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The purpose of this study was to investigate the neuromuscular and perceptual fatigue responses of elite rugby players during the inaugural Under-18 (U18) Six Nations Festival. One hundred and thirty-three male players from five national squads (73 forwards, 60 backs) were examined during the competition. Each national squad was involved in three matches separated by 96 h each. Over the competition, players completed a daily questionnaire to monitor perceived well-being (WB) and performed daily countermovement jumps (CMJ) to assess neuromuscular function (NMF). Reductions in WB were substantial 24 h after the first and second match in forwards (d=0.77±0.21, p<0.0001; d=0.84±0.22, p< 0.001) and backs (d=0.89±0.22, p <0.0001; d=0.58±0.23, p<0.0001) but reached complete recovery in time for the subsequent match. Reductions in CMJ height were substantial 24 h after the first and second match for forwards (d=0.31±0.15, p=0.001; d=0.25±0.17, p=0.0205) and backs (d=0.40±0.17, p=0.0001; d=0.28±0.17, p=0.0062) and recovered at 48 h after match-play. Average WB and CMJ height attained complete recovery within matchday cycles in the investigated international competition. The findings of this study can be useful for practitioners and governing bodies involved with fixture scheduling and training prescription during competitive periods. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs), which are regarded as promising candidates for cell replacement therapies, are able to regulate immune responses after traumatic brain injury (TBI). Secondary immune response following the mechanical injury is the essential factor leading to the necrosis and apoptosis of neural cells during and after the cerebral edema has subsided and there is lack of efficient agent that can mitigate such neuroinflammation in the clinical application. By means of three molecular pathways (prostaglandin E2 (PGE2), tumor-necrosis-factor-inducible gene 6 protein (TSG-6), and progesterone receptor (PR) and glucocorticoid receptors (GR)), MSCs induce the activation of macrophages/microglia and drive them polarize into the M2 phenotypes, which inhibits the release of pro-inflammatory cytokines and promotes tissue repair and nerve regeneration. The regulation of MSCs and the polarization of macrophages/microglia are dynamically changing based on the inflammatory environment. Under the stimulation of platelet lysate (PL), MSCs also promote the release of pro-inflammatory cytokines. Meanwhile, the statue of macrophages/microglia exerts significant effects on the survival, proliferation, differentiation and activation of MSCs by changing the niche of cells. They form positive feedback loops in maintaining the homeostasis after TBI to relieving the secondary injury and promoting tissue repair. MSC therapies have obtained great achievements in several central nervous system disease clinical trials, which will accelerate the application of MSCs in TBI treatment. [ABSTRACT FROM PUBLISHER]

Many college students underestimate or ignore the side-effects associated with nonmedical use of prescription stimulants (NMUPS) and are motivated by hopes of academic enhancement. The present study measured the effect a placebo stimulant and personal expectancies have on subjective physiological changes and cognitive enhancement. Undergraduate college students participated in a two-phase study. Phase 1 (n = 305) involved completing an online survey to gather distal study variables and individual stimulant expectancy data. Phase 2 (n = 166) required students to attend an in-person session where they completed physiological and neuropsychological measures (e.g., Physical Symptom Checklist, Digit Span, Passage Comprehension). Students were randomized to receive a placebo stimulant medication (experimental) or no medication (control). Following a 30-minute absorption period, participants completed another set of physiological and neuropsychological measures. Experimental participants reported significant increases in positive symptoms resulting from the placebo stimulant. Expectancies moderated the impact of the placebo stimulant on Passage Comprehension performance; no other neuropsychological task performance was impacted. Despite subjective reports of feeling the effects of stimulants, task performance was unaffected. Moreover, expectancies may play a small role in perceptions of the effects of stimulants. [ABSTRACT FROM PUBLISHER]

Adenosine is a naturally occurring purine nucleoside in every cell. Many critical treatments such as modulating irregular heartbeat (arrhythmias), regulation of central nervous system (CNS) activity and inhibiting seizural episodes can be carried out using adenosine. Despite the significant potential therapeutic impact of adenosine and its derivatives, the severe side effects caused by their systemic administration have significantly limited their clinical use. In addition, due to adenosine’s extremely short half-life in human blood (<10 s), there is an unmet need for sustained delivery systems to enhance efficacy and reduce side effects. In this article, various adenosine delivery techniques, including encapsulation into biodegradable polymers, cell-based delivery, implantable biomaterials and mechanical-based delivery systems, are critically reviewed and the existing challenges are highlighted. [ABSTRACT FROM PUBLISHER]