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1.
Rafaelle Spear Ludovic Boytard Renaud Blervaque Maggy Chwastyniak David Hot Jonathan Vanhoutte Bart Staels Yves Lemoine Nicolas Lamblin Fran?ois-René Pruvot Stephan Haulon Philippe Amouyel Florence Pinet 《International journal of molecular sciences》2015,16(5):11276-11293
Abdominal aortic aneurysm (AAA) is an inflammatory disease associated with marked changes in the cellular composition of the aortic wall. This study aims to identify microRNA (miRNA) expression in aneurysmal inflammatory cells isolated by laser microdissection from human tissue samples. The distribution of inflammatory cells (neutrophils, B and T lymphocytes, mast cells) was evaluated in human AAA biopsies. We observed in half of the samples that adventitial tertiary lymphoid organs (ATLOs) with a thickness from 0.5 to 2 mm were located exclusively in the adventitia. Out of the 850 miRNA that were screened by microarray in isolated ATLOs (n = 2), 164 miRNAs were detected in ATLOs. The three miRNAs (miR-15a-3p, miR-30a-5p and miR-489-3p) with the highest expression levels were chosen and their expression quantified by RT-PCR in isolated ATLOs (n = 4), M1 (n = 2) and M2 macrophages (n = 2) and entire aneurysmal biopsies (n = 3). Except for the miR-30a-5p, a similar modulation was found in ATLOs and the two subtypes of macrophages. The modulated miRNAs were then evaluated in the plasma of AAA patients for their potential as AAA biomarkers. Our data emphasize the potential of miR-15a-3p and miR-30a-5p as biomarkers of AAA but also as triggers of ATLO evolution. Further investigations will be required to evaluate their targets in order to better understand AAA pathophysiology. 相似文献
2.
Sebastian Roth Peter Stockinger Jakob Steff Simon Steimle Dr. Viktor Sautner Prof. Dr. Kai Tittmann Prof. Dr. Jürgen Pleiss Prof. Dr. Michael Müller 《Chembiochem : a European journal of chemical biology》2020,21(18):2615-2619
The family of NAD(P)H-dependent short-chain dehydrogenases/reductases (SDRs) comprises numerous biocatalysts capable of C=O or C=C reduction. The highly homologous noroxomaritidine reductase (NR) from Narcissus sp. aff. pseudonarcissus and Zt_SDR from Zephyranthes treatiae, however, are SDRs with an extended imine substrate scope. Comparison with a similar SDR from Asparagus officinalis (Ao_SDR) exhibiting keto-reducing activity, yet negligible imine-reducing capability, and mining the Short-Chain Dehydrogenase/Reductase Engineering Database indicated that NR and Zt_SDR possess a unique active-site composition among SDRs. Adapting the active site of Ao_SDR accordingly improved its imine-reducing capability. By applying the same strategy, an unrelated SDR from Methylobacterium sp. 77 (M77_SDR) with distinct keto-reducing activity was engineered into a promiscuous enzyme with imine-reducing activity, thereby confirming that the ability to reduce imines can be rationally introduced into members of the “classical” SDR enzyme family. Thus, members of the SDR family could be a promising starting point for protein approaches to generate new imine-reducing enzymes. 相似文献
3.
4.
Christian Stephan Bernd 《AEUE-International Journal of Electronics and Communications》2006,60(1):20-24
Security for ad hoc network environments has received a lot of attention as of today. Previous work has mainly been focussing on secure routing, fairness issues, and malicious node detection. However, the issue of introducing and conserving trust relationships has received considerably less attention. In this article, we present a scalable method for the use of public key certificates and their revocation in mobile ad hoc networks (MANETs). With the LKN-ad hoc security framework (LKN-ASF) a certificate management protocol has been introduced, bringing PKI technology to MANETs. In addition a performance analysis of two different revocation approaches for MANETs will be presented. 相似文献
5.
