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Biomedical subjects

M Takeshita

Publications and source records attributed to M Takeshita.

At least 19 recordsLinked to original sources
PubMed1996

Spermine suppresses the activation of human neutrophil NADPH oxidase in cell-free and semi-recombinant systems.

Spermine, a cellular polyamine, down-regulates O2- generation in human neutrophils stimulated by receptor-linked agonist [Ogata, Tamura and Takeshita (1992) Biochem. Biophys. Res. Commun. 182, 20-26]. In this study, to elucidate the mechanism for the inhibition, the effect of spermine on cell-free activation of the O2- generating enzyme (NADPH oxidase) was examined. Spermine suppressed the SDS-induced activation of NADPH oxidase in a dose-dependent manner with an IC50 of 18 microM. The inhibition was specific for spermine over its precursor amines, spermidine and putrescine. Spermine did not alter the Km for NADPH or the optimal concentration of SDS for activation. The amine was inhibitory only when added before activation, indicating that it affects the activation process rather than the enzyme's activity. An increased concentration of cytosol partly prevented the inhibition by spermine. In semi-recombinant cell-free system, spermine inhibited the activation of NADPH oxidase as effectively as in the cell-free system (IC50 = 13 microM). Pretreatment of each recombinant cytosolic component with spermine revealed that they (especially p67phox) are sensitive to spermine. These results suggest that spermine interacts with cytosolic component(s) and impairs the assembly of NADPH oxidase.

Cell-Free System↗
PubMed1996

Random suppression of T cells that bear specific T cell receptor V beta sequences in adult T cell leukemia/lymphoma (ATLL) patients at each clinical stage: carrier, smoldering, chronic, and acute.

Human T cell leukemia virus type I (HTLV-I) is associated with adult T cell leukemia/lymphoma (ATLL), which is well known as a T cell malignancy. In order to clarify whether HTLV-I plays a role as a virus-encoded superantigen in the neoplastic process, we examined the TCR V beta families in the peripheral blood at four different clinical stages: carrier, smoldering leukemia, chronic leukemia, and acute leukemia. An increased number of CD4 T cells was found in each of the four clinical stages. However, we found neither uniform specific losses nor uniform clonal expansion of particular TCR V beta gene families in any case from the four clinical stages. However, a suppression of the random TCR V beta families was found. Our data did not therefore directly suggest the existence of a common superantigen model of HTLV-I which induces an increase in CD4 T cells. The random suppression in the TCR V beta repertoire is most likely caused by the influence of HTLV-I neoplastic pathogenesis rather than by virus-encoded superantigens. In the patients with acute leukemia, one or two families of the V beta repertoires were very strongly expressed, while in chronic leukemia, no such repertoire of strong expression was observed. The immunological reaction of the hosts might thus be different between the above described groups.

Acute Disease↗
PubMed1995

Anaplastic large cell lymphomas expressing the novel chimeric protein p80NPM/ALK: a distinct clinicopathologic entity.

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma characterized by the CD30+ large neoplastic cells and sometimes carries a t(2;5)(p23;q35). Recently, we found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in ALCLs with t(2;5). Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene (Morris et al, Science 263:1281, 1994). Meanwhile, the clinicopathologic features of p80-carrying ALCLs have remained unclear. Paraffin sections of 105 cases of ALCL were immunostained using anti-p80 antibody, and 30 of them were shown to express p80. Clinicopathologic comparison between p80-positive and -negative ALCLs showed that p80-positive cases occurred in a far younger patient age group (16.2 +/- 12.9 years; p80-negative cases, 51.0 +/- 22.3 years; P < .0001) and the patients showed a far better 5-year survival rate (79.8%; p80-negative group, 32.9%; P < .01). These data showed that p80-positive ALCL is a distinct entity both clinically and pathogenetically and should be differentiated from p80-negative ALCL.

Adolescent↗
PubMed1995

Incision activity of human apurinic endonuclease (Ape) at abasic site analogs in DNA.

