Radiology presentations (MU)
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Items in this collection are public presentations made by Department of Radiology faculty, staff, and students, either alone or as co-authors, and which may or may not have been published in an alternate format. Items may contain more than one file type.
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Item A Comparative Study between Antibody and Peptide Conjugated Gold Nanoparticles for In Vivo Targeting of EGFR in Pancreatic Cancer Bearing Mice Models [abstract](2010-03) Zambre, Ajit; Shukla, Ravi; Chanda, Nripen; Mukharjee, Priyabrata; Mukhopadhyay, Debabrata; Boote, Evan; Kannan, Raghuraman; Katti, Kattesh V.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Pancreatic cancer is the fourth leading cause of cancer related deaths in the United States due to its severe aggressiveness and lethal malignancy. Epidermal Growth Factor Receptor (EGFR) is over expressed in more than 95% of human pancreatic cancer patients. A number of peptides and monoclonal antibodies have been developed to target the EGFR in pancreatic cancer. Our research has focused on developing EGFR targeting biomolecule conjugated gold nanoparticles for the diagnosis and staging of various cancers. In this study, we synthesized a series of Antibody EGFR and EGFR-peptide conjugated AuNPs. We investigated the in vivo EGFR targeting characteristics of these conjugates in pancreatic tumor bearing SCID mice models. Our investigation establishes that the peptide conjugated AuNPs have high in vivo mobility and targets pancreatic tumor effectively. We have also established that EGFR-peptide -AuNP conjugates act as better X-ray contrast agents for early detection of pancreatic cancer in mice models. The details of this comparative study will be presented in this poster.Item Development of Absorption and Fluorescence Probes Based on Mouse Model for Molecular Optical Imaging [abstract](2010) Ma, Lixin; Yu, Ping, Ph. D.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)In this work we summarize our collaborative research on a project to develop absorption and fluorescence targeting probes. Several groups from University of Missouri and Harry S. Truman Memorial Veteran's Hospital including Dr. Ma's group, Dr. Yu's group, Dr. Smith's group, Dr. Hoffman's group, and Professor Wynn Volkert have been involved in the project. Our goal is to develop probes based on mouse model for molecular optical imaging. In vivo imaging of targeted fluorescence molecular probes, or molecular imaging, is an emerging field in biomedical imaging. During the past forty years, three dimensional biomedical imaging technologies such as CT and MRI have been extensively used in human health and diseases. However, the human body is a complex and interactive biological system. A fundamental scientific barrier in previous biomedical imaging technologies is their limited ability to study physiological processes in vivo at the cellular and molecular levels. Molecular imaging technologies can overcome this barrier. Optical imaging modalities have the highest sensitivity compared to other imaging techniques. So they are good candidates for molecular imaging. We develop probes for two biomedical optical imaging techniques. The first technique is coherence domain imaging. This technique can be used to monitor interactions between targeted peptide conjugates and cancer cells at a tissue level. It requires absorption properties of the probe for effective molecular imaging. The second technique is fluorescence mediated tomographic imaging using an image-intensified CCD camera. This technique uses fluorescence of the probe for molecular imaging. Dye bombesin conjugates are synthesized for site-specific absorption and fluorescence imaging in human prostate and breast cancer cells. Bombesin (BBN), an amphibian analog to the endogenous ligand, binds to the gastrin releasing peptide receptors (GRPr) with high specificity and affinity. BBN conjugates have a specific significance in cancer detection and therapy due to high over-expression levels of GRPrs in human cancer cells. Previously, we have developed an Alexa Fluor 680 BBN peptide conjugate. This probe can not be used as an absorption probe in near-infrared imaging since its absorption peak is in the visible wavelength range. In addition, long wavelength fluorescence is desired because long wavelength photons can penetrate deeper into tissue when using the conjugates as a fluorescent probe. The new absorption and fluorescent probe we developed is based on the last eight-residues of BBN and labeled with Alexa Fluor 750 through an effective linker. The developed probe, AF750-BetaAla-BBN[7-14]NH2, exhibits optimal pharmacokinetic properties for targeting GRPr over-expressing cancer cells in mice. Absorption spectra have been measured and showed absorption peaks at 690nm, 720nm and 735nm. Fluorescent band is located at 755nm. Fluorescent microscopic imaging of the conjugates in human PC-3 prostate cancer and T-47D breast cancer cells indicated specific uptake and internalization in vitro. In vivo optical and MR imaging was performed in SCID mice bearing human breast and prostate xenografts. In vitro and in vivo studies have demonstrated the effectiveness of the fluorescent probe Alexa Fluor 750-BetaAla-BBN[7-14]NH2 to specifically target GRPr overexpressed cancer tissues.Item Early Breast Cancer Detection Using Fluorescence Mediated Tomographic Imaging [abstract](2010) Yu, Ping, Ph. D.; Ma, Lixin; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Development of reliable technologies for early detection and screening of breast cancer is significant since the overall accuracy of traditional mammography remains low for diagnosis of benign and