Aichi Yoshida

A Scanning Electron Microscope Study of Myoepithelial Cells in Exocrine Glands

SummaryBy removing connective tissue components with enzymatic digestion followed by HCl-hydrolysis, myoepithelial cells (MECs) of the terminal portion in a variety of exocrine glands of the rat were examined with the scanning electron microscope.The profile of MECs varied considerably from gland to gland; MECs in the lactating mammary gland have a few long cytoplasmic processes in close contact with those of adjacent cells forming a continuous network around the terminal portion. Those of the exorbital lacrimal gland are stellate with many thin radiating processes with tapered ends that terminate freely. MECs in the sublingual gland are characterized by a number of broad and extensive cellular processes. MECs in the submandibular gland are similar in appearance to those of the exorbital lacrimal gland, but with more extensive cellular processes that form a more or less continuous network with those of the adjacent cells. No MECs were observed on the terminal portion of the parotid gland where the cells appear to be lodged on the intercalated duct.The relative surface area covered by MECs per terminal portion was also found to vary significantly, being 24% in the lactating mammary, 17% in the exorbital lacrimal, 48% in the sublingual, and 25% in the submandibular glands.The findings are discussed in relation to the physical properties of secretions in different glands.

Choriocarcinomatous change with immunocytochemically HCG-positive cells in the gastric carcinoma of the males

Gastric choriocarcinoma is a rare tumor and attracts interest because of its controversial pathogenesis. The present study reports a choriocarcinomatous change with immunocytochemically hCG-positive cells in the gastric carcinoma. The patients were males, one was 41 years old and the other 42 years old. The tumor of both cases consists of adenocarcinoma and choriocarcinoma. A sequential process of morphological transition of the adenocarcinoma to the choriocarcinoma can be traced. Indirect immunoperoxidase stain (PAP method) for human chorionic gonadotropin (hCG) demonstrates the localization of hCG in the syncytiotrophoblasts. Small number of cytotrophoblasts are weakly positive. None of the components of adenocarcinoma of both cases is positive for hCG. Human placental lactogen is not demonstrated in both cases. Stain for pregnancy specific β-1 glycoprotein is weakly positive in the adenocarcinoma of one case but not in the choriocarcinoma. In one case, the concentration of hCG was 19.9mIU/ml in the preoperative serum and decreased to 1.2mIU/ml after gastrectomy. HCG production by gastric carcinoma was discussed with regard to possible pathogenesis of gastric choriocarcinoma.

Primary signet-ring cell carcinoma of urinary bladder

Abstract The tenth reported case of primary signet-ring cell carcinoma of the urinary bladder is described. This adenocarcinoma of varying degrees of differentiation (predominantly, signet-ring cells and, partially, poorly differentiated cells and mucin-secreting columnar cells which were arranged in glandular pattern) involved almost the entire mucosa, invading the inuscularis of bladder wall in places, ejaculating ducts, and prostatic ducts.

Murine Model for Immunoprophylaxis of Cytomegalovirus Infection

Murine cytomegalovirus was utilized as a model for human cytomeglovirus, which had no experimental animal, to study immunoprophylaxis of the cytomegalovirus infections. Murine cytomegalovirus (MCMV) serially propagated in mouse embryonic fibroblasts had lost pathogenicity for weanling mice including neonatally thymectomized mice. The cell culture‐adapted MCMV was effective as a “live, attenuated virus vaccine” against challenge by virulent, mouse‐passaged MCMV. The immunization via intraperitoneal route protected mice from every parameter of MCMV infection. These included clinical signs, virus replication, histopathology and mortality. The protective immunity was active against the virulent MCMV which was not neutralized by the rabbit anti‐attenuated MCMV serum.

Non-invasive thymoma with widespread blood-borne metastasis

A 49 year-old woman with multiple coin lesions in both lungs died three months after admission to hospital for progressive neurologic manifestations due to increasing intracranial pressure. At autopsy, neoplastic lesions were found in the anterior mediastinum, lungs, spleen, cerebrum, liver, right kidney and right ovary. Microscopically, the tumor was composed predominantly of epithelial cells which were arranged in an hemangiopericytoma-like pattern. Rosette formation was also prominent. This case was diagnosed as a thymoma with widespread blood-borne metastasis. Previous reports of metastasizing thymomas are very uncommon.

