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Dive into the research topics where Abraham Weizman is active.

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Featured researches published by Abraham Weizman.


Biological Psychiatry | 2004

Rapid antidepressive-like activity of specific glycogen synthase kinase-3 inhibitor and its effect on β-catenin in mouse hippocampus

Oksana Kaidanovich-Beilin; Anat Milman; Abraham Weizman; Chaim G. Pick; Hagit Eldar-Finkelman

BACKGROUND Inhibition of glycogen synthase kinase-3 (GSK-3) is thought to be a key feature in the therapeutic mechanism of several mood stabilizers; however, the role of GSK-3 in depressive behavior has not been determined. In these studies, we evaluated the antidepressive effect of L803-mts, a novel GSK-3 peptide inhibitor, in an animal model of depression, the mouse forced swimming test (FST). METHODS Animals were intracerebroventricularly injected with L803-mts or with respective control peptide (cp) 1 hour, 3 hours, or 12 hours before their subjection to FST. RESULTS Animals administered L803-mts showed reduced duration of immobility at all three time points tested, as compared with cp-treated animals. Expression levels of beta-catenin, the endogenous substrate of GSK-3, increased in the hippocampus of L803-mts-treated animals by 20%-50%, as compared with cp-treated animals. CONCLUSIONS Our studies show, for the first time, that in-vivo inhibition of GSK-3 produces antidepressive-like behavior and suggest the potential of GSK-3 inhibitors as antidepressants.


Journal of the American Academy of Child and Adolescent Psychiatry | 2009

Psychiatric Disorders and Intellectual Functioning Throughout Development in Velocardiofacial (22q11.2 Deletion) Syndrome

Tamar Green; Doron Gothelf; Bronwyn Glaser; Martin Debbané; Amos Frisch; Moshe Kotler; Abraham Weizman; Stephan Eliez

OBJECTIVE Velocardiofacial syndrome (VCFS) is associated with cognitive deficits and high rates of schizophrenia and other neuropsychiatric disorders. We report the data from two large cohorts of individuals with VCFS from Israel and Western Europe to characterize the neuropsychiatric phenotype from childhood to adulthood in a large sample. METHOD Individuals with VCFS (n = 172) aged 5 to 54 years were evaluated with structured clinical interviews for psychiatric disorders and age-appropriate versions of the Wechsler intelligence tests. RESULTS The frequency of psychiatric disorders was high and remarkably similar between samples. Psychotic disorders and depression were uncommon during childhood but increased in rates during adulthood (depressive disorders: 40.7% in young adults [aged 18-24 years]; psychotic disorders: 32.1% in adults [age >24 years]). Cognitive scores were inversely associated with age in subjects with VCFS, including patients without psychosis. Specifically, Verbal IQ (VIQ) scores negatively correlated with age, and the subjects with VCFS and psychotic disorders had significantly lower VIQ scores than nonpsychotic VCFS subjects. CONCLUSIONS Neuropsychiatric deficits in individuals with VCFS seem to follow a developmental pattern. The VIQ scores are negatively associated with age and rates of mood, and psychotic disorders increase dramatically during young adulthood. The data presented here support careful monitoring of psychiatric symptoms during adolescence and young adulthood in VCFS. Prospective longitudinal studies are needed to examine the nature of age-related cognitive changes and their association with psychiatric morbidity in VCFS.


Biological Psychiatry | 1997

Elevated levels of serum interleukin-1β in combat-related posttraumatic stress disorder

Baruch Spivak; Batya Shohat; Roberto Mester; Shlomit Avraham; Irit Gil-Ad; Avraham Bleich; Avi Valevski; Abraham Weizman

Levels of serum interleukin-1 beta (IL-1 beta) and soluble interleukin-2 receptor (sIL-2R) were assessed in 19 male patients with combat-related posttraumatic stress disorder (PTSD) in comparison to 19 age- and sex-matched healthy volunteers. Serum IL-1 beta levels (but not sIL-2R) were significantly higher (p < .001) in the PTSD patients than in the controls. IL-1 beta levels did not correlate with cortisol levels, severity of PTSD, anxiety, depressive symptoms, or alexithymia score; however, they did correlate significantly (r = .54, p < .005) with the duration of PTSD symptoms. It is possible that desensitization of the hypothalamic-pituitary-adrenal axis in chronic PTSD patients counteracts the stimulatory effect of IL-1 beta on cortisol secretion.


