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H Ochiai

Publications and source records attributed to H Ochiai.

At least 199 records · Page 11Linked to original sources
PubMed1989

Isolation and characterization of low- and high-metastatic clones from murine RCT (Radiological, Chiba, and Toyama) sarcoma.

We have established low- and high-metastatic clones, named RCT(-) and RCT(+) cells, respectively, from the RCT (Radiological, Chiba, and Toyama) sarcoma spontaneously developed in a C3H/He male mouse by the limiting-dilution method in vitro or by the combination of the lung passages and limiting-dilution methods. After 20 serial passages in vitro, the metastatic potential of each clone did not alter. Morphologically, both cells were spindle-shaped, but RCT(+) cells were slightly thicker and larger than RCT(-) cells. The organization of actin-containing filaments was slightly poorer in RCT(+) cells than that in RCT(-) cells. Marked differences were observed in their growth characteristics and adhesiveness to plastic or collagen-coated surfaces, that is, RCT(+) cells grew more slowly but could adhere more rapidly and firmly to the surfaces than RCT(-) cells. RCT(+) cells were agglutinated by all lectins used but several lectins could not agglutinate RCT(-) cells. These results could be a reflection of the difference in oligosaccharide residues on the surface of each cell and, in part, might reflect the difference in organization of the actin-containing filaments that regulate the mobility of lectin receptors. No significant difference between these cell clones was noted in their sensitivity to natural-killer-cell-mediated cytotoxicity in vitro. RCT(-) and RCT(+) cells are considered to be the most useful experimental model for the study of the certain sarcomas.

Animals↗
PubMed1989

Electron-microscopic immunocytochemistry of neuropeptide Y immunoreactive innervation of vasopressin neurons in the paraventricular nucleus of the rat hypothalamus.

The neuropeptide Y (NPY) immunoreactive synaptic input to neurons containing neurophysin II (NP II), the carrier protein of vasopressin (VP), was observed in the paraventricular nucleus (PVN) of the rat hypothalamus by double-labeling immunocytochemistry combining the preembedding peroxidase-antiperoxidase (PAP) method with the postembedding immunogold staining method at the electron-microscopic level. NPY-like immunoreactivities were detected by the PAP method in the dense granular vesicles (70-100 nm in diameter) in the immunoreactive presynaptic axon terminals. NP II-like immunoreactive large neurosecretory granules labeled with gold particles were found in the neurons receiving synaptic input of the NPY-like immunoreactive terminals. This suggests that NPY may be a neurotransmitter or neuromodulator and that NPY neurons may, through synaptic contacts, regulate the secretion of VP neurons.

Animals↗
PubMed1989

[Relationship between left atrial diameter and cardiac function in myocardial infarction--assessment of left ventricular end-diastolic pressure by the left atrial index].

To study the assessment of cardiac function in acute myocardial infarction (AMI), we measured left atrial diameter, left ventricular end-diastolic pressure (LVEDP), pulmonary capillary wedge pressure (PCWP), ejection fraction (EF) in 20 patients with acute myocardial infarction. Left atrial diameter was measured using echocardiography and was expressed as left atrial index (LAI, mm/m2) dividing by body surface area. LAI in AMI was 21.3 +/- 2.7 mm/m2 and significantly larger than LAI in normal subject (19.9 +/- 2.0 mm/m2) (p less than 0.05), In AMI, LVEDP was 13.3 +/- 3.4 mmHg, PCWP was 9.0 +/- 2.8 mmHg and EF was 52.3 +/- 14.8%, Relationship (r value) between LAI and LVEDP (r = 0.70, p less than 0.001, y = 0.87 x-5.4 x; LAI, y; LVEDP) was greater than PCWP and LVEDP (r = 0.60, p less than 0.01). LVEDP calculated from LAI using this method was directly measured LVEDP directly measured +/- 2.4 mmHg. In 9 patients, LAI was larger than 20.9 mm/m2, in 8 patients of them LVEDP was higher than 13 mmHg. In 11 patients LAI was smaller than 20.9 mmHg, only in 2 of them LVEDP was lower than 13 mmHg. It concluded that sensitivity was 88.9%, specificity was 81.8%, accuracy was 85.0%. Relationship between LAI and PCWP (r = 0.30), LAI and EF (r = -0.36) were not significant. We can measure LAI repeatedly in AMI non-invasively, and predict LVEDP. Thus, the measurement of LAI is useful in treatment of AMI.

Adult↗
PubMed1988

Ultrastructural demonstration of the catecholaminergic innervation of vasopressin neurons in the paraventricular nucleus of the rat by double-labeling immunocytochemistry.

