Biomedical subjects

H Noguchi

Publications and source records attributed to H Noguchi.

At least 19 recordsLinked to original sources

PubMed1992

Determination of gliclazide in serum by high-performance liquid chromatography using solid-phase extraction.

A simple and sensitive high-performance liquid chromatographic method for a routine assay of gliclazide in serum is described. Serum samples spiked with glibenclamide (internal standard) were applied to Bond Elut C18 cartridges. After washing with phosphate buffer (pH 7.5) and water, the cartridge was eluted with 60% methanol. The eluate was evaporated to dryness. The residue was dissolved in methanol and injected onto an octadecyl silica column (5 microns, 150 mm x 4.6 mm I.D.). The mobile phase was 0.04 M potassium dihydrogenphosphate (pH 4.6)-acetonitrile-isopropyl alcohol (5:4:1, v/v). Ultraviolet detection at 227 nm was used. The minimum detectable level of gliclazide was 20 ng/ml.

Chromatography, High Pressure Liquid↗

PubMed1992

13C-NMR spectral analysis of the structures of mouse immunoglobulin G1 carrying allotypes a and j.

A novel 13C nuclear magnetic resonance (NMR) method is described for the detection of subtle structural differences between mouse immunoglobulins carrying different allotypes. Fc fragments of mouse IgG1 antibodies carrying allotypes a and j have been selectively labeled with [1-13C]methionine. 13C-NMR spectra have shown that the microenvironment around Met-398 is significantly different for the two kinds of allotypes. Peptide mapping and amino acid sequence analyses have revealed that Val-406 of IgG1 carrying allotype a is substituted for Ile in the case of allotype j. X-ray crystallographic data indicate that Met-398 is in close spatial proximity to Val (Ile)-406. We therefore conclude that the 13C-NMR method can provide us with a novel spectroscopic probe for the structural characterization of allotypic markers.

Amino Acid Sequence↗

PubMed1992

Monoclonal antibodies against Pseudomonas aeruginosa elastase: a neutralizing antibody which recognizes a conformational epitope related to an active site of elastase.

We have established seven murine hybridoma cell lines which produce monoclonal antibodies (mAbs) against Pseudomonas aeruginosa elastase. The seven mAbs recognized at least six different epitopes on the elastase molecule. All mAbs inhibited both enzymatic activities of elastase and protease, in which elastin fluorescein and hide powder azure were used as substrates, respectively. One of them, mAb E-4D3, strongly neutralized enzymatic activities of peptidase in which furylacryloyl-glycyl-leucinamide was used as a substrate, as well as of elastase and protease. In contrast, the other six mAbs did not neutralize peptidase activity at all. The Ki value for furylacryloyl-glycl-leucinamide of E-4D3, as well as its Fab fragment, was comparable to those for metalloprotease inhibitors such as phosphoramidon and Zincov inhibitor. The binding of mAb E-4D3 was inhibited by phosphoramidon and Zincov inhibitor, but not by metal chelators such as EDTA and o-phenanthroline. A line of evidence suggests that mAb E-4D3 directly interacts with active site and highly neutralizes enzymatic activity of P. aeruginosa elastase. Data of Western blotting and ELISA suggest that mAb E-4D3 is likely to recognize an elastase molecule in a conformation-dependent manner as an epitope. In contrast, the neutralizing activity of the other mAbs against elastase and protease seems to be caused by a low accessibility of an enzyme to insoluble and high-molecular-mass substrates through the binding and steric hindrance of the mAbs to an enzyme.

Amino Acid Sequence↗

PubMed1992

Determination of nadolol in serum by high-performance liquid chromatography with fluorimetric detection.

A sensitive high-performance liquid chromatographic method for a routine assay of nadolol in serum is described. Serum samples spiked with atenolol (internal standard) were extracted with diethyl ether. After centrifugation, the organic layer was evaporated to dryness. The residue was redissolved in the mobile phase and injected onto an octadecyl silica column (150 mm x 4.6 mm I.D.). The mobile phase was 0.05 M ammonium acetate (pH 4.5)-acetonitrile (85:15, v/v). Fluorometric detection (excitation 230 nm, emission 300 nm) was used. The minimum detectable level of nadolol in serum was 1 ng/ml.

