1,308 research outputs found

    Patients' treatment beliefs in low back pain: development and validation of a questionnaire in primary care

    Get PDF
    Choosing the most appropriate treatment for individual patients with low back pain (LBP) can be challenging, and clinical guidelines recommend taking into account patients' preferences. However, no tools exist to assess or compare patients' views about LBP treatments. We report the development and validation of the LBP Treatment Beliefs Questionnaire (LBP-TBQ) for use across different treatments in clinical practice and research. Using qualitative data we developed a pool of items assessing perceived credibility, effectiveness, concerns about and individual 'fit' of specific treatments. These items were included in a survey completed by 429 primary care patients with LBP, of whom 115 completed it again 1 to 2 weeks later. We performed psychometric analyses using non-parametric item response theory and classical test theory. The four subscales of the resulting 16-item LBP-TBQ showed good homogeneity (H=.46-.76), internal consistency (α =.73-.94), and stability (r=.63-.83), confirmed most convergent and discriminant validity hypotheses, and had acceptable structural validity for four guideline-recommended treatments: pain medication, exercise, manual therapy and acupuncture. Participants with stronger positive treatment beliefs were more likely to rank that treatment as their first choice, indicating good criterion validity (t values=3.11-9.80, all p<.01, except pain medication effectiveness beliefs, t(339)=1.35; p=.18). A short 4-item version also displayed good homogeneity (H=.43-.66), internal consistency (α=.70-.86), and stability (r=.82-.85), and was significantly related to treatment choice (t values=4.33-9.25, all p<.01). The LBP-TBQ can be used to assess treatment beliefs in primary care patients with LBP and to investigate the effects of treatment beliefs on treatment uptake and adherence.This is an open access article distributed under the terms of the Creative Commons Attribution-Noncommercial No Derivatives 3.0 License, which permits downloading and sharing the work provided it is properly cited. The work cannot be changed in any way or used commercially

    The clinical course of acute otitis media in high-risk Australian Aboriginal children: a longitudinal study

    Get PDF
    BACKGROUND: It is unclear why some children with acute otitis media (AOM) have poor outcomes. Our aim was to describe the clinical course of AOM and the associated bacterial nasopharyngeal colonisation in a high-risk population of Australian Aboriginal children. METHODS: We examined Aboriginal children younger than eight years who had a clinical diagnosis of AOM. Pneumatic otoscopy and video-otoscopy of the tympanic membrane (TM) and tympanometry was done every weekday if possible. We followed children for either two weeks (AOM without perforation), or three weeks (AOM with perforation), or for longer periods if the infection persisted. Nasopharyngeal swabs were taken at study entry and then weekly. RESULTS: We enrolled 31 children and conducted a total of 219 assessments. Most children had bulging of the TM or recent middle ear discharge at diagnosis. Persistent signs of suppurative OM (without ear pain) were present in most children 7 days (23/30, 77%), and 14 days (20/26, 77%) later. Episodes of AOM did not usually have a sudden onset or short duration. Six of the 14 children with fresh discharge in their ear canal had an intact or functionally intact TM. Perforation size generally remained very small (<2% of the TM). Healing followed by re-perforation was common. Ninety-three nasophyngeal swabs were taken. Most swabs cultured Streptococcus pneumoniae (82%), Haemophilus influenzae (71%), and Moraxella catarrhalis (95%); 63% of swabs cultured all three pathogens. CONCLUSION: In this high-risk population, AOM was generally painless and persistent. These infections were associated with persistent bacterial colonisation of the nasopharynx and any benefits of antibiotics were modest at best. Systematic follow up with careful examination and review of treatment are required and clinical resolution cannot be assumed

    Comparison of geometric morphometric outline methods in the discrimination of age-related differences in feather shape

    Get PDF
    BACKGROUND: Geometric morphometric methods of capturing information about curves or outlines of organismal structures may be used in conjunction with canonical variates analysis (CVA) to assign specimens to groups or populations based on their shapes. This methodological paper examines approaches to optimizing the classification of specimens based on their outlines. This study examines the performance of four approaches to the mathematical representation of outlines and two different approaches to curve measurement as applied to a collection of feather outlines. A new approach to the dimension reduction necessary to carry out a CVA on this type of outline data with modest sample sizes is also presented, and its performance is compared to two other approaches to dimension reduction. RESULTS: Two semi-landmark-based methods, bending energy alignment and perpendicular projection, are shown to produce roughly equal rates of classification, as do elliptical Fourier methods and the extended eigenshape method of outline measurement. Rates of classification were not highly dependent on the number of points used to represent a curve or the manner in which those points were acquired. The new approach to dimensionality reduction, which utilizes a variable number of principal component (PC) axes, produced higher cross-validation assignment rates than either the standard approach of using a fixed number of PC axes or a partial least squares method. CONCLUSION: Classification of specimens based on feather shape was not highly dependent of the details of the method used to capture shape information. The choice of dimensionality reduction approach was more of a factor, and the cross validation rate of assignment may be optimized using the variable number of PC axes method presented herein

