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World Journal of Gastroenterology 2005年第40期11卷 6243-6248页

作者： Anton Oertl Jens Castein tobias Engl Wolf-Dietrich Beecken Dietger Jonas Richard Melamed Roman A. Blaheta Zentrum der Chirurgie

AIM To study adhesion capacity and CD44 expression of human gastric adenocarcinoma MKN45 cells at different stages of a first cell cycle. METHODS MKN45 cells were synchronized by aphidicolin and assayed for adhesion to an endothelial cell （HUVEC） monolayer. Surface expression of CD44 and CD44 splice variants on MKN45 cells was evaluated by flow cytometry. Functional relevance of CD44 adhesion receptors was investigated by blocldng studies using anti CD44 monodonal antibodies or by hyaluronan digestion. RESULTS： Adhesion of MKN45 to HUVEC was increased during G2/M transit, after which adhesion returned to baseline levels with cell cycle completion. In parallel, CD44 splice vadants CD44v4, CD44v5, and CD44v7 were all upregulated on MKN45 during cell cycle progression with a maximum effect in G2/M. The function of CD44 surface receptors was assessed with specific receptor blocking monoclonal antibodies or removal of hyaluronan by digestion with hyaluronidase. Both strategies inhibited tumor cell adhesion to HUVEC by nearly 50%, which indicates that MKN45-HUVEC-interaction is CD44 dependent. CONCLUSION CD44 expression level is linked to the cell cycle in gastrointestinal tumor cells, which in turn leads to cell cycle dependent alterations of their adhesion behaviour to endothelium.

关键词： Cell cycle CD44 Adhesion Gastrointestinal tumors

Assessing the Storage Root Development of Cassava with a New Analysis Tool

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Plant Phenomics 2022年第1期4卷 43-57页

作者： Jens Wilhelm tobias Wojciechowski Johannes A.Postma Dirk Jollet Kathrin Heinz Vera Bockem Mark Muller-Linow Institute of Plant Sciences IBG-2Forschungszentrum Julich GmbH52425 JulichGermany Tesla Automation GmbH 54595 PrumGermany

Storage roots of cassava plants crops are one of the main providers of starch in many South American,African,and Asian *** varieties with high yields is crucial for growing and *** requires a better understanding of the dynamics of storage root formation,which is usually done by repeated manual evaluation of root types,diameters,and their distribution in excavated *** introduce a newly developed method that is capable to analyze the distribution of root diameters automatically,even if root systems display strong variations in root widths and clustering in high *** application study was conducted with cassava roots imaged in a video acquisition *** root diameter distribution was quantified automatically using an iterative ridge detection approach,which can cope with a wide span of root diameters and *** approach was validated with virtual root models of known geometries and then tested with a time-series of excavated root *** on the retrieved diameter classes,we show plausibly that the dynamics of root type formation can be monitored qualitatively and *** conclude that this new method reliably determines important phenotypic traits from storage root crop *** method is fast and robustly analyses complex root systems and thereby applicable in high-throughput phenotyping and future breeding.

关键词： crops roots Storage

A Study of Shark Stealth Behavior in the Proximity of Divers

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Open Journal of Animal Sciences 2015年第2期5卷 224-228页

作者： Erich ritter Raid Amin Department of Mathematics and Statistics University of West Florida Pensacola USA Shark Research Institute Florida Office Pensacola USA

This study examines the approach patterns of sharks in the vicinity of human divers, focusing on the diver’s body orientation and a shark’s distance from the sea bed when approaching the diver. A standardized video method was used to record the scenario of diver(s) kneeling in the sand while being approached by sharks. This showed that sharks had a preference to move in from outside a diver’s field of vision while larger sharks stayed closer to the sea floor. This may simultaneously enhance camouflage while reducing potential escape routes for the approaching animal. This stealth behavior raises the question of how sharks may interpret humans when moving towards them.

关键词： Blind Spot Camouflage Escape Routes Shark Stealth

Multi-scale approach to understanding climate effects on offspring size at birth and date of birth in a reptile

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Integrative Zoology 2010年第2期5卷 164-175页

作者： ChloéD.CADBY Geoffrey M.WHILE Alistair J.HOBDAY tobias ULLER Erik WAPSTRA School of Zoology University of Tasmania Climate Adaptation Flagship CSIRO Marine and Atmospheric ResearchHobartAustralia Edward Grey Institute Department of ZoologyUniversity of OxfordUK

Climate change is already impacting species around the *** most focus has been on the effect of temperature,changes in climatic variables other than temperature are also expected to drive biological *** models suggest that ectotherms,such as reptiles,will be strongly affected by climate change;however,data from natural populations are ***,we use extensive data from 2 populations of a viviparous lizard(Niveoscincus ocellatus Gray,1845)at the climatic extreme of the species *** examine the effects of climate at a local,a regional and a global scale(thus,integrating a suite of variables at different spatial and temporal scales)on 2 key life history traits:offspring date of birth and size at ***,our results show that across 9 years of study,local temperature had strong effects on the offspring date of birth but not on the size at ***,a rapid increase in local temperature throughout the species range(as predicted under global warming scenarios)is likely to affect phenological processes with potential concomitant effects on offspring fitness and survival.

