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2.
Phys Rev Lett ; 117(8): 082503, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27588852

RESUMO

We present an improved search for neutrinoless double-beta (0νßß) decay of ^{136}Xe in the KamLAND-Zen experiment. Owing to purification of the xenon-loaded liquid scintillator, we achieved a significant reduction of the ^{110m}Ag contaminant identified in previous searches. Combining the results from the first and second phase, we obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>1.07×10^{26} yr at 90% C.L., an almost sixfold improvement over previous limits. Using commonly adopted nuclear matrix element calculations, the corresponding upper limits on the effective Majorana neutrino mass are in the range 61-165 meV. For the most optimistic nuclear matrix elements, this limit reaches the bottom of the quasidegenerate neutrino mass region.

3.
Transplant Proc ; 46(3): 770-3, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767345

RESUMO

BACKGROUND: Interferon (IFN) therapy is a well-established antiviral treatment for hepatitis C virus (HCV) - infected patients. However, susceptibility to thrombocytopenia is a major obstacle in its initiation or continuation, particularly in patients with HCV who underwent liver transplantation (LT). We previously showed that the coexistence of splenomegaly and thrombocytopenia could result in persistent thrombocytopenia after LT. Here we retrospectively evaluated the validity of this criterion for simultaneous splenectomy in recipients with HCV. PATIENTS AND METHODS: Subjects included 36 recipients with HCV who received LT between January 2006 and February 2012 at Hiroshima University. We analyzed the spleen volume, body surface area, platelet (PLT) count, and rate of completion or continuation with IFN therapy in these recipients. RESULT: Of these recipients, 30 did not require simultaneous splenectomy according to the criterion, and 24 actually did not receive simultaneous splenectomy. In this group, 21 (87.5%) started IFN therapy. Fifteen (71.4%) of these recipients completed or continued IFN therapy, whereas 13 (61.9%) achieved either a sustained virological response (SVR) or an end-of-treatment response. The PLT count increased to >100,000/mm(3) 1 month after LT in 16 (66.7%) recipients from this group. CONCLUSION: Our criterion detected the PLT count outcome after LT in recipients with HCV and achieved a better SVR result after IFN therapy.


Assuntos
Hepatite C/cirurgia , Transplante de Fígado , Esplenectomia , Hepatite C/tratamento farmacológico , Humanos , Interferons/uso terapêutico , Estudos Retrospectivos , Trombocitopenia/cirurgia
4.
Transplant Proc ; 46(3): 790-3, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767350

RESUMO

BACKGROUND: CXC motif chemokine 10 (CXCL10), known as interferon-γ-induced protein 10, is an inflammatory cytokine secreted by various cells in response to interferon-γ. CXCR3, the receptor of CXCL10, is predominantly expressed on activated T, B, natural killer, and dendritic cells, as well as macrophages. CXCR3 promotes chemotaxis upon binding CXCL10. Serum CXCL10 levels have recently attracted attention as a post-transplantation biomarker for graft rejection. However, the correlation between the degree of T cell response to allostimulation and CXCL10 levels remains unclear. In this study, we investigated the serum and bile CXCL10 levels of patients who underwent living donor liver transplantation (LDLT) and compared them with the T cell responses to allostimulation. PATIENTS AND METHODS: Between February 2009 and August 2012, 41 patients underwent LDLT at Hiroshima University Hospital. Serum and bile CXCL10 levels were measured weekly for 4 weeks after surgery, while the T cell responses to allostimulation were evaluated using a mixed lymphocyte reaction with an intracellular carboxyfluorescein diacetate succinimidyl ester-labeling technique that we regularly use to monitor the immune response to anti-donor and anti-third-party stimulation after liver transplantation. The stimulation index (SI) and CD25 expression of the CD4+ and CD8+ T cell subsets in response to allostimulation were then analyzed using flow cytometry. RESULTS: Serum CXCL10 levels were significantly correlated with the SI values for CD8+ T cells in response to both types of allostimulation. Bile CXCL10 levels were significantly correlated with CD25 expression of CD8+ T cell subsets, especially in response to anti-donor stimulation. Patients with higher bile CXCL10 levels suffered from severe acute cellular rejection that was refractory to steroid pulse. CONCLUSION: Measurements of bile CXCL10 levels could predict anti-donor cytotoxic T cell responses in liver transplant recipients.


