Beat-to-beat agreement of noninvasive tonometric and intra-radial arterial blood pressure during microgravity and hypergravity generated by parabolic flights.

Background: Accurate measurement of beat-to-beat arterial blood pressure is essential for understanding the cardiovascular adaptation to weightlessness; however, the intra-arterial standard of beat-to-beat blood pressure measurement has never been used during space flight because of its invasive nature.

Objectives: The aim of the present study was to compare noninvasive radial artery tonometry blood pressure measurement with intra-radial pressure measurement during microgravity and hypergravity generated by parabolic flights.

Methods: Two study participants, equipped with an intra-radial pressure line on the left arm and a Colin CBM-7000 (Colin Corp.

Long-term evaluation of sensorimotor and mnesic behaviour following striatal NMDA-induced unilateral excitotoxic lesion in the mouse.

Excitotoxic lesion of the striatum provides a useful model for evaluating the excitotoxic processes involved in neurological disorders, in particular stroke diseases. The behavioural outcome after such injury is however poorly described. We have therefore investigated the potential behavioural deficits induced by a NMDA-induced excitotoxic unilateral lesion of the lateral part of the striatum, by comparison with a PBS striatal injection (sham procedure), and non-operated mice behaviour.

Long-term functional outcome following transient middle cerebral artery occlusion in the rat: correlation between brain damage and behavioral impairment.

The assessment of both histological and functional long-term outcomes after cerebral ischemia is increasingly recommended for preclinical studies. Whereas correlations between behavioral impairments and primary ischemic lesion are documented, little is known about their relationships with remote nonischemic regions that undergo secondary degeneration, such as the thalamus. Anesthetized rats were subjected to mild (30 min) or severe (60 min) occlusion of the middle cerebral artery.

Sensorimotor and cognitive deficits after transient middle cerebral artery occlusion in the mouse.

Whereas behavioral impairments after stroke are increasingly studied in the rat, little is known about the long-term functional consequences of focal ischemia in the mouse. To address this issue, Swiss mice underwent transient (60 min) intraluminal occlusion of the middle cerebral artery (MCAo) or sham surgery. Sensorimotor (chimney, accelerating rotarod, pole, corner, adhesive removal and staircase tests) and cognitive (passive avoidance and Morris water maze) performances were regularly assessed during 1 month, after which the final histological lesion was measured.

Delayed administration of deferoxamine reduces brain damage and promotes functional recovery after transient focal cerebral ischemia in the rat.

The mechanisms underlying functional recovery after stroke are poorly understood. Brain-adaptive responses to the hypoxic stress elicited by ischemia could contribute to these mechanisms. Indeed, hypoxia-inducible factor-1 (HIF-1), one of the main transcriptional factors regulated by oxygen level, increases the expression of several beneficial genes such as erythropoietin, glucose transporter-1 and vascular endothelial growth factor.

Working memory and dopamine: clinical and experimental clues.

Working memory has been successively considered as a mnesic or executive process. The cognitive processes involved in working memory and the executive functions are closely linked. Most authors currently agree that executive functions include planning, attentional maintenance, mental flexibility and attentional inhibition.