Biomedical subjects
H Stewart
Publications and source records attributed to H Stewart.
Reliability of transcranial magnetic stimulation for mapping the human motor cortex.
Motor mapping using transcranial magnetic stimulation has been applied to the study of adaptive and restorative mechanisms of the motor cortex. To date, the reproducibility of mapping techniques has yet to be investigated in detail and/or confirmed. We report a technique used to map the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) motor cortices of 6 normal volunteers, each studied on 2 occasions separated by several weeks (range of 21-132 days). APB and ADM results were analyzed separately, with area and volume characteristics subjected to analysis of variance. Coefficients of variation, which should be low, ranged from 14% to 37% and coefficients of reliability, which should be high, ranged from 63% to 94%, indicating that the described technique for motor mapping is responsible.
Cause-specific mortality in long-term survivors of breast cancer who participated in trials of radiotherapy.
PURPOSE: To examine long-term cause-specific mortality in patients irradiated for breast cancer as part of a randomized clinical trial. PATIENTS AND METHODS: We studied all available information from randomized trials initiated before 1975 in which radiotherapy was the randomized option and surgery was the same for both treatment arms. Eight such trials were identified. RESULTS: The increased all-cause mortality rate in 10-year survivors previously reported is no longer significant, although a numerical difference in favor of non-irradiated patients remains. This result was strongly influenced by the earliest trials, and more recent trials have found a nonsignificant net benefit in overall mortality associated with radiation therapy. An excess of cardiac deaths was apparent in both early and more recent trials (P < .001), but this was offset by a reduced number of deaths due to breast cancer, especially in more recent trials. CONCLUSION: The reduction of breast cancer deaths suggests that radiation therapy may have a value beyond the clearly established improvements obtainable for local control. Use of techniques that minimize cardiac dose is important in reducing the risks of adjuvant radiotherapy, especially in good-prognosis patients.
Exciton-related lasing mechanism in ZnSe-(Zn,Cd)Se multiple quantum wells.
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Receiver operating characteristic curve analysis in the prediction of carpal tunnel syndrome: a model for reporting electrophysiological data.
Receiver operating characteristic (ROC) curves were used to predict the risk of carpal tunnel syndrome (CTS). Patients were classified clinically as: (1) normal exam and no symptoms (169 hands); (2) having a motor and/or sensory deficit typical of CTS (115 hands); (3) having a history characteristic of CTS (156 hands); and (4) nondiagnostic symptomatology (122 hands). Electrophysiological studies consisted of median and ulnar motor, sensory, and palmar measurements. Group mean values for group 1 differed significantly from groups 2 and 3 (not 4) for all measurements, but values overlapped considerably. Median distal motor latency (DMML) combined with median-ulnar palmar latency differences (MUPLD) had significantly superior discriminant power than other measurements and correlated highly for all groups (r values = 0.71-0.73). These variables were used to construct ROC curves and prediction tables. The approach used allows one to assign a percentage risk of having a CTS and can be used in outcome studies.
Cortical excitability in amyotrophic lateral sclerosis: a clue to pathogenesis.
Motor evoked potentials (MEPs) were recorded from selected non-wasted, non-denervated hand muscles in 40 patients with Amyotrophic Lateral Sclerosis (ALS) with both upper and lower motor neuron signs. In most the compound muscle action potential (CMAP) of the target muscle was normal. Compared to the control group, cortical threshold in ALS varied considerably and there was a significant (r2 = 0.702) inverse, exponential, correlation between cortical threshold and MEP/CMAP ratio. There was a linear correlation between threshold and disease duration (r2 = 0.66) so that early in the disease threshold was normal and later the motor cortex could not be stimulated. It is suggested that early in ALS normal threshold reflects glutamate-induced hyper-excitability of the corticomotoneuron. The findings lend support to the hypothesis that ALS is primarily a disease of the corticomotoneuron.
Anti-glutamate therapy in amyotrophic lateral sclerosis: a trial using lamotrigine.
Glutamate excitotoxicity is implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). We report the results of a double blind, placebo controlled, trial using 100 mg of oral daily lamotrigine (3,5-diamino-6-(2,3 dichlorophenyl)-1,2,4-triazine) which inhibits glutamate release. 67 patients were entered and at trial termination of 1.5 years 15 had withdrawn (9 active and 6 placebo) and 12 had died (6 active and 6 placebo). Mean age at entry was 57.5 years for the active and 58.6 years for the placebo groups. Patients were seen at 3 monthly intervals and scored according to neurological deficit based upon age of onset, bulbar and respiratory involvement, ambulation and functional disability. The mean change in clinical scores for the active versus placebo groups over the trial period was 7.1 +/- 3.3 and 9.0 +/- 3.3 respectively (0.05 < p < 0.10). Changes in cortical threshold and MEP/CMAP ratios to magnetic stimulation also did not differ significantly between the two groups. We conclude that lamotrigine in the doses administered does not alter the course of ALS.
Normoglycaemia in dogs after splenic vein reflux of autografted pancreatic microfragments.
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Technique at the basic fault/regression.
