[Induction of differentiation of human leukemia cells].

Human myeloid leukemia cells do not differentiate into functional end-cells but remain in the proliferation pool. Human cell lines can serve as model for hematopoietic cells arrested at different stages of myeloid differentiation and helps to dissect the cellular and molecular events involved in leukemogenesis. Furthermore, several agents have been identified as inducers of differentiation of leukemia cells.

1,25-Dihydroxyvitamin D3 receptor RNA: expression in hematopoietic cells.

1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] induces differentiation and inhibits proliferation of myeloid leukemic cells from various lines and patients; these effects are probably mediated through the 1,25(OH)2D3 receptor. Little is known of expression of 1,25(OH)2D3 receptor RNA in hematopoietic cells. We examined the expression and modulation of expression of 1,25(OH)2D3 receptor RNA in various proliferating and nonproliferating hematopoietic cells.

Application of the avidin-biotin-peroxidase complex technique for ultraimmunocytochemical characterization of leukemic cells.

For simultaneous demonstration of cellular ultrastructure, myeloperoxidase activity, and presence of a membrane-bound antigen in a given blood cell, we examined three different fixatives: periodate-lysine-paraformaldehyde (PLP) and paraformaldehyde and glutaraldehyde for their applicability to preembedding electron microscopic immunocytochemistry using monoclonal antibodies and the avidin-biotin-peroxidase complex (ABC) technique. This procedure was examined in samples from 3 normal volunteers and 29 patients with acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), lymphosarcoma cell leukemia (LSCL), blastic phase of chronic myelogenous leukemia (CML-BC), or other unclassified leukemias. PLP fixation preserved the immunoreactivity of surface glycoproteins as well as immunoglobulins to the most satisfactory extent.

Expression of retinoic acid receptor mRNA in hematopoietic cells.

Retinoic acid (RA) has profound effects upon the proliferation and differentiation of many hematopoietic cells. The mechanism by which RA acts is unclear. Recently, several retinoic acid receptors (RAR) have been cloned.

Elevated erythrocyte adenosine deaminase activity in a patient with primary acquired sideroblastic anemia.

We report a case of primary acquired sideroblastic anemia (PASA) associated with elevated erythrocyte adenosine deaminase (ADA) activity. The patient was an 85-year-old Japanese male. Analysis of the peripheral blood revealed pancytopenia, and the bone marrow findings showed marked ringed sideroblasts and chromosomal deletion (46XY, 11q-).

[Clinicopathological studies on disseminated carcinomatosis of the bone marrow occurring through metastasis of gastric carcinoma].

Five cases of gastric carcinoma (one woman) were investigated. The average age of the patients was 44 and the clinical manifestation were lumbago, melena and fatigue. Two cases were Borrmann III, and other were Borrmann IV, IIc and IIc advanced, respectively.

[A case of primary adenosquamous carcinoma of the stomach preoperatively diagnosed by endoscopic biopsy].

A 53-year-old complained of upper abdominal pain. A diagnosis of Borrmann III type gastric cancer in the posterior part of the corpus region was made by X-ray and endoscopy, and primary adenosquamous carcinoma was preoperatively diagnosed by endoscopic biopsy. Subtotal gastrectomy was performed.

[A case of multicentric early carcinoma of the stomach--preoperative diagnosis].

A 59-year-old man was admitted complaining of substernal pain and anorexia. Upper GI series revealed a benign gastric ulcer in the posterior wall, and gastrofiberscopy was done. Besides the benign lesion, two early carcinomas of type IIc were found.