757 research outputs found
An Analysis Of The Development Of Motor Coordination Of Infants Through Transfer Function Models
Problems associated with motor development in infants have received much attention in the recent years.Early infant spontaneous activity is thought to be an important determinant of later motor ability. Hence, early detection of any irregularities in spontaneous motor patterns such as kicking is important if we are to identify and correct problems that may develop later. Various studies have employed linear cross correlation to examine relationships between joints during spontaneous kicking in young infants. However, the angular displacement curves produced during spontaneous kicking lead to non-linear circular time series. In this paper the couplings between joints and limbs are examined using circular cross correlation function to provide an accurate assessment of the joint relationships. Then, the Box-Jenkins type transfer function approach is used to develop dynamic models to describe intralimb and interlimb coordination of infant kicking in fullterm infants at 12 weeks of age
Evaluation of the SUNHEART Cardiology Outreach Programme
Introduction: The demand for advanced cardiac care and specialised interventions is on the increase and this results in bottlenecks and increased waiting times for patients who require advanced cardiac care. By decentralising cardiac care, and using a hub-and-spoke model, the SUNHEART Outreach Programme of cardiovascular care aims to improve access to advanced cardiac care in the Western Cape. Tygerberg Hospital is the central hub, with the fi rst spoke being Paarl Hospital. Objective: To determine the value of the SUNHEART Outreach Programme to the public health care system. Methods: An audit of patients accessing the OutreachProgramme was performed for the period May 2013 - May 2014 and consequently compared to a historical cohort of patients accessing the health care system during the preceding 6 months, from October 2012 -April 2013. Access to advanced cardiac care was measured in time to initial evaluation, time to defi nitive diagnosis or intervention and patient compliance with appointments. The value to the health care system was also assessed by performing a cost analysis of transport of patients and health care workers, as well as compliance with appointments. We documented the spectrum of disease requiring advanced cardiac care toguide future interventions. Results: Data of 185 patients were included in the audit. Sixty four patients were referred to tertiary care from October 2012 - April 2013 and 121 patients were referred to the outreach facility from May 2013 - May 2014. There was a signifi cant reduction in waiting times with the median days to appointment of the historical cohort being 85 days compared to 18 days in the Outreach Programme cohort (p<0.01). Patient compliance with appointments was signifi cantly superior in the Outreach Programme cohort (90% vs. 56%: p<0.01). Valvular (36.5%) and ischaemic heart disease (35.5%) were the major pathologies requiring access to cardiac care services. Transport costs per patient treated was signifi cantly reduced in the outreach programme cohort (R118,09 vs. R308,77). Conclusion: Decentralisation of services in the form of an Outreach Programme, with a central hub, improves access to advanced cardiac care by decreasing waiting time, improving compliance with appointments and decreasing travel costs
Zoonotic Endocarditis: Is the feather mightier than the sword?
The common causes of infective endocarditis (IE) in South Africa are Staphylococcus aureus, the viridans streptococci and Bartonella species. Infection with Erysipelothrix rhusiopathiae is a rare cause of IE that is usually associated with occupational exposure and can be acquired from humans and animals. It was fi rst reported in 1912 by Gunthar, and thereafter fewer than 60 cases have been reported. We describe a case of Erysipelothrix rhusiopathiae induced endocarditis in Cape Town, South Africa. S
SAHeart 2022;19:24-2
The emerging plasma biomarker Dickkopf-3 (DKK3) and its association with renal and cardiovascular disease in the general population
Dickkopf-3 (DKK3) is an emerging biomarker for cardiovascular disease (CVD) and chronic kidney disease (CKD). Herein, baseline DKK3 plasma levels were measured in 8420 subjects from the Prevention of Renal and Vascular ENd-stage Disease (PREVEND) cohort, a large general population cohort, using enzyme-linked immunosorbent assays. Associations with clinical variables and outcomes were analysed. Median DKK3 level was 32.8 ng/ml (28.0-39.0). In multivariable linear regression analysis, the strongest correlates for plasma DKK3 were age, body mass index and estimated glomerular filtration rate (eGFR). At baseline, 564 (6.7%) subjects had CVD (defined as a myocardial infarction and/or cerebrovascular accident) and 1361 (16.2%) subjects had CKD (defined as eGFR 30 mg/24 h). Of subjects with known CVD and CKD follow-up status (respectively 7828 and 5548), 669 (8.5%) developed CVD and 951 (17.1%) developed CKD (median follow-up respectively 12.5 and 10.2 years). Crude logistic regression analysis revealed that DKK3 levels were associated with prevalent CVD (Odds ratio: 2.14 [1.76-2.61] per DKK3 doubling,
The fibrosis-cell death axis in heart failure
Cardiac stress can induce morphological, structural and functional changes of the heart, referred to as cardiac remodeling. Myocardial infarction or sustained overload as a result of pathological causes such as hypertension or valve insufficiency may result in progressive remodeling and finally lead to heart failure (HF). Whereas pathological and physiological (exercise, pregnancy) overload both stimulate cardiomyocyte growth (hypertrophy), only pathological remodeling is characterized by increased deposition of extracellular matrix proteins, termed fibrosis, and loss of cardiomyocytes by necrosis, apoptosis and/or phagocytosis. HF is strongly associated with age, and cardiomyocyte loss and fibrosis are typical signs of the aging heart. Fibrosis results in stiffening of the heart, conductivity problems and reduced oxygen diffusion, and is associated with diminished ventricular function and arrhythmias. As a consequence, the workload of cardiomyocytes in the fibrotic heart is further augmented, whereas the physiological environment is becoming less favorable. This causes additional cardiomyocyte death and replacement of lost cardiomyocytes by fibrotic material, generating a vicious cycle of further decline of cardiac function. Breaking this fibrosis-cell death axis could halt further pathological and age-related cardiac regression and potentially reverse remodeling. In this review, we will describe the interaction between cardiac fibrosis, cardiomyocyte hypertrophy and cell death, and discuss potential strategies for tackling progressive cardiac remodeling and HF