Atenolol↗

PubMed1992

Endorectal pull-through operation for diffuse cavernous hemangiomatosis of the sigmoid colon, rectum and anus.

A 6-year-old girl with diffuse cavernous hemangiomatosis of the sigmoid colon, rectum and anus underwent endorectal pull-through operation for sphincter-saving resection. Rectal mucosa was resected from 4 cm above peritoneal reflection to anal skin margin and the normal sigmoid colon was pulled down through the rectal muscular cuff. Ligation of the superior rectal and left internal iliac arteries at operation achieved satisfactory control of bleeding. Postoperative manometric studies showed almost normal sphincter tone and good response to rectal stimuli by balloon inflation. The endorectal pull-through (Soave-Denda procedure) is a common procedure for Hirschsprung's disease and the best procedure for the sphincter-saving treatment of diffuse cavernous hemangiomatosis of the colon and rectum.

Anal Canal↗

PubMed1992

Morphological and functional changes of islets of Langerhans in FK506-treated rats.

FK506, a new immunosuppressant, caused glucose intolerance in rats given daily oral doses of 1, 5, or 10 mg/kg/day for 14 days, but did not induce hyperglycemia under normal feeding. Besides the glucose intolerance, insulin secretion was impaired and insulin levels in the pancreas were lowered. Histopathologically, there was vacuolation of the Langerhans islets in the animals given 10 mg/kg. After withdrawal of the drug, these changes in pancreatic function and morphology returned to normal within 2 weeks. The findings indicate that FK506 caused dose-dependent but reversible islet toxicity in rats.

Animals↗

PubMed1992

The effects of FK506 and cyclosporine on the exocrine function of the rat pancreas.

The effects of FK506 on exocrine function of the pancreas in Sprague-Dawley rats were examined and compared with those of cyclosporine. FK506 did not affect the levels of amylase and lipase in the pancreas of rats given the drug orally in a daily dose of 1 or 5 mg/kg for 2 weeks. Furthermore, the pancreas of the rats showed good exocrine secretion of enzymes such as amylase and lipase on stimulation with carbachol in vitro. Cyclosporine 50 mg/kg given in the same way as FK506 also was free of effect on enzyme levels in the rat pancreas, but the exocrine secretion of the enzyme from the pancreatic lobules on stimulation with carbachol was impaired. It is concluded that FK506 does not affect pancreatic exocrine function in rats.

Amylases↗

PubMed1992

Variable cross-reactivity of Pseudomonas aeruginosa lipopolysaccharide-code-specific monoclonal antibodies and its possible relationship with serotype.

The core region of Pseudomonas aeruginosa lipopolysaccharide (LPS) was analysed by four LPS-core-specific human monoclonal antibodies (mAbs; FK-2E7, MH-4H7, OM-1D6 and NM-3G8). Reactivity of these mAbs to about 180 P. aeruginosa strains was tested. FK-2E7 bound to strains of Homma serotype E and I at a frequency of about 90%, to strains of serotype M at about 50%, and to strains of serotype A and G at about 30%. MH-4H7 bound to P. aeruginosa strains of serotype A, F, G, H, K and M at a high frequency (45-87%), but did not bind to any strains of serotype B, C, E and I. OM-1D6 and NM-3G8 bound to P. aeruginosa strains in a nearly serotype-specific manner. OM-1D6 reacted with all strains of serotype G so far tested, and a few strains of serotype M. Furthermore, L-rhamnose in the LPS core of serotype G was an immunodominant sugar recognized by OM-1D6 as an epitope. NM-3G8 bound to only a few strains of serotype B and M. The variable reactivity of these mAbs suggests that antigenic heterogeneity of the LPS core is somewhat related with (O-polysaccharide-based) serotype. Among these mAbs, MH-4H7 and OM-1D6 showed a high level of protective activity against P. aeruginosa in an experimental infection model using normal mice. In vivo protective activity was shown to be closely related to in vitro binding activity to whole cells as determined by agglutination and flow cytometry, but not ELISA.

Agglutination Tests↗

PubMed1992

Temperature-sensitive immunoglobulin A-binding and dimerization of C-terminus-impaired protein Arp4 produced in Escherichia coli.

