TY  - THES
A1  - Koster, Joachim
T1  - Polarisations-sensitive Resonanz-CARS- und Resonanz-Raman-Spektroskopie an metallfreien Porphyrinen
T1  - Polarization-sensitive resonance CARS and resonance Raman spectroscopy on free-base porphyrins
N2  - Es werden in dieser Arbeit Raman-spektroskopische Untersuchungen an metallfreien Porphyrinen in verdünnter Lösung vorgestellt. Dabei werden Laseranregungswellenlängen eingesetzt, die mit elektronischen Resonanzen der Porphyrine zusammenfallen. Die Ausnutzung von Resonanz-Effekten hat zum einen den Vorteil, dass gewisse Raman-Banden, je nach der Symmetrie der zugrunde liegenden Molekülschwingung, eine deutliche Intensitätsverstärkung erfahren können, was den Nachweis auch geringer Probenkonzentrationen ermöglicht. Zum anderen sind anhand der Banden-Parameter Rückschlüsse auf die exakte Molekülsymmetrie möglich. Im Vergleich zu Metalloporphyrinen sind für metallfreie Porphyrine bisher nur wenige Daten aus resonanten Raman-Spektren bekannt. Ein Grund hierfür ist, dass letztere ein höheres Maß an Fluoreszenz zeigen, die die Raman-Signale überlagert. Während bei Laseranregungen im Bereich hochenergetischer elektronischer Absorptionen der Porphyrine (B-Banden-Region) die klassische spontane Raman-Spektroskopie noch angewendet werden kann, ist dies im Bereich niederenergetischer Absorptionen (Q-Banden-Region) meist nicht mehr möglich. Um auch Anregungen in der Q-Banden-Region zu verwirklichen, wird daher in dieser Arbeit von der kohärenten anti-Stokesschen Raman-Streuung (coherent anti-Stokes Raman scattering, CARS) Gebrauch gemacht. Die CARS-Spektroskopie ermöglicht es, das Fluoreszenzproblem zu umgehen, und bietet zudem noch weitere Vorteile, z. B. bezüglich der Unterscheidbarkeit spektral benachbarter Banden sowie bezüglich der Bestimmung symmetrierelevanter Parameter. Raman-Banden-Parameter aus Q-Banden-CARS-Spektren konnten hier für vier metallfreie Porphyrine, die sich im Substitutionsmuster an den beta-Kohlenstoffatomen des Tetrapyrrol-Makrozyklus unterscheiden, erhalten werden. Die CARS-Parameter, in Kombination mit Parametern aus spontanen B-Banden-Raman-Spektren sowie mit quantenchemisch berechneten Schwingungsvektoren, ließen den Schluss zu, dass Symmetrieunterschiede zwischen den Makrozyklen dieser Moleküle zwar gering, aber durchaus feststellbar sind. Desweiteren konnten durch die niederenergetische Anregung für die metallfreien Porphyrine spezifische Resonanzeffekte nachgewiesen werden, die z. T. von den für Metalloporphyrine bekannten Mustern abweichen.
