Nagoya Journal of Medical Science

1) The different modes of assisted or controlled circulation have been considered for an intractable cardiac failure. The authors advocated the following classification that may be useful for the hemodynamic study of assisted circulation.
A) The partial bypass technique:
(1) veno-arteiral pumping,
(2) right ventricular partial bypass,
(3) left ventricular partial bypass, and
(4) partial cardiopulmonary bypass.
B) The total bypass technique:
(1) right ventricular total bypass,
(2) left ventricular total bypass,
(3) synchronized arterial counterpulsation, and
(4) total cardiopulmonary bypass.
2) Indication for various types of assisted circulation were discussed on the basis of the clinical and experimental experiences.
3) The authors proposed the concept of an optimal flow rate of assisted circulation employing partial bypass technique. The maximum efficacy of assisted circulation may be obtained by perfusing at the optimal flow rate, while the serious com- plications caused by perfusing at an unnecessarily high flow rate are avoided.

Fatty acid peroxides have been found in the atherosclerotic human aorta by Glavind. A correlation exists between the extent of the atherosclerotic changes and the content of lipid peroxides. It may be inferred that the presence of peroxides in the aorta brings about a disturbance in the function of the arterial wall and gives rise to atherosclerotic changes.
Vitamin E, which prevents the peroxidation of lipids, might suppress the atherogenesis. X-ray irradiation, which induces the auto-oxidation of lipids, might promote the process of the atherogenesis. From these considerations, the present investigation was performed. The determinations of peroxides were carried out on the rabbit aorta by the ammonium thiocyanate method. A correlation existed between the extent of the atherosclerotic changes and the content of lipid peroxides. The aortas with no atherosclerotic changes contained only small amount of peroxides. Peroxides of the rabbit aorta were determined by the method of TEA. Vitamin E injection prevented the lipid peroxidation in the aortas and livers. Furthermore, Vitamin E suppressed the atherosclerotic changes. Peroxides were produced by X-ray irradiation in the aortic wall and liver of the rabbit. Whole body X-ray irradiation promoted the progress of atherosclerotic changes in cholesterol fed rabbit, and produced atheroma-like plaque in the thoracic aorta of the rabbit.
The respiration of the aorta of rat was decreased by peroxides added in the diet. However, the respiration of liver was not influenced. The activity of cytochrome oxidase was more inhibited than that of succinic dehydrogenase. In vitro effect of peroxides on the respiration of the aorta of rats was also observed.

Young guinea pigs fed a choline deficient diet were employed for light and electron microscopic studies. They showed severe growth retardation, muscular weakness, diarrhea and subcutaneous hemorrhage. About 73% of the deaths occurred within 5 weeks and survival time varied from 8 to 305 days. The symptoms of animals died within 5 weeks were more acute than the remainders. The gross appearance of the dead animals was characterized by marked emaciation, disappearance of the adipose tissue and congestion of the liver. Fat deposition in the liver was found microscopically in 17 of 48 animals. The light microscopic examination revealed definite degenerative changes of the liver cells including vacuolation, swelling and necrosis, and these findings became prominent with the duration of choline deficiency. In the electron microscopic examination the most conspicuous changes occurred in mitochondria of the liver cell. Mitochondria decreased in number gradually as choline deficiency progressed and manifested some characteristic features at each period of the experiment. Two types of mitochondrial swelling could be observed, the first type was recognized at the early stage and the second type developed at the terminal stage after the 1Oth week of choline deficiency. In the first type, mitochondria became balloonlike but there was no essential destruction of its fundamental membranous structures. In the second type, mitochondria became gigantic and membranous structures were more or less distracted. Occasionally there found protrusion of mitochondria, dissolution of mitochondrial membrane, disarrangemenet of cristae and appearance of small vesicles in mitochondrial matrix at the terminal stage of choline deficiency. On the other hand, the animals of the recovery experiment showed notable improvements on the above-mentioned symptoms and changes of the liver.