Biomedical subjects

M Kawagoe

Publications and source records attributed to M Kawagoe.

At least 19 recordsLinked to original sources

PubMed2001

Urinary copper excretion in type 2 diabetic patients with nephropathy.

BACKGROUND/AIMS: The aim of this study was to examine the relationship between the degree of urinary copper excretion and stages of diabetic nephropathy. METHODS: Copper, ceruloplasmin and albumin concentrations were measured in serum and urine samples from 41 type 2 diabetic outpatients with different stages of nephropathy and from 10 healthy controls. The copper/albumin and copper/ceruloplasmin ratios in serum and urine were determined. Furthermore, we examined whether free copper ions are dissociated from ceruloplasmin under various pH conditions. RESULTS: Urinary copper concentrations significantly increased only in macroalbuminuric patients. The copper/ceruloplasmin and copper/albumin ratios in urine were consistently greater than those in serum which were not different between patients and healthy controls except the copper/albumin ratio in macroalbuminuric patients. The ratios in urine decreased in parallel with the progression of nephropathy. Copper was found to be released from ceruloplasmin under acidic conditions. CONCLUSION: Urinary copper excretion in healthy controls may be the result of dissociation from the albumin-copper complex of serum during its passage through the kidney. In diabetic patients with advanced nephropathy, urinary copper excretion may be due to dissociations from both copper-albumin and ceruloplasmin-copper complexes filtered through the damaged glomerulus. Overloading of urinary copper to damaged renal tubules may play some roles in the progression of nephropathy in patients with advanced nephropathy.

Aged↗

PubMed2000

Refolding of target proteins from a "rigid" mutant chaperonin demonstrates a minimal mechanism of chaperonin binding and release.

One of the most interesting facets of GroEL-facilitated protein folding lies in the fact that the requirement for a successful folding reaction of a given protein target depends upon the refolding conditions used. In this report, we utilize a mutant of GroEL (GroEL T89W) whose domain movements have been drastically restricted, producing a chaperonin that is incapable of utilizing the conventional cyclic mechanism of chaperonin action. This mutant was, however, still capable of improving the refolding yield of lactate dehydrogenase in the absence of both GroES and ATP hydrolysis. A very rapid interconversion of conformations was detected in the mutant immediately after ATP binding, and this interconversion was inferred to form part of the target release mechanism in this mutant. The possibility exists that some target proteins, although dependent on GroEL for improved refolding yields, are capable of refolding successfully by utilizing only portions of the entire mechanism provided by the chaperonins.

Adenosine Triphosphate↗

PubMed2000

Attenuation of luminol-amplified chemiluminescent intensity and lipid peroxidation in the livers of quercetin-fed mice.

We assessed the antioxidative effects of quercetin-feeding on ddY strain male mice by measuring luminol-amplified chemiluminescence that was enhanced by a hydrophilic free radical initiator 2, 2'-azobis(2-amidinopropane) dihydrochloride. Quercetin suppressed chemiluminescent intensity in a dose-dependent manner in vitro with a half-inhibition concentration (IC(50)) of 3x10(-8) M, which was lower than the value of synthetic antioxidant 2, 6-di-tert-butyl-p-cresol (IC(50): 7x10(-7) M). Lysosomal (12000xg pellet) and supernatant fractions obtained from the livers of mice fed a diet containing 0.2% quercetin for 7 days showed more inhibition of chemiluminescent intensity than those from non-treated mice. Quercetin feeding also resulted in the inhibition of lipid peroxidation as determined by a thiobarbituric acid reactive substance test which detected suppression of the release of lysosomal enzymes induced by lipophilic free radical initiator 2, 2'-azobis(2,4-dimethylvaleronitrile). These results probably reflect radical quenching activity of quercetin, indicating that the measurement of chemiluminescence is a useful tool for the assessment of total antioxidant activity in biological systems.

Acetylglucosaminidase↗

PubMed1999

Functional communications between the apical and equatorial domains of GroEL through the intermediate domain.

