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M Hatakeyama

Publications and source records attributed to M Hatakeyama.

At least 55 records · Page 3Linked to original sources
PubMed1998

HPLC profile analysis of oleanene-glucuronides in several edible beans.

HPLC analysis and yield of oleanene-glucuronide (OG) was done on some commercially available edible beans: seeds of Glycine max, Glycine max cv. Kuromame, Phaseolus vulgaris cv. Torosuku, Phaseolus vulgaris cv. Toramame, Phaseolus vulgaris cv. Taishokintoki, Phaseolus coccineus cv. Ooshirobana, Phaseolus coccineus cv. Murasakihanamame, Vigna unguiculata cv. Chuguro, Vigna angularis cv. Dainagon, Arachis hypogaea, Pisum sativum, and Vicia faba. All the beans listed above have OG, though in varying the amounts. Furthermore the HPLC profiles of beans belonging to the same genus were very similar except for that of the Vigna genus. There was no great difference of the HPLC profiles with respect to the cultivated varieties. The structures of the major OGs in each type of beans were identified as soyasaponins I (1) and V (2), and phaseoside I (3) (Phaseolus vulgaris and P. coccineus); 1 and soyasaponin II (4) (Glycine max); 1 and 2 (Vigna unguiculata); 1 (Pisum sativum, Arachis hypogaea and Vicia faba). In contrast, those in Dainagon (Vigna angularis cv. Dainagon) were identified as azukisaponins II (5) and VI (6).

Carbohydrate Sequence↗
PubMed1998

A novel epitope (pentapeptide) in the human hemoglobin beta chain.

We have cloned 16 monoclonal antibodies by immunizing mice with human hemoglobin for the purpose of analyzing epitopes in human hemoglobin. By using one, SU-115, which is specific for the beta chain, an epitope in the beta chain reacting with this monoclonal antibody was investigated, and a pentapeptide was identified as a novel epitope. After digestion of the beta chain by lysylendopeptidase, the antigenicity of degradation products was examined. An antigenic fragment against SU-115 was found to be a peptide corresponding to residues 96-120 of the beta chain by amino acid analysis of its N-terminal region. Several peptides involved in the region of beta96-120 were synthesized to be examined for their reactivity to SU-115 using dot-blot analysis and a resonant mirror detection method, and a pentapeptide (N108VLVC) was determined as a major sequence of an epitope. By injecting this pentapeptide into a mouse, an antibody reacting human hemoglobin (alpha2beta2) in the same order of strength as SU-115, was obtained. The pentapeptide described in this paper seems to be the minimum size as a major sequence of the actual epitope in human hemoglobin so far reported, and in the primary structure of this region (108-112) there is a difference of three amino acids between human and mouse hemoglobin.

Amino Acid Sequence↗
PubMed1997

Effects of zinc and copper on cadmium uptake by brush border membrane vesicles.

The effects of essential metals, zinc (Zn) and copper (Cu), on cadmium (Cd) uptake were investigated in brush border membrane vesicles (BBMV) isolated from the rat renal cortex and LLC-PK1 cells. BBMV were incubated with Cd in the presence or absence of Zn or Cu, and then washed with a chelating agent, EGTA, to remove Cd bound to the outer surface of BBMV. Co-incubation with Zn or Cu decreased Cd accumulation in these BBMV in a concentration-dependent manner. Kinetic analysis of the initial accumulation of Cd suggested that Cd is taken up into rat BBMV via an unsaturable component and a saturable component (K(m) = 13.8 microM, V(max) = 1.44 nmol/mg protein/min), and co-incubation with Zn significantly increased the K(m) of the saturable component without affecting the V(max), whereas Cu significantly increased the K(m)-value and decreased the V(max)-value. Increasing the osmolarity of the incubation medium slightly decreased Cd accumulation in the absence of Zn or Cu, whereas it did not decrease Cd accumulation in the presence of these metals. These results suggest the possibility that, in addition to passive diffusion, Cd is also taken up from the renal brush border membrane via carrier-mediated mechanisms that are inhibited by Zn competitively and by Cu non-competitively. Furthermore, these results suggest that: (1) Cd binds externally and internally to BBMV, (2) little Cd is transported into the intravesicular space, and (3) both Zn and Cu decrease the binding and transport of Cd.

Animals↗
PubMed1997

Cloning of cDNA for vitellogenin of the parasitoid wasp, Pimpla nipponica (Hymenoptera: Apocrita: Ichneumonidae): vitellogenin primary structure and evolutionary considerations.

