Seasonal changes in multiple indices of body composition in professional football players.

We examined the seasonal variability of indicators of adiposity and generic and population-specific equations of estimating body fat in professional football players. Anthropometric data of 35 outfield players (age, 20±4 years; stature, 1.82±0.06 m; body mass 77.1±7.3 kg) were collected over a playing season. There were a significant main effects for time for all indicators (p<0.001). Post hoc analysis revealed significant changes in body composition between July and mid-August (∑4SF-DW: 1.6 mm, p<0.001; ∑4SF-R: 2.4 mm, p=0.002; ∑5SF: 2.0 mm, p<0.002; ∑8SF: 3.8 mm, p=0.001; Reilly et al.: 0.4%, p=0.001; Durnin and Wormsley: 0.7%, p<0.001). Although all indicators were sensitive to detect small changes in body composition between training mesocycles, we advocate the use of the sum of 4 skinfolds by Reilly et al. to monitor changes in body composition in professional football players; if an estimate of percent body fat is required, the population-specific equation by Reilly et al. may be utilised.

'Nordic' hamstrings exercise - engagement characteristics and training responses.

The present study examined the neuromuscular activation characteristics of the hamstrings during the 'Nordic' hamstrings exercise (NHE) and changes in the eccentric strength of the knee flexors with NHE training. Initially, the normalised root mean square electromyographic (EMG) activity of the hamstrings of both limbs during various phases (90-61°, 60-31° and 30-0° of knee extension) of the NHE were determined in 18 soccer players. Subsequently participants were randomly allocated to either a training (n=10) or control group. The isokinetic eccentric peak torques of the dominant and non-dominant limbs were recorded at 60, 120 and 240°/s pre- and post-training. The EMG values of both limbs were comparable (P=0.184) and greater EMG activity was recorded at more extended knee positions of the NHE (P=0.001). 4 weeks of NHE training significantly improved peak torque by up to 21% in all assessment conditions. Data indicate the hamstrings of both limbs are engaged identically during the NHE and training results in gains in the eccentric peak torque of the hamstrings of both limbs; these gains may augment the force that the hamstrings can withstand when forcefully stretched, attenuating injury risk.

The epidemiology of malaria in the Papua New Guinea highlands: 7. Southern Highlands Province

As the last part of a program to survey the extent of malaria transmission in the Papua New Guinea highlands, a series of rapid malaria surveys were conducted in 2003-2004 and 2005 in different parts of Southern Highlands Province. Malaria was found to be highly endemic in Lake Kutubu (prevalence rate (PR): 17-33%), moderate to highly endemic in Erave (PR: 10-31%) and moderately endemic in low-lying parts (< 1500 m) of Poroma and Kagua (PR: 12-17%), but was rare or absent elsewhere. A reported malaria epidemic prior to the 2004 surveys could be confirmed for the Poroma (PR: 26%) but not for the lower Kagua area. In Kutubu/Erave Plasmodium falciparum was the most common cause of infection (42%), followed by P. vivax (39%) and P. malariae (16%). In other areas most infections were due to P. vivax (63%). Most infections were of low density (72% < 500/ microl) and not associated with febrile illness. Overall, malaria was only a significant source of febrile illness when prevalence rates rose above 10%, or in epidemics. However, concurrent parasitaemia led to a significant reduction in haemoglobin (Hb) level (1.2 g/dl, CI95: [1.1-1.4.], p < 0.001) and population mean Hb levels were strongly correlated with overall prevalence of malarial infections (r = -0.79, p < 0.001). Based on the survey results, areas of different malaria epidemiology are delineated and options for control in each area are discussed.

Cross-sectional investigation of indices of isokinetic leg strength in youth soccer players and untrained individuals.

