Anthropometric data of outstanding gymnasts were gathered on the occasion of the 24th World Championship Artistic Gymnastics, held at Rotterdam, The Netherlands, in October 1987. In total 165 males ...and 201 females were investigated, constituting 84% of the total number of participants. The data of these gymnasts were descriptively compared with both reference data and data reported in previous studies on gymnasts competing at international events. Also, based on the data obtained, 'gymnastic-specific' anthropometric reference values (i.e. profile charts), were established for both male and female gymnasts. Finally, the maturational characteristics (skeletal age and menarche) of the 'Rotterdam' female gymnasts were described.
The aim of this study was to establish differences in intra-cyclic horizontal velocity variation of the body's centre of mass in breaststroke swimmers with flat and undulating styles. Vertical ...eel-like body waving and trunk rotations were measured to distinguish styles. To reconstruct trunk extension and kyphosis in the poorly visible zone close to the water surface, a semi-automated video-analysis system was developed. From 45 internationallevel swimmers examined, two groups of women and two groups of men were identified, those using the most undulating and those using the flattest styles. Among the men with the flattest style, the maximum and minimum horizontal velocity of the body's centre of mass differed by 76% from the mean swimming velocity; among the women with the most undulating style, the figure was 53%. In the most undulating style, less horizontal velocity variation of the body's centre of mass could be explained by movements of the body parts above the water surface, creating a transfer of momentum: a quick backward upper trunk rotation generates resistance and a quick forward shoulder girdle and upper arm movement, followed by a quick forward upper trunk and head rotation, generates propulsion. In addition, during an upward leg kick, some swimmers generated propulsion similar to that seen in eels.
The growth and maturity status of 201 elite female gymnasts was considered. The subjects were participants at the 24 World Championship Artistic Gymnastics in 1987. In addition to age at menarche, ...weight, stature, biacromial, and bicristal breadths, the sitting height/stature ratio, and the Health-Carter anthropometric somatotype of gymnasts 13-20 yr of age were compared with reference data for a nationally representative sample of Flemish girls. Median age at menarche (probit analysis) in gymnasts is 15.6 +/- 2.1 yr compared with 13.2 +/- 1.2 yr in Flemish girls. Anthropometric dimensions increase with age until about 16 yr and then tend to plateau. In contrast to body size, there is little variation in somatotype with age. Compared with adolescent girls, elite gymnasts are considerably shorter and lighter with narrower shoulders and hips, but the differences are more apparent after 17 yr. Elite gymnasts do not differ from nonathletes in relative leg length, but they have proportionally broader shoulders relative to hips. Differences in somatotype occur primarily in endomorphy (especially lower in gymnasts) and to a lesser extent in mesomorphy (higher in gymnasts).
The basic principles underlying the design of a velocimeter based on an unwinding wire, for use in athletics research, are discussed. It is shown by theoretical analysis that, in order to avoid ...runaway effects, the tension on the wire should be either high or low but not of intermediate strength. The low tension regime is shown to be theoretically the most favourable as it combines high accuracy of speed measurements in decelerated motion with insensitivity to resonance oscillations of the wire. Practical considerations concerning the ruggedness of the apparatus, however, favour the high tension regime. A modern apparatus incorporating microprocessors and working with thin nylon wire stretched by a force of the order of 1 N, i.e. in the high tension regime, has been constructed and tested. The test results show that the velocity of decelerated motions (up to decelerations of the order of 10 m s-2) can be faithfully recorded in the velocity range 0-15 m s-1. The relative error for the measurement of constant speed up to 15 m s-1 is about one in a thousand, which is very small and practically unattainable by other methods. An application to the study of the long jump is demonstrated and validated by the use of film analysis.