The catecholaminergic innervation of vasopressin (VP) neurons in the paraventricular nucleus (PVN) of the rat was studied at the electron microscopic level by double-labeling immunocytochemistry combining the preembedding peroxidase-antiperoxidase method with the postembedding immunogold staining method. Tyrosine hydroxylase-like immunoreactive nerve terminals were found to establish synapses with neurophysin II-like immunoreactive neuronal perikarya and their processes. This provides morphological evidence for catecholaminergic control of the release of VP, at the PVN level.

Animals↗
PubMed1988

Application of the single radial complement fixation test for serodiagnosis of influenza, respiratory syncytial, mumps, adeno type 3, and herpes simplex type 1 virus infections.

A stabilized modification of the single radial complement fixation (SRCF) test in gel was developed for detecting various virus antibodies. The principle of the test is based on the use of a single-stage procedure with an agarose plate containing virus antigens and antibody-coated erythrocytes, and thin plastic film coated with complement. By filling the wells in the agar plate with a 1:4 diluted heat-inactivated sera and covering the agar surface with a complement film, a zone of unlysed cells surrounded by a hemolytic area appears after incubation overnight at 4 degrees C and then for 1-2 h at 37 degrees C, depending on the antibody titers. The SRCF antibody titer is calculated numerically from the square of the diameter of the unlysed cell zone. The stability of reagents could be significantly improved using thin complement film and several stabilizers. When this test was used for serodiagnosis of influenza, respiratory syncytial (RS), mumps, adeno virus type 3 and herpes simplex type 1 virus infections (using a total of 400 sera), excellent correlations were demonstrated for antibody titers between conventional complement fixation (CF) and SRCF titers. Furthermore, the expression of antibody titer as an SRCF unit with consecutive value, produced results sensitive to fluctuations in the antibody titers. The simplicity of the procedure, stability of the reagents, and excellent correlation with the conventional CF test might make this a useful test for routine serodiagnosis and seroepidemiological survey of various virus infections.

Adenovirus Infections, Human↗
PubMed1988

Detection of herpes simplex virus type 1 in herpetic ocular diseases by DNA-DNA hybridization using a biotinylated DNA probe.

A diagnostic hybridization assay for detecting herpes simplex virus type 1 (HSV-1) in ocular specimens was developed using cloned viral DNA as a probe. This hybridization assay is based on visualizing a biotinylated probe that is hybridized to the target DNA by a streptavidin/alkaline phosphatase system. The time required for performing this assay system is only two days. This assay system could detect a probe which had been hybridized to as little as 1 pg of homologous DNA and did not cross-react with DNA of other human herpes viruses except that of herpes simplex virus type 2 (HSV-2) which showed weak cross-reactivity. The assay system was applied to experimental keratitis in albino rabbits and clinical specimens. In experimental keratitis in rabbits it was possible to detect HSV-1 DNA in the eye swab samples at least until the ninth day after virus inoculation. Five clinical specimens collected from patients with corneal ulcer or blepharitis contained HSV-1 DNA in spite of the failure of demonstration of viral antigen and/or virus isolation in two cases.

Animals↗
PubMed1988

Relation of H-2 expression on murine RCT(+) sarcoma cells to lung colonization and sensitivity to NK cells.

Murine RCT(+) sarcoma cells were sorted using a fluorescence-activated cell sorter with regard to the expression of H-2 antigens and then an increased H-2-expressing subclone was established, and named RCT(+)H-2+. The experimental metastasis of RCT(+) cells was compared with that of RCT(+)H-2+ cells by counting pulmonary colonies on the 21st day after i.v. inoculation of tumor cells (5-10 x 10(4)/mouse). When mice were inoculated with RCT(+) cells, mean numbers of pulmonary colonies were 2.1(range 0-6), 2.8(range 0-7) using 5 x 10(4) and 1 x 10(5) cells, respectively. On the other hand, in the mice inoculated with RCT(+)H-2+ cells, figures obtained were 7.0(range 4-16), 31.9(range 13-79), using 5 x 10(4) and 1 x 10(5) cells, respectively. The survival rate of RCT(+)H-2+ cells was higher than that of RCT(+) cells, when this was assayed in the early stage after i.v. injection of 51Cr-labeled cells (1 x 10(5) cells/mouse). In addition, RCT(+)H-2+ cells were more resistant than RCT(+) cells to lysis mediated by natural killer cells. These data suggest that an increase in metastatic ability was paralleled by an increase in the H-2 antigen expression and a decrease in sensitivity to the natural killer cells.

Animals↗
PubMed1988

In vitro and in vivo antiviral activity of scopadulcic acid B from Scoparia dulcis, Scrophulariaceae, against herpes simplex virus type 1.

