Triphenyltin(IV) Carboxylates with Exceptionally High Cytotoxicity against Different Breast Cancer Cell Lines

Organotin(IV) carboxylates are a class of compounds explored as alternatives to platinum-containing chemotherapeutics due to propitious in vitro and in vivo results, and distinct mechanisms of action. In this study, triphenyltin(IV) derivatives of non-steroidal anti-inflammatory drugs (indomethacin (HIND) and flurbiprofen (HFBP)) are synthesized and characterized, namely [Ph3Sn(IND)] and [Ph3Sn(FBP)]. The crystal structure of [Ph3Sn(IND)] reveals penta-coordination of the central tin atom with almost perfect trigonal bipyramidal geometry with phenyl groups in the equatorial positions and two axially located oxygen atoms belonging to two distinct carboxylato (IND) ligands leading to formation of a coordination polymer with bridging carboxylato ligands. Employing MTT and CV probes, the antiproliferative effects of both organotin(IV) complexes, indomethacin, and flurbiprofen were evaluated on different breast carcinoma cells (BT-474, MDA-MB-468, MCF-7 and HCC1937). [Ph3Sn(IND)] and [Ph3Sn(FBP)], unlike the inactive ligand precursors, were found extremely active towards all examined cell lines, demonstrating IC50 concentrations in the range of 0.076–0.200 µM. Flow cytometry was employed to examine the mode of action showing that neither apoptotic nor autophagic mechanisms were triggered within the first 48 h of treatment. However, both tin(IV) complexes inhibited cell proliferation potentially related to the dramatic reduction in NO production, resulting from downregulation of nitric oxide synthase (iNOS) enzyme expression.

Synthesis, Crystallographic Structure, Theoretical Analysis, Molecular Docking Studies, and Biological Activity Evaluation of Binuclear Ru(II)-1-Naphthylhydrazine Complex

Ruthenium(II)-arene complexes have gained significant research interest due to their possible application in cancer therapy. In this contribution two new complexes are described, namely [{RuCl(η⁶-p-cymene)}₂(μ-Cl)(μ-1-N,N'-naphthyl)]X (X = Cl, 1; PF₆, 2), which were fully characterized by IR, NMR, and elemental microanalysis. Furthermore, the structure of 2 in the solid state was determined by a single crystal X-ray crystallographic study, confirming the composition of the crystals as 2·2MeOH. The Hirshfeld surface analysis was employed for the investigation of interactions that govern the crystal structure of 2·2MeOH. The structural data for 2 out of 2·2MeOH was used for the theoretical analysis of the cationic part [{RuCl(η⁶-p-cymene)}₂(μ-Cl)(μ-1-N,N'-naphthyl)]⁺ (2a) which is common to both 1 and 2. The density functional theory, at B3LYP/6-31+G(d,p) basis set for H, C, N, and Cl atoms and LanL2DZ for Ru ions, was used for the optimization of the 2a structure. The natural bond orbital and quantum theory of atoms in molecules analyses were employed to quantify the intramolecular interactions. The reproduction of experimental IR and NMR spectra proved the applicability of the chosen level of theory. The binding of 1 to bovine serum albumin was examined by spectrofluorimetry and molecular docking, with complementary results obtained. Compound 1 acted as a radical scavenger towards DPPH^• and HO^• radicals, along with high activity towards cancer prostate and colon cell lines.

Does filter-aided sample preparation provide sufficient method linearity for quantitative plant shotgun proteomics?

Due to its outstanding throughput and analytical resolution, gel-free LC-based shotgun proteomics represents the gold standard of proteome analysis. Thereby, the efficiency of sample preparation dramatically affects the correctness and reliability of protein quantification. Thus, the steps of protein isolation, solubilization, and proteolysis represent the principal bottleneck of shotgun proteomics. The desired performance of the sample preparation protocols can be achieved by the application of detergents. However, these compounds ultimately compromise reverse-phase chromatographic separation and disrupt electrospray ionization. Filter-aided sample preparation (FASP) represents an elegant approach to overcome these limitations. Although this method is comprehensively validated for cell proteomics, its applicability to plants and compatibility with plant-specific protein isolation protocols remain to be confirmed. Thereby, the most important gap is the absence of the data on the linearity of underlying protein quantification methods for plant matrices. To fill this gap, we address here the potential of FASP in combination with two protein isolation protocols for quantitative analysis of pea (Pisum sativum) seed and Arabidopsis thaliana leaf proteomes by the shotgun approach. For this aim, in comprehensive spiking experiments with bovine serum albumin (BSA), we evaluated the linear dynamic range (LDR) of protein quantification in the presence of plant matrices. Furthermore, we addressed the interference of two different plant matrices in quantitative experiments, accomplished with two alternative sample preparation workflows in comparison to conventional FASP-based digestion of cell lysates, considered here as a reference. The spiking experiments revealed high sensitivities (LODs of up to 4 fmol) for spiked BSA and LDRs of at least 0.6 × 10². Thereby, phenol extraction yielded slightly better recoveries, whereas the detergent-based method showed better linearity. Thus, our results indicate the very good applicability of FASP to quantitative plant proteomics with only limited impact of the protein isolation technique on the method's overall performance.

Mesoporous Silica Nanoparticles Enhance the Anticancer Efficacy of Platinum(IV)-Phenolate Conjugates in Breast Cancer Cell Lines

The main reasons for the limited clinical efficacy of the platinum(II)-based agent cisplatin include drug resistance and significant side effects. Due to their better stability, as well as the possibility to introduce biologically active ligands in their axial positions constructing multifunctional prodrugs, creating platinum(IV) complexes is a tempting strategy for addressing these limitations. Another strategy for developing chemotherapeutics with lower toxicity relies on the ability of nanoparticles to accumulate in greater quantities in tumor tissues through passive targeting. To combine the two approaches, three platinum(IV) conjugates based on a cisplatin scaffold containing in the axial positions derivatives of caffeic and ferulic acid were prepared and loaded into SBA-15 to produce the corresponding mesoporous silica nanoparticles (MSNs). The free platinum(IV) conjugates demonstrated higher or comparable activity with respect to cisplatin against different human breast cancer cell lines, while upon immobilization, superior antiproliferative activity with markedly increased cytotoxicity (more than 1000-fold lower IC₅₀ values) compared to cisplatin was observed. Mechanistic investigations with the most potent conjugate, cisplatin-diacetyl caffeate (1), and the corresponding MSNs (SBA-15|1) in a 4T1 mouse breast cancer cell line showed that these compounds induce apoptotic cell death causing strong caspase activation. In vivo, in BALB/c mice, 1 and SBA-15|1 inhibited the tumor growth while decreasing the necrotic area and lowering the mitotic rate.

