Biomedical subjects

A Botsis

Publications and source records attributed to A Botsis.

3 recordsLinked to original sources

PubMed2000

Five-factor model of schizophrenic psychopathology: how valid is it?

Aim of the study was to examine the consistency of the five-factor model of schizophrenic symptoms, assess its validity and evaluate its dimensional factor structure using confirmatory factor (CFA) analysis. A sample of 258 randomly assigned DSM-III R patients with schizophrenic disorders were studied by means of the structured clinical interview for the Greek validated Positive and Negative Syndrome Scale (PANSS) and were rated on its 30 items. Patients' scores were subjected to principal component analysis (PCA) with varimax rotation. Internal consistency for each of the components was determined by the use of Cronbach's alpha. External validity of the model derived was investigated by searching for possible relationships between the components and sociodemographic characteristics with the aid of canonical correlation analysis. Confirmatory factor analysis (CFA) was also performed. Using the scree plot criterion PCA revealed a five-factor model. These factors were interpreted as representing--in a decreasing order of relative importance--the following dimensions of schizophrenic psychopathology: negative, excitement, depression, positive and cognitive impairment. The model was comparable with six previous factor analytic studies. Internal consistency was quite satisfactory whereas external validity was found to be not so powerful. CFA did not show that the proposed model yields an adequate factor structure.

Adult↗

PubMed1992

Biogenic amine metabolites in plasma of drug-naive schizophrenic patients: associations with symptomatology.

The main metabolites of dopamine, noradrenaline, and serotonin, homovanillic acid, methoxyhydroxyphenylglycol (MHPG), and 5-hydroxyindoleacetic acid (5-HIAA), were estimated in plasma of 20 drug-naive young male schizophrenic patients and 21 healthy controls. Although there were no significant differences between the two groups, multiple regression analysis revealed strong associations of the patients' 5-HIAA and MHPG plasma levels to their scores in the Brief Psychiatric Rating Scale items. 5-HIAA levels were mainly related positively to hostility and negatively to somatic concern, and MHPG positively to disorientation and negatively to emotional withdrawal and uncooperativeness. The results suggest that levels of the neurotransmitter metabolites may be related to certain psychological dysfunctions of the patients rather than to disease entities.

Adult↗

PubMed1988

An experimental antidepressant increases REM sleep.

1. An experimental antidepressant was studied through sleep laboratory recordings, psychoendocrinological tests and clinical measurements in terms of its efficacy, side effects and effects on sleep. 2. The design included a four-week drug administration period, preceeded and followed by a one week placebo period. 3. In the presence of antidepressant efficacy, the drug did not disturb sleep induction and maintainance. 4. The only effect on sleep stages was an increase of REM sleep during the short-term drug administration period which is contrary to the REM supressant effect of most antidepressants. 5. This finding suggests that REM supression and antidepressant efficacy are not necessarily related. 6. Further, given that the only known action of the drug is its inhibitory effect on GABAergic transmission, one can speculate that GABA mechanisms may be involved in REM sleep modulation.

Antidepressive Agents↗