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Accelerated biodegradation of nitrophenols in the rhizosphere of Spirodela polyrrhiza

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Journal of Environmental Sciences 2012年第5期24卷 800-807页

作者： Risky Ayu Kristanti Masahiro Kanbe tadashi toyama Yasuhiro tanaka kazuhiro Mori Interdisciplinary Graduate School of Medicine and Engineering University of Yamanashi 4-3-11 Takeda Kofu Yamanashi 400-8511 Japan

We investigated the biodegradation of 2-nitrophenol （2-NP）, 4-nitrophenol （4-NP）, and 2,4-dinitrophenol （2,4-DNP） in the rhizosphere of Spirodela polyrrhiza plants by conducting degradation experiments with three river water samples supplemented with each nitrophenol （NP）. We then isolated NP-degrading bacteria both from the S. polyrrhiza roots and from the river water. In the river water samples, removal of the three NP was accelerated in the presence of S. polyrrhiza plants. the three NPs persisted in an autoclaved solution with sterile plants suggests that NP removal was accelerated largely by bacterial NP biodegradation rather than by adsorption and uptake by the plants. We isolated 8 strains of NP-degrading bacteria： 6 strains from the S. polyrrhiza roots and 2 strains from river water without the plants. the 2-NP- and 2,4-DNP-degrading bacteria were isolated only from the S. polyrrhiza roots. the 4-NP- degrading bacteria different from those isolated from the river water samples were also found on S. polyrrhiza roots. the 2-NP- and 4-NP-degrading strains isolated from the roots utilized the corresponding NP （0.5 mmol/L） as the sole carbon and energy source. the 2,4-DNP-degrading strains isolated from the roots showed substantial 2,4-DNP-degrading activity, but the presence of other carbon and energy sources was required for their growth. the isolated NP-degrading bacteria from the roots must have contributed to the accelerated degradation of the three NPs in the rhizosphere of S. polyrrhiza. Our results suggested that rhizoremediation with S. polyrrhiza may be effective for NP-contaminated surface water.

关键词： Spirodela polyrrhiza rhizosphere nitrophenol biodegradation

Diversity of culturable heterotrophic bacteria from the Mariana trench and their ability to degrade macromolecules

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Marine Life Science & technology 2020年第2期2卷 181-193页

作者： Xiuxiu Zhao Jiwen Liu Shun Zhou Yanfen Zheng Yanhong Wu kazuhiro Kogure Xiao-Hua Zhang MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life SciencesOcean University of China.Qingdao 266003China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Institute of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China Atmosphere and Ocean Research Institute The University of Tokyo5-1-5.Kashiwanoha.KashiwaChiba 277-8564Japan

the Mariana trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic *** culturable microorganisms from the Mariana trench will contribute to a further understanding of hadal biogeochemical processes and act as a unique microbial reservoir with potential ***,825 bacterial strains,identified by 16S rRNA gene sequencing,were isolated from 12 water depths(0-10,400 m)of the Mariana trench with 2216E and R2A media at 4℃ or 28℃ on four cruises during *** bacteria belong to four phyla,nine classes,27 orders,45 families and 108 ***,Gammaproteobacteria,Actinobacteria_c,Bacilli and Flavobacteriia were the most abundant classes,accounting for 37.9%,33.0%,11.8%,8.6%and 8.0%of the total bacterial isolates,respectively.2216E and R2A media were found to have a better selectivity to Bacilli and Flavobacteriia,*** strains were potential novel bacterial species with a 16S rRNA gene similaritytage of novel strains were obtained from R2A than 2216E ***,301(150 species)out of 354 strains(178 species)selected from each depth could degrade at least one of the ten kinds of macromolecules *** results indicate that there is a high diversity of culturable bacteria in the Mariana trench and they can produce a variety of extracellular *** study provides a valuable resource of microorganisms for investigating their biogeochemical roles in the Mariana trench and for industrial applications.

关键词： Diversity Heterotrophic bacteria the Mariana trench Macromolecule Water column

Re-evaluation of the mechanical properties and creep resistance of commercial magnesium die-casting alloy AE44

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Journal of Magnesium and Alloys 2021年第5期9卷 1552-1560页

作者： Suming Zhu trevor B.Abbott Jian-Feng Nie Hua Qian Ang Dong Qiu kazuhiro Nogita Mark A.Easton School of Engineering RMIT UniversityCarltonVictoria 3053Australia Department of Materials Science and Engineering Monash UniversityVictoria 3800Australia Magontec Limited SydneyNew South Wales 2000Australia School of Mechanical and Mining Engineering The University of QueenslandSt LuciaQueensland 4072Australia

this paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44(Mg-4Al-4RE)in light of the influence of minor Mn *** is shown that the Mn-containing AE44 exhibits distinct age hardening response upon direct ageing(t5)due to the precipitation of nanoscale Al-Mn particles,as reported previously in a similar *** t5 ageing leads to a significant improvement in strength with similar ***,the t5-aged AE44 has a remarkably better strength-ductility combination than most Mg die-casting alloys and even the Al die-casting alloy *** Mn addition is also shown to be critical for the creep resistance of AE44 whereas the influence of the RE constituent is not as significant as previously thought,which reaffirms that precipitation hardening of theα-Mg matrix is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of die-cast Mg *** findings in this work could provide new application perspectives for AE44,particularly in the automotive industry.