Abstract Background There is no consensus on the width of tumour-free margins after surgery for vulvar squamous cell carcinoma (VSCC). Most current guidelines recommend tumour-free margins of ≥8 mm. ...The aim of this study was to investigate whether a margin of <8 mm is associated with an increased risk of local recurrence in VSCC. Methods A meta-analysis of the available literature and a cohort study of 148 VSCC patients seen at a referral centre from 2000 to 2012 was performed. The primary end-point of the cohort study was a histologically confirmed ipsilateral local recurrence within 2 years after primary treatment in relation to the margin distance. Results Based on 10 studies, the meta-analysis showed that a tumour-free margin of <8 mm is associated with a higher risk of local recurrence compared to a tumour-free margin of ≥8 mm (pooled risk ratio, 1.99 95% confidence interval {CI}: 1.13–3.51, p = 0.02). In the cohort study, we found no clear difference in the risk of local recurrence in the <8 versus ≥8 mm group; however, 40% of the patients in the <8 mm group received additional treatment. Tumour-positive margin was the only independent risk factor for local recurrence in the multivariable analysis (hazard ratio, 0.21 95% CI: 0.08–0.55). Conclusions This work provides important data to question the commonly used 8-mm margin as a prognosticator for local recurrence. More research is needed to address the question of whether additional treatment improves the prognosis in patients with a tumour-free margin of <8 mm.
Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ZonMW
Introduction
Cardiovascular diseases (CVD) are the leading cause of ...death globally. The CVD that causes most of the deaths annually is atherosclerosis 1. The treatment of choice for acute symptoms like myocardial infarction is percutaneous coronary intervention with the implantation of a stent. Despite successful clinical results, there are still complications 2. Current pre-clinical research to assess safety and efficacy of stents is primarily based on healthy animal models 3. However, these are limited to the number of simultaneous experiments and ethical concerns. Several in-vitro and ex-vivo models are available to evaluate and assess medical devices and treatments. In particular, ex-vivo systems represent an important class, because the presence of native tissue guarantees biological response as a result of cell-cell interaction within a physiological extracellular matrix.
Purpose
The main goal of this research is to culture coronary arteries long-term in order to maintain them viable for assessment of safety and efficacy of stents, by mimicking physiological conditions.
Methods
The ex-vivo vascular bioreactor was used and data were acquired as described before 4. Culture experiments were performed on porcine right coronary arteries (RCA) (n=9). Duration of culture was set to 2 (n=3), 4 (n=3), and 9 days (n=3). Hearts harvested from a local slaughterhouse were kept on Krebs-buffer (4°C) until dissection within 2 hours. The bioreactor containing the dissected RCA was placed in a 38°C incubator with 100% humidity and 5% CO2. The RCA was cultured in a blood-mimicking culture medium 4. To assess cultured blood vessel morphology, diameter and structure during the culture period, ultrasound imaging was performed. Pressure (60-100 mmHg), flow rate (± 60 ml/min), and diameter measurements were monitored every day. The flow rate was adjusted to ensure a physiological peak endothelial shear stress of around 0.8 – 1.8 Pa. After 2, 4 or 9 days of culture, the RCA was fixed in buffered formaldehyde for 24 hours, embedded in paraffin and sectioned. Histology was performed using hematoxylin and eosin (H&E) and resorcin fuchsin (RF).
Results
Ultrasound imaging showed that the morphology and structure of cultured arteries was maintained during the cultures (average diameter 3.5±1.1 mm). Extracellular matrix was preserved as shown by histology (RF stain, Figure 1). Endothelial cells (ECs) coverage was incomplete at 2, but after 4 days it was completely restored. After 9 days of culture, a minimal layer of newly formed neointima was visible (Figure 1).
Conclusions
The cultured RCAs maintained their physiological morphology up to 9 days of culture. The endothelium was completely restored after 4 days, making the system suitable for ex-vivo interventions like stenting. The investigated model represents a useful tool for testing vascular therapies and devices, supporting the translational phase between in-vitro and ex-vivo studies.
The evidence that inflammation is an important pathway in age-related macular degeneration (AMD) is growing. Recent case-control studies demonstrated an association between the complement factor H ...(CFH) gene, a regulator of complement, and AMD.
