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Biomedical subjects

K Furihata

Publications and source records attributed to K Furihata.

At least 127 records · Page 7Linked to original sources
PubMed1993

[Studies on the fragments of FDP in 3 non-DIC patients with increased FDP levels in the sera].

We previously studied fibrinolysis and fibrinogenolysis by analyzing fragments of fibrin/fibrinogen degradation products (FDP) employing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. In this report, we characterized the fragments of FDP in three patients with increased serum FDP, that were caused by various diseases. In the patient suffering from tuberculous constrictive pericarditis (case 1), the most part of the FDP fragments were DD and D. In the patient suffering from infection in addition to liver cirrhosis (case 2), the most part of the FDP fragments were high molecular weight (HMW) and D. In case 1 and 2, serum FDP levels were increased in parallel with the elevations of CRP levels. Although DD and HMW fragments were remarkably increased in case 1 and 2 with our immunoblotting analysis, DD levels assayed with LPIA system were much lower than FDP levels. The reason this discrepancy was explained by the observation that affinities of the monoclonal antibody used in LPIA system with DD and HMW fragment were markedly lower than that to DD-E fragment. In the patient suffering from deep vein thrombosis probably caused by steroid therapy of nephrotic syndrome (case 3), the most part of detected FDP fragments were DD and HMW in the period when APTT was shorter than normal, whereas D was mainly observed in the period when APTT was normal. In case 3, FDP and DD levels were increased in parallel with the shortening of APTT. In these non-DIC patients, increased serum FDP levels were induced by the presence of ascites and/or pleural effusion plus infection.(ABSTRACT TRUNCATED AT 250 WORDS)

C-Reactive Protein↗
PubMed1993

[Studies on the fragments of FDP in 3 patients with DIC associated with acute promyelocytic leukemia].

We previously reported a study on fibrinolysis and fibrinogenolysis that analyzed fragments of fibrin/fibrinogen degradation products (FDP) using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. In this report, we characterized the fragments of FDP in three patients with disseminated intravascular coagulation (DIC) associating with acute promyelocytic leukemia (APL). D, Y, DD, DY/X and high molecular weight fragments were observed in sera of all the patients obtained at the onset of APL. These results showed that various degrees of fibrinogenolysis, concomitant with fibrinolysis, was occurring in APL patients presenting DIC. However, changes in the patterns of the FDP fragments during anticoagulation therapy were apparently different among three patients. Namely, fibrinogenolysis was dominant in case 1, while fibrinolysis was dominant in case 2. Interestingly, fibrinogenolysis and fibrinolysis were almost equivalent from the onset to the end of DIC in case 3. In case 3, FDP and FDP-D dimer were remarkably elevated about two months before the onset of APL, although their elevation was not complicated with DIC but with bone marrow necrosis. At that time, serum LDH levels and plasma polymorphonuclear elastase (PMN-Ela) were increased presumably due to the release of these enzymes from necrotic bone marrow, and the levels of CRP and plasma fibrinogen were increased probably due to an infectious complication. In non-DIC period of case 3, FDP and FDP-D dimer were spontaneously decreased without reduction of PMN-Ela levels, after three weeks of chemotherapy for microbial agents. Taken together, characteristics of FDP fragments were unique to each case of APL-DIC, probably because many factors differently affected the degradation of fibrin and/or fibrinogen.

Adolescent↗
PubMed1992

Identification and characterization of apolipoprotein(AII-E2-AII) complex in human plasma lipoprotein.

