Biomedical subjects
Publications and source records attributed to R Gruen.
A patient with communicating hydrocephalus had recurrent papilledema during episodes of thyrotoxicosis. Increased intracranial pressure was documented and, as reflected by the severity of the papilledema, fluctuated in proportion to the thyroid hormone levels.
Platelet monoamine oxidase activity (MAO) was determined in 39 unmedicated chronic schizophrenic patients and 88 normal control subjects. Platelet MAO activity did not distinguish paranoid from nonparanoid patients or patients who met Taylor and Abrams criteria for narrowly defined schizophrenia from other schizophrenics. Enzyme activity was not related to either prognostic scores or age at onset of illness. MAO activity was decreased in patients compared to controls, and was lower in males than in females. Our findings indicate that clinical phenomenology, as defined in the present study, is of limited use in identifying biological subtypes of schizophrenia with deviant platelet MAO activity.
Age and sex effects on 3H-imipramine platelet binding sites were determined in 58 normal subjects (27 males, 31 females). The correlation of age with either the maximal imipramine binding (Bmax) or the dissociation constant (Kd) was statistically nonsignificant in both males and females. Males did not differ from females in Bmax and Kd values. The implications for psychiatric research were discussed.
The occurrence of stressful life events in relation to illness onset and family history of schizophrenia was assessed in 52 chronic schizophrenic patients. Severe or extreme premorbid stress was present in 15.4% of the patients. 'Low stress' patients were indistinguishable from 'high stress' patients with respect to the familial rate of schizophrenia and other 'spectrum' disorders.
The authors determined the erythrocyte catechol O-methyltransferase (COMT) activity of 38 chronic schizophrenic patients, 69 of their first-degree relatives, and 39 normal controls. COMT activity did not distinguish patients from controls. Within families, COMT activity was not associated with schizophrenia spectrum disorders. The data suggest that COMT activity is not an indicator of vulnerability to schizophrenia.
Platelet monoamine oxidase (MAO) activity, determined in 102 patients with chronic schizophrenia, 223 first-degree relatives, and 88 normal control subjects, was shown to be a heritable and stable trait and was significantly lower in patients than in normal control subjects. Within families, MAO activity distinguished ill from well relatives. However, the considerable overlap in enzyme activity between affected and unaffected individuals limits the usefulness of low MAO activity as a major risk factor in schizophrenia.
Plasma amine oxidase (PAO) activity was studied in 52 chronic schizophrenics, 130 first-degree relatives, and 36 normal control subjects. Enzyme activity was shown to be a heritable and stable characteristic. Age and sex effects were not present. Patients had lower PAO activity than did control subjects, although the difference fell short of statistical significance. Within families, reduced PAO activity was associated with schizophrenia spectrum disorders.
Platelet recovery and activity of platelet monoamine oxidase (MAO) and plasma amine oxidase (PAO) were determined using different centrifugation procedures (125 g for 15 min vs. 600 g for 2.5 min) and anticoagulants. With either centrifugation procedure, the use of ethylenediaminetetraacetate (EDTA) as anticoagulant resulted in higher platelet yields and MAO activity compared to acid-citrate-dextrose (ACD). However, PAO activity was lower with EDTA as anticoagulant than with ACD. There was a trend toward higher platelet yields and higher activity levels of MAO and PAO with the 125 g centrifugation method than with the 600 g technique regardless of the anticoagulant used. The implications for MAO studies in psychiatric research were discussed.
Age-of-onset data were gathered on 93 chronic schizophrenic probands and 57 affected (mainly schizotypal) siblings. 55% of affected individuals were ill before age 20 and 14% had their onset before age 14. The risk period for schizophrenia and schizotypal personality disorders terminated at age 40. Age-of-onset did not distinguish paranoid from nonparanoid schizophrenics, or definite from probable schizotypal personalities. Schizophrenic and schizotypal subjects were similar in their age-of-onset patterns. Sex effect on age-of-onset was not present. A square-root normal distribution gave the best fit to the data. The implications of these findings for schizophrenia research were discussed.
