Is there diurnal variation in neuroprotective and thrombolytic therapy effect upon acute cerebral ischemia outcome?

Background: Preclinical studies have found marked diurnal/circadian variation in the effect of neuroprotective agents in acute ischemic stroke. However, the presence of diurnal variation in treatment outcomes after neuroprotective therapy has not been analyzed in human clinical trials and variation after thrombolytic therapy has been under-studied.

Methods: We analyzed patients with acute cerebral ischemia enrolled in the Field Administration of Stroke Therapy - Magnesium (FAST-MAG) randomized trial of magnesium sulfate started in the ambulance within two hours of stroke onset (last known well time).

Purposeful Sampling: Advantages and Pitfalls.

This editorial monograph explores the advances and pitfalls of the common forms of purposeful sampling. Purposeful sampling is a common research design in qualitative research.

Modular switches shift monarch butterfly migratory flight behavior at their Mexican overwintering sites.

Eastern North American migratory monarch butterflies exhibit migratory behavioral states in fall and spring characterized by sun-dependent oriented flight. However, it is unclear how monarchs transition between these behavioral states at their overwintering site. Using a modified Mouritsen-Frost flight simulator, we confirm individual directionality and compass-based orientation (leading to group orientation) in fall migrants, and also uncover sustained flight propensity and direction-based flight reinforcement as distinctly migratory behavioral traits.

Magnesium and Hematoma Expansion in Intracerebral Hemorrhage: A FAST-MAG Randomized Trial Analysis.

Background: Observational studies suggest that magnesium may have hemostatic effects. FAST-MAG (Field Administration of Stroke Therapy-Magnesium) was a pragmatic clinical trial of magnesium sulfate administered prehospital for acute clinical stroke syndromes and included patients with intracerebral hemorrhage. Exploratory secondary analysis by the treatment group found no reduction in hematoma expansion (HE) associated with magnesium treatment in intracerebral hemorrhage but did not consider serum magnesium levels achieved.