1,106 research outputs found
Difference in symptom severity between early and late grass pollen season in patients with seasonal allergic rhinitis
<p>Abstract</p> <p>Background</p> <p>For the development of forecasts for seasonal allergic rhinitis symptoms, it is essential to understand the relationship between grass pollen concentrations and the symptoms of grass pollen allergic patients.</p> <p>Objective</p> <p>The aim of this study was to delineate this relationship between seasonal allergic rhinitis symptoms and grass pollen concentrations in the Netherlands.</p> <p>Methods</p> <p>Grass pollen allergic patients (n = 80 [2007] - 84 [2008]) were enrolled into the study. They were asked to enter their seasonal allergic rhinitis symptoms (runny nose, sneezing, blocked nose, post nasal drip, and eye symptoms) daily on a scale from 0 to 3 to the study centre either by short message service (SMS) or by internet from May-July 2007 and April-July 2008. Daily pollen counts were used to define the early and the late grass pollen season as the period 'before and during' respectively 'after' the first grass pollen peak (more than 150 pollen/m<sup>3</sup>).</p> <p>Results</p> <p>At similar grass pollen concentrations, the daily mean of the individual maximum symptom scores reported in the early season were higher as compared to that reported in the late season [differences of -0.41 (2007) and -0.30 (2008)]. This difference could not be explained by medication use by the patients nor by co-sensitization to birch.</p> <p>Conclusions</p> <p>We conclude that seasonal allergic rhinitis symptoms at similar grass pollen concentrations are more severe in the early flowering season as compared to those in the late flowering season. This finding is not only relevant for development of forecasts for seasonal allergic rhinitis symptoms but also for understanding symptom development and planning and analysis of clinical studies.</p
Specialist training in Fiji: Why do graduates migrate, and why do they remain? A qualitative study
<p>Abstract</p> <p>Background</p> <p>Specialist training was established in the late 1990s at the Fiji School of Medicine. Losses of graduates to overseas migration and to the local private sector prompted us to explore the reasons for these losses from the Fiji public workforce.</p> <p>Methods</p> <p>Data were collected on the whereabouts and highest educational attainments of the 66 Fiji doctors who had undertaken specialist training to at least the diploma level between 1997 and 2004. Semistructured interviews focusing on career decisions were carried out with 36 of these doctors, who were purposively sampled to include overseas migrants, temporary overseas trainees, local private practitioners and public sector doctors.</p> <p>Results</p> <p>120 doctors undertook specialist training to at least the diploma level between 1997 and 2004; 66 of the graduates were Fiji citizens or permanent residents; 54 originated from other countries in the region. Among Fiji graduates, 42 completed a diploma and 24 had either completed (21) or were enrolled (3) in a master's programme. Thirty-two (48.5%) were working in the public sectors, four (6.0%) were temporarily training overseas, 30.3% had migrated overseas and the remainder were mostly in local private practice. Indo-Fijian ethnicity and non-completion of full specialist training were associated with lower retention in the public sectors, while gender had little impact. Decisions to leave the public sectors were complex, with concerns about political instability and family welfare predominating for overseas migrants, while working conditions not conducive to family life or frustrations with career progression predominated for local private practitioners. Doctors remaining in the public sectors reported many satisfying aspects to their work despite frustrations, though 40% had seriously considered resigning from the public service and 60% were unhappy with their career progression.</p> <p>Conclusion</p> <p>Overall, this study provides some support for the view that local or regional postgraduate training may increase retention of doctors. Attention to career pathways and other sources of frustration, in addition to encouragement to complete training, should increase the likelihood of such programmes' reaching their full potentials.</p
A Partial Structural and Functional Rescue of a Retinitis Pigmentosa Model with Compacted DNA Nanoparticles
Previously we have shown that compacted DNA nanoparticles can drive high levels of transgene expression after subretinal injection in the mouse eye. Here we delivered compacted DNA nanoparticles containing a therapeutic gene to the retinas of a mouse model of retinitis pigmentosa. Nanoparticles containing the wild-type retinal degeneration slow (Rds) gene were injected into the subretinal space of rds+/− mice on postnatal day 5. Gene expression was sustained for up to four months at levels up to four times higher than in controls injected with saline or naked DNA. The nanoparticles were taken up into virtually all photoreceptors and mediated significant structural and biochemical rescue of the disease without histological or functional evidence of toxicity. Electroretinogram recordings showed that nanoparticle-mediated gene transfer restored cone function to a near-normal level in contrast to transfer of naked plasmid DNA. Rod function was also improved. These findings demonstrate that compacted DNA nanoparticles represent a viable option for development of gene-based interventions for ocular diseases and obviate major barriers commonly encountered with non-viral based therapies