    Unintended consequences of patient online access to health records: a qualitative study in UK primary care

    Get PDF
    Background: Health systems around the world are seeking to harness digital tools to promote patient autonomy and increase the efficiency of care. One example of this policy in England is online patient access to full medical records in primary care. Since April 2019, all NHS England patients have had the right to access their full medical record prospectively, and full record access has been the “default position” since April 2020. / Aim: To identify and understand the unintended consequences of online patient access their medical record. / Design and Setting: Qualitative interview study in 10 general practices in South West and North West England. / Method: Semi-structured individual interviews with 13 patients and 16 general practice staff with experience of patient online access to health records. / Results: Online access generated unintended consequences that negatively impacted patients’ understanding of their health care, for example patients discovering surprising information or information that was difficult to interpret. Online access impacted GPs’ documentation practices, such as when GPs pre-emptively attempted to minimise potential misunderstandings to aid patient understanding of their health care, in other cases, negatively impacting the quality of the records and patient safety when GPs avoided documenting their speculations or concerns. Contrary to assumptions that practice workload would be reduced, online access introduced extra work, such as managing and monitoring access and taking measures to prevent possible harm to patients. / Conclusion: The unintended consequences described by both staff and patients show that to achieve the intended consequences set out in NHS policy additional work is necessary to prepare records for sharing and prepare patients about what to expect. It is crucial that practices are adequately supported and resourced to manage the unintended consequences of online access now that it is the default position

    The phase diagram of Yang-Mills theory with a compact extra dimension

    Get PDF
    We present a non-perturbative study of the phase diagram of SU(2) Yang-Mills theory in a five-dimensional spacetime with a compact extra dimension. The non-renormalizable theory is regularized on an anisotropic lattice and investigated through numerical simulations in a regime characterized by a hierarchy between the scale of low-energy physics, the inverse compactification radius, and the cutoff scale. We map out the structure of the phase diagram and the pattern of lines corresponding to fixed values of the ratio between the mass of the fifth component of the gauge field and the non-perturbative mass gap of the four-dimensional modes. We discuss different limits of the model, and comment on the implications of our findings.Comment: 17 pages, 9 figure

    Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

    Get PDF
    BACKGROUND: Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production – due to competition with neuronal NO-synthase (nNOS) for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR), leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity. In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation. METHODS: Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 – 16 Hz)-induced relaxation was measured in tracheal open-ring preparations precontracted to 30% with histamine in the presence of 1 μM atropine and 3 μM indomethacin. The contribution of NO to EFS-induced relaxation was assessed by the nonselective NOS inhibitor N(ω)-nitro-L-arginine (L-NNA, 100 μM), while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor N(ω)-hydroxy-nor-L-arginine (nor-NOHA, 10 μM). Furthermore, the role of substrate availability to nNOS was measured in the presence of exogenous L-arginine (5.0 mM). RESULTS: At 6 h after ovalbumin-challenge (after the EAR), EFS-induced relaxation (ranging from 3.2 ± 1.1% at 0.5 Hz to 58.5 ± 2.2% at 16 Hz) was significantly decreased compared to unchallenged controls (7.1 ± 0.8% to 75.8 ± 0.7%; P < 0.05 all). In contrast to unchallenged controls, the NOS inhibitor L-NNA did not affect EFS-induced relaxation after allergen challenge, indicating that NO deficiency underlies the impaired relaxation. Remarkably, the specific arginase inhibitor nor-NOHA normalized the impaired relaxation to unchallenged control (P < 0.05 all), which effect was inhibited by L-NNA (P < 0.01 all). Moreover, the effect of nor-NOHA was mimicked by exogenous L-arginine. CONCLUSION: The results clearly demonstrate that increased arginase activity after the allergen-induced EAR contributes to a deficiency of iNANC nerve-derived NO and decreased airway smooth muscle relaxation, presumably via increased substrate competition with nNOS

