76
|
Sarkar N, Panigrahi R, Pal A, Biswas A, Singh SP, Kar SK, Bandopadhyay M, Das D, Saha D, Kanda T, Sugiyama M, Chakrabarti S, Banerjee A, Chakravarty R. Expression of microRNA-155 correlates positively with the expression of Toll-like receptor 7 and modulates hepatitis B virus via C/EBP-β in hepatocytes. J Viral Hepat 2015; 22:817-27. [PMID: 25720442 DOI: 10.1111/jvh.12390] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 11/15/2014] [Indexed: 12/11/2022]
Abstract
Effective recognition of viral infection and successive activation of antiviral innate immune responses are vital for host antiviral defence, which largely depends on multiple regulators, including Toll-like receptors (TLRs) and microRNAs. Several early reports suggest that specific TLR-mediated immune responses can control hepatitis B virus (HBV) replication and express differentially with disease outcome. Considering the versatile function of miR-155 in the TLR-mediated innate immune response, we aimed to study the association between miR-155 and TLRs and their subsequent impact on HBV replication using both a HBV-replicating stable cell line (HepG2.2.15) and HBV-infected liver biopsy and serum samples. Our results showed that miR-155 was suppressed during HBV infection and a subsequent positive correlation of miR-155 with TLR7 activation was noted. Further, ectopic expression of miR-155 in vitro reduced HBV load as evidenced from reduced viral DNA, mRNA and subsequently reduced level of secreted viral antigens (HBsAg and HBeAg). Our results further suggested that CCAAT/enhancer-binding protein-β (C/EBP-β), a positive regulator of HBV transcription, was inhibited by miR-155. Taken together, our study established a correlation between miR-155 and TLR7 during HBV infection and also demonstrated in vitro that increased miR-155 level could help to reduce HBV viral load by targeting C/EBP-β.
Collapse
|
77
|
Sugiyama M, Saeki A, Hasebe A, Kamesaki R, Yoshida Y, Kitagawa Y, Suzuki T, Shibata K. Activation of inflammasomes in dendritic cells and macrophages by Mycoplasma salivarium. Mol Oral Microbiol 2015; 31:259-69. [PMID: 26177301 DOI: 10.1111/omi.12117] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2015] [Indexed: 01/27/2023]
Abstract
Interleukin-1β (IL-1β) plays crucial roles in the pathogenesis of periodontal disease. It is produced after the processing of pro-IL-1β by caspase-1, which is activated by the inflammasome-a multiprotein complex comprising nucleotide-binding domain leucine-rich repeat-containing receptor (NLR), the adaptor protein apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), and procaspase-1. Mycoplasma salivarium preferentially inhabits the gingival sulcus and the incidence and number of organisms in the oral cavity increase significantly with the progression of periodontal disease. To initially clarify the association of this organism with periodontal diseases, this study determined whether it induces IL-1β production by innate immune cells such as dendritic cells or macrophages by using Mycoplasma pneumoniae as a positive control. Both live and heat-killed M. salivarium and M. pneumoniae cells induced IL-1β production by XS106 murine dendritic cells as well as pyroptosis. The activities were significantly downregulated by silencing of caspase-1. Bone-marrow-derived macrophage (BMMs) from wild-type and NLR-containing protein 3 (NLRP3)-, ASC-, and caspase-1-deficient mice were examined for IL-1β production in response to these mycoplasmas. Live M. salivarium and M. pneumoniae cells almost completely lost the ability to induce IL-1β production by BMMs from ASC- and caspase-1-deficient mice. Their activities toward BMMs from NLRP3-deficient mice were significantly but not completely attenuated. These results suggest that live M. salivarium and M. pneumoniae cells can activate several types of inflammasomes including the NLRP3 inflammasome. Both M. salivarium and M. pneumoniae cells can activate THP-1 human monocytic cells to induce IL-1β production. Hence, the present finding that M. salivarium induces IL-1β production by dendritic cells and macrophages may suggest the association of this organism with periodontal diseases.
