The role of thyroxine in the differentiation of the organ of Corti

The developmental basis of the association of congenital deafness with hypothyroidism observed in several human syndromes was earlier investigated by experiments on mice. The offspring of females with chemically induced hypothyroidism were found to have malformations of the organ of Corti, showing that thyroxine played a role in the differentiation of this organ. The present study was undertaken to identify the site of action of the hormone in the developing organ. It appears to be the epithelium of the inner spiral sulcus.

[Effect of 2,4-diamino-5-chlorphenyl-6-ethylpyrimidine on the oncorporation of P32-phosphate into adenylic nucleotides of rat embryo and placenta]

Teratogenic doses of antimalaria preparation, 2,4-diamino-5-p-chlorophenyl-6-ethylpyrimidine (chloridine), known in biochemistry as a specific inhibitor of dihydrofolate reductase, result in the decrease of 32P-phosphate incorporation into ATP and ADP, coupled with the inhibitions of DNA synthesis, in rat embryo and placenta on 13th day of development, while the incorporation of 14C-formiate into free nucleotides of acid soluble embryo and placenta fractions (at the same intervals after teratogen injections), is the same as in the control. These data show that the primary blocking of folate cycle and DNA biosynthesis in 13 days old embryos with induced anomalies of development is some way coupled with disturbances of ATP metabolism.

Aspects of the teratology of cyclophosphamide (NSC-26271)

Wistar-derived rat embryos were most sensitive to maternally administered cyclophosphamide on Days 9.5 and 10.5 of gestation and to chlorambucil on Day 9.5 of gestation. The spectrum of malformations and the dose-response behavior of both drugs were similar. Chlorambucil was three times more potent than cyclophosphamide on an mg/kg basis. The drugs showed additive behavior when administered in combination. The teratogenic effects of the individual or combined drugs were reduced by protective doses of cysteine or glutathione. Studies with analogs of cyclophosphamide have suggested that the whole molecule is involved in teratogenesis.

Structural and functional abnormalities in the sex organs of male offspring of mothers treated with diethylstilbestrol (DES)

The in utero effects of DES (Diethylstilbestrol) on the human male genital tract are reported in this follow-up study of male offspring of DES-treated mothers. Both anatomical and functional abnormalities were significantly greater in the DES-exposed males as compared to control males whose mothers were all participants in a prospective, randomized double blind study of the effects of DES on pregnancy at the Chicago Lying-in Hospital during the early 1950s. Epididymal cysts, hypotrophic testes and capsular induration of the testes were among the more common genital lesions found in 27% of 134 DES-exposed males as compared to a 7% incidence in 119 control males. Spermatozoa analyses revealed severely pathologic changes (Eliasson score greater than 10) in 29% of 28 DES-exposed males and 0% of 18 control males (with or without genital i.e., physical abnormalities). Abnormal findings on physical examination combined with sperm abnormalities (Eliasson score greater than or equal to 5) were found in 29% of DES-exposed males versus 0% of 18 control males. Cytologic examinations did not reveal malignant cells from the following materials: urines before and after prostatic massage or ejaculation, prostatic fluids and aspirates from epididymal cysts.

Congenital malformations in infants of diabetic mothers

In a series of 701 infants born to diabetic women between 1950 and 1974 ,57(8-1 percent) had congential malformations which is a rate three to four timeshigher than in the normal populations of Birmingham.. In 26 cases(3-8 per cent) the malformations were fatal and accounted for 26 per cent of the perinatal mortality in the series. Central nervous system, cardiovascular and skeletal abnormalities were equally common and there was a high incidence of anencephalus, spina bifida, transposition of the great vessels and sacral dysgenesis...