PubMed Health⌕ Search

Biomedical subjects

J B Lohr

Publications and source records attributed to J B Lohr.

At least 37 records · Page 2Linked to original sources
PubMed1995

Motor asymmetry, a neurobiologic abnormality in the major psychoses.

A century after Kraepelin, clinical scientists still debate whether the major functional psychoses, schizophrenia and bipolar illness, are separate disease entities or fall on opposite ends of a spectrum of severe psychopathology. In a study of control of hand-muscle force, patients with schizophrenia and bipolar affective disorder exhibited opposite asymmetries, with greater right-hand dyscontrol in schizophrenia, and greater left-hand dyscontrol in bipolar disorder. This suggests that there is greater pathological involvement of the dominant hemisphere in schizophrenia and of the non-dominant hemisphere in bipolar disorder.

Adult↗
PubMed1995

Free radical involvement in neuropsychiatric illnesses.

Free radicals are highly reactive chemical species with an unpaired electron, and their formation is catalyzed by transition metals like iron, copper, and manganese. There have been numerous studies linking free radical damage with neuropsychiatric illnesses, including several psychiatric and motor disorders, raising the possibility that antioxidant strategies might serve a neuroprotective role for some conditions. The illnesses studied include tardive dyskinesia, schizophrenia, Parkinson's disease, and Alzheimer's disease. Although oxidative mechanisms may play a role in these conditions, further studies are necessary to define their involvement, and to determine the extent to which antioxidants may partially alleviate or prevent some of these conditions.

Free Radicals↗
PubMed1994

Pharmacists' role in clozapine therapy at a Veterans Affairs medical center.

A program in which pharmacists have an active role in prescribing and dispensing psychoactive drugs is described. The Department of Veterans Affairs (VA) has established a National Clozapine Coordinating Center (NCCC) that must approve all clozapine therapy in VA medical centers. Clinical and demographic information is required for all new patients, and weekly status reports are required throughout clozapine therapy. To comply with NCCC requirements, pharmacists with specialized training in psychopharmacology organized a clozapine clinic at one VA medical center, in conjunction with the psychiatry service. The pharmacists screen potential candidates for clozapine therapy and forward the required information to the NCCC for approval. During treatment, they ensure that necessary laboratory tests and clinical evaluations are performed for inpatients and recommend dosage adjustments to the psychiatry residents. The pharmacists see outpatients receiving clozapine weekly to monitor and record vital signs, laboratory results, and response to therapy and make dosage adjustments accordingly. For both inpatients and outpatients, the pharmacists send weekly patient evaluations to the NCCC. Pharmacists at a VA medical center provide direct care to patients receiving clozapine and help their institution comply with the stringent therapy-monitoring requirements of the NCCC.

California↗
PubMed1994

A disturbance in the control of muscle force in neuroleptic-naive schizophrenic patients.

The voluntary motor disturbances found among many schizophrenic patients consist of motor incoordination, disturbed pursuit tracking, difficulty following movement sequences, desynchronized tapping, and a myriad of neurologic soft signs. The problem with many of these observations is that it is extremely difficult to distinguish movement disorders related to neuroleptic treatment from those that may have occurred spontaneously. The aim of the present study was to examine potential disturbances in the voluntary control of steady-state force in neuroleptic-naive schizophrenic patients and normal comparison subjects. Twenty-one patients and 21 age- and gender-matched comparison subjects were studied. Spectral analyses of hand force instability revealed a significant difference between patients and comparison subjects. In 52 of the patients, the disturbance in the control of force exceeded the 95th percentile of the comparison mean. Degree of force instability was correlated with positive but not negative symptoms of schizophrenia. These findings suggest that schizophrenic patients may exhibit a disturbance in the control of muscle force that cannot be attributed to the neuroleptic effects of antipsychotic medication. The pattern of disruption, characterized by abnormal spectral energy within the 1.5 to 3.0 Hz range, suggests a motor disturbance that resembles tardive dyskinesia. Implicit within these findings of neuroleptic naive patients is the possibility that disturbances in the control of isometric force may represent spontaneous dyskinesia.

Adult↗
PubMed1994

Serum-soluble interleukin-2 receptors in neuroleptic-naive schizophrenic subjects and in medicated schizophrenic subjects with and without tardive dyskinesia.

