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S Dollfus

Publications and source records attributed to S Dollfus.

At least 37 records · Page 2Linked to original sources
PubMed1996

Association study between schizophrenia and monoamine oxidase A and B DNA polymorphisms.

Monoamine oxidases (MAO) A and B, which are encoded by two distinct genes located on the human X chromosome, are both involved in the oxidative metabolism of dopamine. Decreased levels of platelet MAO-B activity has been reported in patients with schizophrenia and genetic variation in MAO activity had been proposed as a significant factor in the etiology of this disease. We carried out an association study using two intragenic polymorphisms within the MAO-A and MAO-B genes in 110 schizophrenic patients and 87 control subjects. For each polymorphic marker, no significant difference in allelic frequencies was observed between patients and controls. Nevertheless, a trend toward an association between allele 1 of the MAO-B gene and paranoid schizophrenia was found. Our results do not support the hypothesis that inherited variants of MAO genes might play a major role in a genetic predisposition to schizophrenia. Since several previous reports found a low MAO-B platelet activity in patients with paranoid schizophrenia, the identification of polymorphisms related to enzyme activity would be useful.

Adolescent↗
PubMed1996

Identifying subtypes of schizophrenia by cluster analyses.

The existence of two subtypes of schizophrenia (positive and negative) is well established. The evidence in favor of other subtypes, particularly a disorganized subtype, is still the subject of some debate. The aim of the study reported in this article is to investigate the possibility of further subtypes of schizophrenia by applying a particular method of cluster analysis to a particular set of data. Ward's method of cluster analysis was applied to the Positive and Negative syndrome Scale (PANSS) scores of 138 patients, defined as having schizophrenia by one of four diagnostic criteria. The validity of the cluster solution was assessed both by examining differences between clusters on a number of clinical characteristics recorded for each patient and by comparing the results obtained from the PANSS with those derived from a cluster analysis using two other instruments (the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms). Results from the cluster analysis suggest the existence of at least four subtypes of schizophrenia: positive, negative, mixed, and disorganized. A fifth subtype includes patients with few symptoms, suggesting the simple schizophrenia named by Bleuler. Evidence for the validity of these subtypes was provided by the differences observed between the clusters on a number of clinical characteristics and by the similarity of the cluster solution obtained from the different instruments. In conclusion, the negative-positive dichotomy in schizophrenia is an oversimplification, and the existence of a more complex structure needs to be taken into account in future research.

Adult↗
PubMed1996

[Stability of positive/negative symptoms in schizophrenia].

The debate concerning the stable or instable aspect of schizophrenic symptomatology has lead the authors to study this phenomenon by taking into account, at the time of inclusion of a schizophrenic patient, such parameters as: the phase of the illness (acute, post-acute or stable) or the course (chronicity) as well as the relationship between the negative symptomatology variation and other symptomatic dimension variation (depression, akinesia, etc.), in follow-up studies. The results of these studies are clearly in favour of taking into consideration all or part of these parameters, to evaluate at best the stability of positive and negative schizophrenic symptoms.

Delusions↗
PubMed1996

A comparison of an atypical and typical antipsychotic, zotepine versus haloperidol in patients with acute exacerbation of schizophrenia: a parallel-group double-blind trial.

