Emotional trait and memory associates of sleep timing and quality.

Poor ability to remember the extinction of conditioned fear, elevated trait anxiety, and delayed or disrupted nocturnal sleep are reported in anxiety disorders. The current study examines the interrelationship of these factors in healthy young-adult males. Skin-conductance response was conditioned to two differently colored lamps.

Extinction of conditioned fear is better learned and recalled in the morning than in the evening.

Sleep helps emotional memories consolidate and may promote generalization of fear extinction memory. We examined whether extinction learning and memory might differ in the morning and evening due, potentially, to circadian and/or sleep-homeostatic factors. Healthy men (N = 109) in 6 groups completed a 2-session protocol.

Modeling reconsolidation in kernel associative memory.

Memory reconsolidation is a central process enabling adaptive memory and the perception of a constantly changing reality. It causes memories to be strengthened, weakened or changed following their recall. A computational model of memory reconsolidation is presented.

Sleep promotes consolidation and generalization of extinction learning in simulated exposure therapy for spider fear.

Simulated exposure therapy for spider phobia served as a clinically naturalistic model to study effects of sleep on extinction. Spider-fearing, young adult women (N = 66), instrumented for skin conductance response (SCR), heart rate acceleration (HRA) and corrugator electromyography (EMG), viewed 14 identical 1-min videos of a behaving spider before a 12-hr delay containing a normal night's Sleep (N = 20) or continuous daytime Wake (N = 23), or a 2-hr delay of continuous wake in the Morning (N = 11) or Evening (N = 12). Following the delay, all groups viewed this same video 6 times followed by six 1-min videos of a novel spider.

Menometrorrhagia in magnetic resonance imaging operators with copper intrauterine contraceptive devices (IUDS): a case report.

The paper describes the cases of 3 female health operators with implanted copper IUDs, developing menometrorrhagia some months after an increase of the working time in a Magnetic Resonance Imaging (MRI) Unit (1.5 T), that progressively disappeared when the previous organization, involving discontinuous work shifts at MRI, was re-established. No known factors possibly related to menometrorrhagia were evidenced in the 3 operators, supporting the hypothesis of a role of the exposure to the electromagnetic fields (EMF) induced by the MRI system in symptoms induction.

Interference of heparin in plasma levocarnitine determination with radioenzyme assay.

This paper describes the interference of heparin (CAS 9005-49-6) in whole plasma used for free and total levocarnitine (L-carnitine, CAS 541-15-1) analysis. Alkaline hydrolysis required for total L-carnitine measurement does not overcome the problem. The same interference is also present in long-chain acyl-L-carnitine assay, because heparin precipitates together with proteins and long-chain esters of L-carnitine in the acid insoluble fraction of perchloric acid treated plasma sample.

Measurement of glomerular filtration rate by impulse synthesis: clinical validation and optimization.

Impulse synthesis is a technique which relies upon the logic of continuous infusion but extracts the clearance value from single-injection data by shifting and adding them until an asymptotic value is attained. This study has been aimed at validating and optimizing clinically the measurement of glomerular filtration rate by impulse synthesis. A single intravenous injection of 51Cr-EDTA has been made in 32 patients and plasma activity monitored over the next 6 h.