The Escherichia coli GroEL subunit consists of three domains with distinct functional roles. To understand the role of each of the three domains, the effects of mutating a single residue in each domain (Y203C at the apical, T89W at the equatorial, and C138W at the intermediate domain) were studied in detail, using three different enzymes (enolase, lactate dehydrogenase, and rhodanese) as refolding substrates. By analyzing the effects of each mutation, a transfer of signals was detected between the apical domain and the equatorial domain. A signal initiated by the equatorial domain triggers the release of polypeptide from the apical domain. This trigger was independent of nucleotide hydrolysis, as demonstrated using an ATPase-deficient mutant, and, also, the conditions for successful release of polypeptide could be modified by a mutation in the apical domain, suggesting that the polypeptide release mechanism of GroEL is governed by chaperonin-target affinities. Interestingly, a reciprocal signal from the apical domain was suggested to occur, which triggered nucleotide hydrolysis in the equatorial domain. This signal was disrupted by a mutation in the intermediate domain to create a novel ternary complex in which GroES and refolding protein are simultaneously bound in a stable ternary complex devoid of ATPase activity. These results point to a multitude of signals which govern the overall chaperonin mechanism.

Adenosine Triphosphate↗

PubMed1999

The fragment of complement 3a lacking the primary 9 amino acids induces promoting activity on mouse voluntary running.

We have newly found that interleukin-2 (IL-2) increases mouse voluntary running 24 hours, but not 30 minutes, after the injection. We suspected that IL-2 induced a substance increasing the voluntary running for 24 hours after injection. Serum obtained from mice 24 hours after the IL-2 treatment was fractioned with the use of an ion-exchanger and an ultra-filtration method, and the amino acid sequence analysis indicated that the substance purified from the effective fraction was a fragment of mouse complement 3a (C3a) lacking the primary 9 amino acids. The 20 amino acid peptide synthesized according to the fragment showed the activity increasing the voluntary running, but the 20 amino acid peptide synthesized according to the C3a itself did not. The effect of the synthesized peptide was demuted by haloperidol but not by a specific dopamine 2 antagonist (-)sulpiride. The present findings clearly indicate that IL-2 produces the C3a fragment lacking the primary 9 amino acids which directly promotes the voluntary running, and that the effect of the fragment is mediated by an activity of haloperidol on the neurons, except for the dopamine 2 antagonism.

Amino Acid Sequence↗

PubMed1999

[Expression of brain-derived neurotrophic factor gene in retina following vitreous tap].

PURPOSE: Mechanical injuries to the retina following vitreous tap are reported to protect photoreceptor cells in a rat model of the retinal degeneration and enhance the survival rate of retinal ganglion cells in the optic nerve transection. Neurotrophic factors are presumably involved in the protective mechanisms. In order to see whether neurotrophic factors are synthesized in the retina, we studied the expression of neurotrophic factors in the retina following vitreous tap in rats. MATERIALS AND METHODS: One eye each of 20 mature rats received transscleral vitreous taps at three points of entry and retinal injury. The retinas were removed and examined at day 0 to 14 of treatment. RESULTS: Following injury, the retina showed increased expression of glial fibrillary acidic protein (GFAP) mRNA and brain-derived neurotrophic factor (BDNF) mRNA. There was no enhancement of neurotrophin-3 (NT-3) mRNA when examined by reverse transcription-polymerase chain reaction (RT-PCR). CONCLUSIONS: Activated retinal glial cells may produce BDNF which prevents retinal neuronal cell damage following injury.

Animals↗

PubMed1996

Platelet-derived growth factor B-chain homodimer suppressing a convulsion of epilepsy model mouse El.

El mouse is a mutant which has epileptic convulsions after tossing-up stimulations and has a hippocampal dysfunction. Platelet-derived growth factor B-chain homodimer has been reported to be a trophic factor of hippocampal neurons. We found that a recombinant PDGF-BB suppressed the convulsions of El mice in a dose-dependent manner. Furthermore, thrombin-treated mice manifested no convulsions, but thrombin receptor activating peptide-treated ones had convulsions. These findings suggest that an abnormality in PDGF-BB release may make El mice susceptible to tonic-clonic convulsions.