Life Sciences | 1987

Serotonin 5-HT2 receptor binding on blood platelets - a peripheral marker for depression?

Anat Biegon; Abraham Weizman; L. Karp; A. Ram; S. Tiano; M. Wolff

Several methods of platelet membrane preparation and binding conditions were screened in order to optimize the labeling of serotonergic 5-HT2 receptors on previously frozen human platelet membranes with tritiated ketanserin. Under optimal conditions, 5-HT2 receptors in normal subjects (5 males, 7 females, age range 21 to 71) have a Kd of 1.5 +/- 0.2 nM and a Bmax of 33.9 +/- 5.3 fmole/mg protein. In a group of patients with major depressive disorder exactly matched for age and sex with the normal control group, we find a significant increase in receptor density, to 66.8 +/- 11.4 fmole/mg, with no significant change in the affinity (2.3 +/- 0.5 nM). Four weeks of treatment with antidepressant drugs result in a significant decrease of Bmax, down to control levels (29.4 +/- 3.9). Thus, ketanserin can be used to monitor changes in platelet serotonin 5-HT2 receptors which may be a relevant marker for the state of depression.


American Journal of Medical Genetics | 2004

Obsessive-compulsive disorder in patients with velocardiofacial (22q11 deletion) syndrome

Doron Gothelf; Gadi Presburger; Ada H. Zohar; Merav Burg; Ariela Nahmani; Moshe Frydman; Mordechai Shohat; Dov Inbar; Ayala Aviram-Goldring; Josepha Yeshaya; Tamar Steinberg; Yehuda Finkelstein; Amos Frisch; Abraham Weizman; Alan Apter

The study of neurogenetic microdeletion syndromes provides an insight into the developmental psychopathology of psychiatric disorders. The aim of the study was to evaluate the prevalence of psychiatric disorders, especially obsessive‐compulsive disorder (OCD), in patients with velocardiofacial syndrome (VCFS), a 22q11 microdeletion syndrome. Forty‐three subjects with VCFS of mean age 18.3 ± 10.6 years were comprehensively assessed using semi‐structured psychiatric interview and the Yale–Brown obsessive compulsive scale (Y‐BOCS). Best estimate diagnoses were made on the basis of information gathered from subjects, parents, teachers, and social workers. Fourteen VCFS subjects (32.6%) met the DSM‐IV criteria for OCD. OCD had an early age of onset and generally responded to fluoxetine treatment. It was not related to mental retardation. The most common obsessive‐compulsive symptoms were contamination, aggression, somatic worries, hoarding, repetitive questions, and cleaning. Sixteen of the 43 patients (37.2%) had attention‐deficit/hyperactivity disorder (ADHD), and 7 (16.2%) had psychotic disorder. The results of our study suggest that there is a strong association between VCFS and early‐onset OCD. This finding may be significant in the understanding of the underlying genetic basis of OCD.


European Neuropsychopharmacology | 2004

Elevation of the cortisol/dehydroepiandrosterone ratio in schizophrenia patients.

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

Obsessive-compulsive disorder in hospitalized patients with chronic schizophrenia.

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.


Journal of Molecular Neuroscience | 2005

Differential Induction of Apoptosis by Antidepressants in Glioma and Neuroblastoma Cell Lines

