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Einfluß der Dialysetherapie auf den Genomschaden von Nierenpatienten in einer prospektiven Studie
(2007)
Patienten mit terminaler Niereninsuffizienz haben im Vergleich zur Normalbevölkerung eine deutlich erhöhte Inzidenz maligner Erkrankungen. Frühere Untersuchungen zeigten, dass periphere Blutlymphozyten dieser Patienten einen höheren genetischen Schaden aufweisen, wodurch das Risiko einer malignen Entartung steigt. In dieser Arbeit wurde der genetische Schaden mithilfe zweier Testverfahren, Comet Assay und Mikrokerntest, untersucht. Es handelte sich um eine prospektive Studie mit zwei Patientenkollektiven. Die erste Gruppe bestand aus Patienten, die aufgrund einer terminalen Niereninsuffizienz innerhalb der nächsten Monate eine Dialysetherapie mittels konventioneller Hämodialyse beginnen mußten. Die zweite Gruppe bildeten Dialysepatienten, die im Verlauf von konventioneller Dialyse auf Hämodiafiltration umgestellt wurden. Bei allen Patienten wurde der genetische Schaden der peripheren Blutlymphozyten in den Monaten vor und nach Therapiebeginn bzw. Therapieumstellung regelmäßig untersucht. Unsere Ergebnisse zeigen, dass 4 der 10 Prädialysepatienten nach Beginn der Dialyse einen niedrigeren genetischen Schaden hatten, 2 Patienten hatten unterschiedliche Werte in Comet Assay und Mikrokerntest und bei 2 Patienten ergab sich im Verlauf eine höhere DNA-Schädigung. Die verbliebenen 2 Patienten mußten aufgrund einer konstant bleibenden Niereninsuffizienz nicht mit der Dialysetherapie beginnen. Bei Zusammenfassung aller Einzelwerte zeigte sich, dass das Kollektiv der Prädialysepatienten insgesamt vom Beginn der Behandlung profitiert hat. In der Gruppe der Dialysepatienten hatte 2 von 7 Patienten nach Umstellung auf Hämodiafiltration eine geringere DNA-Schädigung, 2 Patienten zeigten unterschiedliche Ergebnisse im Comet Assay und Mikrokerntest und 2 weitere Patienten wiesen eine höheren genetischen Schaden in den Lymphozyten auf. Ein Patient konnte bei fehlenden Vorwerten nicht berücksichtigt werden. Im Gruppenvergleich zeigte sich für alle Dialysepatienten ein gleichbleibender DNA-Schaden, gemessen mithilfe des Comet Assays bei leicht erhöhten Mikrokernraten. Jedoch hatte sich die Zellproliferation ebenfalls etwas verbessert. Zusammenfassend ergibt sich somit in beiden Gruppen kein eindeutiges Ergebnis, woraus neue Therapieempfehlungen für Patienten mit terminaler Niereninsuffizienz abzuleiten wären. Um weiter Einflußvariablen auf die Höhe des genetischen Schadens festzustellen, sind weiter Untersuchungen mit größeren Patientenkollektiven erforderlich.
