Metabolic changes in concussed American football players during the acute and chronic post-injury phases

<p>Abstract</p> <p>Background</p> <p>Despite negative neuroimaging findings many athletes display neurophysiological alterations and post-concussion symptoms that may be attributable to neurometabolic alterations.</p> <p>Methods</p> <p>The present study investigated the effects of sports concussion on brain metabolism using ¹H-MR Spectroscopy by comparing a group of 10 non-concussed athletes with a group of 10 concussed athletes of the same age (mean: 22.5 years) and education (mean: 16 years) within both the acute and chronic post-injury phases. All athletes were scanned 1-6 days post-concussion and again 6-months later in a 3T Siemens MRI.</p> <p>Results</p> <p>Concussed athletes demonstrated neurometabolic impairment in prefrontal and motor (M1) cortices in the acute phase where NAA:Cr levels remained depressed relative to controls. There was some recovery observed in the chronic phase where Glu:Cr levels returned to those of control athletes; however, there was a pathological increase of m-I:Cr levels in M1 that was only present in the chronic phase.</p> <p>Conclusions</p> <p>These results confirm cortical neurometabolic changes in the acute post-concussion phase as well as recovery and continued metabolic abnormalities in the chronic phase. The results indicate that complex pathophysiological processes differ depending on the post-injury phase and the neurometabolite in question.</p

Traitements inhibiteurs de la résorption osseuse en situation métastatique :bilan actuel et perspectives

The current main use of inhibitors of bone resorption, bisphosphonates and denosumab, is the prevention of the complications of bone metastases. Monthly infusions of zoledronic acid, the most potent bisphosphonate, decrease the complication rate of tumor-induced osteolysis by about 40%. Recent controlled double-blind phase III trials have demonstrated the superiority of denosumab against zoledronic acid to decrease skeletal morbidity in patients with bone metastases from breast or prostate cancer, and its noninferiority in a third trial including patients with other solid tumors or myeloma. The overall toxicity was similar between both compounds. It is recommended to start an inhibitor of bone resorption as soon as bone metastases are diagnosed, at least in patients with breast cancer. However, the optimal duration of therapy is unknown and we lack validated criteria to better individualize therapy and to define the place of intermittent treatments or of larger intervals between infusions. Lastly, recent studies indicate that zoledronic acid, but also clodronate, are able to reduce the risk of bone metastases and to prolong survival, at least in postmenopausal patients with breast cancer after surgery. This use of inhibitors of bone resorption in the adjuvant setting is not admitted yet although clinical practice is likely to change in the near future.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

If and when: intrinsic differences and environmental stressors influence migration in brown trout (Salmo trutta)

Partial migration is a common phenomenon, yet the causes of individual differences in migratory propensity are not well understood. We examined factors that potentially influence timing of migration and migratory propensity in a wild population of juvenile brown trout (Salmo trutta) by combining experimental manipulations with passive integrated transponder telemetry. Individuals were subjected to one of six manipulations: three designed to mimic natural stressors (temperature increase, food deprivation, and chase by a simulated predator), an injection of exogenous cortisol designed to mimic an extreme physiological challenge, a sham injection, and a control group. By measuring length and mass of 923 individuals prior to manipulation and by monitoring tagged individuals as they left the stream months later, we assessed whether pre-existing differences influenced migratory tendency and timing of migration, and whether our manipulations affected growth, condition, and timing of migration. We found that pre-existing differences predicted migration, with smaller individuals and individuals in poor condition having a higher propensity to migrate. Exogenous cortisol manipulation had the largest negative effect on growth and condition, and resulted in an earlier migration date. Additionally, low-growth individuals within the temperature and food deprivation treatments migrated earlier. By demonstrating that both pre-existing differences in organism state and additional stressors can affect whether and when individuals migrate, we highlight the importance of understanding individual differences in partial migration. These effects may carry over to influence migration success and affect the evolutionary dynamics of sub-populations experiencing different levels of stress, which is particularly relevant in a changing world