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Haruki Yamada

Publications and source records attributed to Haruki Yamada.

36 records · Page 2Linked to original sources
PubMed2004

Isolation, partial characterisation and immunomodulating activities of polysaccharides from Vernonia kotschyana Sch. Bip. ex Walp.

The roots from Vernonia kotschyana Sch. Bip. ex Walp. (Baccharoides adoensis var. kotschyana (Sch. Bip. ex Walp.) M.A. Isawumi, G.El-Ghazaly & B. Nordenstam) (Asteraceae) are used in Malian folk medicine for the treatment of gastritis, gastro duodenal ulcers, as an aid to ameliorate digestion and as a wound healing remedy. Since a common feature among these conditions is related to immune responses, immunomodulating activities of fractions isolated from both the 50 degrees C and the 100 degrees C water extracts from Vernonia kotschyana were investigated in this study. The active principles were identified as acidic polysaccharide fractions, containing pectic arabinogalactan type II structures, which showed both complement fixing ability and T-cell independent induction of B-cell proliferation in vitro. Some activity was also observed on macrophages. The present study may provide additional support for the popular use of this plant to improve intestinal health.

Animals↗
PubMed2004

In vitro antimalarial activity of biflavonoids from Wikstroemia indica.

In our investigation of in vitro antimalarial screening of medicinal herbal extracts, the n-BuOH extract from the root of Wikstroemia indica showed a potent inhibitory effect. Fractionation of the active extract led to the isolation of two biflavonoids, sikokianin B ( 1) and sikokianin C ( 2) with IC (50) values 0.54 microg/mL and 0.56 microg/mL, respectively, against the chloroquine-resistant strain of Plasmodium falciparum. This is the first report of the biological activity of 1 and 2. As the structure of l has remained unsettled, we confirmed the conformation by (1)H- and (13)C-NMR.

Animals↗
PubMed2004

A novel in vitro infection model of Helicobacter pylori using mucin-producing murine gastric surface mucous cells.

BACKGROUND: Helicobacter pylori is found within the gastric surface mucous gel layer and in the epithelial surface. Gastric cancer cells have been used in experimental H. pylori infection in vitro, although cancer cells have some abnormalities in cellular properties. The aim of this study was to develop an in vitro H. pylori infection model using normal gastric surface cells that produce gastric mucin. MATERIALS AND METHODS: Normal murine gastric surface mucous cells (GSM06) were cultured by the liquid interface method using a serum-free medium and a collagen gel containing a fibroblast cell line (L929) and infected with H. pylori. Infection by H. pylori was assessed by enumerating the colony-forming units (CFU) of H. pylori adhered to GSM06 cells and by transmission electron microscopy. The production of mucin was determined by a lectin binding assay, sugar analysis, and MUC5AC gene expression. RESULTS: GSM06 cells cultured under these conditions produced mucin containing N-acetylgalactosamine and MUC5AC as the core protein. Significantly higher numbers of H. pylori adhered to GSM06 cells under mucin-producing conditions than under nonproducing conditions. Microscopic observation showed a filamentous structure resembling a type IV secretion system apparatus formed between the surface of GSM06 cells and H. pylori. CONCLUSIONS: This study demonstrates a novel in vitro H. pylori infection model using mucin-producing murine GSM06 cells for early stages of infection.

Acetylgalactosamine↗
PubMed2004

Phycocyanin enhances secretary IgA antibody response and suppresses allergic IgE antibody response in mice immunized with antigen-entrapped biodegradable microparticles.