The cDNA for vitellogenin (Vg) of the parasitoid wasp Pimpla nipponica (Hymenoptera: Apocrita) was cloned and sequenced. The deduced amino acid sequence with 1807 residues was obtained. The N-terminal 20 amino acids chemically determined for vitellin (Vn) agreed completely with the deduced 20 amino acids that follow the 16 amino acid residues for putative signal peptide. The cDNA clone for the Vg of the turnip sawfly Athalia rosae (Hymenoptera: Symphyta), previously obtained and partially sequenced, was also completely sequenced and the amino acid sequence deduced. Amino acid sequences were compared between these two species and also with known Vg sequences from other insects. Common to all these insects is the presence of two long regions with relatively well-conserved amino acid sequences, one near the N-terminal extending 267-282 residues (including two cysteines at conserved locations), and the other starting at position 450 to 655 and extending 279-283 residues, and of a region at the C-terminal extending some 200 residues (about 250 in Aedes aegypti due to the presence of a serine-rich stretch) with 10 cysteines at conserved locations. A molecular phylogenetic tree was constructed.

Amino Acid Sequence↗
PubMed1996

Selective Isolation of DNA or RNA Using Single-Stranded DNA Affinity Latex Particles.

We developed latex particles with a diameter of about 0.22 µm on which single-stranded (ss) DNA was covalently coupled to select or enrich its complementary DNA or mRNA. DNA was first covalently coupled to the latex particles in the double-stranded (ds) form with both blunt and protruding ends. More than 80% of the dsDNA was coupled through the ssDNA stretch at its protruding end. The presence of NaCl in the immobilization reaction severely inhibited DNA from coupling to the particles. The particles were then treated with alkali or heated to denature the dsDNA and sedimented by a brief centrifugation to yield ssDNA immobilized particles. They allowed the selective and efficient isolation of a desired RNA from total cellular RNA.

Journal Article↗
PubMed1996

Sequential occurrence of hepatocellular carcinoma following Waldenström's macroglobulinemia: the pathogenetic role of chronic liver disease.

We report a case of sequential occurrence of hepatocellular carcinoma (HCC) following Waldenström's macroglobulinemia (WM) in the course of chronic liver disease. The diagnosis of WM was made in a 55-year-old man with a history of alcohol abuse. He developed HCC in the course of WM, and hepatitis C virus (HCV) infection was detected by enzyme-linked immunosorbent assay. Recent reports suggest that persistent HCV infection is related to the pathogenesis of B cell malignancy. Chronic liver disease may be associated with the pathogenesis of the double malignancies in the present case.

Carcinoma, Hepatocellular↗
PubMed1995

IL-2 signaling involves recruitment and activation of multiple protein tyrosine kinases by the IL-2 receptor.

The IL-2 receptor (IL-2R) consists of three subunits, the IL-2R alpha, IL-2R beta, and IL-2R gamma chains, the last of which is also used in the receptors for IL-4, IL-7, IL-9, IL-13, and IL-15. The IL-2-induced proliferative signals emanate from the cytoplasmic domains of IL-2R beta and IL-2R gamma, but the nature and function of the signaling molecules that transmit these signals are not fully understood. Here we summarize our current understanding of the mechanisms by which IL-2R transmit signals by using multiple protein kinases. In fact, at least four protein tyrosine kinases (PTKs) are physically associated with IL-2R: p56lck (and its members), Syk PTK, and the Janus kinases, Jak1 and Jak3. cDNA expression studies revealed that the activation of these PTKs is critical for IL-2-induced proliferative signal transmission. Our findings indicate that a unique property of the IL-2R cytoplasmic domains is to recruit a variety of signaling molecules, which may suggest a mechanism by which these PTKs and other signaling molecules function in concert.

Animals↗
PubMed1995

The role of RB in cell cycle control.

The retinoblastoma protein is an inhibitor of cell cycle progression from the G1 to the S phase of the cell cycle. It acts through its ability to interact with cellular target molecules such as E2F transcription factors. The function of pRB is negatively regulated by a cell-cycle dependent phosphorylation catalyzed by cyclin-dependent kinases in the late G1 cell cycle phase. Recent evidence indicates that this pRB inactivation is a key molecular event leading to the S-phase commitment at the G1 restriction point in the cell cycle. Deregulated inactivation of pRB in G1 phase may be a universal mechanism underlying cellular transformation.

Animals↗
PubMed1995

Acute graft-versus-host disease of the gut.

A 28-year-old man with acute promyelocytic leukemia at first early relapse received HLA-matched allogenic bone marrow transplantation (BMT) at first early relapse. Cyclosporin A and methotrexate were administered at conventional doses as a prophylaxis for graft-versus-host disease (GVHD). He presented with severe bloody diarrhea on day 87 after BMT. Examination of the lower gastrointestinal tract revealed diffuse mucosal change of inflammation. A diagnosis of late onset of acute gut GVHD was made, in the absence of other manifestations such as skin and liver involvement. A further survey is needed to clarify the incidence and the pathogenesis of atypical gut GVHD.