A new apolipoprotein complex designated as the apo(AII-E2-AII) complex was identified in the lipoprotein fractions of human plasma with apoE phenotypes containing apoE2 (E4/E2, E3/E2, and E2/E2). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by an immunoblotting assay using anti-apoE or anti-apoAII antibodies, established that the apo(AII-E2-AII) complex, with a molecular weight of 58,000, was identical to the complex consisting of apoE and apoAII, and that it also dissociated following reduction with beta-mercaptoethanol. This new complex was also demonstrated to be distinct from the apo(E-AII) complex and apoE monomer by isoelectric focusing, in the samples that were not treated with beta-mercaptoethanol. In apoE phenotype E3/E2, the apo(AII-E2-AII) complex was primarily included in the high-density lipoprotein (HDL, 1.063 < d < 1.21 g/ml) fraction, but was also observed in a small quantity in the very-low-density lipoprotein (VLDL, d < 1.006 g/ml) fraction. For further characterization, the apo(AII-E2-AII) complex was isolated by preparative SDS-PAGE, and no contamination of apo(E-AII) complex and apoE monomer was detected by immunoblotting assay using an anti-apoE antibody. It was confirmed by an enzyme-linked immunosorbent assay (ELISA) system that a molecular ratio between apoAII monomer and apoE in the isolated apo(AII-E2-AII) complex was approx. 2, when the apo(E-AII) complex was used as a standard with the ratio of 1:1. It indicates that the apo(AII-E2-AII) complex is formed from two molecules of apoAII monomer and one molecule of apoE.(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoprotein A-II↗
PubMed1992

Genetic and structural characterization of an amino acid dimorphism in glycoprotein Ib alpha involved in platelet transfusion refractoriness.

The platelet-specific alloantigen, Siba, located within the alpha-subunit of the glycoprotein (GP) Ib-IX membrane receptor, has been found to be involved in the pathogenesis of platelet transfusion refractoriness. We have identified the existence of a naturally occurring threonine/methionine dimorphism at position 145 of the GPIb alpha sequence, and determined that the Siba antigen corresponds to the molecule containing methionine145. The diallelic codons can be detected by restriction enzyme analysis of amplified genomic DNA fragments from the GPIb alpha gene. Evaluation of 61 healthy blood donors showed that the allele frequencies are 89% and 11% for the threonine145 and methionine145 codons, respectively. A positive correlation exists between platelet reactivity with the anti-Siba antibody and the presence of a methionine145-encoding allele. Moreover, recombinant expression of two soluble GPIb alpha fragments differing only at residue 145, provided definitive evidence that the human anti-Siba antibody reacts only with the molecule containing methionine145. These results explain the structural basis of the Siba human alloantigen system and define screening methodologies useful in transfusion medicine to match donor and recipient platelets accordingly.

Amino Acids↗
PubMed1992

An amino acid polymorphism within the RGD binding domain of platelet membrane glycoprotein IIIa is responsible for the formation of the Pena/Penb alloantigen system.

The human Pena/Penb alloantigen system represents a naturally occurring polymorphism of human platelet membrane glycoprotein (GP) IIIa, and has previously been implicated in the onset of two important clinical syndromes, neonatal alloimmune thrombocytopenic purpura and posttransfusion purpura. To investigate the molecular basis of the polymorphism underlying the Pen alloantigen system, we used the polymerase chain reaction to amplify platelet-derived GPIIIa mRNA transcripts. DNA sequence analysis of amplified GPIIIa cDNAs from nucleotides 161 to 1341 (encompassing amino acid residues 22-414) revealed a G526<==>A526 polymorphism that segregated precisely with Pen phenotype in twelve other individuals examined. This nucleotide substitution results in an Arg (CGA) to Gln (CAA) polymorphism at amino acid 143 of GPIIIa. Interestingly, this polymorphic residue is located within the putative RGD binding site (residues 109-171) of GPIIIa. Platelet aggregation patterns of a Penb/b individual, however, were nearly normal in response to all physiological agonists tested, indicating that this polymorphism does not grossly affect integrin function. Short synthetic peptides encompassing residue 143 were unable to mimic either the Pena or Penb antigenic determinants, suggesting that the Pen epitopes are dependent upon proper folding of the polypeptide chain. Finally, we constructed allele-specific recombinant forms of GPIIIa that differed only at amino acid residues 143. Whereas anti-Pena alloantibodies were able to recognize the Arg143 recombinant form of GPIIIa, anti-Penb antibodies were not. Conversely, anti-Penb alloantibodies were reactive only with the Gln143 isoform of the GPIIIa molecule. It thus appears that amino acid 143 of GPIIIa is not only associated with Pen phenotype, but specifically controls the formation and expression of the Pen alloantigenic determinants.