A gene for protein Arp4, an IgA receptor protein derived from Streptococcus pyogenes AP4, was expressed in Escherichia coli. The product was demonstrated to be accumulated in a periplasmic space as a polypeptide with an apparent molecular weight of 40 kDa with the deleted C-terminal membrane anchor portion of protein Arp4. This 40-kDa peptide of the C-terminus-impaired recombinant protein Arp4 produced in E. coli, designated ir-protein Arp4, was purified from a periplasmic fraction of transformants and its IgA-binding activity was analyzed. The IgA binding of ir-protein Arp4 was temperature-sensitive, that is, ir-protein Arp4 bound IgA at 4 and 25 C, but did not at 37 C. In addition, the dimerization of ir-protein Arp4 was also temperature-sensitive in parallel with temperature-dependent binding activity, suggesting that the dimerization of ir-protein Arp4 may be required for its active binding to IgA. In contrast, ir-protein Arp4 immobilized on Sepharose 4B did bind to IgA even at 37 C as well as 4 and 25 C. The immobilized ir-protein Arp4 might acquire the temperature-resistant IgA binding activity in part through the formation of a stable dimerized ir-protein Arp4 on the solid support.

Bacterial Proteins↗

PubMed1992

Effects of a human antiflagellar monoclonal antibody in combination with antibiotics on Pseudomonas aeruginosa infection.

The in vivo activity of human immunoglobulin M monoclonal antibody IN-2A8, which is specific for flagellum type b of Pseudomonas aeruginosa, was evaluated in comparison to anti-O antigen (serotype B) MAb KO-2F2 and in combination with antibiotics. IN-2A8 showed stronger activity than KO-2F2 against subcutaneous infection in burned mice, while it was much less active against intraperitoneal infection in normal mice. In a burn infection model, IN-2A8 inhibited the increase of bacteria in skin lesions weakly and that in blood significantly, suggesting that it strongly suppressed bacterial spread to blood. The activity of IN-2A8 in combination with 10 antipseudomonal antibiotics against intraperitoneal infection was examined. Clear additive effect was observed with a combination of either carbapenem or aminoglycoside antibiotics in terms of mouse survival. The administration of an antibiotic, imipenem-cilastatin, simultaneously with or before that of IN-2A8 gave a combined effect, but the reverse order did not. The combination of IN-2A8 with imipenem-cilastatin decreased numbers of viable bacteria in the peritoneal cavity and blood and kept them low for a longer time than did either treatment alone. These results suggest that an antiflagellar monoclonal antibody would be effective against systemic infection in combination with some kinds of antibiotics.

Animals↗

PubMed1992

Binding of monoclonal antibody specific for domain Ia/II of Pseudomonas aeruginosa exotoxin A at pH 4 strongly neutralizes exotoxin A-induced cytotoxicity in cell culture and in vivo.

Mouse monoclonal antibodies (MAbs) against Pseudomonas aeruginosa exotoxin A (Ex-A) were established, and 4 of 20 MAbs were extensively studied for analysis of the structure-function relationship of Ex-A. IN vivo experiments demonstrated that MAb Ex-3C7 protected mice either injected with Ex-A or infected with Ex-A-producing P. aeruginosa from death caused by Ex-A at the highest rate, followed by MAbs Ex-4F2 and Ex-8H5, in that order. MAb Ex-2A10 failed to rescue the mice. MAb Ex-3C7 (immunoglobulin G1 [IgG1]) inhibited incorporation of Ex-A into target cells and strongly neutralized cytotoxicity in cell culture but did not inhibit an enzymatic activity of Ex-A, ADP-ribosyltransferase, at all. The MAb also bound Ex-A, even at a low pH of 4, and recognized amino acid residues 241 to 297 (domain Ia/II), suggesting that MAb Ex-3C7 can interfere with the conformational change and/or processing of Ex-A by keeping a complex of Ex-A and antibody stable at low pH in the phagolysosome. MAb Ex-4F2 (IgG1), which recognizes residues 550 to 590 (domain III), strongly inhibited Ex-A incorporation and neutralized cytotoxicity in cell culture but only weakly inhibited ADP-ribosyltransferase. MAb Ex-8H5 (IgG1), which recognizes residues 591 to 613 (domain III), also inhibited cytotoxicity in cell culture, but weakly. In contrast to the above three MAbs, MAb Ex-2A10 (IgG2b) greatly inhibited ADP-ribosyltransferase but showed no inhibition of Ex-A incorporation and no neutralizing activity against cell toxicity. A line of evidence indicates that (i) domain Ia/II plays an important role in the pathogenesis of Ex-A and (ii) MAbs that inhibit an intracellular postbinding process, such as conformational change, processing, and translocation of Ex-A in target cells, can display potent inhibitory activity against cytotoxicity in vivo, as well as in cell culture, and would be a good candidate for therapy of pseudomonal infections.

