@phdthesis{Meyer2013,
  author    = {Meyer, Sebastian},
  title     = {Model System for Correlation Phenomena in Reduced Dimensions - Gold-induced Atomic Chains on Germanium},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-77723},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2013},
  abstract  = {Atomic chains, often called nanowires, form in a self-organized process after the adsorption of metal atoms. These wires are spatially well confined representing a close approach of a true one-dimensional structure. The low-dimensional architecture thereby often leads to anisotropic electronic states with vanishing interchain interaction. In the presence of weak coupling to the substrate a one-dimensional metal can experience a phase transition according to Peierls into an insulating ground state upon temperature, which is accompanied by a periodic lattice distortion. Without any coupling a strict onedimensional regime is reached, where the common Fermi liquid description breaks down with the quasi-particles being replaced by collective excitations of spin and charge. This state is referred to as a Tomonaga-Luttinger liquid (TLL), which has been observed so far only in anisotropic bulk materials. An experimental fingerprint for both phenomena can be obtained from the electronic states close to the chemical potential, i.e. the Fermi energy. Using a semiconducting substrate provides the best observation conditions since any bulk projection onto the interesting bands is avoided. In case of Au/Ge(001) the growth of gold-induced chains is guided by the dimerized bare Ge (2×1) reconstruction yielding two different domains of wires rotated by 90° going from one terrace to the next by a single height step. The superior wetting capabilities of gold on germanium enables a complete coverage of the Ge(001) surface with longrange ordered wires. Their length scale and defect density is limited by the underlying substrate, for which a cleaning procedure is introduced based on wet-chemical etching followed by thermal dry oxidation. The band structure of Au/Ge(001) is investigated by angle-resolved photoelectron spectroscopy as a function of temperature. Two states are observed: a two-dimensional metallic state with hole-like dispersion and a one-dimensional electron pocket, whose band-integrated spectral function does not show the typical Fermi distribution at the chemical potential. Instead, a decrease of spectral weight applies following a power-law. This behavior can be well explained within the Tomonaga-Luttinger liquid theory which replaces the Fermi-Landau formalism in strictly one-dimensional systems. To enable theoretical modeling, a structural analysis was performed on the basis of surface x-ray diffraction (SXRD). From the in-plane scattering data a Patterson-map could be extracted leading to in-plane distances between gold atoms in the unit cell. This provides the first step towards a complete structural model and therefore towards a band structure calculation. First successful attempts have been made to manipulate the system by controlled adsorption of potassium. Here, an n-type doping effect is observed for submonolayer coverage whereas slightly increased coverages in combination with thermal energy lead to a new surface reconstruction.},
  subject      = {Nanodraht},
  language  = {en}
}
@article{MoratinIckrathScherzadetal.2021,
  author    = {Moratin, Helena and Ickrath, Pascal and Scherzad, Agmal and Meyer, Till Jasper and Naczenski, Sebastian and Hagen, Rudolf and Hackenberg, Stephan},
  title     = {Investigation of the immune modulatory potential of zinc oxide nanoparticles in human lymphocytes},
  series = {Nanomaterials},
  volume    = {11},
  journal   = {Nanomaterials},
  number    = {3},
  issn      = {2079-4991},
  doi       = {10.3390/nano11030629},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234016},
  year      = {2021},