Yechiel Levkovitz; Irit Gil-Ad; Ella Zeldich; Michal Dayag; Abraham Weizman

Several antidepressants, mainly selective serotonin-reuptake inhibitors (SSRIs) and some tricyclic antidepressants (TCAs), have been shown to possess potent apoptotic activity in different cell lines. Our aim was to screen and select those agents with significant activity and elucidate the molecular pathway underlying this process in rat glioma and human neuroblastoma cell lines. We studied the effect of different antidepressants on apoptotic markers, including: cell viability, DNA fragmentation, cytochrome c (Cyt c) release from mitochondria, and caspase-3-like activity. In addition, the involvement of MAPK genes, c-Jun, and ERK was determined. Paroxetine and fluoxetine, SSRIs, clomipramine, a TCA, but not imipramine or mianserin (an atypical antidepressant), caused apoptosis in both cell lines, as assessed by flow cytometry of propidium iodide-stained C6 cells and typical fluorescence microscopy in glioma cells. These apoptotic changes were preceded by rapid increase in p-c-Jun levels, Cyt c release from mitochondria, and increased caspase-3-like activity. Assessment of paroxetine cytotoxicity in primary mouse brain and neuronal cultures showed significantly lower sensitivity to the drug’s proapoptotic activity. These results strongly suggest that selected antidepressants induce apoptosis in neuronal and glial cell lines. Activation of p-c-Jun and subsequent increased Cyt c mitochondrial release participate in the apoptotic mechanism of the antidepressant. The high sensitivity to these drugs of the cancer cell, compared with primary brain tissue, suggests the potential use of these agents in the treatment of brain-derived tumors.


Advances in Psychosomatic Medicine | 2008

The Impact of Mental Illness on Sexual Dysfunction

Zvi Zemishlany; Abraham Weizman

Sexual dysfunction is prevalent among psychiatric patients and may be related to both the psychopathology and the pharmacotherapy. The negative symptoms of schizophrenia limit the capability for interpersonal and sexual relationships. The first-generation antipsychotics cause further deterioration in erectile and orgasmic function. Due to their weak antagonistic activity at D2 receptors, second-generation antipsychotics are associated with fewer sexual side effects, and thus may provide an option for schizophrenia patients with sexual dysfunction. Depression and anxiety are a cause for sexual dysfunction that may be aggravated by antidepressants, especially selective serotonin reuptake inhibitors (SSRIs). SSRI-induced sexual dysfunction may be overcome by lowering doses, switching to an antidepressant with low propensity to cause sexual dysfunction (bupropion, mirtazapine, nefazodone, reboxetine), addition of 5HT2 antagonists (mirtazapine, mianserin) or coadministration of 5-phosphodiesterase inhibitors. Eating disorders and personality disorders, mainly borderline personality disorder, are also associated with sexual dysfunction. Sexual dysfunction in these cases stems from impaired interpersonal relationships and may respond to adequate psychosexual therapy. It is mandatory to identify the specific sexual dysfunction and to treat the patients according to his/her individual psychopathology, current pharmacotherapy and interpersonal relationships.


Schizophrenia Research | 2005

Cancer in schizophrenia: is the risk higher or lower?

Alexander Grinshpoon; Micha Barchana; Alexander M. Ponizovsky; Irena Lipshitz; Daniella Nahon; Orna Tal; Abraham Weizman; Itzhak Levav

Studies exploring the relationship between schizophrenia and cancer have shown conflicting results. Our study explores this association in three Jewish-Israeli population groups defined by their continent/place of birth (Israel, Europe-America, and Africa-Asia). The identification of the patients was made through the linkage of the nationwide psychiatric and cancer registries. The incidence of cancer in patients diagnosed with schizophrenia was compared with the incidence in the general population. The results showed that the cancer standardized incidence ratios (SIRs) for all sites were significantly lower among men and women with schizophrenia, 0.86 [95% confidence interval (CI) 0.80-0.93] and 0.91 (95% CI 0.85-0.97), respectively. This reduced overall risk was clearest for those born in Europe-America, both men (SIR 0.85, 95% CI 0.74-0.97) and women (SIR 0.86, 95% CI 0.77-0.94). Among women diagnosed with schizophrenia, the SIR was statistically higher for cancer in the breast among those born in Asia-Africa (1.37, 95% CI 1.12-1.63) and in the corpus uteri among the Israel-born (2.75, 95% CI 1.69-3.81) than among their counterparts in the general population. Lung cancer was significantly higher in men born in Asia-Africa diagnosed with schizophrenia than in the respective comparison population group (1.58, 95% CI 1.13-2.2). Our findings, and those of the literature, justify conducting a multinational study that includes identification of cancer-related risk factors among patients with schizophrenia and their families, and information on the use of psychotropic medications. This effort may clarify an epidemiological puzzle that remains outstanding.

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Michael Poyurovsky

Technion – Israel Institute of Technology

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