1. Vitamin E has a topical action, accelerating the hair growth of rabbits.
2. When 0.5% α-tocopherol and α-tocopheryl acetate lotions were applied, the effect was recognized in as early as 2 weeks and it became marked after 4 weeks, changing the aspect of the hair growth. Weekly hair growth reached the maximal level, 2.4 times that of the control.
3. Vitamin E shortened the period reaching the cessation of hair growth. In the present experiment, the period was 10 weeks at the vitamin E applied parts and 13 weeks at the control part.
4. Little difference was observed between α-tocopherol and α-tocopheryl acetate, but the former seemed to have a rather higher immediate action.

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1. The formation of protein-thiamine complex (mixed disulfide) in the reaction of iodine-oxidized egg albumin and thiol-type thiamine or O-benzoylthiamine (reaction II) proceeds according to pseudo-first order kinetics in its initial stage where SS groups of the protein is in excess to the thiamine thiol.
2. Rate constant is larger in the O-benzoylthiamine reaction than in that of thiamine at each temperature, but the constants are both smaller than that of the reaction between disulfide-type thiamine and SH groups of heat-denatured albumin (reaction I).
3. Activation energies for the reactions of thiamine and O-benzoylthiamine with oxidized protein are both about 30 kcal per mole. This shows that the reaction of the type II needs the larger energy than the reaction of type I.
4. Applying the absolute reaction rate theory, thermodynamic quantities of the reactions in their activated state were calculated.
Entrorpy of activation is negative for reaction II, and positive in reaction I. However, heat of activation and free energy of activation are positive and fairly large in the two reactions, showing the endothermic nature of the reactions. It is further confirmed from these kinetic data that the thiamine-protein complex is formed by the covalent bound through chemical interactions.

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The young rats fed on a myo-inositol-deficient diet showed no doubt the increase in body weight during the initial 45 days of breeding, and was scarcely found any symptoms of spectacled eye or alopecia in appearance, even after the prolonged breeding for more than 3 months. However, there was a marked difference in the growth rate between the animals fed on a myo-inositol-deficient diet and those fed on a myo-inositol-containing diet. The mean daily increase in body weight of rats fed on 0.5 to 2.0mg of myo-inositol was fairly higher than that of those fed on a myo-inositol-deficient diet. Four trials of experiments were performed with high reproducibility.

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The levels of the enzymes involved in the biosynthesis and degradation of flavin compounds in spinachs were investigated.
1. These enzymes are localized in the cytoplasm of the cell.
2. The activities of riboflavin synthetase, riboflavin kinase and FAD pyrophosphorylase are distributed consistently.
3. Although the activity of hydrolyzing FMN by the acid phosphatase was considerably higher than that of riboflavin kinase, it was strongly inhibited by the nucleotides, inorganic phosphates and metallic ions.
4. The low affinity of FMN to the acid phosphatase and its low content in green leaves may to decrease the rate of FMN hydrolysis in vivo.

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Neuromuscular blocking of thiamine and its derivatives upon sciatic nerve-sartorius muscle preparation of cold blooded animals was observed.
Thiamine, cocarboxylase (TDP) and pyrithiamine as well as oxythiamine blocked the neuromuscular transmission. Their critical concentrations were about 0.005 M and their blocking times were several decades of minute. From these results, it can be presumed that their action on the neuromuscular transmission must be quite independent of their coenzymatic activities. Derivatives of thiamine in thiol form had also the blocking action. Therefore, the quaternary nitrogen does not play a leading role in the neuromuscular blocking action of thiamine and its derivatives.

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The effects of the protein and amino acid composition in the diet on the biosynthesis of protein-bound lipoic acid, which is considered to be the active form of lipoic acid for oxidative decarboxylation of α-keto acids, such as pyruvic acid and α-ketoglutaric acid, were observed and the following findings were observed.
1. Decreased incorporation of lipoic acid into the total mitochondrial protein of the liver was revealed in the low protein group.
2. The incorporation of the acid per mg nitrogen of liver mitochondria of the low protein group was unexpectedly higher than that in the standard diet group.
3. In the lysine-, tryptophan- or threonine-deficient group, the incorporation of lipoic acid into the mitochondrial proteins was decreased, but in the methionineor phenylalanine-deficient group, almost the same incorporation was observed as the standard diet group.

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1. The abnormally high rate of urinary excretion of L-ascorbic acid in alloxan-diabetic rats was found to be partially the result of a lowered rate of destruction of L-ascorbic acid in the liver caused by insulin deficiency.
2. The synthesis of L-ascorbic acid from D-glucuronolactone and the destruction of L-ascorbic acid were found to decrease in the liver of tumor-bearing rats.

