Biomedical subjects

H Tsurumi

Publications and source records attributed to H Tsurumi.

58 records · Page 4Linked to original sources

PubMed1991

[Acute megakaryoblastic leukemia with leukemia cutis, meningeal leukemia, and myelofibrosis].

A 64-year-old man was admitted to our hospital with leukopenia. On admission, leukocyte count in the peripheral blood was 1,600/microliters, containing 24.5% blasts of lymphoid appearance, which were negative for myeloperoxidase. A bone marrow aspiration showed hypoplasia with increased blasts (31.6%). The blasts were ultrastructurally positive for platelet peroxidase (PPO) and positive for platelet membrane glycoprotein IIb/IIIa complex. A diagnosis of acute megakaryoblastic leukemia was made. Chemotherapy with behenoyl-ara C (BH-AC) (150 mg/day) was transiently effective. However, after three months, numerous nodules without itching appeared over the entire body, particularly on the anterior chest. A biopsy of the skin lesion revealed a diffuse fibrosis with infiltrations of the blasts. Bone marrow aspirations were dry tap, and a bone marrow biopsy showed marked myelofibrosis. Then, severe headache, vomiting, and loss of consciousness developed, and a lumbar puncture revealed infiltrations of blasts. Although methotrexate was intrathecally injected, he died due to the respiratory failure. As far as we know, a case of acute megakaryoblastic leukemia with leukemia cutis and meningeal leukemia is quite rare. In addition, it is interesting that megakaryoblastic leukemia was accompanied with both the fibrosis of skin and the myelofibrosis.

Humans↗

PubMed1990

Polyethylene glycol modification of the monoclonal antibody A7 enhances its tumor localization.

The F(ab')2 fragment of murine monoclonal antibody A7 was covalently bonded to polyethylene glycol (PEG, molecular weight: 5000) and the conjugate was compared to the parent F(ab')2 fragment by in vitro and in vivo studies. PEG-conjugated antibody fragment retained its antigen-binding activity in a competitive radioimmunoassay. The conjugate had a longer half-life and showed increased accumulation in tumors. Although the tumor: blood ratio for parent F(ab')2 fragment was higher than that for the conjugate, it showed higher value than whole MAb A7. The tissue: blood ratios were kept low with the conjugate, indicating that the conjugate was uptaken to normal organ with lesser extent, as compared with parent F(ab')2 fragment. Our findings indicate that this PEG-conjugated F(ab')2 fragment could be a promising carrier for use in targeting cancer chemotherapy.

Animals↗

PubMed1990

Binding, internalization and the cytotoxicity of monoclonal antibody A7-neocarzinostatin conjugates (A7-NCS) in target cells.

To study the mechanism of action of the monoclonal antibody A7-neocarzinostatin conjugates (A7-NCS), the internalization of the antibody and its conjugate into target cells was examined. The incubation of radiolabeled A7 and A7-NCS with target cells revealed that both were taken up by target cells in a time dependent fashion. The immunocytochemical study using anti-NCS also revealed the intracellular localization of the conjugates. The cytotoxicity of the conjugate was markedly reduced when the binding sites were occupied by an excess of antibody on the cell surface. These results showed that A7-NCS was internalized into target cells and that its cytotoxicity was mediated through specific binding and internalization.

Animals↗

PubMed1986

Method for processing leukocyte- and platelet-poor red cells in closed bags.

If leukocyte- and platelet-poor red cells have been processed and stored in closed bags, their delivery, especially on holidays, will be easy. The modified warm-centrifuge method was applied to a quadruple bag prepared for such purpose. Red cells were processed in the first bag by the centrifugation of whole blood. The supernatant plasma was transferred to the second bag. A phosphate buffer in the third bag was introduced into red cells and diluted red cells were then incubated at 37 degrees C for 1 h in an inverted position. After centrifugation, the red cell phase below the buffy coat layer was isolated using a Biotest separation apparatus and stored in the fourth bag (containing a preservative with adenine, phosphate, glucose and 0.9% NaCl solution) for 28 days at 4 degrees C. Ninety-eight percent of the leukocyte and 97% of platelets in whole blood unit were removed with a red cell recovery of 86%. Biochemical changes in stored red cells were similar to those of conventional buffy coat-removed red cells suspended in the same preservative, except for rapid decreases in 2,3-diphosphoglycerate levels. Since processing buffy coat-removed red cells containing few leukocytes and platelets with the present method was simple and these units might be stored for over 14 days with minimum cell damage, we suggest that the present method is useful way of processing leukocyte- and platelet-poor red cells in blood centers.

Adenosine Triphosphate↗