291 research outputs found

    Interactions of short-term and chronic treadmill training with aging of the left ventricle of the heart

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    With aging, there is a decline in cardiac function accompanying increasing risk of arrhythmias. These effects are likely to be mechanistically associated with age-associated changes in calcium regulation within cardiac myocytes. Previous studies suggest that lifelong exercise can potentially reduce age-associated changes in the heart. Although exercise itself is associated with changes in cardiac function, little is known about the interactions of aging and exercise with respect to myocyte calcium regulation. To investigate this, adult (12 months) and old (24 months) C57/Bl6 mice were trained using moderate-intensity treadmill running. In response to 10 weeks’ training, comparable cardiac hypertrophic responses were observed, although aging independently associated with additional cardiac hypertrophy. Old animals also showed increased L- and T-type calcium channels, the sodium–calcium exchange, sarcoendoplasmic reticulum calcium ATPase, and collagen (by 50%, 92%, 66%, 88%, and 113% respectively). Short-term exercise training increased D-type and T-type calcium channels in old animals only, whereas an increase in sodium–calcium exchange was seen only in adult animals. Long-term (12 months) training generally opposed the effects of aging. Significant hypertrophy remained in long-term trained old animals, but levels of sarcoendoplasmic reticulum calcium ATPase, sodium–calcium exchange, and collagen were not significantly different from those found in the adult trained animals

    Disorder raises the critical temperature of a cuprate superconductor

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    With the discovery of charge density waves (CDW) in most members of the cuprate high temperature superconductors, the interplay between superconductivity and CDW has become a key point in the debate on the origin of high temperature superconductivity. Some experiments in cuprates point toward a CDW state competing with superconductivity, but others raise the possibility of a CDW-superconductivity intertwined order, or more elusive pair-density wave (PDW). Here we have used proton irradiation to induce disorder in crystals of La1.875_{1.875}Ba0.125_{0.125}CuO4_4 and observed a striking 50% increase of TcT_\mathrm{c} accompanied by a suppression of the CDW. This is in clear contradiction with the behaviour expected of a d-wave superconductor for which both magnetic and non-magnetic defects should suppress TcT_\mathrm{c}. Our results thus make an unambiguous case for the strong detrimental effect of the CDW on bulk superconductivity in La1.875_{1.875}Ba0.125_{0.125}CuO4_4. Using tunnel diode oscillator (TDO) measurements, we find evidence for dynamic layer decoupling in PDW phase. Our results establish irradiation-induced disorder as a particularly relevant tuning parameter for the many families of superconductors with coexisting density waves, which we demonstrate on superconductors such as the dichalcogenides and Lu5_5Ir4_4Si10_{10}.Comment: 10 pages, 7 figure

    Treatment of classical Hodgkin lymphoma in young adults aged 18-30 years with a modified paediatric Hodgkin lymphoma protocol. Results of a multicentre phase II clinical trial (CRUK/08/012)

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    This phase II trial was designed to determine the safety and efficacy of a modified paediatric risk-stratified protocol in young adults (18-30 years) with classical Hodgkin Lymphoma. The primary end-point was neurotoxicity rate. The incidence of grade 3 neurotoxicity was 11% (80% CI, 5-19%); a true rate of neuropathy of >15% cannot be excluded. Neuropathy and associated deterioration in quality of life was largely reversible. The overall response rate was 100% with 40% complete remission (CR) rate. Twelve months disease-free survival (DFS) was 91%. We demonstrate that a risk-stratified paediatric combined modality treatment approach can be delivered to young adults without significant irreversible neuropathy

    Evolution of 18F-FDG-PET/CT findings in patients following COVID-19 pneumonia: An Initial Investigation

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    Background: The evolution of pulmonary 18F-FDG uptake is unknown in patients with pneumonia due to SARS-CoV-2 (COVID-19 pneumonia) and in those with persistent respiratory symptoms post-COVID-19 termed Post-COVID-19 Lung-Disease (PCLD). The aim of this study was to assess the temporal evolution of pulmonary 18F-FDG uptake and identify a potential role for the use of 18F-FDG-PET/CT imaging in the management of these patients. Methods: Clinical data and CT imaging of all patients that underwent 18F-FDG-PET/CT imaging at UCLH, Lon-don during the UK pandemic were reviewed to find evidence of active or recovered SARS-CoV-2 infection. Results of PCR tests were used where available. Patients were divided in to acute (early and late) COVID-19 pneumonia, PCLD and asymptomatic recovery. 18F-FDG uptake in the lungs was measured as a target-to-background ratio (SUVmax/SUVmin) TBRlung which was compared to temporal-stage and plasma CRP. Results: There were 50 patients in total (median 61y, range 18-87y, 32-male): 23 incidental acute COVID-19 pneumonia cases identified retrospectively (8 Early, 15 Late), 9 asymptomatic recovered patients, and 18 cases performed for PCLD. In acute COVID-19 patients <3 weeks since disease onset TBRlung was strongly correlated with time since disease onset (rs=0.81, p<0.001)

    The association between patterns of atrial fibrillation, anticoagulation, and cardiovascular events.

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    AIMS: Guidelines do not recommend to take pattern of atrial fibrillation (AF) into account for the indication of anticoagulation (AC). We assessed AF pattern and the risk of cardiovascular events during 2-years of follow-up. METHODS AND RESULTS: We categorized AF as paroxysmal, persistent, or permanent in 29 181 patients enrolled (2010-15) in the Global Anticoagulant Registry In the FIELD of AF (GARFIELD-AF). We used multivariable Cox regression to assess the risks of stroke/systemic embolism (SE) and death across patterns of AF, and whether this changed with AC on outcomes. Atrial fibrillation pattern was paroxysmal in 14 344 (49.2%), persistent in 8064 (27.6%), and permanent 6773 (23.2%) patients. Median CHA2DS2-VASc, GARFIELD-AF, and HAS-BLED scores assessing the risk of stroke/SE and/or bleeding were similar across AF patterns, but the risk of death, as assessed by the GARFIELD-AF risk calculator, was higher in non-paroxysmal than in paroxysmal AF patterns. During 2-year follow-up, after adjustment, non-paroxysmal AF patterns were associated with significantly higher rates of all-cause death, stroke/SE, and new/worsening congestive heart failure (CHF) than paroxysmal AF in non-anticoagulated patients only. In anticoagulated patients, a significantly higher risk of death but not of stroke/SE and new/worsening CHF persisted in non-paroxysmal compared with paroxysmal AF patterns. CONCLUSION: In non-anticoagulated patients, non-paroxysmal AF patterns were associated with higher risks of stroke/SE, new/worsening HF and death than paroxysmal AF. In anticoagulated patients, the risk of stroke/SE and new/worsening HF was similar across all AF patterns. Thus AF pattern is no longer prognostic for stroke/SE when patients are treated with anticoagulants. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362
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