1,502 research outputs found
Bremsstrahlung neutrinos from electron-electron scattering in a relativistic degenerate electron plasma
We present a calculation of neutrino pair bremsstrahlung due to
electron-electron scattering in a relativistic degenerate plasma of electrons.
Proper treatment of the in-medium photon propagator, i.e., inclusion of Debye
screening of the longitudinal part and Landau damping of the transverse part,
leads to a neutrino emissivity which is several orders of magnitude larger than
when Debye screening is imposed for the tranverse part. Our results show that
this in-medium process can compete with other sources of neutrino radiation and
can, in some cases, even be the dominant neutrino emission mechanism. We also
discuss the natural extension to quark-quark bremsstrahlung in gapped and
ungapped quark matter.Comment: 15 pages, 7 figure
Electron-Neutrino Bremsstrahlung in Electro-Weak Theory
The electron-neutrino bremsstrahlung process has been considered in the
framework of electro-weak theory. The scattering cross section has been
calculated in the center of mass frame and approximated to extreme relativistic
as well as non-relativistic case. The rate of energy-loss via this type of
bremsstrahlung process has been obtained both in non-degenerate and degenerate
region. The effect of this electron-neutrino bremsstrahlung process in
different ranges of temperature and density characterizing the late stages of
stellar evolution has been discussed. It is found from our study that this
bremsstrahlung process is highly important in the non-degenerate region,
although it might have some significant effect in the extreme relativistic
degenerate region.Comment: 18 pages including 4 figures and 1 table; Published in J. Phys
Combining triple therapy and pulmonary rehabilitation in patients with advanced COPD: a pilot study.
BACKGROUND: The synergistic interactions between pharmacotherapy and pulmonary rehabilitation has been provided, but it remains to be established whether this may also apply to more severe patients.
OBJECTIVES: We have examined whether tiotropium enhances the effects of exercise training in patients with advanced COPD (FEV(1)</=60% predicted, hypoxemia at rest corrected with oxygen supplementation, and limitations of physical activity).
METHODS: We enrolled 22 patients that were randomised to tiotropium 18mug or placebo inhalation capsules taken once daily. Both groups (11 patients in each group) underwent an in patient pulmonary rehabilitation program and were under regular treatment with salmeterol/fluticasone twice daily. Each rehabilitation session was held 5 days per week (3h/day) for a total of 4 weeks.
RESULTS: Compared to placebo, tiotropium had larger impact on pulmonary function (FEV(1)+0.164L, FVC +0.112L, RV -0.544L after tiotropium, FEV(1)+0.084L, FVC -0.039L, RV -0.036L after placebo). The addition of tiotropium allowed a longer distance walked in 6min (82.3m vs. 67.7m after placebo) and reduced dyspnoea (Borg score) (-0.4 vs. +0.18 after placebo) when compared with baseline (pre pulmonary rehabilitation program). The changes in SGRQ from baseline to the end of treatment were: total score -28.3U, activity -27.8U, impact -14.5U, and symptoms -33.4U in the placebo group; and total score -19.1U, activity -18.9U, impact -16.4U, and symptoms -33.8U in the tiotropium group.
CONCLUSIONS: Our study clearly indicates that there is an advantage in combining pulmonary rehabilitation with an aggressive drug therapy in more severe patient
Combining triple therapy and pulmonary rehabilitation in patients with advanced COPD: a pilot study.
BACKGROUND: The synergistic interactions between pharmacotherapy and pulmonary rehabilitation has been provided, but it remains to be established whether this may also apply to more severe patients.
OBJECTIVES: We have examined whether tiotropium enhances the effects of exercise training in patients with advanced COPD (FEV(1)</=60% predicted, hypoxemia at rest corrected with oxygen supplementation, and limitations of physical activity).
METHODS: We enrolled 22 patients that were randomised to tiotropium 18mug or placebo inhalation capsules taken once daily. Both groups (11 patients in each group) underwent an in patient pulmonary rehabilitation program and were under regular treatment with salmeterol/fluticasone twice daily. Each rehabilitation session was held 5 days per week (3h/day) for a total of 4 weeks.
RESULTS: Compared to placebo, tiotropium had larger impact on pulmonary function (FEV(1)+0.164L, FVC +0.112L, RV -0.544L after tiotropium, FEV(1)+0.084L, FVC -0.039L, RV -0.036L after placebo). The addition of tiotropium allowed a longer distance walked in 6min (82.3m vs. 67.7m after placebo) and reduced dyspnoea (Borg score) (-0.4 vs. +0.18 after placebo) when compared with baseline (pre pulmonary rehabilitation program). The changes in SGRQ from baseline to the end of treatment were: total score -28.3U, activity -27.8U, impact -14.5U, and symptoms -33.4U in the placebo group; and total score -19.1U, activity -18.9U, impact -16.4U, and symptoms -33.8U in the tiotropium group.
