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K Oguma

Publications and source records attributed to K Oguma.

At least 127 records · Page 7Linked to original sources
PubMed1989

Binding of Clostridium botulinum type C neurotoxin to different neuroblastoma cell lines.

Binding of type C neurotoxin (C1 toxin) from Clostridium botulinum (strain Stockholm) to neuroblastoma cell lines was studied by using biotinylated anti-toxin antibody and avidin-biotinylated peroxidase complex. The neurotoxin bound with high efficiency to mouse neuroblastoma (NS-20Y and NIE-115) cells and to hybridomas of rat glioblastoma and mouse neuroblastoma (NG108-C15) cells. The toxin bound little to human neuroblastoma, rat astrocytoma, and nonneural cell lines. Binding of the neurotoxin to NG108-C15 cells was inhibited by gangliosides (GT1b and GM1) and by monoclonal antibodies (CA-12 and C-9), although inhibition was not complete. Sequential preincubation of C1 toxin with GT1b and CA-12 caused complete inhibition. A Scatchard plot of binding of 125I-labeled C1 toxin to NG108-C15 cells showed a hyperbolic curve. Monoclonal antibody CA-12 but not C-9 neutralized the lethal activity of the toxin toward mice. Only C-9 clearly inhibited toxin binding to GT1b. These results suggest that NG108-C15 cells have at least two kinds of receptors for C1 toxin. From the results of binding tests with neuraminidase-, pronase-, and trypsin-treated NG108-C15 cells, the chemical nature of the high-affinity site was presumed to be a glycoprotein containing sialic acid. GT1b may have an important role in low-affinity sites.

Animals↗
PubMed1989

Molecular diversity of neurotoxins from Clostridium botulinum type D strains.

The molecular properties of Clostridium botulinum type D South African (D-SA) were compared with those of neurotoxins from type D strain 1873 (D-1873) and type C strains Stockholm and 6813. D-SA toxin, purified 610-fold from the culture supernatant in an overall yield of 30%, consisted of an intact peptide chain with a molecular weight of 140,000. Limited proteolysis of the toxin by trypsin formed a dichain structure consisting of a light chain (Mr, 50,000) and a heavy chain (Mr, 90,000) linked by a disulfide bond(s) and enhanced the lethal activity about fourfold. Antibodies against the D-SA toxin light chain reacted with D-1873 toxin but not with C1 toxins. On the other hand, antibodies against the heavy chain of D-SA toxin cross-reacted with type C strain Stockholm, D-1873, and type C strain 6813 toxins in that order. Amino-terminal sequences of heavy and light chains of D-SA and D-1873 toxins were similar but not identical. These results indicate that within the type D strains, neurotoxins differ in molecular structure and antigenicity.

Amino Acid Sequence↗
PubMed1989

Biological effects of lipopolysaccharide from Achromobacter stenohalis on lymphocytes and macrophages.

The immunopotentiating activities of lipopolysaccharide from Achromobacter stenohalis (A-LPS) were examined. A-LPS was structurally atypical and gave no endotoxin shock in A-LPS-inoculated mice. Analysis in vitro showed that A-LPS was a potent activator of both macrophages and B-lymphocytes. After macrophage stimulation with A-LPS, interleukin-1 (IL-1) secretion, interferon (IFN) production and chemiluminescence (CL) response were induced. A-LPS was a potent mitogen for spleen lymphocytes. However, induction of interleukin-2 (IL-2) secretion in T lymphocytes was not observed. These activities of A-LPS were similar to or higher than that of enterobacterial LPS.

Alcaligenes↗
PubMed1989

The effect of bispecific monoclonal antibody recognizing both hepatoma-specific membrane glycoprotein and anthracycline drugs on the metastatic growth of hepatoma AH66.