    Reference values for exhaled nitric oxide (reveno) study

    Get PDF
    BACKGROUND: Despite the widespread use of fractional exhaled nitric oxide (FE(NO)) as a biomarker of airways inflammation, there are no published papers describing normal FE(NO )values in a large group of healthy adults. OBJECTIVE: The aim of this study was to establish adult FE(NO )reference values according to the international guidelines. METHODS: FE(NO )was measured in 204 healthy, non-smoking adults with normal spirometry values using the on-line single-breath technique, and the results were analysed chemiluminescently. RESULTS: The main result of the study was the significant difference in FE(NO )values between men and women, thus indicating that gender-based reference FE(NO )values are necessary. The FE(NO )levels obtained at expiratory flows of 50 ml/s ranged from 2.6 to 28.8 ppb in men, and from 1.6 to 21.5 ppb in women. CONCLUSION: We propose reference FE(NO )values for healthy adult men and women that could be used for clinical and research purposes

    Arginase attenuates inhibitory nonadrenergic noncholinergic nerve-induced nitric oxide generation and airway smooth muscle relaxation

    Get PDF
    BACKGROUND: Recent evidence suggests that endogenous arginase activity potentiates airway responsiveness to methacholine by attenuation of agonist-induced nitric oxide (NO) production, presumably by competition with epithelial constitutive NO synthase for the common substrate, L-arginine. Using guinea pig tracheal open-ring preparations, we now investigated the involvement of arginase in the modulation of neuronal nitric oxide synthase (nNOS)-mediated relaxation induced by inhibitory nonadrenergic noncholinergic (iNANC) nerve stimulation. METHODS: Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 – 16 Hz)-induced relaxation was measured in tracheal preparations precontracted to 30% with histamine, in the presence of 1 μM atropine and 3 μM indomethacin. The contribution of NO to the EFS-induced relaxation was assessed by the nonselective NOS inhibitor L-NNA (0.1 mM), while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor nor-NOHA (10 μM). Furthermore, the role of substrate availability to nNOS in EFS-induced relaxation was measured in the presence of various concentrations of exogenous L-arginine. RESULTS: EFS induced a frequency-dependent relaxation, ranging from 6.6 ± 0.8% at 0.5 Hz to 74.6 ± 1.2% at 16 Hz, which was inhibited with the NOS inhibitor L-NNA by 78.0 ± 10.5% at 0.5 Hz to 26.7 ± 7.7% at 8 Hz (P < 0.01 all). In contrast, the arginase inhibitor nor-NOHA increased EFS-induced relaxation by 3.3 ± 1.2-fold at 0.5 Hz to 1.2 ± 0.1-fold at 4 Hz (P < 0.05 all), which was reversed by L-NNA to the level of control airways in the presence of L-NNA (P < 0.01 all). Similar to nor-NOHA, exogenous L-arginine increased EFS-induced airway relaxation (P < 0.05 all). CONCLUSION: The results indicate that endogenous arginase activity attenuates iNANC nerve-mediated airway relaxation by inhibition of NO generation, presumably by limiting L-arginine availability to nNOS

    Decreased systemic bioavailability of L-arginine in patients with cystic fibrosis

    Get PDF
    BACKGROUND: L-arginine is the common substrate for nitric oxide synthases and arginases. Increased arginase levels in the blood of patients with cystic fibrosis may result in L-arginine deficiency and thereby contribute to low airway nitric oxide formation and impaired pulmonary function. METHODS: Plasma amino acid and arginase levels were studied in ten patients with cystic fibrosis before and after 14 days of antibiotic treatment for pulmonary exacerbation. Patients were compared to ten healthy non-smoking controls. RESULTS: Systemic arginase levels measured by ELISA were significantly increased in cystic fibrosis with exacerbation compared to controls (17.3 ± 12.0 vs. 4.3 ± 3.4 ng/ml, p < 0.02). Arginase levels normalized with antibiotic treatment. Plasma L-arginine was significantly reduced before (p < 0.05) but not after treatment. In contrast, L-ornithine, proline, and glutamic acid, all downstream products of arginase activity, were normal before, but significantly increased after antibiotic therapy. Bioavailability of L-arginine was significantly reduced in cystic fibrosis before and after exacerbation (p < 0.05, respectively). CONCLUSION: These observations provide further evidence for a disturbed balance between the L-arginine metabolic pathways in cystic fibrosis
    corecore