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Biomedical subjects

Y Sano

Publications and source records attributed to Y Sano.

At least 145 records · Page 8Linked to original sources
PubMed1997

Cloning of the cDNA for a mouse homologue of human PHBP: a novel hyaluronan-binding protein.

The cDNA which encodes the mouse counterpart of human plasma hyaluronan-binding protein (PHBP) was isolated and characterized. The clone contained an insert of 2153 bp, which contained the 1674-bp open reading frame coding for a polypeptide of 558 amino acid residues. The amino acid sequence of mouse PHBP predicted from the nucleotide sequence of cDNA shows reasonable homology to that of human PHBP. Like human PHBP, the amino acid sequence predicted from the nucleotide sequence of mouse PHBP cDNA exhibited significant homology to that of human hepatocyte growth factor activator (HGFA).

Amino Acid Sequence↗
PubMed1997

[Difference of blood cell counts with reference blood cell counters in different makers: Part II].

This is the second report of evaluation on the difference of blood cell counting among different automated blood cell counters in Japan. We tested reference blood cell counters of 6 different companies: Coulter, Sysmex, Bayer-Sankyo, Nihon Kohden, Horiba and Dainabot. Forty ml of whole blood were taken from 3 healthy persons and EDTA-2K anticoagulated blood samples (Sample 1, 2 and 3) were sent to each company to determine blood cell counts with a reference automated counter. As a result, the following items showed more than 10% difference among makers: RBC between Dainabot and Horiba in Sample 3, hematocrit values between Coulter and Dainabot in Sample 2, WBC between Nihon Kohden and each of three makers (Sysmex, Horiba and Dainabot) in all 3 samples and that between Bayer-Sankyo and each of two makers (Sysmex and Horiba) in Sample 3 and platelet count between Dainabot and each of 3 makers (Bayer-Sankyo, Nihon Kohden and Horiba) in all 3 samples. The following items showed difference between 5 and 10%: MCV between Coulter and each of two makers (Bayer-Sankyo and Horiba), WBC between each of two makers (Coulter and Nihon Kohden) and each of other 4 makers, and platelet count between each of two makers (Nihon Kohden and Horiba) and each of 3 makers (Coulter, Sysmex and Bayer-Sankyo). Recently Japanese Committee for Clinical Laboratory Standards proposed minimum clinical allowance of blood cell count as follows: hemoglobin 3%, RBC 4%, MCV 4%, WBC 7% and platelet count 10%. It is suggested that all of the items showing the difference more than above allowance among makers should be improved for clinical use to have good external quality control in blood cell counting by automated instruments.

Blood Cell Count↗
PubMed1997

Murine orthotopic corneal transplantation in high-risk eyes. Rejection is dictated primarily by weak rather than strong alloantigens.

PURPOSE: Using a model of orthotopic corneal transplantation in which allografts were placed in normal eyes of mice, the authors previously reported that grafts bearing minor H antigens alone are more likely to be rejected (approximately 50%) than are grafts displaying only major histocompatibility (MHC) alloantigens (20%). These studies have been extended to include corneal grafts placed in neovascularized high-risk eyes of recipient mice. METHODS: Neovascularization was induced by placing sutures in the central cornea of one eye of recipient mice. Two weeks later, MHC class I only, class II only, minor H only, or MHC+minor H disparate corneas were grafted into these sutured eyes, and their rejection rates were examined. RESULTS: Although MHC+minor H disparate corneal allografts were rejected uniformly in neovascularized graft beds in 12 (100%) of 12, MHC class I only disparate grafts were rejected in 8 (66.7%) of 12 and MHC class II only disparate corneal allografts were rejected in 7 (58.3%) of 12. Surprisingly, the rejection rate of minor H only disparate corneal allografts was 10 (90.9%) of 11. CONCLUSIONS: These findings indicate that for orthotopic corneal allografts placed in high-risk graft beds, minor H antigens offer a more formidable barrier to graft acceptance than do MHC-encoded antigens. The authors speculate that this unexpected outcome may reflect a reduced level of MHC expression on corneal tissue. Moreover, because the cornea as a graft lacks bone marrow-derived dendritic cells, allorecognition by recipient T cells must occur by way of the indirect pathway of alloantigen processing, and in this situation, minor H antigens may compete favorably with MHC antigens for presentation by recipient antigen-presenting cells that infiltrate the graft.

