'Map and zap' - electrode catheter techniques for treatment of supraventricular tachycardias

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Normal left ventricular function does not protect against propafenone-induced incessant ventricular tachycardia

Propafenone is a class Ic anti-arrhythmic agent with mild B-blocking properties which has recently become available in South Africa. We have used the drug in 3 patients with sustained m.onomorphic ventricular tachycardia not due to ischaemic heart disease. All had norm.al left ventricular function; 1 had Wegener's granulom.atosis and 2 had arrhythmogenic right ventricular dysplasia. In the latter 2, propafenone provoked incessant monomorphic ventricular tachycardia which persisted for m.ore than 24 hours despite repeated efforts at term.ination. The morphology was similar to the patients' spontaneous ventricular tachycardia, but the rate was slower and the QRS complexes broader, consistent with propafenone's marked ability to slow intraventricular conduction. It is postulated that incessant tachycardia results from. perpetuation of re-entry due to marked conduction slowing produced by the drug. Previous reports have suggested that this is most likely to occur in patients with poor left ventricular function, but our experience indicates that those with normal left ventricular function are also at risk, particularly if the substrate for reentry is present. Propafenone, like all other powerful antiarrhythmic agents, may provoke life-threatening arrhythmias and should be used with great caution after due consideration of the indications, even in patients with norm.al left ventricular function

Central pain mechanisms predict physical inactivity at 1-year in individuals with knee pain

Purpose: Pain is the primary clinical manifestation in individuals with osteoarthritis (OA). It is an unpleasant and distressing experience, particularly during weight-bearing activities, inhibiting activity, and reducing quality of life. Two groups of mechanisms cause OA pain: peripheral (local joint pain from joint pathology) and central (severely worsened pain due to brain and spinal cord processing of peripheral nociceptive inputs). Each contributes to varying extents at different times to an individual’s OA pain. Pain and physical inactivity are often treated by discrete interventions, but in reality are tightly integrated. Several traits linked to central pain processing, such as catastrophising, depression and fatigue, have been independently linked to physical inactivity. This study aimed to explore cross sectional and longitudinal associations between central pain mechanisms and physical inactivity in individuals with knee pain.Methods: This study is an analysis of the first 5,000 participants with validated questionnaire data, aged ≥40 who completed FRAIL in the Investigating Musculoskeletal Health and Wellbeing (IMH&W) cohort (n= >8,570), based in the East Midlands region of the UK. Participants completed a questionnaire at baseline and 1-year later, including participant characteristics and 0 to 10 numerical rating scale (NRS) of pain in the most troublesome joint in the past 4-weeks. Central pain Mechanisms Trait (CMT) was measured using the Central Aspects of Pain in the Knee (CAP-Knee) questionnaire, comprising 8-items addressing anxiety, depression, catastrophising, neuropathic-like pain, fatigue, sleep disturbance, pain distribution and cognitive impact, giving a maximum total score of 16. Self-reported physical activity was measured using the FiND questionnaire item, through which participants report their level of physical activity as either regular (at least 2-4 hours a week) or none/mainly sedentary. Associations were explored using logistic regression models. Data are presented as median (interquartile range), odds ratios (OR), and 95% confidence intervals.Results: 2473 participants completed the FRAIL, of whom 722 participants reported knee as their most troublesome joint and an NRS pain ≥1, of whom 407 participants had self-reported physical activity data also at 1-year. The 722 participants had a median (IQR) age 72 (65-77), with a BMI of 28.08 (24.82-31.64), 55% were female, and 70% reported being regularly physically active at baseline. Median (IQR) CAP-Knee was 8 (5-11) and NRS pain was 6 (4-8). Individuals who did not complete follow-up data had significantly higher baseline NRS pain, CAP-Knee, lower BMI, and were more sedentary. For each unit increase in NRS pain or CAP-Knee at baseline, participants were more likely to be sedentary at baseline (NRS OR=1.25 (95%CI 1.16, 1.36), P<0.001; CAP-Knee OR=1.20 (95%CI 1.14, 1.26), P<0.001) and follow-up (NRS OR=1.17 (95%CI 1.05, 1.30), P=0.004; CAP-Knee OR=1.15 (95%CI 1.08, 0.93), P<0.001). When adjusted for potential confounders age, sex, BMI, knee replacement the association between baseline CAP-Knee and baseline physical activity remained significant (aOR=1.19 (95%CI 1.13, 1.25) P<0.001, Table 1), and significantly predicted 1-year physical inactivity (aOR=1.13, (95%CI 1.06, 1.21) P<0.001, Table 2). The depression item was the only CAP-Knee item significantly associated with physical activity levels in both cross-sectional and longitudinal analyses. Baseline fatigue was significantly associated with baseline physical activity.Conclusions: Higher scores for baseline central pain mechanisms were associated with lower baseline physical activity and predicted 1-year physical inactivity. Our data highlight the integration between pain and physical activity. The observed associations between central pain mechanisms and physical activity might indicate shared neurological mechanisms, and central pain mechanisms might also act as barriers to increasing activity. Specific central mechanisms, particularly depression and fatigue, might be important targets to help improve physical activity in people with knee pain

The roles of the formal and informal sectors in the provision of effective science education

For many years, formal school science education has been criticised by students, teachers, parents and employers throughout the world. This article presents an argument that a greater collaboration between the formal and the informal sector could address some of these criticisms. The causes for concern about formal science education are summarised and the major approaches being taken to address them are outlined. The contributions that the informal sector currently makes to science education are identified. It is suggested that the provision of an effective science education entails an enhanced complementarity between the two sectors. Finally, there is a brief discussion of the collaboration and communication still needed if this is to be effective

Grain Surface Models and Data for Astrochemistry

AbstractThe cross-disciplinary field of astrochemistry exists to understand the formation, destruction, and survival of molecules in astrophysical environments. Molecules in space are synthesized via a large variety of gas-phase reactions, and reactions on dust-grain surfaces, where the surface acts as a catalyst. A broad consensus has been reached in the astrochemistry community on how to suitably treat gas-phase processes in models, and also on how to present the necessary reaction data in databases; however, no such consensus has yet been reached for grain-surface processes. A team of ∼25 experts covering observational, laboratory and theoretical (astro)chemistry met in summer of 2014 at the Lorentz Center in Leiden with the aim to provide solutions for this problem and to review the current state-of-the-art of grain surface models, both in terms of technical implementation into models as well as the most up-to-date information available from experiments and chemical computations. This review builds on the results of this workshop and gives an outlook for future directions

Measurement of the cross section for isolated-photon plus jet production in pp collisions at √s=13 TeV using the ATLAS detector

The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb−1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements