Showing papers by "Nagoya University published in 1993"
TL;DR: It is reported that PIG-A, which participates in the early step of GPI anchor biosynthesis, is the gene responsible for paroxysmal nocturnal hemoglobinuria.
938 citations
TL;DR: In this paper, a set of kinematic hardening rules for simulating rachetting behavior is presented, where each component has a critical state for its dynamic recovery to be activated fully.
835 citations
TL;DR: In this paper, the authors investigated electrical conduction in sintered oxides based on calcium, strontium or barium zirconate at high temperature and investigated electrochemically.
494 citations
TL;DR: The glycosylphosphatidylinositol (GPI) anchor is a membrane attachment structure of many proteins and occurs in a wide variety of eukaryotes from yeasts to mammals and the structure of the core of the GPI anchor is conserved in protozoa and mammals.
Abstract: The glycosylphosphatidylinositol (GPI) anchor is a membrane attachment structure of many proteins and occurs in a wide variety of eukaryotes from yeasts to mammals The structure of the core of the GPI anchor is conserved in protozoa and mammals and so is its biosynthetic pathway A complementary DNA encoding a human protein termed PIG-A (phosphatidylinositol glycan-class A) was cloned PIG-A was necessary for synthesis of N-acetylglucosaminyl-phosphatidylinositol, the very early intermediate in GPI-anchor biosynthesis
473 citations
TL;DR: Whether these two forms of interstitial pneumonia (UIP and acute lung injury pattern) are variants of one disease or are unrelated and also the effectiveness of corticosteroid therapy on such conditions remain to be determined by further studies.
429 citations
TL;DR: Experiments with non‐myristylation and temperature‐sensitive mutants of RSV and with herbimycin A, a potent inhibitor of tyrosine kinases, suggest that both the suppression of cell adhesion and tyosine phosphorylation of catenins are highly transformation‐specific.
Abstract: Transformation of chick embryonic fibroblasts with Rous sarcoma virus strongly suppresses N-cadherin-mediated cell-cell adhesion, without inhibiting its expression. This suppression is correlated with tyrosine phosphorylation of N-cadherin and catenins, the cadherin-associated proteins, which are known to regulate cadherin function. Experiments with non-myristylation and temperature-sensitive mutants of RSV and with herbimycin A, a potent inhibitor of tyrosine kinases, suggest that both the suppression of cell adhesion and tyrosine phosphorylation of catenins are highly transformation-specific.
425 citations
TL;DR: Evidence is provided that AGE-modified beta 2M is a dominant constituent of the amyloid deposits in hemodialysis-associated amyloidsosis.
Abstract: beta 2-Microglobulin (beta 2M) is a major constituent of amyloid fibrils in hemodialysis-associated amyloidosis, a complication of long-term hemodialysis patients. Amyloid fibril proteins were isolated from connective tissues forming carpal tunnels in hemodialysis patients with carpal tunnel syndrome. Two-dimensional polyacrylamide gel electrophoresis and Western blotting demonstrated that most of the beta 2M forming amyloid fibrils exhibited a more acidic pI value than normal beta 2M. This acidic beta 2M was also found in a small fraction of beta 2M in sera and urine from these patients, whereas heterogeneity was not observed in healthy individuals. We purified acidic and normal beta 2M from the urine of long-term hemodialysis patients and compared their physicochemical and immunochemical properties. Acidic beta 2M, but not normal beta 2M, was brown in color and fluoresced, both of which are characteristics of advanced glycation end products (AGEs) of the Maillard reaction. Immunochemical studies showed that acidic beta 2M reacted with anti-AGE antibody and also with an antibody against an Amadori product, an early product of the Maillard reaction, but normal beta 2M did not react with either antibody. Incubating normal beta 2M with glucose in vitro resulted in a shift to a more acidic pI, generation of fluorescence, and immunoreactivity to the anti-AGE antibody. The beta 2M forming amyloid fibrils also reacted with anti-AGE antibody. These data provided evidence that AGE-modified beta 2M is a dominant constituent of the amyloid deposits in hemodialysis-associated amyloidosis.