Albatrellus confluens (Alb. & Schwein.) Kotl. & Pouz.: Natural Fungal Compounds and Synthetic Derivatives with In Vitro Anthelmintic Activities and Antiproliferative Effects against Two Human Cancer Cell Lines

Neglected tropical diseases affect the world's poorest populations with soil-transmitted helminthiasis and schistosomiasis being among the most prevalent ones. Mass drug administration is currently the most important control measure, but the use of the few available drugs is giving rise to increased resistance of the parasites to the drugs. Different approaches are needed to come up with new therapeutic agents against these helminths. Fungi are a source of secondary metabolites, but most fungi remain largely uninvestigated as anthelmintics. In this report, the anthelmintic activity of Albatrellus confluens against Caenorhabditis elegans was investigated using bio-assay guided isolation. Grifolin (1) and neogrifolin (2) were identified as responsible for the anthelmintic activity. Derivatives 4-6 were synthesized to investigate the effect of varying the prenyl chain length on anthelmintic activity. The isolated compounds 1 and 2 and synthetic derivatives 4-6, as well as their educts 7-10, were tested against Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum. Prenyl-2-orcinol (4) and geranylgeranyl-2-orcinol (6) showed promising activity against newly transformed schistosomula. The compounds 1, 2, 4, 5, and 6 were also screened for antiproliferative or cytotoxic activity against two human cancer lines, viz. prostate adenocarcinoma cells (PC-3) and colorectal adenocarcinoma cells (HT-29). Compound 6 was determined to be the most effective against both cell lines with IC₅₀ values of 16.1 µM in PC-3 prostate cells and 33.7 µM in HT-29 colorectal cells.

Anthelmintic Activity and Cytotoxic Effects of Compounds Isolated from the Fruits of Ozoroa insignis Del. (Anacardiaceae)

Ozoroa insignis Del. is an ethnobotanical plant widely used in traditional medicine for various ailments, including schistosomiasis, tapeworm, and hookworm infections. From the so far not investigated fruits of Ozoroa insignis, the anthelmintic principles could be isolated through bioassay-guided isolation using Caenorhabditis elegans and identified by NMR spectroscopic analysis and mass spectrometric studies. Isolated 6-[8(Z)-pentadecenyl] anacardic (1), 6-[10(Z)-heptadecenyl] anacardic acid (2), and 3-[7(Z)-pentadecenyl] phenol (3) were evaluated against the 5 parasitic organisms Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum, which mainly infect humans and other mammals. Compounds 1-3 showed good activity against Schistosoma mansoni, with compound 1 showing the best activity against newly transformed schistosomula with 50% activity at 1µM. The isolated compounds were also evaluated for their cytotoxic properties against PC-3 (human prostate adenocarcinoma) and HT-29 (human colorectal adenocarcinoma) cell lines, whereby compounds 2 and 3 showed antiproliferative activity in both cancer cell lines, while compound 1 exhibited antiproliferative activity only on PC-3 cells. With an IC50 value of 43.2 µM, compound 3 was found to be the most active of the 3 investigated compounds.

Cisplatin-cyclooxygenase inhibitor conjugates, free and immobilised in mesoporous silica SBA-15, prove highly potent against triple-negative MDA-MB-468 breast cancer cell line

For the development of anticancer drugs with higher activity and reduced toxicity, two approaches were combined: preparation of platinum(IV) complexes exhibiting higher stability compared to their platinum(II) counterparts and loading them into mesoporous silica SBA-15 with the aim to utilise the passive enhanced permeability and retention (EPR) effect of nanoparticles for accumulation in tumour tissues. Three conjugates based on a cisplatin scaffold bearing the anti-inflammatory drugs naproxen, ibuprofen or flurbiprofen in the axial positions (1, 2 and 3, respectively) were synthesised and loaded into SBA-15 to afford the mesoporous silica nanoparticles (MSNs) SBA-15|1, SBA-15|2 and SBA-15|3. Superior antiproliferative activity of both free and immobilised conjugates in a panel of four breast cancer cell lines (MDA-MB-468, HCC1937, MCF-7 and BT-474) with markedly increased cytotoxicity with respect to cisplatin was demonstrated. All compounds exhibit highest activity against the triple-negative cell line MDA-MB-468, with conjugate 1 being the most potent. However, against MCF-7 and BT-474 cell lines, the most notable improvement was found, with IC₅₀ values up to 240-fold lower than cisplatin. Flow cytometry assays clearly show that all compounds induce apoptotic cell death elevating the levels of both early and late apoptotic cells. Furthermore, autophagy as well as formation of reactive oxygen species (ROS) and nitric oxide (NO) were elevated to a similar or greater extent than with cisplatin.

Antitumor potential of cisplatin loaded into SBA-15 mesoporous silica nanoparticles against B16F1 melanoma cells: in vitro and in vivo studies

CP (cisplatin) and mesoporous silica SBA-15 (Santa Barbara amorphous 15) loaded with CP (→SBA-15|CP) were tested in vitro and in vivo against low metastatic mouse melanoma B16F1 cell line. SBA-15 only, as drug carrier, is found to be not active, while CP and SBA-15|CP revealed high cytotoxicity in lower μM range. The activity of SBA-15|CP was found similar to the activity of CP alone. Both CP and SBA-15|CP induced inhibition of cell proliferation (carboxyfluorescein succinimidyl ester - CFSE assay) along with G2/M arrest (4',6-diamidino-2-phenylindole - DAPI assay). Apoptosis (Annexin V/ propidium iodide - PI assay), through caspase activation (apostat assay) and nitric oxide (NO) production (diacetate(4-amino-5-methylamino-2',7'-difluorofluorescein-diacetat) - DAF FM assay), was identified as main mode of cell death. However, slight elevated autophagy (acridine orange - AO assay) was detected in treated B16F1 cells. CP and SBA-15|CP did not affect production of ROS (reactive oxygen species) in B16F1 cells. Both SBA-15|CP and CP induced in B16F1 G2 arrest and subsequent senescence. SBA-15|CP, but not CP, blocked the growth of melanoma in C57BL/6 mice. Moreover, hepato- and nephrotoxicity in SBA-15|CP treated animals were diminished in comparison to CP confirming multiply improved antitumor potential of immobilized CP. Outstandingly, SBA-15 boosted in vivo activity and diminished side effects of CP.