Animals↗
PubMed1997

Helicobacter pylori infection in early gastric adenocarcinoma: relationship between histologic subtypes and ulcer-formation.

Early stage of gastric cancers were divided into two subtypes; differentiated and undifferentiated adenocarcinomas, histologically. We examined the involvement of Helicobacter pylori (Hp) infection in the development and progression of cancer, and presence or absence of peptic ulcer (UL+/UL-). From the results, these findings obtained as follows; 1) Hp positive rate of UL+ group was significantly higher than that of UL-group. 2) Neither of gross features nor depth of the tumor did not correlate with Hp positive rates. 3) Hp positive rate of undifferentiated type carcinoma was significantly higher than that of differentiated type, contrarily to our expectation. These findings suggested that Hp infection might relate with ulcer formation in the cancerous lesion. The hypothesis which is "gastritis-intestinal metaplasia-differentiated type carcinoma sequence" was not supported by present study. Hence, Hp infection was suggested as an important factor of the gastric cancer development and progression, not only in differentiated type but also in undifferentiated type.

Adenocarcinoma↗
PubMed1996

Development of protamine-bonded phase for separation of saccharides in liquid chromatography.

A protamine-bonded polymer gel was synthesized by passing this protein through an activated carbamate polyamine polymer gel layer. This new packing material was suitable for versatile separation of monosaccharides, oligosaccharides, sugar alcohols and uronic acids in liquid chromatography. The column packed with this gel could be operated at room temperature and gave excellent recovery for the reducing monosaccharides such as 2-deoxyribose, 2-deoxyglucose, ribose and mannose for which the conventional alkylamine-bonded phase column gave poor recovery. This column was used for the analysis of saccharides in urine using a post-column reaction detection system.

Amino Acid Sequence↗
PubMed1996

Bias in the gamma delta T cell response to Listeria monocytogenes. V delta 6.3+ cells are a major component of the gamma delta T cell response to Listeria monocytogenes.

Despite extensive research, the role that gamma delta T cells play in the immune response to infectious disease has yet to be established. Here we report the generation of a mAb specific for the V delta 6.3 TCR and investigate the gamma delta+ and V delta 6.3+ T cell responses to the intracellular bacterium Listeria monocytogenes in BALB/c mice. By infecting animals with various doses of Listeria and analyzing the components of the cellular immune response at the two primary sites of infection, the liver and spleen, we have shown that the kinetics, composition, and magnitude of the gamma delta and V delta 6.3 T cell responses are dependent upon the injected dose of bacteria and the organ in which the infection is established. At low doses of infection, the gamma delta T cell response occurs late in the disease course, while at high doses, the response is earlier and of greater magnitude, particularly in the liver. At all infectious doses and in both tissues, the V delta 6.3+ population predominates and together with V delta 4+ cells composes the bulk of the gamma delta T cell response. Changes in the morphology of gamma delta+ and V delta 6.3+ cells at the site of infection are consistent with cellular activation and suggest that these cells are active participants in the Listeria-induced immune response. The results of our study suggest that many features of the gamma delta T cell response to Listeria are dose and tissue related.

Animals↗
PubMed1996

Fine Needle Aspiration Cytology of Argyrophilic Mucinous Carcinoma of the Male Breast.

