Search PubMed⌕ Search

Biomedical subjects

H Ochiai

Publications and source records attributed to H Ochiai.

At least 37 records · Page 2Linked to original sources
PubMed2001

Immunoglobulin treatment prevents congestive heart failure in murine encephalomyocarditis viral myocarditis associated with reduction of inflammatory cytokines.

We have previously shown that immunoglobulin therapy suppressed murine coxsackievirus B3 myocarditis. In the present study, we examined the effects of immunoglobulin upon murine myocarditis induced by encephalomyocarditis virus, which is not pathogenic to humans. Antiviral activity of immunoglobulin (Venilon) against encephalomyocarditis virus could not be detected in vitro. The production of cytokines was decreased in virus-infected macrophages by the treatment of immunoglobulin in vitro. Immunoglobulin (1 g/kg/day) was administered intraperitoneally to the virus-infected C3H/He mice daily for 2 weeks, beginning simultaneously with virus inoculation in experiment I and on day 14 after virus inoculation in experiment II. In experiment I, survival rate did not differ significantly between immunoglobulin-treated and untreated groups. In experiment II, survival rate was higher in immunoglobulin compared with control groups. Immunoglobulin administration suppressed the development of myocardial necrosis with T-lymphocyte infiltrates in mice not only in the acute viremic but in the chronic aviremic stages concomitantly associated with the reduction of inflammatory cytokines, i.e., tumor necrosis factor-alpha, interferon-gamma, macrophage inflammatory protein-2, and interleukin-6. Taken together, immunoglobulin therapy could have the potential to prevent congestive heart failure.

Animals↗
PubMed2001

Tranilast inhibits TGF- A1 secretion without affecting its mRNA levels in conjunctival cells.

The present study was conducted to assess the effect of Tranilast, a drug developed as anti-keloid and anti-hypertrophic scar agent, on the level of transforming growth factor- A1 (TGF- A1) mRNA, and on TGF- A1 secretion in Chang Conjunctiva cells. TGF- A1 mRNA was not detected in Chang Conjunctiva cells by Northern blot analysis, but reverse transcriptase-polymerase chain reaction (RT-PCR) analysis confirmed the presence of TGF- A1 mRNA. Tranilast, whereas the drug had no effect on the levels of TGF- A1 mRNA and cellular protein, time- and dose-dependently inhibited TGF- A1 secretion from Chang Conjunctiva cells in the enzyme-linked immunosorbent assay (ELISA) analysis. TGF- A1 is suggested to cause fibroblast proliferation, that obstructs aqueous humor filtration route after glaucoma filtration surgery. Tranilast, potentially inhibiting TGF- A1 secretion, therefore, could be a promising drug to prevent from scarring after glaucoma filtration surgery.

Adult↗
PubMed2001

Nitric oxide-mediated antitumor activity induced by the extract from Grifola frondosa (Maitake mushroom) in a macrophage cell line, RAW264.7.

We have investigated D-fraction (MDF) extracted from Grifola frondosa (Maitake mushroom) on the inducible nitric oxide synthase (iNOS)-mediated nitric oxide (NO) production in RAW264.7 (RAW) cells, a murine monocyte/macrophage cell line, with special reference to antitumor activity of MDF against human hepatoma-derived huH-1 cells. MDF could induce iNOS mRNA expression in RAW cells in a dose range of more than 30 microg/ml, but the effect of 10 microg/ml of MDF was negligible. The iNOS mRNA expression induced by 100 microg/ml of MDF was 6 hrs later, but lasted for a longer time than that of lipopolysaccharide (LPS), a representative iNOS inducer. Although iNOS mRNA levels in MDF-stimulated cells were almost equal to LPS-stimulated cells at the peak time, the cumulative amount of nitrite was only about 50% compared with that of LPS-treated cells. When huH-I cells were cultured in MDF containing media in a 24-well plate with inserted porous bottom in the presence or absence of RAW cells, the viability of huH-1 cells decreased significantly only in the presence of RAW cells in MDF dose-dependent manner. This antitumor activity of RAW cells in the presence of MDF was abolished or attenuated by the addition of L-NAME, a NOS inhibitor, confirming that this phenomenon is due to iNOS-mediated NO production by RAW cells, but not direct cytotoxic activity of MDF against huH-1 cells. These data suggest that MDF is a novel inducer for iNOS which contributes at least in part to antitumor activity of MDF.

