A growth curve to model changes in sport participation in adolescent boys

The aims of this study are twofold: (1) to present the latent growth model, its strategy and usefulness in modelling sport participation over a 6‐year period in youngsters (2) and to study the impact of biological maturation in sport participation changes. A standardized sport participation questionnaire using h/week/year as the unit of analysis was applied to 588 Belgium boys 13–18 years of age followed longitudinally for 6 years. Skeletal age was used to estimate biological maturation. Growth curve modelling with robust estimation was used. Sport participation changes showed a curvilinear trend: baseline values (3.18±0.13 h/week/year), a linear trend that indicates the rate of change (0.70±0.11) and a quadratic trend indicating deceleration, i.e. a change in the rate of change (?0.07±0.02) were all statistically significant (P<0.05), as well as inter‐individual differences in these three parameters. Up to 16.8 years, the rate of sports participation increased 0.70 h/week/year and then declined. Biological maturation did not show any association with adolescent changes in sport participation.     

Biodistribution and kinetics of radiolabeled proteins in rats with focal infection.

The purpose of this study was to evaluate the role of both protein and radionuclide in the accumulation of 111In-labeled human immunoglobulin G (IgG) in infectious foci. In rats with a calf muscle infection, biodistribution was determined 2, 6, 24, and 48 hr after injection of a radiopharmaceutical. For IgG, human serum albumin (HSA) and human immunoglobulin A (IgA), all labeled with 111In, target-to-background (T/B) ratios were similar throughout the study. However, absolute abscess uptake of 111In-IgA was significantly lower. For IgG labeled with 111In, 123I, or 99mTc, similar T/B ratios were found up to 24 hr. After 48 hr, the T/B ratio of 111In-IgG was significantly higher than the T/B ratio of 123I-IgG. The absolute abscess uptake of 111In-IgG was higher than that of 99mTc-IgG at 24 hr and 123I-IgG at 48 hr. In conclusion, the radionuclide appears to be of major importance in the accumulation of radiolabeled proteins in infectious foci. Protein mainly influences blood clearance and distribution in organs. The Fc-gamma receptor is not crucial for accumulation in infectious foci.     

Resolution of massive technetium-99m methylene diphosphonate uptake in the stomach in vitamin D intoxication

Vitamin D intoxication, which may result from zealous intake of health food supplements, may cause metastatic calcification. This is the first reported case of a patient with vitamin D intoxication who had massive gastric uptake of [99mTc]MDP, but no lung uptake, with histologic documentation of the metastatic calcification by gastric biopsy. It is probable that the metastatic calcification was a highly metabolic process in this patient since the gastric uptake resolved within 3 wk when serum calcium and phosphate had returned to normal.     

Inheritance of static and dynamic arm strength and some of its determinants

Maximal static, eccentric and concentric torques and arm components estimated by anthropometry and measured by computed tomography were evaluated in 25 male monozygotic twins and 16 dizygotic twins (22.4 ± 3.7 years). The importance of genetic and environmental factors in the observed variation in these measurements was estimated by genetic model-fitting techniques. In this sample of young adult male twins, genetic factors were significant in most of the strength measurements, arm muscle components and muscle activation variables. The contribution of genetic factors in strength measures depended on the angle, contraction type and to some extent on contraction velocity. For isometric strength, angle-specificity in genetic and environmental variation could be attributed to the degree of variability in muscle activation and performance discomfort at each specific angle, with the highest unique environmental impact at extreme angles. The high genetic contribution at 170°, but not at 50°, possibly expressed different contributions of genetic factors in the muscle-length factor and moment arm in torques at both angles. The importance of genetic factors in eccentric arm flexor strength (62–82%) was larger than for concentric flexion (29–65%), as the pattern of genetic determination followed the torque-velocity curve. Genetic variations in contractile and elastic components, contributing differently to eccentric and concentric torques, together with velocity-dependent actin-myosin binding factors, could account for the observed differences. The broad heritability was very high for all anthropometric and arm cross-sectional area measurements (>85%) and common environmental factors were only significant for anthropometrically estimated mid-arm muscle tissue area (48%). Heritability estimates of different arm muscularity measurements were comparable.     

Intravascular large B-cell lymphoma with bone marrow involvement at presentation and haemophagocytic syndrome: two Western cases in favour of a specific variant

AIMS: To report two cases of an unusual form of intravascular lymphoma, characterized by bone marrow involvement at presentation with haemophagocytic syndrome. METHODS AND RESULTS: We describe the clinicopathological features of two patients with intravascular lymphoma primarily involving bone marrow. Both patients complained only of fever with pancytopenia and reactive haemophagocytic syndrome. Diagnosis was made on bone marrow examination, which showed large tumour cells of B-cell lineage confined within the lumen of sinuses. CONCLUSION: These two cases and five previous reports could represent a variant of intravascular lymphoma, characterized by early involvement of bone marrow without dissemination to other organs. This form of intravascular lymphoma, called IVL-HS, seems to be an 'Asian' variant with a high prevalence in Asian people and a very low prevalence in Western countries. At a practical level, bone marrow biopsy may be useful in the diagnosis of intravascular lymphoma when the clinical presentation is restricted to fever of unknown origin with a reactive haemophagocytic syndrome.     

