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Thiazolidinedione treatment inhibits bile duct proliferation and fibrosis in a rat model of chronic cholestasis

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World Journal of Gastroenterology 2005年第32期11卷 4931-4938页

作者： Fabio Marra Raffaella DeFranco Gaia Robino Erica Novo Eva Efsen Sabrina Pastacaldi Elena Zamara Alessandro Vercelli Benedetta Lottini Carlo Spirli Mario Strazzabosco Massimo Pinzani Maurizio Parola dipartimento di Medicina Interna and Center for ResearchTransfer and High Education ‘DENOTHE'University of FlorenceItaly dipartimento di Medicina e Oncologia SperimentaleUniversity of Turin Italy Benedetta LottiniMassimo Pinzani Dipartimento di Medicina Interna and Center for ResearchTransferand High Education ‘DENOTHE'University of FlorenceItaly dipartimento di AnatomiaFarmacologia e Medicina Legale University of TurinItaly Istituto Veneto di Medicina MolecolarePadua Italy

AIM： To investigate the effects of troglitazone （TGZ）, an anti-diabetic drug which activates peroxisome proliferatoractivated receptor-y （PPAR-y）, for liver tissue repair, and the development of ductular reaction, following common bile duct ligation （BDL） in rats. METHODS： Rats were supplemented with TGZ （0.2% w/w in the pelleted food） for i wk before BDL or sham operation. Animals were killed at 1, 2, or 4 wk after surgery. RESULTS： The development of liver fibrosis was reduced in rats receiving TGZ, as indicated by significant decreases of procollagen type I gene expression and liver hydroxyproline levels. Accumulation of a-smooth-muscle actin （SMA）-expressing cells surrounding newly formed bile ducts following BDL, as well as total hepatic levels of SMA were partially inhibited by TGZ treatment, indicating the presence of a reduced number and/or activation of hepatic stellate cells （HSC） and myofibroblasts. Development of the ductular reaction was inhibited by TGZ, as indicated by histochemical evaluation and hepatic activity of γ-glutamyltransferase （GGT）. CONCLUSION： Treatment with thiazolidinedione reduces ductular proliferation and fibrosis in a model of chronic cholestasis, and suggests that limiting cholangiocyte proliferation may contribute to the lower development of scarring in this system.

关键词： Cholangiocytes Ductular reaction PPAR-γ Hepatic stellate cells Myofibroblasts Troglitazone

PROM:A Support for Robust Replication in a distributed Object Environment

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Journal of Computer Science & Technology 1990年第2期5卷 139-155页

作者： A.Corradi L.Leonardi dipartimento di Elettronico Informatica e SistemisticaUniversita' di BOLOGNA viale Risorgimento40136 BOLOGNAItaly

The concept of object can be employed to achieve tolerance to hardware faults in distributed *** by introducing several copies for each object allows a continuous service even in case of *** particular,the paper describes an object model,PROM,which exploits replication by defining sev- eral passive back-up copies for any *** system automatically recovers any failure of a copy in execu- tion by activating a spare copy and restarting it from a previous checkpoint. The aim of the paper is the analysis of the effective support for *** support is organized in structured levels on a distributed *** services that the support should include to guarantee the de- sired replication model are described.

关键词： Communication Manager Server Site Server Object Hardware Fault Replication Object

Complexation of As(Ⅲ)by phosphonate ligands in aqueous fluids:Thermodynamic behavior,chemical binding forms and sequestering abilities

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Journal of Environmental Sciences 2020年第8期32卷 100-110页

作者： Donatella Chillè Donatella Aiello Giuseppa Ida Grasso Ottavia Giuffrè Anna Napoli Carmelo Sgarlata Claudia Foti dipartimento di Scienze Chimiche BiologicheFarmaceutiche ed AmbientaliUniversitàdi MessinaViale F.Stagno d’Alcontres 3198166 MessinaItaly dipartimento di Chimica e Tecnologie Chimiche Universitàdella CalabriaVia P.Bucci87036 Arcavacata di Rende(CS)Italy dipartimento di Scienze Chimiche Universitàdegli Studi di CataniaViale A.Doria 695125 CataniaItaly