N2  - In this thesis, Raman spectroscopic investigations on free-base porphyrins in dilute solution are presented. For this, laser excitation wavelengths are employed, that coincide with electronic resonances of the porphyrins. Exploiting resonance effects provides, on one hand, the advantage, that certain Raman bands, depending on the symmetry of the corresponding molecular vibration, can experience a significant intensity enhancement, which facilitates the detection of even small sample concentrations. On the other hand, through the band parameters conclusions about the exact molecular symmetry are possible. Compared to metalloporphyrins, for free-base porphyrins only few data from resonant Raman spectra are known. One reason for that is, that the latter exhibit a higher amount of fluorescence which overlays the Raman signals. While with laser excitation in the high energy electronic absorption range of porphyrins (B band region) the classical spontaneous Raman spectroscopy is still applicable, it often fails in the low energy absorption range (Q band region). Therefore, to also perform excitations in the Q band region, in this work it is made use of coherent anti-Stokes Raman scattering (CARS). The CARS spectroscopy allows to circumvent the fluorescence problem and offers additional advantages, e. g. concerning the discrimination of spectrally closely spaced bands and concerning the determination of symmetry relevant parameters. Raman band parameters from Q band CARS spectra could be obtained here for four free-base porphyrins, which differ in the substitution pattern at the beta carbon atoms of the tetrapyrrole macrocycle. The CARS parameters, in combination with parameters from spontaneous B band Raman spectra as well as with quantum chemically calculated vibrational vectors, allowed the conclusion, that differences in symmetry between the macrocycles of these molecules are small, but nevertheless detectable. Further, the low energy excitation revealed specific resonance effects for free-base porphyrins, that in part differ from the patterns known for metallo porphyrins.
KW  - Porphyrine
KW  - CARS-Spektroskopie
KW  - Raman-Spektroskopie
KW  - metallfreie Porphyrine
KW  - beta-Substitution
KW  - kohärente anti-Stokessche Raman-Streuung
KW  - Resonanz-Raman
KW  - free-base porphyrins
KW  - beta substitution
KW  - coherent anti-Stokes Raman scattering
KW  - resonance Raman
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-20358
ER  - 
TY  - JOUR
A1  - Koster, Stefanie
A1  - Gurumurthy, Rajendra Kumar
A1  - Kumar, Naveen
A1  - Prakash, Pon Ganish
A1  - Dhanraj, Jayabhuvaneshwari
A1  - Bayer, Sofia
A1  - Berger, Hilmar
A1  - Kurian, Shilpa Mary
A1  - Drabkina, Marina
A1  - Mollenkopf, Hans-Joachim
A1  - Goosmann, Christian
A1  - Brinkmann, Volker
A1  - Nagel, Zachary
A1  - Mangler, Mandy
A1  - Meyer, Thomas F.
A1  - Chumduri, Cindrilla
T1  - Modelling Chlamydia and HPV co-infection in patient-derived ectocervix organoids reveals distinct cellular reprogramming
JF  - Nature Communications
N2  - Coinfections with pathogenic microbes continually confront cervical mucosa, yet their implications in pathogenesis remain unclear. Lack of in-vitro models recapitulating cervical epithelium has been a bottleneck to study coinfections. Using patient-derived ectocervical organoids, we systematically modeled individual and coinfection dynamics of Human papillomavirus (HPV)16 E6E7 and Chlamydia, associated with carcinogenesis. The ectocervical stem cells were genetically manipulated to introduce E6E7 oncogenes to mimic HPV16 integration. Organoids from these stem cells develop the characteristics of precancerous lesions while retaining the self-renewal capacity and organize into mature stratified epithelium similar to healthy organoids. HPV16 E6E7 interferes with Chlamydia development and induces persistence. Unique transcriptional and post-translational responses induced by Chlamydia and HPV lead to distinct reprogramming of host cell processes. Strikingly, Chlamydia impedes HPV-induced mechanisms that maintain cellular and genome integrity, including mismatch repair in the stem cells. Together, our study employing organoids demonstrates the hazard of multiple infections and the unique cellular microenvironment they create, potentially contributing to neoplastic progression.
KW  - Chlamydia
KW  - HPV
KW  - cellular reprogramming
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301349
VL  - 13
IS  - 1
ER  - 
TY  - JOUR
A1  - Gröbner, Susanne N.
A1  - Worst, Barbara C.
A1  - Weischenfeldt, Joachim
A1  - Buchhalter, Ivo
A1  - Kleinheinz, Kortine
A1  - Rudneva, Vasilisa A.
A1  - Johann, Pascal D.
