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Dual Targeting to Mitochondria and Chloroplasts： Characterization of Thr-tRNA Synthetase Targeting Peptide

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Molecular Plant 2009年第6期2卷 1298-1309页

作者： Anna-Karin Berglund erika Spanning Henrik Biverstahl Gianluca Maddalo Christian Tellgren-Roth Lena Maler Elzbieta Glaser Department of Biochemistry and Biophysics Arrhenius Laboratories for Natural Science Stockholm University SF-10691 Stockholm Sweden Department of Genetics and Pathology Rudbecklaboratoriet Uppsala University SE-751 85 Uppsala Sweden

There is a group of proteins that are encoded by a single gene, expressed as a single precursor protein and dually targeted to both mitochondria and chloroplasts using an ambiguous targeting peptide. Sequence analysis of 43 dual targeted proteins in comparison with 385 mitochondrial proteins and 567 chloroplast proteins ofArabidopsis thaliana revealed an overall significant increase in phenylalanines, leucines, and serines and a decrease in acidic amino acids and glycine in dual targeting peptides （dTPs）. The N-terminal portion of dTPs has significantly more serines than mTPs. The number of arginines is similar to those in mTPs, but almost twice as high as those in cTPs. We have investigated targeting determinants of the dual targeting peptide of Thr-tRNA synthetase （ThrRS-dTP） studying organellar import of N- and C-terminal deletion constructs of ThrRS-dTP coupled to GFR These results show that the 23 amino acid long N-terminal portion of ThrRS-dTP is crucial but not sufficient for the organellar import. The C-terminal deletions revealed that the shortest peptide that was capable of conferring dual targeting was 60 amino acids long. We have purified the ThrRS- dTP（2-60） to homogeneity after its expression as a fusion construct with GST followed by CNBr cleavage and ion exchange chromatography. The purified ThrRS-dTP（2-60） inhibited import of pF1β into mitochondria and of pSSU into chloroplasts at μM concentrations showing that dual and organelle-specific proteins use the same organellar import pathways. Furthermore, the CD spectra of ThrRS-dTP（2-60） indicated that the peptide has the propensity for forming α-helical structure in membrane mimetic environments; however, the membrane charge was not important for the amount of induced helical structure. This is the first study in which a dual targeting peptide has been purified and investigated by biochemical and biophysical means.

关键词： Dual targeting mitochondria chloroplast targeting peptide aminoacyl-tRNA synthetase

Structural and mechanical properties of La_(1/3)NbO_3 and La_(1/3)TaO_3 thin films prepared by chemical solution deposition

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Journal of Rare Earths 2017年第11期35卷 1115-1125页

作者： Helena Brunckova Lubomir Medvecky Alexandra Kovalcikova Martin Fides erika Mudra Juraj Durisin Martin Sebek Maria Kanuchova Jiri Skvarla Institute of Materials Research Slovak Academy of Sciences Watsonova 47040O1 Kosice Slovakia Technical "University of Kosice BERG Faculty Letna 9 04200 Kosice SIovakia

In this work, properties of perovskite lanthanum niobate La1/3NbO3(LN) and tantalate La1/3TaO3(LT)transparent thin films(200 nm thickness) prepared by chemical solution deposition on Pt/SiO2/Si substrates were described. The precursors and films were analyzed using FTIR and XPS spectra, XRD and SEM imaging. The both films after annealing at 1100 ℃ contained perovskite phase with a small fraction of pyrochlore LaNb5O14(in LN). The heterogeneous micro structure of LN film was composed from spherical or needle-like particles and homogeneous LT film that resulted in significant changes of their mechanical properties. The elastic modulus and hardness of these films were characterized for the first time by conventional and continuous stiffness(CSM) nanoindentation. The LT film modulus(E) and hardness(H) were higher(105.7 and 5.3 GPa) than LN(91.5 and 3.8 GPa). The effect of microstructure on mechanical properties is significant. In addition, the average Derjaguin-Muller-Toporov(DMT)-based elastic modulus of LN film surface were estimated50 GPa using AFM PeakForce QNM elastic mapping. The findings presented here can contribute to the fabrication of LN and LT films for the application to electrolytic thin film devices.

