Probodh K. Srivastava

Biology of reproduction in the squirrel monkey (Saimiri sciureus): I. The estrus cycle

Results of a study to evaluate the length and specific characteristics of the estrus cycle in the squirrel monkey is presented. The estrus cycle was found to be 18–20 days long. Neither menstrual flow nor a cyclic swelling of the external genitalia was observed. A vulvar plug of desquamated vaginal cells was often, but not consistently observed a day prior to or on the day of estrus. Most pronounced cyclic changes in the exfoliated vaginal cells occurred during December through March of both the calendar years of the study.

Somatic chromosomes of squirrel monkey (Saimiri sciureus)

The chromosome complement of 2 male and 15 female adult squirrel monkeys (Saimiri sciureus) have been studied in peripheral blood and kidney cultures and bone marrow preparations. The diploid chromosome number is 44. Six of the chromosome pairs are metacentric (isobrachial), 9 pairs submetacentric (heterobrachial) and the remaining 6 pairs are acrocentric (cephalobrachial). The X chromosome is the longest submetacentric (heterobrachial), ranking 5 in order of decreasing size. The Y chromosome is the smallest acrocentric (cephalobrachial) of the complement.A female and male karyotype is presented.

Biology of reproduction in the squirrel monkey (Saimiri sciureus): II. The ovary

Gross and microscopic observations on the squirrel monkey ovary is described. The luteal tissues are present in two broadly distinct stages of activity. The degree of follicular development appears to be affected by the level of luteal activity. Circumstantial evidences have been presented to indicate that squirrel monkey females may be an induced ovulator.

Y‐chromatin fluorescence in human buccal smear

The buccal smear is an excellent specimen in which to screen interphase nuclei for the fluorescent stained Y‐chromosome. Not only is the specimen easily obtained and processed, but the Y‐chromatin stands out prominently in condensed form. Fluorescence size is quantitated by ocular micrometric measurements.

Pattern of Y‐chromatin fluorescence in an XYY man

Study of the buccal smear from an XYY individual revealed the Y‐chromatin fluorescence to be single, double, split or a combination of single and split in 16, 53, 12 and 4 per cent of the nuclei, respectively. In 3 per cent of the nuclei, unidentifiable multiple fluorescing bodies were present. Fluorescence size was quantitated by ocular micrometric measurements.

In-vivo chromoclastogenic effects of aflatoxin B1 in the hepatocytes of chinese hamsters

In-vivo effects of aflatoxin B1 were studied in the chromosomes obtained from the regenerating hepatocytes of chinese hamsters. Chromatid gaps were preferentially seen in the known heterochromatic areas of the chromosome pair one, X and Y. Asynchronous divisions of the centromere were seen in both the control and treated animals, however, the frequency was 8–10 times higher in the latter.

Biology of reproduction in the squirrel monkey (Saimiri sciureus): III. Ultrastructure of the endometrial glandular cell during estrogen and progesterone feeding

Electron microscopic study of the endometrial glandular epithelium of the squirrel monkey (Saimiri sciureus) revealed the following three types of cells (1) principal, (2) mucus, and (3) ciliated cells. We further observed that these cells undergo morphologic changes in response to estrogen and progesterone feeding. The morphologic changes observed in the principal and mucus cells represent phases in the transformation of relatively poorly differentiated cells into mature functioning cells. The mucus cells elicit an accelerated maturative and functional change. The morphologic changes of the ciliated cells were least obvious.