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K Fukada

Publications and source records attributed to K Fukada.

14 recordsLinked to original sources
PubMed1992

Development of a supersensitive polymerase chain reaction method for human T lymphotropic virus type II (HTLV-II) and detection of HTLV-II proviral DNA from blood donors in Japan.

A supersensitive polymerase chain reaction procedure was developed to detect human T-lymphotropic virus type II (HTLV-II) proviral genome. Six primer pairs covering the various regions of HTLV-II were compared and selected on the basis of specificity and sensitivity. Among them, one primer pair of the pol region of HTLV-II (II pol) was able to amplify and detect even 0.1 fg of the cloned plasmid HTLV-II DNA (seven copies) by regular ethidium bromide staining on polyacrylamide gel. By using this procedure, we screened 189 HTLV-I seropositive blood donors from Yamaguchi and Fukuoka Red Cross Blood Centers, Japan. There were four positive samples detectable with the HTLV-II-specific pol primer pair, as well as with the HTLV-I tax primer pair. The amplified DNAs of two specimens were cloned and sequenced. The sequences of the HTLV-I tax region from both specimens were identical to that of HTLV-I. On the other hand, those of the HTLV-II pol region were identical to that of HTLV-II, except for one base substitution in a clone from one subject. These results indicate that dual infection of HTLV-I and HTLV-II in the same persons occurs among Japanese blood donors.

Base Sequence↗
PubMed1992

Some chemical properties of the HCl-methanol extract from the puparial cuticle of Drosophila melanogaster.

1. The HCl-methanol (HCl-MeOH) soluble fraction from the puparial cuticle of yellow, black and ebony of D. melanogaster was hydrolyzed in hydrochloric acid and examined for beta-alanine, ketocatechol, and acetic acid. 2. Between beta-alanine and ketocatechol and between beta-alanine and acetic acid, a quantitatively inverse relationship was found, respectively. The former relationship was further confirmed by the feeding experiment of beta-alanine to black. 3. Of total beta-alanine in the HCl-MeOH extract, the proportion of those having free amino group was 74.8 per cent. 4. All these results indicate that the HCl-MeOH soluble fraction of the puparial cuticle may be useful for investigating the cross-link structure of the cuticle.

Acetates↗
PubMed1992

Function-blocking antibodies against cholinergic neuronal differentiation factor.

Cholinergic neuronal differentiation factor, CDF, causes a transition from noradrenergic to cholinergic phenotype in cultured sympathetic neurons. Moreover, its identification with leukemia inhibitory factor has shown that CDF is a multifunctional cytokine. To examine the physiological role of CDF and to further elucidate the as yet unknown effects of CDF on the nervous system, two kinds of function-blocking antibodies were generated. One type, raised against whole native CDF, completely blocks CDF activity, whereas the other type, raised against a synthetic peptide corresponding to the N-terminal amino acid region of CDF, blocks activity partially. All three anti-CDF and two antipeptide polyclonal antibodies tested in this study significantly inhibit CDF function.

Animals↗
PubMed1991

Immunoaffinity purification and dose-response of cholinergic neuronal differentiation factor.

A glycoprotein from heart cell-conditioned medium, cholinergic neuronal differentiation factor (CDF), causes a transition from noradrenergic to cholinergic phenotype in cultured rat sympathetic neurons. Although the transition has been known to occur in a dose-dependent manner and CDF has been purified, the examination of a complete dose-response of neurons to CDF has not been possible because sufficient quantities of pure CDF have not been available. A complete dose-response curve is essential for evaluating the biological response of the neurons, for assessing the physiological role of CDF and for understanding the mechanism of action of CDF. We report here an immunoaffinity-purification procedure for CDF with a 73.1% recovery using antibodies raised against a synthetic peptide homologous with the N-terminal region of CDF. This method produced pure CDF in quantities sufficient for examination of the full dose-response range of the neurons. Our main findings are the following. The dose-responses of acetylcholine and catecholamine metabolisms to CDF are different, although the same molecule affects both transmitters. While the half-maximal concentrations for acetylcholine induction (0.20 nM) and for catecholamine suppression (0.28 nM) are similar, the response of catecholamine metabolism begins slowly and saturates at a CDF concentration (5-20 nM) considerably higher than that of acetylcholine (0.6 nM). This may indicate that CDF affects multiple processes in catecholamine metabolism.

Amino Acid Sequence↗
PubMed1991

Follow-up of asymptomatic HTLV-I carriers among blood donors in Kyushu, Japan.

We examined mortality from adult T-cell leukemia/lymphoma (ATL/ATLL) and other diseases alleged to be associated with human T-lymphotropic virus type I (HTLV-I) among anti-HTLV-I antibody-positive blood donors in Kyushu, Japan. During 1984-87, a total of 3,991 blood donors aged 40 years or over were followed from the date of donation to the date of death or the end of the study. Crude mortality rates from ATL (with 95 percent confidence intervals) were 68 per 100,000 (13-202) for males and 36 per 100,000 (3-132) for females. The rates were underestimated by approximately 50 percent because of self-selection and short observation periods. Neither death rates from other cancers nor death rates from all cancers were elevated.

Adult↗
PubMed1989

The cholinergic neuronal differentiation factor from heart cells is identical to leukemia inhibitory factor.