ADP Ribose Transferases↗

PubMed1992

Hepatocellular carcinoma in children with hepatitis B surface antigen.

This study discusses four children of hepatocellular carcinoma (HCC) who were asymptomatic HBsAg carriers or had HBsAg-positive chronic hepatitis for 3 to 11 years before the occurrence of the carcinoma. Three of these four patients were positive for anti-HBe at 3 to 5 years before the diagnosis of hepatocellular carcinoma. Autopsy findings disclosed liver cirrhosis in all the four patients. To the best of our knowledge few reports have documented children in HBsAg carrier status or with HBsAg-positive hepatitis prior to the development of hepatocellular carcinoma. It is emphasized that HBsAg-positive children, with or without detectable hepatic lesions in routine examinations, have a possibility of developing HCC, and should be carefully monitored for long periods.

Adolescent↗

PubMed1992

Two fatal cases of hepatitis B virus carriers after corticosteroid therapy for bronchial asthma.

We report two hepatitis B virus (HBV) carriers who had liver failure after withdrawal of corticosteroids (steroids) administered for treatment of serious asthmatic attacks. Liver functions deteriorated 1 to 2 wk after withdrawal of the steroid therapy and liver failure occurred. Steroid readministration and intensive therapy for liver failure did not prevent death. An excessive immune response provoked by steroid withdrawal and decreased reserve capacity due to underlying chronic liver disease were thought to be factors in the liver failure. Caution must be exercised in the administration of steroids to patients with underlying chronic HBV infection to prevent exacerbation of hepatitis. Prompt readministration of steroids is indicated if evidence of liver failure develops.

Aged↗

PubMed1992

[Intra-arterial infusion chemotherapy for hepatocellular carcinoma using an implantable drug delivery system].

Intra-arterial chemotherapy and chemoembolization using implantable drug delivery system were performed in sixty-one cases of unresectable hepatocellular carcinoma (HCC). The following results were obtained. (1) The follow-up period was 253 days, and the administrations numbered 13.9 times on average. (2) Response rate was 31.1%. (3) AFP decreased in 80% cases, and PIVKA-II in 83.3% cases. (4) Tumor thrombus in the portal vein disappeared in 4 of 40 cases(10%). (5) Free-CDDP continued for 60 minutes after injection of cisplatin-phosphatidyl-choline-Lipiodol (CPL), and the response rate was 47%. (6) The survival rates were 56% in one year, 25% in two years, and 20% for three years. These results were significantly higher than those of one shot therapy. It is suggested that good therapeutic effects can be obtained by the implantable drug delivery system, and CPL was a useful anticancer agent for the therapy.

Biomarkers↗

PubMed1992

Variation of pharmacokinetics after oral administration of slow-release metoprolol tablets and pharmacogenetic considerations.

The maximum plasma concentrations (Cmax) after oral administration of 120 mg tablets of slow-release metoprolol (CAS 37350-58-6) to 75 Japanese healthy male volunteers and 15 arrhythmic patients were measured. Extensive and poor metabolizers after oral administrations of slow-release metoprolol tablets were classified by means of the frequency distribution of Cmax values. In addition, the frequency distribution of Cmax values after oral administration of slow-release metoprolol 120 mg tablets was compared with that of conventional metoprolol 40 mg tablets. 1. Mean +/- S.E. values of Cmax, tmax and AUC0-24 after oral administration of slow-release metoprolol tablets to 75 healthy male volunteers and 15 arrhythmic patients were 95.3 +/- 6.6 ng/ml, 4.4 +/- 0.2 h and 1000.4 +/- 70.9 ng.h/ml, respectively. 2. The number of poor metoprolol metabolizers after the oral administration of slow-release tablets in 75 healthy volunteers and 15 patients was estimated to be 2 subjects (2.2%). 3. The frequency distribution of Cmax values after oral administration of conventional metoprolol tablets was similar to that of slow-release metoprolol tablets. In addition, from the result of this study and that obtained in another study, in which the frequency of poor metoprolol metabolizers in British people has been examined, it is concluded that the frequency of poor metoprolol metabolizers varies between ethnic groups (2.2% in Japanese population and 11.3% in British population.