There is a growing body of literature suggesting that some schizophrenic subjects have evidence of immune activation. One marker that has been consistently elevated in studies is the serum-soluble interleukin-2 receptor (SIL-2R). This article reports the results of 2 experiments: the first compares concentrations of serum SIL-2R in neuroleptic-naive schizophrenic patients and matched controls, and the second study contrasts serum SIL-2R concentrations in medicated schizophrenic subjects with and without tardive dyskinesia. Serum SIL-2R concentrations were elevated in neuroleptic-naive schizophrenic subjects as compared with controls (1705.7 (SD 1124.2) U/ml vs 739.8 (SD 325.5) U/ml). Medicated subjects with tardive dyskinesia had increased serum SIL-2R levels (2385.5 (SD 1822.0) U/ml) compared with medicated subjects without tardive dyskinesia (1259.6 (SD 1365.3) U/ml). Thus, elevations in serum SIL-2R levels are present prior to neuroleptic treatment, and there may be an association between serum SIL-2Rs and tardive dyskinesia.

Adult↗
PubMed1994

A treatment outcome study of community-based residential care.

OBJECTIVE: The authors describe two psychosocially oriented community residential facilities for patients with persistent and severe mental disorders and multiple failures at community tenure, and they report a retrospective study designed to evaluate treatment outcomes of program residents. METHODS: The study employed a retrospective single-group repeated-measures design to evaluate 104 patients who completed the one-year follow-up. One-year mean number of admissions to and days in a hospital or crisis center during the two years before program entry were compared with mean admissions and days for the follow-up year; employment status, living status, and Global Assessment of Functioning (GAF) Scale scores at program entry and at one-year follow-up were also compared. Thirteen sociodemographic and clinical variables were individually tested for association with outcome. RESULTS: Hospital and crisis center admissions and days were significantly reduced during the follow-up year. At one-year follow-up, a significantly greater proportion of patients were employed and living independently, and fewer were homeless. GAF scores were significantly higher. No significant correlations between outcome and sociodemographic and clinical variables were found. CONCLUSIONS: Despite design limitations of the study, the findings suggest that psychosocial residential treatment models can offer cost-effective and clinically efficacious care to persistently mentally ill patients.

Adult↗
PubMed1993

Minor physical anomalies in schizophrenia and mood disorders.

The Waldrop Physical Anomaly Scale was used to assess the prevalence of minor physical anomalies in three groups: schizophrenia patients (n = 118), patients with mood disorders (n = 33), and normal controls (n = 31). Patients with schizophrenia had significantly more anomalies than controls. Patients with mood disorders did not have significantly different anomaly scores than schizophrenia patients or controls. Patients with tardive dyskinesia (TD) had significantly more anomalies than those without TD. Physical anomalies in the schizophrenia group were not found to be related to severity of psychopathology, age of onset, positive or negative schizophrenic symptoms, or socioeconomic status.

Abnormalities, Multiple↗
PubMed1993

Extrapyramidal motor abnormalities associated with late-life psychosis.

Studies of extrapyramidal motor function in patients with schizophrenia have contributed to our understanding of the phenomenology and therapeutic outcome associated with neuroleptics. An increasing body of literature suggests that extrapyramidal motor abnormalities associated with schizophrenia may be linked to the pathophysiological mechanisms responsible for schizophrenia. Similarly, it has been documented that the extrapyramidal system may be involved in motor abnormalities in patients with Alzheimer's disease (AD). The present study was undertaken to examine motor function in schizophrenia and AD patients with psychosis. Quantitative instrumental procedures were used to examine rigidity, tremor, and bradykinesia in 13 neuroleptic-naive patients with schizophrenia, 13 AD patients with psychosis, and 26 age-comparable controls. Both schizophrenia and AD patients had significantly higher tremor and rigidity scores than did normal subjects. This comparative study of schizophrenia and AD patients with psychosis suggests that the effect of dementia in patients with psychosis is to prolong movement time, whereas abnormal parkinsonian postural tremor tends to be associated with psychosis in the absence of dementia.

Aged↗
PubMed1993

Worsening of postural tremor in patients with levodopa-induced dyskinesia: a quantitative analysis.