The aim of the present study was to design different dosage forms as carrier systems to deliver sorafenib to the lung of BXB-23 transgenic mice using different routes of administration. Three dosage forms were used one of them was an oil-in-water emulsion and the oral route was chosen for this experiment. The other delivery system was a liposome preparation for intratracheal instillation. In this case the oral route was considered as a control experiment. The last dosage form was PLGA microspheres. Before sorafenib administration it was important to develop a HPLC method to assess sorafenib absorption after its administration and to determine its concentrations in mouse serum. The HPLC method allowed sorafenib quantification in small volumes (30 µl) of mouse serum and tissues. The developed HPLC method was validated resulting in satisfactory selectivity, good linearity, good accuracy and precision over the concentration range examined. Sorafenib was successfully incorporated in a fat emulsion (o/w) using a traditional method resulting in a white homogenous emulsion and no particle aggregation was observed. Sorafenib exhibited antitumor activity on the lung adenoma in BXB-23 transgenic mice when administered orally (2 mg sorafenib per mouse) in the emulsion preparation. The determined effect was an approximately 29 % reduction in the tumor area of the adenoma foci and a proliferation reduction. In order to improve the pharmacological effects of sorafenib on the lung adenoma in BXB-23 mice, the targeting of sorafenib directly to the site of action (the lung) was an attractive concept. For this purpose the intratracheal route was used. Since sorafenib administration by instillation required incorporation of sorafenib in a dosage form suitable for its lipophilic nature, a liposome suspension was the second dosage form used. A lyophilization method was employed for sorafenib liposome preparation utilizing dilauroylphosphatidylcholine (DLPC) which is safe and tolerable for the lung. Incorporation of sorafenib in the liposomes did not influence the particle size and its distribution. The sorafenib liposomes showed high encapsulation efficiency, good stability at 4 °C for one month and satisfactory in vitro release properties and inhibited Raf-1 mediated activation of ERK in cell culture assay. In a pharmacokinetic experiment sorafenib loaded liposomes were instilled directly into the lung. The results revealed that a significant level of sorafenib was achieved in the lung tissues after 2 hours and then reduced after 48 h and remained nearly constant for one week. On the other hand, only traces of sorafenib were found in the mice serum up to 48 h. Subsequently, the pharmacological activity of sorafenib (1 mg per mouse) was studied when delivered in a liposomal suspension intratracheally to treat the lung adenoma of BXB-23 mice. The data of this experiment demonstrated that sorafenib intratracheal instillation resulted in a reduction of tumor area of adenoma foci (67 %) and an elevation of the percent of apoptotic cells. In contrast, prolongation of the treatment period did not further enhance sorafenib activity on the lung adenoma. This previous finding suggested a development of multidrug resistance (MDR) by the adenoma foci cells against sorafenib instillation, which was examined by immunohistochemistry staining. The percent of MDR positive cells was higher after two and three weeks sorafenib liposome instillation treatment than that after one week treatment. The last dosage form used for sorafenib was microspheres, which were prepared by emulsion-diffusion-evaporation method using biodegradable PLGA 50:50 resulting in a white lyophilized powder. The system was characterized physicochemically and revealed a good microspheres yield, high encapsulation efficiency, a homogenous particle size distribution and slow in vitro release of sorafenib. The other strategy studied in the present research project was gene delivery to target the lung bearing tumor of BXB-23 mice using a non-viral vector (polyethylenimine). Polyethylenimine (PEI) was used to investigate its efficiency in transfecting lung bearing tumor of BXB-23 mice model and its ability to transfect the adenoma foci cells. LacZ, which encodes Beta-galactosidase was used in the present study as a reporter gene and was complexed with PEI before delivered intravenously. A high LacZ expression in the alveolar region with some expression in the adenoma foci was observed. On contrary, a low LacZ expression in the alveoli and in the adenoma foci was achieved after instillation of the same polyplex intratracheally.
Diese Dissertation enthält eine Edition und eine annotierte Übersetzung des dem Bhasa zugeschriebenen Sanskrit-Schauspiels "Pratijnayaugandharayana". Die Edition beruht auf zehn Manuskripten, von denen bisherige Ausgaben nur drei verwendet hatten. Um Zusammenhänge zwischen den Manuskripten sichtbar zu machen, und so deren jeweiligen Wert besser beurteilen zu können, werden quantitative Methoden verwendet. In diesem Zusammenhang wird die effektive Verwendung von EDV für die Veröffentlichung von Sanskrit-Schauspielen reflektiert. Die vorgestellte Herangehensweise ermöglichte auch die automatische Erstellung des als Anhang enthaltenen Index aller in dem Schauspiel vorkommenden Sanskrit- und Prakrit-Wortformen.
Diese Arbeit versucht, die wirtschaftliche Bedeutung der globalen Erwärmung zu erklären und die Lösung dieses Problems zu finden. Die globale Erwärmung als länderübergreifendes Problems kann durch das marktwirtschaftliche Preissystem gelöst werden, besonders durch den internationalen Handel der Schadstoffemission. Hierbei wird die dezentrale Lösungsprinzip betont. Die globale Erwärmung und Politik für die Lösung dieses Problem sind dauerhaft. Daher wird das intertemporale Wachstumsmodell zur Berechnung des Gewinns und der Kosten der Politik verlangt. Dabei wird ein Prinzip besagt, dass jede Generation verantwortlich auf ihre Generation ist. In dieser Arbeit wird versucht, die optimale Handelspolitik und die Kyoto-Politik zu vergleichen.
