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P Nuss

Publications and source records attributed to P Nuss.

8 recordsLinked to original sources

A positron emission tomography (PET) study of cerebral dopamine D2 and serotonine 5-HT2A receptor occupancy in patients treated with cyamemazine (Tercian).

RATIONALE: Cyamemazine (Tercian) is an antipsychotic drug with anxiolytic properties. Recently, an in vitro study showed that cyamemazine possesses high affinity for serotonin 5-HT(2A) receptors, which was fourfold higher than its affinity for dopamine D(2) receptors (Hameg et al. 2003). OBJECTIVES: The aim of this study is to confirm these previous data in vivo in patients treated with clinically relevant doses of Tercian. METHODS: Eight patients received 37.5, 75, 150 or 300 mg/day of Tercian depending on their symptomatology. Dopamine D(2) and serotonin 5-HT(2A) receptor occupancies (RO) were assessed at steady-state plasma levels of cyamemazine with positron emission tomography (PET), using [(11)C]raclopride and [(11)C]N-methyl-spiperone, respectively. The effective plasma level of the drug leading to 50% of receptor occupancy was estimated by fitting RO with plasma levels of cyamemazine at the time of the PET scan. RESULTS: Cyamemazine induced near saturation of 5-HT(2A) receptors (RO=62.1-98.2%) in the frontal cortex even at low plasma levels of the drug. On the contrary, occupancy of striatal D(2) receptors increased with plasma levels, and no saturation was obtained even at high plasma levels (RO=25.2-74.9%). The effective plasma level of cyamemazine leading to 50% of D(2) receptor occupancy was fourfold higher than that for 5-HT(2A) receptors. Accordingly, individual 5-HT(2A)/D(2) RO ratios ranged from 1.26 to 2.68. No patients presented relevant increased prolactin levels, and only mild extrapyramidal side effects were noticed on Simpson and Angus Scale. CONCLUSION: This in vivo binding study conducted in patients confirms previous in vitro findings indicating that cyamemazine has a higher affinity for serotonin 5-HT(2A) receptors compared to dopamine D(2) receptors. In the dose range 37.5-300 mg, levels of dopamine D(2) occupancy remained below the level for motor side effects observed with typical antipsychotics and is likely to explain the low propensity of the drug to induce extrapyramidal side effects.

Adult↗

Reduction of extracellular dopamine and metabolite concentrations in rat striatum by low doses of acute cyamemazine.

The low incidence of extrapyramidal effects with atypical neuroleptics has been ascribed to their 5-HT(2A)- and 5-HT(2C)-serotonin receptor antagonistic properties. On the other hand, the acute increase in striatal dopamine release by submaximal dopamine D(2) autoreceptor blockade can be respectively reduced and increased by 5-HT(2A)- and 5-HT(2C)-antagonists. Cyamemazine is a neuroleptic D(2)- and 5-HT(2A)-receptor antagonist, with small antagonistic activity at 5-HT(2C) receptors and low incidence of extrapyramidal side effects. Therefore, submaximal cyamemazine was tested in rats for its acute action on the extracellular concentrations of dopamine and dopamine metabolites (DOPAC: 3,4,dihydroxyphenylacetic acid and HVA: 4-hydroxy-3-methoxy-phenyl-acetic acid) in the corpus striatum. The serotonin metabolite 5-HIAA (5-hydroxy-indole-acetic acid) was measured in parallel. Rats prepared for microdialysis (striatum) were intraperitoneally given cyamemazine 1 mg/kg, 5 mg/kg or vehicle ( n=4 in each group). Dopamine, DOPAC, HVA and 5-HIAA concentrations in perfusates under basal conditions and after stimulation by high K(+) were measured by HPLC coupled to electrochemical detection. Cyamemazine 1 mg/kg significantly reduced extracellular concentrations of basal dopamine (-77%), DOPAC (-54%), HVA (-54%) and 5-HIAA (-65%). No such effects were seen with the dose of cyamemazine 5 mg/kg or for K(+)-evoked dopamine release. In conclusion, submaximal cyamemazine can acutely reduce basal dopamine release and metabolism in the rat striatum. Such unusual action can be explained by the original pharmacological profile of cyamemazine (potent D(2)- and 5-HT(2A)-antagonist, with small antagonistic activity at 5-HT(2C) receptors). Further experiments are required to explain the low incidence of extrapyramidal side actions with cyamemazine.

3,4-Dihydroxyphenylacetic Acid↗

What is the schizophrenic patients' level of information about their disease and their treatment?

Improved compliance with antipsychotic medication is a major issue in schizophrenic management. For this purpose educational programs have been used, but up to now, little or no information has been gathered or published in France concerning schizophrenic patients' opinion on information they have about their disease and their treatment. Thus we conducted a survey in concert with 78 psychiatrists from the French psychiatric health service. From this cross sectional survey we assessed 336 outpatients (male: 72%; mean age: 36 +/- 10.4 years) with schizophrenia according to the DSM IV (paranoid sub type: 57%, disorganized: 12%, catatonic: 1%, undifferentiated: 12%, residual: 18%). The mean duration of the illness was 11.6 years (sd: 8.5) and the mean duration of the follow up with the same psychiatrist was 5.4 years (sd: 5.1). Patients completed a questionnaire which assessed their level of information on mental illness and treatment. The diagnosis of schizophrenia has been told to their patients by 39% of the psychiatrists, and treatment has been explained to the patients by 96% of the practitioners. Results indicate less than half of the patients (45%) felt ill, only 46% thought they knew their illness well or very well (nevertheless only 31% of them named spontaneously the diagnosis of schizophrenia or psychosis), and 61% considered that they had been given sufficient information. Most of the patients (79%) were persuaded that their treatment was useful, and 75% of patients were completely satisfied with their treatment. Surprisingly 92% reported taking their medication regularly. Most patients think that a high level of information about their illness (74%) and treatment (79%) help them to cope better with their schizophrenia. Analysis performed according to patients characteristics indicated that paranoid patients felt more ill (p = 0.035) than others, thought to know less about their illness (p = 0.0065), and were less satisfied with their treatment (p = 0.04) and their level of information (p = 0.03). Patients with a duration of their illness longer than 10 years were more convinced of the utility of their treatment (p = 0.02) and had debated more on the choice of their treatment with their psychiatrist (p = 0.047). Patients older than 35 years were more satisfied with their information (p = 0.002). More patients with atypical antipsychotics accepted to take their treatment on a regular basis (p = 0.035) compared to patients under classical neuroleptics. This survey underlines that mental health consumers' opinions can be obtained even in the field of schizophrenia, and argues in favour of further such investigations. It also highlights the need for educational programs on schizophrenia and antipsychotic medications.