Need for systematic screening for IGD in adolescent psychiatric inpatients

Psychiatric comorbidities are frequent in adolescents with internet gaming disorder (IGD). In contrast, the proportion of IGD among adolescents hospitalized for a psychiatric disorder has not been documented yet. In addition, parental ratings of IGD could be useful for diagnosis, but very few data exist on this issue. The objectives of this study were to: (1) assess the prevalence of IGD among adolescent psychiatric inpatients, using the Ten-Item Internet Gaming Disorder Test (IGDT-10), and (2) assess the parental version developed for this study (IGDT-10-P). A total of 102 patients, aged from 12 to 17 years old, were included from four psychiatric units of the French region Auvergne-Rhône-Alpes, during a 6-month inclusion period. Adolescents completed the IGDT-10 while one of their parents completed the IGDT-10-P. The inclusion rate among the eligible population was 57.95%. The prevalence of IGD in the sample, based on the IGDT-10 and IGDT-10-P, was 6.00% and 12.79%, respectively. Psychometric features of the IGDT-10-P indicated excellent internal consistency, a good model fit to the one factor model in confirmatory factor analysis, a strong correlation with gaming time, and a moderate correlation with the IGDT-10. Our results support the need for a systematic screening of IGD among adolescents hospitalized for a psychiatric disorder. Future studies should aim to confirm and explain the prevalence gap between self- and parent-reported criteria.

Cichorins D-F: Three New Compounds from Cichorium intybus and Their Biological Effects

Cichorium intybus L., (chicory) is employed in various traditional medicines to treat a wide range of diseases and disorders. In the current investigation, two new naphthalane derivatives viz., cichorins D (1) and E (2), along with one new anthraquinone cichorin F (3), were isolated from Cichorium intybus. In addition, three previously reported compounds viz., β-sitosterol (4), β-sitosterol β-glucopyranoside (5), and stigmasterol (6) were also isolated from Cichorium intybus. Their structures were established via extensive spectroscopic data, including 1D (1H and 13C) and 2D NMR (COSY, HSQC and HMBC), and ESIMS. Cichorin E (2) has a weak cytotoxic effect on breast cancer cells (MDA-MB-468: IC50: 85.9 µM) and Ewing's sarcoma cells (SK-N-MC: IC50: 71.1 µM); cichorin F (3) also illustrated weak cytotoxic effects on breast cancer cells (MDA-MB-468: IC50: 41.0 µM and MDA-MB-231: IC50: 45.6 µM), and SK-N-MC cells (IC50: 71.9 µM). Moreover compounds 1-3 did not show any promising anthelmintic effects.

Predictors of response to repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depressive disorder

Repetitive transcranial magnetic stimulation (rTMS), based on the principle of electromagnetic induction, consists of applying series of magnetic impulses to the cerebral cortex so as to modulate neurone activity in a target zone. This technique, still experimental, could prove promising in the field of psychiatry, in particular for the treatment of major depressive disorder. It is important for the clinician to be able to assess the response potential of a given patient to rTMS, and this among other things requires relevant predictive factors to be available. This review of the literature aims to determine and analyse reported predictive factors for therapeutic response to rTMS treatment in major depressive disorder. Different parameters are studied, in particular age, the severity of the depressive episode, psychological dimensions, genetic factors, cerebral blood flows via cerebral imagery, and neuronavigation. The factors found to be associated with better therapeutic response were young age, low level of severity of the depressive episode, motor threshold intensity over 100%, more than 1000 stimulations per session, more than 10 days treatment, L/L genotype on the 5-HTTLPR transporter gene, C/C homozygosity on the promotor regions of the 5-HT1A receptor gene, Val/Val homozygosity on the BDNF gene, cordance analyses by EEG, and finally the accurate localisation provided by neuronavigation. The authors conclude that investigations in larger patient samples are required in the future, and that the work already achieved should provide lines of approach for the coming experimental studies.

Comment mieux valoriser notre activité en psychiatrie de liaison ?

La cooccurrence des troubles somatiques et psychiatriques est très fréquente chez les patients admis à l’hôpital général. Il en découle des augmentations des risques de morbi-mortalité et des surcoûts liés à la complexité des soins [1]. Ces patients nécessitent des prises en charge multidisciplinaire ou le rôle du psychiatre de liaison-consultation joue un rôle important. Les effets bénéfiques de ces prises en charge a été démontré notamment en termes de durée moyenne de séjour. Cependant, ces études soulèvent beaucoup d’interrogation notamment concernant le critère principal d’évaluation. Ainsi par exemple certaines études, se sont intéressées au niveau de satisfaction des praticiens somaticiens et des patients ainsi qu’à leurs attentes. Ces difficultés découlent également du fait que les classifications psychiatriques usuelles (DSM et CIM) apparaissent souvent comme insuffisantes pour décrire les comorbidités psychiatriques chez les patients hospitalisés à l’hôpital général [2]. Certains groupes d’experts ont par conséquent proposé quelques catégories nosographiques plus proches de la réalité de la pratique de la psychiatrie de liaison [3]. Dans cette revue, seront abordés les éléments de valorisation de l’activité de psychiatrie de liaison. Ces éléments sont : le bien-être des patients, l’intégration des psychiatres dans les équipes multidisciplinaires et les aspects médico-économiques.

Treatment of shizophrenic patients and rTMS

INTRODUCTION

schizophrenia (SCH) is a heterogeneous syndrome characterized by positive and negative symptoms. Despite appropriate medication, about 1/4 of patients suffer for refractory positive and/or negative symptoms, which are associated with functional handicap, increase of duration and of the number of hospitalizations. Numerous studies have suggested that the pathophysiology of auditory hallucinations (AH) is related to a hyper activity of the left temporoparietal cortex (TPC). On the other hand, negative symptoms are associated with a prefrontal hypoactivity and the efficiency of pharmacological treatments is frequently partial. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation tool with excellent tolerability and safety. Given its hypothesized mechanisms of action and the clinical beneficial effects obtained in several types of pathology (Aleman et al. 2007), the efficacy of rTMS has been investigated for drug-resistant SCH symptoms.

