12 research outputs found
Changes in Vitamin D Status in Overweight Middle-Aged Adults with or without Impaired Glucose Metabolism in Two Consecutive Nordic Summers
Effects of Oral Contraceptives on Body Composition and Physical Performance in Female Athletes
Does individual learning styles influence the choice to use a web-based ECG learning programme in a blended learning setting?
<p>Abstract</p> <p>Background</p> <p>The compressed curriculum in modern knowledge-intensive medicine demands useful tools to achieve approved learning aims in a limited space of time. Web-based learning can be used in different ways to enhance learning. Little is however known regarding its optimal utilisation. Our aim was to investigate if the individual learning styles of medical students influence the choice to use a web-based ECG learning programme in a blended learning setting.</p> <p>Methods</p> <p>The programme, with three types of modules (learning content, self-assessment questions and interactive ECG interpretation training), was offered on a voluntary basis during a face to face ECG learning course for undergraduate medical students. The Index of Learning Styles (ILS) and a general questionnaire including questions about computer and Internet usage, preferred future speciality and prior experience of E-learning were used to explore different factors related to the choice of using the programme or not.</p> <p>Results</p> <p>93 (76%) out of 123 students answered the ILS instrument and 91 the general questionnaire. 55 students (59%) were defined as users of the web-based ECG-interpretation programme. Cronbach's alpha was analysed with coefficients above 0.7 in all of the four dimensions of ILS. There were no significant differences with regard to learning styles, as assessed by ILS, between the user and non-user groups; Active/Reflective; Visual/Verbal; Sensing/Intuitive; and Sequential/Global (p = 0.56-0.96). Neither did gender, prior experience of E-learning or preference for future speciality differ between groups.</p> <p>Conclusion</p> <p>Among medical students, neither learning styles according to ILS, nor a number of other characteristics seem to influence the choice to use a web-based ECG programme. This finding was consistent also when the usage of the different modules in the programme were considered. Thus, the findings suggest that web-based learning may attract a broad variety of medical students.</p
Hormonal mechanisms of menstrual disturbances, metabolic disorders and effects of oral contraceptives in female athletes
Background: During the last decades the number of women participating in
sports has increased dramatically. Although exercise has beneficial
health effects for most of these women, we now realize that strenuous
exercise may also have serious medical consequences. Menstrual
dysfunction is common among athletes and the exact mechanisms are not
known. The metabolic consequences of long-standing amenorrhea are serious
including increased bone resorption and possibly deleterious effects on
the cardiovascular system. Oral contraceptives (OCs) are often used for
treatment of estrogen deficiency but there are no studies evaluating the
effects of this treatment in athletes. The aims of this work were to
study mechanisms of menstrual disturbances and associated metabolic
disorders in endurance athletes. Furthermore, to evaluate effects of OCs
on bone mineral density (BMD), endothelial function and physical
performance in athletes.
Methods: Age- and body mass index-matched groups of endurance athletes
with menstrual disturbance, regularly cycling athletes and sedentary
controls, all together 51 subjects, were examined before and after -10
months of treatment with a low-dose, monophasic, combined OC. Baseline
hormonal status and diurnal profiles of pituitary hormones and steroid
hormones were investigated. Body composition including BMD was examined
by dual energy X-ray absorptiometry and physical performance was
evaluated by endurance and strength tests. Blood lipids were analyzed and
endothelial function was studied by ultrasound assessment of
flow-mediated vasodilatation (FMD).
Results: The majority of athletes with menstrual disturbance had a
hormonal profile in accordance with hypothalamic inhibition of the
reproductive system including decreased diurnal LH-pulsatility and peak
amplitude of prolactin and increased diurnal secretion of cortisol and
growth hormone. This group of athletes had the lowest fat mass and BMD
among all groups. In addition, we identified a hyperandrogenic subgroup
of athletes with menstrual disturbance, having increased diurnal
secretion of testosterone, increased LH/FSH ratio and decreased serum
levels of SHBG. This subgroup had an anabolic body composition with the
highest total BMD and lean body mass among the groups. The
hyperandrogenic subgroup also had the highest V02max and the highest
performance values in general. Athletes with amenorrhea had impaired
endothelial function and an unfavorable lipid profile, whereas
oligomenorrheic athletes had the most favorable lipid profile and an
intermediate FMD. OC treatment caused a significant change in weight and
fat mass only in the athlete group with menstrual disturbance. OC
treatment also increased BMD in athletes with the largest increase in
those with a low BMD at baseline. Despite significant changes in body
composition, only a small impact on physical performance was recorded
during OC. Endothelial dysfunction in amenorrheic athletes was improved
by OC treatment.