Some investigators have proposed that Parkinson's disease (PD) patients often exhibit a worsening of tremor before the emergence of levodopa-induced dyskinesia (LDD). It is not clear, however, whether the presence of tremor depends on the severity of dyskinesia, nor is the precise time course of tremor relative to dyskinesia well understood. This report describes an objective study of the relationship between postural tremor and dyskinesia in eight PD patients who showed signs of choreoathetoid hand movements after a single dose of levodopa. Spectral analysis of sustained hand force provided an objective and sensitive method of detecting worsening of tremor in patients with LDD. Severity of clinical symptoms was highly correlated with severity of dyskinesia. Six of the patients exhibited increased tremor amplitude within 45 min of exposure to levodopa, with two of the six patients experiencing bilateral and four of the six having unilateral worsening of postural tremor. Tremor was more severe on the side with the more severe dyskinesia. These findings provide objective support for the notion that dyskinesia and postural tremor may stem from a common pathophysiologic mechanism.

Aged↗
PubMed1993

Cortical-striatal-thalamic circuits and brain glucose metabolic activity in 70 unmedicated male schizophrenic patients.

OBJECTIVE: The cortical-striatal-thalamic circuit modulates cognitive processing and thus may be involved in the cognitive dysfunction in schizophrenia. The imaging of metabolic rate in the structures making up this circuit could reveal the correlates of schizophrenia and its main symptoms. METHOD: Seventy male schizophrenic patients underwent [18F]-fluorodeoxyglucose positron emission tomography after a period of at least 4 weeks during which they had not received neuroleptic medication and were compared to 30 age-matched male normal comparison subjects. RESULTS: Analyses revealed decreased metabolism in medial frontal cortex, cingulate gyrus, medial temporal lobe, corpus callosum, and ventral caudate and increased metabolism in the left lateral temporal and occipital cortices in the schizophrenic cohort. Consistent with previous studies, the schizophrenic group had lower hypofrontality scores (ratios of lateral frontal to occipital metabolism) than did comparison subjects. The lateral frontal cortical metabolism of schizophrenic patients did not differ from that of comparison subjects, while occipital cortical metabolism was high, suggesting that lateral hypofrontality is due to abnormalities in occipital rather than lateral frontal activity. Hypofrontality was more prominent in medial than lateral frontal cortex. Brief Psychiatric Rating Scale (BPRS) scores, obtained for each schizophrenic patient on the scan day, were correlated with regional brain glucose metabolic rate. Medial frontal cortical and thalamic activity correlated negatively with total BPRS score and with positive and negative symptom scores. Lateral frontal cortical metabolism and hypofrontality scores did not significantly correlate with negative symptoms. Analyses of variance demonstrated a reduced right greater than left asymmetry in the schizophrenic patients for the lateral cortex as a whole, with simple interactions showing this effect specifically in temporal and frontal cortical regions. CONCLUSIONS: Low metabolic rates were confirmed in medial frontal cortical regions as well as in the basal ganglia, consistent with the importance of the cortical-striatal-thalamic pathways in schizophrenia. Loss of normal lateralization patterns was also observed on an exploratory basis. Correlations with negative symptoms and group differences were more prominent in medial than lateral frontal cortex, suggesting that medial regions may be more important in schizophrenic pathology.

Adolescent↗
PubMed1993

Parkinsonism in neuroleptic-naive schizophrenic patients.

OBJECTIVE: Previous studies in schizophrenia have identified abnormalities involving the basal ganglia, but the contribution of neuroleptics to the motor system abnormalities in schizophrenia is usually a confounding factor. This study addressed the issue of whether parkinsonism, a reflection of dopaminergic hypofunction, occurs in schizophrenia per se. METHOD: Clinical ratings and quantitative instrumental measures of parkinsonian rigidity, tremor, and bradykinesia were obtained in 24 neuroleptic-naive schizophrenic patients and 24 age- and gender-matched comparison subjects. RESULTS: According to the clinical ratings, 21% of the schizophrenic patients had rigidity and 12% had bradykinesia, in contrast to none of the normal comparison subjects. With the use of instrumental measures, rigidity and tremor were observed in 29% and 37%, respectively, of the schizophrenic patients, compared to 4% and none in the normal comparison group. The schizophrenic patients also exhibited greater right-side than left-side parkinsonism. CONCLUSIONS: The findings suggest that extrapyramidal motor signs may be part of schizophrenia proper and that some patients with schizophrenia have left striatal hypodopaminergia unrelated to neuroleptic treatment.

Adult↗
PubMed1992

Sensorimotor disinhibition in Parkinson's disease: effects of levodopa.

