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Biomedical subjects

H Hojo

Publications and source records attributed to H Hojo.

At least 73 records · Page 4Linked to original sources
PubMed1994

Subcellular localization and characterization of interleukin-1 alpha produced by rat bladder cancer cells.

A rat bladder cancer cell line BC31ad, previously reported to constitutively release tumor necrosis factor alpha (TNF alpha), was found to produce an interleukin (IL)-1-like factor inducing proliferation of murine thymocytes in a standard costimulation assay (LAF activity). IL-1-like factor was partially purified by DEAE-Sephacel, Sephacryl S-200 and MonoQ-FPLC chromatographies from the serum-free conditioned medium of a BC31 adderived clone, C19, to the specific activity of 3.2 x 10(6) U/mg and characterized as a protein of molecular weight 17 kDa with isoelectric point 5.2. LAF activity of IL-1-like factor was specifically neutralized with anti-rat IL-1 alpha but not with anti-rat IL-1 beta. These findings show that the IL-1-like factor is rat IL-1 alpha, although the precise molecular relationship with monocyte IL-1 alpha is unclear. Furthermore, IL-1 alpha was shown to be primarily located in the cytosol and plasma membrane without spontaneous release. A kinetics study indicated that it was leaked into the medium late in culture resulting from cell destruction, in contrast to TNF alpha which was released as the cell number was increased. We discussed the possible role of IL-1 alpha as an autocrine or paracrine growth regulator.

Animals↗
PubMed1994

Differential induction of metallothionein synthesis by interleukin-6 and tumor necrosis factor-alpha in rat tissues.

Metallothionein (MT) synthesis induced by the inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF), was studied in vivo. Administration of recombinant human IL-6 or TNF to rats caused the acute phase responses including rapid decreases in plasma zinc (Zn), and increases in plasma copper (Cu) and ceruloplasmin. Hepatic concentration of MT-I, one of MT isoforms, began to increase within 3 h after the injection of IL-6 or TNF. In IL-6-treated rats, MT-I concentration in liver reached a maximum level at 12 h and decreased with a transient rebound, whereas, in TNF-treated rats, a high level of MT-I lasted for about 48 h. MT-II, the other MT isoform, was induced more than MT-I in liver by both cytokines. MT-I was also induced in lung and heart by TNF, but little by IL-6. The data suggest that IL-6 may be responsible for MT synthesis in liver, whereas TNF may be responsible not only in liver but also in lung and heart. Furthermore plasma concentration of MT did not always reflect the enhanced concentration of MT by TNF and IL-6 in liver, suggesting involvement of many factors influencing plasma MT levels. The interrelation between IL-6 and TNF for MT synthesis has also been discussed.

Animals↗
PubMed1994

Suppression of chemically and immunologically induced hepatic injuries by gentiopicroside in mice.

Gentiopicroside (GPS), a main bitter secoiridoid constituent of roots of Gentiana macrophylla Pall., was tested for therapeutic effects on the two hepatic injury models, the CCl4-induced and lipopolysaccharide (LPS)/bacillus Calmette-Guerin (BCG)-induced hepatitides. An increase in serum level of hepatic aminotransferases (GOT: EC 2.6.1.1. and GPT: EC 2.6.1.2.) induced by a p.o. treatment of CCl4 was suppressed by pretreatment with GPS at 30-60 mg/kg/day for 5 consecutive days. An increase of these enzymes triggered by an i.v. treatment with LPS in mice primed with bacillus Calmette-Guerin (BCG) was also inhibited by GPS pretreatment at the same dose of GPS. In the BCG/LPS model, tumor necrosis factor (TNF), a major inflammatory mediator, was increased in serum with a peak at 90-120 min, followed by an increase of serum transaminase activities. GPS treatment significantly suppressed the increase of TNF in serum at the therapeutic doses, suggesting that GPS protected against hepatitis by inhibiting the production of TNF.

Alanine Transaminase↗
PubMed1994

13C-NMR relaxation study on mobility of the DNA-binding arm of HU.

