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W F Gattaz

Publications and source records attributed to W F Gattaz.

104 records · Page 6Linked to original sources
PubMed1982

[The histocompatibility system in schizophrenia].

Various diseases with a noticeable autoimmune component and frequent occurrence within one family show a statistically significant correlation with specific human leucocyte antigens (HLA). This correlation was also found in studies of HLA in psychiatric disorders. However, results have been contradictory. The phenotype frequencies of HLA specificities were investigated in 100 schizophrenic patients and 472 controls from the same geographic area in Germany. The frequency of HLA-B27 was significantly increased in the patient group as a whole and in the subgroups of paranoid patients, chronic schizophrenics, patients with poor prognosis and in patients with the onset of the disease before the age of 20 years. In the latter three subgroups an elevated incidence of HLA-A9 was also found. The combination A9-B27 was detected in 0,63% of our control group and in 7% of the patients. Of these patients 85,7% were chronic paranoid patients with poor prognostic features. The present study indicates a possible marker of genetic heterogeneity in schizophrenia and gives support to the possibility of using HLA typing in genetic studies of schizophrenia as well as in the differential diagnosis and prognosis. Moreover, in spite of the statistical significance of our findings, the fact that the associations are well below 100% indicates that other factors (presumably environmental) must be involved in the etiology of the disease.

Adolescent↗
PubMed1981

HLA antigens and schizophrenia: a pool of two studies.

Results from two studies on HLA antigens in schizophrenic patients were pooled and analyzed. A statistically significant difference appeared in the frequency for HLA-B27, which was increased in the patient group (n = 164) as compared to the controls (n = 585). The strong correlation between this antigen and some forms of arthropathies and the fact that arthropathies and schizophrenia very seldom occur in the same individual suggest that HLA-B27 could serve as a genetic marker for both diseases. The development of either one or the other may depend upon the interplay between the genetic marker (HLA-B27) and other biological and environmental factors. In addition to the potential value of HLA-B27 as a marker for vulnerability to schizophrenia, the human leucocyte antigens may also serve to differentiate between various subtypes of the illness.

Genetic Markers↗
PubMed1981

Platelet MAO activity and personality characteristics. A study in schizophrenic patients and normal individuals.

Low levels of platelet monoamine oxidase have been found in schizophrenic and bipolar depressive patients. The enzyme activity seems to correlate negatively with certain personality traits (social activity, sensation seeking, hypomania, positive affect and monotony avoidance) which are correlated to some extent with the score "extraversion" from the Eysenck Personality Questionnaire (EPQ). The present study was carried out in an attempt to investigate further the possible correlation between platelet MAO activity and the personality traits measured by the EPQ. 41 schizophrenic patients and 20 healthy probands were blindly examined for platelet MAO activity and personality characteristics. The enzyme activity was found to correlate negatively with the extraversion score in patients and healthy probands, which is in agreement with the data from other studies. This correlation is discussed and a hypothesis suggested.

Adult↗
PubMed1981

Low platelet MAO activity and schizophrenia: sex differences.

The authors compared platelet monoamine oxidase activity in schizophrenic patients and normal controls. A significant reduction in the enzyme activity was found in the male schizophrenic patients but not in the females. No differences were detected among the subgroups of schizophrenia. Sources of bias and the possible mechanism for the findings are discussed.

Adult↗
PubMed1981

[HLA, schizophrenias and arthropathies].

Significantly more individuals with human leucocyte antigens (HLA) A9 and B27 have been identified in the group of chronic paranoid schizophrenics with early onset of the disease. It is known that individuals with HLA B27 have a markedly increased risk to fall ill from arthropathies (i.e. Bechterew's disease). Generally, it seems extremely rare that arthropathies and schizophrenia occur together in the same person. In 16 chronic paranoid schizophrenics with HLA B27 no form of arthropathy and in 288 arthropathic patients no case of schizophrenia could be detected (evidenced in a psychiatric case register). Furthermore in 131 arthropathic patients with HLA B27 no psychiatric disease (except one feeble-minded and one with alcohol problems) could be identified. On the other hand, in the group of arthropathic patients without HLA B27 the incidence of psychiatric diseases was 5 times higher than in the group with HLA B27 and so comparable to the morbidity of the normal population. It is conceivable that HLA B27 is a 'genetic marker' for arthropathy as well as for a defined subgroup of schizophrenia. These data agree with the hypothesis that schizophrenia and arthropathies are mutually exclusive in one individual.

Adult↗
PubMed1980

The HLA system and schizophrenia. A study in a German population.