The antiviral activity of five diterpenoids isolated from Scoparia dulcis L., Scrophulariaceae, was examined in vitro against herpes simplex virus type 1. Among these compounds, only scopadulcic acid B was found to inhibit the viral replication with the in vitro therapeutic index of 16.7. The action of scopadulcic acid B was not due to a direct virucidal effect or inhibition of virus attachment to host cells. Single-cycle replication experiments indicated that the compound interfered with considerably early events of virus growth. The influence of scopadulcic acid B on the course of the primary corneal herpes simplex virus infection was investigated by means of a hamster test model. When the treatment was initiated immediately after virus inoculation, scopadulcic acid B, when applied orally or intraperitoneally, effectively prolonged both the appearance of herpetic lesions and the survival time at the dose of 100 and 200 mg/kg per day.

Animals↗
PubMed1988

Monoclonal antibodies against discoidin I and discoidin II of the cellular slime mold, Dictyostelium discoideum.

The preparation and properties of monoclonal antibodies against carbohydrate-binding proteins (discoidin I and discoidin II) in the cellular slime mold, Dictyostelium discoideum are described. Monoclonal antibody (mAb) ndI,II-1 bound both discoidins I and II specifically. mAb nI-1 and mAb dI-1 bound only discoidin I but their binding specificities were different: nI-1 recognized the native form and dI-1 the denatured form. mAb dII-1 bound only denatured discoidin II. In preliminary work mAbs dII-1 and nI-1 were found to be useful for localizing discoidins I and II immunohistochemically.

Antibodies, Monoclonal↗
PubMed1988

Glutamine synthetase from a cyanobacterium, Phormidium lapideum: purification, characterization, and comparison with other cyanobacterial enzymes.

Glutamine synthetase has been purified to homogeneity from cell extracts of a non-N2-fixing filamentous cyanobacterium, Phormidium lapideum. The subunit molecular weight of the enzyme was determined as about 59,000 by sodium dodecyl sulfate gel electrophoresis. Electron micrographs of the Phormidium enzyme revealed a two-layered structure of regular hexagons (12 subunits per molecule), which markedly resembles the three-dimensional polypeptide backbone structure of the Salmonella typhimurium glutamine synthetase established by X-ray crystallography (Almassy, Janson, Hamlin, Xuong, & Eisenberg (1986) Nature 323, 304-309). The N-terminal amino acid sequence of the Phormidium enzyme shows very high similarity with that of the enzyme from an N2-fixing cyanobacterium, Anabaena 7120; 18 residues are common in 23 residues compared. Strong immunocross-reactions between the antibody against the purified Phormidium glutamine synthetase and other cyanobacterial enzymes except the Anacystis enzyme were observed. The apparent Michaelis constants for NH3, L-glutamate, and ATP were determined to be 0.29, 7.4, and 1.7 mM, respectively. Divalent metal ions such as Mg2+ and Mn2+ activated the enzyme in the biosynthetic reaction, whereas various amino acids and glutamate analogs strongly inhibited the enzyme.

Amino Acid Sequence↗
PubMed1988

Antibody-mediated growth of influenza A NWS virus in macrophagelike cell line P388D1.

We investigated the internalization and growth of influenza A NWS virus in macrophagelike P388D1 cells. Flow cytometric analysis using fluorescein isothiocyanate-labeled virus showed that the attachment of normal rabbit serum-exposed virus (NS-V) to neuraminidase (NA)-treated cells was noticeably limited compared with that to untreated cells. However, rabbit antiserum-exposed virus (AS-V) could attach equally well to both cells. Virus coated with Fab prepared from antiviral immunoglobulin G could not attach. These data suggest that the NWS virus can infect P388D1 cells in one of two ways, via viral or via Fc receptors, depending on the presence of antibodies. The NS-V could grow in the untreated cells, but not in the NA-treated cells. The highest growth of AS-V in the NA-treated cells was observed at an antibody concentration showing 50% plaque reduction titer. Growth was exponentially decreased toward the lower and higher dilutions of antibodies. By using three different immunoglobulin G subclasses of monoclonal antibodies against hemagglutinin, it was demonstrated that both Fc receptors I and II could take part in this phenomenon. The presence of 20 mM NH4Cl inhibited the growth of both AS-V and NS-V, suggesting that the intracellular pathways after internalization via Fc or viral receptors are similar. These data indicate that the concentration of antibodies has a critical role on the antibody-mediated growth of influenza virus in macrophages.

Ammonium Chloride↗
PubMed1988

Induction of intestinal mastocytosis in nude mice by repeated injection of interleukin-3.