Amino Acid Sequence↗
PubMed1992

Studies on viridenomycin, a novel 24-membered macrocyclic polyene lactam antibiotic.

A new antitumor antibiotic, designated AL081, was obtained from the culture filtrate of an actinomycete identified as Streptomyces gannmycicus, and found to be identical with viridenomycin by direct comparison. The structure of the antibiotic was determined by NMR spectral analysis including a variety of two-dimensional techniques to be a novel 24-membered macrocyclic polyene lactam. Viridenomycin prolonged the survival periods of mice bearing P388 leukemia and B16 melanoma cells.

Animals↗
PubMed1992

New polyenic antibiotics active against gram-positive and gram-negative bacteria. IV. Structural elucidation of enacyloxin IIa.

The chemical structure of a unique polyenic antibiotic enacyloxin IIa (former name: fr. 2) produced by Frateuria (formerly Gluconobacter) sp. W-315 has been determined by extensive spectroscopic studies, in particular by NMR spectral analysis. It has a novel non-lactonic structure involving 3,4-dihydroxycyclohexanecarboxylic acid with a chlorine-containing polyenic and polyhydroxy acyl side chain attached as an ester to the 3-hydroxyl substituent of the acid.

Acetobacteraceae↗
PubMed1992

[Studies on the fragments of FDP in 4 patients with DIC].

We previously studied fibrinolysis and fibrinogenolysis by analyzing fragments of fibrin/fibrinogen degradation products (FDP) employing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. In this report, we characterized the fragments of FDP in four patients with disseminated intravascular coagulation (DIC), that were caused by various diseases. In the patients suffering from acute lymphoblastic leukemia (case 1) and acute suppurative cholangitis (case 3), DD and DY/X fragments resulting from fibrinolysis accounted for the most part of the FDP fragments. In case 3, D fragments resulting from fibrinogenolysis were also observed to much less extent. In a DIC associated with acute myeloblastic leukemia (case 2), both fibrinolysis and fibrinogenolysis were increased and resulted in high levels of D, Y and DY/X fragments, concomitant with moderate levels of DD and high molecular weight (HMW) fragments in the patient's sera. The increased fibrinogenolysis in this case was attributed to accelerated activation of plasmin. In a DIC patient of case 4, who underwent an operation due to hepatocellular carcinoma, marked increase in DY/X and HMW fragments and slight increase in DD fragment were observed on the day of operation. Hyperfibrinolysis documented in case 4 was explained by both increased production of thrombin and moderately accelerated activation of plasmin. Both qualitative and quantitative changes in the fragments of FDP during the courses of treatment in two cases of DIC were also noted. In summary, each underlying disease expresses characteristic pattern of FDP fragments in DIC.

Adolescent↗
PubMed1992

[Differentiation of fibrinolysis and fibrinogenolysis by analysis of FDP fragments].

We previously analysed the fragments of fibrin/fibrinogen degradation products (FDP) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) combined with immunoblotting. In this report, we studied the semi-quantitative analysis of fibrinolysis (degradation of cross-linked fibrin) and fibrinogenolysis (degradation of fibrinogen and/or unstable fibrin) of patients' samples by our method. In vitro study of FDP made it clear that an appearance of D fragment confirmed fibrinogenolysis and an appearance of DD fragment and/or high molecular weight fragments which have higher molecular weight than DY or X fragment confirmed fibrinolysis. In addition, a study with mixtures of various concentrations of fibrin degradation products (FbDP) and fibrinogen degradation products (FgDP) demonstrated a dose dependent intensity of band by immunoblot method. These results show that our method is favorable for the semi-quantitative analysis of fibrinolysis and fibrinogenolysis. We applied the method to 6 samples from patients with disseminated intravascular coagulation (DIC). Consequently, fibrinogenolysis was observed in all of 6 samples, in which fibrinogenolysis was more enhanced than fibrinolysis in one sample, and an equivalent degree of fibrinolysis and fibrinogenolysis were observed in 3 of 6 samples. Although our method was probably devoid of the ability to distinguish FgDP from degradation products of unstable fibrin, these findings indicate that fibrinogenolysis is, at any rate, enhanced in the majority of patients with DIC, besides fibrinolysis.