A monoclonal mouse antibody (MoHG) was produced using in vitro cultured AH66R tumor cells treated with cholesteryl hemisuccinate as an immunogen. The antibody identified a 90 kd membrane glycoprotein (HG-90) which is expressed on in vitro cultured hepatoma cell lines AH66 and AH66R. A monoclonal antibody was prepared to the anthracycline drug daunomycin, and it also reacted with adriamycin. A fusion was made of the hybridoma HG-90 with the hybridoma which recognized daunomycin/adriamycin. This bispecific hybridoma A8C recognized both determinants. We studied the therapeutic effect of the A8C bispecific antibody with adriamycin treatment and compared it to the effect of the bispecific antibody to which adriamycin had been conjugated via an albumin (Alb) bridge. The therapy model used was the tumor AH66R in Donryu rats. Tumor bearing rats had their subcutaneous tumors resected on day 10, a time when distant metastases were present. After the surgical resection of the tumor the rats were injected intravenously for two cycles with the bispecific antibodies, followed by the administration of adriamycin (ADR) or MoHG.Alb.ADR conjugates. A slight therapeutic effect occurred with either MoHG or ADR alone but treatment with the bispecific antibody followed by the administration of ADR or with the MoHG.Alb.ADR conjugates significantly prolonged survival, with 60% of the treated animals being "tumor free" when sacrificed on day 80. Lower serum concentrations of alphafetoprotein were observed with the bispecific antibody and drug treatment. This suggests that the bispecific antibody/drug treatment is potentially more beneficial in the suppression of distant metastases than the MoHG.Alb.ADR conjugate. This may be due to an increase in the local drug concentration of unmodified adriamycin.

Animals↗
PubMed1988

Decrease of oligo-2',5'-adenylate synthetase activity in BALB3T3 cell persistently infected with Moloney murine leukemia virus.

The induction of oligo-2',5'-adenylate synthetase (2-5AS) activity by interferon (IFN) was decreased in BALB3T3 cells persistently infected with Moloney murine leukemia virus (Mo-MLV) as compared with uninfected cells. Furthermore, the correlation between increased susceptibility to vesicular stomatitis virus (VSV) infection and reduced 2-5AS activity was recognized in the Mo-MLV persistently infected cells. The decrease of enzyme activity was confirmed by a solid phase reaction and an analysis of reaction products by Fast Polynucleotide Liquid Chromatography (FPLC) in addition to a liquid phase reaction. In a solid-phase reaction, the enzyme protein binds to polyinosinate-cytidylate (Poly I:C) agarose beads and other cellular proteins can be washed out from the reaction mixtures. Therefore, these results indicate that the decrease of IFN-induced enzyme activity is due to the suppression of transcription and/or translation of 2-5AS mRNA. A decreased amount of 2-5AS mRNA in persistently infected cells was observed by Northern blot and dot-blot hybridization. On the other hand, cell lysate of Mo-MLV infected cells inhibited the 2-5AS activity in liquid phase reaction. The inhibition may also be partly due to the degradation of oligo-2',5'-adenylate (2-5A) formed by 2-5AS.

2',5'-Oligoadenylate Synthetase↗
PubMed1988

Histological changes and some in vitro biological activities induced by lipopolysaccharide from Bacteroides gingivalis.

The biological activities of lipopolysaccharide from Bacteroides gingivalis 381 (B-LPS) were examined in vivo and in vitro. Intra-oral mucosal injection of B-LPS induced an acute inflammation at the injection site. Intravenous injection of B-LPS induced necrotic lesions with many thrombi in the liver and lymphocytic reduction in the spleen. By immunohistochemical examination, B-LPS was detected in macrophages in the liver, spleen and lymph nodes. In vitro analysis showed that B-LPS was a potent activator of both neutrophils and macrophages in luminol-dependent response and IL-1 secretion from macrophages and was mitogenic to the spleen cells not only from BALB/c mice but also from LPS-non-responder C3H/HeJ mice. Interferon production from human peripheral mononuclear leucocytes was induced, in vitro, by stimulation with B-LPS but not with the other enterobacterial LPS. These findings clarified the various biological activities of B-LPS affecting various cells and tissues, especially neutrophils, macrophages and lymphocytes. The potent inflammability of B-LPS shown in the present study indicates that it is one of the effective agents to induce periodontitis.

