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Biomedical subjects

J Vasků

Publications and source records attributed to J Vasků.

At least 55 records · Page 3Linked to original sources
PubMed1983

A comparative study of a group of eight calves, surviving longer than 1 month with the total artificial heart.

Over the last 2 1/2 years, eight calves with implanted total artificial hearts (from experimental group IV) have survived for greater than 1 month. In this group two subgroups were further differentiated, subgroup IVa, including three calves surviving 31, 35, and 75 days, and subgroup IVb, with five calves surviving 104, 142, 150, and 155 days and one calf still surviving greater than 160 days. Mean survival in the fourth group was greater than 106.5 days. The artificial ventricles used were the TNS-BRNO-II made of polymethylmethacrylate (seven calves) and the TNS-BRNO-III, made of segmented polyetherurethane (one calf). The controller and driving units were of our own design. The Chirasist-TN-3 and TN-4 worked without trouble over the total duration of the studies in all calves. Autoregulation of suction was used in three of these calves. All calves survived in good physiological condition; however, some common changes were observed in all of them, such as a gradual central venous pressure increase and liver enlargement. Anticoagulation therapy was used in all calves. Causes of death were technical in three cases and biological in four. Body weight gains were normal in the majority of these calves, with slight individual differences observed. Diaphragm mineralization of various degrees was observed in three cases. In one of them it was directly related to the cause of death. These results are very encouraging for further development of the total artificial heart research in our center.

Animals↗
PubMed1980

BRNO-I, an implantable, diaphragm-type total artificial heart: technical aspects of design.

The technical aspects of artificialheart design for experiments on calves are presented in this paper. The object of the design was to verify the basic anatomic and hemodynamic criteria for the design of more perfect cardiac prostheses. Each of the ventricles has a 100-ml stroke volume and is dismountable. Rigid parts are made of polymethylmethacrylate. The inlet valve has the shape of a flap. The outlet valve has two polyurethane reinforcing leaves. The diaphragm is also made of polyurethane. During tests using artificial circulation, a maximum cardiac output of 14.6 L/min was achieved. Typical sensitivity of flow on the atrial pressure is 0.3 L/min/torr at a frequency of 90 pulses per minute.

Animals↗
PubMed1979

Determination of cardiac output of the artificial heart from the drive air flow.

An indication chamber, inserted between the right heart drive and the pump proper, was designed to provide continual measurement of the quantity of blood pumped by the pneumatic artificial heart. The flow is evaluated from the motion of a piston provided with a photoelectric transducer. The effect of compressibility of the drive gas on measurement accuracy is eliminated. The indication chamber provides for automatic replenishment of gas that escapes by diffusion and through minor leakage. During testing in an artificial circulation within the range of physiological conditions, measurement in accuracies did not exceed 5%.

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PubMed1979

The effect of preirradiation application of aspartic acid salts on hemopoietic recovery in X-irradiated mice.

The possibility of radioprotective action of K and Mg aspartate administered in tap water for ten days prior to X-irradiation was investigated in male mice of the strain C 57 Bl/10. In normal animals, thymus weight was found to be increased by 10-day treatment with K and Mg aspartate. The postirradiation regeneration of spleen weight and incorporation of radioactive iron into the spleen and femoral marrow following sublethal irradiation was favorably modified by the treatment used. Pretreatment of mice with K and Mg aspartate delays the onset of early deaths at irradiation with an absolutely lethal X-ray exposure and raises the percentage of surviving animals after nearly lethal exposures.

Animals↗
PubMed1979

The effect of postirradiation application of aspartic acid salts on hemopoietic recovery in sublethally X-irradiated mice.

The effect of aspartic acid salts, especially of K and Mg aspartates, on certain hematological changes in the peripheral blood and hemopoietic organs of sublethally X-irradiated male mice of the strain C57Bl/10 was investigated. Salts of aspartic acid were administered in tap water after irradiation. A favorable effect of aspartic acid salts on erythropoietic recovery and on regeneration of thymus weight was found during the first two weeks after irradiation.

Animals↗