A1  - Balasubramanian, Gnana Prakash
A1  - Segura-Wang, Maia
A1  - Brabetz, Sebastian
A1  - Bender, Sebastian
A1  - Hutter, Barbara
A1  - Sturm, Dominik
A1  - Pfaff, Elke
A1  - Hübschmann, Daniel
A1  - Zipprich, Gideon
A1  - Heinold, Michael
A1  - Eils, Jürgen
A1  - Lawerenz, Christian
A1  - Erkek, Serap
A1  - Lambo, Sander
A1  - Waszak, Sebastian
A1  - Blattmann, Claudia
A1  - Borkhardt, Arndt
A1  - Kuhlen, Michaela
A1  - Eggert, Angelika
A1  - Fulda, Simone
A1  - Gessler, Manfred
A1  - Wegert, Jenny
A1  - Kappler, Roland
A1  - Baumhoer, Daniel
A1  - Stefan, Burdach
A1  - Kirschner-Schwabe, Renate
A1  - Kontny, Udo
A1  - Kulozik, Andreas E.
A1  - Lohmann, Dietmar
A1  - Hettmer, Simone
A1  - Eckert, Cornelia
A1  - Bielack, Stefan
A1  - Nathrath, Michaela
A1  - Niemeyer, Charlotte
A1  - Richter, Günther H.
A1  - Schulte, Johannes
A1  - Siebert, Reiner
A1  - Westermann, Frank
A1  - Molenaar, Jan J.
A1  - Vassal, Gilles
A1  - Witt, Hendrik
A1  - Burkhardt, Birgit
A1  - Kratz, Christian P.
A1  - Witt, Olaf
A1  - van Tilburg, Cornelis M.
A1  - Kramm, Christof M.
A1  - Fleischhack, Gudrun
A1  - Dirksen, Uta
A1  - Rutkowski, Stefan
A1  - Frühwald, Michael
A1  - Hoff, Katja von
A1  - Wolf, Stephan
A1  - Klingebeil, Thomas
A1  - Koscielniak, Ewa
A1  - Landgraf, Pablo
A1  - Koster, Jan
A1  - Resnick, Adam C.
A1  - Zhang, Jinghui
A1  - Liu, Yanling
A1  - Zhou, Xin
A1  - Waanders, Angela J.
A1  - Zwijnenburg, Danny A.
A1  - Raman, Pichai
A1  - Brors, Benedikt
A1  - Weber, Ursula D.
A1  - Northcott, Paul A.
A1  - Pajtler, Kristian W.
A1  - Kool, Marcel
A1  - Piro, Rosario M.
A1  - Korbel, Jan O.
A1  - Schlesner, Matthias
A1  - Eils, Roland
A1  - Jones, David T. W.
A1  - Lichter, Peter
A1  - Chavez, Lukas
A1  - Zapatka, Marc
A1  - Pfister, Stefan M.
T1  - The landscape of genomic alterations across childhood cancers
JF  - Nature
N2  - Pan-cancer analyses that examine commonalities and differences among various cancer types have emerged as a powerful way to obtain novel insights into cancer biology. Here we present a comprehensive analysis of genetic alterations in a pan-cancer cohort including 961 tumours from children, adolescents, and young adults, comprising 24 distinct molecular types of cancer. Using a standardized workflow, we identified marked differences in terms of mutation frequency and significantly mutated genes in comparison to previously analysed adult cancers. Genetic alterations in 149 putative cancer driver genes separate the tumours into two classes: small mutation and structural/copy-number variant (correlating with germline variants). Structural variants, hyperdiploidy, and chromothripsis are linked to TP53 mutation status and mutational signatures. Our data suggest that 7–8% of the children in this cohort carry an unambiguous predisposing germline variant and that nearly 50% of paediatric neoplasms harbour a potentially druggable event, which is highly relevant for the design of future clinical trials.
KW  - cancer genomics
KW  - oncogenesis
KW  - paediatric cancer
KW  - predictive markers
KW  - translational research
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229579
VL  - 555
ER  -