In recent years,the contamination of water by arsenic reached alarming levels in many countries of the world,attracting the interest of many researchers engaged in testing methodologies able to remove this harmful *** important aspect that must be taken into consideration is the possibility to find arsenic in different chemical forms which could require different approaches for its *** this aim,a speciation analysis appears to be crucial for better understanding the behavior of arsenic species in aqueous solutions,especially in presence of compounds with marked chelating *** can be identified as good sequestering agents and,at this purpose,this manuscript intends to investigate the interaction of As(Ⅲ)with three phosphonic acids derived from nitrilotriacetic acid(NTA)by replacements of one(N-(Phosphonomethyl)iminodiacetic acid,NTAP),two(N,N-Bis-(phosphonomethyl)glycine,NTA2P)and three(Nitrilotri(methylphosphonic acid),NTA3P)carboxylic groups with the same number of phosphonate *** in-depth potentiometric and calorimetric investigation allowed to determine speciation models featured by simple ML,MLH i and ML(OH)species.A complete thermodynamic characterization of the systems is reported together with the definition of coordination mode by mass spectrometry *** the light of the speciation models,the possibility of using these ligands in arsenic removal techniques was assessed by determining the pL 0.5(the concentration of ligand able to remove the 50%of metal ion present in trace).All ligands show a good sequestering ability,in particular under the conditions of fresh water,following the trend NTA3P>NTA2P>NTAP.

关键词： Phosphonate ligands Arsenic Thermodynamic interaction parameters Sequestering ability

Comparison of smart panels for tonal and broadband vibration and sound transmission active control

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International Journal of Smart and Nano Materials 2020年第4期11卷 431-484页

作者： Paolo Gardonio Emanuele Turco Loris Dal Bo dipartimento Politecnico di Ingegneria E Architettura UniversitàDegli Studi Di UdineUdineItaly

This paper presents a comprehensive overview of the principal features of smart panels equipped with feed-forward and feedback systems for the control of the flexural response and sound transmission due respectively to tonal and to stochastic broadband *** smart panels are equipped with two types of actuators:first,distributed piezoelectric actuators formed either by small piezoelectric patches or large piezoelectric films bonded on the panels and second,point actuators formed by proof-mass electromagnetic ***,the panels encompass three types of sensors:first,small capacitive microphone sensors placed in front of the panels;second,distributed piezoelectric sensors formed by large piezoelectric films bonded on the panels and third point sensors formed by miniaturized *** proposed systems implement both single-channel and multi-channel feed-forward and feedback control *** study shows that,the vibration and sound radiation control performance of both feed-forward and feedback systems critically depends on the sensor-actuator configurations.

关键词： Active structural acoustic control active vibration control feed-forward control feedback control piezoelectric transducers proof-mass electromagnetic actuators

Evidence for a con served microbiota across the different developmental stages of Plodia interpunctella

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Insect Science 2019年第3期26卷 466-478页

作者： Valeria Mereghetti Bessem Chouaia Lidia Limonta Daria Patrizia Locatelli Matteo Montagna dipartimento di Scienze Agrarie e Ambientali Universita degli Studi di Milano Milan Italy dipartimento di Scienze per gli Alimenti la Nutrizione I'Ambiente Universita degli Studi di Milano Milan Italy

diversity and composition of lepidopteran microbiotas are poorly investigated, especially across the different developmental stages. To improve this knowledge, we characterize the microbiota among different developmental stages of the Indian meal moth, Plodia interpunctella, which is considered one of the major pest of commodities world-wide. Using culture-independent approach based on Illumina 16S rRNA gene sequencing we characterized the microbiota of four developmental stages: eggs, first-, and last-instar larvae, and adult. A total of 1022 bacterial OTUs were obtained, showing a quite diversified microbiota associated to all the analyzed stages. The microbiotas associated with P. interpunctella resulted almost constant throughout the developmental stages, with approximately 77% of bacterial OTUs belonging to the phylum of Proteobacteria. The dominant bacterial genus is represented by Burkholderia (?64%), followed by Propionibacterium, Delftia, Pseudomonas, and Stenotrophomonas. A core bacterial community, composed of 139 OTUs, was detected in all the developmental stages, among which 112 OTUs were assigned to the genus Burkholderia. A phylogenetic reconstruction, based on the 16S rRNA, revealed that our Burkholderia OTUs clustered with Burkholderia cepacia complex, in the same group of those isolated from the hemipterans Gossyparia spuria and Acanthococcus aceris. The functional profiling, predicted on the base of the bacterial 16S rRNA, indicates differences in the metabolic pathways related to metabolism of amino acids between preimaginal and adult stages. We can hypothesize that bacteria may support the insect host during preimaginal stages.

关键词： Burkholderia Illumina sequencing Indian meal moth insect symbiosis Proteobacteria

Trajectory Attractors for Binary Fluid Mixtures in 3D

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Chinese Annals of Mathematics,Series B 2010年第5期31卷 655-678页

作者： Ciprian G.GAL Maurizio GRASSELLI Department of Mathematics University of Missouri dipartimento di Matematica "F. Brioschi" Politecnico di Milano

Two different models for the evolution of incompressible binary fluid mixtures in a three-dimensional bounded domain are *** consist of the 3D incompressible Navier-Stokes equations,subject to time-dependent external forces and coupled with either a convective Allen-Cahn or Cahn-Hilliard *** systems can be viewed as generalizations of the Navier-Stokes equations to two-phase *** the trajectory approach,the authors prove the existence of the trajectory attractor for both systems.