In the present study, we have investigated the effects of phycocyanin, a biliprotein of Spirulina platensis, on mucosal and systemic immune responses and allergic inflammation in C3H/HeN and BALB/cA mice. To induce the antigen-specific antibodies in the peripheral lymphoid tissues such as Peyer's patches and mesenteric lymph nodes, biodegradable ovalbumin-entrapped poly (DL-lactide-co-glycolide) particles were used as an antigen. Two weeks after the onset of phycocyanin ingestion, mice were immunized with an aqueous ovalbumin (OVA) solution. Starting at one week after the primary immunization, the mice were subjected to oral immunization with the biodegradable OVA microparticles twice a week. IgA, IgE and IgG1 antibodies were determined by ELISA. The OVA microparticles of 4-microm diameter successfully induced antigen-specific antibodies. In the mice that received phycocyanin treatment for 6 wk, a marked increase in the antigen-specific, as well as the total, IgA antibody level was observed in the Peyer's patches, mesenteric lymph nodes and intestinal mucosa as well as in the spleen cells. Both antigen-specific IgG1 and IgE antibody levels in the serum were suppressed by ingestion of phycocyanin for 8 wk. However, inflammation of the small intestine, monitored as vascular permeability by the Evans blue-leaking method was reduced by phycocyanin at 6 wk, which preceded the suppression of antigen-specific IgG1 and IgE antibody production by 2 wk. These results suggest that phycocyanin enhances biological defense activity against infectious diseases through sustaining functions of the mucosal immune system and reduces allergic inflammation by the suppression of antigen-specific IgE antibody.

Animals↗
PubMed2003

Overexpression of P104L mutant caveolin-3 in mice develops hypertrophic cardiomyopathy with enhanced contractility in association with increased endothelial nitric oxide synthase activity.

The effect of endogenous nitric oxide synthase (NOS) on cardiac contractility and architecture has been a matter of debate. A role for NOS in cardiac hypertrophy has recently been demonstrated by studies which have shown hypertrophic cardiomyopathy (HCM) with altered contractility in constitutive NOS (cNOS) knockout mice. Caveolin-3, a strong inhibitor of all NOS isoforms, is expressed in sarcolemmal caveolae microdomains and binds to cNOS in vivo: endothelial nitric oxide synthase (eNOS) in cardiac myocytes and neuronal nitric oxide synthase (nNOS) in skeletal myocytes. The current study characterized the biochemical and cardiac parameters of P104L mutant caveolin-3 transgenic mice, a model of an autosomal dominant limb-girdle muscular dystrophy (LGMD1C). Transgenic mouse hearts demonstrated HCM, enhanced basal contractility, decreased left ventricular end diastolic diameter, and loss and cytoplasmic mislocalization of caveolin-3 protein. Surprisingly, cardiac muscle showed activation of eNOS catalytic activity without increased expression of all NOS isoforms. These data suggest that a moderate increase in eNOS activity associated with loss of caveolin-3 results in HCM.

Animals↗
PubMed2003

Induction of cell cycle regulatory proteins by murine B cell proliferating pectic polysaccharide from the roots of Bupleurum falcatum L.

Bupleuran 2IIc, a pectic polysaccharide isolated from the roots of Bupleurum falcatum L., was characterized as a T-cell-independent B cell mitogen, that activates, proliferates and differentiates B cells in vivo and in vitro (Immunology 97 (1999) 540). Studies were focused on elucidating the mechanism by which bupleuran 2IIc causes proliferation of B cells and expression of cell cycle regulatory proteins. B cells showed slower rates of entry into the S and G2/M phases of the cell cycle when stimulated with bupleuran 2IIc versus anti-IgM. However, the Stimulation Index continued up to two times longer with bupleuran 2IIc over anti-IgM. Although both bupleuran 2IIc and anti-IgM induced similar expressions of cell cycle regulatory proteins, cyclins D2, A, and B1, in B cells, those cells stimulated with bupleuran 2IIc appeared to sustain expressions of these protein for longer periods of time. Stimulation of B cells with bupleuran 2IIc induced phosphorylation of retinoblastoma protein, pRB, an important gene product regulating the restriction point, R, which is responsible for the transition from the G0/G1 to the S phases of the cell cycle. The results of this study demonstrate that both bupleuran 2IIc and anti-IgM interact with B cells, thus, leading to expressions of cell cycle regulatory proteins. However, the respective modes of binding and proximity of interactions with the B cell membrane may differ.

Animals↗
PubMed2003

Total synthesis and adjuvant activity of all stereoisomers of pinellic acid.

