Rationale and design of the Measuring Athlete’s Risk of Cardiovascular events (MARC) study: The role of coronary CT in the cardiovascular evaluation of middle-aged sportsmen

BackgroundMore than 90 % of exercise-related cardiac arrests occur in men, predominantly those aged 45 years and older with coronary artery disease (CAD) as the main cause. The current sports medical evaluation (SME) of middle-aged recreational athletes consists of a medical history, physical examination, and resting and exercise electrocardiography. Coronary CT (CCT) provides a minimally invasive low radiation dose opportunity to image the coronary arteries. We present the study protocol of the Measuring Athlete’s Risk of Cardiovascular events (MARC) study. MARC aims to assess the additional value of CCT to a routine SME in asymptomatic sportsmen ≥45 years without known CAD.DesignMARC is a prospective study of 300 asymptomatic sportsmen ≥45 years who will undergo CCT if the SME does not reveal any cardiac abnormalities. The prevalence and determinants of CAD (coronary artery calcium score ≥100 Agatston Units (AU) or ≥50 % luminal stenosis) will be reported. The number needed to screen to prevent the occurrence of one cardiovascular event in the next 5 years, conditional to adequate treatment, will be estimated.DiscussionWe aim to determine the prevalence and severity of CAD and the additional value of CCT in asymptomatic middle-aged (≥45 years) sportsmen whose routine SME revealed no cardiac abnormalities.

Electronic supplementary material

The online version of this article (doi:10.1007/s12471-014-0630-0) contains supplementary material, which is available to authorized users.     

Hydrochemical,bacteriological assessment,and classification of groundwater quality in Thulamela Municipality,South Africa: potential health risk

Abstract

Potential effects of anthropogenic activities on different boreholes around Thulamela Municipality, South Africa, were evaluated by quantifying the bacteria indicators and physicochemical parameters during summer, autumn, and winter. The purpose was to determine whether the borehole water in this region is safe for domestic use across the seasons. The concentrations of physicochemical (Temperature, pH, electrical conductivity (EC), turbidity, and nitrate) and bacteriological (both Escherichia coli and Enterococcus faecalis) contaminants in the borehole water samples were determined using standard microbiology methods. The mean concentration of NO₃ for most of the boreholes failed to comply with the recommended guidelines throughout the season. High microbial load of E. coli (2.0?×?10¹ – 4.6?×?10³ CFU/100?ml) and E. faecalis (2.0?×?10° – 6.0?×?10² CFU/100?ml) was recorded in the wet season than in the dry season (0.0 – 7.0?×?10² and 0.0 – 1.0?×?10¹ CFU/100?ml, respectively). Sanitary inspection and water source classification showed that most boreholes are prone to chemical contaminants during summer and autumn due to rainfall and this correlates with the measured microbial contamination. The result is significantly important because water from these boreholes is used for domestic purposes without treatment and could pose major public health risks to the consumers.     

Performance assessment of a new optimization system for robotic SBRT MLC-based plans

PurposeTo assess the performance of a new optimization system, VOLO, for CyberKnife MLC-based SBRT plans in comparison with the existing Sequential optimizer.MethodsMLC-plans were created for 25 SBRT cases (liver, prostate, pancreas and spine) using both VOLO and Sequential. Monitor units (MU), delivery time (DT), PTV coverage, conformity (nCI), dose gradient (R50%) and OAR doses were used for comparison and combined to obtain a mathematical score (MS) of plan quality for each solution. MS strength was validated by changing parameter weights and by a blinded clinical plan evaluation. The optimization times (OT) and the average segment areas (SA) were also compared.ResultsVOLO solutions offered significantly lower mean DT (−19%) and MU (−13%). OT were below 15 min for VOLO, whereas for Sequential, values spanned from 8 to 160 min. SAs were significantly larger for VOLO: on average 10 cm² versus 7 cm². VOLO optimized plans achieved a higher MS than Sequential for all tested parameter combinations. PTV coverage and OAR sparing were comparable for both groups of solutions. Although slight differences in R50% and nCI were found, the parameters most affecting MS were MU and DT. VOLO solutions were selected in 80% of cases by both physicians with 88% inter-observer agreement.ConclusionsThe good performance of the VOLO optimization system, together with the large reduction in OT, make it a useful tool to improve the efficiency of CK SBRT planning and delivery. The proposed methodology for comparing different planning solutions can be applied in other contexts.     

Linkage studies on erythrocyte antigen loci, the major histocompatibility complex and the haemoglobin beta gene cluster in goats

Linkage studies on seven erythrocyte antigen loci, the major histocompatibility complex (MHC) and the haemoglobin beta gene cluster (HBB) were performed in 48 Norwegian goat families. Close linkage was excluded between the erythrocyte antigen B-system and the MHC, between the erythrocyte antigen N7 locus and HBB, and between the MHC and the HBB.