Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several researchers have investigated the relationships between computed tomographic and electroencephalographic abnormalities in schizophrenics. In this present investigation, 28 medicated schizophrenic patients fulfilling the DSM-III-R criteria for schizophrenia and 21 normal volunteers were studied by means of MRI and EEG examinations. All subjects had given informed consent to the investigation. The schizophrenic patients (14 males, 14 females) were aged from 21 to 39 with a mean age of 30.2. The control group consisted of age- and sex-matched healthy volunteers (11 males, 11 females) with no history of neurological disease or head trauma. All the subjects were right-handed as determined by the Edinburgh Inventory. Schizophrenic and control subjects underwent MRI scan and EEG within two weeks. Three trained psychiatrists evaluated patients for BPRS and SANS and the score each item was the median of the three raters. MRI scans were performed by a Asahi Super 200 scanner operating at a 2.0 Tesla magnetic field. A midsagittal scan (8 mm thickness, Spin Echo 500/26) was taken. Subsequently, 15 axial and coronal slices of 5 mm interslice with 2 mm gap were obtained using an Inversion-Recovery sequence (TR: 3000, TI: 800, TE: 14). For measurement purposes, the three MRI scans (Fig-1) were recorded on transparent film, and the boundaries of the cerebral structures were taken traced from the film onto a digitizing tablet. The EEGs were recorded from 16 scalp electrodes of the standard 10/20 system referenced to linked ear electrodes at rest and digitized by a topographic system (Neuromap system MCE-5100, QCE-510B, Nihon Kohden). To calculate EEG power, the frequency spectrum was divided into six EEG frequency bands by 0.25 Hz bands. Each power value was taken from the average percentage of total power and then log-transformed. Schizophrenic patients showed a significantly larger VBR on the axial and coronal planes than control subjects. The areas of the bilateral anterior horns, left body, left posterior horn of the lateral ventricle and the third ventricle were significantly larger in schizophrenic patients than in control subjects. The area of middle half of the corpus callosum in schizophrenic patients was smaller than in control subjects. Schizophrenic patients showed more delta and theta activities in the centro-parieto-occipital regions than control subjects. Schizophrenic patients also showed more beta 1 and beta 2 activities in front-central regions than control subjects. On the other hand, schizophrenic patients showed a markedly decrease in alpha 2 activity in all regions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Studies of the correlations between morphological brain changes on MRI and computerized EEG changes in schizophrenics]. 152 74

An experimental method to test the hypothesis that antipsychotic (neuroleptic) agents influence gene expression in the mouse brain has been developed using the cis and trans stereoisomers of flupenthixol. The cis form of the drug is known to be clinically effective against some of the psychotic symptoms of schizophrenia as opposed to the trans isomer which is relatively inactive. A 2- to 3-fold increase in the abundance of dopamine 2 receptor mRNA was observed in the cis treated mice after a period of ten weeks. No change was observed in the expression of the dopamine D2 receptor gene upon treatment with the trans isomer. No change in the amount of 5-HT1A, 5-HT1C, alpha 1 adrenergic, beta 1 and beta 2 adrenergic neuroreceptor mRNA was found in the mice treated with active drug. The results show a long-term adaptation to D2 antagonism at the level of gene expression which occurs over a similar time scale to that of the clinical response to neuroleptic treatment of schizophrenia.
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PMID:Stereospecific effect of flupenthixol on neuroreceptor gene expression. 164 66

We undertook a study of electroencephalograms (EEGs) in 30 right-handed, untreated patients (27.3 +/- 10.0 years; hebephrenic, 16; paranoid, 12; residual, 2) who fulfilled ICD-9 criteria for schizophrenia and compared them with sex- and age-matched controls by using the percentage of power in six EEG frequency bands calculated as a fraction of total power. T-statistic significance probability mapping (t-SPM) showed that, compared with normal controls, schizophrenics had more slow activity (delta, theta, and alpha 1) in the parieto-occipital regions, and more fast activity (beta 1) in the occipital regions. In contrast, alpha 2 activity decreased strikingly in the occipital regions and this decreased activity extended over much of the head. These findings were thought to indicate both cerebral hypofunction and excitability in acute untreated schizophrenia.
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PMID:Computerized EEG in schizophrenic patients. 222 18

