Variability of acute physiological responses and performance profiles of youth soccer players in small-sided games

The aim of this study was to examine the variability in physiological and perceptual responses and time-motion profiles of various small-sided soccer game (SSG) formats (2 versus 2, 4 versus 4 and 6 versus 6 players) and regimes (interval and continuous). Typical error (TE) was calculated for mean heart rate as a percentage of maximum heart rate (%HR(max)), global ratings of perceived exertion (RPE), blood lactate [La(-)] and various time-motion characteristics for 16 male soccer players (mean 16.2 years, range 15.6-17.9). The TE for HR responses were <5% for all SSGs. RPE also demonstrated small variability across all SSGs, with TE ranging between 1 and 2 units. In contrast, the TE% for [La(-)] was higher, ranging from 16% (2 versus 2-interval) to 34% (4 versus 4-interval). The TE% for total distance (TD) and distance covered at 0-6.9km/h was <5% for all SSGs, with 2 versus 2 interval and continuous games recording the lowest TE (2.2% and 2.9%, respectively). An increase in game format size does not appear to influence the variability of the acute physiological responses to SSGs, although continuous formats display less variability than interval formats. The TD, distance covered and percentage of total time moving at 0-6.9km/h demonstrated small variability across all formats and regimes. However, higher movement speeds zones (>8km/h) reflected increased variability, irrespective of game format or regime. Collectively, these results suggest that SSG training can provide a reliable aerobic training stimulus.     

Bcl-2-related protein A1 is an endogenous and cytokine-stimulated mediator of cytoprotection in hyperoxic acute lung injury

Hyperoxic acute lung injury (HALI) is characterized by a cell death response with features of apoptosis and necrosis that is inhibited by IL-11 and other interventions. We hypothesized that Bfl-1/A1, an antiapoptotic Bcl-2 protein, is a critical regulator of HALI and a mediator of IL-11-induced cytoprotection. To test this, we characterized the expression of A1 and the oxygen susceptibility of WT and IL-11 Tg(+) mice with normal and null A1 loci. In WT mice, 100% O(2) caused TUNEL(+) cell death, induction and activation of intrinsic and mitochondrial-death pathways, and alveolar protein leak. Bcl-2 and Bcl-xl were also induced as an apparent protective response. A1 was induced in hyperoxia, and in A1-null mice, the toxic effects of hyperoxia were exaggerated, Bcl-2 and Bcl-xl were not induced, and premature death was seen. In contrast, IL-11 stimulated A1, diminished the toxic effects of hyperoxia, stimulated Bcl-2 and Bcl-xl, and enhanced murine survival in 100% O(2). In A1-null mice, IL-11-induced protection, survival advantage, and Bcl-2 and Bcl-xl induction were significantly decreased. VEGF also conferred protection via an A1-dependent mechanism. In vitro hyperoxia also stimulated A1, and A1 overexpression inhibited oxidant-induced epithelial cell apoptosis and necrosis. A1 is an important regulator of oxidant-induced lung injury, apoptosis, necrosis, and Bcl-2 and Bcl-xl gene expression and a critical mediator of IL-11- and VEGF-induced cytoprotection.     

Street drug abuse leading to critical illness

Critical care physicians are frequently confronted with intoxicated patients who have used street drugs. In the last decade there has been an upward trend in the use of these substances, particularly amongst adolescents and young adults in large urban areas. In excess quantities all street drugs can lead to critical illness. Early and appropriate medical attention by emergency medicine physicians and intensivists can improve outcomes. In this review article we intend to familiarize critical care physicians with the most common street drugs such as amphetamines, ecstasy, cocaine, gamma hydroxybutyrate, opioids, and phencyclidine.