关键词： Thin films Sol-gel Perovskites Microstructures Mechanical properties

Naringenin prevents experimental liver fibrosis by blocking TGFβ-Smad3 and JNK-Smad3 pathways

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World Journal of Gastroenterology 2017年第24期23卷 4354-4368页

作者： erika Hernández-Aquino Natanael Zarco Sael Casas-Grajales erika Ramos-Tovar Rosa E Flores-Beltrán Jonathan Arauz Mineko Shibayama Liliana Favari Víctor Tsutsumi José Segovia Pablo Muriel Laboratory of Experimental Hepatology Department of PharmacologyCinvestav-IPNApartado Postal 14-740Mexico City Department of Physiology Biophysics and NeurosciencesCinvestav-IPNApartado Postal 14-740Mexico City Department of Pharmacology School of MedicineAutonomous University of Baja CaliforniaMexicaliApartado Postal 21100 Department of Infectomics and Molecular Pathogenesis Cinvestav-IPNApartado Postal 14-740Mexico City

To study the molecular mechanisms involved in the hepatoprotective effects of naringenin (NAR) on carbon tetrachloride (CCl4)-induced liver fibrosis. METHODSThirty-two male Wistar rats (120-150 g) were randomly divided into four groups: (1) a control group (n = 8) that received 0.7% carboxy methyl-cellulose (NAR vehicle) 1 mL/daily p.o.; (2) a CCl4 group (n = 8) that received 400 mg of CCl4/kg body weight i.p. 3 times a week for 8 wk; (3) a CCl4 + NAR (n = 8) group that received 400 mg of CCl4/kg body weight i.p. 3 times a week for 8 wk and 100 mg of NAR/kg body weight daily for 8 wk p.o.; and (4) an NAR group (n = 8) that received 100 mg of NAR/kg body weight daily for 8 wk p.o. After the experimental period, animals were sacrificed under ketamine and xylazine anesthesia. Liver damage markers such as alanine aminotransferase (ALT), alkaline phosphatase (AP), γ-glutamyl transpeptidase (γ-GTP), reduced glutathione (GSH), glycogen content, lipid peroxidation (LPO) and collagen content were measured. The enzymatic activity of glutathione peroxidase (GPx) was assessed. Liver histopathology was performed utilizing Masson’s trichrome and hematoxylin-eosin stains. Zymography assays for MMP-9 and MMP-2 were carried out. Hepatic TGF-β, α-SMA, CTGF, Col-I, MMP-13, NF-κB, IL-1, IL-10, Smad7, Smad3, pSmad3 and pJNK proteins were detected via western blot. RESULTSNAR administration prevented increases in ALT, AP, γ-GTP, and GPx enzymatic activity; depletion of GSH and glycogen; and increases in LPO and collagen produced by chronic CCl4 intoxication (P 4. Although zymography assays showed that CCl4 produced an increase in MMP-9 and MMP-2 gelatinase activity; interestingly, NAR administration was associated with normal MMP-9 and MMP-2 activity (P < 0.05). The anti-inflammatory, antine

关键词： Fibrosis Transforming growth factor-β Naringenin pSmad3 Smad3 JNK Nuclear factor kappa Carbon tetrachloride

Hyperplasia vs hypertrophy in tissue regeneration after extensive liver resection

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World Journal of Gastroenterology 2017年第10期23卷 1764-1770页

作者： Fabio Marongiu Michela Marongiu Antonella Contini Monica Serra erika Cadoni Riccardo Murgia Ezio Laconi Experimental Medicine Unit Department of Biomedical SciencesUniversity of Cagliari09124 CagliariItaly

To address to what extent hypertrophy and hyperplasia contribute to liver mass restoration after major tissue *** ability of the liver to regenerate is remarkable on both clinical and biological grounds. Basic mechanisms underlying this process have been intensively investigated. However, it is still debated to what extent hypertrophy and hyperplasia contribute to liver mass restoration after major tissue loss. We addressed this issue using a genetically tagged system. We were able to follow the fate of single transplanted hepatocytes during the regenerative response elicited by 2/3 partial surgical hepatectomy (PH) in rats. Clusters of transplanted cells were 3D reconstructed and their size distribution was evaluated over time after *** size and liver DNA content were largely recovered 10 d post-PH, as expected (e.g., total DNA/liver/100 g b.w. was 6.37 ± 0.21 before PH and returned to 6.10 ± 0.36 10 d after PH). Data indicated that about 2/3 of the original residual hepatocytes entered S-phase in response to PH. Analysis of cluster size distribution at 24, 48, 96 h and 10 d after PH revealed that about half of the remnant hepatocytes completed at least 2 cell cycles. Average size of hepatocytes increased at 24 h (248.50 μm2 ± 7.82 μm2, P = 0.0015), but returned to control values throughout the regenerative process (up to 10 d post-PH, 197.9 μm2 ± 6.44 μm2, P = 0.11). A sizeable fraction of the remnant hepatocyte population does not participate actively in tissue mass *** stands as the major mechanism contributing to liver mass restoration after PH, with hypertrophy playing a transient role in the process.

