Biomedical subjects

N Ohara

Publications and source records attributed to N Ohara.

At least 127 records · Page 7Linked to original sources

PubMed1995

An internal control for the rapid detection of mycobacteria by amplification of a segment of the gene encoding alpha antigen.

The internal control of DNA for the rapid detection of mycobacteria by PCR is described. The 1100bp fragment for internal control was produced from Streptomyces lividans DNA with the primers used for the rapid detection of mycobacteria by PCR. The amplified reaction consequently produced two products with 782bp for mycobacteria and 1100bp for the internal control extracted from all mycobacterial DNAs containing internal control so far examined. The 1100bp amplified fragment proved to be useful as an internal control with the same primer-binding sequence for the detection of mycobacteria.

Antigens, Bacterial↗

PubMed1995

[The role of some cellular components of bacterial parasites in determining the incidence of tuberculosis: studies on mycobacterial antigens, with special reference to mycobacterial immunoreactive ribosomal and secreted proteins].

Tuberculosis remains as major disease, affecting more than 20 million people. The elimination of the disease with vaccination, rapid diagnosis, and and efficient therapy is an important objective of our study. To realize the objective, the characterization of antigens is essential. We have chosen two kinds of antigens for our study, the ribosomal antigens and and an antigenic proteins secreted by mycobacteria. The biochemical and immunological characterization of ribosomal fraction was carried out. Ribosomal proteins were purified and assessed for DTH reaction. The N-terminal amino acids sequences were determined. Total structures of S19, S7 and S12 in 30S and L7/L12 in 50S subunits were elucidated. L7/L12 had 66% homology with analogue from S. griseus which showed GTPase activity in protein synthesis. This protein was secreted in culture medium and induced strong DTH. Secreted antigenic proteins are of great interest for us. Secreted antigens may be recognized rapidly by immune system and therefore may induce rapid and high level immune response. It is also expected that it may contain protective antigens, since live BCG protect disease more efficiently than heat killed BCG. We have determined and published the total structure of four proteins (MPB64, MPB70, MPB57 and alpha antigen). We attempted to utilize this antigen for the diagnosis and the design of vaccine. The structures of alpha antigens from M. avium, M. intracellulare, M. scrofulaceum, M. kansasii and BCG were determined and its potential for application to diagnosis was presented. Using the operon of M. kansasii, alpha antigen and V3 region of HIV-1 were expressed by recombinant BCG which induced CTL in mice.

Animals↗

PubMed1994

Cloning and sequencing of the groESL homologue from Porphyromonas gingivalis.

The homologue of groESL from Porphyromonas gingivalis was cloned and sequenced. Nucleotide sequencing suggested an operon containing two open reading frames (ORFs) homologous to groESL operon of Escherichia coli. The upstream ORF consisted of 267 bp corresponding to 89 amino acid residues. The downstream ORF consisted of 1635 bp corresponding to 545 amino acid residues.

Amino Acid Sequence↗

PubMed1994

Primary osteosarcoma of the cerebrum with immunohistochemical and ultrastructural studies: report of a case.

A 57-year-old woman with primary intracerebral osteosarcoma is reported. The tumor was identified by computed tomography as a mass with hemorrhage in the right parietal lobe. The surgical and pathological examinations confirmed an osteosarcoma of intracerebral origin. She suffered from repeated local recurrence of the tumor and died about 1 year after the onset. The pathological findings showed features of osteoblastic osteosarcoma with numerous osteoclast-like multinucleated giant cells. Immunohistochemically, tumor cells were positive for vimentin, and partially for actin. Multinucleated giant cells were reactive with vimentin and CD68 antibodies. Ultrastructurally, tumor cells were rich with rough endoplasmic reticulum. These findings are consistent with the histological features of skeletal or extraskeletal osteosarcoma. This is the third case of primary intracerebral osteosarcoma reported in the literature and the first one analyzed ultrastructurally.

