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Cécile Denis

Publications and source records attributed to Cécile Denis.

4 recordsLinked to original sources
PubMed2006

[Benzodiazepine withdrawal in subjects on opiate substitution treatment].

INTRODUCTION: Benzodiazepines are the most widely used psychotropic agents in the world. Abuse and dependence are reported in the general population and among drug misusers, including those dependent on heroine. Benzodiazepine use by heroine users increases their risk of overdose, not only from heroin but also substitution drugs such as methadone and more recently buprenorphine. Hence, detoxification from benzodiazepines is desirable. OBJECTIVE: The objective of this paper was to review the literature and determine the best benzodiazepine detoxification procedure for opiate-dependent individuals receiving substitution treatment. METHODS: Relevant studies were sought through systematic searches of Medline and Toxibase (a database focusing on substance abuse). RESULTS: There were fewer controlled studies than expected about benzodiazepine detoxification, and all of them excluded subjects who misused opiates or were in opiate substitution treatment. The best evidence supports a procedure where the patient is switched to a long-lasting benzodiazepine and the dose then tapered by 25% of the initial dose each week. Diazepam is the drug most often used in the framework. In opiate users, diazepam may raise special problems of misuse, as suggested by clinical and epidemiologic studies. Nonetheless, diazepam is the only benzodiazepine found to be effective for this withdrawal in controlled studies and some studies indicate that unprescribed diazepam use in heroin users is sometimes motivated by the desire to alleviate withdrawal symptoms and discomfort. CONCLUSION: Although diazepam appears to have potential for abuse, the available data does not rule out its therapeutic interest for benzodiazepine withdrawal in patients on opiate substitution treatment in an adequate treatment setting. Specific studies of this population are needed.

Anticonvulsants↗
PubMed2005

Constitutive hyperdopaminergia is functionally associated with reduced behavioral lateralization.

According to the dopamine (DA) hypothesis of schizophrenia and the strong evidence for decreased cerebral lateralization in schizophrenic patients, we postulated that hyperactivity of the dopaminergic system could be associated with a reduced behavioral lateralization in mice. Mice lacking the dopamine transporter (DAT) gene were used as a genetic model of persistent hyperdopaminergia. The DAT null mutation was transferred on C57BL/6JOrl (B6) and DBA/2JOrl (D2) inbred backgrounds for more than 10 generations of backcrossing to derive three DAT strains, B6, D2, and B6xD2(F1). Adult mutant mice of the three DAT strains and their littermates were tested for paw preference using Collins' protocol. Our results demonstrated that, whatever the genetic background, persistent hyperdopaminergia directly impairs the degree of lateralization without affecting the direction. Our results support the degree of lateralization as a good candidate phenotype to further improve genetic analysis of cerebral lateralization in normal and pathological conditions.

Animals↗
PubMed2004

Phenotypic expression of the targeted null-mutation in the dopamine transporter gene varies as a function of the genetic background.

The dopamine transporter (DAT) plays a critical role in calibrating the duration and intensity of dopamine (DA) neurotransmission. Mice in which the DAT gene has been genetically deleted exhibit constitutively high levels of extrasynaptic DA and spontaneous hyperactivity. Numerous studies have characterized the adaptive molecular, physiological, and behavioural consequences of abnormal DA neurotransmission in these mice. In order to determine the genetic background contribution to these phenotypes, the DAT mutation was transferred on C57BL/6JOrl (B6) or DBA/2JOrl (D2) inbred backgrounds for more than ten generations of back-crossing to derive three B6-, D2-, and B6xD2(F(1))-DAT strains. We observed that the genetic background dramatically affects phenotypes previously reported on DAT knockout (KO) mice. Depending on the genetic background, it was possible to restore survival, growth rate and ability to lactate. Interactions with the genetic background were found to modulate both quantitative and qualitative patterns of novelty-driven spontaneous hyperactivity. The paradoxical calming effect of cocaine was observed for all DAT-KO mice. However, the genetic background influenced individual threshold responses to both locomotor and rewarding effects of cocaine. These findings reveal the extent of phenotypic variation associated with the DAT mutation. They also provide concrete arguments against the assumption that the normal function of a gene can be inferred directly from its mutant phenotype.

Analysis of Variance↗