关键词： Liver regeneration Hypertrophy Hyperplasia

Conflicting Emotions： Globalization and Decoloniality in Tambien la lluvia

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Journal of Philosophy Study 2016年第5期6卷 275-281页

作者： erika Bondi Arizona State University

It is not difficult to understand the success of Tambien la lluvia （2010） starring the internationally recognized Mexican actor Gael Garcia Bernal. The coproduction among France, Spain, and Mexico succeeds in creating film that gains critical as well as commercial attention for its treatment of the theme of globalization as well as for its aesthetic quality. The Spanish director, Icfar Boallafn heavily employs metacinematography, metanarrative, and intertextuality in the film but loses subtlety in conveying the message of globalization as a continuation of colonization. As the study of the aforementioned themes has been exhausted, this analysis focuses on the role and representation of the emotions that are shaped by the global economic circumstance of capitalism, consumerism, and globalization. I will analyze and compare the emotions of the western characters with that of the indigenous characters in Bolivia to demonstrate how the filmic representations of emotions are influenced by the understanding of history, culture, and society. This analysis attempts to reveal how the western subjects struggle to locate their emotions resulting in their displacement in representations of information and simulations of reality that have lost their connection with the original referent. On the other hand, the indigenous＇ emotional repertoire is based on their direct interaction with the land and their community. Furthermore, the first people appear to have inherited and cultivated their emotions as a community, which motivate them to act collectively to continue their incessant struggle against exploitation and colonization. Through this study, I hope to explore the relationship between the emotions and decoloniality by identifying how cultivation of emotions could have a major impact in questioning the Eurocentric episteme imposed onto the periphery.

关键词： decoloniality emotions emotionology postemotionalism latin American film

Z-line examination by the PillCam^(TM) SB:Prospective comparison of three ingestion protocols

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World Journal of Gastroenterology 2010年第1期16卷 63-68页

作者： Ignacio Fernandez-Urien erika Borobio Inmaculada Elizalde Rebeca Irisarri Juan Jose Vila Jesus Maria Urman Javier Jimenez Department of Gastroenterology Hospital of Navarra

AIM:To evaluate the Z-line visualization by the PillCamTM SB2 using three different ingestion protocols. METHODS:Ninety consecutive patients undergoing small bowel capsule endoscopy(SBCE)between January and May 2008 were included in the study. They swallowed the capsule in the standing(Group A= 30),supine(Group B=30)and right supine positions (Group C=30).Baseline patient characteristics, difficulties in capsule ingestion,esophageal transit times(ETT)and Z-line visualization were noted. RESULTS:No significant differences were found between the groups with regard to baseline patient characteristics,ingestion difficulties and complete SB examinations(P>0.05).At least 1 frame of the Z-line was detected in 15.8%,46.7%and 90%of patients in groups A,B and C,respectively(P<0.001).The average number of Z-line images was 0.21±0.53,3.23 ±6.59 and 5.53±7.55 and the mean%of the Z-linedetected was 71.3,25.1 and 8.3,in groups A,B and C, respectively(both P<0.001).ETT times were longer in the supine group followed by the right supine and the standing groups(median of 237 s vs 64 s and 39 s, respectively;P<0.001). CONCLUSION:Z-line visualization in patients undergoing SBCE can be accurately achieved in most cases when the capsule is swallowed in the right supine position.