The types and expectancy of mental disorders in the siblings of 74 probands with chronic schizophrenia were examined. The siblings were classified according to whether 1) both parents had schizotypal personality disorder, 2) one parent had the disorder and one was normal, or 3) both parents were normal. Siblings whose parents both had the disorder were at significantly greater risk for schizophrenia and schizotypal personality disorder than siblings with at least one normal parent. Similarly, the expectancy of schizotypal personality disorder alone and combined with schizophrenia was higher among siblings with one parent with the disorder than in siblings with two normal parents. The data suggest that schizotypal traits may be genetically related to schizophrenia.
High-affinity 3H-imipramine binding to platelets was determined in 15 drug-free unipolar depressed women and 15 normal controls. The maximum number of binding sites (Bmax) was lower in the depressed population, but the difference fell short of statistical significance (p = 0.07). The dissociation constant for imipramine binding (Kd) was found to be significantly lower among patients than in controls (p = 0.02). The various factors that can affect the in vitro platelet assay, and the implications for affective disorder research, were discussed.
Five sets of criteria for the diagnosis of schizophrenia were compared on 47 hospitalized patients who fit New York Research Diagnostic Criteria (RDC) for chronic schizophrenia. The other diagnostic systems used were the Flexible System. Feighner Criteria, New Haven Schizophrenia Index (NHSI), and Taylor-Abrams (TA) Criteria. The NSHI, the broadest system examined, fit all of the patients studied. In contrast, only 30 patients (63% of the sample) were diagnosed schizophrenic using TA Criteria. When the Strauss-Carpenter prognostic scale was used, patients who fit TA Criteria for schizophrenia did not differ in the prognostic scores from the remainder of the sample. In addition, the two groups did not differ in the familial rate of schizophrenia spectrum disorders. The usefulness of narrow versus broad diagnostic criteria in schizophrenia research is discussed.
Activity levels of platelet monoamine oxidase (MAO) and plasma amine oxidase (PAO) were determined in eight chronic schizophrenic patients who had been treated with neuroleptic drugs for 3 months. The mean reduction in platelet MAO activity was 18.6%. The extent of decrease was statistically significant. The reduction in enzyme activity was unrelated to serum iron levels. PAO activity was unaltered. The implications for schizophrenia research are discussed.
Data on schizoaffective illness, schizophrenia and affective disorders were gathered on first-degree relatives of schizoaffective probands and matched controls (bipolars, unipolars and schizophrenics). The familial pattern of affective and schizophrenic subtypes of schizoaffective disorder resembled the familial pattern of affective and schizophrenic probands, respectively. The overall risk for the spectrum of schizoaffective and affective disorders was higher among relatives of schizoaffective-manic as compared to relatives of schizoaffective-depressive probands, although the difference fell short of significance. When tested for consistency with multiple threshold hypotheses of genetic transmission, schizoaffective illness did not qualify as either a more extreme form of affective illness nor as a disorder that occupies an intermediate position between bipolar and unipolar disorders or is genetically milder than affective disorder. The implications of diagnostic subtyping for genetic research in the major psychoses were discussed.
Plasma dopamine-beta-hydroxylase (DBH) activity was determined in 8 chronic schizophrenic patients following neuroleptic treatment for 2 months. Enzyme activity was decreased by 13.7 +/- 3.4% (mean +/- SD). The difference from pre-drug levels was not statistically significant. The reduction in DBH activity stabilized after the 1st month of treatment and was unrelated to neuroleptic drug load.
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To test the hypothesis that schizophrenia can be differentiated on the basis of family history, the authors compared two matched samples of 20 patients each, distinguished by the presence or absence of family history of schizophrenia. Family history was not associated with either onset characteristics, symptom picture, phenomenological subtypes of schizophrenia, prognostic indicators or global assessment score for psychosocial functioning.
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