Biomedical subjects

N Ishiguro

Publications and source records attributed to N Ishiguro.

At least 55 records · Page 3Linked to original sources

PubMed1999

Genetic relationship and distribution of the Japanese wild boar (Sus scrofa leucomystax) and Ryukyu wild boar (Sus scrofa riukiuanus) analysed by mitochondrial DNA.

Mitochondrial genetic variations were used to investigate the relationships between two Japanese wild boars, Japanese wild boar (Sus scrofa leucomystax) and Ryukyu wild boar (S.s. riukiuanus). Nucleotide sequences of the control (27 haplotypes) and cytochrome b (cyt-b) regions (19 haplotypes) were determined from 59 Japanese wild boars, 13 Ryukyu wild boars and 22 other boars and pigs. From phylogenetic analyses, the mtDNA of Ryukyu wild boar has a distinct lineage from that of Japanese wild boar, which was classified into the Asian pig lineage. This result suggests that the Ryukyu wild boar has a separate origin from the Japanese wild boar.

Animals↗

PubMed1999

The effect of da-fang-feng-tang on treatment of type II collagen-induced arthritis in DBA/1 mice.

Da-Fang-Feng-Tang (DFFT), which is believed to be effective for treating human rheumatoid arthritis (RA), was given to DBA/1 mice at the onset of type II collagen-induced arthritis (CIA) to examine its effect. Granules of the crude DFFT extract were administered by gastric gavage at a dose of 1.6 g/kg/day for 12 weeks, starting the day CIA began. The levels of anticollagen IgG antibody were significantly decreased in the sera of the DFFT-treated group compared with the control group from weeks 2 to 7 after the onset of CIA. The severity of arthritis in the DFFT-treated group was markedly alleviated when compared with the control group. In addition, histological examination of the DFFT-treated group showed less cartilage and bone erosion. These results suggest that administration of DFFT suppressed the development of CIA in mice and support the belief that DFFT is effective in treating human RA.

Animals↗

PubMed1999

The SHAP-HA complex in sera from patients with rheumatoid arthritis and osteoarthritis.

OBJECTIVE: To investigate serum derived hyaluronan (HA) associated protein-hyaluronan (SHAP-HA) complex in sera from patients with rheumatoid arthritis (RA) and osteoarthritis (OA) and determine levels of the complex in comparison with those of hyaluronan (HA), in order to assess the role of the complex as an indicator of joint inflammation. METHODS: ELISA and HA binding assays were used for quantitation of the SHAP-HA complex and HA levels in serum samples from 142 patients (114 with RA, 28 with OA) and 31 healthy controls. Clinical evaluations were also performed. RESULTS: In some RA sera, SHAP-HA complex levels were extremely high compared to control levels, but in OA sera no marked increase was observed compared to controls. This was also the case with the HA levels compared between RA and OA sera. However, in RA the levels of the SHAP-HA complex appear to be more related to clinical variables than are levels of HA, and the most significant correlations between levels of SHAP-HA complex and HA were found in the RA group. CONCLUSION: Quantitation of the SHAP-HA complex in sera may be useful as a joint marker that directly correlates to the degree of joint inflammation in RA, and offers new insight into the pathogenesis of arthritis. It may also serve as an independent criterion in the subsequent classification of RA and OA.

Adult↗

PubMed1999

Effects of sodium hyaluronate on experimental osteoarthritis in rabbit knee joints.

The aim of this study was to examine the effects of intraarticular administration of hyaluronan (HA) on cartilage degradation. Using a partial menisectomy model of osteoarthritis (OA) in the rabbit knee, the authors investigated the catabolic and anabolic changes induced by intraarticular injection of HA. To analyze anabolic changes, the authors assessed cell proliferation by measuring [3H] thymidine uptake, and proteoglycan biosynthesis by noting [35S] sulfate incorporation. For catabolic changes, messenger ribonucleic acid (mRNA) expression of interstitial collagenase (MMP-1), stromelysin-1 (MMP-3), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in cartilage and synovium were detected with reverse transcriptase polymerase chain reaction (RT-PCR). Of significance for blocking the development of early OA in chondrocytes was the finding that total proteoglycan synthesis in the HA treatment group was significantly higher than in the controls. At the mRNA level in cartilage and synovium, HA inhibited MMP-3 and TIMP-1 production in the same way in the HA treatment group, while not affecting MMP-1 production. Thus it can be concluded that HA affects cartilage catabolism and anabolism to prevent the progress of OA.