The results of fine needle aspiration (FNA) cytology of case of argyrophilic mucinous carcinoma of the male breast is presented. The smear obtained from the tumor showed many loose clusters of atypical cells with abundant granular cytoplasm in the mucous background. Most tumor cells showed a plasmacytoid appearance with eccentric nuclei. Numerous fine granules and a few large droplets were found in the cytoplasm. The characteristic light microscopic feature of this lesion was organoid nest formation of tumor cells in mucous lakes. The Grimelius method revealed numerous argyrophilic granules in the cytoplasm and immunohistochemistry showed a positive reaction for chromogranin A. Thus, this tumor revealed the cytomorphologic characteristics of mucinous as well as argyrophilic carcinoma, simultaneously.

Journal Article↗
PubMed1996

The ankyrin repeats but not the PEST-like sequences are required for signal-dependent degradation of IkappaBalpha.

The nuclear activity of Rel/NFkappaB transcription factors is tightly regulated from the cytoplasmic compartment by an inhibitory subunit called IkappaBalpha. IkappaBalpha is rapidly phosphorylated and degraded in response to the stimulation through tumor necrosis factor alpha (TNFalpha) receptor, interleukin-1 receptor or CD40. To explore the molecular mechanisms of signal-induced depletion of IkappaBalpha, we have delineated the domain in IkappaBalpha that is required for TNFalpha-induced phosphorylation and rapid degradation of IkappaBalpha. In contrast to the previous reports, the PEST-like sequences, which are present in the carboxyl-terminal region of IkappaBalpha, are demonstrated here to be dispensable for TNFalpha-induced degradation but could be required for signal-independent degradation, as in the case of Cactus, Drosophila homologue of IkappaB. Furthermore, the ankyrin repeats, which are essential for forming a complex with Rel and RelA, are required for TNFalpha-induced degradation suggesting that the putative IkappaB protease could interact with IkappaBalpha in complex with RelA or could recognize the structure of ankyrin repeats. Our data also indicate that neither the ankyrin repeats nor the PEST-like sequences, are essential for TNFalpha-induced phosphorylation.

Amino Acid Sequence↗
PubMed1996

Changes in descemet membrane and endothelium after corneal epithelial abrasion alone and with photorefractive keratectomy in rabbits.

OBJECTIVES: To investigate the effects of epithelial abrasion on the corneal endothelium and Descemet membrane in rabbits and to compare the changes with those after excimer laser photoablation of the cornea. METHODS: Central epithelial abrasions, 6 mm in diameter, were created by mechanical removal of the cells, and the specimens were examined from 24 hours up to 30 days by transmission electron microscopy. Corneas that were photoablated by an excimer laser and nontreated normal corneas were investigated as controls. RESULTS: Corneas denuded of epithelium showed massive enlargement of the mitochondria in the endothelium and exhibited a layer of electron-dense fibrillogranular material that had migrated forward through the Descemet membrane. These alterations were similar to the changes observed after photoablation of the cornea by an excimer laser. CONCLUSION: It was postulated that the extrusion of electron-dense material in the Descemet membrane observed after excimer laser ablation might have occurred primarily not as a result of shock waves, but from destruction of the epithelial integrity.

Animals↗
PubMed1996

Effect of a single injection of high-dose FK506 on lung transplantation in rats.

Orthotopic left lung grafts from Brown Norway (BN) donors were transplanted to Lewis (LEW) rat recipients which had been treated with a single dose of FK506 10mg/kg body weight intramuscularly on postoperative day 3. Although the lungs were rejected with a median survival time of 7 days, with a range of 6-8 days in the untreated controls, maximum survival was prolonged to 60 days. The major adverse effects of this therapy were reduction of feeding, loss of body weight, and diarrhea. One of the 7 rats died on the 21st postoperative day due to anorexia. The effects of this therapy were investigated by histopathological examination and flow cytometric analysis using monoclonal antibodies against rat lymphocytes: OX-39 (anti-interleukin 2 receptor (IL-2R)) and OX-6 (anti-class II MHC). Histopathologically, the lung allografts showed mild perivascular and peribronchiolar cuffs of mononuclear cells, while marked reduction of the thymic medulla with FK506 treatment was also observed. Flow cytometric analysis of the transplanted lung showed no significant changes. Regarding the thymus, the percentages of positive cells labeled with OX-39 and OX-6 were significantly suppressed after this treatment. In the spleen, the number of OX-6-positive cells significantly decreased. The results using this therapy thus suggest that the suppression of IL-2R and MHC class II expression was systemically maintained for a long time.