To assess the associations between the CFH gene and AMD in the general population and to investigate the modifying effect of smoking, serum inflammatory markers, and genetic variation of C-reactive protein (CRP).
Population-based, prospective cohort study of individuals aged 55 years or older (enrollment between March 20, 1990, and July 31, 1993, and 3 follow-up examinations that were performed between September 1, 1993, and December 31, 2004) in Rotterdam, the Netherlands. The CFH Y402H polymorphism was determined in a total of 5681 individuals. Information on smoking, erythrocyte sedimentation rate, CRP serum levels, and haplotypes of the CRP gene were assessed at baseline.
All severity stages of prevalent and incident AMD, graded according to the international classification and grading system for AMD.
The frequency of CFH Y402H was 36.2% (4116/11,362 alleles). At baseline, there were 2062 persons (36.3%) with any type of AMD (prevalent cases), including 78 (1.4%) with late AMD (stage 4). During follow-up (mean, 8 years; median, 10 years), 1649 (35.5%) of 4642 participants progressed to a higher stage of AMD (incident cases), including 93 (5.6%) who developed late AMD. The odds ratio (OR) of AMD increased in an allele-dose manner with 2.00 (95% confidence interval CI, 1.56-2.55) for stage 2 AMD, 4.58 (95% CI, 2.82-7.44) for stage 3 AMD, and 11.02 (95% CI, 6.82-11.81) for stage 4 (late, vision threatening) AMD for homozygous persons. Cumulative risks calculated by Kaplan-Meier analysis of late AMD by age 95 years were 48.3% for homozygotes, 42.6% for heterozygotes, and 21.9% for noncarriers. The population-attributable risk for CFH Y402H was 54.0%. Elevated erythrocyte sedimentation rates further increased the OR to 20.2 (95% CI, 9.5-43.0), elevated serum CRP levels to 27.7 (95% CI, 10.7-72.0), and smoking to 34.0 (95% CI, 13.0-88.6) for homozygotes compared with noncarriers without these determinants. The CRP haplotypes conferring high levels of CRP significantly increased the effect of CFH Y402H (P<.01).
The CFH Y402H polymorphism may account for a substantial proportion of AMD in individuals similar to those in the Rotterdam Study and may confer particular risk in the presence of environmental and genetic stimulators of the complement cascade.
Recent randomized trials have proven the benefit of intra-arterial treatment (IAT) with retrievable stents in acute ischemic stroke. Patients with poor or absent collaterals (preexistent anastomoses ...to maintain blood flow in case of a primary vessel occlusion) may gain less clinical benefit from IAT. In this post hoc analysis, we aimed to assess whether the effect of IAT was modified by collateral status on baseline computed tomographic angiography in the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN).
MR CLEAN was a multicenter, randomized trial of IAT versus no IAT. Primary outcome was the modified Rankin Scale at 90 days. The primary effect parameter was the adjusted common odds ratio for a shift in direction of a better outcome on the modified Rankin Scale. Collaterals were graded from 0 (absent) to 3 (good). We used multivariable ordinal logistic regression analysis with interaction terms to estimate treatment effect modification by collateral status.
We found a significant modification of treatment effect by collaterals (P=0.038). The strongest benefit (adjusted common odds ratio 3.2 95% confidence intervals 1.7-6.2) was found in patients with good collaterals (grade 3). The adjusted common odds ratio was 1.6 95% confidence intervals 1.0-2.7 for moderate collaterals (grade 2), 1.2 95% confidence intervals 0.7-2.3 for poor collaterals (grade 1), and 1.0 95% confidence intervals 0.1-8.7 for patients with absent collaterals (grade 0).
In MR CLEAN, baseline computed tomographic angiography collateral status modified the treatment effect. The benefit of IAT was greatest in patients with good collaterals on baseline computed tomographic angiography. Treatment benefit appeared less and may be absent in patients with absent or poor collaterals.
URL: http://www.trialregister.nl and http://www.controlled-trials.com. Unique identifier: (NTR)1804 and ISRCTN10888758, respectively.
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