Exercise stress myocardial perfusion scintigraphy with thallium-201

We performed exercise stress scintigraphy with thallium-201 in 88 patients including 31 patients of effort angina and nine patients of old myocardial infarction without angina. Sensitivity of exercise stress scintigraphy to detect effort angina was 77%, whereas sensitivity of exercise stress ECG was only 44.5%. The combination of stress scintigraphy with stress ECG enhanced sensitivity up to 87%. Exercise stress scintigraphy was useful particularly in cases with one vessel disease and those who failed to achieve sufficient exercise stress. Besides exercise stress scintigraphy did not show false positive response, differing from exercise stress ECG. Myocardial imaging is a method which shows the balance between myocardial perfusion demand and supply.

Noninvasive cardiovascular findings in familial amyloid polyneuropathy

The cardiovascular system was examined in 19 cases of familial amyloid polyneuropathy. In a group of patients with neurological involvement, various cardiac abnormalities were common, including orthostatic hypotension, prominent apex cardiographic A waves, abnormal apical systolic waves (bulges), systolic murmurs, mid-systolic clicks, QS waves, atrioventricular block, left bundlebranch block, and abnormalities of ejection time and pre-ejection period. Though there was one case with pronounced cardiac abnormality despite a normal neurological state, and though cardiovascular symptoms appeared later than neurological symptoms, the degree of cardiac involvement generally paralleled the severity of the neurological disorder.

The use of non-aqueous chloroform/methanol extraction for the delipidation of brain with minimal loss of enzyme activities

When freeze-dried brain was extracted at -4-0degrees C with dry chloroform/methanol (2:1 v/v), four of the five enzymes examined were recovered in the diethyl ether-washed residue without inactivation. By contrast, extraction with chloroform/methanol (2:1 v/v) in the presence of water destroyed activities of all the enzymes examined. The amounts of major lipids extracted were similar whether extraction was done in the absence or presence of water. The study was carried out with special interest in 2':3'-cyclic nucleotide 3'-phosphodiesterase (EC 3.1.4.37), which is firmly bound to the membrane structures of brain white matter.

Familial progressive bulbar-spinal muscular atrophy: case report with muscle biopsy study

A case of familial progressive bulbar and spinal muscular atrophy was presented. The patient was a 59-year-old male with chief complaints of gait disturbance and nasal voice. His illness started at the age of 39 and very slowly progressed over 20 years. The clinical symptoms and signs were characterized by muscle weakness and atrophy due to lower motor neuron disease in the brain stem below the lower pons and the spinal cord. The electromyograms and muscle biopsy findings are basically neurogenic. In spite of the bulbar signs, the course of the disease is extremely slow. The diagnostic criteria was proposed after reviewing eight other cases reported in the literature.

Electron microscopic studies of the T-system--the effects of hyperosmolar glycerol and dantrolene sodium on mammalian muscles

Electron microscopic studies of the T-systems in mammalian muscles were performed to investigate the effects of hyperosmolar glycerol solution and dantrolene sodium. The results indicate that in mammalian muscles the terminal cisterns of the sarcoplasmic reticulum seem to be the site of morphological changes which occur when the muscle specimens were transferred from the hypertonic glycerol solution to isotonic washing solution. When the muscle specimen was further exposed to dantrolene solution, the above changes were intensified. The changes of the terminal cisterns of SR were characterized by prominent vacuolar changes and the T-tubules were pressed and narrowed by those vacuoles secondarily. The glycerol and dantrolene technique did not cause any electron microscopic changes in the sarcolemma, myofibrils, nor Z-discs, and selective changes in the T-system, i.e. at the terminal cisterns of SR were demonstrated. This technique, excitation-contraction uncoupling, abolishes isometric twitch tension up to 99.7% and serves for the purpose of prolonged intracellular recordings of mammalian muscles without movement induced artifacts.

The mechanism of neuromuscular fatigue. A study of mammalian muscle using excitation-contraction uncoupling

Neuromuscular transmission failure was measured during rapid repetitive stimulation of the rat hemidiaphragm in vitro after excitation-contraction uncoupling by hyperosmolar glycerol, washing, and dantrolene sodium. Observations of resting membrane, miniature endplate, action, and endplate potentials (epps) showed that neuromuscular transmission failure occurred during stimulation because of a decrement of the epp. This decrement was due both to a reduced number of quanta released and to a variable reduction of quantal size. The time course of these events was studied, and limited observations were made on recovery. Observations of the difference between the epp decrement of cut muscle and of partially curarized muscle suggest a prejunctional action of curare.

Excitation-contraction uncoupling. The effect of hyperosomolar glycerol solution and antrolene sodium on mammalian muscle in vitro

In the rat hemidiaphragm, in vitro dantrolene sodium irreversibly reduced twitch tension up to 20% of the original value in 20 minutes of exposure. The phenomenon was dose related. Dantrolene sodium did not affect (1) resting membrane potential (IMP); (2) miniature endplate potential frequency of amplitude; or (3) endplate potential amplitude decrement of repetitively stimulated partially curarized muscle. A combination of hyperosmolar solutions of glycerol and dantrolene sodium abolished contraction of mammalian muscle with no demonstrable effect on neuromuscular transmission or muscle fiber RMP. With this technique, prolonged recording from repetitively activated muscle fibers is possible.