Animals↗
PubMed1996

Role of donor-specific cytotoxic T cells in rejection of corneal allografts in normal and high-risk eyes.

Clinical ophthalmologists are highly successful in grafting allogeneic corneas onto healthy eye graft beds--only a small percentage are rejected. By contrast, a high percentage of allografts are rejected when grafted into vascularized or '"high-risk' recipient eyes. The following experiments test the hypothesis that donor-specific cytotoxic T cells mediate graft rejection in high-risk, but not normal, eyes. MHC plus minor histoincompatible C57BL/6 corneas were grafted orthotopically onto BALB/c mice. Healthy recipient eyes were trephined and served as normal graft beds; corneal vascularization was induced by penetrating sutures and these eyes served as 'high-risk' graft beds. Cytotoxic T cells were assayed at 2 and 8 weeks postgrafting using either draining cervical lymph nodes or spleen cells restimulated for 3 days with irradiated allogeneic splenic stimulator cells. As a positive control, donor-specific cytotoxic T cells were induced in mice immunized by subcutaneous injection of allogeneic spleen cells. A low percentage (only 50%) of corneal allografts were rejected when placed orthotopically onto normal healthy eyes. Donor-specific cytotoxic cells were not detected in the draining lymph nodes or spleens of mice that either accepted, or rejected their corneal graft. The failure to detect cytotoxic T cells was not due to anergy or the deletion of allospecific precursors of cytotoxic T cells. By contrast, 97% of corneal allografts were rejected from high-risk recipient eyes (no immune privilege). Donor-specific cytotoxic T cells were routinely detected in the draining lymph nodes of these mice and their appearance coincided with graft rejection. We conclude that allografts placed onto normal healthy eyes fail to induce donor-specific cytotoxic T cells. In the absence of specific cytotoxic T cells, other alloimmune effectors are less successful at mediating rejection. By contrast, allografts placed onto high-risk eyes induce donor-specific cytotoxic T cells, and all grafts are universally rejected. These results imply that immune privilege can protect corneal allografts from most effector mechanisms, except cytotoxic T cells.

Animals↗
PubMed1996

Minor H, rather than MHC, alloantigens offer the greater barrier to successful orthotopic corneal transplantation in mice.

Irrespective of HLA matching, a far higher proportion of human corneal allografts placed orthotopically in avascular corneal graft beds are accepted indefinitely, compared to other types of solid tissue allografts. However, many more corneal grafts are rejected if they are transplanted onto neovascularized recipient eyes. Using a murine model of orthotopic corneal transplantation in which grafts were placed in normal eyes, we have reported previously that grafts bearing minor H antigens alone are more likely to be rejected (approximately 50%) than are grafts displaying only MHC alloantigens (< 20%). Moreover, recipients of MHC plus minor H incompatible corneal grafts developed delayed hypersensitivity (DH) directed solely at minor H antigens. These studies have now been extended to include corneal grafts placed in neovascularized recipient eyes. Neovascularization was induced by placing sutures in the central cornea of one eye of BALB/c mice. Two weeks later corneas from C57BL/10 donors were grafted into these eyes. Rejection reactions were first apparent within 7 days and all grafts were destroyed by 14 days. Donor-specific DH responses were examined by injecting irradiated donor antigen-bearing spleen cells into the ear pinna. To distinguish DH directed at MHC versus minor antigens, some graft recipients were ear-challenged with BALB.B cells (donor MHC only), while other received B10.D2 cells (donor minor H only). Intense ear-swelling responses were evoked by B10.D2 cells, but not by BALB.B cells. These findings indicate that, for orthotopic corneal allografts, minor H antigens offer a more formidable barrier to graft acceptance than do MHC-encoded antigens. We speculate that this unexpected outcome may reflect a reduced level of MHC expression on corneal tissue. Moreover since the cornea lacks bone marrow derived dendritic cells, allorecognition by recipient T cells must occur via the indirect pathway, and in this situation minor H antigens may compete favorably with MHC antigens for processing and presentation by recipient antigen-presenting cells.

