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Differential effects on apoptosis induction in hepatocyte lines by stable expression of hepatitis B virus X protein

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World Journal of Gastroenterology 2006年第29期12卷 4673-4682页

作者： Nicola Fiedler Ellen Quant Ludger Fink Jianguang Sun Ralph Schuster Wolfram H Gerlich stephan schaefer Institut for Medizinische Virologie Justus-LiebigUniversitat Frankfurter Str. 107 D-35392 GieBen Germany Abteilung fǖr Innere Medizin Christian AlbrechtUniversitat Kiel Germany Zentrum fǖr Innere Medizin Justus-LiebigUniversitat GieBen Germany Abteilung Virologie Universitat Rostock Schillingallee 70 18055 Rostock Germany Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China

AIM： Hepatitis B virus protein X （HBx） has been shown to be weakly oncogenic in vitro. The transforming activities of HBx have been linked with the inhibition of several functions of the tumor suppressor p53. We have studied whether HBx may have different effects on p53 depending on the cell type. METHODS： We used the human hepatoma cell line HepG2 and the immortalized murine hepatocyte line AML12 and analyzed stably transfected clones which expressed physiological amounts of HBx. P53 was induced by UV irradiation.RESULTS： The p53 induction by UV irradiation was unaffected by stable expression of HBx. However, the expression of the cyclin kinase inhibitor p21^waf/cip/sdi which gets activated by p53 was affected in the HBx transformed cell line AML12-HBx9, but not in HepG2. In AML-HBx9 cells, p21^waf/ciP/sdi -protein expression and p21^waf/dip/sdi transcription were deregulated. Furthermore, the process of apoptosis was affected in opposite ways in the two cell lines investigated. While stable expression of HBx enhanced apoptosis induced by UV irradiation in HepG2-cells, apoptosis was decreased in HBx transformed AML12-HBx9. P53 repressed transcription from the HBV enhancer I, when expressed from expression vectors or after induction of endogenous p53 by UV irradiation. Repression by endogenous p53 was partially reversible by stably expressed HBx in both cell lines.CONCLUSION： Stable expression of HBx leads to deregulation of apoptosis induced by UV irradiation depending on the cell line used. In an immortalized hepatocyte line HBx acted anti-apoptotic whereas expression in a carcinoma derived hepatocyte line HBx enhanced apoptosis.

关键词： Apoptosis Hepatitis B virus Hepatocyte lines

Outcome in neonates with necrotizing enterocolitis and patent ductus arteriosus

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World Journal of Pediatrics 2016年第1期12卷 55-59页

作者： Ulf Kessler Franzisca Schulte Dietmar Cholewa Mathias Nelle stephan C.schaefer Peter M.Klimek Steffen Berger Department of Pediatric Surgery InselspitalBern University Hospital and University of BernSwitzerland Division of Neonatology Department of PediatricsInselspitalBern University Hospital and University of BernSwitzerland Institute of Pathology InselspitalUniversity of BernBernSwitzerland Department of Surgery HFR Fribourg-Cantonal HospitalSwitzerland

Background:There is no agreement of the influence of patent ductus arteriosus(PDA)on outcomes in patients with necrotizing enterocolitis(NEC).In this study,we assessed the infl uence of PDA on NEC ***:A retrospective study of 131 infants with established NEC was ***(death,disease severity,need for surgery,hospitalization duration),as well as multiple clinical parameters were compared between NEC patients with no congenital heart disease(n=102)and those with isolated PDA(n=29).Univariate,multivariate and stepwise logistic regression analyses were ***:Birth weight and gestational age were significantly lower in patients with PDA[median(95%CI):1120 g(1009-1562 g),28.4 wk(27.8-30.5 wk)]than in those without PDA[median(95%CI):1580 g(1593-1905 g),32.4 wk(31.8-33.5 wk);P<0.05].The risk of NEC-attributable fatality was higher in NEC patients with PDA(35%)than in NEC patients without PDA(14%)[univariate odds ratio(OR)=3.3,95%CI:1.8-8.6,P<0.05;multivariate OR=2.4,95%CI:0.82-2.39,P=0.111].Significant independent predictors for nonsurvival within the entire cohort were advanced disease severity stage III(OR=27.9,95%CI:7.4-105,P<0.001)and birth weight below 1100 g(OR=5.7,95%CI:1.7-19.4,P<0.01).Conclusions:In patients with NEC,the presence of PDA is associated with an increased risk of ***,when important differences between the two study groups are controlled,only birth weight and disease severity may independently predict mortality.

