Ilan Modai
Rappaport Faculty of Medicine
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Featured researches published by Ilan Modai.
European Neuropsychopharmacology | 2004
Michael Ritsner; Rachel Maayan; Anatoly Gibel; Rael D. Strous; Ilan Modai; Abraham Weizman
Dehydroepiandrosterone (DHEA) and its sulfate derivative DHEA-S are neurosteroids, produced in the brain, and neuroactive steroids, produced in the adrenals and affecting the brain. We compared the ratios of serum cortisol/DHEA or DHEA-S in schizophrenia patients with normal subjects, and determined the correlation of these ratios with psychopathology and distress. Early morning plasma concentrations of DHEA, DHEA-S, and cortisol were determined by radioimmunassay in 40 medicated schizophrenia inpatients, and 15 healthy subjects with similar age and sex distribution. Subjects were assessed for psychopathology using the Positive and Negative Syndrome Scale (PANSS) and the Montgomery and Asberg Depression Rating Scale (MADRS), anxiety, anger, emotional and somatic distress levels. Schizophrenia inpatients demonstrated significantly higher levels of state and trait anxiety, anger expression index, emotional and somatic self-reported distress scores. Cortisol/DHEA and cortisol/DHEA-S ratios were significantly higher in schizophrenia patients than in healthy comparison subjects. Both ratios correlated positively with age and duration of illness; cortisol/DHEA-S ratio also showed positive association with age of illness onset. When age, illness duration and age of onset were controlled, cortisol/DHEA-S ratio significantly correlated with severity of depression (MADRS, r=0.33, p=0.048), state and trait anxiety (r=0.43, p=0.008 and r=0.40, p=0.014, respectively), trait anger (r=0.41, p=0.012), angry temperament (r=0.46, p=0.004), anger expression index (r=0.36, p=0.033), and hostility (r=0.42, p=0.010). No significant association was found between these ratios and severity of psychopathology, and type or dosage of antipsychotic agents. Thus, elevated cortisol/DHEA and/or cortisol/DHEA-S ratios in schizophrenia patients are positively associated with higher scores for anxiety and anger, depression and hostility, age and age of onset/duration of illness, but are independent of severity of psychopathology (PANSS) and antipsychotic treatment.
Psychiatry Research-neuroimaging | 2001
Michael Poyurovsky; Sophia Hramenkov; Victoria Isakov; Boris Rauchverger; Ilan Modai; Michael Schneidman; Camil Fuchs; Abraham Weizman
Obsessive-compulsive (OC) symptoms have been observed in a substantial proportion of schizophrenic patients. In this study, we assessed the rate of occurrence of OC symptoms and the interrelationship between OC and schizophrenic symptoms in 68 hospitalized chronic schizophrenic patients. The patients were interviewed with the Structured Clinical Interview for Axis-I DSM-IV Disorders - Patient Edition (SCID-P) and the appropriate rating scales including the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), the Barnes Akathisia Scale, the Abnormal Involuntary Movement Scale, and the Social Behaviour Schedule (SBS). Sixteen patients (23.5%) met the DSM-IV criteria for OCD. A comparison of schizophrenic patients with and without OCD showed that the schizo-obsessive patients were significantly (1.7-fold) more impaired in basic social functioning, as reflected by the SBS score. No significant between-group differences for any of the other clinical variables were found. There was no significant correlation between OC and schizophrenic symptoms within the schizo-obsessive subgroup. The mean Y-BOCS score for the patients with both schizophrenia and OCD was within the typical range (22.8+/-1.7) observed in OCD without psychosis. The findings provide further evidence for the importance of the OC dimension in schizophrenia and may have important implications for the application of effective treatment approaches in this difficult-to-treat subgroup of schizophrenic patients.
Biological Psychiatry | 2000
Avi Peled; Michael Ritsner; Shmuel Hirschmann; Amir B. Geva; Ilan Modai
BACKGROUND The rubber hand illusion is a tactile sensation referred to as an alien limb. The illusion has been explained by a spurious reconciliation of visual and tactile inputs reflecting functional connectivity in the brain and was used to explore alterations of functional connectivity in schizophrenia. METHODS The rubber hand illusion was achieved when two paintbrushes simultaneously stroke the hand of the subject hidden from vision by a screen, as well as an artificial hand placed in view of the subject. The rubber hand illusion was assessed with a questionnaire affirming or denying the occurrence of the illusion. RESULTS Schizophrenic subjects felt the illusion stronger and faster then did normal control subjects. Some rubber hand illusion effects correlated with positive symptoms of schizophrenia but not with negative symptoms. CONCLUSIONS Altered functional integration of environmental inputs could constitute the basis for erroneous interpretations of reality, such as delusions and hallucinations.
