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Biomedical subjects

A Tada

Publications and source records attributed to A Tada.

At least 127 records · Page 7Linked to original sources
PubMed1983

Cardiovascular effects of digitalis on intact dogs and isolated cross-perfused atria.

The chronotropic effects of digoxin and deslanoside were studied in canine atria cross-perfused with heparinized arterial blood from donor dogs. Intravenous injections of either drug (100 micrograms/Kg) into the donor dog produced bradycardia followed by ventricular tachyarrhythmia, with or without hypertension, in the donor dog. A significant increase in the developed tension was observed in the isolated atria, with or without slight sinus acceleration. These effects continued over 150 min after the injection. Digoxin (200 micrograms/Kg, i.v.) caused an immediate bradycardia followed by ventricular tachycardia. In addition, ventricular fibrillation occurred in 3 out of 5 donor dogs within 20 min of the drug administration. In isolated atria, there was a marked increase in the developed tension, usually with a little sinus tachycardia. Deslanoside (200 micrograms/Kg, i.v.) caused almost the same response patterns as digoxin. However, this dose of deslanoside caused ventricular fibrillation in all 6 experiments. Drug concentrations in the donor's arterial blood decreased rapidly for 15-20 min and then decreased slowly in all experiments. It is concluded that digoxin and deslanoside have no significant direct accelerating action on the SA node in doses which produced marked increases in the developed tension; only extremely high doses cause a direct, slight sinus acceleration.

Animals↗
PubMed1983

[Cardiac manifestation of the mucopolysaccharidoses: periodical echocardiographic evaluation in six cases].

Serial non-invasive studies including echocardiography were performed for the evaluation and follow-up of the cardiac lesions in six cases with genetic mucopolysaccharidoses. These cases were classified by the enzyme assay into one case of Scheie syndrome, three of Hunter syndrome, one of Sanfilippo syndrome and one of Maroteaux-Lamy syndrome. The echocardiographic examination revealed the most striking change in the mitral valve, which was progressive with increase of the age in most cases. The mitral valve echo was dense and multilayered with a decreased diastolic descent rate (DDR) in the M-mode echocardiogram, and its thick leaflets showed diminished opening on the two-dimensional echocardiogram. The aortic valve echo was also dense in three cases inducing one case with the prolapse of the non-coronary cusp into the left ventricular (LV) cavity. The pulmonary and tricuspid valves showed an unremarkable change, although the echocardiographic signs of pulmonary hypertension was observed in two cases. Diffuse hypertrophy of the interventricular septum and LV posterior wall was observed in five cases and apical hypertrophy was found in a case of Hunter syndrome (Case 2). Parameters of the LV contractility showed almost normal values but the distensibility of the LV posterior wall was impaired in two cases, suggesting stiffness of the cardiac muscle. Although no ischemic change was observed on the electrocardiogram, the echo density of coronary artery wall was not uniform on the two-dimensional echocardiogram and dilated coronary artery was found in two cases. Phonocardiograms disclosed an aortic regurgitant murmur in one case and an apical mitral regurgitant murmur in two cases. In one case of Scheie syndrome, a pansystolic murmur (Levine 3/6) and a mid-diastolic rumble (Levine 2/6) were present at the age of 15 and 16, but after the transient increase in the loudness these disappeared at the age of 18 and only an ejection systolic murmur is audible at the present time, while the mitral valve showed a progressive limitation of the movement on the two-dimensional echocardiogram. Contrary to the reduced DDR and diminished opening of the mitral valve in 3 cases, neither diastolic rumble nor opening snap was recognized in the phonocardiogram. The echocardiographic findings seemed to reflect the patho-anatomical manifestation of this disease, and thus, the periodical echocardiographic evaluation is rewarding to assess the cardiac lesions and their progression in mucopolysaccharidoses.

Adolescent↗
PubMed1982

Monoclonal antibody to acetylcholine receptor: cell line established from thymus of patient with Myasthenia gravis.

A human B cell line producing a monoclonal antibody to an antigenic determinant of acetylcholine receptors was established by cloning B cells that had been transformed in vitro by Epstein-Barr virus. The B cells were obtained from the thymus of a patient with myasthenia gravis. The antibody produced by the cell line precipitated acetylcholine receptors from denervated and innervated rat muscle and from human muscle, but did not show detectable response to the acetylcholine receptors from the electric organs of Narke japonica. The monoclonal antibody showed identical binding patterns in innervated and denervated rat muscles. Passive transfer of the monoclonal antibody into rats induced moderate muscle weakness and electromyographic changes characteristic of myasthenia gravis.

Animals↗
PubMed1981

Delta waves in the EEGs of patients with intracerebral hemorrhage.

Localized polymorphic delta wave activity appears ipsilaterally in patients with intracerebral hematoma without a shift of midline structures, regardless of the location of hematoma. Appearance of delta wave slowing after thalamic bleeding is quite variable, however, and may produce localized slowing or unilateral diffuse polymorphic delta wave activity. Unilateral diffuse polymorphic delta wave activity is seen in patients with larger hematomas of 30 mL or more, which cause a shift of the midline structures. The shift of midline structures, including the hypothalamus and surrounding structures, is thought to be one of the main factors responsible for the production of unilateral responsible for the production of unilateral diffuse polymorphic delta wave slowing.

Brain Diseases↗