Alterations in gamma-aminobutyric acid (GABA) neurotransmission have been indirectly implicated in the pathogenesis of schizophrenia. Using nine multiplex pedigrees, we tested for linkage between schizophrenia and simple sequence repeat polymorphisms for the GABAA receptor alpha 1, alpha 2, alpha 4, alpha 5, alpha 6, beta 1 and beta 3 subunit genes. Evidence of linkage was not found when assuming either autosomal dominant or autosomal recessive inheritance. The non-parametric sib pair test also did not reveal significant evidence of deviation from expected segregation ratios.
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PMID:Schizophrenia and GABAA receptor subunit genes. 758 77

Since results of conventional FFT-power-analysis are reference-dependent, only unambiguous neurophysiological data should be used for a functional physiological interpretation of EEG-data. FFT-approximation with successive center-of-gravity-dipole calculation gives unambiguous EEG-data with regard to recording reference. In the present investigation 22 medicated schizophrenic patients were compared with 22 healthy age- and sex-matched controls with regard to spontaneous resting EEG. More anterior and superficial equivalent-dipoles were found in the beta-bands for schizophrenic patients compared to healthy control subjects. There was a tendency of increased beta-activity in schizophrenic subjects. With more severe schizophrenic symptoms (higher BPRS-score), the more anterior was the equivalent-dipole localization in the beta 1-band, and the deeper in the theta-band. The different locations of the beta-band dipoles in schizophrenic patients suggest that different neuronal populations generate beta-activity in schizophrenia compared to healthy controls. FFT-approximation allows a substantial and meaningful data reduction in multichannel recordings and will hopefully help in understanding pathological brain functions in schizophrenia.
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PMID:Electrical brain activity in schizophrenia described by equivalent dipoles of FFT-data. 771 Sep 95

In this study we performed quantitative EEG analyses in 12 drug-naive patients who fulfilled DSM-IIIR criteria for schizophrenia and in a group of 12 healthy subjects. The schizophrenic patients were found to have slower activity (delta and theta) than the controls. These differences were most marked in the frontal region for delta band and in the occipital region for theta band. The schizophrenic patients also had more beta 1 activity, particularly in the occipital leads. Conversely, they had less alpha 2 activity over all regions examined. Our findings indicate cerebral dysfunction in schizophrenia and are in line with the hypothesis of hypofrontality in this disorder.
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PMID:[Quantitative analysis of EEG background activity in drug-naive schizophrenic patients]. 806 45

As alterations in GABAergic neurotransmission have been indirectly implicated in the pathogenetics of schizophrenia, GABAA receptor subunit genes are plausible candidate genes for the illness. We undertook a search for sequence variations in the coding region of beta 1 subunit gene by designing intron-based primers to amplify its 9 exons. Using single strand conformation polymorphism (SSCP) analysis, we found an exon 9 variant present in 3 of 86 unrelated schizophrenic cases derived from families having at least 2 first-degree relatives with schizophrenia. Direct sequencing of the SSCP variant revealed a C-->G nucleotide transversion at codon 396 predicting a histidine to glutamine substitution in the beta 1 peptide. The predicted amino acid substitution occurs at a highly conserved site, 9 residues from a cAMP-dependent serine phosphorylation consensus sequence. All known GABAA beta 1 subunit genes including human, bovine, and rat, code for histidine at position 396. Although the variant cosegregated with disease in a family with 2 affected sibs, it was only transmitted to 2 of 3 affected sibs in a multiplex family. The variant was not found in an additional sample comprising 155 unrelated schizophrenics and the sequence variant was present at a low frequency (approximately 1.1%) in control groups. Although these results indicate that the sequence variant is likely to be a natural polymorphism, it is possible that the variant may be a predisposing allele in rare instances. It is also possible that the variant may change the function or regulation of the GABAA receptor complex and it may be of pharmacogenetic relevance.
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PMID:Search for mutations in the beta 1 GABAA receptor subunit gene in patients with schizophrenia. 817 35