Conclusions: Menstrual disturbances in female athletes are often
explained as a consequence of hypothalamic inhibition due to energy
deficiency. This thesis suggests essential hyperandrogenism, such as
polycystic ovary syndrome as an alternative mechanism underlying
menstrual disturbance in athletes, especially oligomenorrhea. This
condition may imply an advantage for physical performance. Amenorrhea in
athletes is associated with endothelial dysfunction and an unfavorable
lipid profile. OC treatment has predominantly beneficial effects on body
composition, BMD and endothelial function without adverse effects on
physical performance and could be used for prevention of osteoporosis in
athletic amenorrhea
Effects of oral contraceptives on body composition and physical performance in female athletes.
Menstrual disturbances are common among female athletes, and oral contraceptives (OCs) are often recommended as estrogen substitution. However, there is little information about the effects of OC use in athletes, and there is great concern that OCs might impair physical performance. The aim of this study was to investigate the effects of OC use on body composition and physical performance in female athletes. Twenty-six endurance athletes (13 with oligo-/amenorrhea and 13 regularly menstruating athletes) and 12 sedentary controls were examined before and after 10 months of treatment with a low dose, monophasic, combined OC. Significant changes in body composition were recorded in the athletes, but not in the controls. There was an increase in weight and fat mass only in athletes with oligo-/amenorrhea. These changes were associated with a decrease in ovarian androgens. OC treatment also increased bone mineral density, with the largest increase in athletes with a low bone mineral density at baseline. Despite significant changes in body composition, little impact on physical performance was recorded. We have demonstrated that OC treatment in female athletes has predominantly beneficial effects on body composition without adverse effects on physical performance and could be used for the prevention of osteoporosis in athletic amenorrhea. However, it cannot be excluded that a marked increase in fat mass might have unfavorable effects for athletic performance in individual women
Intima-media thickness of the descending aorta in patients with bicuspid aortic valve
A bicuspid aortic valve (BAV) is associated with accelerated aortic valve disease (AVD) and abnormalities in aortic elasticity. We investigated the intima-media thickness of the descending aorta (AoIMT) in patients with AVD with or without an ascending aortic aneurysm (AscAA), in relation to BAV versus tricuspid aortic valve (TAV) phenotype, type of valve disease, cardiovascular risk factors, and single-nucleotide polymorphisms (SNPs) with a known association with carotid IMT. 368 patients (210 with BAV, 158 with TAV, ), mean age 64 ± 13 years) were examined using transesophageal echocardiography (TEE) before valvular and/or aortic surgery. No patient had a coronary disease (CAD). The AoIMT was measured on short-axis TEE images of the descending aorta using a semi-automated edge-detection technique. AoIMT was univariately (P < 0.05) related to age, blood pressure, smoking, creatinine, highly sensitive C-reactive protein, HDL, valve hemodynamics and BAV. In the TAV subgroup it was also associated with the rs200991 SNP. Using multivariate regression analysis, age was the main determinant for AoIMT (P < 0.001), followed by male gender (P = 0.02), BAV was no longer a significant predictor of AoIMT. AoIMT was still related to the rs200991 SNP in TAV (P = 0.034), and to creatinine in BAV (P = 0.019), when other variables were accounted for. Intima-media thickness of the descending aorta is not affected by aortic valve morphology (BAV/TAV), age is the main determinant of AoIMT. Genetic markers (SNPs) known to influence IMT in the carotid artery seem to correlate to IMT in the descending aorta only in patients with TAV
Changes in Vitamin D Status in Overweight Middle-Aged Adults with or without Impaired Glucose Metabolism in Two Consecutive Nordic Summers
Intima-media thickness of the descending aorta in patients with bicuspid aortic valve
Objective: A bicuspid aortic valve (BAV) is associated with accelerated aortic valve disease (AVD) and abnormalities in aortic elasticity. We investigated the intima-media thickness of the descending aorta (AoIMT) in patients with AVD with or without an ascending aortic aneurysm (AscAA), in relation to BAV versus tricuspid aortic valve (TAV) phenotype, type of valve disease, cardiovascular risk factors, and single-nucleotide polymorphisms (SNPs) with a known association with carotid IMT.
Methods and results: 368 patients (210 with BAV, 158 with TAV,); mean age 64 ± 13 years) were examined using transesophageal echocardiography (TEE) before valvular and/or aortic surgery. No patient had a coronary disease (CAD). The AoIMT was measured on short-axis TEE images of the descending aorta using a semi-automated edge-detection technique. AoIMT was univariately (P < 0.05) related to age, blood pressure, smoking, creatinine, highly sensitive C-reactive protein, HDL, valve hemodynamics and BAV. In the TAV subgroup it was also associated with the rs200991 SNP. Using multivariate regression analysis, age was the main determinant for AoIMT (P < 0.001), followed by male gender (P = 0.02), BAV was no longer a significant predictor of AoIMT. AoIMT was still related to the rs200991 SNP in TAV (P = 0.034), and to creatinine in BAV (P = 0.019), when other variables were accounted for.
Conclusions: Intima-media thickness of the descending aorta is not affected by aortic valve morphology (BAV/TAV); age is the main determinant of AoIMT. Genetic markers (SNPs) known to influence IMT in the carotid artery seem to correlate to IMT in the descending aorta only in patients with TAV