关键词： atmospheric index climate change lizard phenology sea surface temperature

Turning to myelin turnover

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Neural Regeneration Research 2019年第12期14卷 2063-2066页

作者： tobias J.Buscham Maria A.Eichel Sophie B.Siems Hauke B.Werner Department of Neurogenetics Max Planck Institute of Experimental Medicine

Neural plasticity in the adult central nervous system involves the adaptation of myelination, including the formation of novel myelin sheaths by adult-born oligodendrocytes. Yet, mature oligodendrocytes slowly but constantly turn over their pre-existing myelin sheaths, thereby establishing an equilibrium of replenishment and degradation that may also be subject to adaptation with consequences for nerve conduction velocity. In this short review we highlight selected approaches to the normal turnover of adult myelin in vivo, from injecting radioactive precursors of myelin constituents in the 1960s to current strategies involving isotope labeling and tamoxifen-induced gene targeting.

关键词： oligodendrocyte myelin plasticity and turnover degradation tamoxifen metabolic labeling isotope labeling neural plasticity myelinoid bodies central nervous system

Dietary arachidonate in milk replacer triggers dual benefits of PGE2 signaling in LPS-challenged piglet alveolar macrophages

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Journal of Animal Science and Biotechnology 2019年第2期10卷 435-448页

作者： Kathleen R.Walter Xi Lin Sheila K.Jacobi tobias Kaser Debora Esposito Jack Odle Department of Animal Science Plants for Human Health InstituteNorth Carolina State UniversityKannapolisNorth CarolinaUSA Department of Animal Science North Carolina State UniversityRaleighNorth CarolinaUSA Department of Animal Science Ohio State UniversityColumbusOhioUSA Department of Population Health and Pathobiology College of Veterinary MedicineNorth Carolina State UniversityRaleighNorth CarolinaUSA.

Background: Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits ***: Day-old pigs(n = 60) were allotted to one of three dietary groups for 21 d(n = 20/diet), and received either a control diet(CON, arachidonate = 0.5% of total fatty acids), an arachidonate(ARA)-enriched diet(LC n-6,ARA = 2.2%), or an eicosapentaenoic(EPA)-enriched diet(LC n-3, EPA = 3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24 h, and m RNA was isolated to assess markers associated with inflammation and eicosanoid *** media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1)oxygen consumption and extracellular acidification(via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24 h of LPS ***: Concentration of ARA(% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3(P < 0.01). Following LPS stimulation, abundance of COX-2 and TNF-α mRNA(P < 0.0001), and PGE2 secretion(P < 0. 01) were higher in LC n-6 PAM vs. CON. However, ALOX5 abundance was1.6-fold lower than CON. Macrophages from CON and LC n-6 groups were 4-fold higher in ALOX12/15 abundance(P < 0.0001) compared to LC n-3. Oxygen consumption and extracellular acidification rates increased over 4 h following LPS stimulation(P < 0.05) regardless of treatment. Similarly, increases in cytoplasmic oxidation(P < 0.001)and nitric oxide production(P < 0.002) were observed after 18 h of LPS stimulation but were unaffected by ***: We infer that enriching diets with arachidonic acid may be an ef

关键词： Arachidonic acid Cyclooxygenase Eicosanoid Eicosapentaenoic acid Inflammation Lipid mediator class switch LPS Lipoxin Porcine alveolar macrophage

Enhancing 3D Reconstruction Accuracy of FIB Tomography Data Using Multi‑voltage Images and Multimodal Machine Learning

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Nanomanufacturing and Metrology 2024年第1期7卷 48-60页

作者： Trushal Sardhara Alexander Shkurmanov Yong Li Lukas Riedel Shan Shi Christian J.Cyron Roland C.Aydin Martin ritter Institute for Continuum and Material Mechanics Hamburg University of TechnologyHamburgGermany Electron Microscopy Unit Hamburg University of TechnologyHamburgGermany Institute of Materials Physics and Technology Hamburg University of TechnologyHamburgGermany Institute of Materials Mechanics Helmholtz-Zentrum HereonGeesthachtGermany Research Group of Integrated Metallic Nanomaterials Systems Hamburg University of TechnologyHamburgGermany Institute of Material Systems Modeling Helmholtz-Zentrum HereonGeesthachtGermany

FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of *** approach involves collecting in-plane SEM imagesand using FIB to remove material layers for imaging subsequent planes,thereby producing image ***,theseimage stacks in FIB-SEM tomography are subject to the shine-through effect,which makes structures visible from theposterior regions of the current *** artifact introduces an ambiguity between image intensity and structures in thecurrent plane,making conventional segmentation methods such as thresholding or the k-means algorithm *** study,we propose a multimodal machine learning approach that combines intensity information obtained at differentelectron beam accelerating voltages to improve the three-dimensional(3D)reconstruction of *** treatingthe increased shine-through effect at higher accelerating voltages as a form of additional information,the proposed methodsignificantly improves segmentation accuracy and leads to more precise 3D reconstructions for real FIB tomography data.