HE4 Serum Levels Are Associated with Heart Failure Severity in Patients With Chronic Heart Failure
AbstractBackgroundThe novel biomarker human epididymis protein 4 (HE4) shows prognostic value in acute heart failure (HF) patients. We measured HE4 levels in patients with chronic heart failure (CHF) and correlated them to HF severity, kidney function, and HF biomarkers, and determined its predictive value.MethodsSerum HE4 levels in patients (n = 101) with stable CHF with reduced left ventricular ejection fraction (LVEF <45%) from the Vitamin D CHF (VitD-CHF) study (NCT01092130) were compared with those in age- and sex-matched healthy control subjects (n = 58) from the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study.ResultsHE4 levels were higher in CHF compared with control subjects (69.2 pmol/L [interquartile range 55.6-93.8] vs 56.1 pmol/L [46.6-69.0]; P < .001) and were higher with increasing New York Heart Association functional class. Levels were associated with HF risk factors, including age, gender, diabetes, smoking and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP). HE4 demonstrated strong associations with kidney function and HF fibrosis biomarkers. In a multivariable model, we identified creatinine, NT-proBNP, galectin-3, high-sensitive troponin T, and smoking as factors associated with HE4. Independently from these factors, HE4 levels predicted death and HF rehospitalization (5-year follow-up, hazard ratio 3.8; confidence interval 1.31–11.1; P = .014).ConclusionsHE4 levels are increased in CHF, correlate with HF severity and kidney function, and predict HF outcome
Pharmacological myeloperoxidase (MPO) inhibition in an obese/hypertensive mouse model attenuates obesity and liver damage, but not cardiac remodeling
Lifestyle factors are important drivers of chronic diseases, including cardiovascular syndromes, with low grade inflammation as a central player. Attenuating myeloperoxidase (MPO) activity, an inflammatory enzyme associated with obesity, hypertension and heart failure, could have protective effects on multiple organs. Herein, the effects of the novel oral available MPO inhibitor AZM198 were studied in an obese/hypertensive mouse model which displays a cardiac phenotype. Eight week old male C57BL6/J mice received 16 weeks of high fat diet (HFD) combined with angiotensin II (AngII) infusion during the last 4 weeks, with low fat diet and saline infusion as control. Treated animals showed therapeutic AZM198 levels (2.1 µM), corresponding to 95% MPO inhibition. AZM198 reduced elevated circulating MPO levels in HFD/AngII mice to normal values. Independent of food intake, bodyweight increase and fat accumulation were attenuated by AZM198, alongside with reduced visceral adipose tissue (VAT) inflammation and attenuated severity of nonalcoholic steatohepatitis. The HFD/AngII perturbation caused impaired cardiac relaxation and contraction, and increased cardiac hypertrophy and fibrosis. AZM198 treatment did, however, not improve these cardiac parameters. Thus, AZM198 had positive effects on the main lipid controlling tissues in the body, namely adipose tissue and liver. This did, however, not directly result in improved cardiac function
First-phase ejection fraction by CMR predicts outcomes in aortic stenosis
BACKGROUND: First-phase ejection fraction (EF1; the ejection fraction measured during active systole up to the time of maximal aortic flow) measured by transthoracic echocardiography (TTE) is a powerful predictor of outcomes in patients with aortic stenosis. We aimed to assess whether cardiovascular magnetic resonance (CMR) might provide more precise measurements of EF1 than TTE and to examine the correlation of CMR EF1 with measures of fibrosis. METHODS: In 141 patients with at least mild aortic stenosis, we measured CMR EF1 from a short-axis 3D stack and compared its variability with TTE EF1, and its associations with myocardial fibrosis and clinical outcome (aortic valve replacement (AVR) or death). RESULTS: Intra- and inter-observer variation of CMR EF1 (standard deviations of differences within and between observers of 2.3% and 2.5% units respectively) was approximately 50% that of TTE EF1. CMR EF1 was strongly predictive of AVR or death. On multivariable Cox proportional hazards analysis, the hazard ratio for CMR EF1 was 0.93 (95% confidence interval 0.89–0.97, p = 0.001) per % change in EF1 and, apart from aortic valve gradient, CMR EF1 was the only imaging or biochemical measure independently predictive of outcome. Indexed extracellular volume was associated with AVR or death, but not after adjusting for EF1. CONCLUSIONS: EF1 is a simple robust marker of early left ventricular impairment that can be precisely measured by CMR and predicts outcome in aortic stenosis. Its measurement by CMR is more reproducible than that by TTE and may facilitate left ventricular structure–function analysis
Development of complex executive function over childhood : Longitudinal growth curve modeling of performance on the Groton Maze Learning Task
Abstract This longitudinal study modeled children's complex executive function (EF) development using the Groton Maze Learning Task (GMLT). Using a cohort-sequential design, 147 children (61 males, 5.5–11 years) were recruited from six multicultural primary schools in Melbourne and Perth, Australia. Race/ethnicity data were not available. Children were assessed on the GMLT at 6-month intervals over 2-years between 2010 and 2012. Growth curve models describe age-related change from 5.5 to 12.5 years old. Results showed a quadratic growth trajectory on each measure of error—that is, those that reflect visuospatial memory, executive control (or the ability to apply rules for action), and complex EF. The ability to apply rules for action, while a rate-limiting factor in complex EF, develops rapidly over early-to-mid childhood
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