The atypical antipsychotic zotepine was compared to haloperidol in 126 patients suffering from acute exacerbation of schizophrenia (DSM-III-R) in a randomized, double-blind study. After 8-weeks, 150 to 300 mg zotepine improved scores on the Brief Psychiatric Rating Scale (BPRS) more than 10 to 20 mg haloperidol (-17.03 versus -13.45; 95%CI for zotepine-haloperidol -9.34/2.04). BPRS subscores and Clinical Global impressions (CGI) Severity and improvement subscales showed comparable gains, but scores on the Scale for the Assessment of Negative Symptoms (SANS) improved significantly more with zotepine (-23.82) than haloperidol (-15.15; P < .05; 95%CI for zotepine haloperidol -18.03/-0.18). Adverse events were reported by 71 percent of zotepine and 78 percent of haloperidol patients. Extrapyramidal side effect (EPMS) scores decreased with zotepine (-0.34) but increased with haloperidol (+2.32; P < .05). Seven haloperidol patients reported akathisia but no zotepine patients did (p < .05). Uric acid reductions (which appear to have no clinical consequence) and transient raised liver enzymes were recorded with zotepine. Weight increased on zotepine (2.32 kg; P < .001) and a small increase in pulse rate occurred (P < .05). Both drugs were effective in reducing positive symptoms of schizophrenia; zotepine was significantly more effective against negative symptoms and reduced EPMS.

Adult↗
PubMed1995

No evidence for linkage or association between the dopamine transporter gene and schizophrenia in a French population.

Pharmacological and clinical findings suggest that the dopamine transporter (DAT) gene may be involved in the genetic predisposition to schizophrenia. Linkage of a Taq I VNTR polymorphism in the DAT gene to schizophrenia was studied in multiplex schizophrenic families from Rouen, France (n = 10) and the Island of La Réunion (n = 21). Neither the lod score method nor nonparametric methods (the affected pedigree member method of Weeks and Lange [1988] and the sibling method of Green and Woodrow [1977]) provided any evidence for linkage. An association study, carried out within a group of 91 unrelated schizophrenic patients from Rouen and 91 matched control subjects, examined a 40 base-pair repeat polymorphism located in the 3' nontranslated end of the DAT mRNA. There was no significant difference in allelic or genotypic frequencies between the two groups. These results exclude any substantial involvement of the DAT gene in the pathogenesis of schizophrenia in the population studied.

Adult↗
PubMed1995

Negative symptoms in schizophrenia: their evolution during an acute phase.

Whereas the instability of positive symptoms over time is well recognized, the instability of negative symptoms is still debated. This controversy could be due to the fact that different negative symptoms have been studied in different phases of schizophrenia. We, therefore, hypothesized that some negative symptoms would improve whereas others would remain perfectly stable during the remission of the acute phase of illness. We further hypothesized that the changes in these negative symptoms would be linked to changes in other domains such as extrapyramidal, depressive and positive symptomatology. A broadly defined sample of schizophrenic patients was evaluated at admission and discharge of the hospital with the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS), the Montgomery and Asberg Depression Rating Scale (MADRS) and the Extrapyramidal Symptoms Rating Scale (ESRS). Doses of antipsychotic medications were converted into chlorpromazine-equivalents. Fifty-seven patients (mean age 40.3 years old) were included in the sample and followed-up during their hospitalization. All the sub-scores of the SANS-SAPS decreased significantly but 4 items of the SANS belonging to the affective flattening subscale (unchanging facial expression, decreased spontaneous movements, paucity of expressive gestures and lack of vocal inflections) and one item belonging to the alogia subscale (poverty of speech) did not vary significantly, showing the necessity of taking into account the individual items of the SANS rather than the subscale scores to evaluate the course of negative symptoms. Changes in all the SANS subscores except the alogia subscore were associated with variations in scores of other scales. The change in attentional subscores was positively correlated to the change in the positive formal thought disorder subscores, probably because both belong to the same syndrome. The change in affective flattening subscores was associated with changes in depressive and akinetic scores and 28% of the variance of the change in the affective flattening subscores was explained by the change in the MADRS scores. Changes in avolition-apathy and anhedonia subscores were also associated with changes in MADRS scores but not with the change in akinesia scores.

Acute Disease↗
PubMed1995

A rare allele of a microsatellite located in the tyrosine hydroxylase gene found in schizophrenic patients.