Acute Disease↗
PubMed1994

Collaboration of G1 cyclins in the functional inactivation of the retinoblastoma protein.

The retinoblastoma gene product (pRB) constrains cell proliferation by preventing cell-cycle progression from the G1 to S phase. Its growth-inhibitory effects appear to be reversed by hyperphosphorylation occurring during G1. This process is thought to involve G1 cyclins and cyclin-dependent kinases (cdks). Here we report that the cell cycle-dependent phosphorylation of mammalian pRB is faithfully reproduced when it is expressed in Saccharomyces cerevisiae. As is the case in mammalian cells, this phosphorylation requires an intact oncoprotein-binding domain and is inhibited by a negative growth factor, in this case a mating pheromone. Expression of pRB in cln (-) mutants indicates that specific combinations of endogenous G1 cyclins, Cln3 and either Cln1 or Cln2 are required for pRB hyperphosphorylation in yeast. Moreover, expression of mammalian G1 cyclins in cln (-) yeast cells indicates that the functions of Cln2 and Cln3 in pRB hyperphosphorylation can be complemented by human cyclin E and cyclin D1, respectively. These observations suggest a functional heterogeneity among G1 cyclin-cdk complexes and indicate a need for the involvement of multiple G1 cyclins in promoting pRB hyperphosphorylation and resulting cell-cycle progression.

CDC28 Protein Kinase, S cerevisiae↗
PubMed1994

Cloning of cDNA for vitellogenin of Athalia rosae (Hymenoptera) and characterization of the vitellogenin gene expression.

Athalia rosae (Hymenoptera) was previously shown to have two vitellins (L-Vn and S-Vn) and the two corresponding vitellogenins (L-Vg and S-Vg). A cDNA expression library was constructed from poly(A)+ RNA prepared from adult female fat body cells, and was screened for the vitellogenins by using antisera against the L- and S-Vn, respectively. Examinations of cloned cDNAs show that the vitellogenin gene is transcribed as a single unit, with the 5'-terminal site coding for the S-Vg and the 3'-terminal site for the L-Vg. Nucleotide sequence at the 5'-end suggests the presence of a 16 amino acid-long signal peptide. Deduced amino acid sequence following the signal peptide shows a complete match with up to the 28 N-terminal amino acid sequence determined on S-Vn. The S-L Vg boundary with deduced amino acid sequence matching with 6 N-terminal amino acid sequence determined on L-Vn is also detected. Northern blot hybridization analysis shows that the vitellogenin gene is expressed in the female fat body as a single 6.5 kb mRNA but not in the ovary, and not in the male fat body. Western blot analysis detects a large precursor polypeptide, reacting with the anti-L-Vn and S-Vn antisera, in the adult female fat body.

Amino Acid Sequence↗
PubMed1993

Functional coupling of the src-family protein tyrosine kinases p59fyn and p53/56lyn with the interleukin 2 receptor: implications for redundancy and pleiotropism in cytokine signal transduction.

The binding of interleukin 2 (IL-2) to the IL-2 receptor (IL-2R) induces a rapid increase in tyrosine phosphorylation of cellular proteins. In a previous study, we have shown that p56lck (lck), a src-family protein tyrosine kinase (src-PTK), physically and functionally associates with the IL-2R beta chain (IL-2R beta). To further investigate a role of src-PTKs in IL-2 signaling, we analyzed a mouse pro-B-cell line, in which lck is not expressed detectably. We observed that in this cell line, IL-2 induces activation of at least two src-PTKs, p59fyn (fyn) and p53/56lyn (lyn). Interestingly, stimulation of this cell line with IL-3 also induces activation of src-PTKs. The activation of fyn or lyn seems to be selective for stimulation with IL-2 or IL-3 since stimulation with IL-6 fails to activate them. Furthermore, we provide evidence for the physical association of fyn with IL-2R beta. Taken together with previous results, our current study suggests that different src-PTKs, each of which is expressed in a cell-type-specific manner, can participate in the IL-2 signal transduction.

Animals↗
PubMed1993

Genetics and biology of the sawfly, Athalia rosae (Hymenoptera). Review.

Hymenopteran insects are a unique group of animals in which arrhenotokous reproduction (haploid males develop from unfertilized eggs) is a rule. Males produce sperm through a non-reductional maturation division. A sawfly species, Athalia rosae ruficornis Jakovlev Tenthredinidae, Symphyta, Hymenoptera) has introduced as a new experimental material for studies on genetics and developmental biology. Basic features relating to the potential usefulness of the species in elucidating some to the important genetic and developmental biological problems are described.

Amino Acid Sequence↗
PubMed1993

Incomplete interlobar fissures: bronchovascular analysis with CT.

