A case of left atrial myxoma accompanied by pancytopenia and pathological findings suggestive of pulmonary hypertension

A case of left atrial myxoma accompanied by peculiar symptoms is reported. A 15-year old boy had progressive congestive heart failure and three episodes of acute attacks of panctyopenia. The anemia was accompanied by helmet-shaped, broken red blood cells, erythroid hyperplasia and elevation of indirect bilirubin. The thrombocytopenia gave rise to hemorrhagic tendency of the skin and mucous membrane. The leukocytopenia was seen at the same time. The patient also had general constitutional disturbances showing generalized malaise, persistent fever, elevation of erythrocyte sedimentation rate, positive C-reactive protein, pulmonary infection and anginal attacks. Postmortem examinations revealed a left atrial myxoma and intricated pulmonary changes. There was obliterative endarteritis of the left coronary branch and pulmonary arteries. The interstitial pulmonary fibrosis was also prominent. The pancytopenia should have been induced by the mechanical damage of circulating blood cells by the left atrial myxoma. The pathological findings of the lungs were highly suggestive of pulmonary hypertension, which was assumed to be due to mitral block caused by the atrial myxoma.</p

Relationship between immune reactivity and developement of thymic lymphoma by N,N'-dimethylnitrosourea in C3Hf-Bi mice

By subcutaneous inoculation of N, N'-dimethylnitrosourea to adult male C3Hf/Bi mice once a week for 10 consecutive weeks the authors studied the correlation between immunological functions and histological changes in lymphatic tissues at the latent period of thymic lymphoma whose development is known to occur in 100 per cent. As a result, it was found that PFC of the spleen to sheep erythrocytes decreased to about one third the normal level by two weeks, and to one tenth by 8 weeks after initial inoculation of this compound. Hemolysin and hemagglutinin titers of the serum became less than 1 : 2 after 6 weeks and later. As for histological changes in the thymus, disappearance of lymphocytes became marked by 2 weeks, and there appeared tumor cells by 8 weeks. Also the peripheral lymphocytes as well as the total spleen cells decreased in number along with increase of the frequency of inoculation of N,N'-dimethylnitrosourea. These results seem to suggest that the immunosuppressive effect of carcinogen facilitates the development and proliferation of tumor cells possessing tumor specific antigenicity in the course of N, N'-dimethylnitrosourea- carcinogenesis.</p

Brain tumors induced in rats by human adenovirus type 12

Oncogenesis of human adenovirus type 12 in the brain of rats was examined. Newborn rats of Sprague-Dawley and Donryu&#12288;strains were injected intracranially with human adenovirus type 12.&#12288;The incidence of intracranial tumors was 91% (30/33) in SpragueDawley&#12288;and 56% (14/25) in Donryu rats. Except for one tumor nodule&#12288;located in the parietal cortex of a Sprague.Dawley rat, all tumors&#12288;developed in the paraventricular areas or in the meninges. Tumors were quite similar histologically to those induced in hamsters and&#12288;mice resembling the undifferentiated human brain tumors such as medulloblastoma,&#12288;ependymoblastoma and embryonic gliomas. From&#12288;the histological features and primary sites of tumor development, it is&#12288;suggested that the tumors in the brain of rats induced by adenovirus type 12 originate from the embryonic cells in the&#12288;paraventricular area&#12288;and also from the undifferentiated supporting cells of the peripheral&#12288;nerves in the&#12288;leptomeninges.</p

Cryptococcus, Pathological observations of five autopsy cases and one biopsy case

Pathologic, anatomical, and histological findings of 5 autopsy cases and one biopsy case of cryptococcosis have been described. Macroscopically the foci of the lung are grayish white or yellowish white in color and range in size from the small acinous-nodular ones to the larger lobular-nodular ones. In the brain the meninx appears gelatinous and edematous showing many small spots with indistinct boundary and with grayish white color. Lymph nodes infected with fungi are swollen in various degrees. Histologically the foci are mainly consisted of granulomatous inflammation containing giant cells. Besides, there are small degenerative foci having no inflammatory response and the lesions of marked fibrosis; the former will be newly formed foci and the latter the old ones. The size of C. neoformans found in tissue ranges from 3 to 30 &#956;, and the majority of fungi possess thick gelatinous capsule, but some of them in granulative lesions often possess no capsule. From the staining properties the capsule of C. neoformans is believed to be a kind of acid mucopolysaccharide. As for the staining method including general fungi, GOMORI's methenamine silver method is best, especially for the detailed examination of fungus structures, and for the differential diagnosis mucicarmine stain is the most suitable one. In tracing the distribution of the foci in the various organs, it seems that the first attack of this fungus occurs in the lung. The authors have called general attention, through their own experiences, to the fact that the small granulomatous foci caused by Cryptococcus infection, especially in the lung, may often escape the detection at autopsy.</p

