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91.
Monika Bednarczyk Carolina Medina-Montano Frederic Julien Fittler Henner Stege Meike Roskamp Michael Kuske Christian Langer Marco Vahldieck Evelyn Montermann Ingrid Tubbe Nadine Rhrig Andrzej Dzionek Stephan Grabbe Matthias Bros 《International journal of molecular sciences》2021,22(6)
The development of nanocarriers (NC) for biomedical applications has gained large interest due to their potential to co-deliver drugs in a cell-type-targeting manner. However, depending on their surface characteristics, NC accumulate serum factors, termed protein corona, which may affect their cellular binding. We have previously shown that NC coated with carbohydrates to enable biocompatibility triggered the lectin-dependent complement pathway, resulting in enhanced binding to B cells via complement receptor (CR)1/2. Here we show that such NC also engaged all types of splenic leukocytes known to express CR3 at a high rate when NC were pre-incubated with native mouse serum resulting in complement opsonization. By focusing on dendritic cells (DC) as an important antigen-presenting cell type, we show that CR3 was essential for binding/uptake of complement-opsonized NC, whereas CR4, which in mouse is specifically expressed by DC, played no role. Further, a minor B cell subpopulation (B-1), which is important for first-line pathogen responses, and co-expressed CR1/2 and CR3, in general, engaged NC to a much higher extent than normal B cells. Here, we identified CR-1/2 as necessary for binding of complement-opsonized NC, whereas CR3 was dispensable. Interestingly, the binding of complement-opsonized NC to both DC and B-1 cells affected the expression of activation markers. Our findings may have important implications for the design of nano-vaccines against infectious diseases, which codeliver pathogen-specific protein antigen and adjuvant, aimed to induce a broad adaptive cellular and humoral immune response by inducing cytotoxic T lymphocytes that kill infected cells and pathogen-neutralizing antibodies, respectively. Decoration of nano-vaccines either with carbohydrates to trigger complement activation in vivo or with active complement may result in concomitant targeting of DC and B cells and thereby may strongly enhance the extent of dual cellular/humoral immune responses. 相似文献
92.
Valentine N'da Kouam Stephan Handschin Matthias Derungs Georges N'guessan Amani Batrice Conde‐Petit 《Starch - St?rke》2011,63(12):747-753
Starches isolated from yam varieties of Dioscorea alata and Dioscorea cayenensis‐rotundata species were prepared at different time–temperature conditions and characterised by DSC, amperometric iodine titration, light microscopy and rheology and compared to native and chemical modified tapioca starches. The observation by light microscopy showed different morphologies of the granules when heated above 100°C and the tendency for disintegration decreased in the order native tapioca starch > yam starch > modified tapioca starch. Differences between yam and tapioca starches were also revealed by DSC. Yam starch enthalpy is higher than tapioca starch, but the peak temperature is low. However, the significant differences between yam and the other tested starches were found in terms of their rheological behaviour. The viscosity of yam starch was very stable at high temperatures on the viscograph. With this property, yam starch can be used as thickening and gelling agent in food. 相似文献
93.
Abstract. In this article, we study and compare the properties of several bootstrap unit‐root tests recently proposed in the literature. The tests are Dickey–Fuller (DF) or Augmented DF, based either on residuals from an autoregression and the use of the block bootstrap or on first‐differenced data and the use of the stationary bootstrap or sieve bootstrap. We extend the analysis by interchanging the data transformations (differences vs. residuals), the types of bootstrap and the presence or absence of a correction for autocorrelation in the tests. We show that two sieve bootstrap tests based on residuals remain asymptotically valid. In contrast to the literature which focuses on a comparison of the bootstrap tests with an asymptotic test, we compare the bootstrap tests among themselves using response surfaces for their size and power in a simulation study. This study leads to the following conclusions: (i) augmented DF tests are always preferred to standard DF tests; (ii) the sieve bootstrap performs better than the block bootstrap; (iii) difference‐based tests appear to have slightly better size properties, but residual‐based tests appear more powerful. 相似文献
94.