423 citations
TL;DR: In this article, the kinematic hardening rules formulated in Part I of this work (i.e., Models I and II) are applied to ratchetting experiments of Modified 9Cr-1Mo steel done by Tanaka et al. as well as to a nonproportional experiment of OFHC copper by Lamba and Sidebottom.
312 citations
TL;DR: The isolation of the yeast MKK1 and MKK2 genes which, when overexpressed, suppress the cell lysis defect of a temperature-sensitive pkc1 mutant are suggested to function in a signal transduction pathway involving the protein kinases encoded by PKC1, BCK1, and MPK1.
Abstract: The PKC1 gene of Saccharomyces cerevisiae encodes a homolog of mammalian protein kinase C that is required for normal growth and division of yeast cells. We report here the isolation of the yeast MKK1 and MKK2 (for mitogen-activated protein [MAP] kinase-kinase) genes which, when overexpressed, suppress the cell lysis defect of a temperature-sensitive pkc1 mutant. The MKK genes encode protein kinases most similar to the STE7 product of S. cerevisiae, the byr1 product of Schizosaccharomyces pombe, and vertebrate MAP kinase-kinases. Deletion of either MKK gene alone did not cause any apparent phenotypic defects, but deletion of both MKK1 and MKK2 resulted in a temperature-sensitive cell lysis defect that was suppressed by osmotic stabilizers. This phenotypic defect is similar to that associated with deletion of the BCK1 gene, which is thought to function in the pathway mediated by PCK1. The BCK1 gene also encodes a predicted protein kinase. Overexpression of MKK1 suppressed the growth defect caused by deletion of BCK1, whereas an activated allele of BCK1 (BCK1-20) did not suppress the defect of the mkk1 mkk2 double disruption. Furthermore, overexpression of MPK1, which encodes a protein kinase closely related to vertebrate MAP kinases, suppressed the defect of the mkk1 mkk2 double mutant. These results suggest that MKK1 and MKK2 function in a signal transduction pathway involving the protein kinases encoded by PKC1, BCK1, and MPK1. Genetic epistasis experiments indicated that the site of action for MKK1 and MKK2 is between BCK1 and MPK1.
312 citations
TL;DR: In this article, a review is given of the differential operator technique in the Ising spin systems and theoretical frameworks of the various models are discussed on the basis of the ISing spin identities.
Abstract: A review is given of the differential operator technique in the Ising spin systems. The theoretical frameworks of the various models are discussed on the basis of the Ising spin identities. These can be applied to examine the magnetic properties in a variety of magnetic materials.
291 citations
TL;DR: In this article, a single crystal of AlN was used as an intermediate layer for the growth of single crystalline GaN films with flat surfaces, which was shown to improve the optical properties of GaN.
TL;DR: In this article, the Ganges Delta and its surrounding region were classified into five sedimentary facies, i.e., the lowest unit of sandy gravels, the lower unit of sand with a few gravels and the middle, upper and uppermost units consisting mainly of sand and silt with occasional peat layers.
TL;DR: In this paper, the spin-dependent structure function g1 p of the proton was measured in deep inelastic scattering of polarized muons off polarized protons, in the kinematic range 0.136±0.011 (stat.)± 0.011(syst.) at Q2 = 10GeV2.
TL;DR: In this article, the same Moller-Plesset perturbation theory was applied to the study of electron correlations in the ground state, singlet and triplet excited states, ionized states and electron attached states of H 2 O. The results compare well with SAC/SAC-CI and full-CI results.
TL;DR: Stretching cellular membranes increased intracellular Ca2+ concentration ([Ca2+]i) in human umbilical endothelial cells cultured on silicon membranes and it is suggested that stretching the membrane primarily induced extracellular Ca1+ entry through stretch-activated (SA) channels followed by Ca2+.