European Neuropsychopharmacology | 2002
Michael Ritsner; Alexander M. Ponizovsky; Jean Endicott; Yakov Nechamkin; Boris Rauchverger; Henry Silver; Ilan Modai
This study compared the impact of side-effects of antipsychotic treatment, clinical and psychosocial factors on the subjective quality of life (QOL) of hospitalized patients. We surveyed 161 patients meeting DSM-IV criteria for schizophrenia stabilized on conventional and atypical antipsychotic drugs using standardized measures of adverse events, psychopathology, psychosocial variables, and perceived QOL. We found that patients with adverse events reported less satisfaction with life domains of subjective feelings and general activities than asymptomatic patients. Patients treated with conventional and novel antipsychotic agents had comparable QOL ratings. Multiple regression analysis showed total variance in QOL ratings as follows: psychosocial factors, 20.9%; clinical symptoms and associated distress, 10.1%; adverse effects, 3.2%. Thus, medication side-effects influence subjective quality of life of schizophrenia inpatients significantly less than other clinical and psychosocial factors. Patients subjective response to these events rather than their number is more predictive of QOL.
Schizophrenia Research | 2003
Avi Peled; Assaf Pressman; Amir B. Geva; Ilan Modai
The rubber-hand illusion (RHI), an illusion in which tactile sensations are referred to a synthetic alien limb, is enhanced in schizophrenia patients. Somatosensory evoked responses of the illusion were compared between schizophrenia patients and normal control subjects. Schizophrenia patients had significant alterations in long latency evoked responses during the illusion. These findings support the hypothesis of alterations in associative higher-level neuronal activity in schizophrenia. The findings support previous results pointing to alterations in associative brain regions in schizophrenia.
Journal of the American Academy of Child and Adolescent Psychiatry | 1999
Alexander M. Ponizovsky; Michael Ritsner; Ilan Modai
OBJECTIVE A community survey was conducted to examine suicidal ideation and suicide attempts, behavior problems, psychological distress, social support, and adjustment difficulties in a sample of adolescents. METHOD Four hundred six Russian-born Jewish immigrants to Israel, aged 11 to 18 years, were selected to match the age and sex distribution of the total immigrant adolescent population. Two indigenous samples of Jewish adolescents in Russia (n = 203) and in Israel (n = 104) were matched with immigrants for comparison. Parameters of interest were measured with self-administered questionnaires. RESULTS The 6-month prevalence rate of suicidal ideation in the immigrant sample (10.9%) was significantly higher than that for Russian controls (3.5%) but not for Israeli natives (8.7%). There were few gender differences in suicidal ideation and suicide attempts. Older adolescents reported suicidal ideation 2 times more frequently than their younger counterparts. Suicide ideators scored significantly higher than nonideators on all scales of psychological distress and behavior problems. They rated higher sources of immigration difficulties concerning language, physical health, personality characteristics, and family problems but had less socioeconomic and intercultural problems of migration and lower social support from the family but not from other sources. CONCLUSIONS Results clearly support the migration-convergence hypothesis of suicide risk among adolescents.