Animals↗

PubMed1996

Interleukin-1 alpha stimulates interstitial collagenase gene expression in human dental pulp fibroblast.

Interstitial collagenase (matrix metalloprotease-1) is a member of a family of matrix metalloproteases and is thought to play a role in degradation of the extracellular components, such as collagens in normal extracellular matrix remodeling and in many disease processes. We examined interstitial collagenase mRNA expression in human dental pulp fibroblast cultures by Northern blot analysis. These cells did not express interstitial collagenase mRNA in an unstimulated condition. Inflammatory cytokines, such as interleukin-1 alpha, induced interstitial collagenase mRNA expression in these cells. The interstitial collagenase mRNA levels began to increase after 2-h exposure, reaching a maximum after 8 h, then dropping to the unstimulated level at 48 h. These effects were observed in a dose-dependent manner in a dose range of 0.1 to 10 ng/ml. Transforming growth factor-beta reduced the levels of interstitial collagenase mRNA expression that were induced by interleukin-1 alpha. These observations suggest that interstitial collagenase mRNA expression in human dental pulp fibroblasts is regulated by the inflammatory cytokines and that interstitial collagenase may play a role in tissue degradation in inflamed dental pulp.

Adolescent↗

PubMed1996

Interleukin-8 gene expression by human dental pulp fibroblast in cultures stimulated with Prevotella intermedia lipopolysaccharide.

Interleukin (IL)-8 mRNA expression was investigated in human dental pulp fibroblast cultures after stimulation with lipopolysaccharide (LPS) prepared from Prevotella intermedia and inflammatory cytokines. The expression of IL-8 mRNA and the release of IL-8 induced by P. intermedia LPS in pulpal fibroblast cultures were detected by Northern blot analysis and ELISA, respectively. The sufficient concentration of P. intermedia LPS on the IL-8 mRNA expression was 0.1 microgram/ml in pulpal fibroblast cultures. IL-8 mRNA levels began to increase after 2 h of exposure, reached a maximum at 4 to 8 h, and declined after 48 h, reaching the unstimulated level by 60 h. IL-8 production by the pulpal fibroblasts began to increase after 8 h of exposure upon stimulation with 10 microgram/ml of P. intermedia LPS. By contrast Salmonella LPS and synthetic lipid A did not increase IL-8 mRNA concentrations in pulpal fibroblast cultures. Recombinant human IL-1 alpha, beta, and tumor necrosis factor-alpha were capable of stimulating these cells to express IL-8 mRNA but natural human interferon-beta, gamma, and recombinant human IL-6 were incapable in our assay. These results suggest that pulpal fibroblasts are immunoresponsive cells and can elaborate IL-8 upon stimulation with P. intermedia LPS.

Adolescent↗

PubMed1995

Microbial induction of dentinal caries in human teeth in vitro.

The ability of Lactobacillus casei, Streptococcus sobrinus, Actinomyces viscosus, and Streptococcus salivarius to induce dental caries was determined in vitro. A class I cavity (depth: 2mm) was prepared in extracted human caries-free premolars to make dentin blocks. The blocks were inoculated with these four bacterial strains in a monoinfective fashion and were incubated under anaerobic conditions. In addition to the monoinfection groups, mixed-infection groups of L. Casei with S. sobrinus or A. viscosus were also prepared. Half of the culture medium was renewed every 3 days, and the pH of the medium was measured. After 4 or 12 wk, these dentin blocks were prepared by Brown-Brenn staining and by contact microradiography for light microscopic observation and for immunohistochemical staining. The final pH of the S. salivarius group was the highest among the experimental groups, at approximately 5.1; that of the others was approximately 4.3. Bacterial invasion into the dentinal tubules was observed in all but the S. salivarius group. Among the monoinfection groups, the S. sobrinus group showed the highest invasion rate, followed by the A. Viscosus group and the L. casei group. The invasion rate was also high in the mixed-infection groups. Immunohistochemical staining revealed invasion only by L. casei, and not by S. sobrinus and A. viscosus. The invasion rate by L. casei was higher in the mixed-infection group with either S. sobrinus or A. viscosus than in the monoinfection groups. These findings suggest that lactobacillus might play an important role in the initiation and progress of dentinal caries, and that this bacterial species might exhibit a cooperative cariogenicity when it coexists with other bacterial species that surpasses its individual cariogenicity.