Animals↗
PubMed1988

Oligo-2',5'-adenylate synthetase activity in K562 cell lines persistently infected with measles or mumps virus.

Fluctuation of oligo-2',5'-adenylate synthetase (2-5AS) activity was examined in K562 cells infected with vaccine strains of measles virus (strains AIK-C and CAM-70) and mumps virus (strains Torii and Miyahara). Persistent infection was easily established in the mumps virus-infected cells without significant cytolysis or cell killing. In contrast, most of the cells infected with measles virus were killed by extensive cytolysis within 3 to 4 days. The small number of cells that did survive became persistently infected. That these persistently infected cells carried a virus antigen was confirmed by fluorescein isothiocyanate-labelled anti-measles virus rabbit antiserum and anti-mumps virus rabbit antiserum. The cells produced infectious progeny virus as well as interferon (IFN). Little induction of 2-5AS activity by IFN was demonstrated during the early stages of infection by these viruses. Similar results were observed in some of the persistently infected cells but not, however, K-CMP cells (K562 cells persistently infected with CAM-70) or K-MMP cells (K562 cells persistently infected with Miyahara). Failure to induce 2-5AS activity was unchanged in cells cultured for more than 6 months. The decrease of 2-5AS activity observed in K-MTP cells (K562 cells persistently infected with Torii) was the result of suppression of transcription of 2-5AS mRNA. On the other hand, a normal level of mRNA was found in K-AKP cells (K562 cells persistently infected with AIK-C). Therefore, it is suggested that the decrease of 2-5AS activity in K-AKP cells may be due to a failure to translate 2-5AS mRNA.

2',5'-Oligoadenylate Synthetase↗
PubMed1988

Characterization of bacteriophage nucleic acids obtained from Clostridium botulinum types C and D.

Nontoxigenic strains of Clostridium botulinum types C and D are converted to toxigenic strains by infection with specific Tox+ bacteriophages. The nucleic acids were extracted from five converting phages, c-st, c-468, c-203, c-d6f, and d-1873, and one nonconverting phage, c-n71, and treated with nucleases. The nucleic acids isolated were not digested by RNase A, but were digested by DNase I and exonuclease III, indicating that they were double-stranded DNA. On the basis of the restriction endonuclease digestion patterns on 0.8% agarose gel electrophoresis, the length of c-st, c-n71, c-468, and c-d6f phage DNAs was estimated to be about 110 kilobase pairs and that of c-203 and d-1873 was about 150 kilobase pairs. The digestion patterns of c-st, c-468, and c-n71 phage DNAs by PstI and HindIII were very similar. High homology was observed in the dot hybridization test. For other phages and nucleases, a good similarity was not observed. Only a little similarity was observed between c-203 and c-d6f phages. The existence of the structural genes for the toxin in both c-st and c-n71 phages was confirmed by the hybridization test with these phage DNAs and the oligonucleotide probe which represented the DNA sequence predicted for the N-terminal amino acids (2 to 17) of C. botulinum type C toxin. The loss of the converting ability of c-n71 phage may be caused not by the deletion of the tox+ gene but rather by the base mutation in c-st phage DNA.

Amino Acid Sequence↗
PubMed1988

Establishment of a monoclonal antibody recognizing an antigenic site common to Clostridium botulinum type B, C1, D, and E toxins and tetanus toxin.

The partial amino acid sequence of the light-chain (Lc) component of Clostridium botulinum type C1 toxin was determined. The sequence was quite similar to those of the other types of botulinum and tetanus toxins. Nine monoclonal antibodies against botulinum type E toxin were established by immunizing BALB/c mice with type E toxoid or its Lc component. Six antibodies reacted with the heavy-chain component and three reacted with the Lc component of the toxin. One of the latter three antibodies reacted with botulinum type B, C1, and D toxins and tetanus toxin, as well as botulinum type E toxin. This antibody recognized the Lc components of these toxins, indicating that there exists one common antigenic determinant on the Lc regions of these toxins.

Amino Acid Sequence↗
PubMed1987

Binding and cytotoxic effects of Clostridium botulinum type A, C1 and E toxins in primary neuron cultures from foetal mouse brains.