关键词： Multimodal machine learning Multi-voltage images FIB-SEM Overdeterministic systems 3D reconstruction FIB tomography

PRIMA NIDIFICAZIONE DI RONDINE ROSSICCIA Hirundo daurica IN PROVINCIA DI BRESCIA

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Natural Disaster Reduction in China 1993年第1期 299-300页

作者： GABRIELE PIOTTI MARKUS ritter via Roveglio 8 25087 SALO(Brescia) WaldenburgherStrasse 28 4052 BASEL(Svizzera)

Durante il mese di agosto 1993 si è osservata ripetutamente una coppia adulta,con quattro giovani già volanti,di Rondine rossiccia Hirundo daurica nel comunedi Gargnano (*** 35 Ⅲ SE,Gargnano).Le osservazioni si sono protratte dal 18 al 27 agosto,in un oliveto coltivato,esposto a SE e situato tra la via Prea e la strada statale 45 bis《Gardesana occidenta-le》,a circa 150 m s.l.m.I giovani erano già in grado di cacciare insetti in volo,ma ritornavano spesso al posatoio abituale costituito da un tratto di cavo telefonicoattraversante l’oliveto,dove venivano ancora imbeccati dai *** il

关键词： DI PRIMA NIDIFICAZIONE DI RONDINE ROSSICCIA Hirundo daurica IN PROVINCIA DI BRESCIA

Food supplementation by an invasive fleshy-fruited shrub sustains body condition of a native frugivorous bird during winter

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Integrative Zoology 2019年第3期14卷 259-269页

作者： tobias Nicolas ROJAS David Lautaro VERGARA-TABARES Diego Javier VALDEZ Marina Flavia PONZIO Susana Inés PELUC Institute of Diversity and Animal Eology(IDEA-CONICET) National University of CórdobaCórdobaArgentina Institute of Health Science Research(INICSA-CONICET) Faculty of Medical SciencesNational University of CórdobaCórdobaArgentina Faculty of Exacts Physics and Nature SciencesNational University of CórdobaCórdobaArgentina Instituto de Ecología Regional(IER-CONICET) National University of TucumánTucumánArgentina.

Birds tend to adjust their behavior and physiology to changes in food availability in their ***al fluctuation of food resources may act as an energetic challenge,augmenting hypothalamus-pituitary-adrenal axis(HPA axis)activity,leading to an increase in corticosterone concentrations and promoting the metabolism of energy *** invasions may alter seasonal food fluctuations by providing a food supply during scarce *** could attenuate the energetic challenge,reducing HPA axis activity and the metabolism of *** a system with seasonal fluctuation in food availability,we tested if fruit supplementation by the invasive fleshy-fruited Pyracantha angustifolia during the season of native fruit scarcity decreases the consumption of energy stores through activity attenuation of the HPA *** measured changes in body condition and circulating corticosterone(CORT)concentration in Turdus chiguanco occurring at sites both invaded and not invaded by *** over 3 time periods that correspond to the periods prior to,during and after highest fruit production of the *** scarcity in the ecosystem appears as an energetic challenge for ***co,given that body mass,fat score and residuals of body mass/tarsus length decreased during winter in a site not invaded by the exotic ***,the presence of the invasive plant seemed to attenuate the metabolism of energetic reserves,as we did not record changes in body condition in birds inhabiting the invaded ***,plasma CORT concentration did not vary between sites or *** evaluation is required to elucidate how enhanced body condition,resulting from the consumption of a fleshy-fruited invasive plant,affects survivorship and reproductive performance in ***.

关键词： biological invasion energetic reserves food fluctuation frugivory plasma corticosterone

Crohn's disease complicated by intestinal infection with methicillin-resistant Staphylococcus aureus

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World Journal of Gastroenterology 2013年第27期19卷 4418-4421页

作者： Dominik Bettenworth tobias M Nowacki Alexander Friedrich Karsten Becker Johannes Wessling Jan Heidemann Department of Medicine B University of Münster Institute of Hygiene University of Münster Institute of Medical Microbiology University of Münster Department of Clinical Radiology University of Münster

We report on a 24-year-old male patient with history of bloody diarrhea, abdominal pain and vomiting. Endoscopy revealed massive ulcerative discontinuous proctosigmoiditis with deep, sharply demarcated epithelial denudations and enterotoxigenic methicillin-resistant Staphylococcus aureus (MRSA) was detected in mucosal biopsies. After treatment with linezolide and steroids, a significant amelioration of colitis was detected and testing for MRSA became negative. In face of the case presented here, we suggest that in patients with refractory inflammatory bowel disease (IBD), microbiological assessment should be performed to detect a possible Staphylococcus aureus infection in order to initiate an antimicrobial treatment in addition to IBDspecific treatment.

关键词： Inflammatory bowel disease Crohn’s disease Infectious colitis Staphylococcus aureus Methicillin-resistant Staphylococcus aureus