Search PubMed⌕ Search

Biomedical subjects

N Tominaga

Publications and source records attributed to N Tominaga.

At least 19 recordsLinked to original sources
PubMed1992

Growth inhibition of RPMI 8226 human myeloma cells by peripheral blood lymphocytes.

To clarify the components of cellular immunity responsible for defense against the clonal development of myeloma cells, we tested the capacity of human peripheral blood lymphocytes (PBLs) to inhibit the growth of 3 human myeloma cell lines (RPMI 8226, OPM-1, and OPM-2). RPMI 8226 was found to be sensitive to PBLs, showing almost complete growth arrest when cultured with PBLs for 72 h. Inhibition of the growth of RPMI 8226 cells required direct cell-to-cell contact but not presensitization of the PBLs to the target cells, and did not depend on the generation of soluble factors. CD3+, CD4-, CD8- and CD16- cells were found to be the major subset contributing to inhibition of the growth of RPMI 8226 cells, and this growth inhibition was cytostatic rather than cytotoxic. These characteristics distinguished it from growth inhibition mediated by the natural killer system. Impaired PBL-mediated growth inhibition of RPMI 8226 cells was found in patients with various hematologic diseases, including myeloma. It therefore appears that the CD3+, CD4-, CD8- and CD16- cell subset might be involved in tumor immunity in myeloma.

Antibodies, Monoclonal↗
PubMed1992

Stimulatory effect of vanadate on 3',5'-cyclic guanosine monophosphate-inhibited low Michaelis-Menten constant 3',5'-cyclic adenosine monophosphate phosphodiesterase activity in isolated rat fat pads.

When isolated rat fat pads were incubated with vanadate, the low Michaelis-Menten constant (Km) cAMP phosphodiesterase (PDE) activity in the microsomal fraction was increased in a time- and dose-dependent manner with vanadate. 3',5'-Cyclic GMP inhibited the vanadate-stimulated PDE activity with similar profile to the insulin-stimulated one. The stimulatory effect of vanadate was inhibited by inhibitors of tyrosine kinases such as amiloride, biochanin A, and genistein to various extents. Vanadate and insulin both showed the full effect in the absence of either K+, N+, or Ca2+ in the medium, while preincubation of the fat pads with a chelator of intracellular Ca2+ inhibited the vanadate action in a dose-dependent manner. The insulin action was not inhibited by it at tested concentrations. These results suggest that the vanadate action, in contrast to the insulin one, is dependent on the intracellular level of Ca2+. Preincubation of the fat pads with inhibitors of protein kinase C such as 1-(5-isoquinoline sulfonyl)-2-methylpiperazine (H-7) and staurosporine inhibited, in part, the vanadate action but did not inhibit the insulin one. Furthermore, vanadate increased the protein kinase C activity in fat pads but insulin did not increase. H-7 and amiloride showed a significant inhibition of stimulation of protein kinase C activity by vanadate. These results suggest that vanadate stimulates, in part, the 3',5'-cyclic GMP-inhibited low Km cAMP PDE activity in the microsomal fraction of fat pads through the activation of tyrosine kinase and protein kinase C-mediated processes.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Anticoagulant action of vanadate.

Sodium orthovanadate (vanadate) prolonged the clotting time of normal human plasma in a dose-dependent manner. The prolongation of clotting time by vanadate linearly decreased with an increase in the concentration of amiloride. Vanadate also was completely additive to prolongation by heparin. When factor Xa or thrombin was incubated with vanadate, the amidolytic activity of each decreased in a dose-dependent manner with vanadate. Amiloride protected the decrease of amidolytic activity of both factor Xa and thrombin by vanadate. The amidolytic activity of trypsin also was inhibited by vanadate, but that of alpha-chymotrypsin was not inhibited, suggesting that vanadate preferentially inhibits the amidolytic activity of trypsin and trypsin-like enzymes. These results show that vanadate prolongs the clotting time of plasma through mechanisms involving in part the inhibition of the activity of both factor Xa and thrombin.

Amino Acid Sequence↗
PubMed1992

Inhibition of increasing effect of vanadate on glycogen content and lipoprotein lipase activity in fat pads by 5-N,N-hexamethylene amiloride.

