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Promoting axon regeneration in the central nervous system by increasing PI3-kinase signaling

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Neural Regeneration Research 2022年第6期17卷 1172-1182页

作者： bart Nieuwenhuis Richard Eva John van Geest Center for Brain Repair Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK

Much research has focused on the PI3-kinase and PTEN signaling pathway with the aim to stimulate repair of the injured central nervous *** in the central nervous system fail to regenerate,meaning that injuries or diseases that cause loss of axonal connectivity have life-changing *** 2008,genetic de.etion of PTEN was ide.tified as a means of stimulating robust regeneration in the optic *** is a phosphatase that opposes the actions of PI3-kinase,a family of enzymes that function to generate the membrane phospholipid PIP_(3) from PIP_(2)(phosphatidylinositol(3,4,5)-trisphosphate from phosphatidylinositol(4,5)-bisphosphate).de.etion of PTEN therefore allows elevated signaling downstream of PI3-kinase,and was initially de.onstrated to promote axon regeneration by signaling through *** recently,additional mechanisms have been ide.tified that contribute to the neuron-intrinsic control of regenerative *** review de.cribes neuronal signaling pathways downstream of PI3-kinase and PIP3,and conside.s them in relation to both de.elopmental and regenerative axon *** briefly discuss the key neuron-intrinsic mechanisms that govern regenerative ability,and de.cribe how these are affected by signaling through *** highlight the recent finding of a de.elopmental de.line in the generation of PIP_(3) as a key reason for regenerative failure,and summarize the studies that target an increase in signaling downstream of PI3-kinase to facilitate regeneration in the adult central nervous ***,we discuss obstacles that remain to be overcome in orde. to generate a robust strategy for repairing the injured central nervous system through manipulation of PI3-kinase signaling.

关键词： axon cytoskeleton axon regeneration axon transport cell signaling central nervous system growth cone neuroprotection PI3-kinase PI3K PTEN trafficking transcription translation

Oral polymorphonuclear neutrophil characteristics in relation to oral health： a cross-sectional, observational clinical study

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International Journal of Oral Science 2016年第3期8卷 191-198页

作者： Patrick Rijkschroeff Ineke DC Jansen Fridus A van de. weijde. bart IF Keijser Bruno G loos Elena A Nicu de.artment of Periodontology Academic Centre for Dentistry Amsterdam Amsterdam The Netherlands de.artment of Preventive de.tistry Academic Centre for Dentistry Amsterdam Amsterdam The Netherlands Microbiology and Systems Biology TNO Earth Environmental and Life Sciences Zeist The Netherlands Top Institute Food and Nutrition Wageningen The Netherlands

Polymorphonuclear neutmphils （PMNs） have a major role in the innate immune system. However, little is known about PMN contribution in relation to oral health. The objective of this study was to investigate the numbers and functional characteristics of oral PMNs （oPMNs） compared with circulatory PMNs （cPMNs）. Oral rinse and venous blood samples were obtained from 268 systemically and orally healthy volunteers in a cross-sectional observational study. PMN counts, cell cycle analysis and cellular activation state were investigated. Also, reactive oxygen species （ROS） production was analyzed, with and without bacterial stimulation （Fusobacterium nucleatum）. In males, 1.2 × 10^6- 1.0 ×10^6 oPMNs were collected, and showed a tende.cy to correlate with the levels of gingival bleeding （r= 0.215, P= 0.008）. Comparable oPMNs counts were found among females （1.0 ×10^6＋ 0.7 × 10^6）. More late-stage apoptotic/necrotic cells were found among the oPMNs （53.1%） compared with the cPMNs （8.5%; P〈 0.001）. without additional stimulation, oPMNs were more activated than cPMNs, as indicated by higher expression of CD11b, CD63 and CD66b, and higher constitutive ROS levels （P〈 0.001）. Notably, in response to bacterial stimulation, oPMNs released comparable ROS levels as cPMNs （P= 0.042）. In conclusion, this study provide. data on viable oPMNs showing high levels of activation in orally and systemically healthy individuals, free of apparent caries lesions and periodontal disease. These data suggests that although the oPMNs are in a more mature stage of their life cycle compared with the cPMNs, oPMNs are still responsive to stimulation, which indicates their functional potential and possible contribution to a healthy oral ecosystem.