关键词： congenital heart disease necrotizing enterocolitis neonatal mortality patent ductus arteriosus

Genotype-dependent activation or repression of HBV enhancer Ⅱ by transcription factor COUP-TF1

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World Journal of Gastroenterology 2006年第37期12卷 6054-6058页

作者： Silke F Fischer Katja Schmidt Nicola Fiedler Dieter Glebe Christian Schüttler Jianguang Sun Wolfram H Gerlich Reinald Repp stephan schaefer Instiut für Medizinische Virologie Justus-Liebig-Universitaet Giessen Germany Zentrum für Kinderheilkunde Justus-Liebig-Universitaet Giessen Klinik für Kinder-und Jugendmedizin Klinikum Fulda Germany Institut for Medizinische Mikrobiologie Immunologie und Hygiene Technische Universitaet München Germany Abteilung für Virologie Universitatt Rostock Germany

AIM: To study the expression of HBV enhancer Ⅱ by transcription factor COUP-TF1. METHODS: In order to study the regulation of HBV variants in the vicinity of the NRRE we cloned luciferase constructs containing the HBV enhancer Ⅱ from variants and from HBV genotypes A and D and cotransfected them together with expression vectors for COUP-TF1 into HepG2 cells. RESULTS: Our fi ndings show that enhancer Ⅱ of HBV genotype A is also repressed by COUP-TF1. In contrast, two different enhancer Ⅱ constructs of HBV genotype D were activated by COUP-TF1. The activation was independent of the NRRE because a natural variant with a deletion of nt 1763-1770 was still activated by COUP- TF1. CONCLUSION: Regulation of transcription of the HBV genome seems to differ among HBV genomes derived from different genotypes. These differences in transcriptional control among HBV genotypes may be the molecular basis for differences in the clinical course among HBV genotypes.

关键词： Hepatitis B virus Hepatitis B virus x protein COUP-TF1 Genotype Enhancer Ⅱ

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一株乙肝病毒的基因组克隆及系统学分析

微生物学杂志 2006年第1期26卷 14-19页

作者：孙建光高俊莲 Zarnekow M. schaefer S. 中国农业科学院农业资源与农业区划研究所 Abteilung Virologie Universitt Rostock Schillingallee 7018055 Rostock Germany

乙型肝炎病毒HBV的基因分型在基础研究和临床治疗中具有重要意义。PCR扩增并克隆了来白蒙古的乙肝病毒HBV199的全长基因组。分析表明HBV199基因组全长为3145bp,属于基因型D。HBV199与乙肝病毒基因型D代表菌株x02496的基因组序列差异为1... 详细信息

乙型肝炎病毒HBV的基因分型在基础研究和临床治疗中具有重要意义。PCR扩增并克隆了来白蒙古的乙肝病毒HBV199的全长基因组。分析表明HBV199基因组全长为3145bp,属于基因型D。HBV199与乙肝病毒基因型D代表菌株x02496的基因组序列差异为1．9％；与参比菌株AF280817和AY161157具有更高的亲缘关系，它们的基因组序列差异分别为1．1％和1．5％。不同于所有其他HBV基因组。HBV199基因组缺失了HBc-ORF处nt2021～nt2057之间的37个碱基。

关键词：乙型肝炎病毒基因组克隆系统学分析蒙古

Development of a web-platform for mining applications

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International Journal of Mining Science and Technology 2018年第1期28卷 95-99页

作者： Christopher Newman Zach Agioutantis Nathaniel schaefer Department of Mining Engineering University of Kentucky

‘‘Web ground control"(web GC) provides users with instantaneous access to mine design applications anywhere, at any time, through a web *** a web-based multiple-tier architecture, users are able to easily access ground control designs, perform on-demand calculations in the field, as well as facilitate project collaborations across multiple users, devices, and operating ***, the web GC platform contains five ground control related design applications previously developed and distributed by the US National Institute of Occupational Safety and Health(NIOSH), that is, analysis of roof bolt stability(ARBS), analysis of longwall pillar stability(ALPS), analysis of retreat mining stability(ARMPS), analysis of retreat mining stability–highwall mining(ARMPS-HWM), and analysis of horizontal stress in mining(AHSM).With respect to design decisions made by the web GC development team, the web GC platform will be able to further integrate future mine design applications providing the mining industry with one of a kind umbrella suite of ground control related software available at ones *** following paper provides a detailed overview on the current state of the web GC platform with discussions ranging from back-end database development and design to the front-end user-platform *** on current progress in platform development as well as beta testing results, the web GC platform is scheduled for release in the fall of 2018.

关键词： Ground control Stability Web application Cloud computing

Variations in net litter nutrient input associated with tree species influence on soil nutrient contents in a subtropical evergreen broad-leaved forest

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Chinese Science Bulletin 2014年第1期59卷 46-53页

作者： Lu Qiao Doug Allen schaefer Xiaoming Zou Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Environmental Studies University of Puerto Rico

The influence of tree species on soils has received much attention,but we know little about either the pattern and underlying mechanisms of net nutrient and carbon inputs under canopy for various tree species or the effects of net nutrient input on soil nutrient *** address these issues,we selected three tree species with distinct leaf sizes and arranged litter traps around the target individuals to test what affected net nutrient and carbon inputs under canopy of target individuals,and how net nutrient inputs influenced soil nutrient *** results showed that net litter manganese(Mn)and lignin inputs were significantly different among these tree species,as well as soil exchangeable potassium(K),available iron(Fe)and available *** results also revealed that the species with the smallest sized leaves may stimulate more net Mn and lignin inputs than the species with the largest sized *** the same time,net nutrient inputs correlated with soil available Fe,while the ratio of lignin to nitrogen of net litter correlated with total phosphorus *** results demonstrated that litter production may be the main factor deciding net nutrient and carbon inputs under different tree species’canopy,which significantly differentiated soil iron’s availability.

