Curvularia lunata in experimental phaeohyphomycosis.

Curvularia lunata strain SP, isolated from a disseminated human infection, infected normal mice, but three other strains of C. lunata and one each of C. pallescens and C. spicifera did not. The SP strain was recovered in cultures from, and hyphal filaments were observed in, abscesses in the liver and spleen of experimentally infected mice. All strains of Curvularia infected mice treated with 400 rads X-irradiation and 10.0 mg cortisone, but at 400 rads and 5.0 mg only two strains of C. lunata (SP and Ghosh) and C. pallescens and C. spicifera infected mice. At 200 rads and 10.0 mg, C. lunata Sp, C. pallescens and C. spicifera; and at 200 rads and 5.0 mg, only C. lunata SP and C. pallescens caused infection. After X-irradiation (200 or 400 rads) or cortisone (5.0 or 10.0 mg) alone only C. lunata SP caused infections in mice.

T-cell lymphomas of large cell type. A variety of malignant lymphomas: "histiocytic" and mixed lymphocytic-"histiocytic".

Clinical and morphologic features of seven T-cell lymphomas of the large cell type are described. The tumors were grouped into those with irregular (3 cases) and those with round and regular nuclei (4 cases). In both groups, variation in cell size, numerous histiocytes and vessels, and many mitoses were distinguishing features. In only 1 case in the round and regular nucleus group was there relatively little variation in cell size and a paucity of histiocytes. Abundant polyribosomes, long strands of rough endoplasmic reticulum, and lysosomal granules were prominent electron microscopic features in both groups of tumors. The clinical presentations and courses varied considerably, especially in patients with tumors of the round nucleus type. One patient presented initially with chronic lymphocytic leukemia, 1 with Lennert's lymphoma, another with bone marrow infiltration, and a fourth with subcutaneous tumors. Two patients with the round nucleus type are still alive one and a half and two years after the original diagnosis. Two patients died two years after the onset of symptoms. Each of the 3 patients with tumors of the irregular nucleus type had a rapid clinical course and died within ten months.

Immunoblastic sarcoma (histiocytic lymphoma) of the brain with B cell markers. Case report.

A group of central nervous system neoplasms, previously known as reticulum cell sarcoma or microglioma, and recently classified as malignant lymphoma, histiocytic type, not infrequently occur in patients with immunodeficiency, either primary or induced by immunosuppressant drugs. The authors report such a neoplasm in a patient with idiopathic thrombocytopenic purpura immunosuppressed with azathioprine and prednisone. The neoplasm was studied with several immunological techniques and by electron microscopy. The neoplasm had B lymphocyte membrane markers and showed plasmacytic differentiation. These features suggest that it was a tumor of transformed B lymphocytes (immunoblasts).

Hairy cells and macrophages: a comparative study.

Leighton tube cultures of peripheral blood leukocytes and splenic cell suspensions of 11 patients with hairy cell leukemia (leukemic reticuloendotheliosis) were utilized to compare characteristics of hairy cells and macrophages. Light and electron microscopy, both transmission and scanning, as well as cytochemical studies demonstrated several striking similarities to macrophages. They included phagocytosis of red cells, platelets, cellular debris, and latex particles, adherence to glass with development of long pseudopodia and cytoplasmic granules, alpha-naphthyl butyrate esterase activity and diffuse and granular periodic acid-Schiff positivity.