC5O: 23.94 µM) and ZL006 (EC50: 12.88 µM) directly inhibited binding of purified PSD95 and nNOS proteins in AlphaScreen without altering binding of PSD95 to ErbB4. Bot
Design of small molecule-responsive microRNAs based on structural requirements for Drosha processing
MicroRNAs (miRNAs) are prevalent regulatory RNAs that mediate gene silencing and play key roles in diverse cellular processes. While synthetic RNA-based regulatory systems that integrate regulatory and sensing functions have been demonstrated, the lack of detail on miRNA structure–function relationships has limited the development of integrated control systems based on miRNA silencing. Using an elucidated relationship between Drosha processing and the single-stranded nature of the miRNA basal segments, we developed a strategy for designing ligand-responsive miRNAs. We demonstrate that ligand binding to an aptamer integrated into the miRNA basal segments inhibits Drosha processing, resulting in titratable control over gene silencing. The generality of this control strategy was shown for three aptamer–small molecule ligand pairs. The platform can be extended to the design of synthetic miRNAs clusters, cis-acting miRNAs and self-targeting miRNAs that act both in cis and trans, enabling fine-tuning of the regulatory strength and dynamics. The ability of our ligand-responsive miRNA platform to respond to user-defined inputs, undergo regulatory performance tuning and display scalable combinatorial control schemes will help advance applications in biological research and applied medicine
Outpatient-Based Therapy of Oral Fludarabine and Subcutaneous Alemtuzumab for Asian Patients with Relapsed/Refractory Chronic Lymphocytic Leukemia
Background. Intravenous alemtuzumab and fludarabine are effective in combination for the treatment of chronic lymphocytic leukemia (CLL), but require hospital visits for intravenous injection. We performed a pilot study to assess the safety and efficacy of outpatient-based oral fludarabine with subcutaneous alemtuzumab (OFSA) for the treatment of relapsed/refractory CLL. Results. Depending on their response, patients were given two to six 28-day cycles of subcutaneous alemtuzumab 30 mg on days 1,3, and 5 and oral fludarabine 40 mg/m2/day for 5 days. Median patient age was 74. The lymphocyte counts of all five patients fell after the 1st cycle of treatment and reached normal/low levels on completion of 2 to 6 cycles of therapy. Platelet counts and hemoglobin were unaffected. All five patients achieved complete hematological remission, while two attained minimal residual disease negativity on 4-color flow cytometry. Conclusions. Our OFSA regimen was effective in elderly Asian patients with relapsed/refractory CLL, and it should be investigated further
Further studies on relic neutrino asymmetry generation I: the adiabatic Boltzmann limit, non-adiabatic evolution, and the classical harmonic oscillator analogue of the quantum kinetic equations
We demonstrate that the relic neutrino asymmetry evolution equation derived
from the quantum kinetic equations (QKEs) reduces to the Boltzmann limit that
is dependent only on the instantaneous neutrino number densities, in the
adiabatic limit in conjunction with sufficient damping. An original physical
and/or geometrical interpretation of the adiabatic approximation is given,
which serves as a convenient visual aid to understanding the sharply
contrasting resonance behaviours exhibited by the neutrino ensemble in opposing
collision regimes. We also present a classical analogue for the evolution of
the difference in and number densities which, in the
Boltzmann limit, is akin to the behaviour of the generic reaction with equal forward and reverse reaction rate constants. A
new characteristic quantity, the matter and collision-affected mixing angle of
the neutrino ensemble, is identified here for the first time. The role of
collisions is revealed to be twofold: (i) to wipe out the inherent
oscillations, and (ii) to equilibrate the and number
densities in the long run. Studies on non-adiabatic evolution and its possible
relation to rapid oscillations in lepton number generation also feature, with
the introduction of an adiabaticity parameter for collision-affected
oscillations.Comment: RevTeX, 38 pages including 8 embedded figure
Energy-dependent solar neutrino flux depletion in the Exact Parity Model and implications for SNO, SuperKamiokande and BOREXINO
Energy-dependent solar neutrino flux reduction caused by the
Mikheyev-Smirnov-Wolfenstein (MSW) effect is applied to the Exact Parity Model.
Several scenarios are possible, depending on the region of parameter space
chosen. The interplay between intergenerational MSW transitions and vacuum
``intragenerational'' ordinary-mirror neutrino oscillations is discussed.
Expectations for the ratio of charged to neutral current event rates at the
Sudbury Neutrino Observatory (SNO) are estimated. The implications of the
various scenarios for the Boron neutrino energy spectrum and BOREXINO are
briefly discussed. The consequences of MSW-induced solar neutrino depletion
within the Exact Parity Model differ in interesting ways from the standard
and cases. The physical causes of
these differences are determined.Comment: 43 pages, 8 figures, RevTeX; to appear in Phys. Rev. D, accepted
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