Archives of pathology最新文献

The tubules appear to be the primary sites of injury in renal failure and urate nephropathy associated with leukemia. Tubular injury is not always associated with precipitation and phagocytosis of crystals, except in the collecting tubules where cellular changes are invariably caused by intraluminal crystallization of urates. The electron microscopical observations in this communication may apply to the urate nephropathy associated with hyperuricemia of various causes.

These experiments demonstrate that the adminstration of bilirubin does not significantly alter biliary manganese excretion in manganese-loaded animals. Sulfobromophthalein sodium (BSP), which has been shown to afford prophylaxis against manganese-bilirubin cholestasis, significantly increases the biliary excretion of manganese. These results are meaningful in that they indicate that the amount of manganese per se in the bile is not critical in this cholestasis, and suggest that intracanalicular reactions are probably not etiologically critical in this model. They point to the conclusion that the critical cholestatic events are occurring within the hepatocyte. The results also indicate that the biliary excretion of manganese is obligate, and to some extent independent of bile flow. The critical cholestatic events are presumably mediated through the biochemical effects of either a manganese-bilirubin complex or of manganese and bilirubin acting separately but synergistically.

Multiple discrete granulomas were found in bone marrow sections of a young woman who had the typical symptoms and laboratory evidence of infectious mononucleosis. I present a review of findings in this case, together with reports of experimentally induced granulomas mediated by an immunologic mechanism.

Metastases from carcinoma of the breast may involve one or both ureters, and may be a clinically important phenomenon. Two cases are presented and the autopsy experience with 181 cases of metastatic breast carcinoma is reviewed. Ureteral involvement was demonstrated in 8.3% of the cases. Bilateral metastases were common.

On the basis of light and electron microscopical findings in a case of malakoplakia of urinary bladder, (1) we concur with others that malakoplakia is a hyperplastic accumulation of histiocytes, and that the formation of Michaelis-Gutmann bodies is associated with incomplete digestion of phagocytized cell debris; (2) we hypothesize that digestion within phagolysosomes is impaired because of deficient acidification; and (3) we suggest that the defect in acidification in some cases may be related to treatment with drugs that affect the mechanism of phagocytic vacuolar acidification.

The effects of paraquat in hamsters were evaluated to find a rodent model of interstitial pulmonary disease free from spontaneous infection. Because the repeated doses necessary to produce chronic lung injury suggested hypersensitivity mechanisms, concurrently administered Freund adjuvant and adenocorticotrophic hormone (ACTH) were tested separately. Effects were measured by mortality, change in body weight, and morphometric estimate of lung injury. Findings were as follows: (1) only repeated doses in a very narrow range produced chronic interstitial injury; (2) ACTH clearly protected animals from the general systemic and pulmonary effects of paraquat; and (3) adjuvant specifically protected against the pulmonary injury alone. There was no evidence of immunologic contribution to paraquat injury.

Levodopa (3,4-dihydroxyphenyl-L-alanine) was fed at 1.0% of the diet to 60 male weanling Syrian golden hamsters for 48 weeks, followed by control diet for an additional 38 weeks. The incidence of tumors were: three of 60 hamsters with forestomach squamous cell papillomas, one of 60 with leiomyosarcoma of the skin, and one of 60 with cortical adrenal adenoma. Two of 30 control animals developed adrenal adenomas. Hyperplasia of the urinary bladder epithelium occurred in 33 of the treated group, and hyperplasia was not found in the bladders of the control group.

A polypoid squamous cell carcinoma with pseudosarcomatous stroma of the urinary bladder was studied electron microscopically. The epithelial component was a typical squamous carcinoma that consisted of cells with abundant bundles of tonofilaments that converged toward well-developed desmosomes; keratohyalin granules were also seen. The stroma consisted of fusiform cells with dilated rough endoplasmic-reticulum cisternae and irregular cytoplasmic projections that were suggestive of active fibroblasts. No structures suggestive of an epithelial origin or of advanced mesenchymal differentiation were recognized. These observations are consistent with the notion that the pseudosarcomatous stroma represents a reactive process that is probably related to the growth of the epithelial neoplasm. Given the differences in behavior and prognosis between carcinomas with pseudosarcomatous stroma and true carcinosarcomas, efforts at separation of these entities are warranted.

A 25-year-old woman had a malignant ovarian tumor with two distinct tumor patterns: pseudomucinous cystadenocarcinoma and malignant giant cell tumor of bone. One area of the tumor had a lining of tall columnar epithelium with abundant mucin production; however, another area of the same tumor had a number of large multinucleated giant cells that resembled osteoclasts, intermingled with mononuclear stromal cells. There was no blending of the two tumor patterns. Mitoses were frequent in both areas. A probable histogenesis of the tumor from a malignant teratoma is suggested.