Animals↗

PubMed1999

Effects of vector-averaged gravity on NF-kappa B activation in human osteoblast-like cells.

We have recently demonstrated that a transcription factor, nuclear factor kappa B (NF-kappa B), plays a key role in the production of cytokine and cell adhesion molecules in osteoblastic cells. In the present study, we investigated the effects of vector-averaged gravity (clinostat rotation) on tumor necrosis factor (TNF)-alpha-induced activation of NF-kappa B in human osteoblastic HOS-TE85 cells. After a 72-hr clinostat culture, the cells were treated with TNF-alpha for 30 min. Electrophoretic mobility shift assay using the nuclear extracts revealed that the DNA-binding activity of NF-kappa B was substantially reduced in clinostat-cultured cells compared with the stationary control. Concomitantly, the transactivation of NF-kappa B was examined by a transfection study. The cells were transfected with a plasmid expressing a luciferase reporter gene driven by multimerized NF-kappa B sites. They were cultured in the clinostat for 48-hr, followed by a 4-hr treatment with TNF-alpha. Clinostat culture resulted in a significant decrease in the luciferase activities, being consistent with the decreased binding of NF-kappa B. These results indicate that exposure of HOS-TE85 cells to vector-averaged gravity impairs NF-kappa B activation by TNF-alpha.

DNA↗

PubMed1999

Matrix metalloproteinases, tissue inhibitors of metalloproteinases, and glycosaminoglycans in synovial fluid from patients with rheumatoid arthritis.

OBJECTIVE: To investigate the correlation between synovial fluid (SF) concentrations of metalloproteinase (MMP) -2, -3, and -9, tissue inhibitors of metalloproteinases (TIMP)-1 and -2, chondroitin 4-, 6-sulfate (deltadi-C4S, deltadi-C6S), hyaluronic acid (deltadi-HA), antigenic keratan sulfate (KS), and radiologic grade in patients with rheumatoid arthritis (RA) and to assess the clinical value of these factors as disease markers. METHODS: Enzyme linked immunoassays and high performance liquid chromatography were used. SF samples were collected from 52 patients with RA. Radiographic (Larsen grade) and clinical evaluations were also done. RESULTS: There was no significant correlation between the concentrations of MMP, TIMP, and deltadi-C4S, deltadi-C6S, deltadi-HA, and antigenic KS. No significant correlations were found between the radiologic grade and the concentrations of MMP or TIMP in SF. There was a significant increase in the concentration of antigenic KS and deltadi-C6S/deltadi-C4S ratio in SF from patients with Larsen grade 2 compared to grade 5. A significant correlation between deltadi-C6S and antigenic KS concentrations in SF was observed. CONCLUSION: Although there were large variances between the samples in this study, proteoglycan metabolism in the cartilage matrix of the patients with RA might have been increased in the early phases of tissue destruction and decreased in advanced stages because of scanty cartilage tissue. The concentrations of MMP-2, -3, -9 and TIMP-1, -2 in SF did not seem to be influenced by the amount of residual cartilage.

Aged↗

PubMed1998

Differences in the evolutionary pattern of feline panleukopenia virus and canine parvovirus.