关键词： apoptosis de.ranulation neutrophils oral health reactive oxygen species

Reversed-phase fused-core HPlC mode.ing of peptide.

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Journal of Pharmaceutical Analysis 2013年第2期3卷 93-101页

作者： Matthias D'Hondt Bert Gevaert Sofie Stalmans Sylvia van Dorpe Evelien wynendaele Kathelijne Peremans Christian Burvenich bart de.Spiegeleer Drug Quality and Registration(DruQuaR) group Faculty of Pharmaceutical SciencesGhent UniversityHarelbekestraat 72B-9000 GhentBelgium de.artments of Medical Imaging and Physiology Faculty of Veterinary MedicineGhent UniversitySalisburylaan 133B9820 MerelbekeBelgium

Different fused-core stationary phase chemistries（C18,Amide.Phenyl-hexyl and Peptide.ES-C18） were used for the analysis of 21 structurally representative mode. *** addition,the effects of the mobile phase composition（ACN or MeOH as organic modifier;formic acid or acetic acid,as acidifying component） on the column selectivity,peak shape and overall chromatographic performance were *** RP-amide.column,combined with a formic acid-acetonitrile based gradient system,performed as best.A peptide.reversed-phase retention mode. is proposed,consisting of 5 variables：log SumAA,log Sv,clog P,log nHDon and log *** structure-retention relationship（QSRR） mode.s were constructed for 16 different chromatographic *** accuracy of this peptide.retention mode. was de.onstrated by the comparison between predicted and experimentally obtained retention times,explaining on average 86% of the ***,using an external set of 5 validation peptide.,the predictive power of the mode. was also *** peptide.retention mode. include. the novel in-silico calculated amino acid de.criptor,AA,which was calculated from log P,3D-MoRSE,RDF and wHIM de.criptors.

关键词： Peptide. Fused-core(core-shell core-enhanced poro-shell HAlO s) stationary phases RP-HPlC peptide.retention mode. In-silico amino acid de.criptor

Fixation methods for electron microscopy of human and other liver

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world Journal of Gastroenterology 2010年第23期16卷 2851-2866页

作者： Eddie wisse Filip Braet Hans Duimel Celien Vreuls Ger Koek Steven wM Olde.Damink Maartje AJ van de. Broek bart de.Geest Cees HC de.ong Chise Tateno Peter Frede.ik Electron Microscope Unit University of Maastricht Australian Key Center for Microscopy and Microanalysis Sydney University de.artment of Internal Medicine University of Maastricht de.artment of Surgery University of Maastricht Center for Molecular and Vascular Biology University of Leuven PhoenixBio Co.

For an electron microscopic study of the liver,expertise and complicated,time-consuming processing of hepatic tissues and cells is *** interpretation of electron microscopy(EM) images requires knowledge of the liver fine structure and experience with the numerous artifacts in fixation,embedding,sectioning,contrast staining and microscopic ***,the aim of this paper is to present a de.ailed summary of different methods for the preparation of hepatic cells and tissue,for the purpose of preserving long-standing expertise and to encourage new investigators and clinicians to include.EM studies of liver cells and tissue in their projects.

关键词： liver Tissue fixation Perfusion Electron microscopy Biopsy

Numerical analysis of the unsteady behavior of cloud cavitation around a hydrofoil based on an improved filter-based mode.

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Journal of Hydrodynamics 2015年第5期27卷 795-808页

作者：张德胜王海宇施卫东张光建 van ESCH B.P.M.(bart) Research Center of Fluid Machinery Engineering and Technology Jiangsu University de.artment of Mechanical Engineering Eindhoven University of Technology