The major apurinic/apyrimidinic (AP) endonuclease of human cells, the Ape protein, incises DNA adjacent to abasic sites to initiate DNA repair and counteract the cytotoxic and mutagenic effects of AP sites. Here we address the determinants of Ape AP endonuclease activity using duplex DNA substrates that contain synthetic analogs of AP sites: tetrahydrofuranyl (F), propanediol (P), ethanediol (E), or 2-(aminobutyl)-1,3-propanediol (Q). The last of these, a branched abasic structure, was a poor substrate for which Ape had kcat > 1000-fold lower than for F. In contrast, the specificity constant (kcat/Km) for E or P of Ape purified from HeLa cells was only 5-8-fold lower than for F. Positioning a phosphorothioate ester immediately 5' to F inhibited Ape incision activity 20-fold (Rp isomer) or > 10,000-fold (Sp isomer). Although Ape did not have detectable endonuclease activity toward single-stranded substrates or unmodified double-stranded DNA, the enzyme displayed a low level of 3'-exonuclease activity for duplex DNA (< 0.03% of its AP endonuclease activity), which was influenced by the reaction conditions. The base positioned opposite F did not dramatically affect the cleavage efficiency of Ape, but an F:F arrangement was cleaved at approximately one-third of the efficiency of F:C. A 3'-mismatch diminished P and E cleavage only slightly and F not at all. A 5'-mismatch reduced the Ape cleavage rate 4-10-fold for F and approximately 100-fold for P and E. A series of substrates with F at different positions along the oligonucleotide showed that Ape requires > or = 4 base pairs 5' to the abasic site and > or = 3 base pairs on the 3'-side. The implications of these results for substrate recognition by Ape are discussed.

Base Sequence↗
PubMed1995

Human and viral interleukin-10 in Hodgkin's disease, and its influence on CD4+ and CD8+ T lymphocytes.

The Epstein-Barr virus (EBV) is closely related to Hodgkin's disease (HD), while the BCRF-I (viral [v] IL-10) gene of the EBV is highly homologous to the human interleukin-10 (h IL-10) gene. To investigate the relationship of IL-10 and HD, we performed both immunostaining and in situ hybridization (ISH) in 30 cases of HD. The presence of EBV in Hodgkin (H) and Reed-Sternberg (RS) cells was seen in 16 of the 30 cases, by ISH of the EBV EBER-I region and/or immunostaining of latent membrane protein (LMP-I). Of the 16 EBV-positive cases, 12 also showed IL-10 antigen (Ag) in H and RS cells by immunostaining, 5 of the 16 demonstrated hIL-10 RNA by ISH and 14 of the 16 showed vIL-10 RNA. But only 2 of the 14 EBV-negative cases showed IL-10 Ag, and one of them showed hIL-10 RNA, while none demonstrated vIL-10 RNA. The T cells in the HD-involved tissues were found to be mainly CD4-positive T cells, and had no association with EBV infection. However, the lymphocytes surrounding H and RS cells were more frequently CD4 cells and rarely CD8 cells in the EBV-positive cases, in contrast with the EBV-negative cases. The above results indicate that an EBV infection influenced both cytokine synthesis and the response of T cells in HD.

CD4-Positive T-Lymphocytes↗
PubMed1995

Transient kinetics of intracomplex electron transfer in the human cytochrome b5 reductase-cytochrome b5 system: NAD+ modulates protein-protein binding and electron transfer.