Animals↗
PubMed1996

Primary structure of the pig homologue of human IHRP: inter-alpha-trypsin inhibitor family heavy chain-related protein.

The pig counterpart of human IHRP has been isolated from pig serum, and cDNA clones encoding this counterpart were isolated and characterized. The amino acid sequence of pig IHRP predicted from the nucleotide sequence of its cDNA shows reasonable homology to that of human IHRP. The nucleotide sequence of pig IHRP cDNA is identical to that of the mRNA partially determined to be the heavy chain of pig ITI [Buchman et al. (1990) Surgery 108, 560-566]; it is one of the major mRNAs induced in pig liver on cardiogenic shock. Thus we concluded that the reported mRNA should code for IHRP and not for the heavy chain of ITI. The pig IHRP also seems to be identical to pig-MAP, which was recently reported to be a major acute phase serum protein in pig [Gonzalez-Roman et al. (1995) FEBS Lett. 371, 227-230]. The results suggest that IHRP might be involved in acute phase reactions.

Acute-Phase Proteins↗
PubMed1996

Purification and characterization of a novel hyaluronan-binding protein (PHBP) from human plasma: it has three EGF, a kringle and a serine protease domain, similar to hepatocyte growth factor activator.

A novel hyaluronan-binding protein (PHBP) was purified from human plasma by affinity chromatography on hyaluronan-conjugated Sepharose. The contaminating IgM and albumin in the partially purified preparation were removed with anti-IgG antibody-conjugated Sepharose and anti-albumin antibody-conjugated Sepharose, respectively, and no other contaminant was observed. Finally, 800 micrograms of PHBP was isolated from 500 ml of human plasma. PHBP gave a single 70-kDa band on SDS-PAGE under non-reducing conditions, and 50-kDa and 17-kDa bands under reducing conditions. Thus, PHBP was a heterodimer composed of 50-kDa and 17-kDa subunits, bridged by a disulfide linkage. Both subunits had novel N-terminal amino acid sequences, indicating that PHBP was a novel hyaluronan-binding protein in human plasma. The amino acid sequence deduced from the nucleotide sequence of the cloned PHBP cDNA exhibited significant homology to that of hepatocyte growth factor activator (HGFA). The results of Northern blot analysis indicated that liver, kidney, and pancreas expressed PHBP mRNA. The predicted structure of PHBP showed three epidermal growth factor (EGF) domains, a kringle domain and a serine protease domain, from its N-terminus, although HGFA has a fibronectin type II domain, an EGF domain, a fibronectin type I domain, an EGF domain, a kringle domain, and a serine protease domain, from its N-terminus.

Amino Acid Sequence↗
PubMed1996

The O polysaccharide chain of the lipopolysaccharide from Vibrio cholerae O76 is a homopolymer of N-[(S)-(+)-2-hydroxypropionyl]-alpha-L-perosamine.

