871 research outputs found
The Fear Reduction Exercised Early (FREE) approach to low back pain: study protocol for a randomised controlled trial
This is the final version of the article. Available from BioMed Central via the DOI in this record.BACKGROUND: Low back pain (LBP) is a major health issue associated with considerable health loss and societal costs. General practitioners (GPs) play an important role in the management of LBP; however, GP care has not been shown to be the most cost-effective approach unless exercise and behavioural counselling are added to usual care. The Fear Reduction Exercised Early (FREE) approach to LBP has been developed to assist GPs to manage LBP by empowering exploration and management of psychosocial barriers to recovery and provision of evidence-based care and information. The aim of the Low Back Pain in General Practice (LBPinGP) trial is to explore whether patients with LBP who receive care from GPs trained in the FREE approach have better outcomes than those who receive usual care. METHODS/DESIGN: This is a cluster randomised controlled superiority trial comparing the FREE approach with usual care for LBP management with investigator-blinded assessment of outcomes. GPs will be recruited and then cluster randomised (in practice groups) to the intervention or control arm. Intervention arm GPs will receive training in the FREE approach, and control arm GPs will continue to practice as usual. Patients presenting to their GP with a primary complaint of LBP will be allocated on the basis of allocation of the GP they consult. We aim to recruit 60 GPs and 275 patients (assuming patients are recruited from 75% of GPs and an average of 5 patients per GP complete the study, accounting for 20% patient participant dropout). Patient participants and the trial statistician will be blind to group allocation throughout the study. Analyses will be undertaken on an intention-to-treat basis. The primary outcome will be back-related functional impairment 6 months post-initial LBP consultation (interim data at 2 weeks, 6 weeks and 3 months), measured with the Roland-Morris Disability Questionnaire. Secondary patient outcomes include pain, satisfaction, quality of life, days off from work and costs of care. Secondary GP outcomes include beliefs about pain and impairment, GP confidence, and actual and reported clinical behaviour. Health economic and process evaluations will be conducted. DISCUSSION: In the LBPinGP trial, we will investigate providing an intervention during the first interaction a person with back pain has with their GP. Because the FREE approach is used within a normal GP consultation, if effective, it may be a cost-effective means of improving LBP care. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12616000888460 . Registered on 6 July 2016.This study is funded and supported by the Accident Compensation Corporation (ACC), Wellington, New Zealand. The study funder has not been involved with study design. The study funder will not be involved with or have ultimate authority over the collection, management, analysis and interpretation of data; the writing of the report; or the decision to submit the report for publication. The funder will have the opportunity to comment on draft reports before publication. SD’s work was supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health
The impact of low erythrocyte density in human blood on the fitness and energetic reserves of the African malaria vector Anopheles gambiae
Background
Anaemia is a common health problem in the developing world. This condition is characterized by a reduction in erythrocyte density, primarily from malnutrition and/or
infectious diseases such as malaria. As red blood cells are the primary source of protein for haematophagous mosquitoes, any reduction could impede the ability of mosquito vectors to transmit malaria by influencing their fitness or that of the parasites they transmit. The aim of this study was to determine the impact of differences in the density of red blood cells in human blood on malaria vector (Anopheles gambiae sensu stricto) fitness. The hypotheses tested are that mosquito vector energetic reserves and fitness are negatively influenced by reductions in the red cell density of host human blood meals commensurate with those expected from severe anaemia.
Methods
Mosquitoes (An. gambiae s.s.) were offered blood meals of different packed cell volume(PCV) of human blood consistent with those arising from severe anaemia (15%) and normalPCV (50%). Associations between mosquito energetic reserves (lipid, glucose and glycogen)and fitness measures (reproduction and survival) and blood meal PCV were investigated.
Results
The amount of protein that malaria vectors acquired from blood feeding (indexed by
haematin excretion) was significantly reduced at low blood PCV. However, mosquitoes
feeding on blood of low PCV had the same oviposition rates as those feeding on blood of normal PCV, and showed an increase in egg production of around 15%. The long-term survival of An. gambiae s.s was reduced after feeding on low PCV blood, but PCV had no significant impact on the proportion of mosquitoes surviving through the minimal period required to develop and transmit malaria parasites (estimated as 14 days post-blood feeding). The impact of blood PCV on the energetic reserves of mosquitoes was relatively minor.