Assuntos
Bile/metabolismo , Quimiocina CXCL10/metabolismo , Transplante de Fígado , Linfócitos T Citotóxicos/imunologia , Doadores de Tecidos , Humanos
5.
J Phys Condens Matter ; 24(39): 395007, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-22941928

RESUMO

We report a study of the surface temperature (T(s)) dependence of Cu(2)O formation on a Cu(110) surface induced by a hyperthermal O(2) molecular beam (HOMB), using x-ray photoemission spectroscopy in conjunction with synchrotron radiation. From the T(s) dependence of the O uptake curves, the direct dissociative adsorption process mainly contributes to the formation of the p(2 × 1)-O structure with an O coverage (Θ) of 0.5 ML for 2.2 eV HOMB incidence. On the other hand, the rate of oxidation at Θ > 0.5 ML, particularly in Cu(2)O formation, strongly depends on the T(s). Thicker Cu(2)O islands were found inhomogeneously at 400 and 500 K, suggesting the dominant role of the migration of Cu atoms in the Cu(2)O formations on the Cu(110) surface.

6.
Transplant Proc ; 44(5): 1446-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22664033

RESUMO

BACKGROUND: When the kidney from a living donor with a double inferior vena cava (IVC) is harvested for renal transplantation, the short length of the renal vein may eventually create a technical problem for graft implantation. Herein, we have reported a rare case of renal vein extension using an autologous renal vein in a living donor with a double IVC. CASE REPORT: A 70-year-old man with end-stage renal disease owing to autosomal-dominant polycystic kidney disease underwent a living donor kidney graft from his wife who had a double IVC. Because of the enlarged kidneys, the patient underwent a bilateral native nephrectomy with concomitant renal transplantation to create space in the pelvis. At nephrectomy, the recipient's renal vein was used to extend the donor renal vein. On the back table, the vein graft was sutured to the donor renal vein, permitting a 3.0-cm extension. RESULTS: The transplantation was performed safely without any complications; the recipient's renal function and blood flow were excellent after the operation. CONCLUSION: This case illustrated that an autologous renal vein graft is a preferable option to extend of short donor renal vein for recipients who require a simultaneous native nephrectomy.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Doadores Vivos , Veias Renais/transplante , Veia Cava Inferior/anormalidades , Idoso , Feminino , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Nefrectomia , Flebografia/métodos , Rim Policístico Autossômico Dominante/complicações , Veias Renais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Transplante Autólogo , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem
7.
J Hazard Mater ; 186(1): 796-804, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21163572

RESUMO

Cu-Mn based mixed oxide type low-cost catalysts have been prepared in supported form using mesoporous Al(2)O(3), TiO(2) and ZrO(2) supports. These supports have been prepared by templating method using a natural biopolymer, chitosan. The synthesized catalysts have been characterized by XRD, BET-SA, SEM, O(2)-TPD and TG investigations. The catalytic activity for CO as well as PM oxidation was studied, in a view of their possible applications in the control of emissions from solid fuel combustion of rural cook-stoves. The trend observed for the catalytic activity of the synthesized catalysts for CO oxidation was ZrO(2)>TiO(2)>Al(2)O(3) while for PM oxidation it was observed to be TiO(2)>ZrO(2)>Al(2)O(3). The effect of CO(2), SO(2) and H(2)O on CO oxidation activity was also investigated, and despite partial deactivation, the catalysts show good CO oxidation activity. An effective regeneration treatment was attempted by heating the partially deactivated catalysts in presence of oxygen. Redox properties of TiO(2) and ZrO(2) and their structure appeared to be responsible for their promotional activity for CO and PM oxidation reactions. These unordered mesoporous materials could be useful for such reactions where mass transfer is more important than shape and size selectivity.


Assuntos
Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Custos e Análise de Custo , Catálise , Microscopia Eletrônica de Varredura , Oxirredução , Tamanho da Partícula , Temperatura , Difração de Raios X
8.
Phys Rev Lett ; 100(25): 256104, 2008 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-18643679

RESUMO

We report results of our study on the surface-temperature dependence of the steric effect in the dissociative adsorption of NO on Si(111)-(7x7). Data presented here show that, at an incident energy of 58 meV, the reactive sticking probability for the N-end collision is larger than that for the O-end collision. Furthermore, this steric preference is quite sensitive to the surface temperature and the surface coverage. This study shows that the transient surface trapping into a shallow precursor well plays a key role in the stereodynamics of the dissociative adsorption at the low energy region.