The mobility of the DNA-binding arm of HU protein was studied by 13C-NMR spectroscopy. The correlation times tau c of Phe47C alpha in the body and Gly60C alpha in the arm of HU were determined for HU and HU-DNA complex. The value of tau c of Phe47C alpha is 2-4 times larger than that of Gly60C alpha irrespective of the presence or absence of DNA. These results show that Gly60C alpha undergoes more rapid motion than Phe47C alpha. The increase in correlation time on addition of DNA is greater for Gly60C alpha than for Phe47C alpha. This suggests that the addition of DNA influences more significantly the motion of Gly60C alpha than that of Phe47C alpha. These results are in accord with the X-ray result, in which the top part of the arm is not visible. Gly60C alpha in the arm is thus more mobile than Phe47C alpha in the body, and the mobility of Gly60C alpha is reduced by the DNA binding.

Bacterial Proteins↗
PubMed1994

Derivation and application of monoclonal antibodies recognizing several epitopes on bovine serum albumin.

Three (AB-3, AB-4 and AB-6) monoclonal antibodies (mAb) to bovine serum albumin (BSA) were derived and characterized for their physicochemical and immunological properties. AB-3 recognized an epitope distinct from epitopes recognized by AB-4 and AB-6 as determined by binding inhibition assay. AB-4 and AB-6 mAbs recognized similar but not identical epitopes on BSA. Based on the antigenic specificity, we applied these mAbs to quantitative analysis of BSA in medium and to depletion of BSA from culture medium containing fetal calf serum (FCS). For quantitative analysis, we employed a sandwich enzyme-linked immunosorbent assay (ELISA) using biotinylated AB-3, solid-phase of AB-6 and an avidin-biotin-peroxidase complex system. This assay was highly sensitive and quantitative in the range of BSA concentration at 10 to 1,500 ng/ml. To deplete BSA from medium, we prepared affinity-gel coupled to AB-6. Repeated treatment of FCS-containing medium with the affinity-gel efficiently depleted BSA from the medium. The depletion capacity was 0.74 to 1.0 moles of BSA/mole of coupled mAb.

Animals↗
PubMed1994

Establishment of a human thymic stromal cell line (R-3-4) and its adhesive capacity with T cells in vitro.

T cells are considered to be activated in the thymus, and it has been emphasized recently that the thymic stromal cells play an important role in the process of T-cell maturation. To clarify how the stromal cells interact with T cells a cloned stromal cell line from human thymus was established and its adhesive capacity with T cells was studied. A recombinant plasmid, pSV3gpt containing SV40 large T antigen was introduced to human thymic stroma by the calcium phosphate co-precipitation method, and the thymic stromal cell line R-3-4 was obtained. Immunohistochemical examination showed that R-3-4 possessed with HLA-class 1 antigen, laminin, fibronectin, and keratin. To determine if the R-3-4 interacts with T cells, the binding activity of R-3-4 with T cells examined by using rosette formation technique. The R-3-4 formed rosette only with the T cells, but both B cells and myeloid cells did not bind to the R-3-4. This rosette formation between R-3-4 and T cells was inhibited when T cells were pretreated with anti-CD2 antibodies, suggesting that some mechanism involving CD2 participates in this binding. Our novel established thymic stromal cell line might be useful for studying the interactions between thymic stroma and T cells in vitro.

Antibodies, Monoclonal↗
PubMed1993

Inhibitory effect of bisbenzylisoquinoline alkaloids on nitric oxide production in activated macrophages.

Bisbenzylisoquinoline (BBI) alkaloids are anti-inflammatory constituents of plants of the families Menispermaceae and Ranunculaceae, which have been used as folk remedies in Japan and China. Five BBI alkaloids (cepharanthine, chondocurine, cycleanine, isotetrandrine and tetrandrine) were tested for suppressive effect on in vitro nitric oxide (NO) production by lipopolysaccharide-stimulated peritoneal macrophages, which were induced with thioglycollate or bacillus Calmette-Guerin in mice. All these BBI alkaloids significantly suppressed NO production at 5 micrograms/mL. Cepharanthine, isotetrandrine and cycleanine were slightly more inhibitory than tetrandrine and chondocurine. The suppression persisted for at least 48 hr. As NO is one of the critical mediators in inflammation, these results may explain some aspects of the anti-inflammatory mechanisms of BBI compounds.

