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N Ohno

Publications and source records attributed to N Ohno.

At least 217 records · Page 12Linked to original sources
PubMed1990

Heat induced generation of the mitogenic substance(s) responding to murine splenocytes obtained from sclerotia of Sclerotinia sclerotiorum IFO 9395.

We have demonstrated that hot water extracts of sclerotia of Sclerotinia sclerotiorum IFO 9395 (TSHW) show various immunomodulating activities and mitogenic substance(s) were recovered from the beta-1,3-glucanase resistant-fraction (EDP) (Shinohara et al. Chem. Pharm. Bull., 37, 2174 (1989]. In this paper, we examined whether or not the mitogenic substance(s) were also obtained from the other methods, phosphate buffer extraction. Although the native extracts (3S-M) sterilized with a membrane filter showed a slight mitogenicity to murine splenocytes, 3S-M denatured in boiling water (3S-MB) showed significant activity. Treatment of 3S-M for only 1 min in boiling water or 10 min at 70 degrees C was sufficient to show significant mitogenic activity. After heat treatment of 3S-M in boiling water for 30 s, the main band corresponding to that of 3S-M was not clearly observed. Instead, new bands appeared at the top of the gel in normal-polyacrylamide gel electrophoresis (normal-PAGE), suggesting that many physicochemical changes occurred during the heat treatment. These findings suggest that heat denaturation of the substance(s) from sclerotia was one of the triggering mechanisms expressing mitogenic activity to murine splenocytes.

Animals↗
PubMed1990

Preparation and antitumor activity of hydroxyethylated derivatives of 6-branched (1----3)-beta-D-glucan, SSG, obtained from the culture filtrate of Sclerotinia sclerotiorum IFO 9395.

SSG is an antitumor branched (1----3)-beta-D-glucan obtained from the culture filtrate of Sclerotinia sclerotiorum IFO 9395. Hydroxyethylation of SSG higher than MS 0.45 (MS value represents molar ratio of hydroxyethyl group vs. glucosyl group) by ethyleneoxide in aqueous sodium hydroxide lose the antitumor activity. Degradation of branching point of hydroxyethylated SSG (HE-SSG) by the sequential treatments of periodate oxidation, borohydride reduction, and mild acid hydrolysis of these derivatives regenerated the antitumor activity. These results directly demonstrated that the branching point covered, at least a part of, the dormant active site of SSG.

Animals↗
PubMed1990

Change of biological activities of (1----3)-beta-D-glucan from Grifola frondosa upon molecular weight reduction by heat treatment.

Changes of biological activities manifested by (1----6)-branched (1----3)-beta-D-glucans of various molecular weights obtained by heat treatment of the corresponding intact beta-glucan at 150 degrees C (HD-LE) were examined. The activities assessed in this study were as follows: an antitumor activity, activation of alternative complement pathway, glucose consumption by macrophages, macrophage-mediated lysosomal enzyme activity in culture supernatant and cell lysate, interleukin-1 (IL-1) activity, and adjuvant activity. HD-LE could be classified into three groups: 1) HD-LE 0 h (MW 800000) which activated all of the biological activities tested, 2) HD-LE 0.5 and 3 h (MW 250000 and 21000) which lacked or exhibited low levels of activities such as activation of alternative complement pathway and lysosomal enzyme secretion, 3) HD-LE 6 h (MW 6400) which only activated glucose consumption and synthesis of lysosomal enzyme. These results suggest that an antitumor glucan is not always a multiple enhancer of host defense mechanisms and that a large molecular weight is required to augment multiple immunological activities.

Animals↗
PubMed1990

Macrophage activation in vitro by chemically cross-linked (1----3)-beta-D-glucans.

