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P Falkai

Publications and source records attributed to P Falkai.

At least 91 records · Page 5Linked to original sources
PubMed1997

Cingulate cortex synaptic terminal proteins and neural cell adhesion molecule in schizophrenia.

The neuronal organization and patterns of afferent innervation are abnormal in the cingulate cortex in schizophrenia, and associated changes in synaptic terminals could be present. A panel of monoclonal antibodies was defined with biochemical and fusion protein studies as detecting syntaxin (antibody SP6), synaptophysin (antibody SP4) and synaptosomal-associated protein-25 (antibody SP12). These antibodies and a polyclonal antibody reactive with neural cell adhesion molecule were used to investigate the cingulate cortex in schizophrenia. Immunocytochemistry indicated that syntaxin immunoreactivity had a considerably wider distribution than synaptophysin. Overall, multivariate analysis indicated increased synaptic terminal protein immunoreactivity in schizophrenia compared to controls (P=0.004). Controlled for age and post mortem interval, syntaxin immunoreactivity was significantly elevated in schizophrenia (P=0.004), and neural cell adhesion molecule immunoreactivity was also elevated (P=0.05). The neural cell adhesion molecule to synaptophysin ratio was increased (P=0.005), possibly indicating the presence of less mature synapses in schizophrenia. Elevated syntaxin immunoreactivity is consistent with increased glutamatergic afferents to the cingulate cortex in schizophrenia, and combined with the neural cell adhesion molecule to synaptophysin ratio results suggests that synaptic function in this region in schizophrenia may be abnormal.

Antigens↗
PubMed1997

A comprehensive method of assessing routine CT scans in schizophrenia.

Morphological brain abnormalities are common in schizophrenia, although the aetiological and clinical significance of these findings is largely unknown. Substantial between-subject variability suggests that large samples are needed to study the full implications of brain pathomorphology. Computerized tomography (CT) is frequently used routinely in schizophrenia, and large numbers of scans are available for study. This article describes the development and statistical properties of a rapid and simple method of assessing CT scans. The CT Rating Scale for Schizophrenia (CTRSS) is minimally affected by variability in scanning procedures, is reliable, and accurately estimates area and volumetric measures of brain spaces. By promoting the comprehensive assessment of large numbers of routinely obtained scans, the CTRSS would allow the investigation of variables that may systematically affect results (e.g. gender and age) and variables with low prevalence. The CTRSS provides a useful adjunct to technologically more sophisticated methods of assessment such as magnetic resonance imaging (MRI).

Adult↗
PubMed1996

A case study of temporal lobe development in familial schizophrenia.

Case studies of patients with familial schizophrenia may help to define the pathophysiology of this illness and indicate potential candidate genes for genetic linkage studies. In this regard, the clinical, radiological and pathological assessments of a 39-year-old affected man from a pedigree with familial schizophrenia are presented. Brain imaging with CT indicated moderate cortical atrophy, particularly of the temporal lobes. Neuropathological examination revealed granular ependymitis, indicating possible past ventricular pathology. Granular ependymitis was reported to occur in genetic developmental disorders with neuronal migration abnormalities. In the present case, heterotopic clusters of neurons were visualized in the entorhinal cortex, suggesting that temporal lobe development was not entirely normal. This case study suggests that genetic factors could be investigated further as one possible aetiology of certain neurodevelopmental abnormalities observed in schizophrenia.

Adult↗
PubMed1996

Differential diagnosis in acute psychotic episode.

Clinically unsuspected, usually neurodevelopmental, brain lesions of aetiological relevance occur in 6-10% of schizophrenic patients. About 3% of secondary schizophrenia arises in the presence of systemic physical illness, Psychopathology is not helpful in distinguishing secondary from primary schizophrenia. However, it is important to detect this organic-based subtype, since recognition and treatment of the primary disorder is needed. Therefore a set of standard investigations is needed to screen such cases when admitted with acute psychosis. The existence of secondary schizophrenias offers several potential pathways towards determining the cause of primary schizophrenia.

Acute Disease↗
PubMed1995

The temporal lobes, reversed asymmetry and the genetics of schizophrenia.

Mechanisms determining temporal lobe structural asymmetries may be involved in the pathogenesis of schizophrenia. To investigate the temporal lobes in familial schizophrenia, computed tomographic scans were obtained from 51 subjects (seven families). Enlargement of sylvian fissures and temporal lobe sulcal spaces was observed in family members with schizophrenia. The posterior one-third of the sylvian fissure was larger on the left side in subjects with schizophrenia, and larger on the right side in unaffected individuals. This disturbed pattern of posterior sylvian fissure asymmetry suggests that adjacent language regions may be affected in schizophrenia. An intermediate degree of disturbance in subjects who had schizophrenia-related illnesses or were obligate carriers suggests that genetic factors may be important determinants of temporal lobe asymmetries in familial schizophrenia.

