141 research outputs found
A review of standard pharmacological therapy for adult asthma - Steps 1 to 5
The aim of pharmacological therapy for asthma is to improve symptoms and lung function and minimise the risk of asthma attacks. The intensity of treatment is based on the level of asthma control and the potential risk of future deterioration. In the British asthma guidelines, treatments are divided into Step One to Five, with each Step signifying a need for an increase in therapy in response to symptoms or to prevent exacerbations. Treatments comprise of inhaled or systemic medications. Inhaled therapy includes short-acting and long-acting medication to improve symptoms and inhaled corticosteroids which reduce airway inflammation. Systemic treatments include medications which act on specific biological pathways, such as the leukotriene or IgE pathways, or systemic corticosteroids. In choosing a particular therapy, treatment benefits are balanced by the potential risks of medication-related adverse effects. This review will provide a practical guide to the key pharmacological therapies for adult asthma at Steps One to Five based on British guidelines and consider future options for new treatments
Strain-controlled criticality governs the nonlinear mechanics of fibre networks
Disordered fibrous networks are ubiquitous in nature as major structural
components of living cells and tissues. The mechanical stability of networks
generally depends on the degree of connectivity: only when the average number
of connections between nodes exceeds the isostatic threshold are networks
stable (Maxwell, J. C., Philosophical Magazine 27, 294 (1864)). Upon increasing
the connectivity through this point, such networks undergo a mechanical phase
transition from a floppy to a rigid phase. However, even sub-isostatic networks
become rigid when subjected to sufficiently large deformations. To study this
strain-controlled transition, we perform a combination of computational
modeling of fibre networks and experiments on networks of type I collagen
fibers, which are crucial for the integrity of biological tissues. We show
theoretically that the development of rigidity is characterized by a
strain-controlled continuous phase transition with signatures of criticality.
Our experiments demonstrate mechanical properties consistent with our model,
including the predicted critical exponents. We show that the nonlinear
mechanics of collagen networks can be quantitatively captured by the
predictions of scaling theory for the strain-controlled critical behavior over
a wide range of network concentrations and strains up to failure of the
material
A randomized open-label trial on the use of budesonide/formoterol (Symbicort®) as an alternative reliever medication for mild to moderate asthmatic attacks
BACKGROUND
Conventionally, a nebulized short-acting β-2 agonist like salbutamol is often used as the reliever in acute exacerbations of asthma. However, recent worldwide respiratory outbreaks discourage routine use of nebulization. Previous studies have shown that combined budesonide/formoterol (Symbicort®, AstraZeneca) is effective as both a maintenance and reliever anti-asthmatic medication.
METHODS
We performed a randomized, open-label study from March until August 2011 to compare the bronchodilatory effects of Symbicort® vs. nebulized salbutamol in acute exacerbation of mild to moderate asthmatic attack in an emergency department. Initial objective parameters measured include the oxygen saturation, peak expiratory flow rate (PEFR) and respiratory rate. During clinical reassessment, subjective parameters [i.e., Visual Analog Scale (VAS) and 5-point Likert scale of breathlessness] and the second reading of the objective parameters were measured. For the 5-point Likert scale, the patients were asked to describe their symptom relief as 1, much worse; 2, a little worse; 3, no change; 4, a little better; 5, much better.
RESULTS
Out of the total of 32 patients enrolled, 17 patients (53%) were randomized to receive nebulized salbutamol and 15 (47%) to receive Symbicort®. For both treatment arms, by using paired t- and Wilcoxon signed rank tests, it was shown that there were statistically significant improvements in oxygen saturation, PEFR and respiratory rate within the individual treatment groups (pre- vs. post-treatment). Comparing the effects of Symbicort® vs. nebulized salbutamol, the average improvement of oxygen saturation was 1% in both treatment arms (p = 0.464), PEFR 78.67 l/min vs. 89.41 l/min, respectively (p = 0.507), and respiratory rate 2/min vs. 2/min (p = 0.890). For subjective evaluation, all patients reported improvement in the VAS (average 2.45 cm vs. 2.20 cm), respectively (p = 0.765). All patients in both treatment arms reported either "a little better" or "much better" on the 5-point Likert scale, with none reporting "no change" or getting worse.