Adult↗

[When and how to stop anxiolytic drugs].

The anxiolytics withdrawal constitutes a frequently desirable therapeutic situation in which it is necessary to integrate clinical data related to the disorder for which they were prescribed as well as the pharmacological and psychological aspects. Personality features and emotional environment of the patient are to be considered. This withdrawal follows a first step in which the anxiolytics were initially prescribed. This situation happens in medicine in multiple clinical situations. However, because of the phenomena of tolerance and dependence but also according to the efficacy of the anti-depressants in most anxiety disorders, benzodiazepines are described in France as over-prescribed molecules. General rules of prescription are a prelude to a good withdrawal process. This last must always be prevented especially when the dosage is high occurring after a long duration treatment. A good guideline for the initial prescription is a good ticket to anticipate the withdrawal time.

Anti-Anxiety Agents↗

[Dysthymic disorders].

Long lasting, low intensity depressive episodes have been diversely integrated according to the classifications types or the psychodynamic points of view. The concept of anxious persistent lasting depression, neurotic depressive states, neurotic depression ... have been unified into the dysthymic disorder category of the DSM classification. This concept unification have been a topic of dispute considering that dysthymic disorder was a restrictive, heterogeneous an extensively comorbid diagnosis. Nevertheless the definition of this category offers the opportunity to place the notions of temperament, personality, adjustment disorder. Including dysthymic disorders as a category inside of the mood disorders classification suggests the interest of using an antidepressive medication in presence of chronic depressive states not included in the major depressive disorder category.

Adjustment Disorders↗

[What information do patients with schizophrenia have about their illness and treatment?].

Improved compliance with antipsychotic medication is a major issue in schizophrenic management. For this purpose educational programs have been used, but up to now, little or no information has been gathered or published in France concerning schizophrenic patients' opinion on information they have about their disease and their treatment. Thus we conducted a survey in concert with 78 psychiatrists from the French psychiatric health service. From this cross sectional survey we assessed 336 outpatients (male: 72%; mean age: 36 +/- 10.4 years) with schizophrenia according to the DSM IV (paranoid sub type: 57%, disorganized: 12%, catatonic: 1%, undifferentiated: 12%, residual: 18%). The mean duration of the illness was 11.6 years (sd: 8.5) and the mean duration of the follow up with the same psychiatrist was 5.4 years (sd: 5.1). Patients completed a questionnaire which assessed their level of information on mental illness and treatment. The diagnosis of schizophrenia has been told to their patients by 39% of the psychiatrists, and treatment has been explained to the patients by 96% of the practitioners. Results indicate less than half of the patients (45%) felt ill, only 46% thought they knew their illness well or very well (nevertheless only 31% of them named spontaneously the diagnosis of schizophrenia or psychosis), and 61% considered that they had been given sufficient information. Most of the patients (79%) were persuaded that their treatment was useful, and 75% of patient were completely satisfied with their treatment. Surprisingly 92% reported taking their medication regularly. Most patients think that a high level of information about their illness (74%) and treatment (79%) help them to cope better with their schizophrenia. Analysis performed according to patients characteristics indicated that paranoid patients felt more ill (p = 0.035) than others, thought to know less about their illness (p = 0.0065), and were less satisfied with their treatment (p = 0.04) and their level of information (p = 0.03). Patients with a duration of their illness longer than 10 years were more convinced of the utility of their treatment (p = 0.02) and had debated more on the choice of their treatment with their psychiatrist (p = 0.047). Patients older than 35 years were more satisfied with their information (p = 0.002). More patients with atypical antipsychotics accepted to take their treatment on a regular basis (p = 0.035) compared to patients under classical neuroleptics. This survey underlines that mental health consumers' opinions can be obtained even in the field of schizophrenia, and argues in favour of further such investigations. It also highlights the need for educational programs on schizophrenia and antipsychotic medications.

Adaptation, Psychological↗

[Is the anxious patient dependent?].

To answer the question: is the anxious a dependant person, it is necessary to define to what extend behaviour depends on pathology. The difficulty in answering this question relies on the fact that these two phenomenons interact with each other. The comorbidity analysis allows a descriptive point of view. It shows a higher incidence of these troubles when occurring together, compared to a general population. Nevertheless, the comorbidity approach does not give any information on the nature of the links between anxiety and dependence. The causality models depend on the theory they use. Furthermore, unity between anxiety and dependence disorders does not exist; it is then certainly a mistake to consider their link in a unique way. Three main hypothesis are usually used. The neurobiology point of view supposes a link between brain structures, neurofunctioning, anxiety and dependence disorders. Some authors suggest a general addictive propensity of brain functioning, especially in cases of anxiety disorders. Lastly, the psychopathological analysis can be useful in the understanding of dependence behaviour in case of anxiety.

Alcoholism↗