9.
J Biol Chem ; 276(50): 47702-8, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11595738

RESUMO

Transfer-messenger RNA (tmRNA) is a stable RNA in bacteria of 360 +/- 40 nucleotides that can be charged with alanine and can function as both tRNA and mRNA. Ribosomes that are stalled either in a coding region of mRNA or at the 3' end of an mRNA fragment lacking a stop codon are rescued by replacing their mRNA for tmRNA. Here we demonstrate that the interaction of tmRNA with the elongation factor Tu shows unexpected features. Deacylated tmRNA can form a complex with either EF-Tu.GDP or EF-Tu.GTP, the association constants are about one order of magnitude smaller than that of an Ala-tRNA.EF-Tu.GTP complex. tmRNA as well as Ala-tmRNA can be efficiently cross-linked with EF-Tu.GDP using a zero-length cross-link. The efficiency of cross-linking in the case of deacylated tmRNA does not depend on an intact CCA-3' end and is about the same, regardless whether protein mixtures such as the post-ribosomal supernatant (S100 enzymes) or purified EF-Tu are present. Two cross-linking sites with EF-Tu.GDP have been identified that are located outside the tRNA part of tmRNA, indicating an unusual interaction of tmRNA with EF-Tu.GDP.


Assuntos
Fator Tu de Elongação de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Sistema Livre de Células , Códon de Terminação , Reagentes de Ligações Cruzadas/farmacologia , Escherichia coli/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Cinética , Modelos Biológicos , Fator Tu de Elongação de Peptídeos/genética , Plasmídeos/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , RNA/metabolismo , RNA de Transferência/metabolismo , Aminoacil-RNA de Transferência/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tripsina/farmacologia
10.
Tissue Antigens ; 55(3): 206-11, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10777095

RESUMO

Psoriasis vulgaris is associated with the HLA-Cw6 and Cw7 antigens. We have previously narrowed down the critical region most likely to contain the psoriasis vulgaris gene to 111 kb spanning 89 kb to 200 kb telomeric of the HLA-C locus by microsatellite mapping. This segment includes three known genes (POU5F1, SC1 and S) and four new expressed genes. Among them, SC1 (TCF19) is the cell growth regulated gene possibly with trans-activator activity. Since psoriasis vulgaris is a common skin disorder characterized by hyperproliferation of epidermal cells, it is tempting to speculate that the SCI gene is one of the strong candidate genes responsible for the development of psoriasis vulgaris. Here, we investigated genetic polymorphisms in the SC1 gene by direct DNA sequencing and polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) techniques. Three single nucleotide polymorphisms in exon 2, two of which are accompanied by amino-acid substitutions, were identified. Further, one 4-bp deletion polymorphism was detected around the acceptor site of the lariat-shaped structure necessary for RNA splicing in intron 2. No significant difference in the dimorphic or haplotypic distribution at these four polymorphic sites was observed between the patients with psoriasis vulgaris and healthy controls. This suggests that the susceptible gene for psoriasis vulgaris is not the SC1 gene itself, although a unique homozygous haplotype was identified in the patients.


Assuntos
Antígenos HLA-C/genética , Polimorfismo Genético , Psoríase/genética , Telômero , Fatores de Transcrição/genética , Sequência de Bases , Divisão Celular , DNA Complementar , Humanos , Dados de Sequência Molecular , Psoríase/imunologia
11.
Immunogenetics ; 49(5): 384-94, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10199914