关键词： Magnesium alloys Manganese Precipitation hardening Mechanical properties Creep Die casting

Impaired glucose tolerance in acute pancreatitis

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World Journal of Gastroenterology 2015年第24期21卷 7367-7374页

作者： kazuhiro Kikuta Atsushi Masamune tooru Shimosegawa Division of Gastroenterology Tohoku University Graduate School of Medicine

Acute pancreatitis(AP) is an acute inflammatory disease of the exocrine pancreas. In spite of the pivotal role of the endocrine pancreas in glucose metabolism, the impact of impaired glucose tolerance on AP has not been fully elucidated. A meta-analysis of seven observational studies showed that type 2 diabetes mellitus(DM) was associated with an increased risk of AP. the increased risk of AP shown in the meta-analysis was independent of hyperlipidemia, alcohol use and gallstones. Antidiabetic drugs including incretins might increase the risk of AP, but no intervention trials have confirmed this. Although a controversial finding, DM seems to be associated with severe attacks and organ failure in AP. We analyzed the results of a nationwide epidemiological survey of AP in Japan. We studied the impact of pre-existing DM on the clinical course of AP in 1954 cases for which information on DM status was available at the onset of AP. the prevalence of DM in AP patients(12.8%) was higher than that in the general population in Japan(10.5%). AP patients with DM had higher morbidity of cardiovascular and renal failure than those without DM. About 35% of the idiopathic AP patients with DM had renal failure. the mortality of AP patients with DM(4.0%) was higher than that of AP patients without DM(1.7%). If stratified by etiology, idiopathic, but not alcoholic or biliary, AP patients with DM were predisposed to increased mortality(9.7%). In conclusion, impaired glucose tolerance might have an impact on the development and clinical outcome of AP. However, the impact might depend on the cause of hyperglycemia, the condition of DM including severity, duration and treatment, and the characteristics of the AP patients including age, etiology and comorbidity.

关键词： Alcohol Diabetes mellitus Epidemiology Gallstone Mortality Organ failure

Effects of fibril- or fixed-collagen on matrix metalloproteinase-1 and tissue inhibitor of matrix metalloproteinase-1 production in the human hepatocyte cell line HLE

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World Journal of Gastroenterology 2005年第15期11卷 2264-2268页

作者： Makoto Nakamuta kazuhiro Kotoh Munechika Enjoji Hajime Nawata Department of Medicine and Bioregulatory Science

AIM:Matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of matrix metalloproteinase-1 (tIMP-1) are central to the spontaneous resolution of liver fibrosis. the mechanisms involved have been investigated in hepatic stellate cells (HSC), but not in hepatocytes. We investigated the effects of fibril- and fixed-collagen on MMP-1 and tIMP-1 production in hepatocytes, using the HLE cell line. MEtHODS: Fibril type I and IV collagen were prepared by HCI digestion of type I and IV collagen, respectively. For fixed-collagen, culture dishes were coated with fibril type I or IV collagen and fixed by ultraviolet. type I collagenase activity was measured using fluorescein isothiocyanate-labeled type I collagen. MMP-1 and tIMP-1 in HLE cells were measured by a one-step sandwich enzyme immunoassay. RESULtS: Both fibril type I and IV collagen significantly increased type I collagenase activity about two-fold compared with no fibril collagen. the effects of the fibril collagen were not affected by the coating condition. there was no significant difference in the effects on collagenase activity between cells cultured in medium containing fibril type I collagen and those cultured in the presence of type IV collagen. Both types of fibril collagen significantly increased MMP-1 production, and showed more than 10-fold higher levels of MMP-1 than the control. the enhanced MMP-1 production by fibril collagens was unaffected by the coating condition. By contrast, tIMP-1 production was not changed by the addition of fibril type I or IV collagen, and neither was it affected by the coating conditions. Coating with type I collagen significantly suppressed MMP-1 production by almost one-tenth compared with no coating. By contrast, tIMP-1 production was not affected by either the absence of a collagen coat or by increasing the concentration of the coating collagen. CONCLUSION: these results indicated that, in HLE cells, fibril- and fixed-collagen have opposite effects on MMP-1 production witho

关键词： Hepatocyte Fibril-collagen Fixed collagen

Predictors of kidney tubular dysfunction induced by adefovir treatment for chronic hepatitis B