Sodium orthovanadate (vanadate) increased the glycogen content in isolated rat fat pads in a dose-dependent manner up to 2 mM. Biochanin A, a specific inhibitor of tyrosine kinases, inhibited the increasing effect of vanadate or insulin on both glycogen content and lipoprotein lipase (LPL) activity in fat pads. The increasing effect of vanadate on glycogen content was not decreased by the replacement of Na+ with choline ion in the incubation medium. 5-N,N-Hexamethylene amiloride, a potent inhibitor of the Na+/H+ exchange system, showed a 50%-inhibition of the vanadate-increased LPL activity and glycogen content at 25 and 80 microM, respectively, suggesting that mechanisms of the inhibition differ in part between the vanadate actions. Furthermore, a similar inhibitory profile of the vanadate-increased glycogen content was observed with incubation in the presence of absence of Na+ in the medium. These results suggest that the activation of the Na+/H+ exchange system by vanadate is not involved in an increase in the glycogen content in fat pads.

Adipose Tissue↗
PubMed1992

Marked increase of CD57+CD16- cells in long-term survivors of graft-versus-host disease after allogeneic bone marrow transplantation.

We have evaluated long-term serial changes in the immunological state from soon after allogeneic bone marrow transplantation (BMT) In 44, mainly leukemia patients with respect to changes in lymphocyte surface markers. Absolute numbers of cluster designation (CD)2+, CD20+ and human lymphocyte antigen-DR+ (HLA-DR+) cells recovered to within their normal ranges three months, one year and two years, respectively, after BMT. The reversal of the CD4+: CD8+ ratio persisted for five years or more but returned to normal after six years. CD57+CD16- cells were markedly increased from three mo up to a maximum of five years after transplantation; they were increased between three and six months after transplantation irrespective of graft-versus-host disease (GVHD), but changes after one year or more differed among patients without GVHD, with acute GVHD, with acute and chronic GVHD or with chronic GVHD. Absolute numbers of CD57+CD16- cells tended gradually to return to normal after one year or more in the group without GVHD but only after six years in patients in the other three GVHD groups.

Adolescent↗
PubMed1991

Improved determination of the bisphosphonate pamidronate disodium in plasma and urine by pre-column derivatization with fluorescamine, high-performance liquid chromatography and fluorescence detection.

An improved method for the determination of 1-hydroxy-3-aminopropylidene-1,1-bisphosphonate (pamidronate) in human urine and plasma is described. The procedure is based on a co-precipitation of the bisphosphonates (pamidronate and 6-amino-1-hydroxypentilidene-bisphosphonate, used as internal standard) with calcium phosphate. After centrifugation the precipitate is redissolved in hydrochloric acid, followed by a second precipitation. Then the bisphosphonates are dissolved in ethylenediaminetetraacetic acid, derivatized with fluorescamine, and separated by high-performance liquid chromatography. Using fluorescence detection, the limit of quantitation for pamidronate was 0.8 mumol/l in plasma and 0.7 mumol/l in urine.

Chromatography, High Pressure Liquid↗
PubMed1991

Immunologic and immunohistochemical studies on chronic lymphocytic thyroiditis with or without thyroid lymphoma.

The local immunologic phenomena in the thyroid gland of 16 patients with chronic lymphocytic thyroiditis (CLTH) were investigated; 5 of these cases were associated with thyroid non-Hodgkin's lymphomas (NHL). All patients were admitted because of struma, growing slowly in patients with CLTH alone and rapidly in those with associated thyroid NHL. CLTH was confirmed by histologic findings, including the presence of lymphoid follicles or thyroid autoantibodies in the serum in all 16 patients. Immunologic study revealed that all thyroid NHL were of the B cell type. Surface maker study of suspended cells showed that the percentages of E-rosette-forming cells in patient with CLTH and thyroid NHL (38.0 +/- 10.0%) and in patients with CLTH alone (45.0 +/- 11.9%) were between those of B cell NHL of lymph node and B cell hyperplasia reported by others. Immunohistochemical studies confirmed the reactive nature of lymphoid follicles. Subset distribution of T and B lymphocytes in patients with CLTH and thyroid NHL markedly contrasted with that in patients with CLTH alone: an increased ration of CD8+ cells (suppressor/cytotoxic cell) to CD4+ cells (helper/inducer cell). There was a marked increase in the number of immunosuppressive acidic-protein(IAP)-containing macrophages in the thyroid lesion and serum IAP level in patients with thyroid NHL. These findings provide evidence of a difference in the local immunologic conditions in CLTH alone compared to CLTH complicated by thyroid NHL.