The chemical cross-linking of soluble (1----3)-beta-D-glucans having molecular weights of 21000 (CL 3 h) and 6400 (CL 6 h), and laminarin (CL LAMI), which showed negligible biological activity, by epichlorohydrin provided rigid particles. These particles showed no gel-to-sol transition upon the addition of sodium hydroxide. We compared the effects of chemical cross-linking on the biological activities of glucans. The alternative complement pathway was not activated by any of the cross-linked glucans. Glucose consumption, lysosomal enzyme release, and interleukin-1 production by mouse resident peritoneal macrophages incubated in vitro were strongly induced by CL 3 h, CL 6 h and CL LAMI. However, cross-linked dextran, Sephadex, did not exhibit any of these biological activities. These results suggested that chemical cross-linking of (1----3)-beta-D-glucans enhances macrophage activities without opsonization by complement components.

Animals↗
PubMed1990

[Free internal mammary artery for coronary bypass].

We studied 12 cases of free internal mammary artery (IMA) grafting. We used IMAs as free grafts mainly because of its shortness (6 cases 50%) and injury during dissection (4 cases 33%) and found the varicose change of saphenous vein in 5 cases (42%). Most of the grafting sites are distal parts of coronary arteries. Proximal anastomosis sites are other vein grafts (3 cases), other IMA grafts (3 cases), vein grafts interposing to the aorta (3 cases), and aorta (1 case). Patency rate of the free IMA grafts 4 weeks after operations was good (82%). Free IMA grafting is safe alternative to in situ IMA grafting when IMA grafts are short or injured and saphenous vein grafting is impossible.

Adult↗
PubMed1990

[A study on interdental spaces of the deciduous dental arch in Indian sample].

The primate spaces are described as a genetic characteristic of all primate dentitions. In homo sapiens, they are limited to the deciduous dentition. We have now investigated the prevalence of primate spaces and interdental spaces in the deciduous dentition by sex and arch in samples from Indian children and the relationship between these spaces and other morphological characteristics of the deciduous dental arches. The samples were taken from 55 school children, 26 males and 29 females aged 5-7 years, belonging to the middle class of socio-economic status and living in New Delhi. The samples were taken during January of 1988. All were free of dental malformations, extractions or caries and a certain children had erupted permanent first molars. The result were as follows: 1. There was a wide variation in the pattern of the interdental spacing. The most common areas of spacing were mesial to the maxillary primary canine (primate spaces) and mesial to the mandibular primary canine (developmental spaces) for all ages. The mandibular primate spaces were considerably less frequent than the maxillary ones. The prevalence of primate spaces and developmental spaces were higher in the maxillary deciduous arch than in the mandibular deciduous arch. 2. Frequent distribution of the occlusal termination type were found to be more variable. The bilateral vertical terminal plane was found in about 50% at ages 5 to 6 of both sexes. The vertical terminal occlusal pattern existed even in the deciduous arches in which the first permanent molars had erupted. 3. The mesiodistal crown diameters of each deciduous tooth were greater in males than in females. The sex differences in mesiodistal crown diameters were significant for mandibular second deciduous molars. The sum of mesiodistal crown diameter in the closed deciduous arches was larger than in the spaced deciduous arches. 4. The dental arch increased slightly in width but decreased a little in length with changes in age during the deciduous dentition period. The deciduous arch diameters in the spaced arches were larger than in the closed arches. Statistically significant differences were found between the spaced arches and the closed arches for the mandibular anterior or posterior arch lengths and the anterior arch width for both arches. Generally, spacing of the deciduous arches was significantly related to the mesiodistal crown diameter, intercanine width and intermolar width, but there was no significant relationship to the eruption of the permanent first molars.

Child↗
PubMed1989

Effects of lipopolysaccharide chemotype structure on binding and inactivation of hen egg lysozyme.

The structural features of lipopolysaccharide [LPS] which influence the binding and inactivation of lysozyme have been examined. Binding of polysaccharide-containing LPS (S-LPS) and Ra-Rc-LPS preparations was independent of temperature between 37-50 degrees C; in contrast, binding of Rd-LPS, Re-LPS and lipid A was temperature-dependent. The binding of lysozyme to Rd-LPS and Re-LPS was increased by treatment with mild alkali, which has little detectable effect on binding of lysozyme to S-LPS and Ra-Rc-LPS preparations. Competitive binding experiments using dansylated lysozyme and/or dansylated polymyxin B indicated independent binding sites on the LPS for lysozyme and polymyxin B. These results indicate significant differences between most LPS preparations and lipid A and glycolipid LPS in their interaction with proteins of mammalian origin.