Alkaloids↗
PubMed1993

Suppression of lipopolysaccharide-induced fulminant hepatitis and tumor necrosis factor production by bisbenzylisoquinoline alkaloids in bacillus Calmette-Guerin-treated mice.

The bisbenzylisoquinoline (BBI) alkaloids chondocurine, cycleanine, tetrandrine and berbamine were tested for their capacity to suppress hepatic injury and production of tumor necrosis factor (TNF) induced by lipopolysaccharide (LPS) in mice primed with bacillus Calmette-Guerin (BCG). When administered for three consecutive days before LPS injection, chondocurine, cycleanine and tetrandrine (10 mg/kg/day) strongly suppressed serum alanine aminotransferase (EC 2.6.1.1.) and aspartate aminotransferase (EC 2.6.1.2.); however, berbamine gave only slight protection. Chondocurine, cycleanine and tetrandrine but not berbamine significantly reduced the level of TNF which peaked 2 hr after LPS injection. This study shows that BBI alkaloids prevent BCG/LPS-induced hepatitis at least in part by suppressing TNF production.

Alkaloids↗
PubMed1993

An immunohistological study of post-transfusion graft-versus-host disease (GVHD).

We reported clinicopathological, histopathological and immunohistological features of two suggestive cases with post transfusion graft-versus-host disease (GVHD) and examined. In addition, we have declared histopathologic characteristics of acute and chronic GVHD with literatural consideration. On the basis of a review of two cases, we came to the following conclusion; It is implied that early lymphoid proliferation may be useful to make a diagnosis of acute GVHD. Case 2 had pathological confirmation of acute GVHD in the liver and small intestine. In the liver, a damage of interlobular bile ducts and T lymphocytes infiltration close to ducts were the most specific feature of acute GVHD. From an immunohistological study in case 2, it was confirmed that abnormal expression of HLA-DR antigen and the appearance of activated T lymphocytes played an important role in the development of GVHD reaction in the liver.

Graft vs Host Disease↗
PubMed1993

[A pilot study of induction chemotherapy with cisplatin, mitomycin C and vindesine for stage III N2 non-small cell lung cancer].

PURPOSE: The postoperative survival of patients with preoperatively identified stage III N2 non-small cell cancer (NSCLC) is poor. A pilot study of induction chemotherapy consisting of cisplatin, mitomycin C and vindesine (CMV) was undertaken in an attempt to improve the curative potential of surgery in this group of patients. PATIENTS AND METHODS: Thirty-two patients with stage III N2a NSCLC received two cycles of CMV, (80 mg/m2 cisplatin i.v. on day 1, 8 mg/m2 mitomycin C i.v. on day 1, and 3 mg/m2 vindesine i.v. on day 1 and 8, every 4 weeks) preoperatively. The responding patients received a further two courses of CMV after surgery. RESULTS: The response rate was 63% (20 PR). All patients underwent operation including radical mediastinal node dissection. Twenty-six resections were curative and six were absolute non-curative. The toxicity was generally mild, but there were two hospital deaths, due to bronchopleural fistula and postoperative pneumonia. Sixteen patients have shown recurrent disease up to now. When the recurrence patterns were classified by clinical response, 11 responding patients were disease-free (9-84 months), but all non-responding patients had recurrent diseases. The median survival of curatively resected patients with pathological N2 was 39 months with a 5-year survival of 29%. CONCLUSIONS: This induction chemotherapy was well tolerated and revealed a high response rate. The current survival is obviously improved compared with the historical control, indicating that subsequent phase III clinical trials are urgently needed.