Adult↗
PubMed1991

A putative mouse oocyte maturation inhibitory protein from urine of pregnant women: N-terminal sequence homology with human nonsecretory ribonuclease.

A putative mouse oocyte maturation inhibitory protein was purified from a urine preparation from pregnant women by Sephadex G-100 gel filtration and reverse-phase chromatography on the basis of inhibitory activity of polar body formation of denuded mouse oocytes in culture. Amino terminal sequence analyses showed that residues 5 to 15 of this protein were identical to residues 1 to 11 of human nonsecretory ribonuclease. Furthermore, residues 1 to 4 of this protein were identical to residues -4 to -1, corresponding to part of a signal peptide region of eosinophil-derived neurotoxin, whose mature sequence is identical to nonsecretory ribonuclease. These results indicate that the protein purified as a putative mouse oocyte maturation inhibitory protein from the urine of pregnant women may be a product of an peculiar processing of a nonsecretory ribonuclease precursor.

Amino Acid Sequence↗
PubMed1991

Clinical effect of granulocyte colony-stimulating factor on neutrophils and leukemic cells in myelogenous leukemia: analysis.

Clinical experiences with recombinant granulocyte colony-stimulating factor (rhG-CSF) in 13 acute (AML) and four chronic (CML) myelogenous leukemia patients are reported. Sixteen patients received rhG-CSF in support of treatment for life threatening infections and one CML patient in support of induction chemotherapy. After their first induction chemotherapy, six out of eight AML patients showed a rapid increase of neutrophils, recovered from infections and achieved complete remission (CR). One patient, in whom both neutrophils and blasts had increased during rhG-CSF administration, achieved CR through the next administration of chemotherapy (CR rate 87.5%). The last of the eight AML patients showed no increase of neutrophils, and died of interstitial pneumonitis. Two of five AML patients who received rhG-CSF after reinduction chemotherapy for relapsed or refractory leukemia achieved CR, a rate of 40%. In one of the two, the administration of rhG-CSF prior to induction chemotherapy seemed advantageous in achieving CR. During rhG-CSF administration, an increase of blastic cells in peripheral blood was observed in four out of all 13 AML patients. One of three CML patients, with a lymphoid crisis, showed an increase only of neutrophils, and recovered from infection. The other two showed increases of both neutrophils and blasts. One patient with CML in blastic crisis, undergoing induction chemotherapy with rhG-CSF administration, returned to the chronic phase. These clinical experiences suggest rhG-CSF to be effective in supporting infection therapy and in possibly enhancing the sensitivity of myelogenous leukemic blasts to antileukemic agents.

Adolescent↗
PubMed1991

[The analysis of leukemic relapse after allogeneic bone marrow transplantation].

This report presents the analysis of leukemic relapse of 52 patients who received allogeneic bone marrow transplantation between July 1984 and May 1990. Conditioning regimen consisted of TBI + CY and GVHD prophylaxis consisted of cyclosporin-A and methotrexate. The relapse ratios of chronic myelogenous leukemia (CML) (21 in chronic phase, 1 in accelerated phase, 1 in blastic crisis), acute nonlymphocytic leukemia (ANLL) (all 17 in 1st CR), acute lymphocytic leukemia (ALL) (all 12 in 1st CR) were 13%, 18%, 25%, respectively, and 3 year disease free survival (DFS) was as follows, CML 68%, ANLL 72%, ALL 49%. Regarding acute GVHD grading and chronic GVHD presence, 3 year DFS was as follows, acute GVHD 0 degree: 59%, I degree: 78%, II degree-IV degree: 53%, chronic GVHD (+): 82% GVHD (-): 77%. In our center leukemic relapse has been the major cause of death after BMT since 1984. Among 9 relapsed cases, one recurred more than 3 years after BMT, and another one got recurrent leukemia of donor origin.

Adolescent↗
PubMed1991

[Early phase II study of MST-16 (sobuzoxane) on malignant lymphoma].