Abstract: Endothelial cells are subjected to shear stresses by blood flow, normal stresses by blood pressure, and stretch by vessel expansion. These forces are known to induce secretions of several vasoactive substances probably via internal calcium mobilization (R. F. Furchgott. Circ. Res. 53: 557-573, 1983; M. J. Peach, A. L. Loeb, H. A. Singer, and J. Saye. Hypertension Dallas 7, Suppl. I: I-94-I-100, 1985). Here we report that stretching cellular membranes increased intracellular Ca2+ concentration ([Ca2+]i) in human umbilical endothelial cells cultured on silicon membranes. Upon application of a stretch pulse (3-s duration), [Ca2+]i increased rapidly and decayed slowly. The following results suggest that this increase arises from Ca2+ entry through stretch-activated (SA) channels: 1) the Ca2+ response disappeared when extracellular Ca2+ was removed; 2) gadolinium (Gd3+), a blocker for cation-selective SA channels, blocked the response but nifedipine did not; and 3) externally applied Mn2+, which is known to permeate mechanosensitive channels but not Ca2+ channels, entered the intracellular space immediately after an application of mechanical stretch. The increase in [Ca2+]i was found to consist of at least two components: an initial fast component and a delayed slower component. Ryanodine inhibited the slow component. It is suggested that stretching the membrane primarily induced extracellular Ca2+ entry through SA channels followed by Ca2+ releases from intracellular Ca2+ stores.
TL;DR: It is suggested that the germ cell specific lamin B3 is involved in the reorganization of nuclear and chromosomal structures during meiotic division.
Abstract: The nuclear lamina is a fundamental component involved in the assembly of the nuclear envelope and higher order chromosomal structures in eukaryotes. In mammals, it is composed of four major lamin proteins, termed lamins A, B1, B2 and C. Here we first report cDNA cloning of a new 53 kDa lamin protein from mouse spermatocytes, termed lamin B3, the expression of which appears restricted to spermatogenic cells. Its gene structure indicates that lamin B3 is generated by differential splicing and alternative polyadenylation from lamin B2. When lamin B3 is introduced into somatic cells in culture, their nuclear morphology is transformed from spherical to hook-shaped. On the basis of the results obtained, we suggest that the germ cell specific lamin B3 is involved in the reorganization of nuclear and chromosomal structures during meiotic division.
Book•
01 Jan 1993TL;DR: In this paper, Kitaoka provides an introduction to quadratic forms that builds from basics up to the most recent results, including lattice theory, Siegel's formula, and some results involving tensor products.
Abstract: The aim of this book is to provide an introduction to quadratic forms that builds from basics up to the most recent results. Professor Kitaoka is well known for his work in this area, and in this book he covers many aspects of the subject, including lattice theory, Siegel's formula, and some results involving tensor products of positive definite quadratic forms. The reader is required to have only a knowledge of algebraic number fields, making this book ideal for graduate students and researchers wishing for an insight into quadratic forms.
TL;DR: Possession of heterogeneous DNA-binding domains and its dynamic change of expression in embryogenesis strongly suggest that delta EF1 acts in multiple ways depending on the cell type and the gene under its regulation.
Abstract: We investigated nuclear factors that bind to delta 1-crystallin enhancer core and regulate lens-specific transcription. A nuclear factor delta EF1, which binds to the essential element of the delta 1-crystallin enhancer core, was molecularly cloned from the chicken by a southwestern method. The protein organization of delta EF1 deduced from the cDNA sequence indicated that it has heterogeneous domains for DNA-binding, two widely separated zinc fingers and a homeodomain, analogous to Drosophila ZFH-1 protein. The C-terminal zinc fingers were found to be responsible for binding to the delta 1-crystallin enhancer core sequence. delta EF1 had proline-rich and acidic domains common to various transcriptional activators. During embryogenesis, delta EF1 expression was observed in the postgastrulation period in mesodermal tissues; initially, in the notochord, followed by somites, nephrotomes and other components. The expression level changed dynamically in a tissue, possibly reflecting the differentiation states of the constituent cells. Besides mesoderm, delta EF1 was expressed in the nervous system and the lens, but other ectodermal tissues and endoderm remained very low in delta EF1 expression. Cotransfection experiments indicated that this factor acts as a repressor of delta 1-crystallin enhancer. Possession of heterogeneous DNA-binding domains and its dynamic change of expression in embryogenesis strongly suggest that delta EF1 acts in multiple ways depending on the cell type and the gene under its regulation.
TL;DR: The filamentous fungus Alternaria alternata produces melanin, a black pigment, from acetate via 1,8-dihydroxynaphthalene through use of a cosmid carrying the hygromycin B phosphotransferase gene, and two genes involved in melanin biosynthesis were found to be designated ALM and BRM2.
