Biomedical subjects
Publications and source records attributed to R Simon.
If mediastinal lymph-node calcifications are frequent, the "hodgkinian" origin of these calcified adenopathies is unusual; less than 30 cases are reported in the literature. A new observation is described here. These lymph-node calcifications occur most often after radiotherapy; exceptionally "hodgkinian" adenopathies can appear ready-calcified.
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Slow (m.soleus) and fast (m.tibialis anterior) muscles of the rabbit were subjected to indirect long-term intermittent stimulation (3 weeks, 8 hrs daily) with a frequency pattern of 10 imp/sec. Whereas no changes were observed in case of the slow muscle, stimulation induced profound changes in the fast tibialis anterior muscle. These consisted in a rearrangement of the enzyme activity pattern of energy-supplying metabolism, e.g. decrease in glycogenolytic and glycolytic enzyme activities and severalfold increase in key enzymes of aerobic endoxidation of substrates in beta-oxidation and the citric acid cycle. Concomitant with the increase in aerobic oxidative capacity, there was an increased resistance to fatigue. Histochemical studies revealed a strong increase in mitochondria of all fibres. The bimodal distribution of fibre cross-sectional area in the normal tibialis anterior muscle was changed by stimulation into a more homogeneous population of fibres with a smaller cross-sectional area. Despite a 50% increase in time to peak of isometric twitch contraction no changes were observed in the fibre population with regard to myofibrillar ATPase reaction in quantitative evaluation of whole cross-sections of the muscles. The percentage of fibres histochemically classified as slow amounted to 2.8% and 3.1% in control and stimulated tibialis anterior muscle. Nevertheless the data suggest a transformation of the fibre population under the influence of long-term intermittent stimulation.
Twenty-three patients with the midsystolic click - late systolic murmur syndrome were investigated by right and left heart catheterization, cineangiography and echocardiography. Most had symptoms such as atypical chest pain and arrhythmias. Except in one patient, slight to moderate mitral incompetence was present at rest (20 patients) or during stress testing by the infusion of aramine or rapid atrial pacing (2 patients). In all cases, an abnormal systolic mitral valve motion was found by left ventricular cineangiography. In 14 of 15 technically satisfactory echocardiograms a systolic prolapse of one or both mitral leaflets was observed. A minority of the patients had localized abnormal wall motion in the posterobasal area or moderate generalized hypokinesis.
A new indicator quantity principle is presented which permits estimation of the regurgitant fraction in mitral incompetence from left heart angiocardiography by videodensitometric measurement of contrast medium content in the left heart chambers. In 90 experiments on dogs, a linear correlation of r = 0.89 was established between simultaneous determinations of mitral regurgitation by videodensitometry and electromagnetic flow measurement. Since only 1 catheter is needed for the injection of contrast medium and concomitant aortic incompetence can be computed from the same videodensitograms, this method is considered to be of special interest in clinical heart catheterization.
The severity of aortic incompetence can be assessed by quantifying the alteration of blood flow in the common carotid artery. The use of a pulsed multichannel ultrasonic Doppler device in 41 patients with aortic valve disease yielded a satisfactory correlation between the ultrasonic parameters and the maximal aortic regurgitation distance. Correlations between Doppler parameters and regurgitation (thermodilution) were less strict.
Twenty-three patients with the syndrome of midsystolic click--late systolic murmur were investigated by right and left heart catheterization, cineangiography and echocardiography. Most of the patients had symptoms such as atypical chest pain and arrhythmias. Except in one patient, slight to moderate mitral incompetence was found at rest or during stress testing by infusion of aramine or rapid atrial pacing (2 patients). In all cases, an abnormal systolic mitral valve motion was found in left ventricular cineangiography. In 14 of 15 technically satisfactory echocardiograms a systolic prolapse of one or both mitral leaflets was observed. A minority of the patients had localized abnormal wall motion in the postero-basal area or moderate generalized hypokinesis.
Long-term second remissions were seen in 5/66 patients with all. Relapse was extramedullary in 2/5. Persistent, progressive marrow lymphocytosis preceded relapse in 4/5 patients and persistent marrow eosinophilia in 1/5. All 5 patients had had an unmaintained remission of at least 6 months prior to relapse, and responded the second time to drugs which were essentially the same as those used initially. We conclude that long-term second remissions may occur in all. Patients who relapse after 6 months or more of unmaintained remission should be treated with the drugs used in current initial induction regimens in hope of cure.
