Revista de medicina deportiva y estudios de dopaje

Objective: The purpose of this study was to investigate the effect of Tai Chi (TC) exercise on immune functions among middle-aged and elderly women, and to evaluate the relationship between immune modulation of Natural Killer T (NKT) cells and Dendritic Cells (DCs) and T Helper (Th) 1 /Th2 immune response.
Methods: Sixty healthy middle-aged and elderly women were randomly assigned into 2 groups: Tai Chi (TC) group (n=30) and control (CON) group (n=30). Subjects in TC group participated in TC exercise for 6 months, 60 minutes a day, four times a week. Meanwhile, subjects in CON group maintained their normal physical activity levels during the whole study period. Peripheral blood samples were collected right before, and after 4 and 6 months of the exercise program, and the sampled were analyzed within 24 hours after collection.
Results: After the 6-month TC exercise program, the percentage of CD4+ T lymphocytes, the CD4+:CD8+ ratio, and the percentage of NK and NKT cells in TC group significantly increased (p<0.05). The percentage of interferon-γ (IFN-γ) producing T cells increased significantly after 4 months (p<0.01) and 6 months (p<0.05) of exercise. The percentage of interleukin-4 (IL-4) producing T lymphocytes also demonstrated an increase after 4 months (p<0.05) and 6 months (p>0.05) of exercise. The percentage of CD123+ DCs and CD11c+ DCs also significantly increased after the 6-month program (p<0.01), with the percentage of CD11c+ cells increasing much more dramatically than CD123+ DCs. However, the CON group did not show any significant changes in these parameters.
Conclusion: Regular TC exercise favors the development of Th1 immune responses in middle-aged and elderly women. TC-induced changes in Th1 and Th2 immune responses are associated with the immune modulation of NKT cells and DCs and their reciprocal interactions.

When athletes use performance enhancing drugs, they violate the nature of sport. With the recent doping scandals in Olympic and professional sport, current deterrence methods do not appear to be effective. Thus it is important to better understand why athletes engage in Performance Enhancing Drug (PED) use. Evidence associating doping with moral disengagement is accumulating and suggests that mechanisms of moral disengagement may play an important role in facilitating doping by allowing athletes to rationalize their PED use. We suggest that a more detailed understanding of moral disengagement could assist in reducing PED use in the future.

Since 2010, the World Anti-Doping Agency (WADA) has introduced urinary thresholds for some beta2-agonists. In doping analysis urine samples of beta2-agonists are not corrected for the Urine Specific Gravity (USG) by the WADA laboratories. Several studies have observed high differences in the urine concentrations of beta2-agonists when correction for USG is compared with no correction, as well as high inter-individual variability between subjects. However, no studies have measured the intra-individual variability after inhalation of the long-acting beta2-agonist salmeterol. As such, the purpose of this study was to measure the intra-individual variability in the urine concentrations of salmeterol and its metabolite α-hydroxysalmeterol. Furthermore, to highlight the variability between corrected and uncorrected urine samples for USG. Urine samples from 20 subjects were analyzed for USG, urine excretion and urine concentrations of salmeterol and α-hydroxysalmeterol. Seven of the subjects underwent a second visit with the same procedures. At each visit 100 μg salmeterol was administered by inhalation. Urine samples were collected before administration of the drug (T0) and 4 (T4), 8 (T8) and 12 (T12) hours after administration. The mean relative differences in the urine concentrations of salmeterol and α-hydroxysalmeterol between USG corrected and uncorrected samples were 43 ± 44, 27 ± 42 and 56 ± 87% at T4, T8 and T12, respectively. The intra-individual variability in the urine excretion of salmeterol and α-hydroxysalmeterol during visits one and two were 12.6 and 21.8%, respectively. The intra-individual variability of salmeterol and α-hydroxysalmeterol in the urine concentrations were significantly
higher when uncorrected for USG with 43.0 and 43.7% versus 20.4% (p<0.01) and 28.0% (p<0.05), respectively. Correction for USG reduces inter-individual and intra-individual variability in urine concentrations of salmeterol and α-hydroxysalmeterol.

Despite the growing evidence of role personality plays on sport and exercise related behavior, little is known about the influence of personality traits on football players in the U.S. The purpose of this study was to explore the effects of the big five personality traits on football achievements. Extraversion (E), Agreeableness (A), Conscientiousness (C), Neuroticism (N), and Openness (O) traits obtained from 619,397 U.S. respondents in a previous study were used as predictors to state-level football scores in this study. Across 50 states in the U.S., football ranks were positively correlated with state scores on the Big Five personality factors of conscientiousness and agreeableness. However, when applying multiple regression analyses to the prediction model for football ranks based on five independent variables of the Big Five personality factors, only conscientiousness and neuroticism would significantly predict football ranks. Agreeableness correlates with football ranks but does not contribute to the prediction model since agreeableness is collinear with conscientiousness, extraversion, and openness. Neuroticism insignificantly correlates with football ranks but contributes to the prediction because the suppressor effect of conscientiousness by neuroticism has improved its predictor of football ranks. The findings implied that in order to increase high ranks in football practice, selection for athletics would focus on persons with high conscientiousness and neuroticism.

Urine represents a valuable biofluid for noninvasive measurement of Human Growth Hormone (HGH) secretion. Unfortunately, currently available commercial HGH immunoassays do not achieve the sensitivity needed for urinary HGH measurement in the low picogram per milliliter range, the expected normal concentration range of HGH in urine.
A nanotechnology based sample preprocessing step was used to extract and concentrate HGH in urine so that urinary HGH could be measured with a clinical grade standard immunoassay designed for serum (Immulite 1000 ,Siemens). We applied the nanoparticle enhanced immunoassay to evaluate the baseline value of urinary HGH in a population of healthy young adults (age 18-30, N=33, median 21, M: F=39%:61%, with no reported medical therapies).
Nanoparticle sample preprocessing effectively improved the lower limit of detection of the Immulite HGH assay by more than 50 fold, shifting the linear range of the assay to encompass the expected value of urinary HGH. The full process between run and within run CV% was 7.9 and 9.0%, respectively. On 33 healthy volunteers, the 95% reference values for hGH in spot urine normalized to specific gravity were 0.64 - 16.85 pg/mL (0.05 -5.82 ng/g creatinine).
Nanoparticle preprocessing constitutes a reliable means of measuring urinary HGH with a clinical grade
immunoassay, now establishing a normal baseline value for HGH in urine. Nanoparticles can be used to study the kinetics of HGH excretion in urine, and the factors that influence urinary HGH secretion and HGH isoform proportions.