OBJECTIVE

our objective is to expose the knowledge concerning the rTMS use in the treatment of these symptoms and to purpose a critical analysis of these data.

METHOD

a systematic review of the literature has been conducted using NIH Pubmed. The following search terms were used: TMS - rTMS - Schizophrenia - negative symptoms - hallucinations.

RESULTS

concerning the treatment of AH, 16 publications and 4 meta analyses were selected. For the negative symptoms, we retained 16 studies and 3 meta analyses. The most extensively investigated application for rTMS in SCH is the use of low-frequency stimulation to the left TPC with the aim to improve AH symptomatology. When compared to sham, this type of acute course of rTMS has been proven to induce a substantial and significant reduction in AH. But this effect does not seem long-lasting and maintenance protocols must be developed. Concerning negative symptoms, the results are less solid but we find some works which demonstrate an improvement of these symptoms while various stimulation parameters were used. Recently, new parameters of stimulation in particular the theta burst stimulation have permitted us to obtain larger effects with longer duration. The interest of these new parameters will be discussed here.

CONCLUSION

overall, rTMS studies have demonstrated some promise in the treatment of SCH. However, more research is required to enhance rTMS efficacy and increase its beneficial effect duration and to test new therapeutic strategies in this topic.

Comorbidity between temporal lobe epilepsy and depression: a [18F]MPPF PET study

Brain and brainstem changes of serotoninergic 5-hydroxytryptophan (5-HT)(1A) receptor density have been reported in patients with major depressive disorder as well as in patients with temporal lobe epilepsy (TLE), using PET and the selective antagonist radiotracers [(11)C]WAY-100635 or [(18)F]FC-WAY. We used a distinct 5-HT(1A) antagonist, [(18)F]MPPF, whose binding potential depends on both receptor density and extracellular serotonin concentration, in 24 patients with drug-resistant TLE and MRI evidence of hippocampal sclerosis but without prior antidepressant exposure. Their Beck Depression Inventory (BDI-2) score ranged from 0 to 34, with nine patients having a score >11. We used a simplified reference tissue model, statistical parametric mapping and anatomical regions of interest (ROIs) to correlate parametric images of [(18)F]MPPF BP with the total BDI score and its four subclasses. The total BDI score, as well as symptoms of psychomotor anhedonia and negative cognition, correlated positively with [(18)F]MPPF BP in the raphe nuclei and in the insula contralateral to seizure onset, whereas somatic symptoms correlated positively with [(18)F]MPPF binding potential in the hippocampal/parahippocampal region ipsilateral to seizure onset, the left mid-cingulate gyrus and the inferior dorsolateral frontal cortex, bilaterally. We confirm an association of depressive symptoms in TLE patients with changes of the central serotoninergic pathways, in particular within the raphe nuclei, insula, cingulate gyrus and epileptogenic hippocampus. These changes are likely to reflect lower extracellular serotonin concentration in more depressed patients, with an upregulation of receptors a less likely alternative.

Efficacité de la stimulation magnétique transcrânienne (rTMS) dans le traitement de la dépression : revue de la littérature

INTRODUCTION

In 1985, Barker et al. showed that it was possible to stimulate both nerves and brain using external magnetic stimulation without significant pain. During the past 10 years, therapeutic effects of repeated Transcranial Magnetic Stimulation (rTMS) have been widely studied in psychiatry and its efficacy has been demonstrated in the treatment of major depressive disorders, particularly as an alternative to electroconvulsivotherapy (ECT). Facing the large range of studies, we found necessary to propose an up-to-date review in French of the methodological and therapeutic variations among them.

METHOD

Based on an exhaustive consultation of Medline data and the Avery-George-Holtzheimer Database of rTMS Depression-Studies, supplemented by a manual research, only works evaluating the therapeutic efficacy of rTMS on depressive symptoms were retained, excluding all studies exclusively investigating the stimulation parameters or the tolerance as well as case reports.

RESULTS

Out the 66 available reports we retained 30 studies. After a description of the main results of these 30 studies, several elements of the 66 will be discussed. Open studies demonstrated that short courses rTMS (5 to 10 sessions) produced a decrease in the mean Hamilton Depression Ratting Scale (HDRS) scores, although significant remission of depression in individuals was rare. Most authors had used high frequency rTMS applied to the left Dorso Lateral Prefrontal Cortex (left DLPFC). However, low frequency rTMS applied to the right DLPFC was also followed by significant reduction of HDRS scores. Parallel arm, double blind versus placebo studies are designed to clarify the therapeutic efficacy of rTMS therapy but conclude in contradicting results. Literature data globally confirms a greater efficacy of rTMS compared to placebo (37% responders in the active group vs 20% in the sham). This efficacy could in fact be even greater because the sham procedure is disputable in most studies. Indeed, positioning rTMS coil at 45 or 90 from the scalp may not represent an accurate sham procedure and the use of real sham coil is to be recommended. Only one study has suggested that associating rTMS and ECT could decrease the number of general anesthesia required. Therapeutic efficacy has been shown by either inhibiting the right DLPFC or by stimulating the left DLPFC, although some patients exhibit paradoxical responses. High frequency rTMS (>5 Hz) increases cortical excitability and metabolism, while low-frequency rTMS stimulation ( 1 Hz) has the opposite effect. Other parameters are: relevant: intensity (from 80 to 110% of motor threshold), total number of stimulations (from 120 to 2 000) and total number of rTMS sessions (from 5 to 20). As suggested in most recent studies, higher-intensity pulses, higher number of stimulation or longer treatment courses may be more effective. Greater responsiveness to rTMS may be predicted by several patients' factors, including the absence of psychosis, younger age and previous response to rTMS therapy.

DISCUSSION

Conclusions on these factors and others, such as the importance of anatomically accurate coil placement and the distance from the coil to the brain, await further investigation. Despite heterogeneity of these reports according to methodology and treatment parameters, the antidepressive properties of rTMS now appear obvious, opening interesting prospects, in particular in the treatment of pharmacoresistant major depressive patients and, we hope, administered as adjuvant therapy in non-resistant depression.

CONCLUSION

Thus, many questions remain unanswered concerning the optimal stimulation parameters, privileged indications and maintenance sessions. This justifies the development of structured evaluation trials on larger samples.

