Scientific publications

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We read, with great interest, the article entitled “Computerized measurement of the location and value of the minimum sagittal linear dimension of the upper airway on reconstructed lateral cephalograms compared with 3-dimensional values” (Alwadei AH, Galang-Boquiren MTS, Kusnoto B, et al. Am J Orthod Dentofacial Orthop 2018;154:780-787). Alwadei et al used cone-beam computed tomography (CBCT) and described significant correlations between the minimum sagittal linear dimension on reconstructed lateral cephalograms and both the minimum cross-sectional area and the airway volume. This article was a valuable contribution to the evolving debate on the diagnostic tools for obstructive sleep apnea (OSA).


Heterogeneous mixture of amniotic cells is likely a better source of stem cells than adipose tissue


Diana Kitala, Agnieszka Klama-Baryła, Marcelina Misiuga, Wojciech Łabuś, Małgorzata Kraut, Michał Szapski, Marta Lesiak, Daniel Krakowian, Aleksander Sieroń, Marek Łos, Marek Kucharzewski

DOI 10.1007/s00005-019-00538-5
Scientific Field Life & Health Sciences
Fellow Prof. Marek Los
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Stem cells are increasingly being used in the course of burn treatment. As several different types of stem cells are available for the purposes, it is important to chose the most efficient and the most practicable stem cell type. The aim of this study was to compare the potential of heterogeneous amnion cell mixture with the presently used standard therapy, the adipose tissue-derived stem cells. The placenta was collected during a Cesarean section procedure. Adipose tissue tissue-derived cells were isolated using the Cytori’s Celution® System. Cells were tested for fulfillment of the minimum criteria for stem cells. The efficiency of cell cultures was tested by an analysis of population doubling, cell proliferation, cell cycle and cell migration. Amniotic cells presented a higher ability for differentiation to chondrocytes and osteocytes than adipose-derived regenerative cells but a lower ability for differentiation toward adipocytes. Additionally, in vitro experiments have demonstrated a higher applicability of amniotic cells than adipose tissue-derived stem cells. Amniotic cells show several advantages: easy access to placenta, low costs and a lack of ethical dilemmas related to stem cell harvesting. The main disadvantage is, however, their availability, as isogenic treatment would only be possible for women around children-bearing age, unless personalized banks for amniotic cells would be established.


Surface PEG Grafting Density Determines Magnetic Relaxation Properties of Gd-Loaded Porous Nanoparticles for MR Imaging Applications


Wuyuan Zhang, Jonathan Martinelli, Joop A. Peters, Jacob M.A. van Hengst, Hans Bouwmeester, Evelien Kramer, Celia S. Bonnet, Frederic Szeremeta, Éva Tóth, Kristina Djanashvili

DOI 10.1021/acsami.7b05912
Scientific Field Life & Health Sciences
Fellow Dr Kristina Djanashvili
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Surface PEGylation of nanoparticles designed for biomedical applications is a common and straightforward way to stabilize the materials for in vivo administration and to increase their circulation time. This strategy becomes less trivial when MRI active porous nanomaterials are concerned as their function relies on water/proton-exchange between the pores and bulk water. Here we present a comprehensive study on the effects of PEGylation on the relaxometric properties of nanozeolite LTL (dimensions of 20 × 40 nm) ion-exchanged with paramagnetic GdIII ions. We evidence that as long as the surface grafting density of the PEG chains does not exceed the “mushroom” regime (conjugation of up to 6.2 wt % of PEG), Gd-LTL retains a remarkable longitudinal relaxivity (38 s–1 mM–1 at 7 T and 25 °C) as well as the pH-dependence of the longitudinal and transverse relaxation times. At higher PEG content, the more compact PEG layer (brush regime) limits proton/water diffusion and exchange between the interior of LTL and the bulk, with detrimental consequences on relaxivity. Furthermore, PEGylation of Gd-LTL dramatically decreases the leakage of toxic GdIII ions in biological media and in the presence of competing anions, which together with minimal cytotoxicity renders these materials promising probes for MRI applications.


Cellular and Subcellular Compartmentation of the 2C-Methyl-D-Erythritol 4-Phosphate Pathway in the Madagascar Periwinkle


Grégory Guirimand, Anthony Guihur, Catalina Perello, Michael Phillips, Samira Mahroug, Audrey Oudin, Thomas Duge de Bernonville, Sébastien Besseau, Arnaud Lanoue, Nathalie Giglioli-Guivarc’h, Nicolas Papon, Benoit St-Pierre, Manuel Rodríguez-Concepción, Vincent Burlat, Vincent Courdavault

