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K Furihata

Publications and source records attributed to K Furihata.

At least 91 records · Page 5Linked to original sources
PubMed1996

[Comparison of coagulation screening test results in two cases having dysfibrinogen].

We compared coagulation screening test [prothrombin time (PT), activated partial prothrombin time (APTT), fibrinogen level determined by thrombin time method] results in two cases of dysfibrinogenemia which were named Matsumoto I (MI) and II (MII), respectively. Amino acid substitution in MI, gamma 364Asp-->His, and that in MII, gamma 308 Asn-->Lys, were deduced by sequencing analysis of PCR amplified products from each genomic DNA. The ratios of functional fibrinogen levels determined by the thrombin time method to immunological levels determined by the latex photometric assay were markedly decreased in both cases. Thrombin time (TT) in the absence of Ca2+ and fibrin aggregation test were also decreased. It was noted that the above described abnormalities were more prominent in MI than MII. We thought these results reflected the extent of abnormality in fibrin monomer polymerization. Furthermore, the mutation at residue gamma 364Asp in MI is adjacent to the gamma 363Tyr which is within the primary polymerization site of fibrin monomer, whereas the mutation at the residue gamma 308Asn in MII is outside the primary site. Since fibrin monomer polymerization is promoted in lower ionic strength and in higher concentration of Ca2+, the data of PT, APTT, and TT, that were tested in the presence of higher concentration of Ca2+ and fibrin monomer, were similar in MI and MII. In addition, it would be speculated that mutant fibrinogen interferes the function of normal fibrinogen existed in heterozygous dysfibrinogenemia.

Afibrinogenemia↗
PubMed1996

Fibrinogen Matsumoto I: a gamma 364 Asp-->His (GAT-->CAT) substitution associated with defective fibrin polymerization.

Fibrinogen Matsumoto I is a novel hereditary dysfibrinogen identified in a 1-year-old boy with Down's syndrome. Though he showed no apparent bleeding or thrombotic tendency, he had a congenital heart disease. Preoperative coagulation tests of his plasma revealed a prolonged thrombin time and the fibrinogen level determined by the thrombin time method was markedly decreased. Molecular weight of fibrinogen chains showed apparently normal A alpha-, B beta-, and gamma-chains. The rate of fibrinopeptide release was normal, whereas fibrin polymerization was delayed. Fibrinogen gamma-chain gene fragments from the propositus were amplified by polymerase chain reaction then sequenced. The triplet GAT, coding for the amino acid residue gamma 364, was replaced by CAT, resulting in the substitution of Asp-->His. This residue is adjacent to the Tyr-363 that is demonstrated to be the primary site for fibrin polymerization. Our results indicate that the residue gamma 364 Asp is essential for normal polymerization of fibrin monomer.

Asparagine↗
PubMed1996

The largest isoform of platelet membrane glycoprotein Ib alpha is commonly distributed in eastern Asian populations.

Platelet membrane glycoprotein Ib alpha has at least two polymorphisms which affect phenotype. One is the dimorphism at codon 145, and the other is a molecular weight polymorphism due to variable numbers of tandem repeats (TR) in the macroglycopeptide region. These two polymorphisms are in linkage disequilibrium. The frequencies of these polymorphisms differ considerably depending on race, and the largest variant with four TR is almost exclusively present in the Japanese population. We examined the genotypes of HPA-2 and TR polymorphism in three different races from Eastern Asia; the Japanese (n = 103), Korean (n = 101) and Chinese population (n = 177). The gene frequency of HPA-2 differed significantly among these three populations. Among HPA-2b-positive individuals, the A isoform with four TR and B with three TR were present in all three populations and A dominated over B. Individuals homozygous for the A isoform were found in both Japanese and Korean populations. These findings indicate that the largest haplotype is common in the Eastern Asian region.

Antigens, Human Platelet↗
PubMed1995

Clustering of the trp genes in Burkholderia (formerly Pseudomonas) cepacia.

Chromosomal location of trp genes of a strain Burkholderia cepacia (formerly Pseudomonas cepacia) has been determined by transduction using a generalized transducing phage CP75 and by molecular analysis for a cosmid plasmid clone with trp genes isolated from a genomic gene library of the strain. The trp genes were classified into three linkage groups and they all were closely linked on a short chromosomal region probably in the order (trpA, trpB, trpF)-(trpC, trpD)-trpE.