Agaricales↗
PubMed2000

Immunoglobulin treatment ameliorates murine myocarditis associated with reduction of neurohumoral activity and improvement of extracellular matrix change.

OBJECTIVES: We examined effects of immunoglobulin on murine myocarditis induced by encephalomyocarditis virus, not pathogenic to humans, and analyzed the plasma cytokine and catecholamine levels and the changes of the extracellular matrix with or without the treatment. BACKGROUND: We have previously shown that immunoglobulin therapy suppressed murine coxsackievirus B3 myocarditis by an antiviral effect. However, it is not yet determined whether beneficial effects of immunoglobulin for myocarditis are due to antiviral effects or to other unknown effects. METHODS: Antiviral activity of human immunoglobulin (Polyglobin-N) against encephalomyocarditis virus was determined in vitro. Immunoglobulin (1 g/kg/day) was administered intraperitoneally to the virus-infected mice daily for two weeks, beginning simultaneously with virus inoculation in experiment I and on day 14 after virus inoculation in experiment II. RESULTS: Antiviral activity of immunoglobulin could not be detected in the assay of a plaque-reduction method in vitro. The in vivo study showed that immunoglobulin administration ameliorated both myocardial necrosis with interstitial fibrin deposition in experiment I and interstitial fibrosis with the improvement of ventricular remodeling in experiment II by the reduction of plasma catecholamines, interferon-alpha, and soluble intercellular adhesion molecule-1. CONCLUSIONS: Immunoglobulin therapy could suppress myocarditis associated with the improvement of extracellular matrix changes by the reduction of neurohumoral activity.

Animals↗
PubMed2000

Developmental changes in the spatial expression of genes involved in myosin function in Dictyostelium.

We analyzed the spatial expression patterns of the genes involved in myosin function by in situ hybridization at the tipped aggregate and early culmination stages of Dictyostelium. Myosin heavy chain II mRNA was enriched in the anterior prestalk region of the tipped aggregates, whereas it disappeared from there and began to appear in both upper and lower cups of the early culminants. Similarly, mRNAs for essential light chain, regulatory light chain, myosin light chain kinase A, and myosin heavy chain kinase C were enriched in the prestalk region of the tipped aggregates. However, expression of these genes was distinctively regulated in the early culminants. These findings suggest the existence of mechanisms responsible for the expression of particular genes.

Animals↗
PubMed2000

Molecular cloning and expression of aquaporin 1 [correction of aquapolin 1] (AQP1) in dog kidney and erythroblasts.

Complementary DNA of the water channel aquaporin 1 (AQP1) was cloned from dog kidney and erythroblasts. The cDNA amplified from mRNA in dog kidney was 816 bp, the same as that in bovines, but longer by 6 bp than that in humans, mice and rats. The 235-bp fragment cDNA amplified from the mRNA in dog erythroblasts, which was differentiated from peripheral blood, was completely identical to the corresponding sequence of cDNA from the dog kidney. Thus, mature red blood cells from dog may have AQP1 in their cell membranes. The amino acid sequence in dog AQP1 was 91-94% identical to that in the other species mentioned above. Dog AQP1 has six predicted transmembrane domains, two NPA motifs, one mercury-sensitive site and four consensus phosphorylation sites, the same as the other species. However, dog and bovine AQP1 have only one N-glycosylation site, while two glycosylation sites were found in human and rodent AQP1. Xenopus oocytes injected with the mRNA of the dog AQP1 exhibited high water permeability in a hyposmotic medium. Thus, dog AQP1 performs water transport the same as in the other species.

Amino Acid Sequence↗
PubMed2000

Role of MIP-2 in coxsackievirus B3 myocarditis.