Early phase II study of MST-16[4,4-(1,2-ethanediyl) bis (1-isobutoxycarbonyloxy-methyl-2, 6-piperazinedione], a derivative of ICRF-154, on malignant lymphoma was conducted by multi-institutional cooperative group. MST-16 was administered orally at doses of 1,600 mg/body/day for 5 days or 1,200 mg/body/day for 10-14 days, mainly. The number of registered and evaluated patients were 29 and 28, respectively (Hodgkin's disease 3 patients and non-Hodgkin lymphoma 25). Twenty-seven of 28 patients had received prior chemotherapy and/or radiation therapy. Of 28 evaluable patients, overall response rate (CR + PR) was 32.1%. In high-dose administration group, the response rate was not significantly high. The response rate seemed to be high in patients who were treated repeatedly (number of courses greater than 3). Major side effects observed were myelosuppression and gastro-intestinal disorders which were reversible in a rest period. Myelosuppression seemed to be severe in high-dose administration group. This study indicated that MST-16 was a useful agent against malignant lymphoma including primary resistant or relapsed patients, and that the recommended regimen for a late phase II study was considered to be 1,600-2,400 mg/body/day for 5-7 days repeatedly with a pause of several days. Furthermore, the study should be considered at the dose of 3,200 mg/body because half cases administered at this dose showed some response.

Adult↗
PubMed1991

Intracellular immature subunits of human chorionic gonadotropin in first trimester placental cells: purification and characterization.

As we previously reported [Sakakibara et al. (1986) Biochem. Biophys. Res. Commun. 137, 443-452; and Tominaga et al. (1989) J. Biochem. 105, 992-997], subunits of human chorionic gonadotropin (hCG) containing immature N-linked sugar chains (immature subunits), i.e., the 21 kDa form of alpha-subunit and the 23 and 19 kDa forms of beta-subunit, are present predominantly in first trimester placental cells. The molecular mass of intracellular hCG consisting of these subunits, based on gel filtration, was approximately 200 kDa, suggesting homo- or hetero-oligomerization of intracellular hCG. In the present study, we purified the 21 kDa form of alpha-subunit as well as the 23 and 19 kDa forms of beta-subunit from fresh normal first trimester placental tissues by gel filtration and reverse-phase high-performance liquid chromatography. Purified subunits were hydrolyzed (with a decrease in their molecular weighs) by endoglycosidase H and alpha-mannosidase but not by sialidase or sialidase followed by O-glycanase, indicating that those forms have presumably only high-mannose-type N-linked sugar chains but not O-linked sugar chains of the type present in mature beta-subunit. Fifteen cycles of Edman degradation of the purified forms of the subunits were performed. Only one phenylthiohydantoin amino acid, which was the same amino acid as in the urinary beta-subunit, was detected at each step for the mixture of 23 and 19 kDa forms of beta-subunit, indicating that the protein backbones of both forms are identical to each other as well as to the urinary beta-subunit.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

Establishment and characterization of a new human B-cell line (ONHL-1) from non-Hodgkin's lymphoma: constant expression of bcl-2 gene during mitogen-induced growth inhibition.

A new B-cell line (ONHL-1) was established from non-Hodgkin's lymphoma. ONHL-1 was free from Epstein-Barr virus nuclear antigen and expressed CD20, CD24, and slg (mu, delta, gamma and kappa), thus being equivalent to the mature B-cell stage. Chromosome analysis revealed a markedly abnormal pattern including 14q+ and 6q-. In accordance with the positive expression of surface kappa light chains, one of the kappa genes was found to be rearranged. However, rearrangement of the lambda locus was also detected, contrary to the supposed hierarchy for the rearrangement of the light-chain genes. Further, the rearranged fragments of the JH, C lambda, and bcl-2 genes were of the same size in the EcoRI and HindIII digests on the same filter. This may suggest that the bcl-2 gene is juxtaposed with the JH and C lambda locus. The proliferation of ONHL-I was inhibited by adding Staphylococcus aureus Cowan 1 or 12-O-tetradecanoyl-phorbol-13-acetate. During this growth inhibition, the expression of c-myc decreased, while that of bcl-2 mRNA remained steady. This result suggests that not the bcl-2 gene but other oncogenes, such as c-myc, play a key role in the proliferation of ONHL-1. This agrees with the hypothesis that the bcl-2 gene is not concerned with aggressive proliferation but with cell survival. This new cell line will therefore be of value in studying the differentiation and tumorigenesis of B cells.