Actinomyces viscosus↗

PubMed1995

Bacterial invasion into dentinal tubules of human vital and nonvital teeth.

The difference in resistance to bacterial invasion into the dentinal tubules between vital and nonvital teeth has not been determined. This study was conducted to clarify the effect of vital pulp on bacterial invasion into the dentinal tubules. The specimens were 19 intact pairs of bilateral upper third molars of 19 healthy, young adult male volunteers. In each case, 30 or 150 days before extraction, pulpectomies and root canal fillings were carried out unilaterally and a class V cavity involving the dentin was made on the palatal surface of both the pulpectomized tooth and the nonpulpectomized opposite tooth. The cavities were left unprotected to expose them to oral flora until the extractions were done, and the extracted teeth were examined histologically. When extraction followed 150-day exposure to the oral flora, there was a statistically significant difference in the bacterial invasion rate between the vital and nonvital teeth. It was postulated that vital teeth were much more resistant to bacterial invasion into the dentinal tubules than were nonvital teeth, thereby suggesting that the vital pulp plays some important role in this process.

Adult↗

PubMed1995

Immunopathological activities of extracellular products of Streptococcus mitis, particularly a superantigenic fraction.

Previously, we prepared extracellular products, fractions F-1 and F-2 of Streptococcus mitis 108, an isolate from the tooth surface of an infant, and showed that F-1 exhibited inflammatory cytokine-inducing activities. In the present study, we present evidence that fraction F-2 induced human T-cell proliferation in the presence of irradiated human peripheral blood mononuclear cells and selectively activated T cells bearing V beta 2 and V beta 5.1 in the T-cell receptor. F-1, on the other hand, stimulated human gingival fibroblasts to support the T-cell proliferation in the same way as human gamma interferon or Prevotella intermedia lipopolysaccharide (LPS). Fraction F-1 also primed gingival fibroblasts to support the production of interleukin-2 and gamma interferon by the T cells upon stimulation with F-2. Human gingival fibroblasts stimulated with fraction F-1, like those stimulated by P. intermedia LPS and human gamma interferon, exhibited human leukocyte antigen (HLA)-DR mRNA expression and cell surface HLA-DR molecules as detected by enzyme-linked immunosorbent assay. An anti-HLA-DR monoclonal antibody inhibited T-cell proliferation in response to F-2, probably through inactivating the accessory function of HLA-DR-bearing fibroblasts. T cells activated with F-2 in the presence of irradiated peripheral blood mononuclear cells exhibited definite cytotoxic effects against fibroblasts and squamous carcinoma cells originating from human oral tissues. These findings are strongly suggestive of an association of extracellular products of viridans streptococci with pathogenesis of oral mucosal diseases, particularly those disorders in gingiva which are accompanied by heavy infiltration of T cells.

Antibodies, Monoclonal↗

PubMed1994

Interaction of interleukin-1 and interferon-gamma on fibroblast growth factor-induced angiogenesis.

The interaction of interleukin-1 (IL-1) and interferon-gamma (IFN-gamma) actions on several aspects of angiogenesis in vitro and in vivo was studied. The proliferation and migration of human umbilical vein endothelial cells cultured with basic fibroblast growth factor (bFGF) were synergistically inhibited by cotreatment with IL-1 and IFN-gamma. Endothelial cell adhesion to collagen was suppressed by IL-1 and the effect was slightly enhanced by the combination of IL-1 and IFN-gamma. Local administration of IL-1 (10,000 U) and IFN-gamma (1,000 U) inhibited bFGF-induced angiogenesis in the skin of mice, and synergistic inhibitory activity of the combination was demonstrated. Expression of FGF receptors was strongly downregulated by the combination, whereas expressions of epidermal growth factor (EGF) receptors, integrin beta 1 and integrin beta 3 were not. EGF partially abrogated the growth-inhibitory effects of IL-1 and IFN-gamma. These findings indicate that IL-1 and IFN-gamma are each able to act an angiogenesis inhibitor in a situation where FGF plays a major role in angiogenesis, and the activity is synergistically enhanced when they are used in combination.