CONCLUSIONS: Our study clearly indicates that there is an advantage in combining pulmonary rehabilitation with an aggressive drug therapy in more severe patient
Pharmacological management of COVID-19 patients with ARDS (CARDS): A narrative review
Coronavirus disease 2019 (COVID-19) is highly infectious. It has been highlighted that if not expertly and individually managed with consideration of the vasocentric features, a COVID-19 patient with an acute respiratory distress syndrome (CARDS) may eventually develop multiorgan failure. Unfortunately, there is still no definite drug for CARDS that is capable of reducing either short-term or long-term mortality and no specific treatments for COVID-19 exist right now. In this narrative review, based on a selective literature search in EMBASE, MEDLINE, Scopus, The Cochrane Library, Web of Science, and Google Scholar and ClinicalTrials.gov, we have examined the emerging evidence on the possible treatment of CARDS. Although numerous pharmacologic therapies to improve clinical outcomes in CARDS have been studied also in clinical trials, none have shown efficacy and there is great uncertainty about their effectiveness. There is still no recommendation for the therapeutic use of any specific agent to treat CARDS because no drugs are validated to have significant efficacy in clinical treatment of COVID-19 patients in large-scale trials. However, there exist a number of drugs that may be useful at least in some patients. The real challenge now is to link the right patient to the right treatment
Salmeterol and formoterol in partially reversible severe chronic obstructive pulmonary disease: a dose-response study
AbstractWhen testing the response to β2-agonist drugs in severe chronic obstructive pulmonary disease (COPD), a dose-response assessment should be undertaken. This study compares the time course of inhaled salmeterol (25, 50 and 75 μg) and formoterol (12, 24 and 36 μg) at different doses in a group of 12 patients with partially reversible, but severe COPD (FEV1 of 12–32% of predicted values after β2-agonist drugs had been withheld for 24 h). All doses of salmeterol and formoterol induced a significant (P<0·01) spirometric improvement over the 12-h monitoring period, when compared to the spirometric improvement after placebo, but while formoterol induced a dose-dependent increase of the FVC, FEV1 and FEF50, this was not the case for salmeterol. In fact, 75 μg salmeterol did not produce a further improvement of these parameters. Mean peak bronchodilation, expressed as the increase in FEV1 over baseline values, occurred 2 h after inhalation of the three doses of salmeterol, and 1 h after inhalation of the three doses of formoterol. A comparison of 50 μg salmeterol with 12 μg or 24 μg formoterol (clinically recommended doses), showed that improvement of FEV1 after salmeterol was statistically (P<0·05) higher than that after the two doses of formoterol, although the mean peak bronchodilations were similar. This was because salmeterol has a longer duration of action than formoterol. These data demonstrate that salmeterol is equally effective as, but longer-acting than, formoterol at clinically recommended doses in patients suffering from COPD, with severe airway obstruction. Moreover, these data suggest that 50 μg is the best dosage for salmeterol in these patients
Cervical spine injuries: A whole-body musculoskeletal model for the analysis of spinal loading
This is the final version of the article. Available from Public Library of Science via the DOI in this record.Cervical spine trauma from sport or traffic collisions can have devastating consequences for individuals and a high societal cost. The precise mechanisms of such injuries are still unknown as investigation is hampered by the difficulty in experimentally replicating the conditions under which these injuries occur. We harness the benefits of computer simulation to report on the creation and validation of i) a generic musculoskeletal model (MASI) for the analyses of cervical spine loading in healthy subjects, and ii) a population-specific version of the model (Rugby Model), for investigating cervical spine injury mechanisms during rugby activities. The musculoskeletal models were created in OpenSim, and validated against in vivo data of a healthy subject and a rugby player performing neck and upper limb movements. The novel aspects of the Rugby Model comprise i) population-specific inertial properties and muscle parameters representing rugby forward players, and ii) a custom scapula-clavicular joint that allows the application of multiple external loads. We confirm the utility of the developed generic and population-specific models via verification steps and validation of kinematics, joint moments and neuromuscular activations during rugby scrummaging and neck functional movements, which achieve results comparable with in vivoand in vitrodata. The Rugby Model was validated and used for the first time to provide insight into anatomical loading and cervical spine injury mechanisms related to rugby, whilst the MASI introduces a new computational tool to allow investigation of spinal injuries arising from other sporting activities, transport, and ergonomic applications. The models used in this study are freely available at simtk.org and allow to integrate in silico analyses with experimental approaches in injury prevention.Funding: This project is funded by the Rugby Football Union (RFU) Injured Players Foundation. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Effect of formoterol/budesonide combination on arterial blood gases in patients with acute exacerbation of COPD
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Rapid onset of bronchodilation with formoterol/beclomethasone Modulite and formoterol/budesonide Turbuhaler as compared to formoterol alone in patients with COPD
In the present study, we examined whether there is a difference in the onset of bronchodilatation between formoterol/beclomethasone 12/200 μg Modulite and formoterol/budesonide 9/320 μg Turbuhaler in patients with COPD. We enrolled 28 patients with stable COPD. Both formoterol/beclomethasone and formoterol/budesonide elicited a larger mean FEV1–AUC0−15min than formoterol alone, whereas there was no significant difference between their FEV1–AUC0−15min. Also the change in FEV1 15 min after inhalation of formoterol/beclomethasone combination or formoterol/budesonide combination was greater than that induced by formoterol alone. This study confirms the rapid effect of the inhaled corticosteroid component when combined with formoterol and indicates that the onset of bronchodilation of formoterol/beclomethasone Modulite and formoterol/budesonide Turbuhaler are similar and greater than formoterol alone in patients with COPD
Mutational analysis of BCORL1 in the leukemic transformation of chronic myeloproliferative neoplasms.
BCORL1 mutations do not seem to be commonly associated with leukemic transformation of MPN, further substantiating the different molecular profile compared with denovo leukemias. Although the small number of cases does not allow us to exclude that BCORL1 mutations can be found also in post-MPN AML, their occurrence is, at least, very infrequent and their detection does not appear to deserve clinical relevance
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