Adult↗
PubMed1993

[Detection of erythropoietic inhibitor factor in a case of acute non-lymphocytic leukemia after allogenic bone marrow transplantation].

A 36-year-old man was diagnosed as having acute non-lymphocytic leukemia (AML M5b) in 1985 and received allogenic bone marrow transplantation from an ABO-mismatched sibling in January 1987. Recovery of erythropoiesis in this patient was delayed, then the hemoglobin level improved in parallel with disappearance of anti-A antibody in the serum on day 260 post transplantation. However, as anemia occurred again despite no relapse of leukemia on day 350, we tried to determine the presence of erythropoietic inhibitory factor in this patients. Erythroid colony formation was decreased when bone marrow cells were co-cultured with peripheral mononuclear cells from the patient. Further, erythroid colony inhibitory activity was found in conditioned medium of PHA-stimulated T cells from the patient. Sephadex gel fractionation showed that the molecular weight of this inhibitory factor was approximately 11,000 and addition of a high concentration of EPO did not eliminate the inhibitory activity. These findings suggest that the novel inhibitor described in this manuscript, produced by T cells, was differed from previously reported inhibitors such as anti-EPO antibody, spermine and uremic toxins.

ABO Blood-Group System↗
PubMed1992

Assembly regulatory domain of glial fibrillary acidic protein. A single phosphorylation diminishes its assembly-accelerating property.

Phosphorylation of glial fibrillary acidic protein (GFAP) induces disassembly of the filaments. An amino-terminal fragment of bovine GFAP (G-Hf) was produced by lysylendopeptidase digestion. G-Hf formed ribbon-like filaments in the presence of GFAP even in low ionic strength, whereas the fragment itself did not form any structures. Only one (PK3) of the five V8 protease fragments of G-Hf accelerated GFAP assembly to the same degree as G-Hf did, whereas the other fragments did not. When PK3 was cleaved into two fragments, it lost the assembly-accelerating property. The sequence of PK3 was determined as RRRVTSATRRSYVSSSE, which corresponded to residues 3-19 of porcine GFAP. It was concluded that PK3 contains a sequence indispensable for GFAP assembly and that neither PK1 (RRRVTS) nor PK2 (ATRRSYVSSSE) included all of the sequence. A single phosphorylation of PK3 by cyclic AMP-dependent protein kinase diminished its assembly-accelerating property. The phosphorylation site was determined as Ser-12 of porcine GFAP. It was shown that single phosphorylation of the amino-terminal head domain, which contains an indispensable sequence for GFAP assembly, might be sufficient for GFAP disassembly.

Amino Acid Sequence↗
PubMed1992

Histogenesis of diffuse small cleaved cell lymphoma. An immunohistochemical and molecular genetic (bcl-2 gene) study with comparison to follicular small cleaved cell lymphoma and mantle zone lymphoma.

Immunohistochemical and molecular genetic (bcl-2 gene) studies were performed on specimens from 24 patients with follicular small cleaved cell lymphoma (FSCCL), 24 patients with diffuse small cleaved cell lymphoma (DSCCL) and 4 patients with mantle zone lymphoma (MZL) to determine the cellular origin of the disease and whether or not DSCCL represents the diffuse counterpart of FSCCL. Two patients with FSCCL, 22 patients with DSCCL, and all of the patients with MZL had a phenotype of mantle zone (MZ) B-lymphocytes (SIgD+, Leu-1+, Leu-8+, positive alkaline phosphatase [ALPase+], and negative common acute lymphoblastic leukemia antigen [CALLA-]), and all the tested patients (2 patients with FSCCL, 13 patients with DSCCL, and 4 patients with MZL) had germlines of bcl-2 gene. Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements. These results indicate that FSCCL are almost always derived from FCC, whereas some FSCCL, most DSCCL, and all MZL are derived from MZ B-lymphocytes, and these lymphomas should be included in the same category as MZ B-lymphocyte-derived lymphomas. Histologically diagnosed DSCCL often may represent a diffuse counterpart of MZ B-lymphocyte-derived lymphoma. MZ B-lymphocyte-derived lymphomas histologically show a follicular (nodular), a follicular MZ, or a diffuse growth pattern and clinically show a high incidence of peripheral blood (PB) involvement or bone marrow (BM) involvement.

