Cytological features of oogenesis and their evolutionary significance in the fern Osmunda japonica.

The development of the egg and canal cells in the fern Osmunda japonica Thunb. was studied during oogenesis by transmission electron microscopy. The mature egg possesses no fertilization pore and no typical egg envelope. In addition, an extra wall formed around the canal cells during oogenesis and apparently blocked protoplasmic connections between the egg and the canal cells. The periodic acid Schiff (PAS) reaction revealed that the extra wall was most likely composed of polysaccharides. Maturation of the egg was accompanied by the formation of a separation cavity above the egg and by some changes in the morphology of the nucleus and cytoplasmic organelles. The chromatin of the nucleus becomes condensed and the upper surface of the nucleus becomes closely associated with the plasmalemma. Amyloplasts in the egg cytoplasm were numerous and conspicuous, with most in close proximity to the nucleus. Finally, the cytoplasm on one side of the egg became vesiculated and the overlying plasmalemma was easily disrupted. These cytological features of the egg and the canal cells during oogenesis in O. japonica are markedly different from those of the leptosporangiate ferns and suggest a significant evolutionary divergence in reproductive cellular features between Osmundaceae and leptosporangiate ferns.

[Stage I testis teratoma in adults: treatment options and recurrence factors].

OBJECTIVE: To study the clinical outcomes of stage I testis teratoma, including pure teratoma, and to provide information on the treatment options for this disease. METHODS: We retrospectively analyzed 27 cases of orchiectomy for stage I testis teratoma, excluding epidermoid cyst, and investigated its recurrence associated with treatment methods and clinicopathological factors. RESULTS: Four of the 27 cases relapsed, all in the orchiectomy group and confined to the retroperitoneal region, 3 with and the other 1 without risk factors, but with no death. No recurrence was found in those treated by orchiectomy followed by chemotherapy with bleomycin, etoposide and platinum (BEP). The total rate of recurrence was 15.8%. No severe side effects were observed in the 9 patients undergoing adjuvant BEP chemotherapy. CONCLUSION: Risk factors may increase the recurrence rate of stage I testis teratoma, while postoperative adjuvant chemotherapy can reduce it, including that of pure teratoma, though surveillance policy remains the most popular option after orchiectomy.