Sandra Lange Dr. Stephan M. Hacker Philipp Schmid Prof. Dr. Martin Scheffner Prof. Dr. Andreas Marx 《Chembiochem : a European journal of chemical biology》2017,18(17):1707-1711
The tumor suppressor Fhit and its substrate diadenosine triphosphate (Ap3A) are important factors in cancer development and progression. Fhit has Ap3A hydrolase activity and cleaves Ap3A into adenosine monophosphate (AMP) and adenosine diphosphate (ADP); this is believed to terminate Fhit‐mediated signaling. How the catalytic activity of Fhit is regulated and how the Fhit ? Ap3A complex might exert its growth‐suppressive function remain to be discovered. Small‐molecule inhibitors of the enzymatic activity of Fhit would provide valuable tools for the elucidation of its tumor‐suppressive functions. Here we describe the development of a high‐throughput screen for the identification of such small‐molecule inhibitors of Fhit. Two clusters of inhibitors that decreased the activity of Fhit by at least 90 % were identified. Several derivatives were synthesized and exhibited in vitro IC50 values in the nanomolar range. 相似文献
95.
Jadran Vrabec Martin Bernreuther Hans‐Joachim Bungartz Wei‐Lin Chen Wilfried Cordes Robin Fingerhut Colin W. Glass Jürgen Gmehling René Hamburger Manfred Heilig Matthias Heinen Martin T. Horsch Chieh‐Ming Hsieh Marco Hülsmann Philip Jäger Peter Klein Sandra Knauer Thorsten Köddermann Andreas Köster Kai Langenbach Shiang‐Tai Lin Philipp Neumann Jürgen Rarey Dirk Reith Gábor Rutkai Michael Schappals Martin Schenk Andre Schedemann Mandes Schönherr Steffen Seckler Simon Stephan Katrin Stöbener Nikola Tchipev Amer Wafai Stephan Werth Hans Hasse 《化学,工程师,技术》2018,90(3):295-306
This article outlines advances in molecular modeling and simulation using massively parallel high‐performance computers (HPC). In the SkaSim project, partners from the HPC community collaborated with users from science and industry. The aim was to optimize the prediction of thermodynamic property data in terms of efficiency, quality and reliability using HPC methods. In this context, various topics were dealt with: atomistic simulation of homogeneous gas bubble formation, surface tension of classical fluids and ionic liquids, multicriteria optimization of molecular models, the development of the molecular simulation codes ls1 mardyn and ms2, atomistic simulation of gas separation processes, molecular membrane structure generators, transport resistors and the evaluation of predictive property data models based on specific mixture types. 相似文献
96.
97.
Damien Serret Stephan Guignard Lounès Tadrist 《Microgravity science and technology》2009,21(1-2):101-105
Heat transfer prediction under boiling condition is still unresolved. In this paper, a basic study on bubble growth is carried out. Recent works show that contact line region plays an important role for heat and mass transfer in nucleate boiling regime. Three dimension experimental set-up lead to a mirage effect which disturbs measurements. To overcome this problem, a new quasi two dimensional experimental set-up is designed. This Hele–Shaw like configuration allows measuring the contact angle and contact line displacement during the bubble growth. A noticeable behavior of the contact angle is observed, and the influence of the sub-cooling level on the bubble growth rate and the contact angle value is studied. 相似文献
98.
介绍针对改善医院,学校及公共建筑等不同的建筑类型的研究,讨论行动研究、基础研究、应用研究这三种研究者与组织机构之间合作的例子,以促进负责任的环境实践. 相似文献
99.
100.
Yvonne Serfert Stephan Drusch Benjamin Schmidt-Hansberg Matthias Kind Karin Schwarz 《Journal of food engineering》2009,95(3):386-392
Aim of the present study was to investigate the impact of the emulsifying carrier matrix constituent, n-octenylsuccinate-derivatised (OSA)-starch, and process conditions on physical characteristics and oxidative stability of microencapsulated fish oil. Furthermore, the effect of the drying medium, i.e. air or nitrogen, on lipid oxidation during spray-drying and subsequent storage was investigated. Particle characteristics and lipid oxidation of microencapsulated fish oil were both influenced by the type of OSA-starch and the drying conditions. The highest oxidative stability was observed for fish oil microencapsulated in OSA-starch with the lowest average molecular weight and glucose syrup spray-dried at a moderate temperature setting. Particle characteristics of the microcapsules were not attributable for differences in lipid oxidation during storage. In spray-dried carrier matrix particles, the particle size increased with increasing average molecular weight of the OSA-starch and was attributed to an increase in air inclusion. Thus differences in lipid oxidation of the microencapsulated fish oil were attributed to differences in air inclusion as affected by the type of OSA-starch. In terms of spray-drying under inert conditions and in the presence of air, lipid oxidation of microencapsulated fish oil was rather attributed to oxygen availability in the feed emulsion than in the drying gas. 相似文献