Abstract: The filamentous fungus Alternaria alternata produces melanin, a black pigment, from acetate via 1,8-dihydroxynaphthalene. To isolate a fungal gene required for melanin biosynthesis, we transformed an A. alternata Brm1- (light brown) mutant with the DNA of a wild-type strain genomic library constructed by use of a cosmid carrying the hygromycin B phosphotransferase gene. When hygromycin B-resistant transformants were screened for melanin production, 1 of 1,363 transformants appeared to regain melanin production, as judged by black pigmentation of the cultured mycelia. The cosmid, named pMBR1, was recovered by packaging nuclear DNA of the melanin-producing transformant into lambda phage. The gene on pMBR1 that enables the Brm1- mutant to produce melanin was designated BRM1. In addition to the BRM1 gene, pMBR1 was found to carry two more genes involved in melanin biosynthesis. These two genes, designated ALM and BRM2, transformed A. alternata Alm- (albino) and Brm2- (brown) mutants, respectively, to the wild-type phenotype. The three genes are located within a ca. 30-kb genomic region in the order ALM-BRM1-BRM2. Analysis of the gene transcripts indicated approximate sizes of 7.2, 4.0, and 0.9 kb for ALM, BRM1, and BRM2, respectively. The BRM1 and BRM2 transcripts are generated from the same strand, but the ALM transcript is generated from the opposite strand. The three mRNA species accumulate in cultured mycelia of the wild-type strain synchronously with mycelial melanization. The essential roles of the three genes in melanin biosynthesis were confirmed by transformation-mediated gene disruption experiments.
TL;DR: In this article, a new method is proposed to predict the squeezing potential and deformations of tunnels in squeezing rock and applied to actual tunnelling projects, where squeezing problems have been encountered, to check its validity and applicability.
Abstract: The deformational behaviour of tunnels, which underwent large deformations, socalled squeezing, have been recently receiving great attention in the field of rock mechanics and tunnelling. Contrary to rockbursting phenomenon in which the deformation of the medium takes place instantaneously, the deformation of the surrounding rock in squeezing phenomenon takes place slowly and gradually when the resulting stress state following the excavation exceeds the strength of the surrounding medium. Although there are some proposals for the definition of squeezing rocks and prediction of their squeezing potential and deformations of tunnels in literature, it is difficult to say that they are concise and appropriate. In the first half of this paper, the squeezing phenomenon of rock about tunnels and its mechanism and associated factors are clarified by studying carefully observed failures in-situ and laboratory model tests. Then, an extensive survey of tunnels in squeezing rocks in Japan is presented and the results of this survey are summarised. In the second half of the paper, a new method is proposed to predict the squeezing potential and deformations of tunnels in squeezing rock. Then, the method is applied to actual tunnelling projects, where squeezing problems have been encountered, to check its validity and applicability. As a concrete example, an application of the method to predict the squeezing potential and deformations of the rock along a 300 m long section of an actual tunnel was made.
TL;DR: Results indicate that diapause hormone, along with four other neuropeptides, is generated from a common precursor polyprotein that is encoded by a single mRNA transcribed in neurosecretory cells of SG.
Abstract: Peptidergic neurons, which serve as source of various endocrine neuropeptides, were identified in the suboesophageal ganglion (SG) and brain of insects. In the silkworm Bombyx mori, SG is known to secrete two neuropeptides, diapause hormone (DH) responsible for induction of embryonic diapause and pheromone biosynthesis-activating neuropeptide, which share a pentapeptide amide, Phe-Xaa-Pro-Arg-Leu-NH2 (Xaa = Gly or Ser), at the C terminus. We have isolated cDNA clones for DH from the cDNA library of SG by using oligonucleotide probes. The molecular characterization of the cDNA reveals that the mRNA encodes an open reading frame consisting of 192 aa residues in which the 24-aa DH peptide is localized at the N-terminal region just after the signal peptide. A homology search proposed that the cDNA encodes pheromone biosynthesis-activating neuropeptide and three other neuropeptides [alpha-, beta-, and gamma-SG neuropeptide (SGNP)] in the region following DH, all of which are flanked by possible tryptic cleavage sites and share the Phe-Xaa-Pro-Arg-Leu-Gly sequence at the C terminus. Northern hybridization analysis clearly showed that the gene expression was limited to SG. We chemically synthesized alpha-, beta-, and gamma-SGNP and used them to identify components in extracts of SG and to examine biological functions, alpha- and gamma-SGNP were identified in extracts of SG, and the synthetic beta- and gamma-SGNP expressed weak DH activity. These results indicate that DH, along with four other neuropeptides, is generated from a common precursor polyprotein that is encoded by a single mRNA transcribed in neurosecretory cells of SG.