关键词： Navier-Stokes equations Allen-Cahn equations Cahn-Hilliard equations Two-phase fluid flows Longtime behavior Trajectory attractors

Mechanisms underlying lineage commitment and plasticity of human yo T cells

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Cellular & Molecular Immunology 2013年第1期10卷 30-34页

作者： Nadia Caccamo Matilde Todaro Guido Sireci Serena Meraviglia Giorgio Stassi Francesco dieli dipartimento di Biopatologia e Biotecnologie Mediche e Forensi Universita degli Studi di Palermo Palermo Italy dipartimento di discipline Chirurgiche ed Oncologiche Universita degli Studi di Palermo Palermo: Italy

Phenotypic and functional heterogeneity are the hallmarks of effector and memory T cells. Upon antigen stimulation, y T cells differentiate into two major types of memory T cells： central memory cells, which patrol the blood and secondary lymphoid organs, and effector memory cells, which migrate to peripheral tissues, y T cells display in vitroa certain degree of plasticity in their function that is reminiscent of that which is observed in conventional CD4 T cells. Similar to CD4 T cells, in which a plethora of specialized subsets affect the host response, y8 T cells may readily and rapidly assume distinct Thl-, Th2-, Th17-, TFH and T regulatory-like effector functions, suggesting that they profoundly influence cell-mediated and humoral immune responses. In addition to differences in cytokine repertoire, y~ T cells exhibit diversity in homing, such as migration to lymph node follicles, to help B cells versus migration to inflamed tissues. Here, we review our current understanding of y T-cell lineage heterogeneity and flexibility, with an emphasis on the human system, and propose a classification of effector y T cells based on distinct functional phenotypes.

关键词： cytokines effector and memory cells y T cells lineage-specifying factors T-cell subsets

Schwann cell development,maturation and regeneration：a focus on classic and emerging intracellular signaling pathways

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Neural Regeneration Research 2017年第7期12卷 1013-1023页

作者： Luca Franco Castelnovo Veronica Bonalume Simona Melfi Marinella Ballabio Deborah Colleoni Valerio Magnaghi dipartimento di Scienze Farmacologiche e Biomolecolari Universita degli Studi di Milano Milan Italy

The development,maturation and regeneration of Schwann cells（SCs）,the main glial cells of the peripheral nervous system,require the coordinate and complementary interaction among several factors,signals and intracellular *** regulatory molecules consist of integrins,neuregulins,growth factors,hormones,neurotransmitters,as well as entire intracellular pathways including protein-kinase A,C,Akt,Erk/MAPK,Hippo,mTOR,*** instance,Hippo pathway is overall involved in proliferation,apoptosis,regeneration and organ size control,being crucial in cancer proliferation *** SCs,Hippo is linked to merlin and YAP/TAZ signaling and it seems to respond to mechanic/physical ***,among factors regulating SCs,also the signaling intermediates Src tyrosine kinase and focal adhesion kinase（FAK）proved relevant for SC fate,participating in the regulation of adhesion,motility,migration and in vitro *** SCs,the factors Src and FAK are regulated by the neuroactive steroid allopregnanolone,thus corroborating the importance of this steroid in the control of SC *** this review,we illustrate some old and novel signaling pathways modulating SC biology and functions during the different developmental,mature and regenerative states

关键词： myelin neuroactive steroids electromagnetic field peripheral nervous system

REDUCED BASIS METHOD FOR PARAMETRIZED ELLIPTIC ADVECTION-REACTION PROBLEMS

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Journal of Computational Mathematics 2010年第1期28卷 122-148页

作者： Luca Dedè MOX-Modeling■Scientific Computing Dipartimento di Matematica"F.Brioschi"Politecnico di Milano

In this work we consider the Reduced Basis method for the solution of parametrized advection-reaction partial differential equations. For the generation of the basis we adopt a stabilized finite element method and we define the Reduced Basis method in the ＂primal- dual＂ formulation for this stabilized problem. We provide a priori Reduced Basis error estimates and we discuss the effects of the finite element approximation on the Reduced Basis error. We propose an adaptive algorithm, based on the a posteriori Reduced Basis error estimate, for the selection of the sample sets upon which the basis are built; the idea leading this algorithm is the minimization of the computational costs associated with the solution of the Reduced Basis problem. Numerical tests demonstrate the efficiency, in terms of computational costs, of the ＂primal-dual＂ Reduced Basis approach with respect to an ＂only primal＂ one. Parametrized advection-reaction partial differential equations, Reduced Basis method, ＂primal-dual＂ reduced basis approach, Stabilized finite element method, a posteriori error estimation.

关键词： Parametrized advection-reaction partial differential equations Reduced Basis method "primal-dual" reduced basis approach Stabilized finite element method a posteriori error estimation.