Despite its precise agreement with the experiment, the validity of the standard model (SM) of elementary particle physics is ensured only up to a scale of several hundred GeV so far. Even more, the inclusion of gravity into an unifying theory poses a problem which cannot be solved by ordinary quantum field theory (QFT). String theory, which is the most popular ansatz for a unified theory, predicts QFT on noncommutative space-time as a low energy limit. Nevertheless, independently of the motivation given by string theory, the nonlocality inherent to noncommutative QFT opens up the possibility for the inclusion of gravity. There are no theoretical predictions for the energy scale Lambda_NC at which noncommutative effects arise and it can be assumed to lie in the TeV range, which is the energy range probed by the next generation of colliders. Within this work we study the phenomenological consequences of a possible realization of QFT on noncommutative space-time relying on this assumption. The motivation for this thesis was given by the gap in the range of phenomenological studies of noncommutative effects in collider experiments, due to the absence in the literature of Large Hadron Collider (LHC) studies regarding noncommutative QFTs. In the first part we thus performed a phenomenological analysis of the hadronic process pp -> Z gamma -> l^+l^- gamma at the LHC and of electron-positron pair annihilation into a Z boson and a photon at the International Linear Collider (ILC). The noncommutative extension of the SM considered within this work relies on two building blocks: the Moyal-Weyl star-product of functions on ordinary space-time and the Seiberg-Witten maps. The latter relate the ordinary fields and parameters to their noncommutative counterparts such that ordinary gauge transformations induce noncommutative gauge transformations. This requirement is expressed by a set of inhomogeneous differential equations (the gauge equivalence equations) which are solved by the Seiberg-Witten maps order by order in the noncommutative parameter Theta. Thus, by means of the Moyal-Weyl star-product and the Seiberg-Witten maps a noncommutative extension of the SM as an effective theory as expansion in powers of Theta can be achieved, providing the framework of our phenomenological studies. A consequence of the noncommutativity of space-time is the violation of rotational invariance with respect to the beam axis. This effect shows up in the azimuthal dependence of cross sections, which is absent in the SM as well as in other models beyond the SM. Thus, the azimuthal dependence of the cross section is a typical signature of noncommutativity and can be used in order to discriminate it against other new physics effects. We have found this dependence to be best suited for deriving the sensitivity bounds on the noncommutative scale Lambda_NC. By studying pp -> Z gamma -> l^+l^- gamma to first order in the noncommutative parameter Theta, we show in the first part of this work that measurements at the LHC are sensitive to noncommutative effects only in certain cases, giving bounds on the noncommutative scale of Lambda_NC > 1.2 TeV. Our result improved the bounds present in the literature coming from past and present collider experiments by one order of magnitude. In order to explore the whole parameter range of the noncommutativity, ILC studies are required. By means of e^+e^- -> Z gamma -> l^+l^- gamma to first order in Theta we have shown that ILC measurements are complementary to LHC measurements of the noncommutative parameters. In addition, the bounds on Lambda_NC derived from the ILC are significantly higher and reach Lambda_NC > 6 TeV. The second part of this work arose from the necessity to enlarge the range of validity of our model towards higher energies. Thus, we expand the neutral current sector of the noncommutative SM to second order in $\theta$. We found that, against the general expectation, the theory must be enlarged by additional parameters. The new parameters enter the theory as ambiguities of the Seiberg-Witten maps. The latter are not uniquely determined and differ by homogeneous solutions of the gauge equivalence equations. The expectation was that the ambiguities correspond to field redefinitions and therefore should vanish in scattering matrix elements. However, we proved that this is not the case, and the ambiguities do affect physical observables. Our conjecture is, that every order in Theta will introduce new parameters to the theory. However, only the experiment can decide to what extent efforts with still higher orders in Theta are reasonable and will also give directions for the development of theoretical models of noncommutative QFTs.
