scholarly journals In Vivo 3T Magnetic Resonance Imaging Using a Biologically Specific Contrast Agent for Prostate Cancer: A Nude Mouse Model

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Christopher Brian Abraham ◽  
Prashant Jani ◽  
Roxanne Turuba ◽  
Michael Campbell ◽  
Ingeborg Zehbe ◽  
...  

We characterized in vivo a functional superparamagnetic iron-oxide magnetic resonance contrast agent that shortens the T2 relaxation time in magnetic resonance imaging (MRI) of prostate cancer xenografts. The agent was developed by conjugating Molday ION™ carboxyl-6 (MIC6), with a deimmunized mouse monoclonal antibody (muJ591) targeting prostate-specific membrane antigen (PSMA). This functional contrast agent could be used as a noninvasive method to detect prostate cancer cells that are PSMA positive and more readily differentiate them from surrounding tissues for treatment. The functional contrast agent was injected intravenously into mice and its effect was compared to both MIC6 (without conjugated antibody) and phosphate-buffered saline (PBS) injection controls. MR imaging was performed on a clinical 3T MRI scanner using a multiecho spin echo (MESE) sequence to obtain T2 relaxation time values. Inductively coupled plasma atomic emission spectroscopy was used to confirm an increase in elemental iron in injected mice tumours relative to controls. Histological examination of H&E stained tissues showed normal morphology of the tissues collected.

2021 ◽  
Vol 20 ◽  
pp. 153303382110365
Author(s):  
Lin Qiu ◽  
Shuwen Zhou ◽  
Ying Li ◽  
Wen Rui ◽  
Pengfei Cui ◽  
...  

Bifunctional magnetic/fluorescent core-shell silica nanospheres (MNPs) encapsulated with the magnetic Fe3O4 core and a derivate of 8-amimoquinoline (N-(quinolin-8-yl)-2-(3-(triethoxysilyl) propylamino) acetamide) (QTEPA) into the shell were synthesized. These functional MNPs were prepared with a modified stöber method and the formed Fe3O4@SiO2-QTEPA core-shell nanocomposites are biocompatible, water-dispersible, and stable. These prepared nanoparticles were characterized by X-ray power diffraction (XRD), transmission electron microscopy (TEM), thermoelectric plasma Quad II inductively coupled plasma mass spectrometry (ICP-MS), superconducting quantum interference device (SQUID), TG/DTA thermal analyzer (TGA) and Fourier transform infrared spectroscopy (FTIR). Further application of the nanoparticles in detecting Zn2+ was confirmed by the fluorescence experiment: the nanosensor shows high selectivity and sensitivity to Zn2+ with a 22-fold fluorescence emission enhancement in the presence of 10 μM Zn2+. Moreover, the transverse relaxivity measurements show that the core-shell MNPs have T2 relaxivity (r2) of 155.05 mM−1 S−1 based on Fe concentration on the 3.0 T scanner, suggesting that the compound can be used as a negative contrast agent for MRI. Further in vivo experiments showed that these MNPs could be used as MRI contrast agent. Therefore, the new nanosensor provides the dual modality of magnetic resonance imaging and optical imaging.


F1000Research ◽  
2014 ◽  
Vol 2 ◽  
pp. 252
Author(s):  
Rachael A Panizzo ◽  
David G Gadian ◽  
Jane C Sowden ◽  
Jack A Wells ◽  
Mark F Lythgoe ◽  
...  

Efficacy of neural stem/progenitor cell (NPC) therapies after cerebral ischaemia could be better evaluated by monitoring in vivo migration and distribution of cells post-engraftment in parallel with analysis of lesion volume and functional recovery. Magnetic resonance imaging (MRI) is ideally placed to achieve this, but still poses several challenges. We show that combining the ferumoxide MRI contrast agent Endorem with protamine sulphate (FePro) improves iron oxide uptake in cells compared to Endorem alone and is non-toxic. Hence FePro complex is a better contrast agent than Endorem for monitoring NPCs. FePro complex-labelled NPCs proliferated and differentiated normally in vitro, and upon grafting into the brain 48 hours post-ischaemia they were detected in vivo by MRI. Imaging over four weeks showed the development of a confounding endogenous hypointense contrast evolution at later timepoints within the lesioned tissue. This was at least partly due to accumulation within the lesion of macrophages and endogenous iron. Neither significant NPC migration, assessed by MRI and histologically, nor a reduction in the ischaemic lesion volume was observed in NPC-grafted brains.  Crucially, while MRI provides reliable information on engrafted cell location early after an ischaemic insult, pathophysiological changes to ischaemic lesions can interfere with cellular imaging at later timepoints.


1992 ◽  
Vol 101 (3) ◽  
pp. 248-254 ◽  
Author(s):  
Kenny H. Chan ◽  
William J. Doyle ◽  
J. Douglas Swarts ◽  
David Kardatzke ◽  
Yoshie Hashida ◽  
...  

The use of magnetic resonance imaging in otitis media research is being explored in our laboratory. In this study, we present a new method for studying changes in the middle ear cleft due to an episode of induced otitis media in the chinchilla model. It uses gadolinium-diethylenetriamine pentaacetic acid, a magnetic resonance imaging contrast agent, to examine the uptake and washout characteristics of middle ear mucosa during an inflammatory episode. Parameters such as the time to maximum intensity of the mucosa and the washout rate of the contrast agent from the mucosa were significantly correlated to the duration of the infection.


Circulation ◽  
2005 ◽  
Vol 112 (11) ◽  
pp. 1594-1600 ◽  
Author(s):  
Marc Sirol ◽  
Valentin Fuster ◽  
Juan J. Badimon ◽  
John T. Fallon ◽  
Jean-François Toussaint ◽  
...  

2017 ◽  
Vol 8 (6) ◽  
pp. 1104-1113 ◽  
Author(s):  
Yi Cao ◽  
Min Liu ◽  
Guangyue Zu ◽  
Ye Kuang ◽  
Xiaoyan Tong ◽  
...  

To explore a convenient and efficient strategy for constructing tumor-targeted T1 mCAs for MRI, hyperbranched poly(glycerol) prepared in one-pot was used to conjugate gadolinium chelates and folic acid ligands through “click chemistry”.


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