Administration, Oral↗

PubMed1992

Tissue eosinophilia and eosinophil degranulation in syndromes associated with fibrosis.

Eosinophilia has long been associated with endomyocardial fibrosis, but the involvement of the eosinophilia in fibrosis of other organs is unclear. To investigate this question, the authors tested whether tissue eosinophilia and eosinophil degranulation are present in syndromes associated with fibrosis. The authors used an indirect immunofluorescent technique to localize eosinophil granule major basic protein (MBP) in formalin-fixed, paraffin-embedded tissue specimens from 50 patients. Thirty-four specimens were obtained from patients with inflammatory fibrosis: 12 with idiopathic retroperitoneal fibrosis, seven with sclerosing mediastinitis, four with sclerosing cholangitis, and 11 with pulmonary fibrosis. The remaining 16 specimens were obtained from patients with noninflammatory fibrous proliferations: four with keloids, six with scars, three with Dupuytren's contracture and three with dense stromal fibrosis of the breast. Eosinophil infiltration and/or extracellular MBP deposition were observed in 28 of the 34 specimens (82%) from patients with inflammatory fibrosis, including 11 of the 12 cases of retroperitoneal fibrosis, five of the seven cases of sclerosing mediastinitis, all four cases of sclerosing cholangitis, and 8 of the 11 cases of pulmonary fibrosis. In contrast, eosinophil infiltration and MBP deposition were not observed in specimens from the 16 patients with noninflammatory fibrous proliferation (P less than 0.001). These results indicate that eosinophil infiltration and release of a granule protein, namely MBP, commonly occur in inflammatory fibrotic lesions.

Adult↗

PubMed1991

The carboxyl terminal amino acid residues of Pseudomonas aeruginosa exotoxin A involved in cell toxicity and pathogenesis, characterized by a neutralizing human monoclonal antibody.

Human monoclonal antibody HI-1A4 (IgG3, lambda) neutralized a toxicity caused by pseudomonal exotoxin A (Ex-A) in cell culture and in vivo, and was effective in experimental Pseudomonas aeruginosa infections in mice. HI-1A4 inhibited an Ex-A catalyzed ADP-ribosylation of elongation factor 2 but did not inhibit an incorporation of toxin into a target cell at all. One molecule of HI-1A4 neutralized at least 2 molecules of Ex-A. HI-1A4 retained its binding activity at pH 4.0. The epitope region for HI-1A4 was demonstrated to be a carboxyl terminal end of amino acid residues 591-613 of Ex-A. HI-1A4 might bind to Ex-A carboxyl terminal region outside a target cell, be incorporated into cells as a complex with Ex-A, and inhibit the intracellular function in which the carboxyl terminal part of Ex-A was involved, resulting in the interruption of intoxication of Ex-A.

3T3 Cells↗

PubMed1991

Production and characterization of human monoclonal antibody recognizing the N-terminal residues of Pseudomonas aeruginosa exotoxin A.

Human cell lines producing monoclonal antibodies (MAbs) against Pseudomonas aeruginosa exotoxin A were established by EBV transformation followed by cell fusion. Monoclonal antibody FK-001, IgM (mu, kappa), was demonstrated to be specifically reactive with exotoxin A in ELISA and immunoblotting, by recognizing N-terminal 16 amino acid residues of exotoxin A as an epitope. This epitope region belongs to domain I which is required for the binding of exotoxin A to the receptor on target cells. FK-001 showed a partial neutralizing activity for cell toxicity caused by exotoxin A and appeared to be effective against exotoxin A-producing P. aeruginosa infection in mice. A line of evidence suggests that monoclonal antibody FK-001 neutralizes exotoxin A-induced cell toxicity by the interference of accessibility and/or binding of exotoxin A to animal cell receptors.

ADP Ribose Transferases↗