The unsteady cavitation evolution around the Clark-Y hydrofoil is investigated in this paper, by using an improved filter-base mode.（FBM） with the de.sity correction method（DCM）. To improve the prediction accuracy, the filter scale is adjusted based on the grid size. The numerical results show that a small filter scale is crucial for the unsteady simulations of the cavity shedding flow. The hybrid method that combines the FBM and the DCM could help to limit the overprediction of the turbulent viscosity in the cavitation region on the wall of the hydrofoil and in the wake. The large value of the maximum de.sity ratio ρ1 /ρv, clip promotes the mass transfer rate between the liquid phase and the vapor phase, which results in a large sheet cavity length and the vapor fraction rise inside.the cavity. The cavity patterns predicted by the improved method are verified by the experimental visualizations. The time-average lift, the drag coefficient and the primary oscillating frequency St for the cavitation number σ= 0.8, the angle of attack, α= 8°, at a Reynolds number Re= 7×10^5 are 0.735, 0.115 and 0.183, respectively, and the predicted errors are 3.29%, 3.36% and 8.93%. The typical three stages in one revolution are well-captured, including the initiation of the sheet/attached cavity, the growth toward the trailing edge（TE） with the de.elopment of the re-entrant jet flow, and the large scale cloud cavity shedding. It is observed that the cloud cavity shedding flow induces the vortex pairs of the TE vortices in the wake and the shedding vortices. The positive vorticity vortex of the re-entrant jet and the TE vortices interacts and merges with the negative vorticity vortex of the leading edge（lE） cavity to produce the shedding flow.

关键词： filter-based mode.(FBM) de.sity correction method cloud cavitation hydrofoil unsteady behavior

Three-dimensional printing in paediatric orthopaedic surgery

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world Journal of Orthopedics 2022年第1期13卷 1-10页

作者： Sven Goetstouwers Dagmar Kempink Bertram The de.ise Eygendaal bart van Oirschot Christiaan JA van Bergen de.artment of Orthopaedic Surgery and Sports Medicine Erasmus Medical Centre/Sophia Children's HospitalRotterdam 3015GDSouth-HollandNetherlands de.artment of Orthopaedic Surgery Amphia HospitalBreda 4818CKNorth-BrabantNetherlands D lab Amphia HospitalBreda 4818CKNorth-BrabantNetherlands

Three-dimensional(3D)printing is a rapidly evolving and promising field to improve outcomes of orthopaedic *** use of patient-specific 3D-printed mode.s is specifically interesting in paediatric orthopaedic surgery,as limb de.ormity corrections often require an individual 3D *** this editorial,various operative applications of 3D printing in paediatric orthopaedic surgery are *** technical aspects and the imaging acquisition with computed tomography and magnetic resonance imaging are ***,there is a focus on the intraoperative applications of 3D printing during paediatric orthopaedic surgical *** overview of various upper and lower limb de.ormities in paediatrics is given,in which 3D printing is already implemented,including posttraumatic forearm corrections and proximal femoral *** use of patient-specific instrumentation(PSI)or guiding templates during the surgical procedure shows to be promising in reducing operation time,intraoperative haemorrhage and radiation ***,3D-printed mode.s for the use of PSI or patient-specific navigation templates are promising in improving the accuracy of complex limb de.ormity surgery in ***,the future of 3D printing in paediatric orthopaedics extends beyond the intraoperative applications;various other medical applications include.3D casting and prosthetic limb *** conclusion,3D printing opportunities are numerous,and the fast de.elopments are exciting,but more evide.ce is required to prove its superiority over conventional paediatric orthopaedic surgery.

关键词： Three-dimensional printing Paediatric Orthopaedic surgery Intraoperative Patient-specific instrumentation Guiding

CFD based extraction column de.ign-Chances and challenges

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Chinese Journal of Chemical Engineering 2016年第2期24卷 259-263页

作者： Mark w.Hlawitschka Menwer M.Attarakilh Samer S.Alzyod Hans-Jorg bart Chair of Separation Science and Technology POB 3049TU KaiserslauternKaiserslautern 67653Germany Center for Computational and Mathematical Mode.ling(CM2) TU KaiserslauternKaiserslautern 67653Germany University of Jordan Department of Chemical Engineering11942 AmmanJordan

This paper shows that one-dimensional （I-D） [and three-dimensional （3-D） computational fluid dynamics （CFD）] simulations can replace the state-of-the-art usage of pseudo-homogeneous dispersion or back mixing mode.s. This is based on standardized lab-scale cell experiments for the de.ermination of droplet rise, breakage, coalescence and mass transfer parameters in addition to a limited number of additional mini-plant experiments with original fluids. Alternatively, the hydrodynamic parameters can also be de.ived using more sophisticated 3- D CFD simulations. Computational 1-D mode.ing served as a basis to replace pilot-plant experiments in any column geometry. The combination of 3-D CFD simulations with droplet population balance mode.s （DPBM） increased the accuracy of the hydrodynamic simulations and gave information about the local droplet size. The high computational costs can be reduced by open source CFD code. when using a flexible mesh generation. First combined simulations using a three way coupled CFD/DPBM/mass-transfer solver pave the way for a safer de.ign of industrial-sized columns, where no correlations are available.