Bacteria↗
PubMed1995

The largest variant of platelet glycoprotein Ib alpha has four tandem repeats of 13 amino acids in the macroglycopeptide region and a genetic linkage with methionine145.

Platelet membrane glycoprotein Ib alpha (GPIb alpha) bears the human platelet alloantigen (HPA)-2 and molecular weight (MW) polymorphisms on sodium dodecyl sulfate-polyacrylamide gels. HPA-2 arises from a threonine/methionine dimorphism at residue 145 of the GPIb alpha sequence, whereas different numbers of tandem repeats of a 39-bp sequence encoding 13-amino acids corresponding to a region between serine399 and threonine411 of the GPIb alpha account for the latter. To identify the genetic basis of the MW polymorphism among Japanese, we counted the tandem repeats in 103 individuals. In addition to the reported three variants with one, two, or three tandem repeats, we identified a new variant with four perfect tandem repeats of the 39-bp sequence that corresponded to the largest phenotype. Phenotypic analysis of the MW polymorphism on 12 individuals including all four phenotypes completely accorded in the genotype. We also determined the genotype of HPA-2 and found that methionine145 was in complete linkage disequilibrium, with the larger variants containing three or four tandem repeats. These results imply a model of evolutionary steps in the gene encoding GPIb alpha.

Alleles↗
PubMed1995

A mutation in the ceruloplasmin gene is associated with systemic hemosiderosis in humans.

We identified a mutation in the ceruloplasmin (Cp) gene in a Japanese family with aceruloplasminemia, some of whose members showed extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus. A post-mortem study of the proband revealed excessive iron deposition mainly in the brain, liver and pancreas. The G to A transition at the splice acceptor site introduces a premature termination codon at the amino acid position 991 by defective splicing, thereby truncating the carboxyl terminus of Cp in affected individuals. We conclude that the mutation in the Cp gene is associated with systemic hemosiderosis in humans.

Alternative Splicing↗
PubMed1995

Construction of a combined NotI/SmaI physical and genetic map of Moraxella (Branhamella) catarrhalis strain ATCC25238.

Using pulsed field gel electrophoresis (PFGE) and Southern hybridization techniques, a physical map of Moraxella catarrhalis strain ATCC25238 was constructed to provide basic genetic knowledge of this bacterium that has attracted attention in recent years as a human pathogen. Restriction endonuclease NotI cut the genome into 10 fragments and SmaI into 9, and the molecular size of the genome was estimated to be 1,940 kilobases. Location of the 12 genes participating in the biosynthesis of purine, pyrimidine and nine kinds of amino acids were determined on the circular physical map of the strain.

Amino Acid Sequence↗
PubMed1995

Ribosylation by mycobacterial strains as a new mechanism of rifampin inactivation.

Several fast-growing Mycobacterium strains were found to inactivate rifampin. Two inactivated compounds (RIP-Ma and RIP-Mb) produced by these organisms were different from previously reported derivatives, i.e., phosphorylated or glucosylated derivatives, of the antibiotic. The structures of RIP-Ma and RIP-Mb were determined to be those of 3-formyl-23-[O-(alpha-D-ribofuranosyl)]rifamycin SV and 23-[O-(alpha-D-ribofuranosyl)]rifampin, respectively. To our knowledge, this is the first known example of ribosylation as a mechanism of antibiotic inactivation.

Inactivation, Metabolic↗
PubMed1995

Rotihibins, novel plant growth regulators from Streptomyces graminofaciens.

In the course of screening search for plant growth regulators, a culture filtrate of Streptomyces graminofaciens 3C02 was found to inhibit the growth of lettuce seedlings. The active substances, named rotihibin A (1) and B (2), were revealed to be lipo-peptidal compounds. Rotihibins inhibit growth of various plants at below 1 microgram/ml, but do not show lethal activity even at higher doses.

Molecular Structure↗
PubMed1995

Stachybocins, novel endothelin receptor antagonists, produced by Stachybotrys sp. M6222. II. Structure determination of stachybocins A, B and C.

The structures of stachybocins A, B and C, new endothelin receptor antagonist, were determined by NMR spectral analysis using pulse-field-gradient technique. Stachybocin A consists of two spirobenzofuran units each fused to a substituted decalin, which were connected by a lysine residue. Stachybocins B and C are derivatives of stachybocin A with an additional hydroxy group at the same position in the different decalin unit.

