Search PubMedSearch

Biomedical subjects

J Tsuchiya

Publications and source records attributed to J Tsuchiya.

At least 19 recordsLinked to original sources

Antioxidant activities of probucol against lipid peroxidations.

The antioxidant activities of probucol were measured in the oxidations of methyl linoleate in homogeneous solution and soybean phosphatidylcholine liposomal membranes and also of low-density lipoproteins. When an excess amount of probucol was reacted with galvinoxyl, the EPR spectrum of galvinoxyl disappeared and a new triplet EPR signal was found: g = 2.0058 and aH(2H) = 0.14 mT. The identical EPR spectrum was observed when probucol was reacted with tert-butoxyl radical generated from di-tert-butylperoxy oxalate. This EPR signal disappeared rapidly when reacted with either alpha-tocopherol or 6-O-palmitoyl-ascorbic acid. Probucol suppressed the free-radical-mediated oxidations of methyl linoleate in hexane and in acetonitrile, in a dose-dependent manner. Its antioxidant activity was 17.5-fold less than that of alpha-tocopherol in hexane. Probucol incorporated into soybean phosphatidylcholine liposomes suppressed its oxidation. The antioxidant activity of probucol was less than that of alpha-tocopherol, but the difference between the two antioxidant activities was smaller in the membranes than in homogeneous solution. Probucol also suppressed the oxidation of low-density lipoprotein. Interestingly, probucol suppressed the oxidation of LDL as efficiently as alpha-tocopherol, implying that physical factors as well as chemical reactivity are important in determining the overall activity of antioxidant in low-density lipoprotein.

Antioxidants

Ten-year survivors with multiple myeloma.

Of 130 Japanese patients with symptomatic multiple myeloma who were treated between 1970 and 1989, nine (6.9%) patients survived for more than 10 years. Younger age, low and intermediate tumour mass, chemotherapy with cyclophosphamide, the disappearance of myeloma protein, and a positive response to retreatment were correlated with long-term survival.

Aged

Prognostic relevance of morphological classification in multiple myeloma.

One hundred and twenty-two patients with multiple myeloma were classified as mature, intermediate, immature, or plasmablastic subtype according to Greipp's criteria. Contrary to Greipp's report, the survival time of plasmablastic myeloma was not significantly shorter than other subtypes, nor was the plasmablastic subtype identified as a poor prognostic factor. The survival time of mature plus intermediate myeloma was significantly longer than that of immature plus plasmablastic myeloma. Between the former and latter, significant differences were found for sex, clinical stage, thrombocytopenia, bone marrow plasmacytosis, renal insufficiency, bone destruction, and response rate to treatment. Therefore, it was suspected that the immature and plasmablastic subtypes were unfavorable prognostic factors in patients with multiple myeloma.

Aged

Agranulocytosis during treatment with fluconazole.

Fluconazole, a new effective triazole antifungal agent, has been reported to cause fewer adverse reactions than amphotericin B. A patient who was diagnosed as having agranulocytosis and thrombocytopenia after treatment with fluconazole was investigated and recovered after withdrawal of the antifungal therapy. This case suggests the need for careful haematological observation during the treatment with fluconazole.

Adult

A long-term survivor with malignant thymoma accompanied with pure red cell aplasia.

A 56-year-old woman with malignant thymoma lived for 19 years after diagnosis and died of superior vena cava syndrome. An autopsy showed invasion of the thymoma to the right lung and metastasis to the left lung. The pathologic diagnosis was epithelial thymoma (spindle cell dominant) accompanied with pure red cell aplasia (PRCA). However, this was well controlled with steroid therapy. She was the longest survivor with malignant thymoma at this time. Her long-term survival may be the result of good control of the PRCA.

Female

Hematopoietic progenitor cells in a patient with myeloid metaplasia without myelofibrosis.

A rare case of myeloid metaplasia without myelofibrosis is presented. Findings that the increase in blood megakaryocyte progenitor cells was not as prominent as the increase in granulocyte-monocyte and erythroid progenitor cells, and that the increase in bone marrow megakaryocytes was only slight might explain the absence of bone marrow fibrosis in this case. However, it is not clear whether the disease is a subtype or merely an early stage of myelofibrosis with myeloid metaplasia.

