Tissue hemoglobin monitoring is unable to follow variations of arterial hemoglobin during transitions from pulsatile to constant flow in cardiac surgery.

Objective: To test whether the variations of tissue hemoglobin concentration (∆THb) measured by the FORE-SIGHT(TM) cerebral oximeter can accurately detect changes in arterial hemoglobin concentration (∆AHb) before, during, and after cardiopulmonary bypass.

Design: A prospective clinical study.

Setting: Cardiac surgery operating room.

Temporal profile of amyloid-beta (Abeta) oligomerization in an in vivo model of Alzheimer disease. A link between Abeta and tau pathology.

Accumulation of amyloid-beta (Abeta) is one of the earliest molecular events in Alzheimer disease (AD), whereas tau pathology is thought to be a later downstream event. It is now well established that Abeta exists as monomers, oligomers, and fibrils. To study the temporal profile of Abeta oligomer formation in vivo and to determine their interaction with tau pathology, we used the 3xTg-AD mice, which develop a progressive accumulation of plaques and tangles and cognitive impairments.

Chronic nicotine administration exacerbates tau pathology in a transgenic model of Alzheimer's disease.

The association between nicotinic acetylcholine receptor (nAChR) dysfunction and cognitive decline in Alzheimer's disease (AD) has been widely exploited for its therapeutic potential. The effects of chronic nicotine exposure on Abeta accumulation have been studied in both humans and animal models, but its therapeutic efficacy for AD neuropathology is still unresolved. To date, no in vivo studies have addressed the consequences of activating nAChRs on tau pathology.