Thin-section computed tomographic scans of both lungs in 154 patients, including seven cadavers, with lung cancer (n = 37), diffuse (n = 32) or inflammatory (n = 30) lung disease, other proved or suspected disease (n = 23), or healthy lungs (n = 32) were analyzed to determine the frequency of incomplete interlobar fissure (IIF). An IIF was defined as a discontinuous linear shadow that remained in contact with the chest wall. An IIF was found in 128 of 154 right lungs (83.1%) and 77 of 154 left lungs (50.0%). Some bronchovascular structures crossed or passed through two contiguous lobes in the fused area. The most common bronchovascular structure associated with an IIF was a pulmonary vein; this association was found in 87 right lungs (56.5%) and 20 left lungs (13.0%). An IIF was traversed by a pulmonary artery in only seven right lungs and 13 left lungs or by a bronchus in only three lungs. It is concluded that recognition of an IIF might improve understanding of the spread of pulmonary disease.

Bronchi↗
PubMed1992

Purification, cDNA cloning, and expression of UDP-N-acetylglucosamine: beta-D-mannoside beta-1,4N-acetylglucosaminyltransferase III from rat kidney.

UDP-N-acetylglucosamine: beta-D-mannoside beta-1,4N-acetylglucosaminyltransferase III (GnT-III: EC 2.4.1.144) catalyzes the addition of N-acetylglucosamine in beta 1-4 linkage to the beta-linked mannose of the trimannosyl core of N-linked sugar chains. The enzyme has been purified over 153,000-fold in 1.5% yield from a Triton X-100 extract of rat kidney by fractionation procedures utilizing QAE-Sepharose, Cu(2+)-chelating Sepharose, and affinity chromatography on UDP-hexanolamine and substrate-conjugated Sepharose. The purified protein migrates as one major and one minor band with apparent molecular masses of 62 kDa and 52 kDa, respectively. The purified enzyme was digested with trypsin, and the amino acid sequences of four peptides were determined. Oligonucleotide primers were designed according to those amino acid sequences and used in the polymerase chain reaction. Screening for the cDNA for GnT-III was carried out by plaque hybridization using a rat kidney cDNA library (lambda gt10) and a polymerase chain reaction product as the probe. Rat kidney GnT-III has 536 amino acids and three putative N-glycosylation sites. There is no sequence homology to other previously cloned glycosyltransferases, but the enzyme appears to be a type II transmembrane protein like the other glycosyltransferases. The GnT-III activity in transiently transfected COS-1 cells was found to be about 500-3600-fold as compared to that in non- or mock-transfected cells.

Amino Acid Sequence↗
PubMed1992

c-fos gene induction by interleukin 2: identification of the critical cytoplasmic regions within the interleukin 2 receptor beta chain.

Interleukin 2 (IL-2) plays a critical role in the growth and differentiation of lymphoid cells. The IL-2 signal is delivered intracellularly by the IL-2 receptor beta chain (IL-2R beta); however, the mechanism by which the signal reaches the nucleus remains unclear. In this study, we demonstrate the rapid activation of c-fos protooncogene transcription by IL-2 and provide evidence that the serum-responsive element (SRE) within the c-fos promoter is responsible for the activation in a murine pro-B-cell line, BAF-B03, expressing the human IL-2R beta cDNA. Interestingly, the same SRE is also responsible for c-fos gene activation by interleukin 3 or erythropoietin. Further, we show that the activation of c-fos by IL-2 requires defined cytoplasmic regions of IL-2R beta--i.e., the "serine-rich" region, which is known to be essential for growth-signal transduction in BAF-B03 cells, and the "acidic region," which is located more distal to the cell membrane. These results indicate the functional importance of the two distinct regions within the IL-2R beta cytoplasmic domain in IL-2-induced c-fos gene activation and point to a potential role of the acidic region in IL-2 signal transduction that could not be adequately assessed in a previous study.

Animals↗
PubMed1992

[Immuno-hematopoietic cytokine receptor family--its structure and function].

Receptors for immuno-hematopoietic cytokines are multi-chain complexes of membrane proteins. Molecular cloning of these cytokine receptor genes revealed the existence of a here-to-fore unidentified receptor superfamily. They are primarily characterized by a shared extracellular structure that may be involved in the formation of multi-chain receptor complex. Inspite of the lack of any catalytic function, several members of the superfamily are known to act as the transmembrane transducers of cytokine signals. Such molecules may interact physiologically/functionally with multiple intracellular catalytic molecules to generate signals. In this regard, potential involvement of protein tyrosine kinase and protein serine/threonine kinase in the post-receptor signalling has been described. Dysregulated activation of the cytokine receptor gives rise to transformation of immuno-hematopoietic cells.

Animals↗