Brain Neoplasms↗

PubMed1994

Cytotoxic T lymphocyte response in mice induced by a recombinant BCG vaccination which produces an extracellular alpha antigen that fused with the human immunodeficiency virus type 1 envelope immunodominant domain in the V3 loop.

The host immune response of cell-mediated immunity, particularly that of cytotoxic T lymphocytes (CTLs), is a major immune defence mechanism which may provide resistance to a human immunodeficiency virus type 1 (HIV-1) spread leading to acquired immune deficiency syndrome (AIDS). To prevent the accompanying activity of HIV-1 proteins responsible for the loss of helper T-lymphocyte function, it is crucial to develop a live attenuated recombinant vaccine expressing only T- or both T- and B-cell epitopes. Here, we examined the expression of the HIV-1 Env protein V3 region (15 amino acids from Arg315 to Lys329) in Mycobacterium bovis BCG as a fused form with an extracellular alpha antigen of Mycobacterium kansasii. Balb/c mice inoculated with this recombinant BCG (rBCG), rapidly induced V3 peptide-specific CTLs. Target cell lysis was restricted to the murine class I major histocompatibility complex, H-2d. A similar CTL response was also elicited after Balb/c mice were immunized with the same rBCG even when pre-inoculated with non-recombinant BCG. Thus, the rapid induction of HIV-1-specific CTLs indicates that this vaccine may be a therapeutic approach to preventing progression to AIDS.

AIDS Vaccines↗

PubMed1994

HTLV-II non-integrated malignant lymphoma induction in Japanese white rabbits following intravenous inoculation of HTLV-II-infected simian leukocyte cell line (Si-IIA).

Lymphoma induction in rabbits by an unknown factor derived from an HTLV-II-producing simian (Cynomolgus) leukocyte cell line (Si-IIA) is reported. Thirteen of 17 male Japanese white rabbits (76%) inoculated intravenously with Si-IIA cells developed malignant lymphoma including Hodgkin-like lymphoma between 62 and 167 days after inoculation. Histologically, there was extensive diffuse or nodular infiltration of either large cell type or mixed type lymphoma cells in many organs, frequently involving the spleen, liver, lymph nodes and kidneys, and less frequently the thymus, bone marrow, lungs, heart, skin and gastrointestinal tract. Hodgkin-like lymphoma was also observed in two rabbits. Chromosomal analysis of five cell lines established from tumor-bearing rabbits revealed the male rabbit karyotype. The immunophenotype of these tumor cells was usually T-cell (CD5+ or -, RT1+, RT2+ or -, CD45+, CD4-, RABELA- and MHC class II-DQ+) except for Hodgkin-like lymphoma cells which expressed only CD45. However, integration of the HTLV-II provirus genome could not be demonstrated in the tumor tissues or any of the rabbit cell lines by polymerase chain reaction or Southern blot analysis. Moreover, no lymphoma was induced by inoculation of HTLV-IIC, MOT (other HTLV-II-producing human cell lines) or TALL-1 (control). Two of four rabbits injected with cell-free pellets from Si-IIA cultures died of malignant lymphoma (15-20 days). Five irradiated rabbit cell lines were inoculated but only one (Ra-SLN) induced lymphoma in 1 of 3 rabbits at 27 days. Neither Herpesvirus saimiri nor Herpesvirus ateles (simian oncogenic viruses) was detected in Si-IIA cells by immunofluorescence testing. These data suggest that the high rate of lymphoma induction in rabbits may be caused not by only HTLV-II or well known simian oncogenic viruses, but rather by an unknown passenger agent derived from Si-IIA or HTLV-IIA, with which Si-IIA was established.

Animals↗

PubMed1994

Cloning, sequencing and expression in Escherichia coli of the gene for alpha antigen from Mycobacterium scrofulaceum.

