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51.
52.
Audrey Dionne Anne Fournier Nagib Dahdah Dominic Abrams Paul Khairy Sylvia Abadir 《The Canadian journal of cardiology》2018,34(1):66-72
Background
QT-interval variations in response to exercise-induced increases in heart rate have been reported in children and adults in the diagnosis of long QT syndrome (LQTS). A quick standing challenge has been proposed as an alternative provocative test in adults, with no pediatric data yet available.Methods
A standing test was performed in 100 healthy children (mean age, 9.7 ± 3.1 years) after 10 minutes in a supine position with continuous electrocardiographic recording. QT intervals were measured at baseline, at maximal heart rate, at maximal QT, and at each minute of a 5-minute recovery while standing. Measurements were taken in leads II/V5 and were corrected for heart rate (QTc).Results
On standing, the heart rate increased by 29 ± 10 beats per minute (bpm). The QT interval was similar at baseline and on standing (394 ± 34 ms vs 394 ± 34 ms; P = 1.0). However, QTc increased from 426 ± 21 to 509 ± 41 ms (P < 0.001). The 95th percentile for QTc at baseline and maximal heart rate was 457 ms and 563 ms, respectively. At 1 minute of recovery, the QT interval was shorter (375 ± 31 ms) compared with baseline (394 ± 34 ms; P < 0.001) and standing (394 ± 34 ms; P < 0.001). QTc reached baseline values after 1 minute of recovery and remained stable thereafter (423 ± 23 ms at 1 minute; 426 ± 22 ms at 5 minutes; P = 1.0).Conclusions
This first characterization of QTc changes on standing in children shows substantial alterations, which are greater than those seen in adults. Two-thirds of the children would have been misclassified as having LQTS by adult criteria, indicating the need to create child-specific standards. 相似文献53.
54.
55.
Andreas W. Schoenenberger André Moser Dominic Bertschi Peter Wenaweser Stephan Windecker Thierry Carrel Andreas E. Stuck Stefan Stortecky 《JACC: Cardiovascular Interventions》2018,11(4):395-403
Objectives
This study sought to evaluate whether frailty improves mortality prediction in combination with the conventional scores.Background
European System for Cardiac Operative Risk Evaluation (EuroSCORE) or Society of Thoracic Surgeons (STS) score have not been evaluated in combined models with frailty for mortality prediction after transcatheter aortic valve replacement (TAVR).Methods
This prospective cohort comprised 330 consecutive TAVR patients ≥70 years of age. Conventional scores and a frailty index (based on assessment of cognition, mobility, nutrition, and activities of daily living) were evaluated to predict 1-year all-cause mortality using Cox proportional hazards regression (providing hazard ratios [HRs] with confidence intervals [CIs]) and measures of test performance (providing likelihood ratio [LR] chi-square test statistic and C-statistic [CS]).Results
All risk scores were predictive of the outcome (EuroSCORE, HR: 1.90 [95% CI: 1.45 to 2.48], LR chi-square test statistic 19.29, C-statistic 0.67; STS score, HR: 1.51 [95% CI: 1.21 to 1.88], LR chi-square test statistic 11.05, C-statistic 0.64; frailty index, HR: 3.29 [95% CI: 1.98 to 5.47], LR chi-square test statistic 22.28, C-statistic 0.66). A combination of the frailty index with either EuroSCORE (LR chi-square test statistic 38.27, C-statistic 0.72) or STS score (LR chi-square test statistic 28.71, C-statistic 0.68) improved mortality prediction. The frailty index accounted for 58.2% and 77.6% of the predictive information in the combined model with EuroSCORE and STS score, respectively. Net reclassification improvement and integrated discrimination improvement confirmed that the added frailty index improved risk prediction.Conclusions
This is the first study showing that the assessment of frailty significantly enhances prediction of 1-year mortality after TAVR in combined risk models with conventional risk scores and relevantly contributes to this improvement. 相似文献56.
