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161	Development and Validation of Analytical Models for Diffuse Fluorescence Spectroscopy/Imaging in Regular Geometries Ayyalasomayajula, Kalyan Ram January 2013 (has links) (PDF) New advances in computational modeling and instrumentation in the past decade has enabled the use of electromagnetic radiation for non-invasive monitoring of the physio-logical state of biological tissues. The near infrared (NIR) light having the wavelength range of 600 nm -1000 nm has been the main contender in these emerging molecular imaging modalities. Assessment of accurate pathological condition of the tissue under investigation relies on the contrast in the molecular images, where the endogenous contrast may not be suﬃcient in these scenarios. The ﬂuorescence (exogenous) contrast agents have been deployed to overcome these diﬃculties, where the preferential uptake by the tumor vasculature leads to high contrast,making this modality one of the biggest contenders in small-animal and soft-tissue molecular imaging modalities. In Fluorescence diﬀuse optical spectroscopy/imaging, this exogenous drug is excited by NIR laser light causing the emission of the ﬂuorescence light. The emitted ﬂuorescence light is typically dependent on the life time and concentration of the exogenous drug coupled with physiology associated with the tissue under investigation. As there is an excitation and emission of the light,the underlying physics of the problem is described by a coupled diﬀusion equations. These coupled diﬀusion equations are typically solved by advanced numerical methods, which tend to be computationally demanding. In this work, analytical solutions for these coupled partial diﬀerential equations (PDEs) for the regular geometries for both time-domain and frequency-domain cases were developed. Till now, the existing literature has not dealt with all regular geometries and derived analytical solutions were only for couple of geometries. Here a universally acceptable generic solution was developed based on Green’s function approach that is applicable to any regular geometry. Using this, the analytical solutions for the regular geometries that is encountered in diﬀuse ﬂuorescence spectroscopy/imaging were obtained. These solutions can play an important role in determining the bulk ﬂuorescence properties of the tissue, which could act as good initial guesses for the advanced image reconstruction techniques and/or can also facilitate the calibration of experimental ﬂuorescence data by removing biases and source-detector variations. In the second part of this work, the developed analytical models for regular geometries were validated through comparison with the established numerical models that are traditionally used in the diﬀuse ﬂuorescence spectroscopy/imaging. This comparison not only validated the developed analytical models, but also showed that analytical models are capable of providing bulk ﬂuorescence properties with at least one order of magnitude less computational cost compared to the highly optimized traditional numerical models. Medical Optics Medical Imaging Diffuse Fluorescence Spectroscopy Fluorescence Diffuse Optical Imaging Molecular Imaging Fouorescence Spectroscopy/Imaging Fluorescence Optical Breast Imaging Flrorescence Optical Brain Imaging Fluorescence Diffuse Optical Imaging FDOI Biotechnology
162	Synthese molekularer Bildgebungssonden für die molekulare Magnetresonanztomographie / Funktionalisierung von superparamagnetischen Eisenoxidnanopartikeln Figge, Lena 01 July 2014 (has links) Zweck der molekularen Bildgebung ist es, biologische Prozesse auf zellulärer und molekularer Ebene zu messen und zu charakterisieren, um so die Ursachen von Krankheiten und Veränderungen im Organismus zu diagnostizieren. Sie basiert auf dem Einsatz molekularer Bildgebungssonden, welche einen spezifischen biologischen Vorgang darstellen oder sich spezifisch in dem zu untersuchenden Gewebe anreichern oder aktiviert werden. Ziel dieser Arbeit war die Entwicklung und Analyse neuer Bildgebungssonden für die spezifische in-vivo-Bildgebung der Apoptose und von Enzymaktivitäten mittels Magnetresonanztomographie (MRT) auf der Grundlage sehr kleiner Eisenoxidnanopartikel (very small iron oxide particles, VSOP). VSOP sind superparamagnetisch und durch ihre negativ geladene Citrathülle elektrostatisch stabilisiert. Für die Apoptose-Bildgebung sollte durch Bindung des Proteins Annexin A5 (AnxA5) an die Citrathülle der VSOP eine zielgerichtete Sonde hergestellt werden (AnxA5-VSOP). Für die Bildgebung von Enzymaktivitäten sollte eine durch die Matrixmetalloproteinase-9 (MMP-9) aktivierbare Sonde hergestellt werden (Protease-spezifische Eisenoxidpartikel, PSOP). / The goal of molecular imaging is to characterize and measure biological processes at cellular and molecular levels for the purpose of diagnosing the cause of diseases and molecular abnormalities. Molecular imaging is based on the use of probes with a high affinity to the target tissue and / or which are specifically activated. The aim of this study was to develop and analyze new molecular imaging probes for the in vivo imaging of apoptosis and enzyme activity using magnetic resonance imaging (MRI), based on very small iron oxide particles (VSOP). VSOP are superparamagnetic and electrostatically stabilized due to their negatively charged citrate surface. For the imaging of apoptosis the protein annexin A5 (AnxA5) was coupled to the citrate surface (AnxA5-VSOP). For the imaging of enzyme activities an activatable imaging probe with a cleavage site for the matrix metalloproteinase 9 (MMP-9) was synthesized (protease-specific iron oxide particles, PSOP). Magnetresonanztomographie Apoptose Enzymaktivitäten molekulare Bildgebungssonde superparamagnetisch VSOP Annexin A5 PSOP Matrixmetalloproteinase magnetic resonance imaging apoptosis enzyme activity molecular imaging probe superparamagnetic very small iron oxide particles VSOP Annexin A5 protease-specific iron oxide particles PSOP matrix metalloproteinase 30 Chemie YR 2404 YR 2520 ddc:540
163	Évaluation de l'innocuité et de l'efficacité d'un dérivé synthétique marqué de l'adrénomédulline dans l'imagerie moléculaire pulmonaire chez l'humain Levac, Xavier 08 1900 (has links) No description available. Phase I Adrénomédulline Médecine nucléaire Technétium Peptide Radiotraceur Imagerie moléculaire Étude clinique SPECT Hypertension artérielle pulmonaire Circulation pulmonaire Physiologie circulatoire Innocuité Sécurité Endothélium Marqueur moléculaire Physique nucléaire Imagerie diagnostique RAMP Receptor activity modifying protein Endothélium pulmonaire Hypertension pulmonaire HTAP Calcitonin receptor-like receptor Dosimétrie Adrenomedullin Nuclear medicine Radiotracer Molecular imaging Clinical study Pulmonary arterial hypertension Pulmonary circulation Safety Molecular marker Nuclear physics Diagnostic imaging Pulmonary endothelium Pulmonary hypertension PAH Dosimetry

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