Collapse
|
78
|
Enoki H, Sugiyama M, Kuzuya M. P-355: Relationships among the levels of care needs, dysphagia and malnutrition. Eur Geriatr Med 2015. [DOI: 10.1016/s1878-7649(15)30452-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
79
|
Sugiyama M, Horikoshi N, Suzuki Y, Taguchi H, Kujirai T, Inoue R, Oba Y, Sato N, Martel A, Porcar L, Kurumizaka H. Solution structure of variant H2A.Z.1 nucleosome investigated by small-angle X-ray and neutron scatterings. Biochem Biophys Rep 2015; 4:28-32. [PMID: 29124184 PMCID: PMC5668895 DOI: 10.1016/j.bbrep.2015.08.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/25/2015] [Accepted: 08/25/2015] [Indexed: 11/26/2022] Open
Abstract
Solution structures of nucleosomes containing a human histone variant, H2A.Z.1, were measured by small-angle X-ray and neutron scatterings (SAXS and SANS). SAXS revealed that the outer shape, reflecting the DNA shape, of the H2A.Z.1 nucleosome is almost the same as that of the canonical H2A nucleosome. In contrast, SANS employing a contrast variation technique revealed that the histone octamer of the H2A.Z.1 nucleosome is smaller than that of the canonical nucleosome. The DNA within the H2A.Z.1 nucleosome was more susceptible to micrococcal nuclease than that within the canonical nucleosome. These results suggested that the DNA is loosely wrapped around the histone core in the H2A.Z.1 nucleosome.
Collapse
|
80
|
Takemoto Y, Yamamoto T, Ikuma N, Uchida Y, Suzuki K, Shimono S, Takahashi H, Sato N, Oba Y, Inoue R, Sugiyama M, Tsue H, Kato T, Yamauchi J, Tamura R. Preparation, characterization and magnetic behavior of a spin-labelled physical hydrogel containing a chiral cyclic nitroxide radical unit fixed inside the gelator molecule. SOFT MATTER 2015; 11:5563-5570. [PMID: 26073537 DOI: 10.1039/c5sm01216c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An optically active amphiphilic nitroxide radical compound [(S,S,R)-], which contains a paramagnetic (2S,5S)-2,5-dimethyl-2,5-diphenylpyrrolidine-N-oxyl radical group fixed in the inner position together with a hydrophobic long alkyl chain and a hydrophilic (R)-alanine residue in the opposite terminal positions, was found to serve as a low-molecular-weight gelator in H2O to give rise to a spin-labelled physical hydrogel. Characterization of the hydrogel was performed by microscopic (SEM, TEM and AFM) techniques, XRD and SAXS measurements, and IR, UV and CD spectroscopies. The gel-sol transition temperature was determined by EPR spectral line-width (ΔHpp) analysis. Measurement of the temperature dependence of relative paramagnetic susceptibility (χrel) for the hydrogel and sol phases was achieved by means of the double-integration of VT-EPR spectra.
Collapse
|
81
|
Arimura Y, Kimura H, Oda T, Sato K, Osakabe A, Tachiwana H, Sato Y, Kinugasa Y, Ikura T, Sugiyama M, Sato M, Kurumizaka H. Corrigendum: Structural basis of a nucleosome containing histone H2A.B/H2A.Bbd that transiently associates with reorganized chromatin. Sci Rep 2015; 5:9628. [PMID: 26166249 PMCID: PMC4499879 DOI: 10.1038/srep09628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
82
|
Shigekawa T, Osaki A, Ueda S, Takeuchi H, Hirokawa E, Sugitani I, Sugiyama M, Shimada H, Takahashi T, Saeki T. P310 Local recurrence rates are low in Japanese breast cancer patients after neoadjuvant chemotherapy. Breast 2015. [DOI: 10.1016/s0960-9776(15)70340-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
|
83
|
Osaki A, Shimada H, Sugitani I, Sugiyama M, Hirokawa E, Sano H, Nakamiya N, Ueda S, Shigekawa T, Takeuchi H, Takahashi T, Saeki T. Clinicopathological Characteristics and Outcomes of Breast Cancer Patients with Collagen Disorders. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu327.66] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
84
|
Suzuki K, Ogishima M, Sugiyama M, Inouye Y, Nakamura S, Imamura S. Molecular Cloning and Expression of aStreptomycesSarcosine Oxidase Gene inStreptomyces lividans. Biosci Biotechnol Biochem 2014; 56:432-6. [PMID: 1368326 DOI: 10.1271/bbb.56.432] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A genomic library of Streptomyces sp. KB210-8SY, prepared in the plasmid vector pACYC184, was screened to obtain the gene encoding sarcosine oxidase with probes based on the amino acid sequence of the protein. A plasmid pSOXS13, which was isolated from a clone identified by hybridization with the probes, contained a 8.4-kb insert of Streptomyces DNA. When the 2.0-kb MIuI/EcoRV DNA fragment of pSOXS13 was inserted into the Streptomyces vector pIJ680 and introduced into S. lividans, the transformants produced 100-fold more sarcosine oxidase intracellularly than KB210-8SY. The nucleotides of the 1.7-kb fragment containing the sarcosine oxidase gene were sequenced. An open reading frame encoded a mature sarcosine oxidase consisting of 388 amino acids, with a calculated molecular mass of 42,107 daltons.