Stress Medicine | 2000
Michael Ritsner; Ilan Modai; Alexander M. Ponizovsky
The effects of various stressors and sources of social support on the psychological distress of immigrants were examined. Key variables were measured using the Perceived Immigration Related Stressors Scale, the Multidimensional Scale of Perceived Social Support and the Talbieh Brief Distress Inventory. Data were collected from a community-based sample of 565 adult individuals who recently emigrated from the former Soviet Union to Israel. The most significant stressors reported by immigrants were material-related, followed by culture-, information-, and health-related stressors. Those who perceived that social support was readily available had lower distress ratings than others who believed that social support was not forthcoming. Subjects reported significantly greater social support from family and significant others, than from friends. Social resources (especially support from friends) deterred distress under low stress conditions, but lost the deterring effect as stressors increased. Multiple regression analyses indicated that various combinations of stressors and social support resources explained 50 per cent of the variance in psychological distress under low stress conditions and 27 per cent of the variance as stress intensity increased. In conclusion, the study demonstrates that (1) social-stress factors affect psychological distress and symptoms, (2) social support resources mediate the effects of stressors on psychological distress, and (3) variability in psychological distress is rooted in differential stress-support patterns. Copyright
Biological Psychiatry | 2002
Michael Ritsner; Ilan Modai; Hana Ziv; Sharon Amir; Tami Halperin; Abraham Weizman; Ruth Navon
BACKGROUND In 1999 Cardno et al reported that long CAG repeats in the calcium-activated potassium channel gene hSKCa3/KCNN3 are associated with higher negative symptom dimension scores in schizophrenia patients. There has been no attempt to replicate the results. In this study, we investigated whether a symptom polymorphism of schizophrenia is associated with both the CAG repeat numbers and the difference in allele sizes. METHODS We tested the association of CAG repeats with symptom models of schizophrenia in 117 unrelated Jewish patients. A multivariate analysis (MANOVA) of two models of schizophrenia with the repeat distribution and the difference in allele sizes was performed. RESULTS We found a significant positive association of the number of CAG repeats with negative syndrome, anergia, activation, and paranoid symptoms. In addition, nonparanoid schizophrenia patients who had differences in allele sizes were characterized by earlier onset of illness. CONCLUSIONS The study supports the hypothesis that the combined effect of long CAG repeats and the differences in allele sizes contribute to symptom expression of schizophrenia, particularly on the anergia-activation-paranoid axis.
Journal of Psychiatric Research | 2003
Michael Ritsner; Ilan Modai; Anatoly Gibel; Svetlana Leschiner; Henry Silver; German Tsinovoy; Abraham Weizman; Moshe Gavish
Peripheral-type benzodiazepine receptors (PBR) have been shown to be sensitive to stressful conditions. This study aimed to explore a possible association of platelets PBR binding with aggressive behavior and homicidal history in schizophrenia patients. The authors compared [(3)H] PK 11195 binding to platelet membrane among 11 currently aggressive schizophrenia patients, 15 schizophrenia patients with homicidal history, 14 nonaggressive schizophrenia patients, and 15 healthy volunteers. Subjects were assessed for aggressive behavior, psychopathology, anxiety, anger, and emotional distress using standardized instruments. We found that currently aggressive patients had significantly lower (-30%) platelet PBR density (B(max)), and scored significantly higher on hostility, anxiety, state anger, and emotional distress compared to homicidal and nonaggressive schizophrenia patients and healthy controls. Predominance of positive or negative symptoms, homicidal or suicidal attempt history, emotional distress levels, and conventional or atypical antipsychotic therapy is not associated with the expression of platelet PBR binding sites. Significant negative correlations emerged between PBR density and scores for aggressive behavior, hostility and anxiety. Thus, decreased platelet PBR density in aggressive schizophrenia patients is associated with higher scores for overt aggression, hostility and anxiety, but independent of illness subtype, homicidal and suicidal attempt history, distress level and type of antipsychotic treatment.
Schizophrenia Research | 2001
Alexander M. Ponizovsky; Ilan Modai; Y. Nechamkin; Gregory Barshtein; Michael Ritsner; Saul Yedgar; S. Lecht; L.D. Bergelson
The phospholipid composition of red blood cells (RBC) from 32 haloperidol-treated schizophrenic patients, classified according to the positive and negative syndrome scale (PANSS) as showing either predominantly positive or predominantly negative symptoms, was determined and compared with that of normal controls. While the levels of phosphatidylcholine and phosphatidylserine were similar in all three groups, sphingomyelin (SM) and phosphatidylethanolamine (PE) were, respectively, increased and decreased in RBCs of schizophrenic patients. In both patient groups, the SM/PE ratios correlated directly with the PANSS negative symptom scale scores and inversely with the positive symptom scale scores. However, the inverse changes in the contents of SM and PE were much more expressed in the negative group. It is suggested that a main source of that difference is a higher activity of the polyunsaturated acid-selective phospholipase A(2) in the negative syndrome patients than in the positive syndrome and control groups.