Transient kinetics of reduction and interprotein electron transfer in the human cytochrome b5 reductase-cytochrome b5 (b5R-b5) system was studied by laser flash photolysis in the presence of 5-deazariboflavin and EDTA at pH 7.0. Flash-induced reduction of the FAD cofactor of b5R by deazariboflavin semiquinone (in the absence of b5) occurred in a rapid second-order reaction (k2 = 3.1 x 10(8) M-1 s-1) and resulted in a neutral (blue) FAD semiquinone. The heme of cytochrome b5 (in the absence of b5R) was also rapidly reduced in this system with k2 = 3.1 x 10(8) M-1 s-1. When the two proteins were mixed at low ionic strength, a strong complex was formed. Although the heme of complexed b5 could be directly reduced by deazariboflavin semiquinone, the second-order rate constant was nearly an order of magnitude smaller than that of free b5 (k2 = 3.4 x 10(7) M-1 s-1). In contrast, access to the FAD of b5R by the external reductant was decreased by considerably more than an order of magnitude (k2 < 1 x 10(7) M-1 s-1). When an excess of b5R was titrated with small increments of b5 and then subjected to laser flash photolysis in the presence of deazariboflavin/EDTA, interprotein electron transfer from the b5R FAD semiquinone to the heme of b5 could be observed. At low ionic strength (I = 16 mM), the reaction showed saturation behavior with respect to the b5 concentration, with a limiting first-order rate constant for interprotein electron transfer k1 = 375 s-1, and a dissociation constant for protein-protein transient complex formation of approximately 1 microM. The observed rate constants for interprotein electron transfer decreased 23-fold when the ionic strength was increased to 1 M, indicating a plus-minus electrostatic interaction between the two proteins. Saturation kinetics were also observed at I = 56, 96, and 120 mM, with limiting first-order rate constants of 195, 155, and 63 s-1, respectively. In the presence of NAD+, the transient protein-protein complex was stabilized by approximately a factor of two, and limiting first-order rate constants of 360 s-1 were obtained at both I = 56 mM and I = 96 mM and 235 s-1 at I = 120 mM. Thus, NAD+ appears to stabilize as well as to optimize the protein-protein complex with respect to electron transfer. Another effect of NAD+ is to appreciably slow autoxidation and disproportionation of the FAD semiquinone.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytochrome Reductases↗
PubMed1995

A megakaryocyte analysis of the bone marrow in patients with myelodysplastic syndrome, myeloproliferative disorder and allied disorders.

A morphometric analysis was performed on aspirate clots of bone marrow to identify the presence of atypical megakaryocytes after immunohistological staining with a monoclonal antibody against Factor VIII. This study included cases of myelodysplastic syndrome (MDS), myeloproliferative disorder (MPD), aplastic anaemia (AA), idiopathic thrombocytopenic purpura (ITP), chronic myelogenous leukaemia (CML), and control cases free from any haematological disease. Quantitative and qualitative abnormalities of megakaryocytes were assessed using an image analyser and a personal computer to perform a morphometric analysis of the number (per mm2), arrangement (microns), nuclear size (microns2), cell size (microns2), nuclear size/cell size (N/C) ratio, and nuclear contour index (NCI). Micromononuclear megakaryocytes were detected in MDS, while in MPD, large over-mature magakaryocytes were observed to increase in number. In AA, the megakaryocytes decreased dramatically in number without showing any morphological abnormality. In CML, the megakaryocytes also increased without any remarkable morphological abnormality. In ITP, only the NCI increased. The above results show that MDS is characterized by the presence of atypical micromegakaryocytes, while MPD is characterized by atypical large over-mature megakaryocytes.

Antibodies, Monoclonal↗
PubMed1995

CD30-positive anaplastic large cell lymphoma in a human T-cell lymphotropic virus-I endemic area.

Clinicopathological and cytogenetic studies were performed on specimens from 43 patients with CD30-positive anaplastic large cell lymphoma (ALCL). All patients were born and lived in a human T-cell lymphotropic virus (HTLV)-I endemic area. Twenty-one patients (48.8%) had serum anti-HTLV-I antibody suggesting the presence of adult T-cell leukemia/lymphoma (ATL). Seventeen of them showed a clonal integration of complete HTLV-I proviral DNA by the Southern blot hybridization method in materials obtained by biopsy. Their ages ranged from 37 to 81 years (median, 67.0), and they frequently presented with lymphadenopathy (82.4%) and extranodal tumors with (76.5%) as well as with rare leukemic changes (5.9%). Immunohistologically the lymphoma cells in 15 ATL patients showed a T-cell phenotype. In only one patient (5.9%) was there an expression of epithelial membrane antigen (EMA) in most of the lymphoma cells. Cytogenetically aberration of chromosome band 5q35 was not found in seven patients with HTLV-I proviral DNA. The overall median length of survival was 11.9 months for the patients with HTLV-I proviral DNA, indicating a worse prognosis compared with that of the age-matched patients with negative anti-HTLV-I antibody (P < .01). The specimens of the patients with HTLV-I proviral DNA had unique clinicopathological and cytogenetic features. These findings suggested that T-cell ALCL with HTLV-I proviral DNA should be considered to represent the lymphoma type of ATL.