RESUMO

Class I genomic clones of the quail (Coturnix japonica) major histocompatibility complex (MhcCoja) were isolated and characterized. Two clusters spanning the 90.8 kilobase (kb) and 78.2 kb class I gene regions were defined by overlapping cosmid clones and found to contain at least twelve class I loci. However, unlike in the chicken Mhc, no evidence for the existence of any Coja class II gene was obtained in these two clusters. Based on comparative analysis of the genomic sequences with those of the cDNA clones, Coja-A, Coja-B, Coja-C, and Coja-D (Shiina et al. 1999), these twelve loci were assigned to represent one Coja-A gene, two Coja-B genes (Coja-B1 and -B2), four Coja-C genes (Coja-C1-C4), four Coja-D genes (Coja-D1-D4), and one new Coja-E gene. A class I gene-rich segment of 24.6 kb in which five of these genes (Coja-B1, -B2, -D1, -D2 and -E) are densely packed were sequenced by the shotgun strategy. All of these five class I genes are very compact in size [2089 base pairs (bp)-2732 bp] and contain no apparent genetic defect for functional expression. A transporter associated with the antigen processing (TAP) gene was identified in this class I gene-rich segment. These results suggest that the quail class I region is physically separated from the class II region and characterized by a large number of the expressible class I loci (at least seven) in contrast to the chicken Mhc, where the class I and class II regions are not clearly differentiated and only at most three expressed class I loci so far have been recognized.


Assuntos
Coturnix/genética , Genes MHC Classe I , Antígenos de Histocompatibilidade Classe I/genética , Transportadores de Cassetes de Ligação de ATP/genética , Sequência de Aminoácidos , Animais , Apresentação de Antígeno , Sequência de Bases , Galinhas/genética , Mapeamento de Sequências Contíguas , Cosmídeos , DNA Complementar/genética , Evolução Molecular , Biblioteca Genômica , Antígenos de Histocompatibilidade Classe I/classificação , Endogamia , Dados de Sequência Molecular , Família Multigênica , Filogenia , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
12.
J Synchrotron Radiat ; 5(Pt 3): 536-8, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15263570

RESUMO

An undulator beamline for spectroscopy studies focusing on the electronic structure of actinide materials is under construction. Linearly or circularly polarized soft X-rays are provided by employing a variably polarizing undulator. Varied-line-spacing plane gratings and a sagittal-focusing system are used to monochromatize the undulator beam, whose energy ranges from 0.3 to 1.5 keV. A resolving power of 10(4) is expected in the whole energy region. These components are methodically operated by the SPring-8 beamline control system. There are three experimental stations in the beamline. In one of the stations the photoemission spectroscopy experiments are carried out at a radioisotope-controlled area where actinide compounds as well as unsealed radioactive materials are usable. Other experimental stations are planned in the beamline for surface photochemical reactions and biological applications.

13.
J Synchrotron Radiat ; 5(Pt 1): 10-6, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16687795

RESUMO

This report presents the design of an undulator beamline at SPring-8 to be used for soft X-ray spectroscopy focused on radioactive materials. Photoemission spectroscopy experiments are carried out in a radioisotope (RI)-controlled area where actinide compounds as well as unsealed radioactive materials are usable. Intrusion of the radioactive materials into the electron storage ring or to the outside of the evacuated beamline components can be avoided by a specially devised RI protection/inspection mechanism. The combination of a variably polarizing undulator and a varied-line-spacing plane-grating monochromator provides linearly or circularly polarized soft X-rays with a high resolving power in the energy range 0.28-1.5 keV. The beamline will become operational in December 1997.

14.
Biochem Biophys Res Commun ; 228(3): 704-8, 1996 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-8941342

RESUMO

To investigate the role of four Cys residues of eukaryotic initiation factor (eIF)-4E in the recognition of the mRNA cap structure, single, double and quadruple mutant genes which encoded the Ala residues in the place of the respective Cys residues were prepared using a synthetic human eIF-4E gene by the site-directed mutagenesis, and were expressed in E. coli with the same way as the wild type. The cap binding abilities of respective mutated eIF-4Es were compared with that of the wild-type by m7GTP affinity chromatography. The results suggest that, although all four of Cys residues participate in the recognition of the mRNA cap structure, they contribute indirectly to the stabilization of overall tertiary structure, especially of the cap binding pocket, rather than by direct interaction. A comparison among the cap binding abilities of single, double and quadruple mutants indicated no existence of internal disulfide bonds in eIF-4E.


