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111.
Andreas Otto Jan Maarten van Dijl Michael Hecker Dörte Becher 《International journal of medical microbiology : IJMM》2014,304(2):110-120
Staphylococcus aureus is a Gram-positive commensal bacterium that is regarded as a major threat for modern health care systems. This relates both to the ability of S. aureus to overcome antibiotic therapy by developing high-level resistance against multiple antibiotics and this bacterium's extensive arsenal of virulence factors. Understanding the mechanisms of resistance and functional studies on stress and starvation responses are the main goals of proteomics in staphylococcal research. This review high-lights recent advances in gel-based and gel-free proteomics analyses of S. aureus and pinpoints the importance of location-specific proteomics studies targeting the cytosol, the membrane, the cell surface and the extracellular milieu in combination with integrated global proteome studies. Emerging hot topics in staphylococcal proteomics are discussed with special focus on in vivo proteomics, membrane vesicles, biofilm formation and the acquisition of absolute proteome data for systems biological modeling approaches. 相似文献
112.
Alban Flachot Arash Akbarinia Heiko H. Schütt Roland W. Fleming Felix A. Wichmann Karl R. Gegenfurtner 《Journal of vision》2022,22(4)
Color constancy is our ability to perceive constant colors across varying illuminations. Here, we trained deep neural networks to be color constant and evaluated their performance with varying cues. Inputs to the networks consisted of two-dimensional images of simulated cone excitations derived from three-dimensional (3D) rendered scenes of 2,115 different 3D shapes, with spectral reflectances of 1,600 different Munsell chips, illuminated under 278 different natural illuminations. The models were trained to classify the reflectance of the objects. Testing was done with four new illuminations with equally spaced CIEL*a*b* chromaticities, two along the daylight locus and two orthogonal to it. High levels of color constancy were achieved with different deep neural networks, and constancy was higher along the daylight locus. When gradually removing cues from the scene, constancy decreased. Both ResNets and classical ConvNets of varying degrees of complexity performed well. However, DeepCC, our simplest sequential convolutional network, represented colors along the three color dimensions of human color vision, while ResNets showed a more complex representation. 相似文献
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Color Doppler Visualization of Intramyocardial Coronary Arteries Using a New Echo System: Effect of Contrast Enhancement and Vasodilation 总被引:9,自引:0,他引:9
Garcia Del Rio C Taylor GW Nanda NC Agrawal DI Agrawal GG Carvalho C Espinal M Becher H 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):645-650
Utilizing a new echocardiographic system, intramyocardial coronary arteries could be demonstrated by color Doppler in a small number of open chest animals. Both intravenous and intracoronary injections of a contrast agent (Levovist) resulted in significant enhancement of color flow signals with an increase in the length, width, and the number of these vessels. Similar results were obtained with intravenous infusion and direct intracoronary injections of a vasodilator (adenosine). 相似文献
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Jana Schmitzer Carolin Strobel Ronald Blechschmidt Adrian Tappe Heiko Peuscher 《Journal of diabetes science and technology》2022,16(1):61
Background:Numerical simulations, also referred to as in silico trials, are nowadays the first step toward approval of new artificial pancreas (AP) systems. One suitable tool to run such simulations is the UVA/Padova Type 1 Diabetes Metabolic Simulator (T1DMS). It was used by Toffanin et al. to provide data about safety and efficacy of AndroidAPS, one of the most wide-spread do-it-yourself AP systems. However, the setup suffered from slow simulation speed. The objective of this work is to speed up simulation by implementing the algorithm directly in MATLAB®/Simulink®.Method:Firstly, AndroidAPS is re-implemented in MATLAB® and verified. Then, the function is incorporated into T1DMS. To evaluate the new setup, a scenario covering 2 days in real time is run for 30 virtual patients. The results are compared to those presented in the literature.Results:Unit tests and integration tests proved the equivalence of the new implementation and the original AndroidAPS code. Simulation of the scenario required approximately 15 minutes, corresponding to a speed-up factor of roughly 1000 with respect to real time. The results closely resemble those presented by Toffanin et al. Discrepancies were to be expected because a different virtual population was considered. Also, some parameters could not be extracted from and harmonized with the original setup.Conclusions:The new implementation facilitates extensive in silico trials of AndroidAPS due to the significant reduction of runtime. This provides a cheap and fast means to test new versions of the algorithm before they are shared with the community. 相似文献
116.