关键词：土壤养分含量亚热带常绿阔叶林树种枯落物输入营养养分投入木质素

Effect of micro-dimple patterns on capillary pull-off force and friction force of silicon surface

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Chinese Physics B 2009年第1期18卷 231-237页

作者：张向军董云开刘永合 J.A.schaefer State Key Laboratory of Tribology Tsinghua University Institute of Physics and Center of Micro/nano Technology Technich University of IlmenauPF 100565Germany

A microtribometer is used to measure and compare pull-off forces and friction forces exerted on （a） micro-dimpled silicon surfaces, （b） bare silicon surfaces, and （c） octadecyltrichlorosilane （OTS） treated silicon surfaces at different relative humidity （RH） levels separately. It is found that above a critical RH level, the capillary pull-off force increases abruptly and that the micro-dimple textured surface has a lower critical RH value as well as a higher pull-off force value than the other two surfaces. A micro topography parameter, namely sidewall area ratio, is found to play a major role in controlling the capillary pull-off force. Furthermore, micro-dimpled silicon surface is also proved to be not sensitive to variation in RH level, and can realize a stable and decreased friction coefficient compared with un-textured silicon surfaces. The reservoir-like function of micro dimples is considered to weaken or avoid the breakage effect of liquid bridges at different RH levels, thereby maintaining a stable frictional behaviour.

关键词： micro-dimpled surface capillary pull-off force frictional property relative humidity

Evaluation of strategies for the subsequent use of CO_(2)

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Frontiers of Chemical Science and Engineering 2010年第2期4卷 172-183页

作者： Marc schaefer Frank BEHRENDT Thomas HAMMER Berlin Institute of Technology Institute for Energy Process Engineering and Conversion Technologies for Renewable EnergiesBerlin 10623Germany Siemens AG Corporate TechnologyCT PS 591052 ErlangenGermany

If substantial amounts of CO_(2),which according to actual scenarios may in the future be captured from industrial processes and power generation,shall be utilized effectively,scalable energy efficient technologies will be ***,a survey was performed to assess a large variety of applications utilizing CO_(2) chemically(e.g.,production of synthesis-gas,methanol synthesis),biologically(e.g.,CO_(2) as fertilizer in green houses,production of algae),or physically(enhancement of fossil fuel recovery,use as refrigerant).For each of the processes,material and energy balances were set *** with pure CO_(2) at standard conditions,expenditure for transport and further process specific treatment were *** on these calculations,the avoidance of greenhouse gas emissions by applying the discussed technologies was *** on the currently available technologies,applications for enhanced fossil fuel recovery turn out to be most attractive regarding the potential of utilizing large quantities of CO_(2)(total capacity>1000 Gt CO_(2))and producing significant amounts of marketable products on one hand and having good energy and material balances on the other hand(t_(CO_(2)-emitted)/t_(CO_(2)-utilized)0.34).Biological processes such as CO_(2) fixation using microalgae look attractive as long as energy and CO_(2) balance are ***,the development of effective photobioreactors for growing algae with low requirements for footprint area is a challenge.

关键词： CO_(2) utilization survey energy balances synthesis-gas green houses micro-algae fossil fuel recovery

Analysis of the human Atox 1 homologue in Wilson patients

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World Journal of Gastroenterology 2008年第15期14卷 2383-2387页

作者： Isabel Simon Mark schaefer Jürgen Reichert Wolfgang Stremmel Department of Gastroenterology University of HeidelbergGermany

AIM: To analyze the metallochaperone antioxidant-1 (Atox1) gene sequence in Wilson disease patients. METHODS: Mutation analysis of the four exons of the Atox1 gene including the intron- exon boundaries was performed in 63 Wilson disease patients by direct sequencing. RESULTS: From 63 selected patients no mutations were identified after the entire coding region including the intron- exon boundaries of Atox1 were sequenced. One known polymorphism within the Atox1 gene (5’UTR -99 T>C) in 31 (49%) of the Wilson patients as well as one previously undescribed variation (5’UTR -68 C>T) in 2 of the Wilson patients could be detected. Statistical analyses revealed that the existence of a variation within the Atox1- gene showed a tendency towards an earlier onset of the disease. CONCLUSION: Based on the data of this study, no major role can be attributed to Atox1 in the pathophysiology or clinical variation of Wilson disease.

关键词： Antioxidant-1 Wilson disease Wilson's disease protein Mutation analysis