Adult↗
PubMed1995

Brain morphology assessed by computed tomography in patients with geriatric depression, patients with degenerative dementia, and normal control subjects.

To determine whether patients with geriatric depression have specific alterations in brain morphology, internal (ventricles) and external (frontal, temporal, and parieto-occipital) components of the cerebrospinal fluid (CSF) spaces were examined. Planimetric measurements of computed tomographic (CT) scans from patients with geriatric depression were compared with measurements from two age- and sex-matched control groups: normal control subjects and patients with primary degenerative dementia. Scans of 34 patients (6 men, 28 women; mean age = 70.7 years) who met DSM-III-R diagnostic criteria for major depression, 29 patients with DSM-III-R primary degenerative dementia (8 men, 21 women; mean age = 71.2 years), and 43 nonpsychiatric control subjects (10 men, 33 women; mean age = 70.8 years) were evaluated. The areas of the frontal and parieto-occipital sulci, the Sylvian fissures, and the lateral and third ventricles were measured separately for the right and left hemispheres. Compared with the control subjects, patients with geriatric depression revealed a remarkable enlargement (up to 125%) of the left Sylvian fissure on several levels and a more subtle enlargement of the ventricles, cortical sulci, and right Sylvian fissure (20-50%). The laterality index differed significantly between depressed patients and normal control subjects (but not between the demented patients and the normal control group) only for the Sylvian fissure. Demented patients showed a considerable brain atrophy that affected all CSF components (enlargement of 30-160%) but the left temporal region was less affected than in the depressed patients. Compared with the findings in geriatric depression, ventricular enlargement was significant in dementia.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Reduced frontal and occipital lobe asymmetry on the CT-scans of schizophrenic patients. Its specificity and clinical significance.

Frontal and occipital lobe width were determined in the computed tomographic (= CT) scans of 135 schizophrenic patients, 158 neuropsychiatrically healthy and 102 psychiatric control subjects, including patients with affective psychosis, neurosis and schizoaffective psychosis. Most healthy right handed subjects demonstrate a relative enlargement of the right frontal as well as left occipital lobe compared to the opposite hemisphere. These normal frontal and occipital lobe asymmetries were selectively reduced in schizophrenics (f.: 5%, p < .0005; o.: 3%, p < .05), irrespective of the psychopathological subgroup. Schizophrenic neuroleptic non-responders revealed a significant reduction of frontal lobe asymmetry (3%, p < .05), while no correlation between BPRS-subscores and disturbed cerebral laterality could be detected. In sum the present study demonstrates disturbed cerebral lateralisation in schizophrenic patients supporting the hypothesis of interrupted early brain development in schizophrenia.

Adult↗
PubMed1995

Disturbed planum temporale asymmetry in schizophrenia. A quantitative post-mortem study.

The planum temporale of the temporal cortex was investigated post-mortem in 24 schizophrenic patients and 24 age- and sex-matched control subjects. Schizophrenic patients demonstrated a 20% volume reduction of the left planum temporale (p = 0.032), whereas on the right side, there was a trend for increase in male schizophrenics (+22%, p = 0.17), while in female patients the volume was moderately decreased (-6%, p = 0.74). The mean anterior-posterior diameter of the planum temporale was significantly reduced in the left hemisphere (-20%, p = 0.008), but unchanged on the right side. The asymmetry coefficients (Galaburda et al. (1987) Neuropsychologia 25, 853-868) for the planum temporale cortex volume (p = 0.02) and anterior-posterior diameter (p = 0.002) but not for mean area (p = 0.61) were significantly different between schizophrenics and control subjects. These data support the idea of disturbed cerebral laterality in schizophrenia. The implications of methodology and patient samples are discussed.

Adult↗
PubMed1994

Temporal lobe abnormalities in multigenerational families with schizophrenia.

Brain structure in familial schizophrenia was studied with computerized tomography in 42 individuals from six multigenerational families. Sulcal enlargement in the lateral temporal cortex, and ventricular and cisternal enlargement in the medial temporal region were observed in psychotic individuals compared to unaffected family members. Genetic factors in familial schizophrenia may exert part of their effect through determining or altering temporal lobe structure.

