Testicular germ cell differentiation in vivo

The effects of artificial cryptorchidism and surgical reversal on spermatogenesis were examined in mice. Only undifferentiated type A spermatogonia were present as germ cells in cryptorchid testes. The surgical reversal of cryptorchidism resulted in regenerative differentiation of mature germ cells as judged by testicular weight, histologic examination, and increase in the specific activity of lactate dehydrogenase-X. Leydig cell function was also examined by assessment of the weight of target tissues of androgen. They showed a unique change following the surgical reversal. Thirty days after surgical reversal, hyperfunction of the Leydig cells was observed, and the testes became normal after 60 days.

Clear cell carcinoma of the ovary: light and electron microscopic studies

Twelve cases of ovarian clear cell carcinoma were studied histologically. Four cases were examined electron microscopically and compared with other conditions. Five tumors were directly connected with ovarian endometriosis. They were histologically classified into a tubular type with hobnail cells and a solid type without tubular pattern or hobnail cells. Electron microscopic figures of the tumor cells are identical having large nuclei, abundant glycogen, lamellated RER, few lipid droplets, and sparse but well-developed microvilli. The basophilic dark cells frequently encountered in the tubular type are morphologically quite similar to clear cells excepting for sparsity of glycogen and lipid droplets. Alveolar arrangement of 6 to 10 tubular structures (honeycomb structure) resembling alveolate structure seen in late secretory endometrium was found in tumor cells of one case. Ultrastructural feature of clear cell carcinoma closely resemble those of Arias-Stella endometrium and clear cell carcinoma of endocervix suggesting their Muellerian origin.

An autopsy case of type II glycogenosis

An autopsy case of Type II glycogenosis was reported with detailed description of ultrastructural findings. In addition to two typical patterns of glycogen deposition, membrane-bound lysosomal glycogen and membrane-free cytoplasmic glycogen, we observed numerous vacuolar structures in liver cells and a large deposition of nomogeneous materials between fragmented myocardial fibrils. These findings were briefly discussed in this manuscript.