In this cross-sectional study, the differences in the isokinetic peak torque of the knee joint muscles (dominant and non-dominant) were investigated in three groups of youths (n=45; age, 14.9+/-1.1 years) with different soccer training backgrounds. Significant main effects were observed for training background on the functional hamstrings to quadriceps ratios for knee flexion (H(CON):Q(ECC) ratio; F(2,42)=4.023, P=0.025) and extension (H(ECC):Q(CON) ratio; F(2,42)=8.53, P<0.001) at 4.32 rad/s. Post hoc tests indicated that both ratios were significantly different between conventionally trained players compared with resistance-trained players and controls (mean+/-SD; H(ECC):Q(CON) ratio, dominant limb; 0.91+/-0.10; 1.04+/-0.12; 1.10+/-0.22; non-dominant limb; 0.89+/-0.09; 1.05+/-0.19; 1.06+/-0.15; H(CON):Q(ECC) ratio, dominant limb; 0.36+/-0.06; 0.34+/-0.07; 0.30+/-0.08; non-dominant limb; 0.33+/-0.05; 0.32+/-0.08; 0.28+/-0.07). Results suggest that the muscle-loading patterns experienced in youth soccer may alter the reciprocal balance of strength about the knee under high-velocity conditions. The findings also indicate that these balances may be improved by incorporating resistance training into the habitual exercise routines of youth soccer players.

Functional gene polymorphisms in canadian aboriginal populations with high rates of tuberculosis.

The present study determined whether a pattern of functional single-nucleotide polymorphisms (SNPs) was present that could predispose a Dené cohort to a suboptimal response to Mycobacterium tuberculosis. Compared with a Caucasian cohort, the Dené and Cree were found to maintain a significantly higher frequency of SNPs associated with low expression of vitamin D receptor (VDR), interferon (IFN)-gamma (+874), and tumor necrosis factor-alpha (-308) and high production of monocyte chemoattractant protein (MCP)-1 (-2518) and interleukin (IL)-6 (-174). Given the roles played by IFN-gamma and VDR in facilitating macrophage containment of M. tuberculosis and the opposing role of MCP-1 and IL-6, the observed allelic variation by ethnicity may in part contribute to the high rates of tuberculosis among the Dené.

Interaction between catechol-O-methyltransferase (COMT) Val108/158Met and brain-derived neurotrophic factor (BDNF) Val66Met polymorphisms in age at onset and clinical symptoms in schizophrenia.

Catechol-O-methyltransferase (COMT) gene is one of the candidate genes for schizophrenia because it codes an enzyme that participates in the metabolic inactivation of dopamine and noradrenaline and a limiting factor of dopamine metabolism in the prefrontal cortex. COMT gene lies on chromosome 22q11.2, which has been associated with schizophrenia susceptibility. A single-nucleotide polymorphism of COMT gene at position 108/158 results in an amino acid substitution from valine (val) to methionine (met), which modifies its enzymatic activity and may change the brain morphology and expressional behaviors. On the other hand, brain-derived neurotrophic factor (BDNF) plays a critical role in the development of mesolimbic dopaminergic- related systems. BDNF also contains a functional single-nucleotide polymorphism at codon 66 (Val66Met) of its prodomain and this polymorphism is responsible for schizophrenia susceptibility. In this study, we first investigated the relationship between COMT Val108/158Met polymorphism and age at onset as well as levels of clinical symptoms in 158 of chronic schizophrenia inpatients and then we investigated the gene-by-gene interaction between COMT Val108/158Met polymorphism and BDNF Val66Met polymorphism with age- and sex-matched control subjects (n = 318). We concluded that the COMT Val108/158Met polymorphism was not related to either the onset at age or the levels of clinical symptoms after long-term antipsychotic treatment in schizophrenia.

A case of Korsakoff's syndrome improved by high doses of donepezil.

We present a case of Korsakoff's syndrome that was successfully treated with high doses of donepezil, an inhibitor of acetylcholine esterase, known to retard the progress of symptoms in Alzheimer's disease. The patient was a 46-year-old married Japanese woman who began to drink alcohol after she married. After several years of drinking she developed typical symptoms of the Korsakoff syndrome. Donepezil was started after treatment with thiamine or thiamine plus fluvoxamine had failed. Her amnestic symptoms as well as her quality of life improved markedly during donepezil treatment. Inhibition of acetylcholine esterase may be an effective treatment for Korsakoff's syndrome.