  abstract  = {Zinc oxide nanoparticles (ZnO-NP) are commonly used for a variety of applications in everyday life. In addition, due to its versatility, nanotechnology supports promising approaches in the medical sector. NP can act as drug-carriers in the context of targeted chemo- or immunotherapy, and might also exhibit autonomous immune-modulatory characteristics. Knowledge of potential immunosuppressive or stimulating effects of NP is indispensable for the safety of consumers as well as patients. In this study, primary human peripheral blood lymphocytes of 9 donors were treated with different sub-cytotoxic concentrations of ZnO-NP for the duration of 1, 2, or 3 days. Flow cytometry was performed to investigate changes in the activation profile and the proportion of T cell subpopulations. ZnO-NP applied in this study did not induce any significant alterations in the examined markers, indicating their lack of impairment in terms of immune modulation. However, physicochemical characteristics exert a major influence on NP-associated bioactivity. To allow a precise simulation of the complex molecular processes of immune modulation, a physiological model including the different components of an immune response is needed.},
  language  = {en}
}
@article{StegnervanEeuwijkAngayetal.2017,
  author    = {Stegner, David and van Eeuwijk, Judith M.M. and Angay, Oğuzhan and Gorelashvili, Maximilian G. and Semeniak, Daniela and Pinnecker, J{\"u}rgen and Schmithausen, Patrick and Meyer, Imke and Friedrich, Mike and D{\"u}tting, Sebastian and Brede, Christian and Beilhack, Andreas and Schulze, Harald and Nieswandt, Bernhard and Heinze, Katrin G.},
  title     = {Thrombopoiesis is spatially regulated by the bone marrow vasculature},
  series = {Nature Communications},
  volume    = {8},
  journal   = {Nature Communications},
  number    = {127},
  doi       = {10.1038/s41467-017-00201-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170591},
  year      = {2017},
  abstract  = {In mammals, megakaryocytes (MKs) in the bone marrow (BM) produce blood platelets, required for hemostasis and thrombosis. MKs originate from hematopoietic stem cells and are thought to migrate from an endosteal niche towards the vascular sinusoids during their maturation. Through imaging of MKs in the intact BM, here we show that MKs can be found within the entire BM, without a bias towards bone-distant regions. By combining in vivo two-photon microscopy and in situ light-sheet fluorescence microscopy with computational simulations, we reveal surprisingly slow MK migration, limited intervascular space, and a vessel-biased MK pool. These data challenge the current thrombopoiesis model of MK migration and support a modified model, where MKs at sinusoids are replenished by sinusoidal precursors rather than cells from a distant periostic niche. As MKs do not need to migrate to reach the vessel, therapies to increase MK numbers might be sufficient to raise platelet counts.},
  language  = {en}
}
@article{StanglRauchRauhetal.2021,
  author    = {Stangl, Stephanie and Rauch, Sebastian and Rauh, J{\"u}rgen and Meyer, Martin and M{\"u}ller-Nordhorn, Jacqueline and Wildner, Manfred and W{\"o}ckel, Achim and Heuschmann, Peter U.},
  title     = {Disparities in Accessibility to Evidence-Based Breast Cancer Care Facilities by Rural and Urban Areas in Bavaria, Germany},
  series = {Cancer},
  volume    = {127},
  journal   = {Cancer},
  number    = {13},
  doi       = {10.1002/cncr.33493},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239854},
  pages     = {2319 -- 2332},
  year      = {2021},
  abstract  = {Background Breast cancer (BC), which is most common in elderly women, requires a multidisciplinary and continuous approach to care. With demographic changes, the number of patients with chronic diseases such as BC will increase. This trend will especially hit rural areas, where the majority of the elderly live, in terms of comprehensive health care. Methods Accessibility to several cancer facilities in Bavaria, Germany, was analyzed with a geographic information system. Facilities were identified from the national BC guideline and from 31 participants in a proof-of-concept study from the Breast Cancer Care for Patients With Metastatic Disease registry. The timeframe for accessibility was defined as 30 or 60 minutes for all population points. The collection of address information was performed with different sources (eg, a physician registry). Routine data from the German Census 2011 and the population-based Cancer Registry of Bavaria were linked at the district level. Results Females from urban areas (n = 2,938,991 [ie, total of females living in urban areas]) had a higher chance for predefined accessibility to