The continuously increase in resistance of human pathogenic microorganisms to the known antibiotics leads to the necessity for searching new sources for production of new active antimicrobial compounds from different natural sources especially plants, since many plants have been found to be able to produce antimicrobial compounds as a defense phenomenon against invading microorganisms. The aim of this work is to screen cultures for production of antimicrobial activity against representative of human pathogenic microorganisms and selection the most active cell culture producing antimicrobial protein(s) which are active against these pathogenic microorganisms and also isolation ,purification of the active protein(s) and cloning of its/their genes. Ten different plant suspension cultures have been screened in presence of nine elicitors for their antimicrobial activity against five selected human pathogenic microorganisms, and it has been found that the heterotrophic cultures are more active against the tester isolates than the autotrophic ones. The intracellular fraction of the mixotrophic Arabidopsis thaliana culture elicited with salicylic acid showed the highest antimicrobial activity against the tester isolates. The presence of proteinous antimicrobial activity has been elucidated by testing the activity of ammonium sulphate precipitate against Candida maltosa. High speed centrifugation technique has been used for partial purification of the active protein. The proteinous nature of the isolated compound has been confirmed by using bioautography technique and its molecular weight could be estimated to be around 26KDa. The active protein has been purified using gel filtration, and using mass spectrometry technique, for microsequencing of the active protein, it has been found that the function of the protein is unknown and we have termed it as AtPDP1 according to Arabidopsis thaliana Plat-Domain Protein1, since it contains a plant stress domain termed PLAT domain. It has been found that a second protein from the same plant with high homology level to AtPDP1 with the same domain, we termed it as AtPDP2. Genes for AtPDP1 and AtPDP2 have been cloned in E. coli using PGEM-T easy vector. The expression of both genes have been tested using Digital Northern program, and it has been observed that both genes are induced by different pathogens, chemicals known to induce defense in plant cells and also different hormones. We tried to clone the gene for AtPDP1 in PBI121 binary vector under the control of an elicitor inducible promoter of a proteinase inhibitor gene, to test its function in plant by overexpression, but we did not succeeded. Also the work aims to cloning the different known thaumatin genes from Arabidopsis thaliana for future work which represented by testing their expression under different stimuli, since most thaumatins have antimicrobial activity and some of them are active against Candida spp..Thirteen genes of known thaumatins from Arabidopsis thaliana have been cloned in PGEM-Teasy vector in DH5-alpha cells. coli cells. The expression of the thirteen genes has been done using Digital Northern program and it has been found that different genes show different expressions under different stimuli and the expression of At1g75800 gene was the maximum under all stimuli. The minimum expression of genes was for At1g75050. The rest of thaumatin genes showed moderate expressions under different stimuli.
In vorliegender Studie wurde an histologischen Präparaten mittels immunhistochemischen Färbungen der Übergangsbereich zwischen oraler Mukosa und transplantiertem Jejunumsegment untersucht. Mit der Fragestellung ob sich die Strukturen im Übergangsbereich zwischen freiem Jejunumtransplantat und oraler Mukosa funktionell verändern und ob die Dünndarmepithelien einer morphologischen Umwandlung unterliegen. Zu diesem Zweck wurden die Gewebeschnitte nach der LSABC Methode mit verschiedenen Antikörpern markiert die spezifisch das zu bestimmende Epithel anfärbten. Die Differentzierung der Epithelien erfolgte durch für jede Epithelart spezifische Zytokeratine. Nachgewiesen wurde eine Abflachung des Zottenreliefs sowie eine numerische Becherzellatrophie. In unseren histologisch nachuntersuchten Gewebeproben stellte sich die Grenze zwischen transplantiertem Jejunumsegment und mehrschichtigem Plattenepithel exakt und scharf begrenzt dar. Weder Zellcluster von mehrschichtigem Plattenepithel im Bereich des Dünndarms, noch eine Transformationszone, wie sie bei Zellmetaplasie vorkommt konnte nachgewiesen werden. Auch hielten die dünndarmeigenen Gefäße die Grenze zwischen den beiden Geweben strikt ein und verliefen ebenso scharf begrenzt. Subepithelial zeigte sich zwar zu Beginn eine entzündlich bedingte Gefäßproliferation mit schütterem leukozytären Infiltrat, welches aber im Laufe der Zeit durch kollagenfasereiches Bindegewebe narbig ersetzt wurde. Die nachweisbaren CD 4 positiven Entzündungszellen waren nicht über das gewöhnliche Ausmaß vermehrt, es kommt zur Ausbildung einer Gewebsgrenze die von beiden Epithelien respektiert wird unter der Vereinigung des subepithelialen Bindegewebes. Dies alles kann als Bestätigung dafür angesehen werden, dass die Rekonstruktion großer Defekte mittels freiem Jejunumtransplantat auch über einen Zeitraum von mehr als 21 Jahren erfolgreich ist und das Transplantat seinen Anforderungen in der neuen Umgebung standhält.