A protein secreted by cultured rat heart cells can direct the choice of neurotransmitter phenotype made by cultured rat sympathetic neurons. Structural analysis and biological assays demonstrated that this protein is identical to a protein that regulates the growth and differentiation of embryonic stem cells and myeloid cells, and that stimulates bone remodeling and acute-phase protein synthesis in hepatocytes. This protein has been termed D factor, DIA, DIF, DRF, HSFIII, and LIF. Thus, this cytokine, like IL-6 and TGF beta, regulates growth and differentiation in the embryo and in the adult in many tissues, now including the nervous system.

Amino Acid Sequence↗
PubMed1989

Prevention of transmission of human T-lymphotropic virus type 1 (HTLV-1) through transfusion, by donor screening with antibody to the virus. One-year experience.

To prevent the transmission of human T-lymphotropic virus, type 1 (HTLV-1) during blood transfusion, a program was implemented to screen donors for antibodies to the virus, using a newly developed, passive agglutination (PA) method. During the period April 1986 to March 1987, 675 recipients of donor blood in whom the antibody to HTLV-1 was not present before transfusion were followed for at least 50 days after transfusion. One of these 675 seroconverted despite the transfusion of screened blood, but this seroconversion rate (0.15%) represents a marked decrease from the rate of 8.3 percent prevalent before donor screening began. The rate in the Fukuoka area of donors seropositive for anti-HTLV-1 is 5.34 percent, as detected by the PA method and 1.80 percent, as assessed by the indirect immunofluorescence (IF) technique, with PA-positive but IF-negative blood units thus accounting for 3.5 percent (5.34-1.80) of the total blood donated. The seroconversion rate among recipients transfused with blood screened by IF (at Kyushu University Hospital only) from 1981 to 1985 was 0.41 percent, which was not significantly different from the rate of 0.15 percent observed after PA screening. The discrepancy between PA and IF in the rate of seropositivity was due, in part, to the higher sensitivity of PA in detecting anti-HTLV-1. It is proposed that all donor blood in areas where HTLV-1 is endemic be screened by PA before transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Agglutination Tests↗
PubMed1989

The detection of an antibody against IgA allotype A2M 2 and a study of the Am genetic marker among the Han Chinese population.

The serum of a woman was found by the Ouchterlony double-diffusion and the hemagglutination inhibition (HAI) methods to have immunoglobulin A (IgA) deficiency. Further investigation using the hemagglutination (HA) test with red cells coated with IgA myeloma proteins of different specificities showed that the serum agglutinated only IgA2-, A2M-1, and A2M 2-coated cells. The patterns of the HAI test with a reference panel confirmed the presence of two specificities. One was anti-IgA2 and the other was a rare antibody against the allotype A2M 2. The anti-A2M 2 was used for population studies. Testing of the Han Chinese population, including family studies, confirms that A2M.1 and A2M.2 have an autosomal dominant mode of inheritance and are controlled by a codominant allele. The distribution of the two Am genetic markers among the Han Chinese population demonstrated A2M.1 with a gene frequency of 0.553 and A2M.2 with a gene frequency of 0.447 (chi 2 = 0.145, 0.80 greater than p greater than 0.70).

Alleles↗
PubMed1988

The dorsal occult ganglion of the wrist and ultrasonography.

In five cases of suspected occult ganglion on the back of the wrist, an ultrasonographic examination was performed. This revealed a small hypoechogenic area on the dorsal aspect between the scaphoid and the lunate or just dorsal to the lunate. Exploration of this area in three cases confirmed the presence of an occult ganglion. In the other two cases, further aspiration revealed traces of mucinous jelly at the tip of the needle.

Adult↗
PubMed1976

In vitro construction of bacteriophage lambda and plasmid DNA molecules containing DNA fragments from bacteriophage T4.

Restriction endonucleases EcoRI and HindIII generated fragments of T4 cytosine-containing DNA were inserted into bacteriophage vector lambdagtSuIII and plasmid vectors pMB9 and pBR313. Resulting clones were screened for hybridization with 32P labeled T4 tRNA. Recombinant bacteriophages and plasmids were isolated which contained a T4 fragment coding for T4 RNA species 1 and 2 and T4 tRNA Arg. Selected lambda-T4 hybrid bacteriophages were grown to high titer and their DNA analyzed by gel electrophoresis.

Coliphages↗
PubMed1976

Cleavage of T4 species I ribonucleic acid by Escherichia coli ribonuclease III.

T4 Species I RNA, a molecule 140 nucleotides in length with some structural features very much like a tRNA, is specifically cleaved by an enzymatic activity in Escherichia coli extracts to give three segments with 19, 48 and 73 nucleotides. We report the purification and characterization of the E. coli RNase which cleaves two 3' phosphodiester bonds of T4 Species I RNA. This reaction has many properties in common with those catalyzed by E. coli RNase III, although the optimal salt conditions for T4 Species I RNA cleavage differ significantly from those for other RNase III-catalyzed reactions. The reaction is not catalyzed by extracts from an E. coli strain lacking RNase III activity. Furthermore, T4 Species I RNA is cleaved by highly purified E. coli RNase III to yield the same three specific fragments. We conclude that this specific cleavage is due to the action of RNase III, and that the requirement for lower ionic strength may reveal further important properties about this RNA processing enzyme.

Cations, Divalent↗