The gene for the extracellular alpha antigen of Mycobacterium scrofulaceum (S-alpha) was cloned by using the alpha antigen gene fragments of Mycobacterium bovis BCG as probes. The complete nucleotide sequence was determined. The gene was expressed in Escherichia coli. The gene encodes 330 amino acids, including 40 amino acids for the signal peptide, followed by 290 amino acids for the mature protein. The deduced amino acid sequences were highly homologous to the alpha antigen of the species of other mycobacteria. Interestingly, the alpha antigens of MAIS complex (Mycobacterium avium-Mycobacterium intracellulare-M. scrofulaceum) were closely homologous even at the C-terminal regions which were variable among those of M. bovis BCG, Mycobacterium leprae and Mycobacterium kansasii.

Amino Acid Sequence↗

PubMed1994

Aberrant expression of the monocyte/macrophage phenotype in a human T cell line immortalized by HTLV-I and an adult T cell leukemia/lymphoma cell line.

An HTLV-I-immortalized human T cell line (JP-2), a N-methyl-N'-nitro-N-nitrosoguanidine-treated JP-2 line (JP-2T), and an adult T cell leukemia cell line (ATL-1T) were examined morphologically and phenotypically. All of these cell lines expressed some T cell markers, including CD4, and showed rearrangement of T cell receptor (TCR) genes, but they lacked CD3 and TCR antigens and expressed some myelomonocytic markers (CD68, HL-21, CD15, CD16). JP-2 cells grew in suspension, but JP-2T and ATL-1T cells, which mostly adhered to the surface of culture vessels, showed macrophage-like morphological features and expressed more monocyte/macrophage markers (lysozyme, alpha 1-antitrypsin) and fibronectin. ATL-1T cells transplanted into SCID mice lost the macrophage features. These results suggest that HTLV-I infected T cells can express some macrophage features and that these cells may provide a model that will be useful in elucidating the phenotypic variability of T cell lymphomas.

Animals↗

PubMed1994

Inflammatory pseudotumor of the urinary bladder with an aberrant expression of cytokeratin.

A case of inflammatory pseudotumor of the urinary bladder in a 47 year old Japanese male patient is presented. Inflammatory pseudotumor of the urinary bladder is a benign but rare proliferative lesion of the submucosal stroma, easily mistaken for a malignant neoplasm. Based on the clinical diagnosis of bladder cancer by cystoscopy and magnetic resonance imaging (MRI), urologists started chemotherapy before results of the histological report were available which described inflammatory pseudotumor on the biopsy. Biopsied materials showed marked proliferation of irregularly bundled spindle cells, varied in size and shape and separated in severe loose myxoid stroma with moderate infiltration of the inflammatory cells and capillary proliferations. At a glance, these findings resemble the sarcomatous pattern. However neither severe nuclear atypism nor atypical mitoses were present. Immunohistochemically, these spindle cells, which were positive for vimentin and alpha-smooth muscle actin, showed a diffuse aberrant expression of cytokeratin. Some of them were positive for phosphotungstic acid hematoxylin. Electron microscopy revealed only the fibroblasts. No recurrence has been observed for 10 months. These findings indicate that inflammatory pseudotumor is a benign mesenchymal lesion that must be discriminated from true sarcoma to avoid subjecting the patient to unnecessary therapy. Only careful histological examination can enable a successful diagnosis.

Granuloma, Plasma Cell↗

PubMed1994

Chronic biliary obstruction induces pulmonary intravascular phagocytosis and endotoxin sensitivity in rats.