Canine parvovirus (CPV) suddenly appeared in the late 1970s after which it showed continuous antigenic changes. Virological and molecular genetic analyses mainly focused on feline panleukopenia virus (FPLV) were conducted in this study because FPLV is the suspected ancestor of CPV; the way in which FPLV evolves may help to explain the emergence of CPV. Analysis of escape mutants against FPLV-specific monoclonal antibody showed that viruses possessing CPV-like properties were not easily detected in FPLV virus stocks. Phylogenetic analysis revealed that the nonstructural protein 1 (NS1) and capsid protein 2 (VP2) genes of FPLV changed with time. A similar tendency, however, was not observed in the FPLV VP2 proteins. In contrast, the topology of the phylogenetic tree of VP2 proteins of CPV basically concurred with that of the VP2 genes. Analysis of the ratio of nonsynonymous and synonymous substitutions revealed that synonymous substitutions exceeded nonsynonymous substitutions in both the NS1 and VP2 genes of FPLV, even when the analysis focused on specific regions in the VP2 gene that are known to be located on the capsid surface. Comparison of the CPV VP2 genes revealed that nonsynonymous substitution was found to dominate over synonymous substitution in one specific region in the VP2 gene. These results suggested that FPLV has changed mainly by random genetic drift. In contrast, after the appearance of CPV, changes in the CPV VP2 gene appear to be partly selected by certain positive selection forces. CPV and FPLV are known to be closely related viruses genetically and biologically, but the evolutionary mechanisms of the two viruses appeared to be different.

Amino Acid Substitution↗

PubMed1998

The regulation of murine H-2Dd expression by activation transcription factor 1 and cAMP response element binding protein.

Resistance to radiation leukemia virus (RadLV)-induced leukemia is correlated with an increase in H-2Dd expression on the thymocyte surface. It has been shown that elevated H-2Dd expression on infected thymocytes is a result of elevated mRNA transcription and that the transcriptional increase is correlated with elevated levels of a DNA binding activity, H-2 binding factor 1 (H-2 BF1), which recognizes the 5'-flanking sequence (5'-TGACGCG-3') of the H-2Dd gene. Recently, it has been shown that the activation transcription factor 1 (ATF-1) homodimer is one form of the H-2 BF1 complex. Here we demonstrate that the cAMP response element binding protein (CREB) homodimer and the heterodimer of CREB/ATF-1 also recognize the cis regulatory motif and are two additional forms of the H-2 BF1 complex. The levels of mRNA encoding ATF-1 and CREB were both increased in RadLV-infected thymocytes that showed increased levels of H-2 mRNA. Also, all three H-2 BF1 binding activities, ATF-1 homodimer, CREB homodimer, and ATF-1/CREB heterodimer, were increased in RadLV-infected thymocytes that expressed high levels of H-2Dd Ag on the cell surface. Transfection experiments demonstrated that ATF-1 and CREB activated a reporter plasmid containing the H-2 BF1 motif. These observations strongly suggest that both ATF-1 and CREB are involved in the regulation of H-2 gene expression following RadLV infection of mouse thymocytes.

Activating Transcription Factor 1↗

PubMed1998

Characterization of differentially expressed genes in the bovine T lymphoma cell line.

A differential display (D.D.) analysis was made to detect differentially expressed genes in a bovine T lymphoma cell line, BTL-26, derived from the calf type of sporadic bovine lymphosarcoma. A D.D. analysis comparing BTL-26 with the bovine epithelial cell line CKT-1 and healthy bovine thymocytes yielded 24 cDNA clones. The DNA sequencing analysis followed by a homology search showed that 20 of the 24 cDNA clones had no significant homology to any sequences in DNA data base. The remaining four genes were homologous to known sequences. Northern blot hybridization among BTL-26, CKT-1 and healthy bovine thymocytes showed that a cDNA clone, BC8, was differentially expressed in BTL-26. The cloning of full-length cDNA for the BC8 clone and its DNA sequences showed that the BC8 clone is a bovine nuclear domain protein homologous to the human NDP52 gene. Northern blot analysis showed that the BC8 clone bovine NDP52 was predominantly expressed in tumor cell line BTL-26, compared with the transcripts from several bovine tissues.

Amino Acid Sequence↗

PubMed1998

Up-regulation of COX2 expression by uni-axial cyclic stretch in human lung fibroblast cells.