Various diseases with a noticeable autoimmune component and frequent occurrence within one family show a statistically significant correlation with specific human leukocyte antigens (HLA). This correlation was also shown in studies of HLA in psychiatric disorders. However, results have been contradictory. The phenotype frequencies of HLA specificities were investigated in 100 schizophrenic patients and 472 controls from the same geographic area in Germany. The frequency of HLA B27 was significantly increased in the patient group as a whole (P=0.017) and in the subgroups of paranoid patients (P=0.005), chronic schizophrenics (P less than 0.001), patients with poor prognosis (P less than 0.001), and in patients with onset of the disease before the age of 20 years (P=0.004). In the latter three groups an elevated incidence of HLA A9 was also found. The combination A9-B27 was detected in 0.63% of our control group and in 7% of the patients (P less than 0.001). Of these patients 85.7% were chronic paranoid patients with poor prognostic features. This study gives support to the possibility of using HLA typing in genetic studies of schizophrenia, as well as in the differential diagnosis and prognosis.

Adolescent↗
PubMedDate not supplied

The value of REM sleep parameters in differentiating Alzheimer's disease from old-age depression and normal aging.

Pseudodementia as a common trait in elderly depressives presents a major problem in gerontopsychiatry, especially for the differential diagnosis between Old-Age Depression (OAD) and Dementia of the Alzheimer Type (DAT). The present polysomnographic study examined parameters of sleep continuity, sleep architecture, and REM sleep to differentiate DAT from OAD. The investigation was based on the theoretical framework of the cholinergic-aminergic imbalance model of depression, the cholinergic deficit hypothesis of Alzheimer's disease and the reciprocal interaction model of Non-REM/REM sleep regulation, according to which REM sleep parameters should have high discriminative value to differentiate OAD and DAT. We investigated 35 DAT patients, 39 OAD patients and 42 healthy controls for two consecutive nights in the sleep laboratory. The DAT patients were in relatively early/mild stages of the disease, the severity of depression in the OAD group was moderate to severe. Depressed patients showed characteristic 'depression-like' EEG sleep alterations, i.e. a lower sleep efficiency, a higher amount of nocturnal awakenings and decreased sleep stage 2. Sleep continuity and architecture in DAT was less disturbed. Nearly all REM sleep measures differentiated significantly between the diagnostic groups. OAD patients showed a shortened REM latency, increased REM density and a high rate of Sleep Onset REM periods (SOREM), whereas in DAT REM density was decreased in comparison to control subjects. REM latency in DAT was not prolonged as expected. To assess the discriminative power of REM sleep variables a series of discriminant analyses were conducted. Overall, 86% of patients were correctly classified, using REM density and REM latency measures. Our findings suggest that REM density as an indicator of phasic activity appears to be more sensitive as a biological marker for the differential diagnosis of OAD and DAT than REM latency. The results support the role of central cholinergic neurotransmission in REM sleep regulation and the pathogenesis of DAT and OAD.

Aged↗
PubMedDate not supplied

Cholesterol modulates the membrane-disordering effects of beta-amyloid peptides in the hippocampus: specific changes in Alzheimer's disease.

Cholesterol represents an important determinant of the physical state of biological membranes. In Alzheimer's disease (AD) brains, specific changes in the distribution of cholesterol and its membrane-ordering effects take place. In the present study, membrane fluidity was investigated at the level of the hydrocarbon core and of the heads of the phospholipid bilayers using two different fluorescent probes. Hippocampal membranes of AD brains showed a reduced fluidity in the hydrocarbon core region only. Fluidity was correlated with the cholesterol content in AD and control membranes. Aggregated beta-amyloid peptides (Abeta) disrupted brain membrane structure in AD patients and controls in the same fashion. However, this effect was correlated with the cholesterol content in AD membranes only. It is suggested that in AD the brain becomes specifically sensitive for the modulation by membrane-bound cholesterol of the membrane-disturbing and ultimately neurotoxic properties of Abeta.

Alzheimer Disease↗
PubMedDate not supplied

Cortical NMDA receptor properties and membrane fluidity are altered in Alzheimer's disease.

NMDA receptor density as measured by the specific binding of [3H]MK 801 was significantly decreased (about 20%) in the frontal but not in the parietal cortex of postmortem brain samples of Alzheimer's disease (AD) patients (n = 21), when compared with control brains (n = 20). Membrane fluidity was not altered in the frontal cortex samples, but was slightly reduced in the parietal cortex samples of the AD patients. Since AD-specific histopathological changes (densities of senile plaques and neurofibrillary tangles) were about similar in both areas, it is concluded that the reductions of NMDA receptor densities in the frontal cortex is independent of AD-specific histopathological changes and of changes of membrane fluidity.

Aged↗