Animals↗

PubMed1994

Immunobiological activities of a 55-kilodalton cell surface protein of Prevotella intermedia ATCC 25611.

A protein was extracted from whole cells of Prevotella intermedia ATCC 25611 with sodium lauroylsarcosine and purified by chromatography on a DEAE-Sepharose fast-flow column. The The apparent molecular weight of the protein was 55,000. A mouse polyclonal antibody specific for the protein recognized the cell surface structure of P. intermedia and also reacted with proteins in lysates of other black-pigmented anaerobic bacteria, such as Porphyromonas endodontalis and Prevotella melaninogenica, but not with those in lysates of Porphyromonas gingivalis or with the purified fimbriae of P. gingivalis 381. The N-terminal sequence of the 55-kDa protein showed only low homology with the cell surface proteins of any black-pigmented bacteria reported to date. The level of immunoglobulin G antibody to the antigen was higher in the sera of patients with periodontitis than in the sera of healthy volunteers. The protein induced interleukin-1 alpha, -1 beta, -6, and -8 and tumor necrosis factor alpha in human peripheral blood mononuclear cell cultures and interleukin-1 beta and -6 in human umbilical vascular endothelial cell and gingival fibroblast cultures. The protein induced interleukin-6 and tumor necrosis factor alpha activities in peritoneal macrophages from C3H/HeJ as well as from C3H/HeN mice and also induced cytokine activities in the sera of both strains of mice primed with muramyldipeptide.

Amino Acid Sequence↗

PubMed1994

Identification of antigenic epitopes in a surface protein antigen of Streptococcus mutans in humans.

The reactivities of antibodies in human serum and saliva to a cell surface protein antigen (PAc) of Streptococcus mutans and synthetic peptides covering the PAc molecule were examined. Both an enzyme-linked immunosorbent assay (ELISA) and Western blotting (immunoblotting) showed that all the serum samples from five adult subjects harboring serotype c S. mutans in their oral cavity reacted with recombinant PAc (rPAc). On the other hand, the serum from a 4-month-old infant did not react with rPAc in ELISA. The immunoglobulin A (IgA) antibodies in saliva samples from the five adult subjects reacted with rPAc. However, in saliva samples from these subjects, the titers of IgA antibody to rPAc did not correlate with the titers of serum antibody to the antigen. To map continuous antigenic epitopes in the PAc molecule, we synthesized 153 decapeptides covering the entire mature PAc molecule, 121 overlapping decapeptides covering the alanine-rich repeating region (A-region) of the PAc molecule, and 21 overlapping decapeptides covering the middle region (residues 824 to 853) according to multiple pin-coupled peptide synthesis technology. Of 153 decapeptides covering the mature PAc, 27 decapeptides showed a strong reaction with the antibodies in serum from the adult subjects. The epitope-scanning patterns in the serum samples from these subjects were also very similar to each other. The antigenic epitope patterns in the saliva resembled those in the serum. However, the ELISA titers of salivary IgA antibodies to these decapeptides differed from the titers of the serum antibody. Of the 121 overlapping decapeptides covering the A-region, 27 decapeptides showed a positive reaction with the antibodies in serum from the adult subjects. All of these 27 decapeptides had either one or two of the five common sequences YQAXL, NADAKA, VQKAN, NNAKNA, and IKKRNA. Six decapeptides of the 21 overlapping decapeptides covering the middle region reacted strongly with the serum antibodies from a high PAc responder, and each of the six decapeptides had one of the two common sequences KVTKEKP and VKPTAPTK. These epitopes might therefore be relevant to the humoral responses against the PAc protein during natural infection with S. mutans in humans.

Adult↗

PubMed1994

Increased endothelin-1 production in fibroblasts derived from patients with systemic sclerosis.