The number of mast cells in various tissues of nude mice was examined after daily injection of Interleukin-3 (IL-3), which was purified from the media conditioned by WEHI-3B cell line. Repeated intraperitoneal injection of IL-3 caused a significant increase in the number of mucosal mast cells (MMC) in the epithelium of small intestine more than 30-fold and also to a lesser extent in the villous lamina propria of small intestine and caecum. The number of mast cells in the spleen, approximately 60% of which were formalin-resistant and were assumed as connective tissue type mast cells (CTMC), increased 3-fold by IL-3 treatment. Although statistically not significant, the number of mast cells in the ear skin also slightly increased.

Animals↗
PubMed1988

Incorporation of N4-behenoyl-1-beta-D-arabinofuranosylcytosine into DNA as 1-beta-D-arabinofuranosylcytosine.

BHAC is a newly synthesized lipophilic derivative of ara-C. To clarify its pharmacological mode of action, P388 murine leukemic cells were incubated with two different types of 14C-labeled BHAC, [cytosine-2-14C]BHAC and [acyl-1-14C]BHAC, and DNA was extracted with phenol. The phenol-extracted DNA was then hydrolyzed by nuclease P1 and analyzed with high-performance liquid chromatography (HPLC). The radioactivity of DNA, from the cells incubated with [cytosine-2-14C]BHAC, was detected as ara-CMP. But the radioactivity of DNA, from the cells incubated with [acyl-1-14C]BHAC, was hardly detected. On the other hand, the main radioactivity of the acid soluble fraction was determined as ara-CTP. On the basis of our results, BHAC is not phosphorylated directly to produce N4-behenoyl-ara-CTP, but is mainly converted to ara-C which subsequently produces ara-CTP, the active metabolite of the drug, and which is then incorporated into DNA.

Animals↗
PubMed1988

[Inhibition of pulmonary metastases in mice by beta-cyclodextrin-benzaldehyde].

The effect of beta-cyclodextrin-benzaldehyde (CDBA) on the pulmonary metastasis in C3H/He mice was examined. When mice were treated daily with CDBA, 3 weeks later the number of lung nodules developed after i.v. inoculation of 1 X 10(6) RCT (+) cells was significantly decreased. The mean numbers of the lung nodules were 69.9 and 73.4 in the water-and cyclodextrin (CD)-treated mice, respectively. However, these were 17.8, 9.8 and 2.9 in 0.5, 5 and 25 mg/mouse per day CDBA-treated mice, respectively. And also, daily treatment of CDBA prolonged the survival time of the tumor bearing mice in both experimental and spontaneous metastasis studies. Two or three weeks after subcutaneous inoculation of RCT (+) cells (1 X 10(6) cells) to the foot pad, left hindlimbs were amputated and then mice were daily treated or untreated with CDBA. Five weeks after tumor inoculation, the number of lung nodules was counted. Twenty eight point six and 100% of untreated mice had lung metastases when amputation was carried out 2 (earlier operation group) and 3 (latero peration group) weeks after tumor inoculation. However, in CDBA-treated mice, these values were noticeably decreased, that is, 6.7% and 60% in earlier and later operation groups, respectively. Furthermore, in the later operation group, mean number of the lung nodules in CDBA-treated mice was only 2.7 while this was 12.9 in untreated mice. These data suggest that CDBA improve the survival time of tumor bearing mice through the inhibition of the lung metastasis.

Administration, Oral↗
PubMed1987

Macrophage recognition of the erythrocytes modified by oxidizing agents.

Mouse erythrocytes modified by oxidizing agents (ADP/Fe3+, tert-butyl hydroperoxide and phenylhydrazine) were examined for recognition by autologous macrophages (cell adhesion and phagocytosis). Treatment of erythrocytes with ADP/Fe3+ resulted in lipid oxidation but no significant alterations in physical properties, and the treated cells were adherent to macrophages. When the lipid oxidation of erythrocytes was prevented by alpha-tocopherol, erythrocytes were not susceptible to macrophage adhesion, indicating that free radical reactions involving lipid oxidation are responsible for the formation or exposure of the membrane sites for the macrophage adhesion. Treatment of erythrocytes with tert-butyl hydroperoxide caused lipid oxidation and alterations in physical properties. Deformability and osmotic fragility of the treated cells were markedly low. Not only cell adhesion but subsequent phagocytosis of the treated cells by macrophages were observed. A similar effect was observed on treatment of erythrocytes with phenylhydrazine. The pronounced alterations in physical properties of the erythrocytes treated with tert-butyl hydroperoxide and phenylhydrazine may be responsible for the macrophage phagocytosis.

Adenosine Diphosphate↗