Adult↗
PubMed1995

Angiocentric immunoproliferative lesions of the skin show lobular panniculitis and are mainly disorders of large granular lymphocytes.

Eleven patients with angiocentric immunoproliferative lesion (AIL) of the skin were studied. Histologically, three patients were grouped into AIL grade II (AIL-II), whereas eight showed angiocentric lymphoma (AIL-III). All the patients' specimens exhibited lobular panniculitis. Infiltrating atypical lymphocytes in nine patients possessed electron-dense membrane bound granules in electron microscopy. Phenotypically, the lymphoid cells in the AIL-II patients were positive for CD3 epsilon; two of these showed a positive reaction to CD2, CD7, and CD8, but lacked natural killer-associated (NKa) antigens CD16, CD56, and CD57. In six AIL-III patients, lymphoma cells were positive for CD2 in all patients, CD56 in five, CD3 epsilon in four, CD7 in four, interleukin-2 beta receptor in four, a pore-forming protein in four, and CD30 in three patients. The remaining two AIL-III patients had B-cell lymphoma. By the Southern blot analysis, three patients with AIL-III showed a rearranged T-cell-receptor beta-gene or a deletion of its germline. The preceding results in nine of 11 patients suggest that abnormal or neoplastic large granular lymphocytes with the characteristics of T and NK cells have an important role in producing the angiocentric/angiodestructive features and lobular panniculitis. Clinically, all three patients with AIL-II and four with AIL-III showed liver dysfunction, cytopenia, and abnormal coagulopathy during the clinical course. Five patients with AIL-III died within 8 months. The histological grading of AIL, patients' age, and limited clinical stage of the disease seem to correlate with response to the treatment and prognosis.

Adolescent↗
PubMed1995

Management of intracranial hemorrhage associated with anticoagulant therapy.

BACKGROUND: Intracranial hemorrhage may be a particularly devastating complication of anticoagulant therapy. Very few accounts have reported data on the duration of anticoagulant discontinuation following intracranial hemorrhage or the intensity of anticoagulation during treatment for it, although we must adequately manage such a complication. METHODS: We analyzed the management of warfarin-related intracranial hemorrhages in 27 patients with cardiac diseases. We evaluated the degree of anticoagulation using the thrombotest. Anticoagulants were stopped as soon as the diagnosis of intracranial hemorrhage was established by computed tomographic scan. RESULTS: Mechanical valve prosthesis patients, who required intensive long-term anticoagulant therapy, constituted the majority of our series (74.1%). Intraoperative hemostasis was brought under control despite low thrombotest values (13%-68%) at the time of surgery except for the acute subdural hematoma (SDH) patients with cerebral contusion. Early resumption of anticoagulant therapy (within 3 days) did not cause intracranial rebleeding in any operative patient. All the chronic SDH patients and some of the subcortical hematoma patients had a good outcome. All three patients with acute SDH and contusion, however, had a fatal outcome because of intracranial rebleeding within a short period of time or ineffective intraoperative hemostasis. CONCLUSIONS: The patients with anticoagulant-related intracranial hemorrhage may undergo surgery with thrombotest values approximately between 20% and 60%, and anticoagulants can be resumed after an interval of 3 days. Aggressive surgery should particularly be performed in patients with anticoagulation-related chronic SDH or subcortical hemorrhage, as in the cases of anticoagulant-unrelated intracranial hemorrhage.

Adolescent↗
PubMed1995

Effect of a novel anti-rheumatic drug, TA-383, on type II collagen-induced arthritis.