Animals↗
PubMed1989

Lipopolysaccharide interactions with lysozyme differentially affect lipopolysaccharide immunostimulatory activity.

The effect of complex formation between lysozyme and lipopolysaccharide (LPS) on the immunostimulatory activities of LPS have been investigated in vitro. Three prototype immunostimulatory activities were examined: B-lymphocyte proliferation, B-lymphocyte differentiation and macrophage production of lymphocyte-activating factor activity. Different effects of lysozyme were noted, depending upon the structure of the LPS, even though previous studies have established that all LPS preparations readily bind lysozyme. Both Re-LPS- and lipid-A-dependent immunostimulatory activities were readily inhibited by lysozyme in a dose-dependent fashion. In contrast, S-LPS and Ra-LPS were unaffected in their immunostimulatory activities by lysozyme. These differences were not the result of quantitative differences in LPS binding of lysozyme, or effects of lysozyme on overall binding of LPS to target cells. These data suggest that the factors which dictate the initial interactions between LPS and lymphoreticular cells may not be identical for all LPS preparations and/or purified lipid A.

Adjuvants, Immunologic↗
PubMed1989

Lipopolysaccharide interaction with lysozyme. Binding of lipopolysaccharide to lysozyme and inhibition of lysozyme enzymatic activity.

Experiments have been carried out to characterize the binding of lysozyme (LZM) to bacteriol lipopolysaccharide (LPS). The formation of LPS.LZM complexes can be readily demonstrated using either physical-chemical separation techniques or a radiolabeled photoaffinity LPS probe. The binding affinity of LZM for LPS has been estimated to be approximately 10(8) liters/mol. Binding of LPS results in loss of LZM enzymatic activity by a noncompetitive inhibition, as assessed by either particulate or soluble substrates. This interaction of LPS with LZM is dictated primarily by hydrophobic interactions and appears to be a general property of both constituents. Binding can be demonstrated with LZM of both human and avian sources, as well as with LPS isolated from a variety of Gram-negative organisms. The addition of LPS to biologically relevant fluids containing LZM results in dose-dependent inhibition of LZM enzymatic activity suggesting that such interactions may have relevance in Gram-negative infections. Finally LZM has been shown to reduce the endotoxic activity of LPS as assessed by gelation of Limulus amoebocyte lysates.

Affinity Labels↗
PubMed1989

Immunomodulation by orally administered beta-glucan in mice.

Orally administered SSG, a beta-1,3-glucan obtained from the culture filtrate of the fungus Sclerotinia sclerotiorum IFO 9395, was examined for effects on immune responses in mice. The proliferative responses of spleen cells from SSG-administered mice (40 or 80 mg/kg, daily for 5 or 10 consecutive days) to a T-cell mitogen, concanavalin A (Con A), or a B-cell mitogen, lipopolysaccharide (LPS), were higher than those from normal mice. Oral administration of SSG (80 mg/kg) to mice also enhanced the activities of both natural killer (NK) cells in spleen and the lysosomal enzyme of peritoneal macrophages. Furthermore, significant inhibition of tumor growth was observed in syngeneic tumor systems when SSG was administered directly after tumor implantation. The inhibiting effect required high doses of SSG (over 80 mg/kg). These results demonstrate that SSG can potentiate the immune response of mice following oral administration.

Adjuvants, Immunologic↗
PubMed1989

Modulation of antitumor activity of grifolan by subsequent administration of (1----3)-beta-D-glucanase in vivo.