CONCLUSION
This study suggests that there is no statistical difference between using Symbicort® vs. nebulized salbutamol as the reliever for the first 15 min post-intervention
Parity-Violating Electron Scattering from 4He and the Strange Electric Form Factor of the Nucleon
We have measured the parity-violating electroweak asymmetry in the elastic
scattering of polarized electrons from ^4He at an average scattering angle
= 5.7 degrees and a four-momentum transfer Q^2 = 0.091 GeV^2. From
these data, for the first time, the strange electric form factor of the nucleon
G^s_E can be isolated. The measured asymmetry of A_PV = (6.72 +/- 0.84 (stat)
+/- 0.21 (syst) parts per million yields a value of G^s_E = -0.038 +/- 0.042
(stat) +/- 0.010 (syst), consistent with zero
Wet Granular Materials
Most studies on granular physics have focused on dry granular media, with no
liquids between the grains. However, in geology and many real world
applications (e.g., food processing, pharmaceuticals, ceramics, civil
engineering, constructions, and many industrial applications), liquid is
present between the grains. This produces inter-grain cohesion and drastically
modifies the mechanical properties of the granular media (e.g., the surface
angle can be larger than 90 degrees). Here we present a review of the
mechanical properties of wet granular media, with particular emphasis on the
effect of cohesion. We also list several open problems that might motivate
future studies in this exciting but mostly unexplored field.Comment: review article, accepted for publication in Advances in Physics;
tex-style change
Developing evidence-based clinical practice guidelines in hospitals in Australia, Indonesia, Malaysia, the Philippines and Thailand: values, requirements and barriers
<p>Abstract</p> <p>Background</p> <p>Evidence-based clinical practice guidelines support clinical decision-making by making recommendations to guide clinical practice. These recommendations are developed by integrating the expertise of a multidisciplinary group of clinicians with the perspectives of consumers and the best available research evidence. However studies have raised concerns about the quality of guideline development, and particularly the link between research and recommendations. The reasons why guideline developers are not following the established development methods are not clear.</p> <p>We aimed to explore the barriers to developing evidence-based guidelines in eleven hospitals in Australia, Indonesia, Malaysia, the Philippines and Thailand, so as to better understand how evidence-based guideline development could be facilitated in these settings. The research aimed to identify the value clinicians place on guidelines, what clinicians want in guidelines developed in hospital settings and what factors limit rigorous evidence-based guideline development in these settings.</p> <p>Methods</p> <p>Semi-structured, face-to-face interviews were undertaken with senior and junior healthcare providers (nurses, midwives, doctors, allied health) from the maternal and neonatal services of the eleven participating hospitals. Interviews were audio-recorded, transcribed and a thematic analysis undertaken.</p> <p>Results</p> <p>Ninety-three individual, 25 pair and eleven group interviews were conducted. Participants were clear that they want guidelines that are based on evidence and updated regularly. They were also clear that there are major barriers to this. Most of the barriers were shared across countries, and included lack of time, lack of skills in finding, appraising and interpreting evidence, lack of access to relevant evidence and difficulty arranging meetings and achieving consensus.</p> <p>Barriers that were primarily identified in Australian hospitals include cumbersome organisational processes and a feeling that guidelines are being developed for bureaucratic ends. Barriers that were primarily identified in South East Asian hospitals include difficulty accessing evidence due to limited resources available for computers, internet and journal subscriptions and limited skills in computing and English.</p> <p>Conclusions</p> <p>The clinicians in these eleven very different hospitals want evidence-based guidelines. However they are frustrated by guideline development processes that are enormously time, skill and resource intensive. They feel strongly that "there's got to be a better way".</p> <p>The fact that the great majority of the identified barriers were shared across settings may provide an opportunity to develop a more pragmatic way of developing guidelines that can be applied in many contexts.</p
New Measurement of Parity Violation in Elastic Electron-Proton Scattering and Implications for Strange Form Factors
We have measured the parity-violating electroweak asymmetry in the elastic
scattering of polarized electrons from the proton. The result is A = -15.05 +-
0.98(stat) +- 0.56(syst) ppm at the kinematic point theta_lab = 12.3 degrees
and Q^2 = 0.477 (GeV/c)^2. The measurement implies that the value for the
strange form factor (G_E^s + 0.392 G_M^s) = 0.025 +- 0.020 +- 0.014, where the
first error is experimental and the second arises from the uncertainties in
electromagnetic form factors. This measurement is the first fixed-target parity
violation experiment that used either a `strained' GaAs photocathode to produce
highly polarized electrons or a Compton polarimeter to continuously monitor the
electron beam polarization.Comment: 8 pages, 4 figures, Tex, elsart.cls; revised version as accepted for
Phys. Lett.
Quantitative imaging of concentrated suspensions under flow
We review recent advances in imaging the flow of concentrated suspensions,
focussing on the use of confocal microscopy to obtain time-resolved information
on the single-particle level in these systems. After motivating the need for
quantitative (confocal) imaging in suspension rheology, we briefly describe the
particles, sample environments, microscopy tools and analysis algorithms needed
to perform this kind of experiments. The second part of the review focusses on
microscopic aspects of the flow of concentrated model hard-sphere-like
suspensions, and the relation to non-linear rheological phenomena such as
yielding, shear localization, wall slip and shear-induced ordering. Both
Brownian and non-Brownian systems will be described. We show how quantitative
imaging can improve our understanding of the connection between microscopic
dynamics and bulk flow.Comment: Review on imaging hard-sphere suspensions, incl summary of
methodology. Submitted for special volume 'High Solid Dispersions' ed. M.
Cloitre, Vol. xx of 'Advances and Polymer Science' (Springer, Berlin, 2009);
22 pages, 16 fig
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