关键词： CFD DPBM Column de.ign

Humans ide.tify negative （but not positive） arousal in silver fox vocalizations： implications for the adaptive value of interspecific eavesdropping

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Current Zoology 2017年第4期63卷 445-456页

作者： Piera FIlIPPI Svetlana S. GOGOlEVA Elena V. VOlODINA Ilya A. VOlODIN bart de.BOER Artificial Intelligence laboratory Department of Computer Science Faculty of Science Vrije Universiteit Brussel Pleinlaan 2 1050 Brussels Belgium Brain and language Research Institute Aix-Marseille University Avenue Pasteur 5 13604 Aix-en-Provence France Max Planck Institute for Psycholinguistics Department of Language and Cognition Wundtlaan 1 6525 XD Nijmegen The Netherlands de.artment of Vertebrate Zoology Faculty of Biology Lomonosov Moscow State University Vorobievy Gory 1/12 119991 Moscow Russia Scientific Research de.artment Moscow Zoo B. Gruzinskaya 1 123242 Moscow Russia

The ability to ide.tify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans ide.tify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans＂ ability to ide.tify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can ide.tify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in ide.tifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans＇ ability to discriminate high-arousal calls across all strains. Furthermore, we ide.tified in spectral center of gravity and F0 the best predictors for humans＇ absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.

关键词： eavesdropping emotional arousal emotional valence inter-species communication silver foxes vocal communication.

Cerebral magnetic resonance imaging in quiescent Crohn's disease patients with fatigue

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world Journal of Gastroenterology 2017年第6期23卷 1018-1029页

作者： Sanne van Erp Ece Ercan Perla Breedveld lianne Brakenhoff Eidrees Ghariq Sophie Schmid Matthias van Osch Mark van Buchem bart Emmer Jeroen van de. Grond Ron wolterbeek Daniel Hommes Herma Fidde. Nic van de. wee Tom Huizinga Désirée van de. Heijde.Huub Midde.koop Itamar Ronen Andrea van de. Meulen-de.Jong de.artment of Gastroenterology and Hepatology Leiden University Medical Center C.J.Gorter Center Leiden University Medical Center de.artment of Radiology Leiden University Medical Center de.artment of Medical Statistics Leiden University Medical Center Center for Inflammatory Bowel Diseases University of California Los Angeles de.artment of Gastroenterology and Hepatology University Medical Center Utrecht de.artment of Psychiatry Leiden University Medical Center de.artment of Rheumatology Leiden University Medical Center de.artment of Neuropsychology Leiden University Medical Center de.artment of Radiology Leiden University Medical CenterLeiden

To evaluate brain involvement in quiescent Crohn’s disease (CD) patients with fatigue using quantitative magnetic resonance imaging (MRI).METHODSMultiple MRI techniques were used to assess cerebral changes in 20 quiescent CD patients with fatigue (de.ined with at least 6 points out of an 11-point numeric rating scale compared with 17 healthy age and gende. matched controls without fatigue. Furthermore, mental status was assessed by cognitive functioning, based on the neuropsychological inventory including the different domains global cognitive functioning, memory and executive functioning and in addition mood and quality of life scores. Cognitive functioning and mood status were correlated with MRI findings in the both study *** glutamate + glutamine (Glx = Glu + Gln) concentrations (P = 0.02) and ratios to total creatine (P = 0.02) were found in CD patients compared with controls. Significant increased Cerebral Blood Flow (P = 0.05) was found in CD patients (53.08 ± 6.14 ml/100 g/min) compared with controls (47.60 ± 8.62 ml/100 g/min). CD patients encountered significantly more de.ressive symptoms (P lated to memory (P = 0.007) and executive functioning (P = 0.02) were lower in CD patients and both scores showed correlation with de.ression and anxiety. No correlation was found subcortical volumes between CD patients and controls in the T1-weighted analysis. In addition, no correlation was found between mental status and MRI *** work shows evide.ce for perfusion, neurochemical and mental differences in the brain of CD patients with fatigue compared with healthy controls.

关键词： Magnetic resonance imaging Systemic inflammation Fatigue Crohn’s disease Cognition