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Biomedical subjects

T Fukuhara

Publications and source records attributed to T Fukuhara.

At least 109 records · Page 6Linked to original sources
PubMed1988

[Hematopoietic reconstitution in the allogeneic bone marrow chimeric mice].

Hematopoietic reconstitution in the allogeneic chimera is an important issue because its failure causes fatal infection in the host. Although graft-versus-host disease (GVHD) often occurs and is a major obstacle for successful bone marrow transplantation (BMT), it does not always play an unfavorable role in the host. It has been suggested that GVHD may show some effects on the hematopoietic reconstitution. In order to elucidate mechanism of the influence of GVHD on the hematopoiesis, I have studied kinetics of the hematopoietic progenitor cells in the bone marrow chimeric mice and the effects of spleen cells on it using in vitro CFU-GM assay. The number of CFU-GM in the bone marrow obtained from the allogeneic chimeras were reduced in the very early phase after BMT compared to that of syngeneic bone marrow chimeras. After then, the CFU-GM number in the allogeneic chimeras increased rapidly, especially in the chimeras showing a sign of severe GVHD. Addition of spleen cells from syngeneic chimeras to the bone marrow cell cultures showed no influence on the CFU-GM number observed. However, addition of spleen cells from allogeneic chimeras at 14 days after BMT to the bone marrow cells increased the CFU-GM number. By contrast, the chimeric spleen cells at 21 days after BMT decreased the number. These biphasic effects of spleen cells from allogeneic chimeras on the CFU-GM were considered to be mediated by some kinds of colony stimulating and inhibiting factors. Intraperitoneal injections of recombinant granulocyte-colony stimulating factors into bone marrow chimeras increased the number of granulocyte.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Changes of Ca2+-ATPase and cytochrome oxidase activity of myocardial cell under early and late ischemia:--comparison with ultrastructural changes.

Using the histo- and cytochemical technique we assessed the Ca2+-transporting function of mitochondria (Mit) and sarcoplasmic reticulum (SR), and the ATP producing function of Mit in the ischemic myocardial cell of a dog's heart. In comparing ultrastructural ischemic changes, cytochrome oxidase (CO) and Ca2+-ATPase were cytochemically and histochemically measured when the myocardium was subjected to the ischemia of left anterior descending coronary artery occlusion for 15 min, and 60 min. After 15 min of occlusion the ischemic alterations consisted of a wide I band, decreased glycogen (G) and Mit swelling with a slight reduction of matrix density. Although CO activity was not reduced, Ca2+-ATPase had decreased mainly in Mit. Sixty min of ischemia resulted in loss of G, intermyofibrillar edema, marked Mit swelling with loss of matrix density and partial disruption of cristae, and dilatation of SR. Ca2+-ATPase activity was significantly reduced in Mit, SR and myofibrils. Although there was Mit swelling with partial disruption of cristae after 60 min of ischemia, CO activity was found to still exist in the remaining cristae. These findings suggest that intracellular organelle dysfunction progresses in the ischemic myocardial cell at different rates, and that disruption of intracellular Ca2+-homeostasis may occur early in the ischemic state.

Animals↗
PubMed1987

Non-T, non-B acute lymphocytic leukemias: cellular origin based on molecular analyses of immunoglobulin and T-cell alpha- and beta-chain receptor gene rearrangements.

Fifteen non-T, non-B acute lymphocytic leukemia (ALL) cases were investigated for determining cellular origin based on molecular (immunoglobulin and T-cell alpha-receptor (TcR alpha) and T-cell beta-receptor (TcR beta) genes) and immunophenotypical analyses. As defined by monoclonal antibodies, they were classified into 2 groups; 12 cases as common ALL antigen (CALLA)-positive ALL and 3 cases as CALLA-negative ALL. Southern blot analysis revealed that 11 CALLA-positive ALL cases contained rearranged JH gene and 2 of them contained rearranged Jx genes, similar to recent views that most CALLA-positive leukemic cells are neoplastic B-cell precursors. One CALLA-positive ALL case, whose leukemic cells were also Leu-1 positive, showed no rearrangement of JH and TcR beta genes. On the other hand, non-T, non-B CALLA-negative ALL, so called null ALL, consisted of heterogenous groups with regard to lymphocyte differentiation and lineage; one out of 3 null ALL cases may be truely undifferentiated as shown neither JH nor TcR beta gene rearrangement, but other 2 cases showed either JH or TcR beta gene rearrangement. Dual rearrangements of Ig and TcR beta genes occur frequently in 3 out of 15 non-T, non-B ALL cases, but all cases of bigenotype showed no doubly marked profile and retained a completely fidelous immunophenotypic pattern. We further investigated the possibility that analysis of TcR alpha gene may be useful for determining cellular origin of non-T, non-B ALL leukemic cells.

Genotype↗
PubMed1987

Characterization studies of suppressor cells in murine bone marrow chimaeras.

When BALB/c bone marrow cells were transferred to lethally X-irradiated C3H/He mice either intrasplenically (i.s.) or intravenously (i.v.), suppressor cells were detected by means of MLR coculture assays in the spleen of i.s. and i.v. chimaeras. Some but not all of the suppressor cells expressed a Thy 1.2 antigen, indicating that suppressor cells either sensitive or insensitive to anti-Thy 1.2 antibody plus complement treatment were generated in the spleen of i.s. and i.v. chimaeras. According to the examination of Lyt alloantigen expression on suppressor T cells, Lyt 1+2-, Lyt 1-2+, and Lyt 1+2+ suppressor T cells appeared to be present. The culture supernatants from several T-cell clones showed the suppressor activity against alloreactive MLR. Cell surface markers of these clones were composed of Lyt 1+2-, Lyt 1+2+ and Lyt 1-2+. In addition, since Carrageenan treatment abrogated the suppressor activity of plastic dish adherent cells, we conclude that some of them were composed mainly of macrophages.

Animals↗
PubMed1987

[An autopsy case of severe miliary tuberculosis in a patient with acute lymphatic leukemia (ALL)].

A 58-year-old Japanese man being diagnosed as having ALL suffered from continuous fever and dysfunction of the liver and kidneys despite being in a state of haematological remission. Further clinical investigations, however had not been able to find the causes of his condition before his death. The autopsy revealed severe miliary tuberculosis affecting many organs including the heart, lungs, liver, spleen, kidneys, thyroid gland, pancreas, bone marrow, and central nervous system, which is compatible with multiple organ failures. Recent pharmacological advances have increased the usage of many kinds of antineoplastic drugs, and this has resulted in increased chances of opportunistic infections by various microorganisms in the course of treatment. The present case implies the significance of the reactivation of tuberculosis in the secondary immunodeficient syndrome (SIDS).

Humans↗