Pinellic acid is a novel and potentially useful oral adjuvant when used in conjunction with intranasal inoculation of influenza HA vaccines. All stereoisomers of pinellic acid have been synthesized via regioselective asymmetric dihydroxylation, regioselective inversion, and stereoselective reduction, and their adjuvant activities were characterized. Among this series of isomers, 9S, 12S, 13S compound has the most potent adjuvant activity. Structure-activity relationships are discussed.

Adjuvants, Immunologic↗
PubMed2003

Antimetastatic and immunomodulating properties of a new herbal prescription, Bojung-bangam-tang.

We investigated the antimetastatic effect of Bojung-bangam-tang, a new herbal prescription, on liver metastasis by the inoculation of colon 26-L5 carcinoma cells into the portal vein. Oral administration of Bojung-bangam-tang for 15 days from day 7 before tumor inoculation significantly inhibited liver metastasis in a dose-dependent manner. Bojung-bangam-tang enhanced the mitogenic activity of BALB/c whole splenocytes induced by various mitogenic stimuli. Oral administration of Bojung-bangam-tang, by itself, could not induce the production of interleukin (IL)-12 or IFN-gamma by macrophages, but enhanced the potential of macrophages to produce cytokines in response to lipopolysaccharide (LPS). Experiments using macrophage- or natural killer (NK) cell-deficient mice revealed that the antimetastatic effect of Bojung-bangam-tang is mediated by macrophages rather than NK cells. Bojung-bangam-tang caused a marked increase of production of Th1 cytokine (IFN-gamma) and decrease of production of Th2 cytokine (IL-4) by splenocytes stimulated with concanavalin A (Con A). These results indicated that oral administration of Bojung-bangam-tang inhibited the liver metastasis of colon 26-L5 cells through a mechanism leading to a Th1 dominant immune state and activation of macrophages. Thus, Bojung-bangam-tang may be useful for the prevention of cancer metastasis.

Adjuvants, Immunologic↗
PubMed2003

Thrombopoietin-producing hepatocellular carcinoma.

A 66-year-old man with hepatocellular carcinoma (HCC) showed marked thrombocytosis (110.7 x 10(4)/microl). Bone marrow (BM) aspirates demonstrated an increase of mature megakaryocytes (MgK). The serum thrombopoietin (TPO) level was increased to about 100-fold that of the normal level in the terminal stage. However, the platelet count gradually decreased to 13.5 x 10(4)/microl. The autopsy specimen revealed normoplastic BM with decreased MgK, mainly consisting of the immature type, and it was negative for tumor cells. Liver specimen showed markedly fatty metamorphosis. Immunohistochemical staining of TPO demonstrated that hepatocytes were weakly stained and HCC cells strongly stained, suggesting TPO-producing HCC.

Aged↗
PubMed2002

Acute onset of nephrotic syndrome during interferon-alpha retreatment for chronic active hepatitis C.

A 57-year-old woman was scheduled to receive recombinant interferon-alpha retreatment for chronic active hepatitis C. During the course of therapy, the patient showed rapid onset of oliguria, dizziness, edema, and a pre-shock state. She was subsequently admitted to hospital and was diagnosed as having nephrotic syndrome. After admission, albumin-dominant proteinuria persisted despite the discontinuation of interferon therapy. Light microscopy of a renal needle biopsy specimen showed interstitial lymphoid cell infiltration, but no marked changes of the glomeruli and no staining for immunoglobulin or complement. Electron microscopy showed diffuse effacement of the glomerular epithelial foot processes, leading to a diagnosis of minimal change nephrotic syndrome with interstitial nephritis. Proteinuria resolved after the initiation of oral prednisolone therapy (1 mg/kg per day). The number of patients with chronic hepatitis C requiring interferon retreatment is increasing rapidly. We herein report this rare case of acute onset of nephrotic syndrome during interferon-alpha retreatment.