Interleukin-8 (IL-8) is a chemotactic cytokine for neutrophils and lymphocytes. Macrophage inflammatory protein-2 (MIP-2) is a murine counterpart of IL-8. The present study was performed to determine the role of MIP-2 in murine myocarditis. We examined (1) the MIP-2 producing activity of Coxsackievirus B3 (CB3)-infected cultured macrophages, (2) serial plasma MIP-2 levels in CB3-induced mice by enzyme-linked immunosorbent assay (ELISA), and (3) the effects of anti-mouse MIP-2 monoclonal antibody (mAb) in vivo upon myocarditis. The production of MIP-2 increased in an infection dose- and time-dependent manner in virus-infected RAW 264.7 macrophages. Three-week-old C(3)H/He mice were inoculated with CB3. Plasma MIP-2 levels were significantly elevated in mice on days 7, 10 and 14 post-infection. Mice were injected subcutaneously with anti-MIP-2 mAb at 10 microg/day (Group 2) or 100 microg/day (Group 3) on days 0-7, and were observed until day 14. Uninfected control mice (Group 1) were injected with saline. Survival rate was higher in the anti-MIP-2-treated group (Group 3), but not in Group 2, than in the control group. Histopathological analysis revealed that cellular infiltration and myocardial necrosis with macrophage and T cell accumulation were less prominent in the anti-MIP-2 mAb-treated groups as compared to the controls. MIP-2 is an important naturally occurring inflammatory cytokine in CB3 myocarditis, and anti-MIP-2 mAb treatment may prevent the inflammatory response.

Animals↗
PubMed2000

A second functional delta5 fatty acid desaturase in the cellular slime mould Dictyostelium discoideum.

A cDNA with homology to fatty acid desaturases was selected by searching the cDNA data bank of Dictyostelium discoideum (http://www. csm.biol.tsukuba.ac.jp/cDNAproject.html) with conserved histidine box motifs. Using this sequence, genomic DNA encoding the Delta5 desaturase was amplified from the genomic DNA of D. discoideum, and its desaturase activity was confirmed by the overexpression mutation in D. discoideum and the gain-of-function mutation in yeast. The cloned cDNA is 1565 nucleotides in length, and the deduced amino-acid sequence comprised 467 amino-acid residues containing an N-terminal cytochrome b5 domain that shared 43% identity with cytochrome b5 of Oryza sativa. The whole sequence was 42% identical to the Delta5 desaturase of Mortierella alpina. This desaturase is a novel member of the cytochrome b5-containing Delta5 fatty acid desaturase. As we have already reported one other Delta5 desaturase in Dictyostelium, this organism is the first to be confirmed as having two functional Delta5 fatty acid desaturase genes. The substrate specificities of the two functional Delta5 desaturases of D. discoideum were also examined.

Amino Acid Sequence↗
PubMed2000

Primary leiomyosarcoma of the cervical spine causing spontaneous compression fracture: report of an autopsy case.

An extremely rare case of the primary leiomyosarcoma of the cervical spine presenting as a compression fracture is reported. A 69-year-old man complained of dysesthesia of both hands. A plain radiograph, computed tomography and magnetic resonance imaging of the cervical spine showed a compression fracture of the vertebral body at C7 without the formation of an obvious mass. From radiological findings, the fracture was considered to be caused by an infiltrative vertebral bone tumor. Biopsy of the tumor revealed a leiomyosarcoma, a metastatic tumor being ruled out by a systemic investigation. The patient died of pleural metastasis 6 months later, and an autopsy confirmed the primary site of the tumor as the cervical spine.

Aged↗
PubMed2000

Delayed resolution of intracranial germinoma after radiotherapy: a preliminary study of the correlation between histology and magnetic resonance imaging.

A central nervous system germinoma is curable in most cases by radiotherapy, and most of the tumor mass disappears promptly after 20-30 doses. However, some germinomas take a longer period to vanish completely from magnetic resonance imaging (MRI) or computed tomography (CT) scans. In such cases, the tumor may contain components such as teratoma. The aim of this study was to clarify the nature of the persistence of some germinomas. Five cases of histologically verified germinoma in which radiotherapy was performed to treat residual tumor were selected. The doses of focal radiotherapy and whole brain radiotherapy were 10-20 Gy and 20-34 Gy, respectively. In these cases, correlation was made between the degree of persistence of the tumor when assessed by MRI and the amount of interstitial content, as determined by histology. The histological evaluation, using hematoxylin-eosin stain, silver impregnation and Azan staining was carried out independently of clinical information. The tumor vanished soon after radiotherapy in three cases, but 3-15 months passed before the tumor completely vanished from the MRI scans in the other two cases. The histology of the cases in which the tumor disappeared rapidly was predominantly of large tumor cells and only small amounts of reticulin. However, in the persistent tumors, large amounts of reticulin and vascular components were present. Thus, it is proposed that tumors with a large parenchymal component disappear soon after radiotherapy, whereas tumors composed mainly of interstitial component persist. Long-standing enhancement seen on MRI or CT scans of patients with an intracranial germinoma is indicative of a large amount of interstitial component in the tumor.