Mehrere Autoren haben schon die Intra- und Interobserver-Variabilität bei der Bestimmung des Schilddrüsenvolumens und knotiger Herdbefunde mit Hilfe des zweidimensionalen (2D) Ultraschalls evaluiert. Darüber hinaus wurde über Interobserver-Korrelationen für Schilddrüsenvolumenmessungen berichtet. Es gibt jedoch keine prospektive verblindete Studie, die die Intra- bzw. Interobserver-Variabilität bei der Volumenbestimmung der gesamten Schilddrüse an gesunden Probanden bzw. einzelner Knoten unterschiedlicher Echogenität an einem Phantom untersucht hat. Die Ergebnisse der Einzelstudien sollen hier vorgestellt und – soweit möglich – miteinander verglichen werden. Im Rahmen einer quantitativen Studie mit dem hier präsentierten Schilddrüsenphantom soll die Intra- und Interobserver-Variabilität bei der 2D-Ultraschallvolumetrie einzelner Knoten unterschiedlicher Größe und Echogenität und der Schilddrüsenlappen evaluiert werden. Da Schilddrüsenknoten wegen des geringeren Volumens und ihrer oft unscharfen Randkontur schwieriger zu entdecken und auszumessen sind als die Gesamtschilddrüse, soll untersucht werden, welche Größenordnungen des Messfehlers auftreten und in welcher Relation sie zueinander stehen. Außerdem soll der methodenimmanente Fehler quantifiziert und detektierbare Volumenänderungen erfassbar gemacht werden. Bisher war in der Schilddrüsensonographie kein geeignetes Phantom verfügbar, das kommerziell erhältlich ist und mit dem qualitativ unterschiedliche intrathyreoidale Herdbefunde untersucht werden können. Die vorliegende Studie an gesunden Probanden hatte das primäre Ziel, die Frage nach der Quantifizierbarkeit von Unsicherheitsfaktoren in der Schilddrüsenvolumetrie durch den konventionellen 2D-Ultraschall im Vergleich zu 3D-Referenzvolumina bei gesunden Erwachsenen möglichst exakt zu beantworten und die Untersucherabhängigkeit der Methode zu demonstrieren. Damit soll die Genauigkeit (Richtigkeit und Präzision) der sonographischen Schilddrüsendiagnostik mathematisch erfasst und eine bessere Bewertungsgrundlage für die Frage nach der Reproduzierbarkeit von Ultraschall-Volumenbestimmungen der Schilddrüse und ihrer pathologischen Veränderungen geschaffen werden. Hierfür wurden möglichst aussagekräftige statistische Parameter wie die Intra- und Interobserver-Variabilität, der systematische und zufällige Fehler, der reine Fehler der Messmethode, minimale, sicher detektierbare Volumenänderungen und im Rahmen einer multivariaten Reliabilitätsanalyse die Reliabilitätskoeffizienten untersucht. Ein weiteres Ziel dieser Studie bestand darin, die Reliabilität der in der klinischen Routine benutzten Ellipsoidformel zur Berechnung des Schilddrüsenvolumens zu überprüfen.