Adult↗
PubMed1994

The distribution of nitric oxide synthase immunoreactivity in the human brain.

Nitric oxide is a free radical which is produced in the brain and is thought to be the first of a new class of neural messenger molecules. It is postulated to act by inducing an increase in cyclic guanosine monophosphate levels in target cells. The neuronal isoform of nitric oxide synthase, the enzyme responsible for the calcium-dependent synthesis of nitric oxide from L-arginine, has been purified from brain homogenate. Using a specific polyclonal antibody, we have localized brain nitric oxide synthase to the cytosol of discrete neuronal subpopulations and glial elements. These include non-pyramidal cells in the cerebral cortex, pyramidal and non-pyramidal cells of the hippocampus, aspiny neurons of the corpus striatum, basket, Purkinje and granule cells in the cerebellum and neurons of various brain stem nuclei. The localization of nitric oxide-producing neurons in morphologically different and neurochemically diverse cell types suggests a widespread neuromodulatory role for nitric oxide in the central nervous system of man.

Adult↗
PubMed1994

In vivo morphometry of planum temporale asymmetry in first-episode schizophrenia.

Magnetic resonance imaging is a promising tool for in vivo analysis of the neuropathology underlying schizophrenia. One of the most consistent features emerging from the majority of published studies is the lateralization of pathological findings, and this has led to hypotheses of impaired hemispheric specialization in schizophrenia. In previous work, we have validated morphometry of supratemporal language-related cortex using high-resolution magnetic resonance imaging and analyzed the relation of the so defined planum temporale to functional parameters of hemispheric specialization. In the present study, we examined planum temporale structural asymmetry in first-episode schizophrenics. Asymmetry coefficients obtained in these patients did not differ significantly from those in equally right-handed controls and were not correlated to standard psychopathological measures. These data are contrasted with other studies reporting lateralized brain pathology in schizophrenia with special emphasis on methodological considerations in neuroimaging procedures.

Adult↗
PubMed1993

The neuropathology of schizophrenia: past and present.

Historical aspects of neuroanatomical schizophrenia research and recent findings in limbic and basal ganglia structures of schizophrenia are briefly reviewed. Then, results of volume measurements of these brain regions from 26 schizophrenics and 28 controls belonging to our new brain collection are presented. Volumes of the hippocampus, amygdala, stria terminalis and caudate were bilaterally significantly reduced, the internal pallidum showed a trend towards smaller volumes, while brain weight, putamen, nucleus accumbens and external pallidum were unchanged. The results give further evidence of subtle focal brain tissue reductions in schizophrenics. Finally, gaps in our present knowledge in the neuropathology of schizophrenia and some basic problems in this research field are discussed.

Adult↗
PubMed1992

Loss of sylvian fissure asymmetry in schizophrenia. A quantitative post mortem study.

The sylvian fissure is known to be one of the most asymmetric structures of the human brain. Sylvian fissure length was measured in post-mortem brains of 35 schizophrenic patients and 33 matched non psychiatric control subjects. The schizophrenics showed a significantly reduced length of the left sylvian fissure (-16%, p less than 0.0001) compared to the control subjects, while the right sylvian fissure length was unchanged. Sylvian fissure asymmetry (left/right ratio) was more reduced in male schizophrenics (-24%, p less than 0.001) than in female patients (-16%, p less than 0.03). This finding is consistent with several post-mortem and MRI studies showing left temporal lobe pathology in a significant proportion of patients and may indicate that schizophrenia is a disorder of early neurodevelopment causing impaired cerebral lateralization.

Adult↗
PubMed1992

Increased prevalence of the cavum septum pellucidum in magnetic resonance scans and post-mortem brains of schizophrenic patients.

A cavum septum pellucidum (CSP) has been regarded as an incidental finding of little clinical importance. However, an association between this developmental anomaly and a diagnosis of psychosis has previously been reported. We determined the prevalence of the CSP in parallel studies of brain scans obtained with magnetic resonance (MR) imaging and in the post-mortem brains of schizophrenic patients compared with normal controls. We found a significantly increased prevalence of the CSP in both the MR scans and post-mortem brains of schizophrenic patients compared with controls. In the MR study, 17 of 81 (21%) schizophrenic patients but only 1 of 46 (2%) control subjects had a CSP. In the post-mortem study, 17 of 28 (61%) schizophrenic patients and 12 of 39 (31%) normal controls had a CSP. The increased prevalence of a CSP in schizophrenic patients further indicates that anomalous development of the limbic system is an important aspect of this disorder.

Adult↗