TL;DR: The phenotype of N- myc-deficient mutant embryos indicated requirement of the N-myc function in many instances of tissue interactions in organogenesis and also in cell-autonomous regulation of tissue maturation.
Abstract: The highest expression of the N-myc gene occurs during embryonic organogenesis in the mouse ontogeny, with the peak of expression around embryonic day 9.5. Homozygous N-myc-deficient mice, produced by germline transmission of a disrupted allele in ES cells, developed normally to day 10.5, indicating dispensability of N-myc expression in the earlier period, but later accumulated organogenic abnormalities and died around day 11.5. The most notable abnormalities were found in the limb bud, visceral organs (lung, stomach, liver and heart) and the central/peripheral nervous systems, and were highly correlated with the site of N-myc expression. The limb buds and the lungs excised from N-myc-deficient mutant embryos were placed in culture to allow their development to stages beyond the point of death of the embryos. Analyses indicated that the mutant limbs failed to develop distal structures and the development of bronchi from the trachea was defective in the lungs. The latter defect was largely corrected by addition of fetal calf serum to the culture medium, suggesting that an activity missing in the mutant lung was replenished by a component of the serum. The phenotype of N-myc-deficient mutant embryos indicated requirement of the N-myc function in many instances of tissue interactions in organogenesis and also in cell-autonomous regulation of tissue maturation.
TL;DR: In this paper, a 1.5-order modified Reynolds equation for solving the ultra-thin film gas lubrication problem is derived by using an accurate higher-order slip-flow model.
Abstract: A 1.5-order modified Reynolds equation for solving the ultra-thin film gas lubrication problem is derived by using an accurate higher-order slip-flow model. This model features two key differences from the current second-order slip-flow model. One is the involvement of an accommodation coefficient for momentum. The other is that the coefficient of the second-order slip-flow term is 4/9 times smaller than that for the current model. From the physical consideration of momentum transfer, the accommodation coefficient is found to have no affect on the second-order slip-flow term. Numerical calculations using the 1.5-order modified Reynolds equation are performed
TL;DR: The genetic results demonstrate the connection between raf and the highly conserved protein kinase cascade involving MAP kinase in vivo and reveal its product with striking similarity to the microtubule-associated protein (MAP) kinase activator and yeast PBS2, STE7, and byr1.
TL;DR: The theoretical yield of poly‐D(‐)‐3‐hydroxybutyrate (PHB) has been estimated from the biochemical pathway leading to PHB when a carbohydrate (glucose), a C1 compound, a C2 compound, or a C4 compound is used as a carbon source.
Abstract: The theoretical yield of poly-D(-)-3-hydroxybutyrate (PHB) has been estimated from the biochemical pathway leading to PHB when a carbohydrate (glucose), a C(1) compound (methanol), a C(2) compound (acetic acid), or a C(4) compound (butyric acid) is used as a carbon source. In estimating the yield, recycling (or regeneration) of NADP(+)/ (NADPH + H(+)) and NAD(+) /(NADH + H(+)) have been taken into account. A special emphasis is made on te regeneration of NADPH, which is the coenzyme of acetoacetyl-CoA reductase, one of three key enzymes involved in the biosynthesis of PHB. As a NADPH-regenerating enzyme, glucose-6-phosphate dehydrogenase or isocitrate dehydrogenase is conceived. An equation which predicts the overall yield of PHB when non-PHB residual biomass is actually formed has been derived as a function of both the theoretical yield and PHB content of the dry cell mass. The ratio of the overall yield to the theoretical yield is roughly proportional to the PHB content.
