Filiberto Cavazos

Ultrastructure of the human endometrial glandular cell during the menstrual cycle.

Abstract The ultrastructure of endometrial stromal cells of normal healthy women in reproductive age is described on days 5, 10, 15, 20, and 25 of the menstrual cycle. The stromal cells, in the course of the normal menstrual cycle, undergo distinctive ultrastructural changes that can be correlated with states of proliferation, differentiation, and maturation. On day 5, the stromal cells are essentially immature, resembling stem cells. On day 10 the cells show the beginning of differentiation toward a fibroblast. Day 15 is characterized by the highest rate of proliferation of the cycle. By day 20 evidence of proliferation has disappeared and most cells now present a fully differentiated fibroblastic morphology. Day 25 demonstrates full maturation of the superficial stromal cells to become predecidual cells.

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.

Giant lysosomes and their associated structures in the normal human endometrium

Abstract The giant lysosomes of the normal human endometrium are spherical or approximately spherical structures reaching diameters of 7 μ or more. Giant lysosomes are present only during the proliferative stage of the menstrual cycle and may be of at least three origins, leukocytophagic, isocytophagic, and autophagocytic. Leukocytophagic giant lysosomes occur as an extension of the process known as emperipolesis. Isocytophagic giant lysosomes occur when portions of isogenic epithelial cells are the phagocytized elements and autophagocytic lysosomes are the result of segregation and digestion of a large portion of the cells own structures. Giant lysosomes seem to be an intermediate stage preceded by formation of a phagosome and followed by a state in which incorporation by the cell of the digested lysosomal contents occurs. A working classification of the giant lysosomes and their associated structures in the normal endometrium is presented.

Ultrastructural effects of norethynodrel and mestranol on human endometrial stroma cell

The ultrastructural effects of 19-nor steroid on the endometrial stromal cells of normal healthy women between the ages of 20 and 30 years is described on days 5, 10, 15, 20, and 25 during the second, sixth, tenth, and fourteenth months of drug administration. When compared with normal stromal cells, the 19-nor steroid stimulated stroma cells manifest ultrastructural evidence of increasingly rapid maturation with predecidual cell formation by day 20 of the second and sixth cycles. As the tenth and fourteenth experimental cycles are approached, predecidual cell characteristics are observed in day 15 stroma cells. The gross effect of norethynodrel and mestranol on the stroma cell is hyperplasia of the rough and smooth endoplasmic reticulum and Golgi apparatus and the gradual accumulation of glycogen. By day 25 the stroma cell assumes a less active state with most of the cytoplasm filled with glycogen and the remainder of the organelles compressed in a perinuclear position.

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.

Ultrastructure of chick tendon fibroblast with special reference to secretory mechanism

Electron-microscope study of chick tendon fibroblast revealed a constant ultrastructural finding of a microtubular-microfibrillar system and an intimate relationship which existed between the microtubular-microfibrillar system and secretory vacuoles. Additionally, the data from this study suggest a mechanism by which newly synthesized collagen molecules are transported and secreted into the extracellular space to be organized into mature collagen.

Uterine peroxidase activity in abnormal human endometrium

Abstract Peroxidase activity in endometrial tissue from women taking an oral progestogen and from women with histories of atypical premenopausal uterine bleeding has been investigated. Enzyme activity throughout the progestogen-induced cycle is similar to that found in normal endometrium. Peroxidase activity is distinctly abnormal in the majority of women with premenopausal bleeding disorders. These observations are discussed in light of their possible significance as another parameter for assessment of endometrial dysfunction.

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.

Uterine peroxidase activity in malignant, hyperplastic, and atrophic endometrium

Abstract Uterine peroxidase activity in endometrial adenocarcinoma, hyperplasia, and atrophy has been studied. This investigation supplements previous studies which have defined uterine peroxidase activity in the normal menstrual cycle, in women receiving an oral progestogen, and in women with premenopausal dysfunctional uterine bleeding. The potential significance of uterine peroxidase activity as an index of the relationship between estrogen and the endometrium is discussed.