Iben Stokholm Nicole Fischer Christine Baechlein Alexander Postel Anders Galatius Line Anker Kyhn Charlotte Bie Thstesen Sara Persson Ursula Siebert Morten Tange Olsen Paul Becher 《Viruses》2022,14(1)
Pestiviruses are widespread pathogens causing severe acute and chronic diseases among terrestrial mammals. Recently, Phocoena pestivirus (PhoPeV) was described in harbour porpoises (Phocoena phocoena) of the North Sea, expanding the host range to marine mammals. While the role of the virus is unknown, intrauterine infections with the most closely related pestiviruses— Bungowannah pestivirus (BuPV) and Linda virus (LindaV)—can cause increased rates of abortions and deaths in young piglets. Such diseases could severely impact already vulnerable harbour porpoise populations. Here, we investigated the presence of PhoPeV in 77 harbour porpoises, 277 harbour seals (Phoca vitulina), grey seals (Halichoerus grypus) and ringed seals (Pusa hispida) collected in the Baltic Sea region between 2002 and 2019. The full genome sequence of a pestivirus was obtained from a juvenile female porpoise collected along the coast of Zealand in Denmark in 2011. The comparative Bayesian phylogenetic analyses revealed a close relationship between the new PhoPeV sequence and previously published North Sea sequences with a recent divergence from genotype 1 sequences between 2005 and 2009. Our findings provide further insight into the circulation of PhoPeV and expand the distribution from the North Sea to the Baltic Sea region with possible implications for the vulnerable Belt Sea and endangered Baltic Proper harbour porpoise populations. 相似文献
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119.
Simon Pecha Tibor Ziegelhoeffer Yalin Yildirim Yeong-Hoon Choi Stephan Willems Hermann Reichenspurner Heiko Burger Samer Hakmi 《Interactive Cardiovascular and Thoracic Surgery》2021,32(3):402
OBJECTIVESTransvenous lead extraction using mechanical rotational- or laser sheaths is an established procedure. Lead dwell time has been recognized as a risk factor for extraction failure and procedure-related complications. We therefore investigated the safety and efficacy of transvenous extraction of leads with an implant duration of more than 10 years.Open in a separate windowMETHODSBetween January 2013 and March 2017, a total of 403 patients underwent lead extraction in 2 high-volume lead extraction centres. One hundred and fifty-four patients with extraction of at least 1 lead aged over 10 years were included in this analysis. Laser lead extraction was the primary extraction method, with additional use of mechanical rotational sheaths or femoral snares, if necessary. All procedural- and patient-based data were collected into a database and retrospectively analysed.RESULTSMean patient’s age was 65.8 ± 15.8 years, 68.2% were male. Three hundred and sixty-two leads had to be extracted. The mean lead dwell time of treated leads was 14.0 ± 6.1 years. Complete procedural success was achieved in 91.6% of cases, while clinical success was achieved in 96.8%. Failure of extraction occurred in 3.2%. Leads that could not be completely removed had a significantly longer lead dwell time (18.2 vs 13.2 years; P = 0.016). Additional mechanical rotational sheaths or femoral snares were used in 26 (16.9%) patients. Overall complication rate was 4.6%, including 5 (3.3%) major and 2 (1.3%) minor complications. There was no procedure-related mortality.CONCLUSIONSTransvenous lead extraction in leads aged over 10 years is safe and effective when performed in specialized centres and with use of multiple tools and techniques. Leads that could not be completely extracted had a statistically significant longer lead dwell time. 相似文献
120.