NONCHROMAFFIN PARAGANGLIOMA IN THE NOSE and PARANASAL SINUSES

Nonchromaffin paraganglioma occurring in the nose and paranasal sinuses are extremely rare. The authors have experienced a case of nonchromaffin paraganglioma of nasal cavity which extended to the epiphar‐ynx. To our knowledge, this reported case is the fourth case that has appeared in the world literature.

Serum alpha-fetoprotein-positive gastric carcinoid with liver metastasis

The patient was a 60-year-old Japanese male. He complained of epigastralgia and right chest pain of 4 months duration, and general malaise, nausea and vomiting of 2 months duration. Physical examination revealed on the right third rib a tender mass with a diameter of 2 cm and hepatomegaly with a multi-nodular surface and red palms. There were no signs of carcinoid syndrome, such as cutaneous flushing. Laboratory examinations disclosed certain biochemical alterations; alkaline phosphatase 810 IU/l, γ-glutamyl transpeptidase (γ-GTP) 2090 IU/l, carcinoembryonic antigen (CEA) 23.5 ng/ml and α-fetoprotein (AFP) 6,800 ng/ml. Both HBs-Ag and HBs-Ab were negative. The patient died in a uremic state, with rapid increases of jaundice and ascites. Autopsy revealed gastric carcinoid with extensive metastases to the liver and the bone marrow. Tumor cells showed argyrophilia but not argentaffinity. Immunofluorescence specific for AFP was positive in the hepatocytes, particularly those adjacent to the metastatic tumor cells but not in the tumor cells, either primary or secondary. 79 Cases reported in Japan of serum AFP-positive malignant tumor other than hepatocullular carcinoma and certain other malignancies of germ cell origin are reviewed and discussed.

Carcinoid tumor of the uterine cervix

A case of carcinoid tumor of the uterine cervix is reported. The patient was a 76-year-old Japanese woman with a complaint of vaginal bleeding. She was clinically diagnosed as stage IVb carcinoma of the uterine cervix. Light microscopically, the tumor was characterized by formation of solid cell nests and, in limited areas, glandular structures. The tumor cells in solid cells nests showed positive argyrophil reaction but were negative for argentaffin reaction. At the ultrastructural level, the cytoplasm of the tumor cells contain numerous neurosecretory granules, microfilaments and well-developed Golgi complexes. On the bases of histochemical and electron microscopic features of tumor cells, the tumor was diagnosed as carcinoid tumor of the uterine cervix.

Ultrastructure of mammary carcinomas in male rats induced by 7,12-dimethylbenz(a)anthracene

SummaryThe morphology of mammary tumors induced by 7,12-di-methylbenz(a) anthracene in male rats was investigated by light and electron microscopy. All tumors induced in male rats were carcinomas with prominent epithelial growth which shows a medullary or cribriform appearance. Neither mammary dysplasias nor fibroadenomas were induced in male rats. Foci of adenoid cystic carcinoma were encountered in some parts of tumors. Papillary and/or tubular patterns, which have been observed frequently in mammary carcinomas in female rats, were not prominent histologic features in male rats. Secretory activity was not remarkable. The morphology of mammary carcinomas in male rats was unchanged in primary and transplanted tumors under various hormonal conditions. This finding supports our previously published results that the mammary carcinomas in male rats are hormone-independent, althugh our previous biochemical study revealed that the tumors contain both estrogen and estrogen-dependent progesterone receptors.

Scanning electron microscopy of 7,12-dimethylbenz(a)-anthracene-induced mammary carcinoma in the female Sprague-Dawley rat

SummaryThe surface morphology of normal mammary glands and mammary carcinomas was examined under the scanning electron microscope after digestion of connective tissue and the basal lamina with collagenase, hyaluronidase and hydrochloric acid (HC1).Two types of cells were clearly identified in the acini of normal glands; granular epithelial cells and stellate myoepithelial cells. Spindle-shaped myoepithelial cells lying longitudinally along the mammary ducts were also recognized.7, 12-dimethylbenz(a)anthracene-induced mammary carcinomas consisted or irregular masses of cells which had polypoid or columnar processes with rounded heads; the masses appeared to be composed of a single type of rhomboid cell. The tumors lacked the stellate or spindle-shaped myoepithelial cells found in normal acini and ducts.