Chemical and serological studies of LPS from Vibrio cholerae O76 (O76) were performed. The LPS of O76 contained D-glucose, D-galactose, L-glycero-D-manno-heptose, D-fructose, D-glucosamine, D-quinovosamine (2-amino-2,6-dideoxy-D-glucose) and L-perosamine (4-amino-4,6-dideoxy-L-mannopyranose). The sugar composition of the LPS from O76 was quite similar to that of LPS from V. cholerae O1 with the exception of the presence of a small amount of D-galactose in the LPS of O76. However, perosamine, a major sugar component of the LPS from O76, was in the L configuration in contrast to the D configuration of the perosamine in the LPS of V. cholerae O1. The L-perosamine was N-acylated with an (S)-(+)-2-hydroxypropionyl group in the LPS from O76. Structural analysis by NMR spectroscopy, as well as GC/MS, revealed that the O polysaccharide chain of the LPS from O76 was an alpha(1-->2)-linked homopolymer of N-[(S)-(+)-2-hydroxypropionyl]-L-perosamine. The serological cross-reactivity between the LPS of O76 and the LPS from other strains, such as V. cholerae O1 (Ogawa and Inaba O forms), Vibrio bio-serogroup 1875 (Original and Variant strains), V. cholerae O140 (Hakata) and Yersinia enterocolitica O9, was examined in passive haemolysis tests with sheep red blood cells that had been sensitized with LPS and antisera raised against whole cells of these bacteria. The latter six strains have in common the O antigen that includes Inaba antigen factor C, in addition to their own O-antigenic factors. Thus, they crossreact serologically. The O polysaccharide chains of the LPS of these six trains are known to consist exclusively of alpha(1-->2)-linked D-perosamine homopolymers and differences are found only among the N-acyl substituents. In passive haemolysis tests, the LPS of O76 did not cross-react serologically with any of the other LPS examined. Thus, the results obtained in this study support the hypothesis that Inaba antigen factor C, associated with the O antigens of these six strains, which include V. cholerae O1, is related substantially and exclusively to their alpha(1-->2)-linked homopolymers of N-acylated D-perosamine, and not to such homopolymers of N-acylated L-perosamine.

Acetylation↗
PubMed1996

An N-[(R)-(-)-2-hydroxypropionyl]-alpha-L-perosamine homopolymer constitutes the O polysaccharide chain of the lipopolysaccharide from Vibrio cholerae O144 which has antigenic factor(s) in common with V. cholerae O76.

Chemical and serological studies were performed with the lipopolysaccharide (LPS) from Vibrio cholerae O144 (O144). The LPS of O144 contained D-glucose, D-galactose, L-glycero-D-manno-heptose, D-fructose, D-quinovosamine (2-amino-2,6-dideoxy-D-gluco-pyranose) and L-perosamine (4-amino-4,6-dideoxy-L-manno-pyranose). The perosamine, a major component sugar of the LPS from O144, was in an L-configuration, as is also the case in the LPS from V. cholerae O76 (O76), in contrast to the D-configuration of the perosamine in the LPS of V. cholerae O1. A structural analysis revealed that the O polysaccharide chain of the LPS from O144 is an alpha(1-->2)-linked homopolymer of (R)-(-)-2-hydroxypropionyl-L-perosamine. The serological cross-reactivity between O144 and O76 was clearly revealed by cross-agglutination and cross-agglutinin absorption tests with whole cells, as well as by passive hemolysis tests with sheep red-blood cells that had been sensitized with the LPS from O144 and O76. In contrast, in passive hemolysis tests, the LPS of O144 did not cross-react serologically with the LPSs from other strains such as V. cholerae O1 (Ogawa and Inaba), V. cholerae O140, Vibrio bio-serogroup 1875 (Original and Variant) and Yersinia enterocolitica O9. The LPSs from these strains consist of O polysaccharide chains composed of alpha(1-->2)-linked homopolymers of D-perosamine with various N-acyl groups, and they share the Inaba antigen factor C of V. cholerae O1 in common. The results obtained in this study demonstrate that the absolute configuration of the perosamine residue in homopolymers plays a very important role in the expression of the serological specificity of the Inaba antigen factor C of V. cholerae O1.

Agglutination Tests↗