We investigated the frequency of a rare variant of a common microsatellite tetrarepeat allele in the tyrosine hydroxylase gene in 2 independent ethnic groups of schizophrenic patients and their matched controls. In a French population we found the rare variant allele in 5 of 94 (5%) unrelated chronic schizophrenic patients and in none of 145 unaffected controls, thus yielding a significant association (p < 0.01) between schizophrenia and the tyrosine hydroxylase gene. Similarly, in a replication study, we found the rare allele in 4 of 44 (9%) unrelated chronic schizophrenic patients and in none of 44 unaffected controls in a Tunisian population. Albeit the reason of this association is at the moment unknown, it is possible that this polymorphism in the tyrosine hydroxylase gene may be involved in the regulation of its activity.

Adult↗
PubMed1995

[Depressive symptoms and negative symptoms during schizophrenia].

Taking into account the wellknown frequency of depressive and extrapyramidal symptoms in schizophrenia and the rare studies about their evolution, several questions can be raised: How do these different symptoms move? Are there specific characters of each of them? First, stability of negative symptoms evaluated by the Scale for the Assessment of Negative Symptoms (SANS) was studied among 57 schizophrenic patients at admission and at discharge. The course of negative symptoms was compared to that of depressive MADRS (Montgomery et Asberg Depression Rating Scale) and akinetic symptoms (Extrapyramidal Symptom Rating Scale). All the subscores of the SANS decreased significantly but 4 items belonging to the affective flattening subscale and one item belonging to the alogia subscale did not vary significantly, showing the necessity of taking into account the individual items of the SANS rather than the subscale scores to evaluate the course of negative symptoms. Changes in all the SANS subscores except the alogia and anhedonia subscores were associated with variations in scores of other scales. Correlations between the changes of negative symptoms and the changes of depressive symptoms showed the necessity to do more specific scales, for example, scales for depression in schizophrenia. Langlois-Théry et al. (1994) evaluated among 53 schizophrenic patients stabilized with neuroleptic treatment, depressive symptomatology with Echelle de Ralentissement Dépressif (ERD, Widlöcher, 1983) and MADRS, negative symptomatology (Positive and Negative Syndrome Scale) and akinesia (ESRS), to determinate whether ERD composed of 3 subscores (motor, ideic and subjective) could be able to evaluate the depressive symptomatology, independently of the measures of negative and akinetic symptomatology.(ABSTRACT TRUNCATED AT 250 WORDS)

Arousal↗
PubMed1995

[Identification of subgroups of schizophrenic patients by a typological analysis].

The existence of two subtypes of schizophrenia (positive and negative) is well established. The evidence in favour of other subtypes, in particular a disorganized subtype, is still the subject of some debate. Therefore, the aim of the study was to investigate the possibility of further subtypes of schizophrenia by applying a Ward's method of cluster analysis with the Positive And Negative Syndrome Scale (PANSS) scores in 138 schizophrenic patients. The results from the cluster analysis suggested the existence of at least four sub-types of schizophrenia, positive, negative, mixed and disorganized. Evidence for the validity of these subtypes was provided by the observed differences between the clusters on a number of clinical characteristics. Thus, the negative-positive dichotomy in schizophrenia is an oversimplification, and the existence of a more complex structure needs to be taken into account in future research.

Acute Disease↗
PubMed1994

A comparison of plasma homovanillic acid in the deficit and nondeficit subtypes of schizophrenia.

Plasma homovanillic acid (pHVA) was measured over a 13 hr-period in 16 DMS-III-R schizophrenic patients, all treated with neuroleptic drugs and in a stable clinical and therapeutic status for the preceeding 12 months. Patients were categorized into deficit (n = 9) and nondeficit (n = 7) forms of schizophrenia according to the Schedule for the Deficit Syndrome (SDS) criteria. As compared to the nondeficit group, deficit patients display significantly lower mean pHVA concentrations from 9 AM to 12 AM and a lack of diurnal variations. None of the demographic, clinical, and therapeutic variables can explain these biological differences. These data suggest a specific biochemical basis for the deficit syndrome of schizophrenia as defined by the SDS criteria, that is, primary, enduring, negative symptoms.