Impact de la remédiation cognitive dans la schizophrénie sur les stratégies de résolution de problèmes et l’autonomie sociale : utilisation du logiciel REHACOM®

INTRODUCTION

Despite recent developments, the impact of pharmacotherapy on social autonomy and interpersonal problem solving skills in patients with schizophrenia remains limited, with consequences in terms of socio-professional functioning. Indeed, independently of the positive, negative and/or disorganization symptoms, functional deficits in patients with schizophrenia rely mainly on various cognitive impairments.

OBJECTIVES

To determine the impact of a new Cognitive Remediation Strategy on interpersonal problem solving skills, social autonomy and symptoms in patients with schizophrenia.

METHODS

Thirty patients with schizophrenia were enrolled in a program consisting of 14 training sessions of 4 cognitive functions (attention/concentration, topological memory, logical reasoning, executive functions) using the REHACOM software. Measurements of attention (Continuous Performance Test, CPT), memory (Rivermead Behavioural Memory Test, RBMT) and executive functions (Wisconsin Card Sorting Test, WCST) as well as interpersonal problem solving skills (Assessment of Interpersonal Problem-Solving Skills, AIPSS) and social autonomy (Social Autonomy Scale, EAS) and finally schizophrenia symptoms (Positive And Negative Syndrom Scale, PANSS) were undertaken at the beginning and the end of the 14 remediation meetings.

RESULTS

Cognitive functions, interpersonal problems solving skills, social autonomy and symptoms were significantly improved by the Cognitive Remediation Strategy.

CONCLUSION

Our results confirm the therapeutic impact of a Cognitive Remediation Strategy among 30 schizophrenic patients stabilised on clinical, therapeutic and functional levels. The question of the long-term maintenance of such improvements still requires further investigation.

Repetitive transcranial magnetic stimulation does not potentiate antidepressant treatment

In a double blind controlled study, rTMS results in a similar antidepressant effect to sham in combination with paroxetine. Both groups had the same delay in scale's scores improvement. rTMS seems not to be efficient as an add-on treatment to pharmacological medication in non-resistant major depression.

[Pharmacological modulation of the effects induced by ketamine at subanesthetic doses]

The similarity between ketamine effects and endogenous psychoses has created interest in the capacity of antipsychotic medications to block ketamine effects. In healthy subjects, a sub-anaesthetic single dose of lorazepam, typical neuroleptics, such as haloperidol, and atypical neuroleptics, such as clozapine and olanzapine, failed to block ketamine-induced positive and negative symptoms resembling schizophrenia. However, haloperidol is able to decrease ketamine-induced impairment in executive cognitive functions. Recently, lamotrigine reduced ketamine-induced psychotic symptoms, perceptual alterations, and cognitive impairments. In schizophrenic subjects, single doses of olanzapine do not decrease the effects of ketamine. However, long term treatment with clozapine has been reported to decrease ketamine-induced positive symptoms. Pharmacological modulation of the effects of NMDA receptor antagonists, such as ketamine, may lead to development of novel therapeutic agents for psychiatric illnesses such as schizophrenia.

Poor performance in smooth pursuit and antisaccadic eye-movement tasks in healthy siblings of patients with schizophrenia

This study examines the area of eye movement dysfunctions as an indicator of vulnerability to schizophrenia. Eye movement performance was investigated with three different paradigms: Smooth Pursuit Eye Movements (SPEM); Visually Guided Saccades (VGS); and Antisaccades (AS) in 21 clinically stable patients with schizophrenia, 21 of their healthy, biological full siblings and 21 healthy control subjects. The three groups did not differ on VGS performance, whereas both patients and their siblings showed lower SPEM gain, an increased catch-up Saccades (CUS) rate, reduced AS accuracy and an increased number of AS errors in comparison to control subjects. In addition, patients with schizophrenia exhibited increased AS latency. Among the patients with schizophrenia, eye movement abnormalities did not correlate with age, gender, clinical state or duration of illness. These data suggest that abnormalities of SPEM and AS may represent neurobiological markers of the vulnerability to schizophrenia in individuals at high genetic risk for the disease.

Neuropsychological deficit in siblings discordant for schizophrenia

This study was aimed, first, at detecting neuropsychological markers that assess vulnerability to schizophrenia in siblings of patients with schizophrenia, and second, at exploring possible relationships between markers. For these purposes, performances were assessed in 18 clinically stabilized patients with schizophrenia, 18 of their unaffected full siblings, and 15 controls on attentional abilities (the Degraded Stimuli-Continuous Performance Task [DS-CPT] and the Span of Apprehension [SOA] task) and on executive functions (the Wisconsin Card Sorting Test [WCST]). Both patients and siblings were impaired on the three tasks, leading to the conclusion that these poor performances may represent markers of genetic vulnerability to schizophrenia. Furthermore, significant relationships were found between DS-CPT and WCST performance in patients only, suggesting a possible implication of prefrontal brain areas for the two tasks. In spite of the lack of similar relationships between DS-CPT and WCST in siblings, this raises the question of a putative role of prefrontal areas in vulnerability to schizophrenia.

[Glutaminergic hypothesis of schizophrenia: clinical research studies with ketamine]