OBJECTIVES: To determine whether fibroblasts from patients with systemic sclerosis (SSc) produce excessive amounts of endothelin-1 (ET-1), which is recognised as having vasoconstrictive properties and as having a potent mitogenic effect on fibroblasts. METHODS: Dermal fibroblasts were removed from 11 patients with SSc and from five normal controls (NC). The assay of ET-1 protein was measured by an ELISA that used two anti-ET-1 antibodies. The gene expression of prepro ET-1 mRNA was evaluated by a reverse-transcriptase polymerase chain reaction (RT-PCR) method. RESULTS: Levels of ET-1 protein were significantly higher in SSc fibroblast cultures than in those of normal fibroblasts (p < 0.01). The expression of prepro ET-1 mRNA was also higher in SSc fibroblasts than in normal fibroblasts. The addition of interleukin-1 beta (IL-1 beta) increased the production of ET-1 by fibroblasts. CONCLUSION: The findings indicate that the overproduction of ET-1 is a novel abnormal function in SSc fibroblasts, and that ET-1 induced by fibroblasts may play a role in the fibrosis and Raynaud's phenomenon of SSc.

Adult↗

PubMed1994

[A case of systemic lupus erythematosus presenting with myelofibrosis as a cause of pancytopenia].

A 54 year-old woman who had a 6 month history of polyarthralgias, oral ulcers, weight loss and fatigue was admitted to the Urawa Municipal Hospital. She developed high fever, dyspnea and thrombocytopenia. Chest radiograph revealed massive right pleural effusion. At this time, laboratory investigations gave the following results: hemoglobin 12.7 g/dl, WBC 7700/microliters and platelet count 9.2 x 10(4)/microliters. Antibody to DNA was negative. Antinuclear antibody was positive at a titer of 320x in a centromere pattern; Anti-RNP and anti-Sm antibodies were negative. CH50 was 18.6 u/ml. C3 was 42.9 mg/dl. C4 was 11.5 mg/dl. Circulating immune complex (Clq) was 30.5 micrograms/ml. Circulating lupus anti-coagulant and anticardiolipine antibodies were positive. Thoracocentesis was performed; the material was a straw-colored exudate with over two thousands white cell per ul and showed marked reduction of complement titiers and elevated immune complex levels. She was then diagnosis as having SLE. Two weeks after admission, progressive leukopenia and anemia succeedingly occurred and resulted in severe pancytopenia. Bone marrow biopsy demonstrated marked marrow fibrosis and increased reticulin content with no evidence of malignancy. Steroid pulse therapy for 3 days started, and subsequently she was treated with 60 mg/day of prednisolone. Three weeks after starting on steroids, the massive pleural effusion was completely disappeared and complement titiers were normalized. Circulating immune complex has not been detected any more. After 8 weeks, the peripheral blood count was normalized. The dose of prednisolone was reduced progressively. On this occasion, the biopsy showed normocullular marrow with a marked reduction in the amount of reticulin.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Antinuclear↗

PubMed1994

Myelodysplastic syndrome associated with immunoblastic lymphadenopathy-like T-cell lymphoma: simultaneous clinical improvement with chemotherapy.

A 75-year-old woman presented with anemia, lymphadenopathy, hepatomegaly and lingual tumor, but no constitutional symptoms. The laboratory data showed pancytopenia and polyclonal hypergammaglobulinemia. A bone marrow aspirate represented an apparent myelodysplastic syndrome (MDS) feature, specifically, refractory anemia with excess of blasts. A lymph-node biopsy revealed the disappearance of normal architecture, small arborizing blood vessels, large lymphoid cells with prominent cytoplasm (so-called pale cells) and a clonal proliferation of T-lymphocytes. The patient was diagnosed as having MDS associated with immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma. She was subsequently treated with cyclophosphamide, adriamycin, vincristine and prednisolone for lymphoma which successfully induced a remission of not only the T-cell lymphoma but also the MDS. The case suggested that MDS might be a paraneoplastic complication of IBL-like T-cell lymphoma.

Aged↗