Adult↗
PubMed1994

Genetic study of dopamine D1, D2, and D4 receptors in schizophrenia.

The goal of this study was to define precisely the involvement of the dopamine D1, D2, and D4 receptor genes in the etiology of schizophrenia. A linkage analysis using the lod score method was performed in 37 families originating from France (n = 14) and from the Island of La Réunion in the Indian Ocean (n = 23). No evidence of linkage between schizophrenia and genetic markers located at these loci was found. A simulation study was carried out to gauge the significance of these results. The conclusions of a nonparametric linkage test (i.e., the affected pedigree member method) were equally negative. For each genetic marker, an allelic association with the disease was also sought: 80 unrelated patients and 80 healthy control subjects were tested, and no significant association was found. These results, which are in agreement with those obtained by other groups, do not support the involvement of the dopamine D1, D2, and D4 receptor genes in the pathogenesis of schizophrenia.

Female↗
PubMed1994

No major role for the dopamine D2 receptor Ser-->Cys311 mutation in schizophrenia.

A new structural polymorphism (Ser311/Cys311) in the dopamine D2 receptor (DRD2) gene has recently been reported to be associated with schizophrenia, particularly in patients with a positive family history of schizophrenia (Arinimi et al., 1994). However these findings remain controversial (Asherson et al., 1994; Nanko et al., 1994; Nöthen et al., 1994; Shaikh et al., 1994). Thus we investigated the role of the Cys311 mutation in schizophrenia using both association and family studies. First, we screened for the Cys311 mutation in 113 unrelated Caucasian schizophrenics (mean age 42 +/- 0.6; 34 females and 79 males) including 25 familial cases, and 184 unrelated controls (mean age 49 +/- 0.5, 74 females and 110 males) free of any psychiatric disorders. Diagnoses were ascertained according to DSM-III criteria (Campion et al., 1994). All patients and controls were native to the area of Rouen.

Alleles↗
PubMed1993

Relationship between depressive and positive symptoms in schizophrenia.

The aim of this study was to investigate the relationship between depressive and positive symptoms, two positive symptom using scales (PANSS and SAPS) in samples defined by three schizophrenic diagnostic systems (DSMIII-R, ICD9 and Langfeldt) at difference phases of the illness and in taking into account the negative and extrapyramidal symptoms and the doses of neuroleptics. With both scales, correlations between depressive and positive symptoms were significantly negative in two diagnostic subgroups (DSMIII-R and Langfeldt) in the acute phase. These correlations were also significant when negative symptoms, subjective extrapyramidal signs and the doses of neuroleptics were partialled out. Only the extrapyramidal physician's score was intercorrelated with positive and negative symptoms. Among the positive symptoms, 'conceptual disorganization' (or 'positive formal thought disorder') and 'suspiciousness/persecution' were especially correlated negatively with depression. At the post-acute phase or at the residual phase, no significant correlation between depressive and positive symptoms was found in any diagnostic subgroup. These results show the necessity of taking into account the phase of illness and the diagnostic criteria in order to study depression in schizophrenia.

Adult↗
PubMed1992

Amisulpride versus bromocriptine in infantile autism: a controlled crossover comparative study of two drugs with opposite effects on dopaminergic function.

An alteration of dopaminergic (DA) function much more complex than simple hyperactivity has been evoked in infantile autism. We therefore compared the clinical efficacy of a DA antagonist (amisulpride) and a DA agonist (bromocriptine) in a randomized, double-blind, crossover trial in 9 children with autism, likely severely mentally retarded. Amisulpride acts preferentially on specific autistic symptoms whereas bromocriptine acts more on motor hyperactivity and attention symptoms. These findings raise the specificity of these two drugs which appear to act preferentially on some target symptoms and are consistent with some clinical and pharmacological observations showing a sedative effect with low doses of DA agonists and a stimulant effect with low doses of DA antagonists such as the benzamides.

Adolescent↗