Several lines of evidence suggest that the glutamatergic N-methyl-D-aspartate (NMDA) receptor is involved in schizophrenia pathophysiology. Post-mortem studies have revealed a lower density of glutamatergic receptors in patients with schizophrenia. Other studies of cerebrospinal fluid reported lower levels of glutamate in patients with schizophrenia in healthy comparison subjects. The most compelling evidence is provided by the psychomimetic effects of the NMDA antagonists phencyclidine and ketamine. Recently, much interest has been given to the study related to the role of NMDA receptor in pathophysiology of schizophrenia by administration of sub-anesthetic doses of ketamine. A phencyclidine hydrochloride derivate, ketamine, is a dissociative anesthetic and a non competitive antagonist of the NMDA receptor. In healthy subjects, ketamine produces: 1) positive symptoms of psychosis, such as illusions, thought disorder and delusions; 2) negative symptoms similar to those associated with schizophrenia including blunted emotional responses, emotional detachment, and psychomotor retardation; 3) cognitive impairments, in particular impairments on tests of frontal cortical function including increased distractibility, reduced verbal fluency and poorer performance on the Wisconsin Card Sorting Test. During smooth pursuit eye tracking, ketamine induces nystagmus as well as abnormalities which are among the characteristics of schizophrenia. In patients with schizophrenia, the administration of ketamine produces an activation of their psychotic symptoms, which have striking similarities to symptoms of their usual psychotic episodes. Ketamine effects on memory and other cognitive functions in schizophrenic patients are controversial. The psychomimetic effects of ketamine are transitional, reversible and influenced by time, dose and administration conditions. Susceptibility to the psychotomimetic effects of ketamine is minimal or absent in children and becomes maximal in early adulthood. The similarity between ketamine effects and endogenous psychoses created interest in the capacity of antipsychotic medications to block ketamine effects. Haloperidol failed to block this ketamine-induced psychomimetic effects in healthy subjects and in schizophrenic patients. However, clozapine, the prototype of atypical antipsychotic agents significantly reduced the ketamine-induced increase in positive symptoms in schizophrenic patients. Recently, lamotrigine significantly decreased ketamine-induced positive and negative symptoms in healthy subjects. Brain regions responsible for NMDA-mediated psychosis have not been established. Using positron emission tomography and [18F] fluorodeoxyglucose, the sub-anesthetic ketamine administration produces bilateral increases in metabolic activity in the prefrontal cortex. In a [15O] H2O positron emission tomography study, ketamine selectively increases cerebral blood flow in the anterior cingulate cortex and reduces cerebral blood flow in the hippocampus and primary visual cortex. The mechanism of neuropsychiatric effects of sub-anesthetic ketamine is not clear. A dysfunction in glutamate-dopaminergic interactions has been suggested as a mechanism for these effects of ketamine. Ketamine has been reported to primarily block NMDA receptor complex giving support to a glutamate deficiency hypothesis in schizophrenia. In addition, ketamine caused increases in cortical and striatal synaptic dopamine concentrations. The effects of NMDA receptor antagonist administration are argued to support a neurobiological hypothesis of schizophrenia, which includes pathophysiology within several neurotransmitter systems, manifested in behavioral pathology. Pharmacological modulation of the effects of NMDA receptor antagonists, such as ketamine, may lead to development of novel therapeutic agents for psychiatric illnesses such as schizophrenia.

[Validation of the French version of the Raine Schizotypal Personality Disorder Questionnaire--categorial and dimensional approach to schizotypal personality traits in a normal student population]

Most of existing self-report measures of schizotypal personality assess only few of the nine traits of Schizotypal Personality Disorder (SPD) according to DSM III-R or DSM IV. The Raine's Schizotypal Personality Questionnaire (SPQ) is one of the most widely used questionnaire for SPD diagnosis. This well adapted tool for screening SPD in large samples from general population allows simple and quick evaluations by the mean of 74 items and nine sub-scales exploring DSM IV criteria of the trouble. With the original sample of American students, Raine found SPQ to have high internal reliability (0.91) and reported cutoffs for the top and the bottom ten percents of SPQ scores at respectively 41/74 and 12/74. We reported here the validation study of the French version of the SPQ in a sample of 232 students (males: n = 107; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French version has high internal reliability (SPQ total: Cronbach's alpha = 0.91; SPQ nine subscales: Cronbach's alpha = 0.57 to 0.76). The ten percent high and low cutoff scores on the distribution of SPQ scores are respectively 40/74 and 7/74 for the total sample. However, gender differences are observed: 38/74 and 9/74 for females; 42/74 and 6/74 for males. A Principal Component Analysis (PCA) confirms the high internal reliability. Moreover, PCA evidences a three-factor model of schizotypy reflecting "positive or cognitive-perceptual", "negative or social-interpersonal", and "disorganization" latent factors. These results replicate previous works on the topic with the same instrument.

[Validation of French versions of magical ideation and perceptual aberrations questionnaires]

Chapman and colleagues have developed symptom-oriented scales based on Meehl's manual of schizotypy, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), and the Perceptual Aberration Scale (PAS). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. We reported here the validation study of the MIS and the PAS French versions that we had published previously. This study was conducted in a sample of 233 students (males: n = 108; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French versions of the MIS and the PAS have high internal reliability (MIS: Cronbach's alpha = 0.85; PAS: Cronbach's alpha = 0.88). French norms are given for each of these scales. They are respectively 19/30 for the MIS and 17/35 for the PAS high cutoff scores without any difference when gender was considered. These results are very closed to those found by Chapman and colleagues for University of Wisconsin undergraduate students.

Alteration of event related potentials in siblings discordant for schizophrenia

This study was aimed at confirming that auditory event related potential (ERP) abnormalities are indicators of vulnerability to schizophrenia. Auditory ERP performances were assessed at Fz, Cz, and Pz, with an oddball paradigm, in 21 clinically stable patients with schizophrenia, 21 of their healthy biological full siblings and 21 control subjects. The evoked response did not differ between the three groups on N200 waves. Compared to controls, patients with schizophrenia exhibited reduced amplitudes of N100 and P300, and prolonged latency of P300, while their siblings showed prolonged latency of P200 and P300. Among the patients with schizophrenia, ERP abnormalities did not correlate with age, clinical state, duration of illness or antipsychotic treatments. Although other conditions also accounted for alterations of the same type, ERP abnormalities may represent a neurobiological marker of the genetic vulnerability to schizophrenia, independent of phenotypic expression.

Attentional deficits in patients with schizophrenia and in their non-psychotic first-degree relatives

The aim of this study was to investigate whether non-psychotic relatives of schizophrenic probands have deficits in sustained attention as measured by the Continuous Performance Test, Identical Pairs version (CPT-IP) and whether such deficits are associated with negative schizotypal personality disorders. The study subjects were 23 schizophrenic probands, 45 of their first-degree relatives and 36 normal controls. For each subject, attention was assessed during five conditions (2 standard, 2 slow, 1 easy) of visual stimuli (numbers and shapes). Schizotypy status was determined with the physical anhedonia and social anhedonia scales of Chapman et al. (Chapman, L.J., Chapman, J.P., Raulin, M.L., 1976. Scales for physical and social anhedonia. Journal of Abnormal Psychology 42, 374-382). The CPT-IP sensitive index d' in the standard shape condition was significantly lower in schizophrenics and in their relatives than in controls. For all d' values, the percentage of impaired first-degree relatives was at an intermediate level between patients and control individuals. Furthermore, the schizophrenic probands made more random errors in the standard and in the slow number conditions than the other two groups. None of the schizotypy measures correlated with the CPT-IP deficits. These results suggest that spatial sustained attention deficit may be a vulnerability marker for schizophrenia; however, this deficit and the negative dimension of schizotypal personality disorders may be distinct traits.