Adolescent↗
PubMed2000

Brain surface ependymoma.

A case of brain surface ependymoma is reported here. A 41-year-old woman presented with weakness of the right upper limb. Magnetic resonance imaging revealed a left fronto-parietal cystic tumor with a calcified mural nodule. Total removal of the tumor was performed. This tumor was located within the surface portion of the fronto-parietal parenchyma and was sharply demarcated from the surrounding brain tissue, and there was no continuity with the ventricles. Histological examination of this tumor showed monotonous proliferation of tumor cells with moderate cellularity and occasional mitoses, forming true ependymal rosettes and perivascular pseudorosettes with fibrillary background. A clear cell component resembling oligodendroglioma was partly noted. The tumor cells showed positive immunoreaction for glial fibrillary acid protein and vimentin.

Adult↗
PubMed2000

Therapeutic effect of anti-macrophage inflammatory protein 2 antibody on influenza virus-induced pneumonia in mice.

We investigated the effect of anti-macrophage inflammatory protein 2 immunoglobulin G (aMIP-2 IgG) on the progression of influenza virus-induced pneumonia in mice. When mice were infected with a mouse lung-adapted strain of influenza A/PR/8/34 virus by intranasal inoculation, neutrophil counts in the bronchoalveolar lavage fluid (BALF) increased in parallel with the kinetics of MIP-2 production, which peaked 2 days after infection. After intracutaneous injection of a dose of 10 or 100 microg of aMIP-2 IgG once a day on days 0 and 1, neutrophil counts in BALF on day 2 were reduced to 49 or 37%, respectively, of the value in the control infected mice administered anti-protein A IgG. The antibody administration also improved lung pathology without affecting virus replication. Furthermore, by prolonged administration with a higher or lower dose for up to 5 days, body weight loss became slower and finally 40% of mice in both treatment groups survived potentially lethal pneumonia. These findings suggest that MIP-2-mediated neutrophil infiltration during the early phase of infection might play an important role in lung pathology. Thus, MIP-2 was considered to be a novel target for intervention therapy in potentially lethal influenza virus pneumonia in mice.

Animals↗
PubMed2000

Enhanced expression of inducible nitric oxide synthase by Juzen-taiho-to in LPS-activated RAW264.7 cells, a murine macrophage cell line.

We have investigated the effect of Juzen-taiho-to (TJ-48) on inducible NO synthase (iNOS) expression and nitric oxide (NO) production in RAW264.7 cells, a murine macrophage cell line. TJ-48-lipopolysaccharide (LPS) combination induced iNOS mRNA expression earlier, stronger and remained longer that paralleled but with a higher NO production compared to LPS stimulation. TJ-48 itself showed no inducible effect either on NO production or iNOS mRNA expression. This phenomenon could be considered to contribute, at least in part, to the beneficial effects of TJ-48 through the iNOS-mediated activation of biodefense mechanism.

Animals↗
PubMed2000

Acute eosinophilic myocarditis in a young woman.

The first stage of eosinophilic myocarditis is called the necrotizing phase. This stage of eosinophilic myocarditis of unknown cause is often fulminant and rapidly fatal, occurring predominantly in males. Here, we report a case of eosinophilic myocarditis in the acute necrotizing phase occurred without known cause in a 23-year-old Japanese female. Severe diffuse hypokinesis of the left ventricular wall motion (ejection fraction 19.3%), significant concentric edematous thickening of the left ventricular wall (20.1 mm in diastole) and a moderate amount of pericardial effusion (10 mm wide echo free space posteriorly) were revealed by echocardiography. Eosinophils were observed and degranulated eosinophilic cationic proteins were stained with antibody against eosinophilic cationic proteins (EG2) in the myocardial specimens obtained by myocardial biopsy. In spite of its severity, the disease resolved promptly with steroid therapy.

