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In a close parallel to the developmental pattern of α-amylase activity, a rapid increase of maltase activity occurred in the endosperm tissue of germinating rice seeds after about 4 days of the seed imbibition. The overall pattern of the 2 hydrolytic enzyme activities strongly suggest that amylolytic breakdown is the major metabolic route of starch utilization in the germinating rice seeds. Results of the chemical analyses of sugar constituents as well as the measurements of sucrose synthetase activity show that the scutellum is the site of sucrose synthesis in the germinating rice seeds. It is thus supported that glucose derived from the reserve starch in endosperm is transported to scutellum, where it is converted to sucrose. Sucrose is further mobilized to the growing tissues, shoots and roots.

The enzymic synthesis of ADP-glucose and UDP-glucose by chloroplastic pyrophosphorylase of bean and rice leaves has been demonstrated by paper chromatographic techniques. In both tissues, the activity of UDP-glucose-pyrophosphorylase was much higher than ADP-glucose-pyrophosphorylase. Glycerate-3-phosphate, phosphoenolpyruvate and fructose-1,6-diphosphate did not stimulate ADP-glucose formation by a pyrophosphorylation reaction. The major metabolic pathway for UDP-glucose utilization appears to be the synthesis of either sucrose or sucrose-P. On the other hand, a specific precursor role of ADP-glucose for synthesizing chloroplast starch by the ADP-glucose-starch transglucosylase reaction is supported by the coupled enzyme system of ADP-glucose-pyrophosphorylase and transglucosylase, isolated from chloroplasts. None of the glycolytic intermediates stimulated the glucose transfer in the enzyme sequence of reaction system employed.

Ureter-ligated rats, whose blood urea nitrogen concentration equalled that of nephrectomized animals, responded nearly like normal controls to bleeding or phenylhydrazine anemia, and erythropoietin was demonstrated in their plasma. This eliminates the urea retention as a depressing factor of erythropoiesis in uremia. Bilaterally nephrectomized or mercury-bichloride poisoned rats did not respond significantly to anemic stimuli. No erythropoietin was found in the plasma of bled or phenylhydrazine-poisoned nephrectomized rats. The injection of erythropoietin produced significant increases in the erythropoiesis of nephrectomized or mercury-bichloride poisoned rats, but the response was substantially smaller than in ureter-ligated or sham-operated animals. The presence of funtioning renal (tubular) tissue appears to be necessary for a normal erythropoietic response. Renal formation of erythropoietin with a rapid normal turnover, or the accumulation of an inhibitor, distinct from urea and normally inactivated by the kidneys, are discussed as possible mechanisms.

Three cases of the aortic arch syndrome with cardiomegaly and aortic calcification as cardinal symptoms were reported. Fifteen necropsy cases of pulseless disease in Japan were reviewed chiefly about heart involvement, sites of lesion in vascular system and etiological consideration. These reported cases suggest that there is a heart lesion produced by the same cause as the generalized idiopathic arteritis.