Neuropsychological functioning among non-psychotic siblings and parents of schizophrenic patients

Several studies have shown subtle neuropsychological deficits in healthy relatives of schizophrenic patients. However, older relatives and parents have been less frequently assessed than younger adult relatives and siblings. Furthermore, some areas of neuropsychological functioning such as memory and learning have been little studied. Thirty-seven 22-70-year-old non-psychotic parents and siblings of schizophrenic patients were compared to 37 healthy control subjects on a battery of neuropsychological tests (Trail Making, parts A and B, verbal fluency, Wisconsin Card Sorting Test, and four subtests of the Wechsler Memory Scale-Revised: logical memory, design reproduction, verbal paired associates and digit span). Relatives did not differ from control subjects on Wisconsin Card Sorting Test performance and on visual memory, but were significantly impaired on verbal fluency; more subtle deficits were found on Trail Making, part B, digit span and paired associates. A higher proportion of relatives than control subjects showed impairment on verbal fluency and verbal memory. These neuropsychological weaknesseswere present as much in siblings as in parents of schizophrenic patients, and age did not cancel differences between relatives and control subjects. Thus, these subtle deficits seem to be potential phenotypic markers of schizophrenia.

[French translations and adaptations of questionnaires of magical thinking (MIS, Eckblad and Chapman, 1983) and perception disorders (PAS, Chapman et al., 1978)]

Meehl used the term "schizotype" to refer to individuals who possess an underlying vulnerability for schizophrenia. Because of the extremely varying degrees of the schizotype's clinical expression, he recommended assessing schizotypic signs through objective measures rather than clinical judgement. In this way, Chapman et al. have developed symptom-oriented scales based on Meehl's manual, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), the Perceptual Aberration Scale (PAS) and the Impulsive Nonconformity Scale (IN). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. Therefore, the first aim of this report was to offer French translations of the Magical Ideation and the Perceptual Aberration Scales; the agreement of the original authors were obtained for both translated versions and their back translations. The second aim of our study was to establish French norms for each of these scales. The preliminary norms presented here [MIS: 19/30 (for females) and 20/30 (for males); PAS: 18/35 (for both genders)] were obtained by administering both scales to a sample of 134 French students. They are very close to those found by Chapman et al. for University of Wisconsin undergraduate students. We will confirm them with a larger sample of French students.

[Translation and French adaptation of the Raine Schizotypal Personality Questionnaire]

Most of existing self-report measures of schizotypal personality assess only few of the nine traits of schizotypal personality disorder according to DSM III-R or DSM IV. Adrian Raine has developed a self-report scale named "Schizotypal Personality Questionnaire, [SPQ]" to evaluate all these traits. The questionnaire was found to have high sampling validity, high internal reliability [0.91] and test-retest reliability [0.82]. However, the SPQ was still not available in French. Therefore, the first purpose of this report was to offer a French translation of this tool with the agreement of A. Raine for both translated version and its back translation. The second purpose of our study was to establish French norms. The preliminary norms presented here were obtained by administering the SPQ to a sample of 134 French students of both gender (mean age: 20.11 +/- 1.53 years; mean educational level: 13.39 +/- 1.04 years). On that sample, the minimal score was 2/74 and the maximal one 54/74 (mean of the sample: 23.60 +/- 12.09). With the original English study, based on a sample of American students, the cut-offs for the top and the bottom ten percents of SPQ scores were respectively of 41/74 and 12/74. Very close preliminary cut-offs were observed in our own study i.e. respectively 40/74 and 9/74. We will confirm them in a larger sample.

[Vulnerability to schizophrenia. II: Familial status of auditory evoked potential abnormalities]

The existence of a genetic background is well admitted in schizophrenia, but some individuals at genetic risk for that disease could never manifest it at a clinical level. However, several vulnerability models could help us to identify such individuals. According to them, when similar perturbations at a given task are observed both in clinically stable patients with schizophrenia and their nonschizophrenic first degree relatives, this task could be qualify as an indicator of the vulnerability to schizophrenia. In literature, that seems the case for auditory ERP late components in oddball paradigms. Our study was undertaken to replicate literature data. For that purpose, amplitude and latencies of auditory N100, P200, N200 and P300 wave-forms were assessed among 21 clinically, stable schizophrenics, 21 of their biological full siblings and 21 unrelated control subjects matched with the two others groups for several socio-demographic factors. Comparison were performed by non parametric analyses (Kruskal-Wallis one way ANOVA, and post-hoc Mann-Whitney). Compared to controls, delayed latencies and/or reduced amplitudes were observed for several ERP components--mainly with P300--in the sibling group. ERP values from this group did not statistically differ from those of the group with schizophrenia. In conclusion, results from the sibling group suggest that ERP impairments in auditory oddball paradigms may actually represent indicators of the genetic vulnerability to schizophrenia.

Auditory event-related potentials and clinical scores in unmedicated schizophrenic patients

Event-related potentials (ERPs) have been widely examined in schizophrenic patients. However, although neuroleptic medication could be a potentially confounding variable, studies with unmedicated patients are relatively scarce. The present work was undertaken to determine whether ERP abnormalities persist in stabilized schizophrenic patients after drug withdrawal. In addition, ERP amplitudes and latencies were compared with clinical ratings (the Positive and Negative Syndrome Scale, PANSS) by means of Spearman rank order correlation coefficients. The P300 and N200 responses to rare tones and the P200 and N100 responses to frequent tones were recorded in 20 clinically stabilized drug-free schizophrenic patients and 19 age-matched control subjects during a two-tone discrimination task. Major findings were that the schizophrenic patients had reduced P300, N200 and N100 amplitudes and an increased P300 latency. The P300 amplitude was negatively correlated with age in patients. The P200 latency was negatively correlated with the PANSS positive syndrome score. The ERP abnormalities shown in this study appear to be enduring traits of the disorder as they persist in stabilized patients even after drug withdrawal.

