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61.
Teng M Johnson MD Thomas C Kiel D Lakis JN Kercher T Aytes S Kostrowicki J Bhumralkar D Truesdale L May J Sidelman U Kodra JT Jørgensen AS Olesen PH de Jong JC Madsen P Behrens C Pettersson I Knudsen LB Holst JJ Lau J 《Bioorganic & medicinal chemistry letters》2007,17(19):5472-5478
Following our previous publication describing the biological profiles, we herein describe the structure-activity relationships of a core set of quinoxalines as the hGLP-1 receptor agonists. The most potent and efficacious compounds are 6,7-dichloroquinoxalines bearing an alkyl sulfonyl group at the C-2 position and a secondary alkyl amino group at the C-3 position. These findings serve as a valuable starting point for the discovery of more drug-like small molecule agonists for the hGLP-1 receptor. 相似文献
62.
Schmiedl A Behrens J Zscheppang K Purevdorj E von Mayersbach D Liese A Dammann CE 《American journal of physiology. Lung cellular and molecular physiology》2011,301(4):L490-L499
Pulmonary ErbB4 deletion leads to a delay in fetal lung development, alveolar simplification, and lung function disturbances in adult mice. We generated a model of intrauterine infection in ErbB4 transgenic mice to study the additive effects of antenatal LPS administration and ErbB4 deletion during fetal lung development. Pregnant mice were treated intra-amniotically with an LPS dose of 4 μg at E17 of gestation. Lungs were analyzed 24 h later. A significant influx of inflammatory cells was seen in all LPS-treated lungs. In heterozygote control lungs, LPS treatment resulted in a delay of lung morphogenesis characterized by a significant increase in the fraction of mesenchyme, a decrease in gas exchange area, and disorganization of elastic fibers. Surfactant protein (Sftp)b and Sftpc were upregulated, but mRNA of Sftpb and Sftpc was downregulated compared with non-LPS-treated controls. The mRNA of Sftpa1 and Sftpd was upregulated. In ErbB4-deleted lungs, the LPS effects were more pronounced, resulting in a further delay in morphological development, a more pronounced inflammation in the parenchyma, and a significant higher increase in all Sftp. The effect on Sftpb and Sftpc mRNA was somewhat different, resulting in a significant increase. These results imply a major role of ErbB4 in LPS-induced signaling in structural and functional lung development. 相似文献
63.
Background
The aqueous humor (AH), a liquid of the anterior and posterior chamber of the eye, comprises many proteins with various roles and important biological functions. Many of these proteins have not been identified yet and their functions in AH are still unknown. Recently, our laboratory published the protein database of AH obtained from healthy rabbits which expanded known protein identifications by 65%. Our present study extends our previous work and analyses AH following two types of cataract surgery incision procedures (clear corneal and limbal incisions) by using two dimensional gel electrophoresis (2-DE) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Although both incision protocols are commonly used during cataract surgeries, the difference in protein composition and their release into AH following each surgery has never been systematically compared and remains unclear. The first step, which is the focus of this work, is to assess the scale of the protein change, at which time does maximum release occurs and when possible, to identify protein changes. 相似文献64.
65.
Long runs of seasonal rotifer population data allow analysis of seasonal occurrence using mathematical tools. The application of Fourier analysis to a 15 year dataset describes seasonality in simple mathematical terms. This facilitates comparison of population expression with potential population driving variables and provides a basic modelling tool. Results show that annual patterns of occurrence and density have linkages with annual maximum and minimum environmental temperature, although the exact relationships are not clear. 相似文献
66.
Reaction of [MoO2(acac)2] with (S is a thioether, S′ a thiophenolate function) yielded the compound Li7(thf)17{MoO}8 · 10thf · hexane, where {MoO}8 represents one 1, three (2, linked, via the oxo group, to [Li(thf)3]+) and two (3a, linked by two [Li(thf)2]+).A mixed-valent variant of 3, (3b, with an additional[Li(thf)3]+ attached to S′), was also identified. The compounds model features pertinent to oxo-transferases containing the molybdopterin cofactor. 相似文献
67.
