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Laura C. Saunders Chris S. Johns Neil J. Stewart Charlotte J. E. Oram David A. Capener Valentina O. Puntmann Charlie A. Elliot Robin C. Condliffe David G. Kiely Martin J. Graves Jim M. Wild Andy J. Swift 《Journal of cardiovascular magnetic resonance》2018,20(1):78
Background
Native T1 may be a sensitive, contrast-free, non-invasive cardiovascular magnetic resonance (CMR) marker of myocardial tissue changes in patients with pulmonary artery hypertension. However, the diagnostic and prognostic value of native T1 mapping in this patient group has not been fully explored. The aim of this work was to determine whether elevation of native T1 in myocardial tissue in pulmonary hypertension: (a) varies according to pulmonary hypertension subtype; (b) has prognostic value and (c) is associated with ventricular function and interaction.Methods
Data were retrospectively collected from a total of 490 consecutive patients during their clinical 1.5 T CMR assessment at a pulmonary hypertension referral centre in 2015. Three hundred sixty-nine patients had pulmonary hypertension [58?±?15 years; 66% female], an additional 39 had pulmonary hypertension due to left heart disease [68?±?13 years; 60% female], 82 patients did not have pulmonary hypertension [55?±?18; 68% female]. Twenty five healthy subjects were also recruited [58 ±4 years); 51% female]. T1 mapping was performed with a MOdified Look-Locker Inversion Recovery (MOLLI) sequence. T1 prognostic value in patients with pulmonary arterial hypertension was assessed using multivariate Cox proportional hazards regression analysis.Results
Patients with pulmonary artery hypertension had elevated T1 in the right ventricular (RV) insertion point (pulmonary hypertension patients: T1?=?1060?±?90 ms; No pulmonary hypertension patients: T1?=?1020?±?80 ms p <?0.001; healthy subjects T1?=?940?±?50 ms p <?0.001) with no significant difference between the major pulmonary hypertension subtypes. The RV insertion point was the most successful T1 region for discriminating patients with pulmonary hypertension from healthy subjects (area under the curve?=?0.863) however it could not accurately discriminate between patients with and without pulmonary hypertension (area under the curve?=?0.654). T1 metrics did not contribute to prediction of overall mortality (septal: p =?0.552; RV insertion point: p =?0.688; left ventricular free wall: p =?0.258). Systolic interventricular septal angle was a significant predictor of T1 in patients with pulmonary hypertension (p <?0.001).Conclusions
Elevated myocardial native T1 was found to a similar extent in pulmonary hypertension patient subgroups and is independently associated with increased interventricular septal angle. Native T1 mapping may not be of additive value in the diagnostic or prognostic evaluation of patients with pulmonary artery hypertension.64.
Heron Jon Low Nicola Lewis Glyn Macleod John Ness Andy Waylen Andrea 《Archives of sexual behavior》2015,44(3):669-678
Archives of Sexual Behavior - Various factors are associated with sexual activity in adolescence and it is important to identify those that promote healthy and adaptive romantic and sexual... 相似文献
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Emily R. Watts Andrew J.M. Howden Tyler Morrison Pranvera Sadiku Jens Hukelmann Alex von Kriegsheim Bart Ghesquiere Fiona Murphy Ananda S. Mirchandani Duncan C. Humphries Robert Grecian Eilise M. Ryan Patricia Coelho Gio Rodriguez Blanco Tracie M. Plant Rebecca S. Dickinson Andy Finch Wesley Vermaelen Doreen A. Cantrell Moira K. Whyte Sarah R. Walmsley 《The Journal of clinical investigation》2021,131(10)
Limiting dysfunctional neutrophilic inflammation while preserving effective immunity requires a better understanding of the processes that dictate neutrophil function in the tissues. Quantitative mass-spectrometry identified how inflammatory murine neutrophils regulated expression of cell surface receptors, signal transduction networks, and metabolic machinery to shape neutrophil phenotypes in response to hypoxia. Through the tracing of labeled amino acids into metabolic enzymes, proinflammatory mediators, and granule proteins, we demonstrated that ongoing protein synthesis shapes the neutrophil proteome. To maintain energy supplies in the tissues, neutrophils consumed extracellular proteins to fuel central carbon metabolism. The physiological stresses of hypoxia and hypoglycemia, characteristic of inflamed tissues, promoted this extracellular protein scavenging with activation of the lysosomal compartment, further driving exploitation of the protein-rich inflammatory milieu. This study provides a comprehensive map of neutrophil proteomes, analysis of which has led to the identification of active catabolic and anabolic pathways that enable neutrophils to sustain synthetic and effector functions in the tissues. 相似文献
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Daniel R. Brown Ashley R. Warner Sanjoy K. Deb Lewis A. Gough S. Andy Sparks Lars R. McNaughton 《Journal of Science and Medicine in Sport》2021,24(1):92-97
ObjectivesThis study aimed to investigate whether supplementation with 12 mg?day?1 astaxanthin for 7 days can improve exercise performance and metabolism during a 40 km cycling time trial.DesignA randomised, double-blind, crossover design was employed.MethodsTwelve recreationally trained male cyclists (VO2peak: 56.5 ± 5.5 mL?kg?1?min?1, Wmax: 346.8 ± 38.4 W) were recruited. Prior to each experimental trial, participants were supplemented with either 12 mg?day?1 astaxanthin or an appearance-matched placebo for 7 days (separated by 14 days of washout). On day 7 of supplementation, participants completed a 40 km cycling time trial on a cycle ergometer, with indices of exercise metabolism measured throughout.ResultsTime to complete the 40 km cycling time trial was improved by 1.2 ± 1.7% following astaxanthin supplementation, from 70.76 ± 3.93 min in the placebo condition to 69.90 ± 3.78 min in the astaxanthin condition (mean improvement = 51 ± 71 s, p = 0.029, g = 0.21). Whole-body fat oxidation rates were also greater (+0.09 ± 0.13 g?min?1, p = 0.044, g = 0.52), and the respiratory exchange ratio lower (?0.03 ± 0.04, p = 0.024, g = 0.60) between 39–40 km in the astaxanthin condition.ConclusionsSupplementation with 12 mg?day?1 astaxanthin for 7 days provided an ergogenic benefit to 40 km cycling time trial performance in recreationally trained male cyclists and enhanced whole-body fat oxidation rates in the final stages of this endurance-type performance event. 相似文献
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Buijs Sheila B. Stuart Sanne K. Oosterheert Jan Jelrik Karhof Steffi Hoepelman Andy I. M. Renders Nicole H. M. van Petersen André S. Bleeker-Rovers Chantal P. Wever Peter C. Koning Olivier H. J. 《European journal of clinical microbiology & infectious diseases》2021,40(7):1569-1572
We evaluated the long-term serological follow-up of patients with vascular risk factors for chronic Q fever that were previously Coxiella burnetii seropositive. C. burnetii phase I IgG titers were reevaluated in patients that gave informed consent or retrospectively collected in patients already deceased or lost to follow-up. Of 107 patients, 25 (23.4%) became seronegative, 77 (72.0%) retained a profile of past resolved Q fever infection, and five (4.7%) developed chronic Q fever. We urge clinicians to stay vigilant for chronic Q fever beyond two years after primary infection and perform serological testing based on clinical presentation.
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