Cell Division↗
PubMed1990

Demonstration of high-affinity interleukin-2 receptors on B-chronic lymphocytic leukemia cells: functional and structural characterization.

Functional and structural characteristics of interleukin 2 (IL-2) receptors on B-cell chronic lymphocytic leukemia (B-CLL) cells were analyzed by a proliferation assay, IL-2 binding assay and cross-linking study. In the 3H-thymidine incorporation assay, purified B-CLL cells from four out of sixteen cases, in which the percentage of Tac antigen (Tac Ag) positive cells in peripheral blood lymphocytes ranged from 0 to 48.8%, responded to IL-2 (100 U/ml) after both 3- and 6-day incubation. No relationship was found between the responsiveness to IL-2 and the percentage of Tac Ag positive cells. In the radiolabeled IL-2 binding assay, however, B-CLL cells from all seven cases examined, including three cases with mitogenic response to IL-2 and four cases without mitogenic response, were shown to have both high- and low-affinity receptors. The number of high- and low-affinity receptors per cell ranged from 29-186 and from 420 to 1,800, respectively. Furthermore, with the affinity cross-linking method p55 (Tac Ag) and p70/75 were found even in cases without mitogenic response in their B-CLL cells. In conclusion, the B-CLL cells so far examined possessed high-affinity IL-2 receptors consisting of p55 and p70/75; nevertheless, this was not sufficient to respond to the mitogenic signal of IL-2.

B-Lymphocytes↗
PubMed1990

Aberrant expression of immunoglobulin light chain isotype in B lymphocytes from patients with monoclonal gammopathies: isotypic discordance and clonal B-cell excess.

A study was made of 29 patients with monoclonal gammopathies to detect aberrations in immunoglobulin (Ig) light chain isotype expression in lymphocytes at various levels of B-cell differentiation, namely, circulating surface Ig positive (SIg+) cells, Ig-secreting cells (plaque forming cells, PFC) and mitogen-induced PFC. By using kappa-lambda analysis, two major phenotypes of aberrant Ig light chain isotype expression were found in circulating B cells at these three levels of differentiation: an absolute increase in B cells bearing the same Ig light chain isotype as that of monoclonal protein (clonal B-cell excess), and a relative decrease in those B cells (isotypic discordance). Isotypic discordance (ID) was found to be essentially negative in patients with monoclonal gammopathy of undetermined significance (MGUS) provided that they were in a stable condition. In myeloma patients, ID was found only in stage I, except for a remission case of stage III (4/7 in stage I, 0/8 in stage II, and 1/6 in stage III). ID was not restricted to a circulating SIg+ cell level but was also demonstrable at a spontaneous or pokeweed mitogen-induced PFC level. However, ID was negative at a PFC level induced by Staphylococcus aureus Cowan I. Clonal B-cell excess (CE) was frequently found in patients with active myeloma but not in stable patients (0/8 in MGUS, 1/7 in stage I, 8/8 in stage II, and 4/6 in stage III). CE was positive not only at a circulating SIg+ cell level but also at a circulating PFC level. Furthermore, patients with CE at a PFC level were found to have a higher proliferating capacity, defined as a percentage labelling index of marrow myeloma cells, than those without CE at a PFC level (P less than 0.02). ID and CE can therefore be considered as useful markers for discriminating between MGUS and myeloma, evaluating the clinical stability and predicting the clinical course.

Antibody-Producing Cells↗
PubMed1990

Effective purification of human chorionic gonadotropin and its subunits from pregnant women's urinary peptides absorbed on reverse-phase resin.

Human chorionic gonadotropin (hCG) was extracted and purified by reverse-phase resin (Sepralyte C8 resin) adsorption and Sephadex G-100 column chromatography from urine of pregnant women. Approximately 15000 IU of hCG was recovered from 1000 ml of urine by C8 resin adsorption. hCG from the gel-filtration step stimulated testosterone production in rat Leydig cells and had a specific activity of approximately 8000 IU/mg, a value which was higher than those of commercial hCGs. Furthermore, hCG purified to near-homogeneity was separated effectively into its subunits by reverse-phase high-performance liquid chromatography using an acetonitrile gradient in the presence of 0.1% trifluoroacetic acid with no special pretreatment for dissociation of subunits. The separated subunits were able to re-associate. The techniques used are simple and may be suitable for not only laboratory but also industrial production of hCG and its subunits.

Animals↗