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World Journal of Gastroenterology 2015年第7期21卷 2116-2123页

作者： Motohiro Shimizu Norihiro Furusyo Hiroaki Ikezaki Eiichi Ogawa takeo Hayashi takeshi Ihara Yuji Harada kazuhiro t.yoda Masayuki Murata Jun Hayashi Department of General Internal Medicine Kyushu University Hospital Kyushu General Internal Medicine Center Haradoi Hospital

AIM:to investigate the predictors of proximal kidney tubular dysfunction(PKtD)induced by adefovir dipivoxil(ADV)treatment for chronic hepatitis ***:Seventy-nine patients(age at the evaluation of PKtD:56.9±10.7 years)with chronic hepatitis B undergoing long-term oral antiviral nucleos(t)ide analogue treatment were consecutively *** was defined by the presence of at least two of the following five abnormalities:phosphate diabetes,nondiabetic glucosuria,metabolic acidosis,β2-microglobulinuria,or renal *** single-nucleotide polymorphisms(SNPs)in the SLC22A6 gene encoding human organic anion transporter 1(h OAt1)and ABCC2 encoding multidrug resistance protein 2(MRP2)were analyzed using the taq Man Allelic Discrimination Demonstration ***:Nine(30.0%)of the 30 ADV-treated patients were diagnosed with PKtD,while no patients without ADV developed PKtD(Pthree patients with ADV were diagnosed with symptomatic *** the patients who took ADV,those with PKtD were of higher age at initiation,had significantly longer treatment duration,and had a significantly lower body mass index than those without *** incidence of PKtD dramatically increased after 96 mo from the start of ADV *** contrast,the SNPs were not correlated with *** regression analysis extracted older age at initiation(OR=5.0,95%CI:1.1-23.4;P=0.040)and longer treatment duration(OR=3.2,95%CI:1.2-8.6;P=0.020)as significant factors associated with ***:Our results suggest that the tubular function of the kidney of older patients undergoing longterm ADV treatment should be carefully evaluated.

关键词： Adefovir dipivoxil Proximal kidney tubular dysfunc

Establishment and characterization of a rat pancreatic stellate cell line by spontaneous immortalization

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World Journal of Gastroenterology 2003年第12期9卷 2751-2758页

作者： Atsushi Masamune Masahiro Satoh kazuhiro Kikuta Noriaki Suzuki tooru Shimosegawa Division of Gastroenterology Tohoku University Graduate School of MedicineSendaiJapan A.M.and M.S.equally contributed to this work

AIM: Activated pancreatic stellate cells (PSCs) have been implicated in the pathogenesis of pancreatic fibrosis and inflammation. Primary PSCs can be subcultured only several times because of their limited growth potential. A continuous cell line may therefore be valuable in studying molecular mechanisms of these pancreatic disorders. the aim of this study was to establish a cell line of rat PSCs by spontaneous ***: PSCs were isolated from the pancreas of male Wistar rats, and conventional subcultivation was performed repeatedly. telomerase activity was measured using the telomere repeat amplification protocol. Activation of transcription factors was assessed by electrophoretic mobility shift *** of mitogen-activated protein (MAP) kinases was examined by Western blotting using anti-phosphospecific antibodies. Expression of cytokine-induced neutrophil chemoattractant-1 was determined by enzyme ***: Conventional subcultivation yielded actively growing cells. One clone was obtained after limiting dilution,and designated as SIPS. this cell line has been passaged repeatedly more than 2 years, and is thus likely *** cells retained morphological characteristics of primary,culture-activated PSCs. SIPS expressed α-smooth muscle actin, glial acidic fibrillary protein, vimentin, desmin, type Ⅰ collagen, fibronectin, and prolyl hydroxylases. telomerase activity and p53 expression were negative. Proliferation of SIPS cells was serum-dependent, and stimulated with platelet-derived growth factor-BB through the activation of extracellular signal-regulated kinase. Interleukin-1β activated nuclear factor-κB, activator protein-1, and MAP ***-1β induced cytokine-induced neutrophil chemoattractant-1 expression through the activation of nuclear factor-κB and MAP ***: SIPS cells can be useful for in vitro studies of cell biology and signal transduction of PSCs.