Collapse
|
85
|
Hamasaki Y, Watanabe Y, Kotoura S, Fuchu H, Sugiyama M, Hashizume K, Morita H. Paenibacillus maceransPossesses Two Types of 16S rDNA Copies in a Genome with a Length Difference of Twelve Base Pairs. Biosci Biotechnol Biochem 2014; 69:1995-8. [PMID: 16244457 DOI: 10.1271/bbb.69.1995] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Two Paenibacillus macerans strains, JCM 2500T and MCRI 12, exhibited two types of 16S rDNA copies in their genomes, accompanied by a length difference of 12 bp at positions 203 to 214 (Escherichia coli numbering). The long-type sequences were newly identified for P. macerans 16S rDNA, and the copy numbers were different between the two strains. Both types of 16S rRNA were expressed in each strain, and it was predicted that the polymorphism at this position is located in helix H10, based on a comparison with the E. coli 16S rRNA secondary structure model.
Collapse
|
86
|
Rahman N, Sato N, Sugiyama M, Hidaka Y, Okabe H, Hara K. The effect of hot DMSO treatment on the γ-ray-induced grafting of acrylamide onto PET films. Polym J 2014. [DOI: 10.1038/pj.2014.12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
87
|
Hasegawa T, Uchiyama Y, Uemura K, Harada Y, Sugiyama M, Tanaka H. Physical impairment and walking function required for community ambulation in patients with cervical incomplete spinal cord injury. Spinal Cord 2014; 52:396-9. [DOI: 10.1038/sc.2014.18] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 01/28/2014] [Accepted: 02/03/2014] [Indexed: 11/09/2022]
|
88
|
Sugiyama M, Yagi H, Yamaguchi T, Kumoi K, Hirai M, Oba Y, Sato N, Porcar L, Martel A, Kato K. Conformational characterization of a protein complex involving intrinsically disordered protein by small-angle neutron scattering using the inverse contrast matching method: a case study of interaction between α-synuclein and PbaB tetramer as a model chaperone. J Appl Crystallogr 2014. [DOI: 10.1107/s1600576713033475] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Cumulative genomics and proteomics data have now highlighted the presence of intrinsically disordered proteins (IDPs), which are devoid of stable secondary or tertiary structures under physiological conditions. While the flexible nature of IDPs precludes their study by crystallographic methods, IDP interactions with their cognate proteins, during which the IDPs often form their secondary structures, have been characterized by nuclear magnetic resonance (NMR) spectroscopy. In view of this, a complementary small-angle neutron scattering (SANS) technique has been developed for probing IDP conformations in larger protein complexes. As a model interaction system, α-synuclein (αSN) bound to an archaeal homotetrameric chaperone, PbaB, was analyzed. To selectively observe the SANS profile of αSN in the complex, the bacterially produced PbaB was fractionally (75%) deuterated using D2O and deuterated glucose for contrast matching to approximately 100% D2O solvent. By employing 75%-deuterated PbaB, the conformational changes of αSN upon capture by this tetrameric chaperone were successfully observed with minimal background scattering. Together with the present NMR data, the SANS data reveal that the PbaB tetramer grasps the N-terminal segments of αSN, disrupting the residual ordered structure in this region, while leaving the remaining regions flexible within a slightly reduced conformational space.