Analytic philosophy for biomedical research: the imperative of applying yesterday's timeless messages to today's impasses
The mantra that "the best way to predict the future is to invent it" (attributed to the computer scientist Alan Kay) exemplifies some of the expectations from the technical and innovative sides of biomedical research at present. However, for technical advancements to make real impacts both on patient health and genuine scientific understanding, quite a number of lingering challenges facing the entire spectrum from protein biology all the way to randomized controlled trials should start to be overcome. The proposal in this chapter is that philosophy is essential in this process. By reviewing select examples from the history of science and philosophy, disciplines which were indistinguishable until the mid-nineteenth century, I argue that progress toward the many impasses in biomedicine can be achieved by emphasizing theoretical work (in the true sense of the word 'theory') as a vital foundation for experimental biology. Furthermore, a philosophical biology program that could provide a framework for theoretical investigations is outlined
The impact of laxative use upon symptoms in patients with proven slow transit constipation
<p>Abstract</p> <p>Background</p> <p>Constipation severity is often defined by symptoms including feelings of complete evacuation, straining, stool frequency and consistency. These descriptors are mostly obtained in the absence of laxative use. For many constipated patients laxative usage is ubiquitous and long standing. Our aim was to determine the impact of laxative use upon the stereotypic constipation descriptors.</p> <p>Methods</p> <p>Patients with confirmed slow transit constipation completed 3-week stool diaries, detailing stool frequency and form, straining, laxative use and pain and bloating scores. Each diary day was classified as being under laxative affect (laxative affected days) or not (laxative unaffected days). Unconditional logistic regression was used to assess the affects of laxatives on constipation symptoms.</p> <p>Results</p> <p>Ninety four patients with scintigraphically confirmed slow transit constipation were enrolled in the study. These patients reported a stool frequency of 5.6 ± 4.3 bowel motions/week, only 21 patients reported <3 bowel motions/week. Similarly, 21 patients reported a predominant hard stool at defecation. The majority (90%) of patients reported regular straining. A regular feeling of complete evacuation was reported in just 7 patients. Daily pain and/or bloating were reported by 92% of patients. When compared with laxative unaffected days, on the laxative affected days patients had a higher stool frequency (OR 2.23; <it>P </it><0.001) and were more likely to report loose stools (OR 1.64; <it>P </it><0.009). Laxatives did not increase the number of bowel actions associated with a feeling of complete evacuation. Laxative use had no affect upon straining, pain or bloating scores</p> <p>Conclusions</p> <p>The reporting of frequent and loose stools with abdominal pain and/or bloating is common in patients with slow transit constipation. While laxative use is a significant contributor to altering stool frequency and form, laxatives have no apparent affect on pain or bloating or upon a patients feeling of complete evacuation. These factors need to be taken into account when using constipation symptoms to define this population.</p
Proposing a Tool for Supply Chain Configuration: An Application to Customised Production
The full implementation of collaborative production networks is crucial for companies willing to respond to consumer demand strongly focused on product customisation. This chapter proposes an approach to evaluate the performance of different Supply Chain (SC) configurations in a customised production context. The model is based on discrete-event simulation and is applied to the case of supply chain in the fashion sector to support the comparison between mass and customised production. A prototype web-based interface is also developed and proposed to facilitate the use of the model not only for experts in simulation but for any user in the SC management field
The contributions of muscarinic receptors and changes in plasma aldosterone levels to the anti-hypertensive effect of Tulbaghia violacea
Background: Tulbaghia violacea Harv. (Alliaceae) is used to treat various ailments, including hypertension (HTN) in
South Africa. This study aims to evaluate the contributions of muscarinic receptors and changes in plasma
aldosterone levels to its anti-hypertensive effect.
Methods: In the acute experiments, methanol leaf extracts (MLE) of T. violacea (30–120 mg/kg), muscarine (0.16
-10 μg/kg), and atropine (0.02 - 20.48 mg/kg), and/or the vehicle (dimethylsulfoxide (DMSO) and normal saline (NS))
were respectively and randomly administered intravenously in a group of spontaneously hypertensive (SHR)
weighing 300 to 350 g and aged less than 5 months. Subsequently, T. violacea (60 mg/kg) or muscarine (2.5 μg/kg)
was infused into eight SHRs, 20 min after atropine (5.12 mg/kg) pre-treatment. In the chronic (21 days) experiments,
the SHRs were randomly divided into three groups, and given the vehicle (0.2 ml/day of DMSO and NS), T. violacea
(60 mg/kg/day) and captopril (10 mg/kg/day) respectively into the peritoneum, to investigate their effects on blood
pressure (BP), heart rate (HR), and plasma aldosterone levels. Systolic BP and HR were measured using tail-cuff
plethysmography during the intervention. BP and HR were measured via a pressure transducer connecting the
femoral artery and the Powerlab at the end of each intervention in the acute experiment; and on day 22 in the
chronic experiment.