TL;DR: It was demonstrated that H‐NS functions directly as a transcriptional repressor through its direct binding to the promoter region, and the mechanism underlying regulation of the proV promoter in response to the medium osmolarity was discussed.
Abstract: The H-NS protein is a major constituent of the Escherichia coli nucleoid structure and is implicated in the compact organization of the chromosome. Based on recent genetic evidence, this protein appears to influence the transcription of a variety of apparently unlinked genes on the chromosome, although the underlying molecular mechanism is not fully understood. In this study, we carried out a series of in vitro transcription assays including purified H-NS with special reference to the osmotically inducible proV promoter of the proVWX operon (or proU), whose expression is known to be derepressed by lesions of the hns (osmZ) gene. Here, H-NS was revealed to selectively inhibit an early step(s) of proV transcription initiation through its direct binding to the promoter region. It was thus demonstrated that H-NS functions directly as a transcriptional repressor. Under the in vitro conditions used, this in vitro inhibitory effect of H-NS was affected by changes in the superhelical density of template DNAs and more significantly by the concentration of potassium (K+) ions. These results are also discussed with regard to the mechanism underlying regulation of the proV promoter in response to the medium osmolarity.
TL;DR: The possible amount of information transfer between any source and any user via a quantum system is bounded through the quantum entropy function, which shows that infinite information transfer implies infinite entropy.
Abstract: The possible amount of information transfer between any source and any user via a quantum system is bounded through the quantum entropy function. In contrast to the classical case, this shows that infinite information transfer implies infinite entropy. The entropy bound is also applied to obtain the ultimate quantum information transmission capacity of the free electromagnetic field under a power and a bandwidth constraint.
TL;DR: The superiority of Rhodococcus rhodochrous J1 nitrile hydratase was demonstrated in comparison with other acrylamide-producing bacteria and the high stability, high catalytic efficiency and other outstanding features of the J1 enzyme are analysed and discussed.
Abstract: As the third-generation biocatalyst for industrial production of acrylamide, the superiority of Rhodococcus rhodochrous J1 nitrile hydratase was demonstrated in comparison with other acrylamide-producing bacteria. R. rhodochrous J1 enzyme is much more heat stable and more tolerant to a high concentration of acrylonitrile than Pseudomonas chlororaphis B23 and Brevibacterium R312 enzymes. The J1 enzyme is peculiar in its extremely high tolerance to acrylamide. The hydration reaction of acrylonitrile catalysed by J1 cells proceeded even in the presence of 50% (w/v) acrylamide. The tolerance of J1 enzyme to various organic solvents such as n-propanol and isopropanol was prominent. Using R. rhodochrous J1 resting cells, the accumulation reaction was carried out by feeding acrylonitrile to maintain a level of 6%. After 10 h incubation, the accumulation of acrylamide was approximately 65.6% (w/v) at 10°C, 56.7% (w/v) at 15°C, and 56.0 (w/v) at 20°C. The high stability, high catalytic efficiency and other outstanding features of the J1 enzyme are analysed and discussed.
TL;DR: The grouping according to the CUG codon assignments in these yeast species shows a good correlation with physiological classification by the chain lengths of the isoprenoid moiety of ubiquinone and the cell-wall sugar contained in the yeasts.
Abstract: It has been reported that CUG, a universal leucine codon, is read as serine in an asporogenic yeast, Candida cylindracea. The distribution of this non-universal genetic code in various yeast species was studied using an in vitro translation assay system with a synthetic messenger RNA containing CUG codons in-frame. It was found that CUG is used as a serine codon in six out of the fourteen species examined, while it is used for leucine in the remaining eight. The tRNA species responsible for the translation of codon CUG as serine was detected in all the six species in which CUG is translated as serine. The grouping according to the CUG codon assignments in these yeast species shows a good correlation with physiological classification by the chain lengths of the isoprenoid moiety of ubiquinone and the cell-wall sugar contained in the yeasts. The six Candida species examined in which CUG is used as serine belong to one distinct group in Hemiascomycetes.
TL;DR: The structure-activity relationship revealed that either the o -dihydroxy structure in the B ring or certain structures in the A and C rings of the flavonoids are necessary for the protective activities of quercetin and kaempferol.