Nagoya Journal of Medical Science

Experiments were performed in 48 dogs subjected to a shock produced by hemorrhage after the modified Wiggers' method. Dogs were infused 90 minutes after hemorrhage with one of six test substances; shed blood, 5% glucose solution, or four kinds of dextran (mw. 75,000, 47,000, 29,000 and 12,000). Infusion of dextran with mw. 29,000 produced the most remarkable increase in femoral arterial blood flow above the prehemorrhagic level. This flow improvement was thought to be more attributable to reduction in blood viscosity than an increase in blood volume.

Some histological and histochemical findings on the allergic experimental myositis of guinea pig and human cases with neuromuscular diseases were reported.
Innoculated animals showed hardly any clinical sings but histological changes of thigh muscle and diaphragma which were similar to those seen in human polymyositis. Diaphragma showed more remarkable changes than thigh muscle.
In human polymyositis, the increase of endo-, epi-, and peri-mysial connective tissue, round cell infiltration into interstitial tissue, phagocytosis with regenerating fibre and necrosis of muscle fibre were dominant findings.
Regarding histochemical findings, muscles from experimental animals showed reduction of phosphorylase activity, elevation of succinic dehydrogenase in early stage, slight reduction in late stage, and elevation of alkaline phosphatase in capillary elements.
In human polymyositis, specimen of muscle showed mildely reduced phosphorylase activity and little change of succinic dehydrogenase activity and in neuromuscular disease, succinic dehydrogenase activity was markedly reduced and phosphorylase activity was well retained.
Finally, SGOT values in experimental animals were elevated on early stage then gradually reduced and SGPT values varied from case to case though the values throughout the course were higher than normal ones.

An experimental study of rats on the fibrillation potential of denervation and the spontaneous electrical activity of normal muscle was carried out chiefly to find their differential key points.
As the results, fibrillation potentials in denervated muscle on the 21st day after denervation were recognized to be spike potentials with the initial positive phase. But this prescription had to allow the condition that fibrillation potentials would be found only infrequently in normal muscle at rest, so quantitative con- sideration that these potentials should be found at least in more than two points of a muscle was taken in order to be regarded as a sign of denervation.
In normal muscle, four types of spontaneous electrical activities were recognized clearly. The first type was the irregularity of the base line which was suggestive of negative monophasic activity, and provisionally named the end plate noise according to Buchthal's opinion. The second type was a spike potential with a prominent initial negative phase and called nerve potential according to Jones and supposed to be regarded not as a type of fibrillation potentials but as a normal sign. These two potentials were inferred to be dual under present conditions. The third type was fibrillation potential and the fourth type was so-called myotonic activity. The other activity was seldom found in normal muscle.

The effects of hyperbaric oxygenation were investigated in 46 dogs with myocardial infarction produced by injecting microspheres of 40 µ in diameter.
1) Hyperbaric oxygenation did not prevent early death from ventricular fibrillation. However, it afforded protection against late death.
2) The hemodynamic deterioration of myocardial infarction was prevented by hyperbaric condition.
3) Ventricular tachycardia and ventricular ectopic beats occurred more frequently in hyperbaric condition than in room air.
4) The deviation of the ST segment was reduced by hyperbaric oxygenation.
5) SGOT and SGPT were not significantly reduced by hyperbaric oxygenation.
6) The extent of the infarcted lesion was significantly less in the caisson group than in the control group. Histological findings at the margin of the lesion showed further regenerative improvement in the caisson group.
7) Microangiographic studies showed that revascularization was developed more progressively in the caisson group.
The results suggested the protective effect of hyperbaric oxygenation on the ischemic process after myocardial infarction.
With the present study, it would be concluded that hyperbaric oxygenation exerts a beneficial effect on myocardial infarction.

Cerebral edema must be closely implicated in the cerebrospinal fluid production rate and corticosteroid, which is effective to reduce cerebral edema, must have influence upon the rates of the cerebrospinal fluid production in the edematous brain. There has been a little of previous studies which dealt with the influence of corticosteroid upon the cerebrospinal fluid production rate, but little of reports of studies of the changes of the cerebrospinal fluid production rate in the edematous brain as yet. In this series of experiments the change of the cerebrospinal fluid production rate in the experimentally induced edematous brain and the influence of dexamethasone upon it were studied in dogs by means of ventriculo-cisternal perfusion technique. The dog with his head shaken by the newly designed machine was anesthetized and the lateral ventricle and the cisterna magna were punctured 24 hours after shaking. The artificial cerebrospinal fluid containing of inulin as a tracer was pumped into the lateral ventricle of two groups of dogs with and without intravenously administered dexamethasone, and droplets out of the cisterna magna were sampled. Results by this experiment were the reduction of the cerebrospinal fluid production rate in the edematous brain and the further reduction of it in the edematous brain after the dexamethasone administration. This suggests that dexamethasone may act closely on water-ion transpot in the cerebrospinal fluid secretion system.