The initiation process of effector mechanism of the antitumor activity of (1----3)-beta-D-glucans has been examined in detail by applying treatment of mice with (1----3)-beta-D-glucanase, kitalase (KIT) and zymolyase (ZYM), via i.p. route after i.p. administration of (1----3)-beta-D-glucans, grifolan (GRN) and CM-curdlan (CM-CUD). A significant decrease of antitumor activity caused by GRN was observed by treatment with KIT within 48 h, and that caused by GRN administered via i.v. route was also reduced by the i.v. injection of KIT, although it was less effective than i.p. treatment. Pretreatment of mice with thioglycollate reduced the period of time to abrogate antitumor activity by the sequential treatment of KIT. Similar results were also observed on ZYM treatment after i.p. treatment of CM-CUD. These facts suggest that the period of manifestation of the antitumor activity by (1----3)-beta-D-glucans must be longer than a few days.

Adjuvants, Immunologic↗
PubMed1989

Modification of immunostimulating activities of grifolan by the treatment with (1----3)-beta-D-glucanase.

We have developed a method to control the effective time period of (1----3)-beta-D-glucan in vivo by using (1----3)-beta-D-glucanase and found that grifolan LE (GRN), a (1----3)-beta-D-glucan, administered intraperitoneally to the host required more than 2 d to exert antitumor activity. During these two days many immunological changes were induced, such as increasing the number of peritoneal exudated cells (PEC), augmentation of production of interleukin 1 (IL-1), acid phosphatase and phagocytic capacity of adherent cells in PEC. In addition, there was increased carbon clearance activity in vivo, augmentation of responsiveness of splenocytes to mitogens such as concanavalin A and lipopolysaccharide (LPS) and production of ceruloplasmin. When (1----3)-beta-D-glucanase was injected 1 d after GRN administration, IL-1 productivity and responsiveness to LPS were significantly reduced, but lysosomal enzyme activity and phagocytosis of macrophage and production of ceruloplasmin were similar to those not treated with glucanase. These facts indicate that the induction of the activities of the former group requires longer contact of host cells with the glucan, and the latter group requires a shorter period to achieve fully active stages.

Acid Phosphatase↗
PubMed1989

Physiochemical properties and antitumor activities of chemically modified derivatives of antitumor glucan "grifolan LE" from Grifola frondosa.

Antitumor glucan, grifolan LE (GRN LE), from Grifola frondosa was chemically modified to examine the structure-function relationship of the products. Modification by periodate, borohydride and acid hydrolysis of side chains of GRN LE did not alter properties such as helical conformation and antitumor activity of GRN LE. Introduction of carboxylic acid groups into the side chains by oxidation with periodate and with sodium chlorite (GRN LE-PC), and substitution with carboxymethyl (CM) or hydroxyethyl (HE) groups abolished the gel-forming ability of GRN LE. Significant antitumor activity was observed in all of the derivtives having gel-forming ability as well as some derivatives having no such ability. These results suggested that essential factors required for antitumor activity were (1----3)-beta-D-glucosyl linkages and high molecular weight, and that accessory groups could be linked to the main chain without loss of antitumor activity in a higher ratio than that of gel-forming ability.

Animals↗
PubMed1989

Separation of the hot water extracts of sclerotia of Sclerotinia sclerotiorum IFO 9395 into mitogenic and antitumor-active subfractions.

The hot water extract of sclerotia of Sclerotinia sclerotiorum IFO 9395 (TSHW) was divided into representative fractions by ammonium sulfate and ethanol precipitations, and (1----3)-beta-D-glucanase treatment. The ammonium sulfate and ethanol precipitations gave a (1----3)-beta-D-glucan fraction (TSG) and a mannan fraction (TSM). After the degradation of (1----3)-beta-D-glucan in TSHW by (1----3)-beta-D-glucanase treatment, a water-insoluble protein fraction (EDP) and supernatant (EDS) were obtained. Among these fractions, the mitogenic and antitumor activities were mainly observed in EDP and TSG, respectively. On the other hand, the stimulatory effect on the reticuloendothelial system was mainly found in EDP and EDS, and a weak effect was observed in TSG. These findings suggest that the mitogenic and antitumor activities of TSHW were mainly due to the protein and (1----3)-beta-D-glucan, respectively, and that the mitogenic substance (EDP) is tightly bound to (1----3)-beta-D-glucan (TSG) in TSHW, accounting for its solubility in aqueous solution.