关键词： Barrett Capsule endoscopy Esophagus Gastroesophageal reflux disease Ingestion Varices Z-line

Micropropagation of Eucalyptus grandis×*** AEC 224 clone

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Journal of Forestry Research 2017年第1期28卷 29-39页

作者： Cassiana de Oliveira Juliana Degenhardt-Goldbach Gisela Manuela de Franca Bettencourt erika Amano Luziane Franciscon Marguerite Quoirin Department of Plant Science Federal University of Parana1540Rua dos FuneionariosCuritibaParanaBrazil Embrapa-Forest 111Estrada da RibeiraColomboParanaBrazil Department of Technology Federal University of Parana210avenida CelFrancisco Heraiclito dos SantosCuritibaParanaBrazil Department of Botany Federal University of Parana210avenida CelFrancisco Heraiclito dos SantosCuritibaParanaBrazil

Genetic transformation systems require protocols that allow regenerating transgenic plants from transformed tissues. This study aimed to establish a protocol for indirect organogenesis in leaf explants of a Eucalyptus grandis x E. urophylla AEC 224 clone. During callogenesis stage, several concentrations of NAA and then NAA or 2,4-D combined with TDZ were tested in JADS culture medium for 30 days, followed by subculture of the explants in the regeneration medium, containing 5.0 μM BA and 0.5 μM NAA for another 30 days. In these media, the explant oxidation rate was high （95 %）. Thus, in order to reduce oxidation, different ;culture media were compared： WPM, MS, JADS and modified QL, followed by explant transfer onto regeneration medium. The highest percentage of regeneration and the lowest oxidation rate were achieved on WPM medium. Then, NAA and 2,4-D were tested in combination with TDZ and also TDZ and BA combined with NAA in WPM medium. The most efficient culture media in terms of shoot regeneration were WPM supplemented with 0.25 μM TDZ and 0.1μM NAA during 30 days for callus induction and then with 5.0 μM BA and 0.5 μM NAA for another 30 days. This protocol yielded a regeneration rate of 43 %, with a low oxidation of tissues. A rooting experiment was conducted using half strength MS medium and comparing three concentrations of IBA （2.46, 4.90 and 7.35μM）. The highest rooting percentage （35 %） was obtained on medium containing 2.46μM IBA. Once the shoots were rooted, acclimatization in a greenhouse was not challenging and plant survival reached 100 %.

关键词： Callogenesis Eucalyptus urograndis Organogenesis WPM culture medium

Immunologic, metabolic and genetic factors in hepatitis C virus infection

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World Journal of Gastroenterology 2014年第13期20卷 3443-3456页

作者： Nora A Fierro Karina Gonzalez-Aldaco Rafael Torres-Valadez erika Martinez-Lopez Sonia Roman Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara"Fray Antonio Alcalde" and Health Sciences CenterUniversity of GuadalajaraGuadalajara 44280JaliscoMexico

The mechanisms that regulate disease progression during hepatitis C virus(HCV)infection and the response to treatment are not clearly *** studies have demonstrated that a strong host immune response against HCV favors HCV *** addition,genetic factors and metabolic machinery,particularly cholesterol modulation,are involved in HCV *** is likely that the interplay between all of these factors contributes to the outcome of HCV *** recent years,the world has experienced its largest epidemic of *** and the United States are the leading sufferers from this epidemic at the global *** is associated with the development ofnumerous pathologies including hypercholesterolemia which is one of the eight most important risk factors for mortality in *** may be related to the course of HCV infection in this ***,we focus on the urgent need to study the progression of HCV infection in relation to ethnic *** are discussed that hold promise in identifying immune,metabolic and genetic factors that,in conjunction,could be therapeutic targets or predictors of the progression of HCV infection.

关键词： Hepatitis C virus Immune response Lipids Metabolism Genetics

Geopoetical Analysis of Livonia During The Great Northern War Based on The Last Novik A Historical Novel by Ivan Lazhechnikov

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Journal of Literature and Art Studies 2018年第3期8卷 378-383页

作者： erika Kuzmina Warsaw University Warsaw Poland

The term geopoetics has a wide interpretation. It is defined as a project of the cultural activity aimed at creating and changing territorial myths and research path, which considers the interaction between literary creativity and geographical space. Defining this term, it is possible to introduce a geopoetical analysis diagram based on three interconnected positions： the writer＇s personality, the universe of an artwork and its characters. The Last Novik--A historical novel by Lazhechnikov analysis example presented on a diagram reveals the relationship between time and space in the literary work, as well as the author＇s interaction with the described events.

关键词： geopoetic The Great Northern War Livonia The Last Novik