Infrared photodissociation spectroscopy of ionic hydrocarbons : microsolvation and protonation sites
(2007)
This work has presented a spectroscopic analysis of three types of hydrocarbon cations: two ionized aromatic hydrocarbons, two protonated aromatic hydrocarbons and the cation of a fundamental radical hydrocarbon. The experiments were centered on the proton stretch vibrations of mass-selected complexes of these systems and polar (H2O) and non polar (Ar, N2, CO2) ligands. The experiments have been done in a tandem mass spectrometer coupled with an electron impact ionization ion source; an OPO laser system was used as tunable IR light source. All the proposed dimer structures have been also modeled using quantum chemical calculations (QCC). These calculations have consistently been matched with the experimental results and have enabled clear identification of the spectral features observed. This has enabled the evaluation of thermochemical properties which could not be extracted directly from experiment. The experiments done on complexes of 1-Np+ and Im+ have allowed for the acidity of their various groups to be probed: the shifts in the frequency as well as the enhancement in the intensity of the OH and NH stretch vibrations resulting from the complexation have yielded dependences on both the species (L) and the number (n) of the ligands. OH bound 1-Np+···Ar has been detected for the first time, showing that the REMPI-IRPD method is severely limited with respect to the production of the most stable isomer of a given cationic complex. The detection of c-1-Np+···(N2)n corresponds to the first observation of c-1-Np+ complexes and enables thus direct comparison of both 1-Np+ rotamers. The shift of the NH vibration of Im+···N2(H) yielded the first experimental estimate for the PA of the imidazyl radical. It was also found that the most stable 1-Np+···Ar and Im+···Ar structures differ qualitatively from that of the corresponding neutral dimers (H-bound vs pi-bound), emphasizing the large impact of ionization on the interaction potential and the preferred recognition motif between acidic aromatic molecules (A) and nonpolar ligands. The IRPD spectra of 1-Np+···Ln and Im+···Ln yielded spectroscopic information about the CH, NH and OH stretch vibrations of bare 1-Np+ and Im+. The dependence of the shifts in the frequency of the OH and NH stretch vibrations allows for creating microsolvation models. The spectroscopic results obtained on size-selected 1-NpH+···Ln show that, in the output of the presently used ion source, three classes of 1-NpH+ isomers can be identified: oxonium ions (1-Np protonated at the O atom); carbenium ions obtained by protonation in the para and ortho positions with respect to the OH functional group; carbenium ions obtained by the addition of a proton to well-defined sites on the second naphthalene ring. The spectral identification of these three classes of protonation sites is supported by their different photofragmentation patterns. It was demonstrated that the spectroscopic monitoring of the microsolvation of ImH+ in Ar and N2 together with the QCCs paint a very detailed picture of the microsolvation process, evidencing clear differences between the microsolvation models as function of the PA of the ligands. Important differences have also been identified between the various binding sites, enabling the creation of a clear scale of priorities for occupation of the binding sites during microsolvation. The application of IRPD to the study of microhydrated ImH+ provided for the first time direct spectroscopic information on the properties of the N-H bonds of this biomolecular building block under controlled microhydration. It was demonstrated that, as protonation enhances the acidity of the NH groups, the ability for proton conductivity of ImH+ increases. A very important result is derived from the IRPD spectroscopy of C2H5+···L (L = Ar, N2, CO2, CH4) dimers. The equilibrium geometry of the C2H5+ has long been debated. Now, IRPD spectra were recorded over the range of the CH stretch fundamentals (covering possible sp3 and sp2 hybridization of C). Depending on the ligand species, the spectra are found to be dominated by the fingerprint of two largely different dimer geometries. Using the experimental C2H5+···Ar spectrum and the corresponding QCCs, the structure of the (weakly perturbed) C2H5+ was found to be the nonclassical one, with one proton straddling across the C=C bond of the H2C=CH2. On the other hand, ligands like N2 and CH4 are strongly influencing the geometry, as seen in the spectral signatures of the C2H5+···N2 and C2H5+···CH4, which correspond to the classical [H2CCH3]+. It was thus demonstrated that while the nonclassical C2H5+ is the global minimum on the PES of the free [C2,H5]+, the structure of the C2H5+ can be strongly influenced by the chemical properties of the environment.