The effects of Ta-383 (0.016, 0.08, 0.4, 2 and 10 mg/kg) and anti-rheumatic drugs (lobenzarit 10 and 50 mg/kg, dexamethasone 0.25 mg/kg) were evaluated on type II collagen-induced arthritis in DBA/1J mice. The arthritis score was markedly suppressed in the groups treated with dexamethasone and TA-383. Serum anti-type II collagen IgG was significantly suppressed in the groups treated with dexamethasone and 0.4 mg/kg TA-383. Histopathological evaluation of the knee joints revealed suppression of the inflammatory changes in the groups treated with dexamethasone and TA-383. These findings suggest that the histopathological examination of the joints of the animal model is useful for the evaluation of anti-rheumatic drugs, and that TA-383 has suppressive effects on type II collagen-induced arthritis, an animal model for human rheumatoid arthritis.

Animals↗
PubMed1995

Demonstration of Epstein-Barr virus genomes, using polymerase chain reaction in situ hybridization in paraffin-embedded lymphoid tissues.

We used the polymerase chain reaction (PCR) in situ hybridization (ISH) (PCR-ISH) on sections of malignant lymphoma and nonspecific lymphadenitis to detect small amounts of Epstein-Barr virus (EBV), a DNA virus of the herpes virus family. We first surveyed the EBV DNA by Southern blot analysis and PCR, and then compared results of the two PCR/ISH methodologies with the results of simplified/sensitive ISH for the positive cases. The target of the simplified in situ (DNA-ISH) was a few copies of EBV DNA per cell, and the target of the sensitive in situ (RNA-ISH) was as many as 10(7) copies of EBV RNA per cell. When EBV DNA was detected by Southern blot, DNA-ISH, RNA-ISH and PCR-ISH all revealed EBV genomes. When PCR revealed only amplified EBV DNA, DNA-ISH showed no EBV genomes, but PCR-ISH and RNA-ISH showed EBV genomes in a few cells. When PCR showed no detectable amplified EBV DNA, all of DNA-ISH, RNA-ISH and PCR-ISH showed no genomes. These findings indicate that PCR-ISH consistently detected a few copies of the EBV virions. The PCR-ISH was as sensitive as RNA-ISH. The RNA-ISH could not detect virus if RNA was not expressed, but the PCR-ISH could detect virus without such expression. The ability to detect a single copy of a specific gene in situ has many advantages and multiple applications in molecular biology, pathology, and cell biology.

Base Sequence↗
PubMed1995

Limited TCR V beta usage of infiltrating T cells in synovial tissues from patients with HTLV-I associated arthropathy.

Human T cell lymphotropic virus type-I (HTLV-I) is the etiologic agent of adult T cell leukemia/lymphoma and recently has also been suggested to be involved in chronic arthritis. The synovia of patients with rheumatoid arthritis (RA) contains activated T lymphocytes, with a restricted expression of T cell receptor (TCR) variable (V) beta gene segments. To characterize the T-cell populations of RA among HTLV-I carriers and noncarriers, we performed the immunohistochemical staining of CD4 and CDB, as well as a reverse transcription polymerase chain reaction (RT-PCR) to estimate the proportion of TCR beta RNA containing any particular V elements on the synovial specimens. In all but one HTLV-I carrier, the proviral DNA and/or RNA expression of HTLV-I was detected in the synovium. The CD4-positive cells proliferated markedly in the HTLV-I carriers compared with the noncarriers. In contrast to mononuclear cells in the peripheral blood, synovial T cells expressed only a few V beta transcripts, and no definite difference was observed between the carriers and the noncarriers. These results suggest that a common major antigen associated with the pathogenesis of RA may thus selectively interact with the V beta component of the TCR. Using RT-PCR, we studied the expression of the recombination-activating gene-1 (RAG-1), which was used in the V(D)J recombination of immunoglobulin and TCR genes. In all cases, RAG-1 was transcripted. The results supported the possibility that the extrathymic development of the selected TCR V beta T cells occurred in the synovia.

Adult↗
PubMed1995

CD30 (Ki-1) expression in adult T-cell leukaemia/lymphoma is associated with distinctive immunohistological and clinical characteristics.