Benzofurans↗
PubMed1995

Trachyspic acid, a new metabolite produced by Talaromyces trachyspermus, that inhibits tumor cell heparanase: taxonomy of the producing strain, fermentation, isolation, structural elucidation, and biological activity.

Trachyspic acid, a new metabolite that inhibited heparanase, was isolated from the culture broth of Talaromyces trachyspermus SANK 12191. Its structure was deduced from NMR spectral analyses and chemical reactions as a tricarboxylic acid derivative containing a spiroketal. The IC50 value of trachyspic acid against heparanase was 36 microM.

Ascomycota↗
PubMed1995

Isolation and structures of an antifungal antibiotic, fusarielin A, and related compounds produced by a Fusarium sp.

A new antifungal antibiotic, fusarielin A, and three related compounds, fusarielins B, C and D, were obtained from a culture of a Fusarium sp. The skeletal structure and the relative stereochemistry of fusarielin A were determined mainly on the basis of its NMR data, and the absolute structure was elucidated by using the exciton chirality method and the modified Mosher method. The structures of the other homologues were determined by comparison of their spectral data with those of fusarielin A.

Animals↗
PubMed1995

[Detection and identification of mycobacteria by PCR-RFLP method].

The frequency of isolation of Mycobacterium tuberculosis has reported to be decreased, however, Mycobacterium species including MOTT (Mycobacteria other than M. tuberculosis complex) still remain to be the important bacteria causing opportunistic infection. Two clinical procedures have long been adopted to date for the detection of acid fast bacteria belonging to the family Mycobacteriaceae. One is the direct microscopic examination of the specimen stained by Ziehl-Neelsen method, which is rapid, but is relatively insensitive and less specific. And another is a time- consuming culturing technique on slants of Ogawa's media, which takes 4 to 8 weeks of incubation. Recently, various methods to detect mycobacterial DNA have been reported. However, they require a complicated and tedious processes. We represent here a simple method for the detection and identification of Mycobacteria (M. tuberculosis, Mycobacterium marinum, Mycobacterium scrofulaceum, Mycobacterium intracellulare, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium chelonae) using PCR-RFLP method for the 65kDa antigen with high sensitivity and specificity. This includes the amplification of Mycobacterial gene encoding a part of the 65kDa antigen. Subsequently, we sequenced the region amplified by PCR from the seven standard bacterial strains. As the results, we found that HaeIII restriction enzyme is suitable for the prompt and easy discrimination among the seven strains examined. These findings led us to conclude that this method is time-saving and possibly applicable for the rapid detection of Mycobacterial species including MOTT from clinical specimens in routine clinical laboratories.

Base Sequence↗
PubMed1995

[Clinical and etiological studies of IgG antibodies to Helicobacter pylori detected by enzyme-linked immunosorbent assay].

Recently, Helicobacter pylori (H. pylori) has been reported that it is involved in the pathogenesis of duodenal ulcer and might be a risk factor for gastric cancer. To diagnose H. pylori infection, detection of serum antibody is much less stressful and more cost effective than gastric biopsy. Using a serological method, We have reported that the prevalence of serum anti-H. pylori IgG was elevated with age among healthy subjects and over 80% among elder people. Thus, it would be essential to investigate the specificity of the ELISA system (PirikaplateG Helicobacter) for the detection of serum anti-H. pylori IgG. Sera from healthy controls (n = 653) and patients (n = 116) with gastritis, gastric ulcer, and/or duodenal ulcer were studied for anti-H. pylori IgG. Cross reactivity of the anti-H. pylori IgG with closely related bacteria was less than 10% (with C. jejuni: 7.4%, C. laridis: 0.2%, E. coli: -2.4%) in the ELISA system. Anti-H. pylori IgG from both normal controls and the patients were equally neutralized with the extract of H. pylori. Of note was that the prevalence of anti-H. pylori IgG among patients was significantly higher than that among normal controls. Referring to the diagnoses by gastric biopsy, the sensitivity and specificity of this ELISA were 88.2% and 74.2%, respectively. We also demonstrated the clinical usefulness of this ELISA by receiver operating characteristic curve (ROC). Interestingly, several healthy subjects positive for serum anti-H. pylori IgG were voluntarily subjected to gastric biopsy, and proved positive for H. pylori infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