Conclusions
These results suggest that feeding on human hosts whose PCV has been depleted due to severe anaemia does not significantly reduce the fitness or transmission potential of malaria vectors, and indicates that mosquitoes may be able exploit resources for reproduction more
efficiently from blood of low rather than normal PCV
Age-related changes in global motion coherence: conflicting haemodynamic and perceptual responses
Our aim was to use both behavioural and neuroimaging data to identify indicators of perceptual decline in motion processing. We employed a global motion coherence task and functional Near Infrared Spectroscopy (fNIRS). Healthy adults (n = 72, 18-85) were recruited into the following groups: young (n = 28, mean age = 28), middle-aged (n = 22, mean age = 50), and older adults (n = 23, mean age = 70). Participants were assessed on their motion coherence thresholds at 3 different speeds using a psychophysical design. As expected, we report age group differences in motion processing as demonstrated by higher motion coherence thresholds in older adults. Crucially, we add correlational data showing that global motion perception declines linearly as a function of age. The associated fNIRS recordings provide a clear physiological correlate of global motion perception. The crux of this study lies in the robust linear correlation between age and haemodynamic response for both measures of oxygenation. We hypothesise that there is an increase in neural recruitment, necessitating an increase in metabolic need and blood flow, which presents as a higher oxygenated haemoglobin response. We report age-related changes in motion perception with poorer behavioural performance (high motion coherence thresholds) associated with an increased haemodynamic response
Static stretching of the hamstring muscle for injury prevention in football codes: a systematic review
Purpose: Hamstring injuries are common among football players. There is still disagreement regarding prevention. The aim of this review is to determine whether static stretching reduces hamstring injuries in football codes.
Methods: A systematic literature search was conducted on the online databases PubMed, PEDro, Cochrane, Web of Science, Bisp and Clinical Trial register. Study results were presented descriptively and the quality of the studies assessed were based on Cochrane’s ‘risk of bias’ tool.
Results: The review identified 35 studies, including four analysis studies. These studies show deficiencies in the quality of study designs.
Conclusion: The study protocols are varied in terms of the length of intervention and follow-up. No RCT studies are available, however, RCT studies should be conducted in the near future
The comparative osmoregulatory ability of two water beetle genera whose species span the fresh-hypersaline gradient in inland waters (Coleoptera: Dytiscidae, Hydrophilidae).
A better knowledge of the physiological basis of salinity tolerance is essential to understanding the ecology and evolutionary history of organisms that have colonized inland saline waters. Coleoptera are amongst the most diverse macroinvertebrates in inland waters, including saline habitats; however, the osmoregulatory strategies they employ to deal with osmotic stress remain unexplored. Survival and haemolymph osmotic concentration at different salinities were examined in adults of eight aquatic beetle species which inhabit different parts of the fresh-hypersaline gradient. Studied species belong to two unrelated genera which have invaded saline waters independently from freshwater ancestors; Nebrioporus (Dytiscidae) and Enochrus (Hydrophilidae). Their osmoregulatory strategy (osmoconformity or osmoregulation) was identified and osmotic capacity (the osmotic gradient between the animal's haemolymph and the external medium) was compared between species pairs co-habiting similar salinities in nature. We show that osmoregulatory capacity, rather than osmoconformity, has evolved independently in these different lineages. All species hyperegulated their haemolymph osmotic concentration in diluted waters; those living in fresh or low-salinity waters were unable to hyporegulate and survive in hyperosmotic media (> 340 mosmol kg(-1)). In contrast, the species which inhabit the hypo-hypersaline habitats were effective hyporegulators, maintaining their haemolymph osmolality within narrow limits (ca. 300 mosmol kg(-1)) across a wide range of external concentrations. The hypersaline species N. ceresyi and E. jesusarribasi tolerated conductivities up to 140 and 180 mS cm(-1), respectively, and maintained osmotic gradients over 3500 mosmol kg(-1), comparable to those of the most effective insect osmoregulators known to date. Syntopic species of both genera showed similar osmotic capacities and in general, osmotic responses correlated well with upper salinity levels occupied by individual species in nature. Therefore, osmoregulatory capacity may mediate habitat segregation amongst congeners across the salinity gradient
The effect of intra-articular botulinum toxin A on substance P, prostaglandin E-2, and tumor necrosis factor alpha in the canine osteoarthritic joint