It has been known for some time that patients with Parkinson's disease (PD) have difficulty executing simultaneous motor acts, yet the pathophysiology underlying this impairment remains uncertain. We examined the possibility that these dual-task deficits stem from defective sensorimotor mechanisms producing interference between the motor programs underlying the two tasks. Patients with PD and normal control subjects were tested on their ability to maintain steady-state force with one hand while performing a force-reaction time task with the other hand. Although performance was worse on the dual-task than on the single-task condition for both subject groups, only the patients with PD demonstrated significant interference between the two tasks. The interference across tasks improved in 87% of the patients with PD when tested after treatment with carbidopa/levodopa (Sinemet). These findings support the contention that, in patients with PD, disturbances in the execution of simultaneous motor performance may be due to sensorimotor disinhibition.

Carbidopa↗
PubMed1992

Study of neuropathologic changes in the striatum following 4, 8 and 12 months of treatment with fluphenazine in rats.

Persistent tardive dyskinesia is a serious side effect of long-term treatment with neuroleptics. Although striatal pathologic changes are believed to underlie this potentially irreversible iatrogenic syndrome, the nature of the neuroleptic-induced neuropathology is unclear. In the present study, we treated rats with either vehicle or fluphenazine decanoate (5 mg/kg, IM) every 2 weeks for 4, 8 or 12 months. Four to nine weeks after the last injection, the animals were sacrificed and the density of cells in the central part of the striatum was measured with a computerized image-analysis system. The control and experimental animals did not differ in body weight with 4 and 8 months of treatment, but the rats treated with fluphenazine for 12 months had significantly lower body weights than comparable controls. Four months of neuroleptic use produced no significant neuropathologic changes. The animals treated with fluphenazine for 8 months had a significantly lower density of the large neurons. In the 12-month-treated group, there was no significant difference between the control and experimental animals, probably because of a 'floor effect': the density of the large neurons was significantly lower in the 12-month-treated compared to the 8-month-treated control rats.

Animals↗
PubMed1992

Cerebrospinal fluid and serum levels of neuron-specific enolase in patients with schizophrenia.

Some patients with schizophrenia appear to have brain abnormalities, including enlarged third and lateral ventricles and reduced volumes of temporal lobe structures. These abnormalities could be attributed to a developmental abnormality or a neurodegenerative process. Neuron-specific enolase (NSE), a protein that is found primarily in neurons and neuroendocrine cells, has been used as an index of neuronal damage or degeneration. Levels of NSE in cerebrospinal fluid (CSF) and serum from 50 patients with acute and chronic schizophrenia were compared with those in normal and neurological control subjects. A double-antibody, solid phase iodinated radioimmunoassay was used to determine NSE levels. There was no evidence of elevated levels in patients with schizophrenia, whereas control subjects with neurological illnesses had increased levels of NSE in CSF. Because NSE is rapidly cleared from CSF, however, elevated levels could have been missed. Unmedicated patients tended to have lower levels than medicated patients.

Adult↗
PubMed1992

Smoking and schizophrenia.

Several studies have shown that patients with schizophrenia have an extremely high prevalence of smoking, almost 90%, compared to only 33% in the general population and 45-70% in patients with other psychiatric diagnoses. The reasons for the high prevalence of smoking among schizophrenics is unknown, but it is likely that smoking behavior in schizophrenia may be a complex process, related to numerous interrelationships between the psychopathological, biochemical, and neuropharmacological aspects of smoking and of schizophrenia.

Antipsychotic Agents↗
PubMed1992

A monozygotic mirror-image twin pair with discordant psychiatric illnesses: a neuropsychiatric and neurodevelopmental evaluation.

One piece of genetic evidence for the biological distinctness of schizophrenia and bipolar illness is the rarity of monozygotic twin pairs in which one twin suffers from schizophrenia and the other from bipolar disorder. The authors describe a pair of monozygotic mirror-image twins with discordant diagnoses, schizophrenia in one twin and bipolar or schizoaffective disorder in the other.

Adult↗
PubMed1992

Quantitative instrumental measurement of tardive dyskinesia: a review.

In this paper we review currently available quantitative instrumental techniques for the assessment of tardive dyskinesia (TD). We discuss the advantages and disadvantages of the use of accelerometers, electromyography, force gauges, position transducers, and Doppler ultrasound from both a diagnostic and a utilitarian perspective. Data obtained using these techniques appear to correlate significantly with patient scores on clinical rating scales. In some cases, the use of these techniques has facilitated the detection of subclinical dyskinesia and helped to differentiate TD from other movement disorders. We believe that a review of these qualitative techniques will be of interest to the clinician, as well as to investigators involved in studying TD.

Dyskinesia, Drug-Induced↗