Assuntos
Fatores de Iniciação de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Escherichia coli/genética , Fator de Iniciação 4E em Eucariotos , Humanos , Mutagênese Sítio-Dirigida , Fatores de Iniciação de Peptídeos/genética , Ligação Proteica
15.
Eur J Biochem ; 239(3): 597-601, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8774702

RESUMO

In order to identify the amino acid residues necessary for the selective recognition of the mRNA cap structure by human eukaryotic initiation factor-4E (eIF-4E), which plays a central role in the first step of mRNA translation, we prepared recombinant wild-type and fourteen mutant forms and compared their cap-binding abilities by affinity chromatography. By the direct expression of a synthetic gene encoding human eIF-4E as the soluble form in Escherichia coli and the application on a 7-methylguanosine-5'-triphosphate-Sepharose 4B cap affinity column, pure recombinant eIF-4E was prepared; the optimum pH for the binding of the mRNA cap was 7.5. Among the amino acid residues conserved among various eIF-4E species, each of 14 functional residues was replaced with a nonpolar amino acid (alanine or leucine). All mutant eIF-4E genes, which were constructed by site-directed mutagenesis, were expressed in the same way as the wild type, and their cap-binding abilities were compared with that of the wild type. Consequently, all eight tryptophan residues. Glu103, and two histidine residues at positions 37 and 200 in human recombinant eIF-4E were suggested to be important for the recognition of the mRNA cap structure through direct interaction and/or indirect contributions. Indirect contributions included the construction of the overall protein structure, especially the cap-binding pocket.


Assuntos
Fatores de Iniciação de Peptídeos/metabolismo , Capuzes de RNA/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Escherichia coli/genética , Fator de Iniciação 4E em Eucariotos , Genes Sintéticos , Humanos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Fatores de Iniciação de Peptídeos/genética , Ligação Proteica , Análogos de Capuz de RNA/metabolismo , Proteínas Recombinantes/metabolismo , Solubilidade , Relação Estrutura-Atividade
16.
Biol Pharm Bull ; 18(5): 677-82, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7492981

RESUMO

The bioavailability of calcium from various calcium sources in humans and animals has been the subject of investigation for many years and there is considerable controversy as to the relative bioavailability of different calcium salts. Most of the studies have used a calcium balance technique which has numerous problems in terms of performance and interpretation. Using a method for evaluating the efficacy of calcium from calcium salts used for plasma calcium metabolism and bone mineralization, we examined the bioavailability of calcium from four commercially available calcium salts, namely calcium carbonate, DL-calcium lactate, L-calcium lactate and powdered oyster shell-calcium in vitamin D-deficient or -replete rats. Among the calcium salts, the differences in bioavailability were small and not statistically significant as tested by analysis of variance in both groups of rats. Thus, we conclude that calcium is utilized to the same extent from calcium carbonate, DL-calcium lactate, L-calcium lactate and powered oyster shell-calcium in both vitamin D-deficient and -replete rats.


Assuntos
Carbonato de Cálcio/farmacocinética , Lactatos/farmacocinética , Ostreidae/química , Deficiência de Vitamina D/metabolismo , Animais , Disponibilidade Biológica , Peso Corporal/fisiologia , Densidade Óssea , Osso e Ossos/fisiologia , Cálcio/sangue , Dieta , Ingestão de Alimentos/fisiologia , Ácido Láctico , Masculino , Pós , Ratos , Ratos Wistar , Vitamina D/sangue , Deficiência de Vitamina D/sangue
17.
Biol Pharm Bull ; 18(2): 372-6, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7742816

RESUMO

In order to obtain the active form of recombinant human initiation factor (eIF) 4E effectively, an artificial synthetic gene was cloned into an expression vector (pMAL-p2) and the soluble expression was attempted in Escherichia coli under the control of a tac promoter. Two expression systems were finally constructed as a fusion protein with maltose-binding protein, which contain a recognition sequence for the site specific protease alpha-thrombin and factor Xa, respectively. Most of the fusion protein was induced as a soluble form. The soluble human eIF-4E digested from the fusion protein showed binding specificity for the m7GTP affinity column.


Assuntos
Escherichia coli/genética , Genes Sintéticos , Fatores de Iniciação de Peptídeos/genética , Sequência de Aminoácidos , Sequência de Bases , Cromatografia de Afinidade , Clonagem Molecular , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Fator de Iniciação 4E em Eucariotos , Expressão Gênica , Humanos , Dados de Sequência Molecular , Fatores de Iniciação de Peptídeos/isolamento & purificação , Plasmídeos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
18.
Phys Rev A Gen Phys ; 32(6): 3742-3744, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9896547
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