Acute Disease↗
PubMed2000

Isolation and measurement of carbonic anhydrase isoenzymes in erythrocytes of dogs.

OBJECTIVE: To purify canine carbonic anhydrase (CA) isoenzymes CA-I and CA-II and to determine concentrations of CA-I and CA-II in erythrocytes of Beagles and dogs native to Japan. SAMPLE POPULATION: Blood samples from 116 Beagles, including 24 pregnant Beagles, and blood samples from 29 dogs native to Japan. PROCEDURE: Canine CA-I and CA-II were purified by use of column chromatography. Concentrations of CA-I and CA-II in erythrocytes of dogs were determined, using an ELISA. RESULTS: Mean (+/- SD) concentrations of CA-I and CA-II in erythrocytes of Beagles were 3.21+/-0.86 and 1.63+/-0.39 mg/g of Hb, respectively. Mean concentration of CA-I was greater in male Beagles than female Beagles. In contrast, mean concentration of CA-II was greater in female Beagles than male Beagles. Furthermore, concentration of CA-II was greater in pregnant female Beagles than male or nonpregnant female Beagles. Mean concentrations of CA-I and CA-II in erythrocytes of dogs native to Japan were 11.03+/-4.39 and 3.29+/-0.91 mg/g of Hb, respectively. Mean concentration of CA-I was greater in male dogs from Japan than female dogs from Japan. CONCLUSIONS AND CLINICAL RELEVANCE: The ELISA used in this study proved to be precise and sensitive for determining CA-I and CA-II concentrations in dogs. The ELISA may enable study of changes in isoenzymes associated with hereditary or metabolic disorders of blood or other body fluids, using only a small sample. Measurement of the concentrations of CA isoenzymes in dogs may be of diagnostic value.

Animals↗
PubMed2000

[L-dopa effective parkinsonism appeared after shunt revision of the aqueductal stenosis: report of two cases].

We present a two cases of parkinsonism that appeared after shunt revision in obstructive hydrocephalus patients. Case 1 was a 59-year-old man and case 2 was a 32-year-old woman. Parkinsonism appeared in both cases after 3 or 4 shunt revisions within a period of three months. Treatment with bromocriptine, amantadine and L-dops had no effect, but the parkinsonism dramatically improved with administration of L-dopa. It was thought that repeated dilatation and collapse of the third ventricle in a short period of time might have caused concussion of the nigrostriatal pathway, resulting in reversible function loss of the nigrostriatal pathway.

Adult↗
PubMed2000

Single genotype of measles virus is dominant whereas several genotypes of mumps virus are co-circulating.

We have reported that in Japan measles virus strains have been classified into three distinct different genotypes (C1, D3 and D5) under the new international genotype classification since 1984. Similarly, mumps virus strains have been divided into two genotypes with three subtypes (B1, B2, B3, and D) under the proposed international classification since 1976. To differentiate these genotypes we developed a restriction fragment length polymorphism assay in the hemagglutinin (H) region for measles virus and in the hemagglutinin-neuraminidase (HN) region for mumps virus to facilitate the expanded molecular epidemiology. In the Sapporo 1995/1996 measles outbreak, all 26 strains were classified as D5. Among 32 samples from patients with measles from 1994 to 1997 in Tokyo, 28 were identified as D5 and four were D3; these D3 strains were ascertained as a same hospital acquired infection. Among 45 strains obtained in the Tokyo 1999 outbreak, 38 were D3 and the remaining seven were D5. The dominant genotype of measles in Tokyo has replaced from D5 to D3 similar to the Chicago1/89 strain. We obtained 220 samples from patients with mumps from 1993 to 1997 and they were classified into one strain of B1, 14 strains of B2, 151 strains of B3, and 54 strains of D. Therefore, we suggest that two or three subtypes of mumps virus are co-circulating with a different geographic pattern in genotype distribution, whereas a single measles virus genotype is dominantly observed, showing different epidemiological patterns.

Amino Acid Sequence↗