Endotoxin sensitivity varies among animal species and appears to correlate with the presence of pulmonary intravascular macrophage (PIM). In rats, which lack PIM, we investigated the hypothesis that chronic cholestatic liver injury leads to induction of PIM and endotoxin sensitivity. Rats were randomized to either common bile duct ligation (BDL) or sham-surgery and studied at 1 wk (acute cholestasis), 2 wk (cholestasis, early cirrhosis), and 4 wk (cholestasis, established cirrhosis) after surgery. Intravascularly injected fluorescent latex microspheres (1 micron diameter) were taken up by large phagocytic cells in lung parenchyma of BDL rats (at 2 and 4 wk), while no uptake was observed in lungs from control rats. Electronmicroscopy revealed accumulation of large, mononuclear, macrophage-like cells containing ingested latex particles within the pulmonary capillaries. Pulmonary intravascular phagocytosis, as reflected in lung uptake of 99mTc microaggregated albumin (Microlite, mean particle diameter = 1 micron), averaged 0.7 +/- 0.1% (mean +/- SEM) of total injected dose in 13 control rats and progressively increased with time after BDL (1 wk, 1.7 +/- 0.2%; 2 wk, 10.0 +/- 3.0%; 4 wk 35.1 +/- 5.9%). Rats with biliary cirrhosis were markedly sensitive to the lethal effects of low dose endotoxin and demonstrated marked lung edema at the time of death. Furthermore, the lung uptake of intravascular 125I-lipopolysaccharide was increased five-fold in cirrhotic rats. We conclude that chronic biliary obstruction leads to the induction of pulmonary intravascular phagocytes and enhances endotoxin sensitivity in rats. Pulmonary intravascular phagocytosis in patients with advanced cirrhosis may account for their increased susceptibility to sepsis-induced adult respiratory distress syndrome.

Animals↗

PubMed1994

An acidic polysaccharide with immunological activities from the root of Paeonia lactiflora.

An acidic polysaccharide, called peonan PA, was isolated from the root of Paeonia lactiflora PALLAS. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 6.0 x 10(4). Peonan PA is composed of L-arabinose: D-galactose: D-galacturonic acid in the molar ratio of 2:1:10, in addition to small amounts of O-acetyl groups and peptide moieties. About forty percent of the hexuronic acid residues in peonan PA exist as methyl esters. Reduction of carboxyl groups, methylation analysis, lithium degradation and nuclear magnetic resonance studies indicated that its main structural features involve both alpha-1,5-linked L-arabino-beta-3,6-branched D-galactan type and alpha-1,4-linked D-galacturonan type structural units. The polysaccharide exhibited remarkable reticuloendothelial system-potentiating activity in a carbon clearance test and considerable anti-complementary activity.

Animals↗

PubMed1994

The core structure of ginsenan PA, a phagocytosis-activating polysaccharide from the root of Panax ginseng.

Controlled Smith degradation and limited hydrolysis of ginsenan PA, the main phagocytosis-activating polysaccharide isolated from the root of Panax ginseng C. A. Meyer, were performed. The reticuloendothelial system-potentiating and anti-complementary activities of the degradation products were investigated. Methylation analysis of the primary and secondary Smith degradation products indicated that the core structural features of ginsenan PA include a backbone chain mainly composed of beta-1,3-linked D-galactose. Almost half of the galactose units in the backbone carry side-chains composed of beta-1,6-linked D-galactosyl residues at position 6. Further 3,6-branching of D-galactose units was observed in a part of the side-chains. alpha-L-Arabinose units are connected mainly to the core galactose moieties via position 6. Removal of most of the arabinose units had a considerable effect on immunological activity.

Animals↗

PubMed1994

Two acidic polysaccharides having reticuloendothelial system-potentiating activity from the raw root of Rehmannia glutinosa.

Two acidic polysaccharides, called rehmannan FS-I and rehmannan FS-II, were isolated from the raw root of Rehmannia glutinosa LIBOSCHITZ. They were homogeneous on electrophoresis and gel chromatography, and their molecular masses were estimated to be 5.8 x 10(4) and 6.6 x 10(4), respectively. Rehamannan FS-I is composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 68:40:4:84:3; rehmannan FS-II is composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid in the molar ratio of 18:15:4:33, in addition to small amounts of O-acetyl groups. About two-thirds (rehmannan FS-I) and about one half (rehamannan FS-II) of the hexuronic acid residues exist as methyl esters. Methylation analysis of the carboxyl-reduced derivatives and nuclear magnetic resonance studies indicated that their structural features include mainly both arabino-3,6-galactan and rhamno-galacturonan type structural units. Both polysaccharides showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test.