Computerized electroencephalogram (CEEG) data were obtained from 30 patients with the disorganized type and 20 patients with the paranoid type of acute untreated schizophrenia and compared with data from age- and sex-matched controls. All patients with acute untreated schizophrenia exhibited more pronounced delta, theta, alpha 1 and beta 1 activity and less prominent alpha 2 activity than the control subjects. These findings support previous studies, and indicate the coexistence of cerebral hypofunction and excitability in acute schizophrenic patients. Compared with the controls, patients with disorganized type schizophrenia had significant increases in theta and beta 1 and decreases in alpha 2 activities; but a significant increase in delta and alpha 1 activities in the posterior regions and beta 2 activity in the frontal regions of the brain. Patients with paranoid type schizophrenia showed significantly increased delta activity in the posterior regions, increased alpha 1 activity in the anterior regions and decreased alpha 2 activity in both these regions. In the paranoid type, however, there was no significant finding for the theta, beta 1 and beta 2 activities. Disorganized type schizophrenics exhibited more increased theta and decreased alpha 2 activity than patients with paranoid type schizophrenia. The CEEG differences between the disorganized and the paranoid types appear to reflect different clinical entities and may help to differentiate both schizophrenias.
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PMID:Computerized electroencephalogram in untreated schizophrenics: a comparison between disorganized and paranoid types. 878 78

Transforming growth factor beta s (TGF beta s) are potent immunosuppressive molecules released in the brain after injury. We hypothesized that TGF beta levels in cerebrospinal fluid (CSF) of schizophrenic patients would be altered because TGF beta can influence neural cell adhesion molecule (N-CAM) expression in vitro. The levels of TGF beta 1 and beta 2 in CSF of patients with schizophrenia and normal controls measured by ELISA showed no differences. There was evidence that the stability of TGF beta in CSF may be altered in schizophrenia. For a limited sample, TGF beta 1 and N-CAM concentrations were significantly correlated in normal patients (r = 0.98) but not in schizophrenics. The results do not support an active neurodegeneration or anti-inflammatory response in the central nervous system, which is reflected in the CSF of chronic schizophrenics.
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PMID:Transforming growth factors beta 1 and beta 2 in the cerebrospinal fluid of chronic schizophrenic patients. 898 92

Electrophysiological studies have demonstrated gamma and beta frequency oscillations in response to auditory stimuli. The purpose of this study was to test whether auditory hallucinations (AH) in schizophrenia patients reflect abnormalities in gamma and beta frequency oscillations and to investigate source generators of these abnormalities. This theory was tested using quantitative electroencephalography (qEEG) and low-resolution electromagnetic tomography (LORETA) source imaging. Twenty-five schizophrenia patients with treatment refractory AH, lasting for at least 2 years, and 23 schizophrenia patients with non-AH (N-AH) in the past 2 years were recruited for the study. Spectral analysis of the qEEG and source imaging of frequency bands of artifact-free 30 s epochs were examined during rest. AH patients showed significantly increased beta 1 and beta 2 frequency amplitude compared with N-AH patients. Gamma and beta (2 and 3) frequencies were significantly correlated in AH but not in N-AH patients. Source imaging revealed significantly increased beta (1 and 2) activity in the left inferior parietal lobule and the left medial frontal gyrus in AH versus N-AH patients. These results imply that AH is reflecting increased beta frequency oscillations with neural generators localized in speech-related areas.
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PMID:Quantitative EEG and low resolution electromagnetic tomography (LORETA) imaging of patients with persistent auditory hallucinations. 1652 99


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