关键词： Animals Base Sequence Cell Culture techniques Cell Line, transformed Cells, Cultured Cystic Fibrosis Cytoskeletal Proteins Extracellular Matrix Proteins Immunohistochemistry NF-kappa B Oligonucleotide Probes Pancreas Rats Research Support, Non-U.S. Gov't transcription Factor AP-1

Depletion of CD25^+CD4^+t cells (tregs) enhances the HBV-specific CD8^+ t cell response primed by DNA immunization

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World Journal of Gastroenterology 2005年第24期11卷 3772-3777页

作者： Yoshihiro Furuichi Hirotake tokuyama Satoshi Ueha Makoto Kurachi Fuminori Moriyasu kazuhiro Kakimi Fourth Department of Internal Medicine (Gastroenterology and Hepatology) Department of Molecular and Preventive Medicine Department of Immunotherapeutics (Medinet)

AIM: Persistent hepatitis B virus (HBV) infection is characterized by a weak CD8+ t cell response to HBV. Immunotherapeutic strategies that overcome tolerance and boost these suboptimal responses may facilitate viral clearance in chronically infected individuals. therefore, we examined whether CD25+CD4+ regulatory t (treg) cells might be involved in a inhibition of CD8+t cell priming or in the modulation of the magnitude of the 'peak' antiviral CD8+ t cell response primed by DNA immunization. MEtHODS: B10.D2 mice were immunized once with plasmid pCMV-S. Mice received 500 μg of anti-CD25 mAb injected intraperitoneally 3 d before DNA immunization to deplete CD25+ cells. Induction of HBV-specific CD8+ t cells in peripheral blood mononuclear cells (PBMCs) was measured by S28-39 peptide loaded DimerX staining and their function was analyzed by intracellular IFN-γ staining. RESULtS: DNA immunization induced HBV-specific CD8+ t cells. At the peak t cell response (d 10), 7.1±2.0% of CD8+ t cells were HBV-specific after DNA immunization, whereas 12.7±3.2% of CD8+ t cells were HBV-specific in treg-depleted mice, suggesting that DNA immunization induced more antigen-specific CD8+ t cells in the absence of CD25+ treg cells (n = 6, Pt cells were detected in the presence of these cells (1.3±0.4%) in comparison to treg-depleted mice (2.6±0.9%) on d 30 after DNA immunization (n - 6, Pth IFN-γ production and the avidity of the HBV-specific CD8+ t cell response to antigen were higher in HBV-specific CD8+ t cells induced in the absence of treg cells. CONCLUSION: CD25+ treg cells suppress priming and/or expansion of antigen-specific CD8+ t cells during DNA immunization and the peak CD8+ t cell response is enhanced by depleting this cell population. Furthermore, treg cells appear to be involved in the contraction phase of the CD8+ t cell response and may affect the quality of memory t cell pools. the elimination of treg cells or the

关键词： Hepatitis B virus Regulatory t cell (treg) Cytotoxic t lymphocyte DNA immunization Vaccine

Involvement of Sphingosine 1-Phosphate (S1P) Receptor type 1 and type 4 in Migratory Response of Mouse t Cells toward S1P

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Cellular & Molecular Immunology 2006年第6期3卷 429-437页

作者： Hirofumi Matsuyuki Yasuhiro Maeda kazuhiro Yano Kunio Sugahara Kenji Chiba takayuki Kohno Yasuyuki Igarashi Research Laboratory III (Immunology) Pharmaceuticals Research Division Mitsubishi Pharma Corporation Yokohama Japan Discovery technology Laboratory Pharmaceuticals Research Division Mitsubishi Pharma Corporation Yokohama Japan Department of Biomembrane and Biofunctional Chemistry Graduate School of Pharmaceutical Sciences Hokkaido University Sapporo Japan

Sphingosine 1-phosphate （S1P）, a pleiotropic lysophospholipid, regulates signal transduction pathway via Gprotein-coupled receptors termed S1P1-5 in several types of the cells including lymphocytes. Higher levels of S1P4 mRNA as well as S1P1 mRNA are expressed in lymphoid tissues such as the spleen, thymus, lymph nodes, and Payer＇s patches. In contrast to S1P1 that plays an essential role in lymphocyte egress, little is known about the role of S1P4 in immune system. In this study, we found that S1P at 10 to 100 nM significantly induced the cell migration and the significant levels of S1P1 and S1P4 mRNA were expressed in mouse CD4 t cells, D10.G4.1 mouse th2 cells, and ***-2 mouse thymoma cells. In D10.G4.1 and ***-2 cells, S1P-induced migration was almost completely inhibited by pretreatment with pertussis toxin, Clostoridium difficile toxin B, and （S）-enantiomer of FtY720-phosphate, a potent agonist at S1P1 and S1P4. the members of the Rho family small GtPase, Cdc42 and Rac were activated by S1P stimulation in these cells. the transfection with dominant negative or constitutively active forms of Cdc42 and Rac revealed that the activation of both Cdc42 and Rac is essential for S1P-induced migration of these cells. the immunoprecipitation assays using CHO cells co-expressing both S1P4 and S1P1 receptors indicated that S1P4 and S1P1 are associated on the cell surface. these results suggest that the association of S1P4 and S1PI plays an important role in migratory response of mouse t cells toward S1P.

关键词： S1Pi S1P4 S1P FtY720 t cell migration