The effect of uni-axial cyclic mechanical stretch on the expression of cyclooxygenases (COX) was investigated in a human lung fibroblast cell line (TIG-1). In response to uni-axial cyclic stretch, the level of COX2 mRNA significantly increased and peaked at 3 h (9.09 +/- 3.82-fold, mean +/- standard error, n = 6, compared with that at 1 h). The level of the expression of COX2 protein peaked at 6 h, whereas the level of COX1 protein was not significantly changed. The involvement of stretch-activated (SA) channel was investigated in the stretch-induced COX2 production. The application of Gd3-, a blocker for SA channel, or the removal of extracellular Ca2+ inhibited the production of COX2 mRNA without any effect on the production of COX1 or GAPDH mRNA. These data strongly suggest that COX2 expression is up-regulated by uni-axial cyclic stretch via the activation of SA channel in human lung fibroblasts.

Calcium↗

PubMed1998

Increased pentosidine, an advanced glycation end product, in plasma and synovial fluid from patients with rheumatoid arthritis and its relation with inflammatory markers.

Pentosidine is an advanced glycation end product (AGE) formed by combined processes of glycation and oxidation (glycoxidation) between carbohydrate-derived carbonyl group and protein amino group. Recent studies demonstrated the increased pentosidine levels not only in diabetic patients with hyperglycemia but also in normoglycemic uremic patients due to increased oxidative stress. Rheumatoid arthritis (RA) is a state of increased oxidative stress associated with chronic inflammation. This suggested an enhanced glycoxidation reaction and increased AGE levels in RA patients. In the present study, we therefore determined, by high performance liquid chromatographic (HPLC) assay, the concentrations of pentosidine in plasma and synovial fluid from 22 patients with rheumatoid arthritis (RA) and compared their levels with those in 17 patients with osteoarthritis (OA), 26 diabetic patients, and 25 normal subjects. The levels of inflammatory markers and markers of tissue destruction, metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), were also measured in the same samples. Pentosidine levels in plasma and synovial fluid from RA patients were significantly higher than those in OA patients, diabetic patients, and normal subjects. There was a significant correlation between the pentosidine levels in plasma and those in synovial fluid. Among markers of inflammation and matrix destruction, pentosidine levels in plasma from RA patients were correlated with the levels of C-reactive protein (CRP), erythrocyte sedimentation rate, white blood cell count, and platelet count. Multiple stepwise regression analysis reveals an independent influence of CRP on plasma pentosidine levels. In conclusion, pentosidine levels are significantly higher in plasma and synovial fluid from RA patients and may be useful as a biomarker of chronic inflammation in RA patients.

Acute-Phase Proteins↗

PubMed1998

Characterization of the sheep apolipoprotein E (ApoE) gene and allelic variations of the ApoE gene in scrapie Suffolk sheep.

Apolipoprotein E (ApoE) plays a central role in lipid transport and is suggested to be involved in neuronal repair. Human ApoE epsilon 4 allele is known as a risk factor for Alzheimer's disease, and an association of the human ApoE genotype with the human prion disease, Creutzfeldt-Jakob disease, is suggested, albeit controversial. We analyzed the sheep ApoE gene to determine whether any association between the sheep ApoE genotype and the sheep prion disease, scrapie, existed. The sheep ApoE cDNA contained an open reading frame (ORF) consisting of 948 base pairs (bp) that encoded 316 amino acids (aa). The sheep ApoE gene was composed of four exons separated by three introns, and the ORF was encoded by three exons, designated exons 2, 3, and 4. Nucleotide sequence analysis also showed the presence of one G/T nucleotide polymorphism in the ORF that resulted in an Ala/Ser amino-acid substitution at codon 258. PCR-restriction fragment length polymorphism analysis of genomic DNA showed the presence of three sheep ApoE genotypes that were the result of the homologous and heterologous combinations of the two alleles. We analyzed the sheep ApoE genotypic and the allelic frequencies in scrapie and control Suffolk sheep, but they did not significantly differ from those in the control sheep, even though PrP genotype-matched populations were compared. The ApoE genotype appeared not to be associated with the progression of the disease when looking at the age at death. These results indicated that in Suffolk sheep, none of the ApoE genotypes was associated with scrapie.