This paper is concerned with problems of technique in patients who regress in analysis to a benign or malignant state of regression as conceptualized by Balint in his book, The Basic Fault. The clinical examples of technique in regression given in that book only illustrate states of benign regression and not those of the malignant variety. These examples are examined critically, particularly those advocating the allowance by the analyst of the patient holding his finger or hand, and clinical reasons are advanced to show the disadvantage of this technique in that it can be anti-therapeutic. Aspects of the technique of treating cases of malignant regression are presented and discussed, particularly in terms of the vital importance of maintaining the analytic setting, necessitating the confrontation of the patient in maintaining the analytic boundaries and limits. The need to interpret the intensity and malignancy of the patient's destructive envious attacks on the analyst's capabilities and capacities is essential, as is the need for the analyst not to confuse his healthy aggressive firmness with his sadistic cruelty.
Overnight clonidine suppression test in the diagnosis and exclusion of pheochromocytoma.
In a prospective study designed to differentiate pheochromocytoma from other forms of hypertension, urinary catecholamines were measured after sleep and clonidine administration in 12 patients with pheochromocytoma, 19 hypertensive patients in whom pheochromocytoma was suspected but later excluded, and 31 hypertensive patients in whom pheochromocytoma was never suspected. The test correctly identified all 12 patients in whom pheochromocytoma was present. Four of these had equivocal plasma levels of both norepinephrine and epinephrine, suggesting that overnight clonidine suppression may be of particular value when tumor secretion is intermittent or low. When pheochromocytoma was not present, urinary norepinephrine and epinephrine levels were suppressed below 60 and 20 nmol/mmol creatinine, respectively, after sleep and clonidine, the two in combination giving better suppression than sleep alone. Since urinary catecholamines can be determined relatively easily by high-pressure liquid chromatography with electrochemical detection, this test may be more widely applicable than suppression tests based on plasma measurements.
Overview of randomized trials of postoperative adjuvant radiotherapy in breast cancer.
An overview of the mortality results of the mature trials in which radiotherapy was a randomized option after simple or radical mastectomy is presented. The principal aim of the overview was to study long-term survival, and recent trials, often including chemotherapy options, have not been included. A total of 7941 patients were entered into these trials and 4148 deaths occurred. No differences were found in survival in the first 10 years of follow-up, in trials employing either radical mastectomy or simple mastectomy. Follow-up information after 10 years came mostly from trials employing radical mastectomy with or without irradiation, and in these trials a significant excess of deaths was observed among patients given radiotherapy (P less than 0.001, all trials; P = 0.002, radical mastectomy trials only). Further data collection will be necessary to determine which causes of death are elevated.
Overview of randomized trials comparing radical mastectomy without radiotherapy against simple mastectomy with radiotherapy in breast cancer.
An overview of mortality in the mature randomized trials comparing radical mastectomy without radiotherapy against simple mastectomy with radiotherapy has been conducted. These trials mark a transitional period between radical mastectomy and simple mastectomy as the generally preferred surgical treatment and as such are not strictly trials assessing the value of postoperative adjuvant radiotherapy. All known mature trials have been included and these four trials have entered a total of 3236 patients, in whom 1678 deaths have been recorded. Overall, no significant difference in survival was seen, but there was a nonsignificant trend for patients given radiotherapy to do worse after 15 years of follow-up.
Varieties of transference interpretations: an object-relations view.
The author describes six types of transference interpretations that are looked for from the object-relations viewpoint. In addition, he describes a type of transference interpretation that is better not made, and emphasizes the transference value of silence on the part of the analyst at certain crucial moments in the analysis.
Changes of inner space.
This paper describes the relationship between the experiential aspects of the concept of inner space and of emptiness. This is based on the change of inner experience of a borderline patient during analysis from one of empty space to one of real space. The analysis is described and the relationship of inner space to schizoid and depressive emptiness elaborated, together with the emergence of a healthy inner space (positive emptiness). The components of the capacity to experience inner space from infancy onwards are enumerated and discussed.
Planning a new member entry program for Medicare members.
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Tumour cellularity, oestrogen receptors and prognosis in breast cancer.
One hundred and thirty-seven patients with operable breast cancer have been treated by mastectomy and node sampling. At the time of operation, portions of tumour were taken for determination of oestrogen receptor activity. In 91 cases adjacent tissue was taken for fixation and histological assessment of malignant epithelial cell content ('cellularity index'). The patients were followed for two years or more, or until first recurrence or death. Prognosis (probability of staying disease-free) was significantly better in patients whose tumours contained receptors than in those whose tumours were receptor-negative (p less than 0.03). However, the best prognosis was in patients with low receptor positive tumours. Those with highest values had a prognosis almost as poor as patients with receptor-negative tumours. In addition, a new finding emerged: prognosis was better in patients with tumours of low cellularity than in those with tumours of high cellularity (p less than 0.04). Since, for receptor-positive tumours, receptor level was also significantly correlated with cellularity (R = +0.35, p less than 0.01), the relationship between prognosis and receptor level was re-examined after 'correction' of the latter quantity for differences in cellularity: on this basis, again prognosis was better in patients with receptor-positive tumours (p less than 0.02), but there was no longer a tendency for any one sub-group of patients with receptor-positive tumours to fare better than the rest. It is concluded that prognosis in operable breast cancer is related to oestrogen receptor activity (either per mg weight, or per cell) and to cellularity.
Physical symptoms associated with blood pressure.
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Body type, personality temperament and psychotherapeutic treatment of female adolescents.
In a previous study on emotionally disturbed male adolescents (Stewart, 1980), the subjects were somatotyped in accordance with Sheldon's theory, and the implications of psychotherapeutic treatment were discussed. This is an exploratory study of emotionally disturbed female adolescents in residential treatment at the Anneewakee Treatment Center which seeks to define the population and formulate tentative treatment implications from the results of somatotyping.