Using an integrated process of data and modeling in HRA 总被引:1,自引:0,他引:1
John Wreathall Dennis Bley Emilie Roth Jordan Multer Thomas Raslear 《Reliability Engineering & System Safety》2004,83(2):221
The paper describes an approach taken to estimate the probabilities of failure associated with various railroad tasks to prevent accidents (principally collisions and derailments). These probabilities were estimated using an expert elicitation process that used partially relevant data available from a variety of databases and that were filtered and scaled to make them more directly relevant to the analyses being performed. Extensive qualitative studies were performed prior to the elicitation process to identify relevant contexts under which the tasks can be performed. 相似文献
6.
The Determinants of Debt and (Private) Equity Financing: The Case of Young, Innovative SMEs from Germany 总被引:1,自引:0,他引:1
Financial theory creates a puzzle. Some authors argue that high-risk entrepreneurs choose debt contracts instead of equity contracts since risky but high returns are of relatively more value for a loan-financed firm. Conversely, authors who focus explicitly on start-up finance predict that entrepreneurs are the more likely to seek equity-like venture capital contracts, the more risky their projects are. Our paper is an initial step towards resolving this puzzle empirically. We present microeconometric evidence on the determinants of debt and equity financing in young and innovative SMEs. We pay special attention to the role of risk for the choice of the method of financing. Since risk is not directly observable we use different indicators for financial and project risk. It turns out that our data generally confirms the hypothesis that the probability that a young high-tech firm receives equity financing is an increasing function of the financial risk. With regard to the intrinsic project risk, our results are less conclusive, as some of our indicators of a risky project are found to have a negative effect on the likelihood to be financed by private equity. 相似文献
7.
J.M. Roth T.G. Ulmer N.W. Spellmeyer S. Constantine M.E. Grein 《Photonics Technology Letters, IEEE》2004,16(9):2009-2011
We demonstrate a novel 40-GHz mode-locked fiber laser that utilizes a single active device to provide both gain and mode-locking. The laser produces pulses as short as 2.2 ps, is tunable over a 27-nm band centered at 1553 nm, and exhibits long-term stability without cavity-length feedback control. The pulse train at 1556 nm was used in a 40-Gb/s transmission experiment over 45 km with a low 0.4-dB power penalty. 相似文献
8.
Approximately 80% of the international transport of goods is carried on by means of ships. A large portion of the transport
capacity is represented by Roll-on-Roll-off (RoRo) ships. Especially in Europe this is a relevant potential for the RoRo segment.
Consequently, the design and construction of RoRo ships plays an increasing role for German shipyards and their suppliers.
In order to make the loading and unloading procedure of trailer economically more competitive, ship owners would like to improve
the lashing of trailers on the ship. On the basis of a multibody system formalism, a software tool has been developed which
allows for an optimization of the loading of trailers on RoRo ships.
Commemorative Contribution. 相似文献
9.
Eich (1985) recently presented a distributed memory model in which the pattern of results used to support the levels-of-processing view of Craik and Lockhart (1972) was modeled by different degrees of similarity between the encoding context and the to-be-recalled item. We report two experiments in which both phonemic and semantic similarity were varied between pairs of words and incidental acquisition (rhyme vs. category judgments) was varied across the same pairs of items. In both experiments the manipulation of the acquisition task produced a difference in cued-recall performance for positive and negative rhyme and category judgments. Recall was better following a category encoding decision than following a rhyme decision. This difference was independent of the effects of similarity, which demonstrated that Eich's (1985) assumptions regarding the effects of similarity are not sufficient to account for the differences resulting from the manner in which subjects encode information. An alternative method of modeling the levels-of-processing effect within the framework of distributed memory models is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
According to the knowledge partitioning framework, people sometimes master complex tasks by creating multiple independent parcels of partial knowledge. Research has shown that knowledge parcels may contain mutually contradictory information, and that each parcel may be used without regard to knowledge that is demonstrably present in other parcels. This article reports 4 experiments that investigated knowledge partitioning in categorization. When component boundaries of a complex categorization were identified by a context cue, a significant proportion of participants learned partial and independent categorization strategies that were chosen on the basis of context. For those participants, a strategy used in one context was unaffected by knowledge demonstrably present in other contexts, suggesting that knowledge partitioning in categorization can be complete. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献