Animals↗
PubMed1988

Naturally occurring cytotoxic T lymphocyte precursors with specificity for an Ig idiotype.

The humoral response to the p-azobenzenearsonate hapten in the A/J mouse includes the major cross-reactive idiotype associated with anti-p-azobenzenearsonate (CRIA) found in all immunized mice. Limiting dilution cultures of non-immunized spleen cells of A/J mice with irradiated B hybridoma cells bearing the Ig idiotype, CRIA, in the presence of T cell growth factors developed cytotoxic activity against the CRIA-bearing hybridoma; in some wells this activity was completely abrogated by an anti-idiotype mAb specific for CRIA or by a univalent hapten antigen, tyrosine-p-azobenzenearsonate, indicating the existence of cytotoxic T cell precursors (CTL-P) specific for one or more idiotopes of CRIA in normal spleen cells. The CTL clones lysed targets in a H-2D-restricted manner and were cytotoxic for CRIA-bearing hybridoma lines, but not for CRIA-non-bearing, IgG1k-bearing hybridoma lines. These CTL-P were detected at a high frequency (1/4,500 to 1/10,000) in a spleen cell population of non-immunized, relatively aged A/J mice (16 to 30 wk of age), and at a lower frequency in spleen cells of younger A/J mice (8 wk of age). However, they were not detected in normal spleen cells of B10.A (CRIA-non-producer) mice at any age (less than 1/6 x 10(5)). Normal Ighd-congenic C.AL-20 mice (16 wk of age), that are CRIA producers had as a high frequency of the CTL-P as did A/J mice, whereas normal Ighb-congenic C.B-20 mice (CRIA-non-producers) had none. In the spleen cells of the CRIA-producers, cytotoxicity of the CTL-P developed only in cultures with small numbers of seeding cells. They were completely absent in cultures with greater numbers of cells; this may be due to the presence of suppressor cells of lower frequency but greater potency. In lymph node cells or PBL of relatively aged A/J mice, the CTL-P were also detected, but only in cultures containing higher cell numbers, and at low frequency (between 1/5 x 10(5) to 1/2 x 10(6)). In thymocytes of 8-wk-old A/J mice, they were occasionally detected at very low frequency (less than or equal to 1/1 x 10(6)), but were not present in the bone marrow cells at any age. These results demonstrate the high incidence of the generation of CTL-P specific for an autologous Ag, and indicate that CRIA on B cells may induce CTL specific for CRIA. However, the development of CTL-P may be inhibited by co-existent suppressor cells under normal conditions.

Animals↗
PubMed1988

Fluoride distribution and histological structure of human cementum.

Thirty-one teeth taken post-mortem from 10 subjects aged from 40 to 66 years were studied. A close relationship was found between fluoride (F) distribution and histological structure. Although, as in all mineralized tissues, F concentrations tended to be highest towards the external surface, individual patterns of F distribution also seemed to reflect the histological pattern, especially the distribution of cellular or acellular cementum. In general, F concentrations were high in acellular and low in cellular cementum.

Adult↗
PubMed1988

Distribution of grifolan NMF-5N (I/B), a chemically modified antitumor beta-glucan in mice.

The distribution of a 3H-labeled chemically modified antitumor beta-glucan, grifolan NMF-5N (I/B), in various tissues after an injection into mice was examined in order to obtain information on distribution of the parent antitumor beta-glucan, grifolan NMF-5N. Grifolan NMF-5N was treated with sodium metaperiodate and sodium borotritide to obtain tritium-labeled grifolan NMF-5N [3H-grifolan (I/B)]. When 3H-grifolan (I/B) was administered into normal mice by intraperitoneal (i.p.) or intravenous (i.v.) injection, radioactivity was detected in various mouse tissues. Next, 3H-grifolan (I/B) was injected into tumor-bearing mice 7 d after the tumor inoculation, which is the most effective administration timing for the antitumor effect of grifolan NMF-5N. The results indicated a strong radioactivity in spleens and tumor masses. These results suggested a close relationship between the antitumor activity and the distribution of grifolan NMF-5N in mice.

Animals↗