Binding of purified Clostridium botulinum type A, C1 and E toxins to cultured cells was studied by an immunocytochemical method. Type A and C1 toxins bound strongly to neuron cultures prepared from brains of foetal mice, but binding of type E toxin was weak. None of the toxin types bound to the feeder layer, composed of non-neuronal cells. The heavy-chain component of the type C1 toxin bound to neurons, but the light chain component did not. Type C1 toxin also bound only to cell lines of neuronal origin. When type C1 toxin [final concentration 4 x 10(2) LD50 (10 ng) per well] was added to primary neuron cultures in 96-well plates, degeneration of neuronal processes and rounding of neuronal somas were observed, but type A and E toxins did not produce such changes. The binding and cytotoxic activities of type C1 toxin were blocked by heat treatment (80 degrees C for 30 min) or by preincubation of the toxin with polyclonal anti-C1 IgG and some of the monoclonal antibodies which neutralized the toxin activity in mice. In the neuronal processes treated with C1 toxin, many degenerated mitochondria, membranous dense bodies and vesicles were observed by electron microscopy; these ultrastructural changes were similar to those of Wallerian degeneration in vivo.

Animals↗
PubMed1987

Increased activity of oligo-2',5'-adenylate synthetase in Down's syndrome and epilepsy.

The level of oligo-2',5'-adenylate synthetase activity is a good marker for the response of cells to interferon. This enzyme can polymerize ATP to form oligonucleotides in the presence of double-stranded RNA, i.e. polyinosinate-cytidylate in vitro. The activity of this enzyme in peripheral blood mononuclear leucocytes was significantly increased in Down's syndrome (P less than 0.01) and epilepsy (P less than 0.01) compared with that in healthy controls, but the increase of activity was not significant in multi-infarct dementia (MID) (P greater than 0.05). Although the patients with Down's syndrome showed higher levels of this enzyme activity than the controls, interferon activity was never detected in the circulation. In addition, the serum of patients with Down's syndrome lacked the capacity to induce this enzyme in NC-37 and FL cells, and furthermore it was shown that the inhibitor of interferon activity was not found in the serum of patients. This discrepancy in Down's syndrome may be the result of the hypersensitivity of cells to interferon. On the contrary, interferon activity (32 IU/ml) was detectable in the circulation of one patient with epilepsy, and the serum of this patient had the capacity to induce this enzyme in NC-37 and FL cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1987

[A case of pericarditis carcinomatosa showing good response following local transfer of lymphokine-activated killer (LAK) cells].

A good therapeutic response following local transfer of lymphokine-activated killer (LAK) cells was obtained in a patient with cardiac tamponade due to breast carcinoma. A 41-year-old female was admitted with complaints of dyspnea and tachycardia. She had undergone left mastectomy at the age of 37 years and had received continuous oral administration of tamoxifen. Chest roentgenogram revealed cardiomegaly (CTR = 65%) and cardiac echogram showed marked retention of pericardial effusion. The cytology of the effusion was class V (adenocarcinoma). Cardiac tamponade proved refractory to combination chemotherapy using adriamycin, cyclophosphamide and 5-fluorouracil, and the effect of paracentesis was only temporary. Autologous peripheral blood lymphocytes were obtained through the cubital vein and cultured in vitro with 2 units/ml of human recombinant IL-2, (TGP-3, Takeda Pharm. Co.). After 4 days of cultivation, LAK cells were transferred intrapericardially 3 times. The cumulative infusion dose was 1.2 X 10(8) cells and the amount of combined IL-2 administration was 100 units/each transfer. Twenty-four days after initial infusion of LAK cells, the effusion disappeared. After then, recurrence has not been observed for 287 days. This case is the first trial of LAK therapy against pericarditis carcinomatosa and seems to be a useful way of treating this uncontrollable state without any serious side effects.

Adenocarcinoma↗
PubMed1987

[The therapeutic effect of norfloxacin on chronic prostatitis].