Animals↗

PubMed1994

Characterization of an acidic polysaccharide with immunological activities from the tuber of Pinellia ternata.

An acidic polysaccharide, called pinellian PA, was isolated from the tuber of Pinellia ternata Breit. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 11.8 x 10(4). Pinellian PA is composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 5:15:1:3:3, in addition to small amounts of O-acetyl groups and peptide moieties. Reduction of carboxyl groups, methylation analysis and nuclear magnetic resonance studies show that the core structural features include a backbone chain composed of beta-1,3-linked D-galactose units. Some of the galactose units in the backbone carry beta-1,6-linked D-galactosyl side-chains at position 6. Pinellian PA produces significant potentiation of the reticuloendothelial system, as shown by a carbon clearance test, and also exhibits potent anti-complementary activity.

Animals↗

PubMed1994

A glucan with immunological activities from the tuber of Alisma orientale.

A glucan, called alisman SI, was isolated from the tuber of Alisma orientale Juzepcz. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was 1.1 x 10(4). It is composed solely of D-glucose. Methylation analysis, nuclear magnetic resonance and enzymic degradation studies indicated that it has a high-branched glucan type structure mainly composed of alpha-1,4-linked D-glucopyranosyl residues with partially alpha-1,6-linked units and both 3,4- and 4,6-branching points. The polysaccharide exhibited significant reticuloendothelial system-potentiating activity in a carbon clearance test, as well as a pronounced anti-complementary activity.

Carbohydrate Sequence↗

PubMed1994

Characterization of an acidic polysaccharide having immunological activities from the tuber of Alisma orientale.

An acidic polysaccharide, called alisman PII, was isolated from the tuber of Alisma orientale Juzepcz. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 5.25 x 10(4). It is composed of L-arabinose:D-galactose:D-glucuronic acid in the molar ratio of 4:9:2, in addition to some of O-acetyl groups. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and controlled Smith degradation indicated that the core structural features include a backbone chain composed of beta-1,3-linked D-galactose units. Some of the galactose units in the backbone carry beta-D-galactosyl side chains at position 6. Both alpha-1,5-linked L-arabinosyl side chains and terminal beta-D-glucuronic acid residues are linked to the core galactan units. Alisman PII showed significant potentiation of the reticuloendothelial system using a carbon clearance test and also potent anti-complementary activity.

Animals↗

PubMed1994

A glucan having reticuloendothelial system-potentiating and anti-complementary activities from the tuber of Pinellia ternata.

A glucan, called pinellian G, was isolated from the tuber of Pinellia ternata BREIT. It was homogenous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 1.5 x 10(4). It is composed solely of D-glucose, in addition to a few O-acetyl groups. Methylation analysis, nuclear magnetic resonance and enzymic degradation studies indicated that it is a branched glucan mainly composed of alpha-1,4-linked D-glucopyranose residues with partially alpha-1,3-linked units and 4,6-branching points. The glucan showed significant reticuloendothelial system-potentiating activity in a carbon clearance test, as well as pronounced anti-complementary activity.

Acetylation↗

PubMed1994

Characterization of a novel heteroglucan from the rhizome of Cnidium officinale exhibiting high reticuloendothelial system-potentiating and anti-complementary activities.

A novel beta-heteroglucan, called cnidirhan SIIA, was isolated from the rhizome of Cnidium officinale MAKINO. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was more than 1 x 10(7). It was composed of D-glucose, D-galactose and L-arabinose in the molar ratio of 85:5:8, in addition to small numbers of O-acetyl groups. Methylation analysis and nuclear magnetic resonance studies indicated its main structural features composed of beta-1,6-linked D-glucopyranosyl residues with both 3,6- and 4,6-branching points. In addition, it has both beta-1,4-linked L-arabinopyranosyl and beta-1,6-linked D-galactopyranosyl residues. The polysaccharide showed very pronounced reticuloendothelial system-potentiating activity in a carbon clearance test, as well as a marked anti-complementary activity.

Adult↗