3,029 research outputs found
Measurements of Grain Motion in a Dense, Three-Dimensional Granular Fluid
We have used an NMR technique to measure the short-time, three-dimensional
displacement of grains in a system of mustard seeds vibrated vertically at 15g.
The technique averages over a time interval in which the grains move
ballistically, giving a direct measurement of the granular temperature profile.
The dense, lower portion of the sample is well described by a recent
hydrodynamic theory for inelastic hard spheres. Near the free upper surface the
mean free path is longer than the particle diameter and the hydrodynamic
description fails.Comment: 4 pages, 4 figure
Using normalisation process theory to understand barriers and facilitators to implementing mindfulness-based stress reduction for people with multiple sclerosis
Objectives:
To study barriers and facilitators to implementation of mindfulness-based stress reduction for people with multiple sclerosis.
Methods:
Qualitative interviews were used to explore barriers and facilitators to implementation of mindfulness-based stress reduction, including 33 people with multiple sclerosis, 6 multiple sclerosis clinicians and 2 course instructors. Normalisation process theory provided the underpinning conceptual framework. Data were analysed deductively using normalisation process theory constructs (coherence, cognitive participation, collective action and reflexive monitoring).
Results:
Key barriers included mismatched stakeholder expectations, lack of knowledge about mindfulness-based stress reduction, high levels of comorbidity and disability and skepticism about embedding mindfulness-based stress reduction in routine multiple sclerosis care. Facilitators to implementation included introducing a pre-course orientation session; adaptations to mindfulness-based stress reduction to accommodate comorbidity and disability and participants suggested smaller, shorter classes, shortened practices, exclusion of mindful-walking and more time with peers. Post-mindfulness-based stress reduction booster sessions may be required, and objective and subjective reports of benefit would increase clinician confidence in mindfulness-based stress reduction.
Discussion:
Multiple sclerosis patients and clinicians know little about mindfulness-based stress reduction. Mismatched expectations are a barrier to participation, as is rigid application of mindfulness-based stress reduction in the context of disability. Course adaptations in response to patient needs would facilitate uptake and utilisation. Rendering access to mindfulness-based stress reduction rapid and flexible could facilitate implementation. Embedded outcome assessment is desirable
Drug interactions may be important risk factors for methotrexate neurotoxicity, particularly in pediatric leukemia patients
Purpose: Methotrexate administration is associated with
frequent adverse neurological events during treatment for
childhood acute lymphoblastic leukemia. Here, we present
evidence to support the role of common drug interactions
and low vitamin B12 levels in potentiating methotrexate
neurotoxicity.
Methods: We review the published evidence and highlight
key potential drug interactions as well as present clinical
evidence of severe methotrexate neurotoxicity in conjunction
with nitrous oxide anesthesia and measurements of
vitamin B12 levels among pediatric leukemia patients during
therapy.
Results: We describe a very plausible mechanism for
methotrexate neurotoxicity in pediatric leukemia patients
involving reduction in methionine and consequential disruption
of myelin production. We provide evidence that a
number of commonly prescribed drugs in pediatric leukemia
management interact with the same folate biosynthetic
pathways and/or reduce functional vitamin B12 levels and
hence are likely to increase the toxicity of methotrexate in
these patients. We also present a brief case study supporting
out hypothesis that nitrous oxide contributes to methotrexate
neurotoxicity and a nutritional study, showing that
patients.
Conclusions: Use of nitrous oxide in pediatric leukemia
patients at the same time as methotrexate use should be
avoided especially as many suitable alternative anesthetic
agents exist. Clinicians should consider monitoring levels
of vitamin B12 in patients suspected of having methotrexate-
induced neurotoxic effects
Reply: Methotrexate neurotoxicity due to drug interactions: an inadequate folinic acid effect
No abstract available
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