Alleles↗

PubMed1998

The retention of abnormal type I procollagen and correlated expression of HSP 47 in fibroblasts from a patient with lethal osteogenesis imperfecta.

Various mutations of genes encoding type I procollagen chains have been linked to osteogenesis imperfecta (OI). The mutations yield abnormal procollagen molecules that fold improperly. HSP 47, a stress-inducible protein localized to the endoplasmic reticulum (ER) of collagen-producing cells, may participate in collagen processing as a procollagen-specific molecular chaperone. The intracellular transport of abnormal procollagen molecules and the expression of HSP 47 have been studied in fibroblasts from a patient with OI. Normal and OI fibroblasts cultured with or without ascorbate were analysed by immunofluorescent double labelling with monoclonal antibodies to C-propeptide of type I procollagen and HSP 47, as observed by confocal microscopy. Procollagen and HSP 47 were also quantified by immunoprecipitation of normal and OI fibroblasts radiolabelled with 35S-methionine. By confocal microscopy, procollagen molecules were retained in the ER of both fibroblast types cultured in the absence of ascorbate, and were co-localized with HSP 47. In normal fibroblasts, 2 h after the addition of ascorbate, most of the procollagen had disappeared from the cells, while in OI fibroblasts, abnormal procollagen molecules and HSP 47 were still retained in the ER. By immunoprecipitation, procollagen was negligible in normal fibroblasts cultured with ascorbate; much larger amounts of procollagen were immunoprecipitated from OI fibroblasts despite ascorbate. Increased HSP 47 in OI fibroblasts was demonstrated by immunoprecipitation with a specific monoclonal antibody. These results suggest the increase in HSP 47 in the ER of OI fibroblasts is related to its collagen-specific chaperone function.

Ascorbic Acid↗

PubMed1998

Genomic structure of the bovine PrP gene and complete nucleotide sequence of bovine PrP cDNA.

The present authors previously reported the nucleotide sequence of the 5' half of a cDNA encoding bovine prion protein (PrP) and the genomic structure of the bovine PrP gene encoding the 5' -untranslated region. Here they report the extent of intron 2 of the bovine PrP gene and the nucleotide sequence of the 3' half of bovine PrP cDNA that had not been determined before. This newly sequenced 3' half of the bovine PrP cDNA consisted of 2149 bp. The entire 3'-untranslated region (3'-UTR) was found to be encoded by a single exon, exon 3. One nucleotide polymorphism was found in the 3'-UTR. The length of intron 2 was estimated to be about 14 kbp. The structure of bovine PrP gene can be defined by combining the present results and previous reports on the bovine PrP gene.

Animals↗

PubMed1998

The surgical treatment of a haemophilic pseudotumour in an extremity: a report of three cases with pathological fractures.

A haemophilic pseudotumour is a rare complication of haemophilia occurring in 1-2% of patients with a factor VIII or IX deficiency. This report presents three surgical cases of pseudotumours involved in a pathological fracture in the extremities. All cases showed a favourable post-operative course. If the preoperative management is appropriately designed, a limb salvage operation for a pathological fracture due to a pseudotumour could be carried out successfully. Before choosing amputation of a limb, the surgeon should consider the possibility of limb salvage.

Adult↗

PubMed1998

Selective neutrophil depletion with monoclonal antibodies attenuates ischemia/reperfusion injury in skeletal muscle.

