Biomedical subjects

Dominique J-F de Quervain

Publications and source records attributed to Dominique J-F de Quervain.

6 recordsLinked to original sources

PubMed2024

The effect of fampridine on working memory: a randomized controlled trial based on a genome-guided repurposing approach.

Working memory (WM), a key component of cognitive functions, is often impaired in psychiatric disorders such as schizophrenia. Through a genome-guided drug repurposing approach, we identified fampridine, a potassium channel blocker used to improve walking in multiple sclerosis, as a candidate for modulating WM. In a subsequent double-blind, randomized, placebo-controlled, crossover trial in 43 healthy young adults (ClinicalTrials.gov, NCT04652557), we assessed fampridine's impact on WM (3-back d-prime, primary outcome) after 3.5 days of repeated administration (10 mg twice daily). Independently of baseline cognitive performance, no significant main effect was observed (Wilcoxon P = 0.87, r = 0.026). However, lower baseline performance was associated with higher working memory performance after repeated intake of fampridine compared to placebo (rs = -0.37, P = 0.014, n = 43). Additionally, repeated intake of fampridine lowered resting motor threshold (F(1,37) = 5.31, P = 0.027, R2β = 0.01), the non-behavioral secondary outcome, indicating increased cortical excitability linked to cognitive function. Fampridine's capacity to enhance WM in low-performing individuals and to increase brain excitability points to its potential value for treating WM deficits.

Adult↗

PubMed2004

Stress doses of hydrocortisone, traumatic memories, and symptoms of posttraumatic stress disorder in patients after cardiac surgery: a randomized study.

BACKGROUND: Traumatic experiences associated with cardiac surgery (CS) can result in traumatic memories and posttraumatic stress disorder (PTSD). Because it is known that subjects who develop PTSD often show sustained reductions in circulating cortisol concentrations, we performed a prospective, randomized study to examine whether exogenously administered stress doses of hydrocortisone during the perioperative period of CS reduces the long-term incidence of chronic stress and PTSD symptoms. METHODS: Patients (n = 91) were prospectively randomized to receive either stress doses of hydrocortisone or standard treatment during the perioperative period of CS. Of 48 available patients at 6 months after CS, 26 had received stress doses of hydrocortisone and 22 standard treatment. Traumatic memories and PTSD symptoms were diagnosed with previously validated questionnaires. RESULTS: As compared with patients after standard therapy, patients from the hydrocortisone group had significantly lower chronic stress symptom scores (p <.05). There was no significant difference regarding the number or type of traumatic memories between the hydrocortisone and the standard treatment groups. CONCLUSIONS: Stress doses of hydrocortisone in patients undergoing CS are associated with a lower intensity of chronic stress and PTSD symptoms at 6 months after CS.

Aged↗

PubMed2004

A systemically administered beta-adrenoceptor antagonist blocks corticosterone-induced impairment of contextual memory retrieval in rats.

Several studies have reported that glucocorticoids impair memory retrieval. The present study examined in male Sprague-Dawley rats the effects of systemically administered corticosterone on retrieval of memory for inhibitory avoidance training. Corticosterone (3.0mg/kg, s.c.) injected 30min before retention testing, 48h after training, significantly impaired retention performance, as compared to vehicle treatment, of rats tested in the training context. In contrast, corticosterone administration did not impair retrieval when rats were tested for retention in a different context. Corticosterone did also not impair retention performance of rats given a mild-intensity footshock that resulted in only weak, non-contextual memory. These findings strongly suggest that corticosterone selectively impaired retrieval of contextual information associated with the training context. The centrally acting beta-adrenoceptor antagonist propranolol (2.0mg/kg), co-administered in a dose that did not affect retention performance alone, blocked the impairment in contextual memory retrieval induced by corticosterone. These findings provide evidence for the view that glucocorticoids interact with noradrenergic mechanisms in influencing memory retrieval.

Adrenal Cortex Hormones↗

PubMed2003

Glucocorticoid-related genetic susceptibility for Alzheimer's disease.

Because glucocorticoid excess increases neuronal vulnerability, genetic variations in the glucocorticoid system may be related to the risk for Alzheimer's disease (AD). We analyzed single-nucleotide polymorphisms in 10 glucocorticoid-related genes in a population of 814 AD patients and unrelated control subjects. Set-association analysis revealed that a rare haplotype in the 5' regulatory region of the gene encoding 11beta-hydroxysteroid dehydrogenase type 1 (HSD11B1) was associated with a 6-fold increased risk for sporadic AD. Results of a reporter-gene assay indicated that the rare risk-associated haplotype altered HSD11B1 transcription. HSD11B1 controls tissue levels of biologically active glucocorticoids and thereby influences neuronal vulnerability. Our results indicate that a functional variation in the glucocorticoid system increases the risk for AD, which may have important implications for the diagnosis and treatment of this disease.

11-beta-Hydroxysteroid Dehydrogenase Type 1↗

PubMed2003

A functional genetic variation of the 5-HT2a receptor affects human memory.

Human memory capacity is highly variable across individuals and is influenced by both genetic and environmental factors. A roughly 50% heritability estimate indicates that naturally occurring genetic variations have an important impact on this cognitive ability. Therefore, we investigated a functional variation of a memory-related serotonin receptor in 349 healthy young volunteers, and found 21% poorer memory performance in subjects with the rare variant.

Case-Control Studies↗

PubMed2003

Glucocorticoid-induced impairment of declarative memory retrieval is associated with reduced blood flow in the medial temporal lobe.

Previous work indicates that stress levels of circulating glucocorticoids can impair retrieval of declarative memory in human subjects. Several studies have reported that declarative memory retrieval relies on the medial temporal lobe. The present study used H(2)(15)O-positron emission tomography to investigate whether acutely elevated glucocorticoid levels affect regional cerebral blood flow in the medial temporal lobe, as well as in other brain regions, during declarative memory retrieval in healthy male human subjects. When measured over four different declarative memory retrieval tasks, a single, stress-level dose of cortisone (25 mg) administered orally 1 h before retention testing, induced a large decrease in regional cerebral blood flow in the right posterior medial temporal lobe, the left visual cortex and the cerebellum. The decrease in the right posterior medial temporal lobe was maximal in the parahippocampal gyrus, a region associated with successful verbal memory retrieval. Cortisone administration also significantly impaired cued recall of word pairs learned 24 h earlier, while drug effects on performance in the other tasks (verbal recognition, semantic generation and categorization) were not significant. The present results provide further evidence that acutely elevated glucocorticoid levels can impair declarative memory retrieval processes and suggest that such impairments may be related to a disturbance of medial temporal lobe function.

Adult↗