A case of histoplasmosis Report 1. Cinical, mycological and pathological observations

In our country it has been believed that there is no histoplasmosis here in Japan. However, from the above clinical signs, radiological characteristics, laboratory tests, pathological and mycological examinations, and experimental findings, we believe this is the first case of histoplasmosis in Japan.</p

Effect of injection of adenovirus type 12 in adult hamsters

Large doses of adenovirus type 12 were injected intraperitoneally into adult hamsters, and development of tumors and other pathological findings were studied in comparison with those in hamsters injected when newborn. Doses of 38~47 TCID60 per gram body weight produced tumors in 3 of 12 hamsters injected at 37~57 days of age. A dose of 170 TCID60 per gram body weight produced tumors in one of 18 hamsters injected at 61~71 days of age, but in none of 18 hamsters injected at 147~174 days of age, while the same dose per gram body weight produced tumors in 24 of 26 hamsters injected when newborn. In hamsters injected at adult ages, the number of tumors per animal decreased and the latent period for tumor development became very long as compared with those in hamsters injected when newborn. Regardless of the age at the time of injection, acute inflammatory change was observed in the peritoneum which later developed into various degrees of peritoneal adhesion. Adenovirus type 3 also induced the peritoneal adhesion. Histology of tumors was studied and discussed.</p

Effect of oncogenic nitrosourea on intraocular tumor induction by adenovirus in rats.

Interference of oncogenic N-nitrosourea in intraocular tumor induction by human adenovirus type 12 in rats was examined. Transplacental administration of methylnitrosourea to rat embryo reduced significantly the latent period of the intraocular adenovirus tumor in each animal whereas in groups preadministered with ethylnitrosourea the decrease in the latent period showed marked individual variation. Preadministration of N-nitrosourea caused little change in the morphology and incidence of adenovirus tumors. The histological picture of adenovirus induced intraocular tumors which developed in each group of rats was that of retinoblastoma-like tumor identical to the tumor induced by single virus injection.</p

Brain tumors in hamsters induced by murine sarcoma virus (Moloney).

&lt;p&gt;Murine sarcoma virus, CS-Moloney substrain, was inoculated intracranially into 2 litters of newborn Syrian hamsters within 24 h of birth. Seven of 12 hamsters which survived more than 30 days developed brain tumors in the cerebral cortex 104 to 153 days, 139 days on the average, after the virus inoculation. The tumors consisted of spindle-shaped, round or polygonal astrocytes which showed a positive reaction for glial fibrillary acidic protein by the immunoperoxidase method.&lt;/p&gt;</p

On the histo-morphological changes of transplantable tumors.

1. When chicken sarcoma virus is serially inoculated on the mouse brain, it loses its carcinogenecity, but when it is inoculated on young chicken, granuloma develops in the liver and lung. When this granuloma is transplanted on adult chicken, a transplantable fibrosarcoma is obtained. 2. According to literature, the originaltumor of the Brown-Pearce cancer is a basal cell cancer, but that imported to Japan in 1953 presented a histological picture of carcinosarcoma. The metastasized tumor of the eye presents a purely cancer tissue, but when this is inoculated on the testis, carcinosarcoma is reproduced. It is therefore considered that the mother cell of the sarcoma is of host origin. 3. MY sarcoma is not a sarcoma, but is a spindle cell cancer. It might be a sarcoma which transformed into a cancer during serial transplantation, but perhaps it was originally a cancer but had been erroneously diagnosed as sarcoma. 4. The tumors we obtained by means of the feeding tests of Yoshida tumor all developed at organs other than those of the digestive tract. They are chiefly reticulo-sarcoma, but others which develop are malignant granuloma in the liver and lung, malignant adenoma in the kidney, papilloma of pelvis, and ependymoma in the cerebral ventricle. Since the discovery of the Yoshida tumor in 1943, serial transplantation has been conducted for 19 years with this tumor not only in Japan but also in foreign countries, but there has been no report to this date that a transformed strain has developed by cell transplantation. It therefore must be considered that the carcinogenesis observed in our feeding tests is a carcinogenesis due to a mechanism completely unlike that of cell transplantation. It has been confirmed by electron microscopy that in the early stage of transplantation of this tumor into the abdominal cavity there was an additional tumor growth due to the anaplastic proliferation of serous cells. 5. During the serial transplantation of viral tumors and/or virus dependent tumors, the tumor sometimes undergoes a morphological change. Though the cause of this is not yet sufficiently elucidated, it is suspected that there is some relationship with virus in the wide sense.</p