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排序方式: 共有551条查询结果,搜索用时 0 毫秒
21.
Claudia Siverino Shorouk Fahmy-Garcia Didem Mumcuoglu Heike Oberwinkler Markus Muehlemann Thomas Mueller Eric Farrell Gerjo J. V. M. van Osch Joachim Nickel 《International journal of molecular sciences》2022,23(7)
For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2′s bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs. 相似文献
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Hanna Mannell Petra Kameritsch Heike Beck Alexander Pfeifer Ulrich Pohl Kristin Pogoda 《International journal of molecular sciences》2022,23(1)
The gap junction protein connexin 43 (Cx43) is associated with increased cell migration and to related changes of the actin cytoskeleton, which is mediated via its C-terminal cytoplasmic tail and is independent of its channel function. Cx43 has been shown to possess an angiogenic potential, however, the role of Cx43 in endothelial cell migration has not yet been investigated. Here, we found that the knock-down of Cx43 by siRNA in human microvascular endothelial cells (HMEC) reduces migration, as assessed by a wound assay in vitro and impaired aortic vessel sprouting ex vivo. Immunoprecipitation of Cx43 revealed an interaction with the tyrosine phosphatase SHP-2, which enhanced its phosphatase activity, as observed in Cx43 expressing HeLa cells compared to cells treated with an empty vector. Interestingly, the expression of a dominant negative substrate trapping mutant SHP-2 (CS) in HMEC, via lentiviral transduction, also impaired endothelial migration to a similar extent as Cx43 siRNA compared to SHP-2 WT. Moreover, the reduction in endothelial migration upon Cx43 siRNA could not be rescued by the introduction of a constitutively active SHP-2 construct (EA). Our data demonstrate that Cx43 and SHP-2 mediate endothelial cell migration, revealing a novel interaction between Cx43 and SHP-2, which is essential for this process. 相似文献
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The M?bius strip trade fair stand was designed and built by students of the Faculty of Architecture of Darmstadt Technical
University in collaboration with students of the Faculty of Mathematics. The project focused on two main issues: to introduce
computer-driven parametric design and production strategies, techniques and technologies into architectural education, and
to build and operate the final result. This required knowledge of different software packages and readiness to become familiar
quickly with unknown data formats, flexibility in the time schedule and disposition to transport the material to the machinery.
It introduced students to the possibilities of designing with parametric modeling software and familiarized them with the
initial difficulties and ample payback in actual production. 相似文献
26.
S. V. Nikolenko 《Russian Engineering Research》2011,31(6):556-561
The formation of an alloyed layer on steel 35 by VK8 hard alloy with added Al2O3 increases its wear resistance. Effective conditions for this process are determined. The formation of regular tungsten-carbide
nanostructure is observed. 相似文献
27.
Marcel Müri Bernd Gotsmann Yann Leroux Marius Trouwborst Emanuel Lörtscher Heike Riel Marcel Mayor 《Advanced functional materials》2011,21(19):3706-3714
Due to the increasing importance of modified electrodes for many applications in nanotechnology, including molecular electronics, bioelectronics, and sensors, there is a need to find ways to chemically attach suitable molecular films onto the electrodes. Combining the electroreduction of aryl diazonium salts with the Sonogashira cross‐coupling reaction, a new modular technique to modify electrodes is presented. The new technique allows a wide range of functional groups to be introduced onto electrode surfaces with high surface coverage by the functional subunit. Various organic subunits, including redox chromophores, are successfully attached to platinum electrodes. The corresponding films are characterized using cyclic voltammetry, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. The electroreduction of diazonium salts is successfully achieved on a broad variety of conducting and semiconducting surfaces, which shows that the technique is applicable to a broad variety of substrates. 相似文献
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V. V. Zabrodskiy P. N. Aruev V. P. Belik B. Ya. Ber D. Yu. Kazantsev M. V. Drozdova N. V. Zabrodskaya M. S. Lazeeva A. D. Nikolenko V. L. Sukhanov V. V. Filimonov E. V. Sherstnev 《Semiconductors》2013,47(2):213-216
The spatial homogeneity of the photoresponse is studied for silicon photodiodes based on p-n and n-p junctions a year after their irradiation at a wavelength of 121.6 nm and those based on n-p junctions four years after their irradiation with soft X-rays. It is demonstrated that silicon photodiodes based on p-n junctions exhibit a photoresponse recovery effect on being irradiated at a wavelength of 121.6 nm. No recovery effect is observed for silicon photodiodes based on n-p structures. 相似文献
30.