1. Cyclophosphamide (endoxan-asta) was injected into the yolk sac of chick embryos on the 3rd through the 6th days of incubation in doses varying from 0.035 mg to 0.08 mg and was found to be more lethal than teratogenic. 2. Mortality rate of the chicks was greater when the drug was given earlier in development (51.2% in the 3rd day injections and 16% in the 6th day group). Higher doses (0.08 mg on 5th day) caused 86. 6% mortality. 3. Teratogenic effects produced a spectrum of malformations resulting in beak defects, eye defects. exencephaly/encephalocele, deformities of limbs and toes, rudimentary wings, ectopia viscerum, skeletal defects and stunting of growth. These show marked resemblance to the malformations produced by cyclophosphamide in rats and mice. 4. Dose of 0.05 mg on 5th day deformed maximum number of chicks (27. 45).

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1. Malformations of the ear in the ddN mouse fetuses resulting from maternal I. P. administration of 15.000 I. U. water miscible vitamin A solution were observed at every 24 hours interval from 9 to 18 of gestation. 2. The malformations of the external acoustic meatus, ossicles and bone labyrinth of the internal ear paralleled in degree those of auricle. 3. The Corti's organ and the ampullar crista of the vestibule were slightly retarded in development but did not reveal any malformation.

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[in Japanese]

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[in Japanese]

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This paper reports results of the in vitro tests of chromosomal radiosensitivity in ten children and three adults with normal karyotypes as controls, 13 patients (children) with chromosomal abnormality and six translocation carriers (adults). Peripheral blood samples from each individual and skin fibroblast cultures from eight control children, nine patients with chromosomal abnormalities and one translocation carriers were irradiated with 10 and 100 rads. Non-irradiated duplicate cultures were used as contrlos. Blood cultures were harvested after 52 hours of incubation, while fibroblast cultures were harvested 24 hours after irradiation. The frequency of chromosomal breakage caused by irradiation was calculated by subtracting figures for non-irradiated samples from those for irradiated samples. The number of chromosome-type breaks per cell/rad in normal controls was 0.0023±0.0010 for children and 0.0020±0.0009 for adults in lymphocytes, and 0.0048±0.0016 for fibroblasts from children. In patients the number of breaks per cell/rad was 0.0051±0.0015 in lymphocytes and 0.0081±0.0017 in fibroblasts, and in carriers was 0.0040±0.0018 in lymphocytes and 0.0063±0.0017 in fibroblasts. In comparison with age-matched controls, significantly elevated frequencies of breaks per cell/rad were observed in cultured lymphocytes and fibroblasts of patients, and in cultured lymphocytes of translocation carriers. After irradiation with 100 rads the number of dicentrics and rings per cell was significantly greater in both patients and carriers of chromosomal abnormalities than in controls. Threrfore, chromosomes of cells from patients with chromosomal abnormalities and translocation carriers were significantly more radiosensitive in vitro than those of controls.

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