The sizes of the great arteries in patients with ventricular septal defect were studied and their correlations with hemodynamic data and surgical results were discussed.
Intimate correlations could be found between pulmonary-to-systemic systolic pressure ratio and cross sectional area of the pulmonary artery or aorta-to-pulmonary artery diameter ratio.
The ascending aorta was found absolutely hypoplastic in some cases with hyperkinetic pulmonary hypertension. In patients with increased pulmonary vascular resistance, the ascending aorta was not so hypoplastic as in hyperkinetic group.
As patients with the hypoplastic aorta frequently showed fatal low cardiac output syndrome in the early postoperative period, such cases should be excluded from candidates for open heart surgery by preoperative angiocardiographic examination.

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Lungs of patients in cases of mitral insufficiency were studied to observe the influences of cardiopulmonary bypass. In addition to preoperative pathological conditions of lungs, more marked changes were noted in the type II alveolar epithelial cells and the interstitium postoperatively.Dilatation of capillaries and interstitial edema became evident. Concomitantly, a decreased number of granules containing lamellar structures, enlargement and fusion of these granules, and invasions of swollen and coarse lamellar structures to a granule forming a bulky conglomeration were notable. Other changes demonstrated in the cytoplasmic matrix were an increase of electron density and a dilatations of granular endoplasmic reticulum.
No definite conclusion was drawn from the present investigations alone, however, structural alterations described in the paper are suggestive of resulting changes of lung surfactant, which will be a cause of pulmonary syndrome because of poor ability to keep the alveoli open.

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Long term effects of chondroitin sulfates A and C on the lipid and hexosamine levels were studied for 22 weeks in the patients with atherosclerosis. Chondroitin sulfates A and C both kept serum cholesterol levels low in the patients in comparison with the controls during the course of treatment.
Short term effects of chondroitin sulfate C injected intravenously on the thrombus formation time were also studied in the patients by Chandler's method in connection with thrombogenic causes of atherosclerosis. The prolongation of thrombus formation time was observed at 30 and 60min. after the injection of the substance.

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(1) The vascular permeability factor is present in the renal cortex.This factor has no pressor activity and is quite different from renin.
(2) The vascular permeability factor has the characteristics of a protein. Immunoelectrophoretic study reveals a single precipitation line.
(3) Administration of the vascular permeability factor to mice causes cerebral hemorrhage.
(4) Rabbits subjected to renal ischemia develop cerebral hemorrhages but are provided protection against it through lanolin feeding.
(5) Some evidence is presented indicating that the renal vascular permeability factor plays an important role in the development of vascular lesions.

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An attempt was made to investigate experimentally whether arteriolosclerosis in the myocardium was accelerated by concomitant arterial hypertension and/or hypercholesterolemia.
Young male albino rabbits were divided into 5 groups, i.e., hypertensive, hypertensive and hypercholesterolemic, normotensive and hypercholesterolemic, operated but normotensive and control group, respectively.
Hypertension was induced by means of a modified Goldblatt's technique and hypercholesterolemia by feeding lanolin and cotton seed oil. To obtain the media/diameter ratio of small arteries and arterioles in the myocardium, the constricted and deformed vessels were stretched completely and the widths of the media and external diameter of corrected vessels were calculated geometrically. The frequency of the small vessels having the intimal changes was compared in each group.
The media/diameter ratios of small arteries and arterioles in the myocardium increased in the groups with hypertension and were not influenced by hypercholesterolemia. The media/diameter ratios in each rabbit declined linearly in 40 to 110μ. of external diameter and did not show a specific increase. Endothelial hyperplasia and splitting and proliferation of the internal elastic lamina were the main intimal changes of the small myocardial arteries and arterioles in the rabbits which were not fed with lanolin and cotton seed oil. These intimal changes were found most frequently in the subendocardial regions of the left ventricles of hypertensive rabbits.
It was suggested that the medial changes of arterioles and small arteries in the myocardium were related to hypertension and the intimal changes were accelerated by hypertension but might not he primarily caused by hypertension.

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The immediate mechanical effect of changes in peripheral resistance of a local flow region on systemic arterial pressure was theoretically studied. Assuming proportionality between pressure and flow and constancy of cardiac output, the following theoretical relationship was derived : b=ad/(1+a-ad), where b=rate of change in arterial pressure, a=rate of change in peripheral resistance of the particular region and d=initial ratio of the local flow to cardiac output. Using this formula, effects of superior mesen-teric flow fluctuation and rhythmic splenic contraction on arterial pressure were analyzed.

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The plasma and kidney angiotensinases were compared in the rat. Effects of acid and alkali treatments and of enzyme inhibitors on the angiotensinase activities and the renin-angiotensionogen reaction were studied. Angiotensinase activity of the plasma was greatest near neutral pH at 37°C and was blocked almost completely by dialysis against disodium ethylenediaminetetraacetic acid (EDTA). The kidney angiotensinase at neutral pH was also inactivated by acidification and dialysis against EDTA. The activity having a optimum pH of 4.5 to 5.0 was not affected by the dialysis but was inhibited by alkali or diisopropyl fluorophosphate. The renin-angiotensinogen reaction was least affected by incubation of the acid-treated and dialysed kidney extract with the dialysed plasma at pH 7.4 and 37°C.

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An instance of digitalis-induced double atrioventricular nodal rhythm associated with ventricular electrical alternans has been described. To the knowledge of the author, it is the first such combination reported. One atrioventricular nodal pacemaker (group A) produces non-paroxysmal atrioventricular nodal tachycardia and the other pacemaker (group B) produces atrioventricular escape rhythm with electrical alternans. The influence of digitalis and hypokalemia in relation to such cardiac arrhythmia has been discussed. The necessity of early recognition of digitalis intoxication in elderly patients who develop non-paroxysmal atrioventricular nodal tachycardia and atrioventricular nodal escape rhythm during digitalization has been emphasized. The appearance of electrical alternans in this case is thought to be related to digitalis intoxication.

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A 70-year-old man with partial hypoplasia of the left ventricle, rudimentary right coronary artery and partially fused kidneys was presented. The case had normal blood pressure and left axis deviation in electrocardiogram and died of cerebral thrombosis and pneumonia. Autopsy revealed a localized hypoplasia of myocardium at the anterior wall of left ventricle, rudimentary right coronary artery, thin-walled dilated circumflex coronary artery, thin-walled aorta and a butterfly-shaped fused kidney with another small accessory kidney at its left uppe pole.
Comparison was made with the single coronary artery and the hypoplasia of the aortic tract complexes from the view points of morphology and associated anomalies and a possibility of adult conversion of hypoplasia of the aortic tract complex was suggested. An explanation for the left axis deviation was also given.

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