Twenty-one patients with CD30 (Ki-1) positive lymphoma were studied from a group of 91 patients with adult T-cell leukaemia/lymphoma. The patients were grouped into three types: diffuse CD30 positive anaplastic large cell lymphoma in 11 patients (group 1); pleomorphic type lymphoma with diffuse CD30 expression in five patients (group 2); and pleomorphic type lymphoma with positive CD30 expression in large cells but negative in medium-sized and small cells in five patients (group 3). The patients with diffuse CD30 positive lymphomas (groups 1, 2) frequently presented with extranodal tumours (68.8%) and lymph node enlargement greater than 2 cm in diameter (50%), and rarely with leukaemic changes, bone marrow involvement and hypercalcaemia (one case of each). Patients in group 3 rarely had extranodal tumours, but had frequent leukaemic changes. Expression of intercellular adhesion molecule (ICAM-1; CD54) by the lymphoma cells in 13 patients (81.3%) with diffuse CD30 positive lymphomas, was significantly higher than that in 33 patients (9.1%) with CD30 negative adult T-cell leukaemia/ lymphomas. No positive reaction for epithelial membrane antigen (EMA) was found in the lymphoma cells of CD30 positive cases. The overall survival in patients with diffuse CD30 positive lymphomas was better than that of CD30 negative adult T-cell leukaemia/lymphoma patients, but showed no significant difference. These findings suggest that diffuse CD30 positive adult T-cell leukaemia/lymphoma has unusual clinical and immunohistological findings. It is also speculated that local tumour formation and leukaemic changes in such diffuse CD30 positive cases are influenced by CD54 (ICAM-1) expression by the lymphoma cells.

Adult↗
PubMed1995

High incidence of Haemophilus influenzae in nasopharyngeal secretions and middle ear effusions as detected by PCR.

PCR was used to detect Haemophilus influenzae in samples of nasopharyngeal secretion and middle ear effusion (MEE). Nasopharyngeal secretions were collected from 102 patients with otitis media with effusion and from 111 healthy subjects. Eighty samples of MEE were collected from patients with otitis media with effusion. A pair of primers was designed to amplify a DNA segment of the gene encoding P6 outer membrane protein of H. influenzae. The amplified PCR product was detected with an internal probe that hybridized specifically to the P6 DNA of H. influenzae. Samples of MEE and nasopharyngeal secretion were also examined by a conventional culture method. The incidence of P6 gene DNA in nasopharyngeal secretions detected by PCR was about two times higher than that of H. influenzae detected by the conventional culture. Culture-positive samples were all positive in the PCR test. In MEEs, the rate of detection of the P6 gene DNA target was about five times higher than that of H. influenzae detected by the culture method. All patients who had P6 gene DNA in MEEs were found to have the DNA in nasopharyngeal secretions. These findings suggest that the presence of H. influenzae in MEEs and in nasopharyngeal secretions is more common than previously reported.

Bacteriological Techniques↗
PubMed1995

Synthesis of 2-(2-hydroxyalkylidene)cyclopentanones and their bio-antimutagenic activity.

2-(2-Hydroxyalkylidene)cyclopentanones (1) and 5-(2-hydroxyoctylidene)-2-cyclopentenone (2) were synthesized by the aldol reaction of cyclopentanone-enolate (3)/cyclopentenone-enolate (19) with 2-bromoalkanals (4)/2-bromooctanal (4c) and subsequent treatment of the products with sodium acetate. The stereochemistry of the condensation, substitution and elimination was elucidated. The bio-antimutagenic activity of 1 increased as the 2-hydroxyalkylidene group increased in length up to = CHCH(OH)C8H17.

Antimutagenic Agents↗
PubMed1995

Initial arthritic lesions induced by immunization with type II collagen in Lewis rats.

Lewis rats were immunized with an intradermal injection of type II collagen to study the time course of arthritic lesions. Serum type II collagen antibody was detected 9 days after immunization. Increased paw volume in the hind limbs was noted on day 11. Histopathologically, proliferation of synovial lining cells was observed on day 11 and typical lesions similar to those of human rheumatoid arthritis were noted on day 18.

Animals↗