Aged

Three cases of multiple myeloma developing into melphalan-related chronic myelomonocytic leukemia.

From 1980 to 1987, three cases of chronic myelomonocytic leukemia (CMML) were encountered among 68 cases of multiple myeloma who survived more than three years from the diagnosis. The incidence (4.8%) of secondary myelodysplastic syndrome (MDS) is almost identical to previous reports, but case reports of chronic myelomonocytic leukemia were rare. In Japan, there are few reports of multiple myeloma patients who later developed secondary MDS or acute myelogenous leukemia (AML). In our cases, none of the 31 patients treated with cyclophosphamide developed secondary MDS, while three of 37 patients treated with melphalan developed CMML. This difference is not statistically significant.

Aged

A patient with primary plasma cell leukemia accompanied by an extensive polypoid infiltration of the gastrointestinal tract.

A 37-year-old male presented with primary plasma cell leukemia (PCL) with kappa-type Bence Jones proteinuria (BJP) and polyposis of the stomach and colon. His plasma cell leukemia was not preceded by a pre-existing multiple myeloma, and presented the complication of polyposis in both stomach and colon. Biopsy of mucosal lesions revealed marked accumulation of atypical plasma cells with positive cytoplasmic kappa-chain. No amyloidosis was present. His disease responded remarkably well to intermittent melphalan and prednisolone. This case represents an uncommon combination of primary plasma cell leukemia and polypoid gastrointestinal lesions with plasma cell infiltration.

Adult

Prognostic aspects of aplastic anemia in pregnancy. Experience on six cases and review of the literature.

Our resent experience on six cases of aplastic anemia complicated with pregnancy is described. In addition, 43 similar cases were collected from the literature and reviewed to analyze some prognostic aspects of this relatively rare but potentially serious complication. Clinical and hematological data were treated to extract some clinically meaningful factors in relation to the success and failure of pregnancy. Among initial hematological parameters, no significant difference was found between successful and unsuccessful cases with an exception of hemoglobin concentration. The patients diagnosed as aplastic anemia prior to conception demonstrated an better outcome of pregnancy as well as survival rate of mother when compared with those diagnosed during pregnancy. Mortality has apparently improved after the late 1950's. Success rate of pregnancy before 1958 was 21%, while it was 67% and 71% in the era of 1959-1969 and after 1970, respectively. However, hemorrhage and infection remained to be two major causes of maternal death in both eras. Based on these observations, the currently recommendable attitude to this complication is discussed.

Adult

Erythroblast kinetics in pernicious anaemia, erythroleukaemia and sideroblastic anaemia.

DNA synthesis time (Ts) and 3H-thymidine labelling index (TLI) of erythroblasts have been determined in 25 patients with various types of haematologic disorders using in vitro double labelling method. No remarkable differences in both Ts and TLI were noted between haematologically normal subjects and patients with increased effective erythropoiesis (haemolytic anaemias), suggesting that the cell cycle time is not principally altered under the augmented erythropoiesis. In pernicious anaemia, Ts of basophilic erythroblasts was significantly shortened and TLI was elevated above normal. Normalization of erythropoiesis by vitamin B12 was associated with a transient increase of TLI in polychromatic erythroblasts, which was interpreted to reflect prevention of intramedullary premature death of basophilic megaloblasts. Erythroleukaemia showed a markedly prolonged Ts and lowered TLI indicating the presence of cells with prolonged cell cycle time. These findings contrasted to that of pernicious anaemia despite certain morphological as well as functional similarities. In idiopathic sideroblastic anaemia, prolongation of Ts was observed to a similar extent as erythroleukaemia, while TLI remained almost normal. In 2 cases with suspected erythroleukaemia presenting an intermediate clinical picture between erythroleukaemia and sideroblastic anaemia, Ts of basophilic erythroblasts was found to be prolonged along with modestly lowered TLI.

Anemia, Pernicious