the majority of analyzed facilities in comparison with females from rural areas (n = 3,385,813 [ie, total number of females living in rural areas]) with an odds ratio (OR) of 9.0 for cancer information counselling, an OR of 17.2 for a university hospital, and an OR of 7.2 for a psycho-oncologist. For (inpatient) rehabilitation centers (OR, 0.2) and genetic counselling (OR, 0.3), women from urban areas had lower odds of accessibility within 30 or 60 minutes. Conclusions Disparities in accessibility between rural and urban areas exist in Bavaria. The identification of underserved areas can help to inform policymakers about disparities in comprehensive health care. Future strategies are needed to deliver high-quality health care to all inhabitants, regardless of residence.},
  language  = {en}
}
@article{HartrampfLapaSerflingetal.2021,
  author    = {Hartrampf, Philipp E. and Lapa, Constantin and Serfling, Sebastian E. and Buck, Andreas K. and Seitz, Anna Katharina and Meyer, Philipp T. and Ruf, Juri and Michalski, Kerstin},
  title     = {Development of Discordant Hypermetabolic Prostate Cancer Lesions in the Course of [\(^{177}\)Lu]PSMA Radioligand Therapy and Their Possible Influence on Patient Outcome},
  series = {Cancers},
  volume    = {13},
  journal   = {Cancers},
  number    = {17},
  issn      = {2072-6694},
  doi       = {10.3390/cancers13174270},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245168},
  year      = {2021},
  abstract  = {Simple Summary Discordant FDG-positive but PSMA-negative (FDG+/PSMA-) metastases constitute a negative prognostic marker of overall survival in patients undergoing PSMA radioligand therapy (RLT). The aim of this analysis was to investigate the prognostic implications of new FDG+/PSMA- lesions, which occur during or after PSMA RLT. In a retrospective bicentric analysis of 32 patients undergoing PSMA RLT and follow-up dual tracer staging with PSMA and FDG PET/CT, FDG+/PSMA- lesions occurred in a limited number of patients. However, the presence of FDG+/PSMA- lesions appears not to have a significant impact on the OS, but further studies are needed to establish the clinical relevance of such lesions. Abstract Introduction: Positron emission tomography/computer tomography (PET/CT) targeting the prostate-specific membrane antigen (PSMA) is crucial for the assessment of adequate PSMA expression in patients with metastatic castration-resistant prostate cancer (mCRPC) prior to PSMA radioligand therapy (PSMA RLT). Moreover, initial dual tracer staging using combined PSMA and [\(^{18}\)F]fluorodeoxyglucose (FDG) PET/CT provides relevant information, since discordant FDG-positive but PSMA-negative (FDG+/PSMA-) lesions constitute a negative prognostic marker of overall survival (OS) after PSMA RLT. However, little is known about the prognostic implications of dual tracer imaging for restaging at follow-up. The aim of this analysis was to investigate the prognostic implications of new FDG+/PSMA- lesions during or after PSMA RLT. Methods: This bicentric analysis included 32 patients with mCRPC who underwent both FDG and PSMA PET/CT imaging after two or four cycles of PSMA RLT. Patients with FDG+/PSMA- lesions prior to PSMA RLT were not considered. The presence of FDG+/PSMA- lesions was assessed with follow-up dual tracer imaging of patients after two or four cycles of PSMA RLT. Patients with at least one new FDG+/PSMA- lesion were compared to patients without any FDG+/PSMA- lesions at the respective time points. A log-rank analysis was used to assess the difference in OS between subgroups. Results: After two cycles of PSMA RLT, four of 32 patients (13\%) had FDG+/PSMA- metastases. No significant difference in OS was observed (p = 0.807), as compared to patients without FDG+/PSMA- lesions. Follow-up dual tracer imaging after the 4th cycle of PSMA RLT was available in 18 patients. Of these, four patients presented with FDG+/PSMA- findings (n = 2 already after two cycles). After the fourth cycle of PSMA RLT, no significant difference in OS was observed between patients with and without FDG+/PSMA- lesions (p = 0.442). Conclusion: This study shows that FDG+/PSMA- lesions develop in a limited number of patients undergoing PSMA RLT. Further studies are needed to establish the clinical relevance of such lesions.},
  language  = {en}
}