Background: Recently, intra-articular botulinum toxin A (IA BoNT A) has been shown to reduce joint pain in osteoarthritic dogs. Similar results have been reported in human patients with arthritis. However, the mechanism of the antinociceptive action of IA BoNT A is currently not known. The aim of this study was to explore this mechanism of action by investigating the effect of IA BoNT A on synovial fluid (SF) and serum substance P (SP), prostaglandin E-2 (PGE(2)), and tumor necrosis factor alpha (TNF-alpha) in osteoarthritic dogs. Additionally, the aim was to compare SF SP and PGE(2) between osteoarthritic and non-osteoarthritic joints, and investigate associations between SP, PGE(2), osteoarthritic pain, and the signalment of dogs. Thirty-five dogs with chronic naturally occurring osteoarthritis and 13 non-osteoarthritic control dogs were included in the study. Osteoarthritic dogs received either IA BoNT A (n = 19) or IA placebo (n = 16). Serum and SF samples were collected and osteoarthritic pain was evaluated before (baseline) and 2 and 8 weeks after treatment. Osteoarthritic pain was assessed with force platform, Helsinki Chronic Pain Index, and joint palpation. Synovial fluid samples were obtained from control dogs after euthanasia. The change from baseline in SP and PGE(2) concentration was compared between the IA BoNT A and placebo groups. The synovial fluid SP and PGE(2) concentration was compared between osteoarthritic and control joints. Associations between SP, PGE(2), osteoarthritic pain, and the signalment of dogs were evaluated. Results: There was no significant change from baseline in SP or PGE(2) after IA BoNT A. Synovial fluid PGE(2) was significantly higher in osteoarthritic compared to control joints. Synovial fluid PGE(2) correlated with osteoarthritic pain. No associations were found between SP or PGE2 and the signalment of dogs. The concentration of TNF-alpha remained under the detection limit of the assay in all samples. Conclusions: The results suggest that the antinociceptive effect of IA BoNT A in the joint might not be related to the inhibition of SP nor PGE(2). Synovial fluid PGE(2,) but not SP, could be a marker for chronic osteoarthritis and pain in dogs.Peer reviewe
A logic-based representation and tree-based visualization method for building regulatory requirements
Structural decoding of netrin-4 reveals a regulatory function towards mature basement membranes
Netrins, a family of laminin-related molecules, have been proposed to act as guidance cues either during nervous system development or the establishment of the vascular system. This was clearly demonstrated for netrin-1 via its interaction with the receptors DCC and UNC5s. However, mainly based on shared homologies with netrin-1, netrin-4 was also proposed to play a role in neuronal outgrowth and developmental/pathological angiogenesis via interac- tions with netrin-1 receptors. Here, we present the high-resolution structure of netrin-4, which shows unique features in comparison with netrin-1, and show that it does not bind directly to any of the known netrin-1 receptors. We show that netrin-4 disrupts laminin networks and basement membranes (BMs) through high-affinity binding to the laminin g1 chain. We hypothesize that this laminin-related function is essential for the previously described effects on axon growth promotion and angiogenesis. Our study unveils netrin-4 as a non-enzymatic extracellular matrix protein actively disrupting pre-existing BMs
Effect of ketoconazole on the pharmacokinetics of axitinib in healthy volunteers
Objective Axitinib (AG-013736), an oral, potent, and selective inhibitor of vascular endothelial growth factor receptors 1, 2, and 3, is metabolized primarily by cytochrome P450 (CYP) 3A with minor contributions from CYP1A2, CYP2C19, and glucuronidation. Co-administration with CYP inhibitors may increase systemic exposure to axitinib and alter its safety profile. This study evaluated changes in axitinib plasma pharmacokinetic parameters and assessed safety and tolerability in healthy subjects, following axitinib co-administration with the potent CYP3A inhibitor ketoconazole. Methods In this randomized, single-blind, two-way crossover study, 32 healthy volunteers received placebo, followed by a single 5-mg oral dose of axitinib, administered either alone or on the fourth day of dosing with oral ketoconazole (400 mg/day for 7 days). Results Axitinib exposure was significantly increased in the presence of ketoconazole, with a geometric mean ratio for area under the plasma concentration–time curve from time zero to infinity of 2.06 (90% confidence interval [CI]: 1.84–2.30) and a geometric mean ratio for maximum plasma concentration (Cmax) of 1.50 (90% CI: 1.33–1.70). For axitinib alone or with ketoconazole, Cmax occurred 1.5 and 2.0 h after dosing, respectively. Adverse events were predominantly mild; the most commonly reported treatment-related adverse events were headache and nausea. Conclusions Axitinib plasma exposures and peak concentrations were increased following concurrent administration of axitinib and ketoconazole in healthy volunteers. Axitinib alone and in combination with ketoconazole was well tolerated. These findings provide an upper exposure for expected axitinib plasma concentrations in the presence of potent metabolic inhibition
Investigation of the obscuring circumnuclear torus in the active galaxy Mrk231
Here we report on observations of powerful hydroxyl (OH) line emissions that
trace the obscuring material within the circumnuclear environment of the galaxy
Markarian 231. The hydroxyl (mega)-maser emission shows the characteristics of
a rotating, dusty, molecular torus (or thick disk) located between 30 and 100
pc from the central engine. We now have a clear view of the physical
conditions, the kinematics and the spatial structure of this material on
intermediate size scales, confirming the main tenets of unification models.Comment: 10 pages, including 3 Figures, published in Nature Vol 421 2003; the
published pdf--file and higher quality images are available at
http://www.astro.rug.nl/~hrkloeck/np/pubmrk231.htm
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