Collapse
|
89
|
Rahman N, Sato N, Sugiyama M, Hidaka Y, Okabe H, Hara K. Selective Hg(II) adsorption from aqueous solutions of Hg(II) and Pb(II) by hydrolyzed acrylamide-grafted PET films. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2014; 49:798-806. [PMID: 24679087 DOI: 10.1080/10934529.2014.882209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Selective Hg(II) adsorption from aqueous solutions of Hg(II) and Pb(II) using hydrolyzed acrylamide (AAm)-grafted polyethylene terephthalate (PET) films was examined to explore the potential reuse of waste PET materials. Selective recovery of Hg(II) from a mixture of soft acids with similar structure, such as Hg(II) and Pb(II), is important to allow the reuse of recovered Hg(II). An adsorbent for selective Hg(II) adsorption was prepared by γ-ray-induced grafting of AAm onto PET films followed by partial hydrolysis through KOH treatment. The adsorption capacity of the AAm-grafted PET films for Hg(II) ions increased from 15 to 70 mg/g after partial hydrolysis because of the reduction of hydrogen bonding between -CONH2 groups and the corresponding improved access of metal ions to the amide groups. The prepared adsorbent was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The absorbent film showed high selectivity for the adsorption of Hg(II) over Pb(II) throughout the entire initial metal concentration range (100-500 mg/L) and pH range (2.2-5.6) studied. The high selectivity is attributed to the ability of Hg(II) ions to form covalent bonds with the amide groups. The calculated selectivity coefficient for the adsorbent binding Hg(II) over Pb(II) was 19.2 at pH 4.5 with an initial metal concentration of 100 mg/L. Selective Hg(II) adsorption equilibrium data followed the Langmuir model and kinetic data were well fitted by a pseudo-second-order equation. The adsorbed Hg(II) and Pb(II) ions were effectively desorbed from the adsorbent film by acid treatment, and the regenerated film showed no marked loss of adsorption capacity upon reuse for selective Hg(II) adsorption.
Collapse
|
90
|
Arimura Y, Kimura H, Oda T, Sato K, Osakabe A, Tachiwana H, Sato Y, Kinugasa Y, Ikura T, Sugiyama M, Sato M, Kurumizaka H. Structural basis of a nucleosome containing histone H2A.B/H2A.Bbd that transiently associates with reorganized chromatin. Sci Rep 2013; 3:3510. [PMID: 24336483 PMCID: PMC3863819 DOI: 10.1038/srep03510] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 11/29/2013] [Indexed: 01/26/2023] Open
Abstract
Human histone H2A.B (formerly H2A.Bbd), a non-allelic H2A variant, exchanges rapidly as compared to canonical H2A, and preferentially associates with actively transcribed genes. We found that H2A.B transiently accumulated at DNA replication and repair foci in living cells. To explore the biochemical function of H2A.B, we performed nucleosome reconstitution analyses using various lengths of DNA. Two types of H2A.B nucleosomes, octasome and hexasome, were formed with 116, 124, or 130 base pairs (bp) of DNA, and only the octasome was formed with 136 or 146 bp DNA. In contrast, only hexasome formation was observed by canonical H2A with 116 or 124 bp DNA. A small-angle X-ray scattering analysis revealed that the H2A.B octasome is more extended, due to the flexible detachment of the DNA regions at the entry/exit sites from the histone surface. These results suggested that H2A.B rapidly and transiently forms nucleosomes with short DNA segments during chromatin reorganization.
Collapse
|
91
|
Hylton NP, Li XF, Giannini V, Lee KH, Ekins-Daukes NJ, Loo J, Vercruysse D, Van Dorpe P, Sodabanlu H, Sugiyama M, Maier SA. Loss mitigation in plasmonic solar cells: aluminium nanoparticles for broadband photocurrent enhancements in GaAs photodiodes. Sci Rep 2013; 3:2874. [PMID: 24096686 PMCID: PMC3791440 DOI: 10.1038/srep02874] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 09/18/2013] [Indexed: 12/21/2022] Open
Abstract
We illustrate the important trade-off between far-field scattering effects, which have the potential to provide increased optical path length over broad bands, and parasitic absorption due to the excitation of localized surface plasmon resonances in metal nanoparticle arrays. Via detailed comparison of photocurrent enhancements given by Au, Ag and Al nanostructures on thin-film GaAs devices we reveal that parasitic losses can be mitigated through a careful choice of scattering medium. Absorption at the plasmon resonance in Au and Ag structures occurs in the visible spectrum, impairing device performance. In contrast, exploiting Al nanoparticle arrays results in a blue shift of the resonance, enabling the first demonstration of truly broadband plasmon enhanced photocurrent and a 22% integrated efficiency enhancement.
