Biomedical subjects

Gabriela Knoll

Publications and source records attributed to Gabriela Knoll.

3 recordsLinked to original sources

PubMed2005

COMT Val158Met polymorphism in schizophrenia with obsessive-compulsive disorder: a case-control study.

This is the first study of a possible molecular genetic basis for schizophrenia with obsessive-compulsive disorder (OCD). We performed a case-control association study of the catechol-O-methyltransferase (COMT) Val158Met polymorphism in schizophrenia-OCD patients, OCD and healthy controls. One hundred and thirteen schizophrenia-OCD patients, 79 OCD patients and 171 control subjects were genotyped for the Val(158)Met polymorphism in the COMT gene. There was no significant difference in allele and genotype distribution of the COMT gene between schizophrenia-OCD patients and healthy controls. The low-activity Met allele and Met/Met genotype were more frequent in OCD men than in schizophrenia-OCD and control individuals. This difference, however, was not statistically significant following correction for multiple comparisons. These results do not support the hypothesis that the COMT Val158Met gene polymorphism is associated with liability to schizophrenia-OCD.

Case-Control Studies↗

PubMed2005

A double-blind, cross-over comparison of the effects of amantadine or placebo on visuomotor and cognitive function in medicated schizophrenia patients.

The present study aimed to test the hypothesis that dopamine agonists may enhance cognitive function. The effect of amantadine on neuropsychological function in medicated schizophrenia patients was investigated. The study comprised an add-on, double-blind, placebo-controlled, cross-over 6-week trial. Participants comprised 29 inpatients at Sha'ar Menashe Mental Health Center who were diagnosed with chronic schizophrenia or schizoaffective disorder. Amantadine 200 mg/day or identical placebo was added to ongoing antipsychotic treatment for 3 weeks. Study medications were then switched for an additional 3 weeks. Assessments were performed at baseline, and weeks 3 and 6, including cognitive and visuomotor assessments. Clinical ratings included positive, negative and depressive symptoms and extrapyramidal side-effects. Blood prolactin levels were assayed. A mixed model was used to examine differences in the data at the three assessment points. Amantadine was associated with improved visuomotor coordination compared to placebo. No significant changes in cognitive functions were noted. Clinical symptoms, extrapyramidal side-effects and blood prolactin levels were not altered. Amantadine improved visuomotor coordination independently of extrapyramidal side-effects but not cognitive function. Because prolactin concentrations were unchanged, the mechanism is more likely to involve glutaminergic NMDA than dopaminergic mechanisms. Further studies of amantadine with different doses and treatment duration, as well as more glutamate selective agents such as memantine, are indicated.

Adult↗

PubMed2004

Brief emotion training improves recognition of facial emotions in chronic schizophrenia. A pilot study.

Impaired emotional communication may be an important contributing factor to poor social function in schizophrenia. This pilot study examined the effect of emotion training exercises on the perception of facial emotional expression. Twenty male chronic schizophrenia patients underwent three training sessions using a computerized Emotion Training program, developed for teaching autistic children, which was adapted to the clinical setting. Patients were assessed before and after training with validated tests of identification of facial emotions (PEAT, ER40), differentiation of facial emotions (EmDiff) and working memory. In comparison to baseline, patients performed significantly better on the PEAT and ER40 tests after training. No change was observed in EmDiff or in cognitive test performance. Brief Emotion Training can improve recognition of facial emotional expressions in chronic schizophrenia patients. This may be due to increased patient awareness of emotional aspects of stimuli and/or improvement in specific emotional perceptual skills. Further studies of Emotion Training as a potential treatment modality are warranted.

Adult↗