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1. When vitamin D₂ in ethylene dichloride was allowed to stand with acetyl chloride (2 per cent of total volume) for 30 minutes at room temperature, it was easily isomerized to isotachysterol.
2. When antimony trichloride reagent without acetyl chloride was added to the isotachysterol, no color was produced. Therefore, it may be concluded that the isomerization of vitamin D to isotachysterol has no relation with the colorimetric reaction of vitamin D with antimony trichloride reagent containing acetyl chloride.

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The urinary excretion of lipoic acid in 2 hours in the early morning in healthy and sick children was determined using microbioassay of Streptococcus faecalis R and the following findings were obtained.
1. It was proved that the urinary excretion of lipoic acid in healthy children increased with the gain of the body weight. A significant correlation was found between urinary excretion and body weight. The amount of the urinary excretion of the acid in healthy children was 25 to 45mg per kg body weight in 2 hours in the early morning.
2. The urinary excretion of lipoic acid in the patients suffering from renal diseases, such as acute gomerulonephritis or nephrotic syndrome, was decreased and the amount of excretion in 2 hours in the early morning was 15mg per kg body weight on the average. The decrease returned to normal with clinical restoration.
3. In the case of malnutrition due to several causes, the tendency of increase in urinary excretion of lipoic acid was observed.
4. Percentage urinary excretion of lipoic acid in 2 hours following intravenous injection of 1mg α-lipoic acid per kg body weight ranged from 0.2 to 0.7% and decreased in renal diseases.

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The effect of dietary composition and anabolic steroid hormone on the lipoic acid metabolism in weaning and mature rats were observed and the following findings were obtained.
1. The urinary excretion for 24 hours, and the levels in the serum, liver and kidney of lipoic acid in mature rats were, on an average, 77mμg, 17.5mμg/ml, 2880mμg/g and 2700mμg/g, respectively and the nitrogen contents of the liver and kidney were 29.0 and 31.6mg/g respectively.
2. The urinary excretion and the serum level of lipoic acid in the low protein diet group were slightly lower than those in the standard diet group. In such animals, the lipoic acid content in the liver was remarkably decreased in correlation with the decline of nitrogen level.
3. The influence of a low protein diet was stronger in the weaning rats than in the mature ones. The lipoic acid level in the liver was decreased to 50% of the normal level.
4. The effect of amino acid deficiency of the diet on the content of lipoic acid in the liver was examined and the influence of tryptophan deficiency was the strongest, followed by that of lysine deficiency.
5. The effect of the anabolic steroid hormone on the weight gain, serum protein concentration, urinary excretion of lipoic acid, serum lipoic acid level, weight of the liver, kidney, or testicle, and nitrogen and lipoic acid contents of these tissues under several different conditions of the diet in rats were investigated.
The anabolic effect on nitrogen metabolism and the influence on the lipoic acid metabolism by this type of hormone were most remarkable when the rats were fed at first the low protein diet and then that with a sufficient quantity of protein. On the contrary, the catabolic effect of 19-norandrosterone phenylpropionate was observed in the rats fed a sufficient or low protein diet.

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When assaying the vitamin B₁₂ and folate activity of material obtained by needle biopsy of the liver, it is important because of the small size of the sample to be able to choose an extraction method suitable for both estimations.
The releasse of vitamin B₁₂ from the bound form depends on heat rather than enzyme extraction, whereas the release of folate active material requires preliminary treatment with enzymes such as papain or chicken pancreas. Both materials were tested at various pH levels and both gave comparable results. However, the papain contained no vitamin B₁₂ activity and less folate activity than chicken pancreas and had the added advantage of requiring less heat treatment.

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Nine healthy women served as the subjects for the first to the fourth experiments. The effect of tryptophan deficiency on the metabolic products of tryptophan and niacin was examnied. Urinary nitrogen, riboflavin, anthranilic acid, xanthurenic acid and N¹-methylnicotinamide, NAD and NADP in the blood were determined. When tryptophan was deprivated from the amino acid mixture for the nitrogen source, the excretion of total nitrogen, riboflavin, anthranilic acid and N¹-methylnicotinamide was increased, but that of xanthurenic acid was decreased.
The ratio of NAD to NADP became lower. The difference of the effect between L-tryptophan and the D-isomer on the excretion of the metabolic products was not seen.

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