Associations between daily physical activity and physical fitness in Flemish males: A cross-sectional analysis

The relationship of physical activity to several components of physical fitness was investigated in a sample of 166 males 40 years of age. In addition to Pearson correlations, multivariate canonical correlations were calculated. Physical activity during work (work index), sport (sport index), and leisure time (leisure time index) was assessed by the Baecke questionnaire. Physical fitness included cardiorespiratory fitness measures, the body mass index (BMI), the sum of seven skinfold thicknesses (SKI), percentage body fat (PFAT), balance, and several tests of muscle strength and endurance, flexibility, and speed of limb movement. More than 86% of the variance was shared by the two first canonical variables. The first canonical variable can be interpreted as a health-related fitness function. Carciorespiratory fitness, balance, speed of limb movement, explosive strength, and trunk muscle strength are clearly related to this function. From the physical activity measures, the Baecke sport index correlated significantly with this health-related fitness function. The second canonical variable can be explained as a fatness function, since body weight, BMI, SKI, and PFAT showed the highest correlations with the variable. The Baecke work index was inversely related to this canonical variable. The sample was also divided into physical activity groups in order to look for differences in physical fitness. The data indicate that physical activity during work was modestly, but inversely related to adiposity. Sport activity was beneficially associated to several fitness components, including cardiorespiratory fitness, trunk muscle strength, and upper body muscular endurance. Am. J. Hum. Biol. 11:587–597, 1999. © 1999 Wiley-Liss, Inc.     

Skeletal maturity and socio-economic status in Portuguese children and youths: the Madeira growth study

Background: Skeletal maturity is used to evaluate biological maturity status. Information about the association between socio-economic status (SES) and skeletal maturity is limited in Portugal.

Aims: The aim of this study is to document the skeletal maturity of youths in Madeira and to evaluate variation in maturity associated with SES.

Subjects and methods: The study involved 507 subjects (256 boys and 251 girls) from the Madeira Growth Study, a mixed-longitudinal study of five cohorts (8, 10, 12, 14 and 16 years of age) followed at yearly intervals over 3 years (1996–1998). A total of 1493 observations were made. Skeletal age was estimated from radiographs of the hand and wrist using the Tanner–Whitehouse 2 method (TW2). Social class rankings were based on Graffar's (1956) method. Five social rankings were subsequently grouped into three SES categories: high, average and low.

Results: Median for the radius, ulna and short finger bones (RUS scores) in the total sample of boys and girls increased curvilinearly across age whereas median for the 7 (without pisiform) carpal bones (Carpal scores) increased almost linearly. The 20-bone maturity scores demonstrated distinctive trends by gender: the medians for boys increased almost linearly while the medians for girls increased curvilinearly. SES differences were minimal. Only among children aged 10–11 years were high SES boys and girls advanced in skeletal maturity. Madeira adolescents were advanced in skeletal maturity compared with Belgian reference values.

Conclusion: The data suggests population variation in TW2 estimates of skeletal maturation. Skeletal maturity was not related to SES in youths from Madeira.     

Blood pressure waveform analysis by means of wavelet transform

The assessment of cardiovascular function by means of arterial pulse wave analysis (PWA) is well established in clinical practice. PWA is applied to study risk stratification in hypertension, with emphasis on the measurement of the augmentation index as a measure of aortic pressure wave reflections. Despite the fact that the prognostic power of PWA, in its current form, still remains to be demonstrated in the general population, there is general agreement that analysis and interpretation of the waveform might provide a deeper insight in cardiovascular pathophysiology. We propose here the use of wavelet analysis (WA) as a tool to quantify arterial pressure waveform features, with a twofold aim. First, we discuss a specific use of wavelet transform in the study of pressure waveform morphology, and its potential role in ascertaining the dynamics of temporal properties of arterial pressure waveforms. Second, we apply WA to evaluate a database of carotid artery pressure waveforms of healthy middle-aged women and men. Wavelet analysis has the potential to extract specific features (wavelet details), related to wave reflection and aortic valve closure, from a measured waveform. Analysis showed that the fifth detail, one of the waveform features extracted applying the wavelet decomposition, appeared to be the most appropriate for the analysis of carotid artery pressure waveforms. What remains to be assessed is how the information embedded in this detail can be further processed and transformed into quantitative data, and how it can be rendered useful for automated waveform classification and arterial function parameters with potential clinical applications.     

Nutritional Intake,White Matter Integrity,and Neurodevelopment in Extremely Preterm Born Infants

Background: Determining optimal nutritional regimens in extremely preterm infants remains challenging. This study aimed to evaluate the effect of a new nutritional regimen and individual macronutrient intake on white matter integrity and neurodevelopmental outcome. Methods: Two retrospective cohorts of extremely preterm infants (gestational age < 28 weeks) were included. Cohort B (n = 79) received a new nutritional regimen, with more rapidly increased, higher protein intake compared to cohort A (n = 99). Individual protein, lipid, and caloric intakes were calculated for the first 28 postnatal days. Diffusion tensor imaging was performed at term-equivalent age, and cognitive and motor development were evaluated at 2 years corrected age (CA) (Bayley-III-NL) and 5.9 years chronological age (WPPSI-III-NL, MABC-2-NL). Results: Compared to cohort A, infants in cohort B had significantly higher protein intake (3.4 g/kg/day vs. 2.7 g/kg/day) and higher fractional anisotropy (FA) in several white matter tracts but lower motor scores at 2 years CA (mean (SD) 103 (12) vs. 109 (12)). Higher protein intake was associated with higher FA and lower motor scores at 2 years CA (B = −6.7, p = 0.001). However, motor scores at 2 years CA were still within the normal range and differences were not sustained at 5.9 years. There were no significant associations with lipid or caloric intake. Conclusion: In extremely preterm born infants, postnatal protein intake seems important for white matter development but does not necessarily improve long-term cognitive and motor development.