DOI https://doi.org/10.3390/plants9040462
Scientific Field Life & Health Sciences
Fellow Dr Grégory Guirimand
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The Madagascar periwinkle (Catharanthus roseus) synthesizes the highly valuable monoterpene indole alkaloids (MIAs) through a long metabolic route initiated by the 2C-methyl-D-erythritol 4-phosphate (MEP) pathway. In leaves, a complex compartmentation of the MIA biosynthetic pathway occurs at both the cellular and subcellular levels, notably for some gene products of the MEP pathway. To get a complete overview of the pathway organization, we cloned four genes encoding missing enzymes involved in the MEP pathway before conducting a systematic analysis of transcript distribution and protein subcellular localization. RNA in situ hybridization revealed that all MEP pathway genes were coordinately and mainly expressed in internal phloem-associated parenchyma of young leaves, reinforcing the role of this tissue in MIA biosynthesis. At the subcellular level, transient cell transformation and expression of fluorescent protein fusions showed that all MEP pathway enzymes were targeted to plastids. Surprisingly, two isoforms of 1-deoxy-D-xylulose 5-phosphate synthase and 1-deoxy-D-xylulose 5-phosphate reductoisomerase initially exhibited an artifactual aggregated pattern of localization due to high protein accumulation. Immunogold combined with transmission electron microscopy, transient transformations performed with a low amount of transforming DNA and fusion/deletion experiments established that both enzymes were rather diffuse in stroma and stromules of plastids as also observed for the last six enzymes of the pathway. Taken together, these results provide new insights into a potential role of stromules in enhancing MIA precursor exchange with other cell compartments to favor metabolic fluxes towards the MIA biosynthesis.


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This article analyses the relationship of Pietro Bembo's Prose with the introductory Epistola of the Raccolta Aragonese and Cristoforo Landino's proemio to his Comento sopra la Comedia, with regard to their views of the previous vernacular tradition and in particular the more or less comparable paradigms applied to past literary history. The question of whether Bembo knew Poliziano's Epistola is investigated, and the similarities and dissimilarities between the different narratives concerning cultural development and the ways in which these narratives are elaborated in the three texts are evaluated.


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Lorsque l’on évoque le phénomène de la contrefaçon sous l’Ancien Régime, les historiens du livre se montrent parfois hésitants sur l’acceptation qu’il convient de lui donner : faut-il le limiter à l’aspect strictement juridique ou doit-on plutôt l’étendre au domaine éthique ? Ils s’entendent toutefois sur le préjudice porté à l’auteur, au créateur ou encore au producteur victime de la contrefaçon. De notre point de vue, et même s’il n’est pas toujours aisé de saisir pleinement les contours de cette notion, nous réconcilierions volontiers les deux acceptations en employant les formules suivantes : la « contrefaçon stricto sensu » qui renvoie à l’aspect purement juridique et la « contrefaçon lato sensu » qui élargit le concept à l’imitation frauduleuse d’un ouvrage (page de titre, adresse bibliographique, mise en page…).


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This paper presents an analysis of the effect of the droplet support fiber on the droplet evaporation process. This effect is evaluated for a droplet evaporating in a hot environment at atmospheric pressure using the experimental results of the present study and those in the literature. Selected published results are acquired using similar test conditions and experimental setups as the present data. The only main difference between these studies is the droplet support fiber diameter which varies between 14 µm and 225 µm. The ambient temperature explored in these studies ranges from room temperature up to 973 K. n-Heptane is selected because it is the most common fuel used in these studies. The main findings are that the cross-fiber technique, which uses 14 µm fiber diameters, induces no noticeable heat transfer into the droplet and consequently does not interfere with the evaporation process. In contrast, the classical fiber technique, which uses relatively larger fibers, greatly enhances the droplet evaporation rate as a consequence of increased conduction heat transfer through the fiber. A correlation is proposed to quantify the level of this increase as a function of ambient temperature and the fiber cross-sectional area.


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The study of the Weyl and Dirac topological materials (topological semimetals, insulators, superfluids and superconductors) opens the route for the investigation of the topological quantum vacua of relativistic fields. The symmetric phase of the standard model (SM), where both electroweak and chiral symmetry are not broken, represents the topological semimetal. The vacua of the SM (and its extensions) in the phases with broken electroweak symmetry represent the topological insulators of different types. We discuss in detail the topological invariants in both the symmetric and broken phases and establish their relation to the stability of vacuum.


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In this paper, firstly, a new method which makes a modification of the Bern-stein polynomials is introduced to solve the linear fractional partial differential equations (FPDEs). The biggest advantage of the fractional Bernstein polynomials is that the order can be changed with the order of the fractional partial differential equations. For the first time, we try to use this method to solve the linear fractional partial differential equations. Secondly, convergence analysis and error correction are also given to make the calculation results more accurate. The concrete content of this method and error correction are explained briefly and numerical examples are given to demonstrate the validity and accuracy of the method.


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In this paper, an effective numerical algorithm is proposed for the first time to solve the fractional visco-elastic rotating beam in the time domain. On the basis of fractional derivative Kelvin–Voigt and fractional derivative element constitutive models, the two governing equations of fractional visco-elastic rotating beams are established. According to the approximation technique of shifted Chebyshev polynomials, the integer and fractional differential operator matrices of polynomials are derived. By means of the collocation method and matrix technique, the operator matrices of governing equations can be transformed into the algebraic equations. In addition, the convergence analysis is performed. In particular, unlike the existing results, we can get the displacement and the stress numerical solution of the governing equation directly in the time domain. Finally, the sensitivity of the algorithm is verified by numerical examples.