Yadhu?Kumar Ralf?Westram Sebastian?Behrens Bernhard?Fuchs Frank?Oliver?Gl?ckner Rudolf?Amann Harald?Meier Wolfgang?LudwigEmail author 《BMC bioinformatics》2005,6(1):61
Background
Taxon specific hybridization probes in combination with a variety of commonly used hybridization formats nowadays are standard tools in microbial identification. A frequently applied technology, fluorescence in situ hybridization (FISH), besides single cell identification, allows the localization and functional studies of the microbial community composition. Careful in silico design and evaluation of potential oligonucleotide probe targets is therefore crucial for performing successful hybridization experiments. 相似文献68.
Thomas?PresselEmail author Anas?Bouguecha Ute?Vogt Andrea?Meyer-Lindenberg Bernd-Arno?Behrens Ingo?Nolte Henning?Windhagen 《Biomedical engineering online》2005,4(1):66
After the publication of this work [1], we became aware of the fact that the frequency of the ultrasound transmitter that we used for determining the elastic moduli
of the trabecular bone specimens was not correctly specified. The oscillation frequency of the ultrasound transmitter was
2 MHz (and not 100 MHz as stated in our work) while we used a sampling rate of 100 MHz. In our publication, the oscillation
frequency and sampling rate were confounded. Therefore also the statement in the discussion that we might have determined
elastic moduli of trabecular bone tissue rather than the elastic properties of whole specimens because we used an ultrasound
frequency > 2 MHz is wrong and has to be omitted. 相似文献
69.
Pressel T Bouguecha A Vogt U Meyer-Lindenberg A Behrens BA Nolte I Windhagen H 《Biomedical engineering online》2005,4(1):17
Background
Studying mechanical properties of canine trabecular bone is important for a better understanding of fracture mechanics or bone disorders and is also needed for numerical simulation of canine femora. No detailed data about elastic moduli and degrees of anisotropy of canine femoral trabecular bone has been published so far, hence the purpose of this study was to measure the elastic modulus of trabecular bone in canine femoral heads by ultrasound testing and to assess whether assuming isotropy of the cancellous bone in femoral heads in dogs is a valid simplification. 相似文献70.
Hennecke G Nolte J Volkmer-Engert R Schneider-Mergener J Behrens S 《The Journal of biological chemistry》2005,280(25):23540-23548
The Escherichia coli periplasmic chaperone and peptidyl-prolyl isomerase (PPIase) SurA facilitates the maturation of outer membrane porins. Although the PPIase activity exhibited by one of its two parvulin-like domains is dispensable for this function, the chaperone activity residing in the non-PPIase regions of SurA, a sizable N-terminal domain and a short C-terminal tail, is essential. Unlike most cytoplasmic chaperones SurA is selective for particular substrates and recognizes outer membrane porins synthesized in vitro much more efficiently than other proteins. Thus, SurA may be specialized for the maturation of outer membrane proteins. We have characterized the substrate specificity of SurA based on its natural, biologically relevant substrates by screening cellulose-bound peptide libraries representing outer membrane proteins. We show that two features are critical for peptide binding by SurA: specific patterns of aromatic residues and the orientation of their side chains, which are found more frequently in integral outer membrane proteins than in other proteins. For the first time this sufficiently explains the capability of SurA to discriminate between outer membrane protein and non-outer membrane protein folding intermediates. Furthermore, peptide binding by SurA requires neither an active PPIase domain nor the presence of proline, indicating that the observed substrate specificity relates to the chaperone function of SurA. Finally, we show that SurA is capable of associating with the outer membrane. Together, our data support a model in which SurA is specialized to interact with non-native periplasmic outer membrane protein folding intermediates and to assist in their maturation from early to late outer membrane-associated steps. 相似文献