@article{WinterAndelovicKampfetal.2019,
  author    = {Winter, Patrick and Andelovic, Kristina and Kampf, Thomas and Gutjahr, Fabian Tobias and Heidenreich, Julius and Zernecke, Alma and Bauer, Wolfgang Rudolf and Jakob, Peter Michael and Herold, Volker},
  title     = {Fast self-navigated wall shear stress measurements in the murine aortic archusing radial 4D-phase contrast cardiovascular magnetic resonance at 17.6 T},
  series = {Journal of Cardiovascular Magnetic Resonance},
  volume    = {21},
  journal   = {Journal of Cardiovascular Magnetic Resonance},
  doi       = {10.1186/s12968-019-0566-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201120},
  pages     = {64},
  year      = {2019},
  abstract  = {Purpose 4D flow cardiovascular magnetic resonance (CMR) and the assessment of wall shear stress (WSS) are non-invasive tools to study cardiovascular risks in vivo. Major limitations of conventional triggered methods are the long measurement times needed for high-resolution data sets and the necessity of stable electrocardiographic (ECG) triggering. In this work an ECG-free retrospectively synchronized method is presented that enables accelerated high-resolution measurements of 4D flow and WSS in the aortic arch of mice. Methods 4D flow and WSS were measured in the aortic arch of 12-week-old wildtype C57BL/6 J mice (n = 7) with a radial 4D-phase-contrast (PC)-CMR sequence, which was validated in a flow phantom. Cardiac and respiratory motion signals were extracted from the radial CMR signal and were used for the reconstruction of 4D-flow data. Rigid motion correction and a first order B0 correction was used to improve the robustness of magnitude and velocity data. The aortic lumen was segmented semi-automatically. Temporally averaged and time-resolved WSS and oscillatory shear index (OSI) were calculated from the spatial velocity gradients at the lumen surface at 14 locations along the aortic arch. Reproducibility was tested in 3 animals and the influence of subsampling was investigated. Results Volume flow, cross-sectional areas, WSS and the OSI were determined in a measurement time of only 32 min. Longitudinal and circumferential WSS and radial stress were assessed at 14 analysis planes along the aortic arch. The average longitudinal, circumferential and radial stress values were 1.52 ± 0.29 N/m2, 0.28 ± 0.24 N/m2 and - 0.21 ± 0.19 N/m2, respectively. Good reproducibility of WSS values was observed. Conclusion This work presents a robust measurement of 4D flow and WSS in mice without the need of ECG trigger signals. The retrospective approach provides fast flow quantification within 35 min and a flexible reconstruction framework.},
  language  = {en}
}
@article{HofEmmerlingHackeretal.1982,
  author    = {Hof, H. and Emmerling, P. and Hacker, J{\"o}rg and Hughes, C.},
  title     = {The role of macrophages in primary and secondary infection of mice with Salmonella typhimurium},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-40248},
  year      = {1982},
  abstract  = {Elimination of macrophages with high-molecular dextran sulphate (OS) markedly impairs resistance of mice to primary infection with smooth, virulent strains of Salmonella typhimurium, whereas stimulation of this system by killed Bordetella pertussis organisms increases resistance. In infection with rough, avirulent strains of S. iyphimurium the elimination of macro phages was not followed by an essential loss of resistance, and it appears that other non-specific defence mechanisms, for example the complement system, may have compensated for the lack of macrophages. Macrophages, therefore, play an important role in defence during primary infection with virulent strains. In immunity to challenge infection with S. typhimurium, macrophages play an even more significant role. Treatment with OS completely removes immunity, and both humoral and cell-mediated immune mechanisms seem to require the participation of macrophages.},
  language  = {en}
}