Electrophoresis, Polyacrylamide Gel↗
PubMed1992

[Efficacy of leukocyte-depleted platelet concentrates for prevention of HLA-alloimmunization in patients with frequent platelet transfusions: a prospective multi-institutional study using a polyester platelet filter].

A prospective multi-institutional study was conducted to assess the efficacy of leukocyte-depleted platelet concentrates, prepared by a method using a newly developed polyester filter, in the prevention of HLA-alloimmunization in patients with hematological disorders. Patients who were expected frequent platelet transfusions, were assigned into two groups, receiving either standard platelet concentrates (control group) or leukocyte-depleted platelet concentrates prepared through a polyester platelet filter, Sepacell-PL (filtered group). All patients received leukocyte-depleted red cell products. Of III patients enrolled, 72 were evaluable, 23 in the control and 49 in the filtered group. Both groups were comparable according to age, sex ratio, underlying disorders, previous exposure to alloantigens by transfusion and/or pregnancy. There was no statistically significant difference in the number and duration of transfusion in the two groups. There were significant differences in HLA-alloimmunization rate (9 cases out of 23, 39% in the control group versus 4 cases out of 49, 8% in the filtered group; p less than 0.01) and refractoriness to platelet transfusion from random donors (6 cases out of 23, 26% in the control group versus 2 cases out of 49, 4% in the filtered group; p less than 0.05). These results indicated that leukocyte-depleted platelet concentrates prepared through the polyester platelet filter are beneficial to reduce HLA-alloimmunization in patients with frequent platelet transfusions.

Adolescent↗
PubMed1991

Human platelet-specific antigen, Siba, is associated with the molecular weight polymorphism of glycoprotein Ib alpha.

Platelet-specific antigen Sib(a) has been highly implicated in the pathogenesis of refractoriness to human leukocyte antigen (HLA)-matched platelet transfusions in Japan. We provide evidence that the Sib(a) antigen is located on the glycoprotein (GP) Ib alpha and has a close association with the molecular weight (mol wt) polymorphism of GPIb. In modified antigen-capture ELISA (MACE), anti-Sib(a) antibody reacted only with GPIb/IX held by a murine anti-GPIb/IX monoclonal antibody (MoAb). The reactivity of anti-Sib(a) antibody to Sib(a)-positive (Sib(a+)) platelets was abolished after they were treated with Serratia marcescens protease. Platelets from 50 healthy volunteers were semiquantitatively phenotyped for Sib(a) antigen by MACE and divided into three distinct groups: strongly positive, positive, and negative. They were also analyzed by sodium dodeyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and periodic acid-silver staining for mol wt polymorphism of GPIb, phenotyped as A, B, C, or D. Without exception, Sib(a+) platelets showed larger phenotypes (A or B). Removal of sialic acid from Sib(a+) platelets did not reduce the binding of anti-Sib(a). Finally, anti-Sib(a) antibody specifically immunoprecipitated A and B phenotypes of GPIb from Sib(a+) platelets. Thus, Sib(a) antigen evidently is located in the region of glycocalicin that is present only on the A and B phenotypes of GPIb.

Antigens, Human Platelet↗
PubMed1991

Studies on the isotetracenone antibiotics. IV. Hatomarubigins A, B, C and D, new isotetracenone antibiotics effective against multidrug-resistant tumor cells.

A complex of new isotetracenone group antibiotics was isolated from the cultured broth of Streptomyces sp. 2238-SVT4. It consisted of four related compounds, designated hatomarubigins A, B, C and D, whose structures were elucidated by NMR spectral analysis including a variety of 2D techniques. They enhanced the cytotoxicity of colchicine against multidrug-resistant tumor cells.

Anthraquinones↗