An animal model for the XXY Klinefelter's syndrome in man: tortoiseshell and calico male cats

A review of the chromosome findings in 25 male tortoiseshell or calico (T-C) cats showed a variety of aneuploidy, polyploidy, mosaicism, and chimerism. An XXY-complement was included in the chromosome makeup of 16 of the 25 cats. Almost all of these cats were sterile. Testicular pathologic changes, when recorded, appeared comparable with that of human XXY Klinefelter's syndrome. The findings in 2 male T-C cats were presented as representative models of XXY Klinefelter's syndrome in man. Other findings in human Klinefelter's syndrome have not been looked for in the feline models, but a plan for this is underway. A review also was made of the historical steps leading to our present understanding of the Klinefelter syndrome including the role of Felis catus. An explanation of cat coat-color genetics clarified why "black" and sex-linked "orange" coloration can appear together normally in XX females and in rare males with 2 different X chromosomes. Thus, male T-C cats were only convenient indicators of underlying sex-chromosome aberrations which were occurring completely independent of coloration.

Mosaicism and lack of fluorescence of Y chromosome

A patient with a female phenotype with XO/XY and possibly XYY mosaicism is presented. In all cells studied, there was no fluorescence of the Y chromosome. It appears that a tendency exists for an association of a defective Y chromosome with chromosomal mosaicism.

A ten year study of ovarian tumors

A study of 213 ovarian tumors was undertaken with respect to the published assumption that there may be a relationship between presence of crystals of silicate in the ovarian tissue and neoplastic transformation. The histological review gave the opportunity to classify these tumors according to the recommendations of the World Health Organization. The frequency of histological types, age distribution and the site of involvement were determined. These data were compared to those in the literature. Our findings confirm the high incidence of serous tumors and bilaterality reported by others as well as the high risk of ovarian cancer in women in their fifties. A comparative study of the age distribution of cytadenomas was made. It suggests that cystadenomas might be considered as a precursor to the cystadenocarcinomas because of their appearance at younger age. A deliberate search for silicate crystals in periovarian adhesions and in tumor tissue showed a minimal incidence of crystalline material. This does not support a direct relationship between silicate crystals and ovarian tumors. However, it is suggested that neoplastic changes may occur in the ovarian surface as a result of adhesions engendered by deposition of silicate crystals.

The effects of dexamethasone on the peripheral plasma concentrations of androstenedione, testosterone and cortisol in the pregnant rhesus monkey

The concentrations of androstenedione, testosterone and cortisol have been measured in the maternal peripheral plasma of normal pregnant rhesus monkeys (Macaca mulatta), and in rhesus monkeys treated daily with dexamethasone during late pregnancy. During the last 30 days of pregnancy, the mean plasma concentrations of androstenedione, testosterone and cortisol were about 1400-2000 pg/m1375-425pg/ml and 300-400 ng/ml, respectively. None of these steroids increased significantly before parturition. As there was no rise in maternal androgens in late pregnancy when plasma estrogens increase sharply, it suggested that his elevation of plasma estrogens is related to an increase of fetal precursors Dexamethasone treatment resulted in 90% suppression of plasma cortisol and 40%-60% suppression of androstendione and testosterone. As the suppression of maternal androgens was of lesser magnitude than the decline of plasma estrogens, and as the androgens did not continue to fall with continuing dexamethasone treatment as did the estrogens, these findings also suggest that the decline in plasma estrogens is related in large part to suppression and atrophy of the fetal adrenals.

The concentrations of androgens, oestrogens, progesterone and luteinizing hormone in the serum of foetal calves throughout the course of gestations

The concentrations of luteinizing hormone (LH), progesterone, testosterone, androstenedione, oestrone and oestradiol in mixed umbilical cord blood taken from foetal calves during months 3 to 9 of gestation have been measured by radioimmunoassay. The levels of progesterone were low (compared with those in maternal plasma) and constant during pregnancy. There were large variations in the concentrations of androstenedione, oestrone, oestradiol and LH, with lower values found during months 7 to 8 of gestation. Significant differences (P < 0·05–< 0·001) in hormone levels between male and female foetuses were found for testosterone, LH, and the oestrogens during months 3 to 7, 3 and 4, and 7 and 8, respectively. No significant differences (P > 0·05) between sexes were found at any time between the concentrations of progesterone and androstenedione.