The clinical efficacy of norfloxacin (NFLX) was evaluated in 74 patients having chronic prostatitis with the subjective symptoms suggesting the inflammations of prostate and more than five white bloodcells (WBCs)/hpf in their prostatic secretions (EPS). Of these, gram negative rods with greater than or equal to 10(3)CFU/ml (GNR group) were isolated from the EPS in 10 patients (13.6%) and gram positive cocci with greater than or equal to 10(3) CFU/ml (GPC group) were obtained in 46 patients (62.2%). E. coli (70.0%) was the most frequent strain isolated among GNR group and S. epidermidis (40.4%), S. aureus (19.1%), E. faecalis (17.0%) and S. haemolyticus (14.9%) were frequently isolated among the GPC group. The overall clinical efficacy of NFLX was determined at the second and fourth week by the three factors, (1) the effect on bacteria, (2) WBCs in the EPS and (3) the subjective symptoms in the patients with bacteria of greater than or equal to 10(3) CFU/ml being isolated. The overall clinical effectiveness rate was 71.4% and 100%, respectively, in the GNR group. In the GPC group, its rate was 79.3% and 88.0%, respectively. The patients with no bacteria or less than 10(3) CFU/ml isolated from the EPS had an overall clinical effectiveness rate of 89.8% at the second week and 90.0% at the fourth, when it was evaluated by the effect on WBCs and subjective symptoms. In the effect of NFLX on bacteria in the EPS, it eliminated them in 75.0% and 83.9% at the second and fourth week, respectively, of all patients with GNR or GPC of greater than or equal to 10(3) CFU/ml isolated from the EPS. The minimum inhibitory concentrations (MIC) of NFLX against E. coli isolated from the EPS was distributed from 0.025 microgram/ml to 3.13 micrograms/ml with most below 0.1 microgram/ml. Those against all other GNR were below 0.78 microgram/ml. NFLX showed good antimicrobial activities against GPC with most of MIC being distributed from 0.78 microgram/ml to 1.56 micrograms/ml. NFLX produced the highest eradication rate in bacteriological response not only against GNR such as 100% at the first, the second and fourth week but GPC as 89.2%, 93.8% and 96.0%, respectively. In the effect of NFLX on WBCs in EPS, 40-50% of patients got free from the inflammation of prostate by NFLX treatment. This became prominent in the GNR group as the treatment was continued although not in the GPC group. The subjective symptoms were improved by NFLX treatment in most of the patients.

Adult↗
PubMed1986

Induction of oligo-2',5'-adenylate synthetase in human lymphoid cells treated with 5-azacytosine and 5-iododeoxyuridine.

Oligo-2',5'-adenylate synthetase activity was investigated in several human lymphoblastoid cell lines of B cell origin treated with reagents having effects on gene expression, 5-azacytosine (5AZct), 5-azacytidine (5AZcd) and 5-iodo-2'-deoxyuridine (IUdR). Enzyme activity did not increase in cells treated with 5AZcd, but the other reagents induced significant levels of activity. Interferon (IFN) activity was not detected in culture fluids of cells treated with 5AZcd or 5AZct. On the other hand, treatment of cells with IUdR led to the production of 5 to 10 units/ml IFN by NC-37 and Raji cells, but not by other human B cell lines. Enzyme induction by IUdR occurred in IFN-producing cells, NC-37 and Raji, exposed to anti-IFN-alpha sera and also in IFN-non-producing human B cells. The effect of 5AZct on enzyme induction was observed only after cultivation of cells for more than 1 month. This compound could not induce enzyme activity in Epstein-Barr virus (EBV)-negative cells, BJAB, but only in the EBV-positive cell lines NC-37 and Raji. In contrast, treatment of cells with IUdR for only 3 days induced the enzyme in all human lymphoblastoid cell lines of B cell origin except P3HR-1, but not in other human cell lines, FL, HeLa and K562. Oligo-2',5'-adenylate synthetase activity in P3HR-1 cells, which produce EBV particles, was hardly affected by IUdR or IFN treatment.

2',5'-Oligoadenylate Synthetase↗