Olfactory identification deficiency and WCST performance in men with schizophrenia

Several studies using the University of Pennsylvania Smell Identification Test (UPSIT), which requires forced choice olfactory identifications, have reported olfactory identification deficits in patients with schizophrenia. This report examines the possible links between olfactory identification (usually attributed to the orbitofrontal cortex) and executive functions (usually attributed to dorsolateral prefrontal cortex) in 24 male patients with schizophrenia and 21 male comparison subjects. Olfactory performance was investigated under two conditions: spontaneous identification and forced choice identification. Executive function was assessed with the Wisconsin Card Sorting Test (WCST). Compared with controls, patients with schizophrenia exhibited a higher average number of cigarettes smoked per day, lower spontaneous identification scores on olfactory performance, and a higher percentage of perseverative errors on the WCST; there was a significant relationship between the two performance measures. Simpson-Angus scores, neuroleptic drug treatment levels, and scores on the Positive and Negative Syndrome Scale were not correlated with either olfactory measure. The lack of correlation between the forced choice olfactory identification score and the WCST score is consistent with findings in previous studies that used the UPSIT. By contrast, use of a spontaneous identification condition to assess olfactory performance did produce a significant association with WCST performance.

[Basic cognitive-perceptive module in schizophrenics]

A specific deficit in gaze discrimination has been hypothesized for schizophrenic patients (Rosse et al., 1994). Gaze discrimination is a basic ability for animals as well as for human beings. It plays an important role in mutual control of social interactions. According to Baron-Cohen (1995), sensitivity to eye gaze relies on a specific cognitive module, the Eye Direction Detector (EDD). The author distinguishes three basic functions of the EDD; first, the EDD is involved in eyes detection; second, the EDD is used in order to establish direction of gaze, and specially to compute whether the eyes one is looking at are directed to the subject or somewhere else; third, the EDD is implied in interpretation of gaze as seeing. Rosse et al. (1994) tested subjective impressions concerning gaze discrimination in a group of schizophrenic patients. Schizophrenics reported the subjective impression of being looked at by the portraits significantly more often than controls. The authors concluded that a specific impairment in gaze detection is present in the patients, and that it may be responsible for the paranoid symptoms often reported in schizophrenia. However, it seems difficult to assert that a response bias in schizophrenics toward perceiving faces as looking at them results from the deficit of an elementary perceptual module responsible for the detection of eye-direction. Rather we suspect such a bias to be the consequence of an impairment of the more complex level of mindreading, responsible for the interpretation of gaze as seeing in terms of mental states. The aim of the present experiment was to test in a more specific way the elementary gaze discrimination system. A series of portraits of models looking at five different directions (-30 degrees, -15 degrees, 0 degree, 15 degrees, 30 degrees), have been presented to 22 schizophrenic patients and 36 normal control subjects. In each trial one portrait was presented. Subjects were asked to determine the direction of its gaze by pressing the "z-key" (left side of the keyboard) if the portrait was looking to the left, and the "/-key" (right side of the keyboard) if the portrait was looking to the right. For each trial, we recorded both the side of the response (left key or right key) and the corresponding reaction time (RT). For the purpose of the analysis, the mean numbers of left responses were computed for each subject. The mean numbers of left responses recorded for each direction of gaze did not significantly differ between patients and controls. That is schizophrenic patients are not impaired in the gaze discrimination task used in the present study. In Rosse's experiment, subjects were required to decide whether the portrait on the screen was looking at them or not. On the contrary, in our task, subjects were simply required to state whether gaze was directed to the right or to the left. No explicit judgment was required as to whom or what gaze was directed. Therefore, we can assume that the present paradigm investigated the functioning of a more basic process than that tested by Rosse et al. Our data are consistent with those reporting that basic cognitive processes are unimpaired in schizophrenia, whereas explicit processes are extensively affected.

Gaze discrimination is unimpaired in schizophrenia

Interpersonal communication is largely dependent on interpretation of facial expression and emotion. Difficulties in face processing, and more specifically in gaze discrimination, have been described in schizophrenic patients. According to Baron-Cohen (Mindblindness. M.I.T. Press, Cambridge, MA, 1995), gaze discrimination relies on the functioning of a specific cognitive module, the Eye Direction Detector (EDD). It has been proposed [Rosse et al. (1994) Gaze discrimination in patients with schizophrenia: preliminary report. American Journal of Psychiatry 151, 919-921] that an impairment in gaze discrimination is present in schizophrenia, and plays a fundamental role in inducing the paranoid symptoms reported by many patients. However, in the previous studies, gaze direction detection and interpretation of gaze have never been completely dissociated. The present experiment attempts to test the schizophrenics' skill in a simple gaze direction detection task. A series of photographic portraits of models looking at different directions have been presented to 22 schizophrenic patients and 36 control subjects. For each portrait subjects were asked to determine whether gaze was directed to the right or to the left by pressing a keyboard key. A forced choice paradigm was used. No differences were reported between schizophrenic patients and control subjects. That is, in the present paradigm, schizophrenic patients did not show any specific impairment in detecting the direction of gaze of the portraits. The results are discussed according to the notion that a dissociation is present in schizophrenia between implicit and explicit processes. The present case illustrates how the more automatic elementary functions, such as the detection of gaze direction, may be spared in schizophrenic patients, whereas explicit cognitive functions are likely more affected.

[Vulnerability to schizophrenia. I: Familial nature of of neuropsychologic indicators]

The existence of a genetic background is now a well admitted notion in schizophrenia, but some individuals at genetic risk for that disease could never manifest it at a clinical level. However, several vulnerability models could help us to identify such individuals. According to them, when similar perturbations at a given test are observed both in clinically stable schizophrenics and their nonschizophrenic first degree relatives, this test could be qualify as an indicator of the vulnerability to schizophrenia. In literature, that seems the case for several neuropsychological tasks, exploring attentional abilities (degraded version of the Continuous Performance Task [DS-CPT], and Span Of Apprehension task [SOA]) and executive functions (Wisconsin Card Sorting Test [WCST]). Our study was undertaken to replicate literature data and to further explore the relationship between these three neuropsychological markers. For that purpose, performances at DS-CPT, SOA and WCST were assessed among 18 clinically stable schizophrenics, 18 of their biological full siblings and 15 unrelated control subjects matched with the two others groups for several socio-demographic factors. Comparisons were performed by non parametric analysis (Kruskal-Wallis one way ANOVA, and Mann-Whitney). Compared to controls, the siblings group performances were significantly impaired on the three tasks, while they did not statistically differ from the schizophrenic ones. No relationship was observed between the markers, except for the "d'" index at DS-CPT and the number of successfully performed categories at the WCST. Results from the sibling group suggested that the observed impaired neuropsychological performances may actually represent indicators of the genetic vulnerability to schizophrenia. Moreover, the generally admitted relationship between WCST poor performances and an impairment of the prefrontal cortex, lead us to hypothesize some role of this brain area in schizophrenia vulnerability.