Collapse
|
92
|
Akieda-Asai S, Koda S, Sugiyama M, Hasegawa K, Furuya M, Miyazato M, Date Y. Metabolic features of rats resistant to a high-fat diet. Obes Res Clin Pract 2013; 7:e243-50. [DOI: 10.1016/j.orcp.2013.01.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 01/10/2013] [Accepted: 01/21/2013] [Indexed: 11/25/2022]
|
93
|
Fukuda T, Matsuda H, Doi S, Sugiyama M, Morita Y, Yamada M, Yokoyama H, Minatoya K, Kobayashi J, Naito H. Evaluation of Automated 2D-3D Image Overlay System Utilizing Subtraction of Bone Marrow Image for EVAR: Feasibility Study. Eur J Vasc Endovasc Surg 2013; 46:75-81. [DOI: 10.1016/j.ejvs.2013.04.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 04/04/2013] [Indexed: 11/25/2022]
|
94
|
Hirai M, Kimura R, Takeuchi K, Sugiyama M, Kasahara K, Ohta N, Farago B, Stadler A, Zaccai G. Change of dynamics of raft-model membrane induced by amyloid-β protein binding. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:74. [PMID: 23852578 DOI: 10.1140/epje/i2013-13074-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 02/25/2013] [Accepted: 04/22/2013] [Indexed: 06/02/2023]
Abstract
While the steady-state existence in the size and shape of liquid-ordered microdomains in cell membranes, the so-called "lipid rafts", still remain the subject of debate, glycosphingolipid-cholesterol rich regions in plasma membranes have been considered to have a function as platforms for signaling and sorting. In addition, recent spectroscopic studies show that the interaction between monosialoganglioside and amyloid beta (Aβ protein promotes the transition of Aβ from the native structure to the cross-beta fold in amyloid aggregates. However, there is few evidence on the dynamics of "lipid rafts" membranes. As the neutron spin-echo (NSE) technique is well known to detect directly slow dynamics of membrane systems in situ, by the combination of NSE and small-angle X-ray scattering we have studied the effect of the interaction between raft-model membrane and amyloid Aβ proteins on the structure and dynamics of a large uni-lamellar vesicle (LUV) consisting of monosialoganglioside-cholesterol-phospholipid ternary mixtures as a model of lipid-raft membrane. We have found that the interaction between the Aβ proteins and the model membrane at the liquid crystal phase significantly suppresses a bending-diffusion motion with a minor effect on the LUV structure. The present results would suggest a possibility of non-receptor-mediated disorder in signaling through a modulation of a membrane dynamics induced by the association of amyloidogenic peptides on a plasma membrane.
Collapse
|
95
|
Sakamoto T, Tanaka Y, Watanabe T, Iijima S, Kani S, Sugiyama M, Murakami S, Matsuura K, Kusakabe A, Shinkai N, Sugauchi F, Mizokami M. Mechanism of the dependence of hepatitis B virus genotype G on co-infection with other genotypes for viral replication. J Viral Hepat 2013; 20:e27-36. [PMID: 23490386 DOI: 10.1111/jvh.12022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Accepted: 09/01/2012] [Indexed: 12/12/2022]
Abstract
Hepatitis B virus (HBV) is classified into several genotypes. Genotype G (HBV/G) is characterised by worldwide dispersion, low intragenotypic diversity and a peculiar sequence of the precore and core region (stop codon and 36-nucleotide insertion). As a rule, HBV/G is detected in co-infection with another genotype, most frequently HBV/A2. In a previous in vivo study, viral replication of HBV/G was significantly enhanced by co-infection with HBV/A2. However, the mechanism by which co-infection with HBV/A2 enhances HBV/G replication is not fully understood. In this study, we employed 1.24-fold HBV/A2 clones that selectively expressed each viral protein and revealed that the core protein expressing construct significantly enhanced the replication of HBV/G in Huh7 cells. The introduction of the HBV/A2 core promoter or core protein or both genomic regions into the HBV/G genome showed that both the core promoter and core protein are required for efficient HBV/G replication. The effect of genotype on the interaction between foreign core protein and HBV/G showed that HBV/A2 was the strongest enhancer of HBV/G replication. Furthermore, Western blot analysis of Dane particles isolated from cultures of Huh7 cells co-transfected by HBV/G and a cytomegalovirus (CMV) promoter-driven HBV/A2 core protein expression construct indicated that HBV/G employed HBV/A2 core protein during particle assembly. In conclusion, HBV/G could take advantage of core proteins from other genotypes during co-infection to replicate efficiently and to effectively package HBV DNA into virions.