Results: In the acute experiments, T. violacea, muscarine, and atropine significantly (p < 0.05) reduced BP
dose-dependently. T. violacea and muscarine produced dose-dependent decreases in HR, while the effect of
atropine on HR varied. After atropine pre-treatment, dose-dependent increases in BP and HR were observed with
T. violacea; while the BP and HR effects of muscarine were nullified. In the chronic experiments, the T. violaceatreated
and captropril-treated groups had signicantly lower levels of aldosterone in plasma when compared to
vehicle-treated group. Compared to the vehicle-treated group, significant reduction in BP was only seen in the
captopril-treated group; while no difference in HR was observed among the groups.
Conclusion: The results obtained in this study suggest that stimulation of the muscarinic receptors and a reduction
in plasma aldosterone levels contribute to the anti-hypertesive effect of T. violacea.IS
Implementing the LifeSkills Training drug prevention program: factors related to implementation fidelity
<p>Abstract</p> <p>Background</p> <p>Widespread replication of effective prevention programs is unlikely to affect the incidence of adolescent delinquency, violent crime, and substance use until the quality of implementation of these programs by community-based organizations can be assured.</p> <p>Methods</p> <p>This paper presents the results of a process evaluation employing qualitative and quantitative methods to assess the extent to which 432 schools in 105 sites implemented the LifeSkills Training (LST) drug prevention program with fidelity. Regression analysis was used to examine factors influencing four dimensions of fidelity: adherence, dosage, quality of delivery, and student responsiveness.</p> <p>Results</p> <p>Although most sites faced common barriers, such as finding room in the school schedule for the program, gaining full support from key participants (i.e., site coordinators, principals, and LST teachers), ensuring teacher participation in training workshops, and classroom management difficulties, most schools involved in the project implemented LST with very high levels of fidelity. Across sites, 86% of program objectives and activities required in the three-year curriculum were delivered to students. Moreover, teachers were observed using all four recommended teaching practices, and 71% of instructors taught all the required LST lessons. Multivariate analyses found that highly rated LST program characteristics and better student behavior were significantly related to a greater proportion of material taught by teachers (adherence). Instructors who rated the LST program characteristics as ideal were more likely to teach all lessons (dosage). Student behavior and use of interactive teaching techniques (quality of delivery) were positively related. No variables were related to student participation (student responsiveness).</p> <p>Conclusion</p> <p>Although difficult, high implementation fidelity by community-based organizations can be achieved. This study suggests some important factors that organizations should consider to ensure fidelity, such as selecting programs with features that minimize complexity while maximizing flexibility. Time constraints in the classroom should be considered when choosing a program. Student behavior also influences program delivery, so schools should train teachers in the use of classroom management skills. This project involved comprehensive program monitoring and technical assistance that likely facilitated the identification and resolution of problems and contributed to the overall high quality of implementation. Schools should recognize the importance of training and technical assistance to ensure quality program delivery.</p
Effects of phlebotomy-induced reduction of body iron stores on metabolic syndrome: results from a randomized clinical trial
<p>Abstract</p> <p>Background</p> <p>Metabolic syndrome (METS) is an increasingly prevalent but poorly understood clinical condition characterized by insulin resistance, glucose intolerance, dyslipidemia, hypertension, and obesity. Increased oxidative stress catalyzed by accumulation of iron in excess of physiologic requirements has been implicated in the pathogenesis of METS, but the relationships between cause and effect remain uncertain. We tested the hypothesis that phlebotomy-induced reduction of body iron stores would alter the clinical presentation of METS, using a randomized trial.</p> <p>Methods</p> <p>In a randomized, controlled, single-blind clinical trial, 64 patients with METS were randomly assigned to iron reduction by phlebotomy (n = 33) or to a control group (n = 31), which was offered phlebotomy at the end of the study (waiting-list design). The iron-reduction patients had 300 ml of blood removed at entry and between 250 and 500 ml removed after 4 weeks, depending on ferritin levels at study entry. Primary outcomes were change in systolic blood pressure (SBP) and insulin sensitivity as measured by Homeostatic Model Assessment (HOMA) index after 6 weeks. Secondary outcomes included HbA1c, plasma glucose, blood lipids, and heart rate (HR).</p> <p>Results</p> <p>SBP decreased from 148.5 ± 12.3 mmHg to 130.5 ± 11.8 mmHg in the phlebotomy group, and from 144.7 ± 14.4 mmHg to 143.8 ± 11.9 mmHg in the control group (difference -16.6 mmHg; 95% CI -20.7 to -12.5; <it>P </it>< 0.001). No significant effect on HOMA index was seen. With regard to secondary outcomes, blood glucose, HbA1c, low-density lipoprotein/high-density lipoprotein ratio, and HR were significantly decreased by phlebotomy. Changes in BP and HOMA index correlated with ferritin reduction.</p> <p>Conclusions</p> <p>In patients with METS, phlebotomy, with consecutive reduction of body iron stores, lowered BP and resulted in improvements in markers of cardiovascular risk and glycemic control. Blood donation may have beneficial effects for blood donors with METS.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01328210">NCT01328210</a></p> <p>Please see related article: <url>http://www.biomedcentral.com/1741-7015/10/53</url></p
Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV
- …