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Biomedical subjects

T Kanoh

Publications and source records attributed to T Kanoh.

At least 271 records · Page 15Linked to original sources
PubMed1982

Subcellular localization of H2O2 production in human neutrophils stimulated with particles and an effect of cytochalasin-B on the cells.

The ultrastructural localization of H2O2 production in suspended polymorphonuclear leukocytes (PMN) stimulated with particles was studied using CeCl3 technique. PMN stimulated with opsonized zymosan or polystylene latex with or without IgG were incubated in 0.1 M Tris-maleate buffer with 1 mM CeCl3 and 10 mM aminotriazole. Cells were then fixed and embedded in a resin for electron microscopy. The reaction product of cerium perhydroxide was observed on the phagosomal membranes and on the areas of the plasma membrane engulfing the particles. Catalase or ferricytochrome-c decreased the deposits. p-Benzoquinone (O2- scavenger) inhibited the formation of the deposits, but KCN or NaN3 enhanced it. Pretreatment with p-diazobenzenesulfonic acid inhibited the reaction. In some PMN pretreated with cytochalasin-B, cellular aggregation was observed. The H2O2 production in these cells were observed on the membrane adherent to the particles and on the contact surface of the membrane of adjoining PMN. The plasma membrane was damaged and the electron-dense product was diffused into the cytoplasm. These results clearly show that H2O2 production is initiated at the area of the plasma membrane adherent to the particles and that H2O2 is released before the completion of phagocytosis.

Cell Aggregation↗
PubMed1982

Subcellular localization of hydrogen peroxide production in human polymorphonuclear leukocytes stimulated with lectins, phorbol myristate acetate, and digitonin: an electron microscopic study using CeCl3.

The ultrastructural H2O2-producing site in human polymorphonuclear leukocytes (PMN) stimulated with soluble stimuli was studied using a CeCl3-technique. CeLlular aggregation and formation of small vacuoles were observed when PMN were stimulated with 100 microgram/ml concanavalin-A, 1 mg/ml phytohemagglutinin, or 100 microgram/ml wheat germ agglutinin for 10 min at 37 degrees C. Electron-dense deposits formed from the reaction of H2O2 and CeCl3 were observed on the contact surface of the plasma membrane of aggregated PMN stimulated with lectins. Treatment with 5 microgram/ml cytochalasin-B before lectin-stimulation induced an enhanced formation of vacuoles, degranuLation, rounding of the contour, cellular aggregation, and enhancement of the deposits. Phorbol myristate acetate (PMA; 100 ng/ml) induced strong leukocyte aggregation, the formation of multiple huge vacuoles, degranulation, and H2O2 production at almost all of the contact surface between adjoining PMN and between PMN and erythrocytes, mononuclear cells, or thrombocytes. In PMN stimulated with digitonin (B microgram/ml), vacuolar formation, degranulation, multiple projections on the surface, and H2O2 production on the whole surface membrane were demonstrated. It is shown that cellular aggregation and cell-to-cell contact have an important role in the induction of O2- production induced by lectins or PMA and that O2- production induced by the detergent is not dependent on leukocyte aggregation.

Cell Communication↗
PubMed1981

Primary leptomeningeal melanoma with epipharyngeal invasion.

A case of primary leptomeningeal malignant melanoma in a 45-year-old woman is reported. The tumour was located at the basal aspect of the brain with a larger aggregation in the left parasellar and cerebello-pontine angle regions. The tumour showed not only spinal meningeal dissemination but also infiltration into the petrous bone and along the trigeminal nerve till it reached the submucosal tissue of epipharynx. There are a few reported cases of primary leptomeningeal melanoma which invaded areas outside the central nervous system.

Arachnoid↗
PubMed1981

Adenosine deaminase and ecto-5'-nucleotidase activities in various leukemias with special reference to blast crisis: significance of ecto-5'-nucleotidase in lymphoid blast crisis of chronic myeloid leukemia.

Adenosine deaminase (ADA) and ecto-5'-nucleotidase (5'-N) activities were examined in peripheral leukocytes from patients with leukemias, including nine patients with chronic myeloid leukemia (CML) in blast crisis. Four of none cases of CML in blast crisis were myeloid and the remaining lymphoid morphologically. The diagnosis of CML in lymphoid blast crisis was further contributed by the measurement of terminal deoxynucleotidyl transferase (TdT) activity. In all four cases of lymphoid blast crisis and one of myeloid blast crisis, leukemia cells had high 5'-N activity, while there was a little or no detectable activity in those from four cases of myeloid blast crisis and all of CML in chronic phase. ADA activity was high in seven of nine patients with blast crisis. Taken together, leukemia cells from two cases of lymphoid blast crisis had high ADA and 5'-N activities comparable to those in acute lymphocytic leukemia (ALL) cells. In contrast, the enzyme activities of leukemia cells from all but one patient in myeloid blast crisis were in a range similar to acute myeloid leukemia cells. The implications of these findings are as follows: (1) 5'-N may be used as a new biochemical marker of CML in lymphoid blast crisis. (2) Some lymphoid cells of CML in blast crisis have high ADA, 5'-N, and TdT activities and thus are very similar to ALL cells.

5'-Nucleotidase↗
PubMed1981

J chain synthesis in lymphocytes from patients with selective IgA deficiency.

J chain synthesis was investigated by in vitro pokeweed mitogen (PWM) stimulated peripheral blood lymphocyte (PBL) cultures in eight patients with selective IgA deficiency and compared with that of normal persons. In normals, all IgM-containing cells always had the J chain but only in a portion of IgG- and IgA-containing cells was J chain detectable. The percentage of J chain-positive cells amongst IgG or IgA cells increased during culture, reached a peak at days 5-6 or 6-7, respectively, and then decreased. IgA-deficient patients had very few IgA-containing cells and an increased number and percentage of J chain-positive IgG cells, except for one patient, who had a significant number of IgA-containing cells without IgA secretion into the culture supernatants. Measurement of Ig in culture supernatants by radioimmunoassay revealed that lymphocytes from seven patients secreted significantly smaller amounts of IgG and IgM than did the normal controls, in addition to the defect in IgA production. These results suggested the presence of some ontogenetic relationship between J chain-positive IgG cells and the precursors of IgA-producing cells, and some functional immaturity of most IgG-producing clones seen in patients with selective IgA deficiency.

Cells, Cultured↗