Adult↗
PubMed1992

Solution structure of a DNA-binding unit of Myb: a helix-turn-helix-related motif with conserved tryptophans forming a hydrophobic core.

The DNA-binding domain of the c-myb protooncogene product consists of three imperfect tandem repeats of 51 or 52 amino acids, each of which contains three conserved tryptophans, spaced 18 or 19 amino acids apart. The structure of the third repeat, which is essential for sequence-specific DNA binding, has been determined by NMR with distance geometry calculation. It includes three well-defined helices (residues 149-162, 166-172, and 178-187) maintained by a hydrophobic core that includes the three conserved tryptophans, together with two histidines. Helices 2 and 3 form a structure related to but distinct from a canonical helix-turn-helix motif. In particular, the turn between these helices is one amino acid longer than the corresponding turn in bacterial repressors and homeodomains and contains a proline residue. In addition, the architecture of the three helices is different from those of homeodomains and DNA-binding domains of bacterial repressors. Based on the present structure, the binding mode of Myb repeat 3 with a specific DNA is also discussed.

Amino Acid Sequence↗
PubMed1992

Detecting of the minimal residual disease contaminated in peripheral blood stem cell transplantation in the B-cell malignant lymphoma patients.

For sufficient collection of hemopoietic stem cells from peripheral blood for autologous peripheral blood stem cell transplantation (PBSCT), four patients with B-cell-type non-Hodgkin lymphoma (B-NHL) were examined for the appearance of circulating hemopoietic progenitors in blood (PSC) during the hemopoietic recovery phase following marrow ablative therapy in combination with or without administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF). Each patient received only chemotherapy in the first course, and rhG-CSF (1 microgram/kg/day) was administered for 14 consecutive days from the last day of the second chemotherapy. In the second chemotherapy course with rhG-CSF administration, white blood cell (WBC) counts demonstrated two peaks, and the appearance of granulocyte-macrophage precursor cells (CFU-GM) in blood at the maximum level was coincident with the second peak of WBC elevation. Erythroid precursor cells (BFU-E) were also detectable in blood after chemotherapy but the peak level was not enhanced by the use of rhG-CSF. To determine whether the minimal residual disease (MRD) cells were contaminated in PSC corrected from blood, kappa-lambda imaging (KLI) analysis was performed to detect the malignant B-cell population (mBp) before and after chemotherapy. No mBp was found in two of four patients in blood, although three of them were involved with mBp in bone marrow. The presence of mBp was detected in two patients both before and after chemotherapy, even though these cells were hardly detected morphologically, suggesting the necessity of judging for the incidence of contamination of MRD cells when collecting PSCs.

Adult↗
PubMed1992

Selective inhibition of T-cell-dependent immune responses by bisbenzylisoquinoline alkaloids in vivo.

The bisbenzylisoquinoline (BBI) alkaloids, chondocurine, tetrandrine, isotetrandrine and cepharanthine, were tested for immunosuppressive activity in mice. A plaque-forming cell (PFC) response to a T-cell-dependent antigen, sheep red blood cell, was significantly suppressed by a 7 day treatment of chondocurine or tetrandrine at 1 mg/kg/day and of isotetrandrine at 50 mg/kg/day, but not suppressed by cepharanthine treatment. The suppressive effect of chondocurine was greater when it was given after immunization rather than before or concurrently. However, it did not affect the PFC response to a T-cell-independent antigen, lipopolysaccharide. A delayed-type hypersensitivity was also suppressed by chondocurine treatment. There was no significant change in lymphocyte number and proportion of T-cell subsets in the BBI alkaloid-treated mice. These data suggest that there is selective inhibition by chondocurine and tetrandrine of the T-cell-dependent immune reactions.

Alkaloids↗