malignant lesions. In vivo imaging of targeted molecular probes, or molecular imaging, is an emerging field for early detection of cancer. Nuclear molecular imaging modalities such as positron-emission tomography (PET) and single-photon-emission computed tomography (SPECT) have been used for obtaining functional information of cancerous tissue. However, these technologies are limited with low resolution for detection of subcentimetric tumor deposits and lack of an anatomical reference frame to accurately locate molecular events. On the other hand, MRI has high spatial resolution but relatively low sensitivity to targeting probes. Although several multimodality imaging technologies are being developed, the systems are highly incomplete and expensive. Optical imaging is particularly well suited for molecular imaging, as fluorescent probes are sensitive and can be specifically conjugated to small molecules, antibodies and proteins. Optical imaging has the advantages of being non-invasive, non-ionizing, and having high sensitivity for optical-labeled probe, relatively low cost and rapid imaging time. The primary objective of this project is to develop a three-dimensional fluorescence mediated tomography (FMT) system based on a frequency domain heterodyne technique that uses an image-intensified CCD camera. The proposed technique provides the highest resolution and sensitivity and faster acquisition rates in the measurement of the phase and amplitude for frequency domain diffuse photons. The fluorescence tomography system will be used within PET and MRI scanners for dual imaging of molecular targets of cancer cells. The proposed research will develop/refine a combined FMT/PET/MRI technology utilizing FMT as a bridge to integrate PET and MRI and form a multimodal imaging platform. The developed frequency domain heterodyne imaging system will gain a factor of 10 in sensitivity via reducing phase-amplitude cross-talk compared to a homodyne system using ICCD. The proposed multimodality imaging system FMT/PET will improve spatial resolution with a factor of 4. The technology developed in this proposal can be used in the development of tumor targeting pharmaceuticals for cancer diagnosis and therapy.Item A Novel Method to Monitor Sequential Displacement of Capped Ligands in Gold Nanoparticles [abstract](2010-02) Kulkarni, Rajesh R.; Chanda, Nripen; Shukla, Ravi; Nune, Satish K.; Katti, Kavita K.; Kannan, Raghuraman; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Nanochemistry of ligand displacement reactions has attracted much attention in recent years for the development of myriad of new gold nanomaterials. Gold nanoparticles have shown applications ranging from tumor imaging agent in nanomedicine to single electron devices in information technology. New gold materials are synthesized by exchange of neutral or anionic ligands with thiolated molecules. Completion of ligand substitution reactions in gold nanoparticles are monitored by using UV-Vis spectrometry. However, there are no methods available to monitor the sequence of the ligand substitution reactions. Monitoring and predicting the sequence of ligand substitutions would provide a convenient handle for the design and development of hybrid nanomaterials containing two or more ligands. In this context, we have developed a novel technique utilizing disc centrifuge systems to monitor the sequential displacement of ligands in various gold nanoconstructs. In our studies, we have used gold nanoparticles stabilized with both anionic and neutral ligands. Gold nanoparticles of various different substitutions have been identified and characterized by disc centrifuge systems. Details of substitution reactions and mechanism on monitoring the sequential displacement using strong ligands will be presented.Item Photoacoustic Detection of Circulating Prostate, Breast and Pancreatic Cancer cells using targeted Gold Nanoparticles: Implications of Green Nanotechnology in Molecular Imaging(2010-02) Shukla, Ravi; Gupta, Sagar Kishore, 1984-; Chanda, Nripen; Zambre, Ajit; Viator, John A.; Mukharjee, Priyabrata; Mukhopadhyay, Debabrata; Kannan, Raghuraman; Katti, Kattesh V.; University of Missouri (System); Missouri Life Sciences Summit (2010: University of Missouri--Kansas City)Circulating tumor cells are hallmarks of metastasis cancer. The presence of circulating tumor cells in blood stream correlates with the severity of disease. Photoacoustic imaging (PA) of tumor cells is an attractive technique for potential applications in diagnostic imaging of circulating tumor cells. However, the sensitivity of photoacoustic imaging of tumor cells depends on their photon absorption characteristics. In this context, gold nanoparticle embedded tumor cells offer significant advantages for diagnostic PA of single cells. As the PA absorptivity is directly proportional to the number of nanoparticles embedded within tumor cells, the propensity of nanoparticles to internalize within tumor cells will dictate the sensitivity for single cell detection. We are developing biocompatible gold nanoparticles to use them as probes as part of our ongoing effort toward the application of X ray CT Imaging, Ultra Sound (US) and photoacoustic imaging of circulating breast, pancreatic and prostate tumor cells. We, herein report our latest results which have shown that epigallocatechin gallate (EGCG)-conjugated gold nanoparticles (EGCG-AuNPs) internalize selectively within cancer cells providing threshold concentrations required for photo acoustic signals. In this presentation, we will describe, our recent results on the synthesis and characterization of EGCG gold nanoparticles, their cellular internalization and photo acoustic imaging of PC-3 prostate cancer cells and PANC-1 pancreatic cancer cells.