Kranzer K McGrath N Saul J Crampin AC Jahn A Malema S Mulawa D Fine PE Zaba B Glynn JR 《Tropical medicine & international health : TM & IH》2008,13(11):1341-1350
Objective To investigate individual, household and community factors associated with HIV test refusal in a counselling and testing programme offered at population level in rural Malawi. Methods HIV counselling and testing was offered to individuals aged 18–59 at their homes. Individual variables were collected by interviews and physical examinations. Household variables were determined as part of a previous census. Multivariate models allowing for household and community clustering were used to assess associations between HIV test refusal and explanatory variables. Results Of 2303 eligible adults, 2129 were found and 1443 agreed to HIV testing. Test refusal was less likely by those who were never married [adjusted odds ratio (aOR) 0.50 for men (95% CI 0.32; 0.80) and 0.44 (0.21; 0.91) for women] and by farmers [aOR 0.70 (0.52; 0.96) for men and 0.59 (0.40; 0.87) for women]. A 10% increase in cluster refusal rates increased the odds of refusal by 1.48 (1.32; 1.66) in men and 1.68 (1.32; 2.12) in women. Women counsellors increased the odds of refusal by 1.39 (1.00; 1.92) in men. Predictors of HIV test refusal in women were refusal of the husband as head of household [aOR 15.08 (9.39; 24.21)] and living close to the main road [aOR 6.07 (1.76; 20.98)]. Common reasons for refusal were fear of testing positive, previous HIV test, knowledge of HIV serostatus and the need for more time to think. Conclusion Successful VCT strategies need to encourage couples counselling and should involve participation of men and communities. 相似文献
57.
PurposeParkinson disease (PD) medications are not readily available in all countries. Citicoline increases dopamine synthesis and inhibits dopamine uptake. This systematic review aims to synthesize current existing evidence on the efficacy of citicoline adjunctive therapy in improving PD symptoms.MethodsAn extensive literature search of Scopus, Embase, PubMed, Cochrane Library, and Google Scholar was conducted for articles published on or before December 31, 2019. The studies were screened and selected by 2 independent reviewers. We included all studies that explored the efficacy of citicoline as an adjunct therapy in PD.FindingsA total of 7 studies (2 crossover, 3 randomized controlled, and 2 open prospective studies) were included. Despite the varied outcome tools, this review found that patients with PD who were taking citicoline had significant improvement in rigidity, akinesia, tremor, handwriting, and speech. Citicoline allowed effective reduction of levodopa by up to 50%. Significant improvement in cognitive status evaluation was also noted with citicoline adjunctive therapy.ImplicationsCiticoline adjuvant therapy has beneficial effects as an adjuvant therapy in patients with PD. However, due to the heterogeneity of the studies, there is a need for more high-quality studies. 相似文献
58.
59.
Trevisan Dominic A. Parker Termara McPartland James C. 《Journal of autism and developmental disorders》2021,51(10):3483-3491
Journal of Autism and Developmental Disorders - Interoceptive awareness refers to one’s ability to detect, discriminate, and regulate internal bodily and mental processes. Interoceptive... 相似文献
60.
Judith F. Nottage Paul D. Morrison Steve C. R. Williams Dominic H. ffytche 《Brain topography》2013,26(1):50-61
Neural oscillations in the gamma band are of increasing interest, but separating them from myogenic electrical activity has proved difficult. A novel algorithm has been developed to reduce the effect of tonic scalp and neck muscle activity on the gamma band of the EEG. This uses mathematical modelling to fit individual muscle spikes and then subtracts them from the data. The method was applied to the detection of motor associated gamma in two separate groups of eight subjects using different sampling rates. A reproducible increase in high gamma (65–85 Hz) magnitude occurred immediately after the motor action in the left central area (p = 0.02 and p = 0.0002 for the two cohorts with individually optimized algorithm parameters, compared to p = 0.03 and p = 0.16 before correction). Whilst the magnitude of this event-related gamma synchronisation was not reduced by the application of the EMG reduction algorithm, the baseline left central gamma magnitude was significantly reduced by an average of 23 % with a faster sampling rate (p < 0.05). In comparison, at left and right temporo-parietal locations the gamma amplitude was reduced by 60 and 54 % respectively (p < 0.05). The reduction of EMG contamination by fitting and subtraction of individual spikes shows promise as a method of improving the signal to noise ratio of high frequency neural oscillations in scalp EEG. 相似文献