Utilizing the ¹³¹I-MAA (macroaggregated albumin labeled with iodine-131) scintillation scanning method, regional pulmonary blood flow distribution was studied in 47 cardiac patients with pulmonary hypertension.
Remarkable increase of blood flow in the upper zones of the lung together with decrease in the lower zones was found in the majority of the patients with mitral valve disease, while in the congenital heart disease with left to right shunt group, elevation of upper/lower ratio of pulmonary blood flow was minimal even in the patients with severe pulmonary hypertension. Upper/lower ratio of pulmo- nary blood flow showed a good correlation with left atrial pressure and mean pulmonary circulation time but not with pulmonary arterial pressure.
The mechanism underlying these differences of pulmonary circulation pattern in various heart diseases with pulmonary hypertension was discussed and the role of primary factors (perivascular edema and vasoconstriction) was emphasized as the cause of this reversed pattern of pulmonary circulation.
Postoperative studies on the 16 patients with mitral valve disease proved that this abnormal distribution of pulmonary blood flow could be improved in a com- paratively short time by successful surgical correction of the disease, whereas in those patients with upper/lower blood flow ratio in an erect position over 2.0, high operative mortality resulted. The surgical significance of the upper/lower pulmonary blood flow ratio measurment in determining the operative risk and curability of the disease was also discussed.

Studies were carried out to devise a new multilayer membrane artifiilal lung. It was determined from the present studies on flow patterns and dye clearance that the basic design of the multilayer membrane artificial lung should have one-inlet and one-outlet and be elliptic in shape. Many little projections were made on both surfaces of a distributing mat in order to support membranes and to give turbulences to the flowing blood. Distance between two membranes or the thickness of the blood layer was determined to be 0.8-0.9 mm. Fifty Hs silicon rubber was used as material for the distributing mats in order to prevent blood leakage from between the membranes.
Silicon rubber membrane and Teflon membrane were investigated for gas permeability by using a model of the elliptic artificial lung and a model of the Peirce-Galletti's artificial lung. Nineteen mongrel dogs were subjected to the studies. Phycon membrane or silicon rubber membrane, made in Japan, showed an excellent gas exchange capability and proved to be the best membrane now available.
One unit of the artificial lung comprises two mats and two membranes, having an oxygenating surface area of 1540 cm2• This elliptic membrane artificial lung with a stack of ten oxygenating units has approximately 60 ml/min of oxygen uptake when Phycon membrane is used, and can be applied to total cardio- pulmonary bypass for infants and small children.

The adult male monkeys (macaca fuscata fuscata) were used in this study. After ecological behavioral observations on three selected pairs, bilateral temporal lobes of the dominant monkeys were removed and submissive ones were operated with only exploratory craniotomy for the control study. Subsequently, the behavioral changes were observed individually and in the each same pair. Individual behavioral changes of the bilateral temporal lobectomized monkeys were those of the Klüver-Bucy's syndrome. Changes in pair suggested the "socioagnostic" behavior.
Selected one of the operated dominant monkeys with persistent Klüver-Bucy's syndrome, psychometric examinations mediated visually, were performed to elucidate the mechanism of the agnostic behaviors which were observed ecologically, which was the main purpose of this study. The various visual discriminations (of color, form, size and brightness) were tasked on the bilateral temporal lobectomized monkey under proper conditionings with comparison to the sham· operated monkey as the control monkey. Eventually, the bilateral temporal lobectomized monkey could not learn the tasks after even 200 trials each, while the control monkey was able to reach to the criterion (20 consecutive correct responses) finally. The essential factor of the agnostic behaviors seem to be settled on the dissociation of the limbic function from the visual function.

In order to take an axial transverse tomogram having few obstructive shadows, the phantom and human experiment were perfomed and studied.
Thorax cage phantom composed of ribs made of lead wire was laid on the table of axial transverse tomograph of horizontal type and the axial trans- verse tomograms were taken with the central X-ray of caudalocranial or crania- caudal direction with the range of rotation of 180°, rotating from the right, front and left side of the body.
Obstructive shadow arose mostly when projected caudalocranial direction of central X-ray, while fairly few when taken with craniocaudal direction.
With exposure of full rotation of 360°, the obstructive shadow was more faint than the above two.
This was confirmed also with the human experiment.