Acute Disease↗
PubMed2002

Galactose-containing polysaccharides from Dictyostelium mucoroides as possible acceptor molecules for cell-type specific galactosyl transferase.

Dictyostelium discoideum has polysaccharides that accept galactose residues by the action of cell-type-specific galactosyl transferase. This paper describes partial purification of the major galactose-accepting polysaccharide that was isolated from the related strain, Dictyostelium mucoroides and proposes its plausible carbohydrate sequences. The most potent acceptor activity was observed in the neutral and Ricinus communis agglutinin (RCA-60) bound galactosaminoglycan, consisting of galactose (Gal) and galactosamine (GalN). However, the acceptor polysaccharides are highly heterogeneous in the reactivity with RCA-120 and in molecular mass. The peak fraction was analyzed by (1)H- and (13)C-NMR studies, methylation analysis, beta-D-galactosidase digestion, controlled Smith degradation and reducing terminal analysis. Based on these results, we tentatively propose the following novel type of the common carbohydrate sequences as the acceptor polysaccharides. [abstract - see text].

Animals↗
PubMed2002

Pinellic acid from the tuber of Pinellia ternata Breitenbach as an effective oral adjuvant for nasal influenza vaccine.

This study describes the isolation, purification, characterization, and adjuvant activity of an orally active adjuvant substance from the tuber of Pinellia ternata, as an active herbal component of the traditional Japanese herbal (Kampo) medicine, Sho-seiryu-to (SST, Chinese name: Xiao-Qing-Long-Tang), which has been reported to show oral adjuvant activity for nasally administered influenza HA vaccine [Int. J. Immunopharmacol. 16 (1994) 605]. The active compound was identified as 9S, 12S, 13S-trihydroxy-10E-octadecenoic acid using infrared spectra, proton magnetic resonance, mass spectrometry, and circular dichroism, and named pinellic acid. Oral administration of pinellic acid (1 microg) to BALB/c mice given primary and secondary intranasal inoculations of influenza HA vaccine (1 microg) enhanced antiviral IgA antibody (Ab) titers 5.2- and 2.5-fold in nasal and bronchoalveolar washes, respectively, and antiviral IgG Ab titers 3-fold in bronchoalveolar wash and serum. Intranasal administration of pinellic acid (1 microg) with influenza HA vaccine (1 microg) slightly enhanced antiviral IgG Ab titers in bronchoalveolar wash and serum but not antiviral IgA Ab titers in nasal and bronchoalveolar washes. Pinellic acid showed no hemolytic activity. The results of this study suggest that pinellic acid may provide a safe and potent oral adjuvant for nasal influenza HA vaccine.

Adjuvants, Immunologic↗
PubMed2002

Treatment of Shwachman syndrome by Japanese herbal medicine (Juzen-taiho-to): stimulatory effects of its fatty acids on hemopoiesis in patients.

Juzen-taiho-to (a Japanese herbal medicine) has been traditionally administered to patients with anemia, neutropenia, or wasting syndrome. We previously attempted to isolate and purify the hemopoiesis-stimulatory components in Juzen-taiho-to extracts using an in vitro hemopoietic stem cell (HSC) assay method in which mouse HSCs can proliferate on a stromal cell line (MS-5). We have found that fatty acids (particularly oleic acid and linolenic acid) actively promote the proliferation of HSCs, and that the effect is mediated by stromal cells, rather than by any direct action on the HSCs. In the present study, we show, using human normal bone marrow cells (BMCs) and umbilical cord blood cells, that similar stimulatory effects are due to the presence of oleic acid and linolenic acid, which stimulate the proliferation of HSCs in stroma-based culture systems. Furthermore, a marked stimulatory effect was noted on BMCs from patients with Shwachman syndrome, which shows pancreatic and bone marrow dysfunctions. We also show the data on hemopoietic recovery after the administration of Juzen-taiho-to to a patient with Shwachman syndrome. These findings suggest that decreased fatty acid levels in the blood, caused by exocrine pancreatic insufficiency, induce bone marrow dysfunction in Shwachman syndrome.

Bone Marrow Diseases↗