The purpose of this study was to determine whether depletion of circulating neutrophils, using an antineutrophil monoclonal antibody (RP3), would attenuate ischemia/reperfusion injury in rat skeletal muscle. A 3- and 5-hr period of ischemia was induced unilaterally into the hindlimbs of rats; the isolated limbs were then reperfused for 24 hr after ischemia. The gastrocnemius muscle was then removed, and blood was taken simultaneously. The hematologic parameters were measured, muscle neutrophil sequestration was assessed by myeloperoxidase (MPO) activity, free radical production was evaluated by the tissue lipid peroxides (LPO) levels, muscle viability was assessed by tissue levels of adenosine triphosphate (ATP) and creatine phosphate (PCr) levels, and muscle wet/dry weights were determined. Treatment with RP3 selectively and sufficiently depleted the circulating neutrophil population, markedly reduced MPO, and significantly attenuated LPO and the tissue water content after both 3- and 5-hr of ischemia. After 3 hr of ischemia, ATP and PCr levels were significantly increased by neutrophil depletion; however, after 5 hr of ischemia, the same effect was not demonstrated. These results suggest that neutrophil depletion after 3 hr of ischemia restrains free radical production and edema formation, and also attenuates skeletal muscle ischemia reperfusion injury; however, after 5 hr of ischemia, ischemic damage was so severe, that neutrophil depletion did not reduce ischemia reperfusion injury.

Adenine Nucleotides↗

PubMed1998

Rapid analysis of allelic variants of the sheep PrP gene by oligonucleotide probes.

A rapid method to determine the allelic variants of the sheep PrP gene was developed. DNA samples from 128 Suffolk sheep (39 rams and 89 ewes) were screened by using polymerase chain reactions and dot-blot hybridization with 32P-labeled nine allele-specific oligonucleotide probes corresponding to the polymorphic PrP codons 112, 136, 154 and 171. Three allelic variants of the PrP gene, PrP(MARQ), PrP(TARQ) and PrP(MARR), were found in the flocks. Among those variants, nearly half of the ewes had alleles of the 171-Arg variant that is closely associated with resistance to natural scrapie. Assessments of allelic mutations of the PrP gene may help to select the scrapie-resistant progenitors in the flocks.

Alleles↗

PubMed1998

TNF-alpha increases expression of IL-6 and ICAM-1 genes through activation of NF-kappaB in osteoblast-like ROS17/2.8 cells.

Tumor necrosis factor-alpha (TNF-alpha) plays a key role in inflammatory diseases such as rheumatoid arthritis and in postmenopausal osteoporosis. In various tissues, TNF-alpha action is mediated by a transcription factor, nuclear factor-kappa B (NF-kappaB). However, little is known about how TNF-alpha exerts its action in osteoblasts. We thus examined the effect of TNF-alpha on the activation of NF-kappaB in rat osteoblast-like osteosarcoma cells (ROS17/2.8). Electrophoretic mobility shift assay revealed that the activation of the p50-p65 heterodimer NF-kappaB was induced by TNF-alpha as early as 15 minutes followed by a persistent activation for 48 h. When the binding activity of NF-kappaB in cytosol was examined using detergents that dissociate NF-kappaB from an inhibitory protein IkappaB, it decreased during the initial 30 minutes and then increased to the unstimulated level. Northern blot analysis revealed a marked increase in the mRNA levels of p105, a precursor of p50, 6 h after TNF-alpha and a gradual increase in p65 mRNA levels during the initial 1 h. Significant increase in both mRNA levels continued until 24 h after TNF-alpha. These results suggest that the rapid activation of NF-kappaB by TNF-alpha is mainly due to the nuclear translocation of NF-kappaB pre-existing in cytosol, and that the subsequent increase in the expression of p50 and p65 may result in the persistent activation of NF-kappaB during TNF-alpha stimulation. TNF-alpha also increased the mRNA levels of interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1). An antioxidant, N-acetyl-L-cysteine, significantly attenuated the TNF-alpha-dependent increase in these mRNAs, and simultaneously reduced the activation of NF-kappaB by TNF-alpha, indicating that NF-kappaB mediates the TNF-alpha-dependent expression of IL-6 and ICAM-1 in ROS17/2.8 cells. These results suggest that the activation of NF-kappaB by TNF-alpha may play an important role in the production of cytokines and cell adhesion molecules from osteoblasts, leading to the promotion of bone resorption and inflammation.

Acetylcysteine↗