Collapse
|
96
|
Saeki A, Segawa T, Abe T, Sugiyama M, Arimoto T, Hara H, Hasebe A, Ohtani M, Tanizume N, Ohuchi M, Kataoka H, Kawanami M, Yokoyama A, Shibata K. Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci. Mol Oral Microbiol 2013; 28:267-80. [PMID: 23413817 DOI: 10.1111/omi.12023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/01/2013] [Indexed: 11/30/2022]
Abstract
This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.
Collapse
|
97
|
Kikuchi T, Masuda Y, Sugiyama M, Mitsumata T, Ohori S. Prototype of haptic device for sole of foot using magnetic field sensitive elastomer. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/412/1/012036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
98
|
Sugiyama M, Sahashi H, Kurimoto E, Takata SI, Yagi H, Kanai K, Sakata E, Minami Y, Tanaka K, Kato K. Spatial arrangement and functional role of α subunits of proteasome activator PA28 in hetero-oligomeric form. Biochem Biophys Res Commun 2013; 432:141-5. [PMID: 23376067 DOI: 10.1016/j.bbrc.2013.01.071] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 01/20/2013] [Indexed: 11/30/2022]
Abstract
A major form of proteasome activator PA28 is a heteroheptamer composed of interferon-γ-inducible α and β subunits, which share approximately 50% amino acid identity and possess distinct insert loops. This activator forms a complex with the 20S proteasome and thereby stimulates proteasomal degradation of peptides in an ATP-independent manner, giving rise to smaller antigenic peptides presented by major histocompatibility complex class I molecules. In this study, we performed biophysical and biochemical characterization of the structure and function of the PA28 hetero-oligomer. Deuteration-assisted small-angle neutron scattering demonstrated three α and four β subunits are alternately arranged in the heptameric ring. In this arrangement, PA28 loops surround the central pore of the heptameric ring (site for peptide entry). Activating the 20S proteasome with a PA28 mutant that lacked the α subunit loops cleaved model substrates longer than a nonapeptide with better efficiency when compared to wild-type PA28. Based on these data, we hypothesize that the flexible PA28 loops act as gatekeepers, which function to select the length of peptide substrates to be transported between the proteolytic chamber and the extra-proteasomal medium.
Collapse
|
99
|
Ichigo S, Sugiyama M, Murase T, Ikeda T, Imai A. An autopsy case of acute aortic dissection during postpartum period. CLIN EXP OBSTET GYN 2013; 40:435-436. [PMID: 24283183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Aortic dissection in young women without Marfan disease is related in most instances to pregnancy. This is a potentially catastrophic occurrence. CASE An autopsy case of acute aortic dissection type B (Stanford classification), clinically undiagnosed during late puerperium period in a young woman with no discernible risk factors (e.g. family history and signs of connective tissue diseases) is presented. Autopsy with ancillary investigations revealed that knowledge of this albeit relatively rare complication of postpartum may assist the clinician in earlier diagnosis and referral of patients for surgical treatment. CONCLUSION This case is presented to raise awareness and review the literature for the critical care of postpartum patients.
Collapse
|
100
|
Kawamura J, Kotoura S, Okuyama T, Furumoto M, Fuchuu H, Miake K, Sugiyama M, Ohnishi M. Effect of Oral Administration of Defatted Chicken Skin Powder on Dry Skin in Humans. J JPN SOC FOOD SCI 2013. [DOI: 10.3136/nskkk.60.218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|