A staging scheme for hepatocellular carcinoma was presented at an International Symposium on Liver Cancer in Kampala, Uganda in 1971. Historical, clinical, and laboratory aspects of that staging scheme were examined for prognostic significance in 72 untreated patients with this disease studied at the Uganda Cancer Institute. The median survival for the entire group was 1 month. The presence of a serum bilirubin concentration of greater than 2 mg/100 ml or weight loss greater than 25 percent of body weight were the poorest prognostic features. Other factors with prognostic significance were visible abdominal collateral circulation, ascites, tumor differentiation, and serum levels of alkaline phosphatase, SGOT, alpha fetoprotein, and proline hydroxylase. A modified staging scheme is presented which defines three prognostically different groups of Ugandan patients. It is hoped this staging scheme will serve as a stimulus for analysis of similar prognostic features in other populations of patients with hepatocellular carcinoma.
In a cross-national comparison of the frequency of occurrence of various diagnoses among elderly psychiatric patients admitted to public mental hospitals in London and New York, a short battery of psychological tests was administered to all patients independently of psychiatric examination. The psychological assessment was focused on the differentiation between dementing and affective disorders. The test performance showed a highly significant difference between the two groups as diagnosed, and when patients were allocated to groups on the basis of tests alone these allocations showed a high rate of agreement with initial psychiatric diagnosis. There was a similar high rate of agreement between test allocation and hospital diagnosis in the U.K., but this was not so in the U.S. No significant differences were found between the test performance of U.K. and U.S. patients, except on the WAIS Vocabulary and the Angles Error measurement of the Bender-Gestalt test. When the effects of age and Vocabulary score were eliminated these differences disappeared. The hypothesis that the diagnosis of affective disorder would be confirmed by a relatively greater improvement in test performance over time in this group of patients was not upheld by the non-parametric analysis of change scores. However, an analysis of covariance utilizing age and initial score did indicate the expected differential improvement.
We measured serum lactate dehydrogenase levels in 36 patients with localized Ewing's sarcoma before treatment. The results were evaluated to determine if the levels served as a prognostic indicator for metastatic spread. After adjusting for primary site of disease and adjuvant chemotherapy, the pretreatment serum lactate dehydrogenase proved an extremely good predictor of which patients would ultimately develop metastatic disease. The median serum lactate dehydrogenase of the total group was between 201 and 214 IU/litre. Three of 18 patients presenting with serum levels of this enzyme of less than or equal to 201 IU/litre ultimately developed metastases, while 16 of 18 patients who presented with serum levels of greater than or equal to 214 IU/litre developed metastases (P less than 0.001).
In controlled clinical trials there are usually several prognostic factors known or thought to influence the patient's ability to respond to treatment. Therefore, the method of sequential treatment assignment needs to be designed so that treatment balance is simultaneously achieved across all such patients factor. Traditional methods of restricted randomization such as "permuted blocks within strata" prove inadequate once the number of strata, or combinations of factor levels, approaches the sample size. A new general procedure for treatment assignment is described which concentrates on minimizing imbalance in the distributions of treatment numbers within the levels of each individual prognostic factor. The improved treatment balance obtained by this approach is explored using simulation for a simple model of a clinical trial. Further discussion centers on the selection, predictability and practicability of such a procedure.
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Patients in remission with advanced acute lymphatic leukemia were randomly assigned to receive chemotherapy alone or chemotherapy plus immunotherapy with a Burkitt lymphoma tissue culture cell line (RAJI). Remission duration in both groups were identical. Complement-dependent cytotoxic antibody was seen in 5 of 8 immunized patients and 0 of 8 controls. This antibody reacted with RAJI and both allogeneic and autologous acute leukemia cells. Antibody titers began to rise after 2 months, peaked at 4 months, and then declined prior to relapse in all patients. The time course of the increase in mixed-leukocyte culture response to RAJI was similar to immunized patients. An increased in vitro response to phytohemagglutinin was seen during drug administration in all patients. Although no clinical benefit was seen in this small number of patients with the RAJI injections, these in vitro responses are encouraging and new immunization schedules will be investigated.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.