1550 ASSESSMENT OF TOXICITY OF STONE-MAGNETIZING MICROPARTICLES IN A MURINE MODEL

Abstract

You have accessJournal of UrologyStone Disease: New Technology/SWL, Ureteroscopic or Percutaneous Stone Removal1 Apr 20111550 ASSESSMENT OF TOXICITY OF STONE-MAGNETIZING MICROPARTICLES IN A MURINE MODEL Sara Best, Wareef Kabbani, Saad Mir, Chester Donnally, Stacey McLeroy, Ephrem Olweny, Bruce Gnade, Margaret Pearle, and Jeffrey Cadeddu Sara BestSara Best Dallas, TX More articles by this author , Wareef KabbaniWareef Kabbani Dallas, TX More articles by this author , Saad MirSaad Mir Dallas, TX More articles by this author , Chester DonnallyChester Donnally Dallas, TX More articles by this author , Stacey McLeroyStacey McLeroy Dallas, TX More articles by this author , Ephrem OlwenyEphrem Olweny Dallas, TX More articles by this author , Bruce GnadeBruce Gnade Richardson, TX More articles by this author , Margaret PearleMargaret Pearle Dallas, TX More articles by this author , and Jeffrey CadedduJeffrey Cadeddu Dallas, TX More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.1558AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We have developed novel iron-based microparticles (Fe-MP) that render calcium oxalate stone fragments paramagnetic, allowing them to be manipulated using magnetic instrumentation. Our ultimate goal is to use magnetic tools and a solution of these particles as the irrigation fluid during ureteroscopy to facilitate fragment retrieval. Exposure of stone fragments to a solution of Fe-MP has been shown to improve the efficiency of stone extraction in an inanimate model. In this investigation we assessed the effects of venous and bladder instillation of Fe-MP in a murine model. METHODS 42 six week old mice were used in the study. 21 mice were given a 100 μL tail vein injection of either saline or 0.5, 1, or 5 mg/ml concentration of Fe-MP. Another 21 mice received a 150 μL, 30 min bladder instillation of the same. The mice were then weighed daily and their overall health status was assessed. Mice were sacrificed at 1, 3, or 28 days after Fe-MP exposure and the lungs, liver, spleen, brain, bladder, and kidneys were examined microscopically with H&E staining for the presence of Fe-MP and any associated tissue effects. RESULTS All mice survived until the assigned endpoint, gained weight appropriately, and appeared healthy after exposure to Fe-MP. H&E stain of the organs in the bladder instillation group showed no presence of the Fe-MP in the tissues and no differences between the control and those receiving Fe-MP. In the mice receiving an IV bolus of Fe-MP, the microparticles were visible in the liver, lungs, and spleen tissues by 28 days in a dose-dependent fashion. There was also evidence of dose-dependent mild to moderate liver inflammation, though mild inflammation was noted even in the saline control animals in both groups. Mild lung inflammation was also seen in 4/6 of the Fe-MP IV injection animals at 28 days. No microparticles or inflammation were seen in the bladder, brain, or kidney tissue in any of the animals. CONCLUSIONS Since the Fe-MP solution is intended to be used as an irrigation solution at a concentration of 1mg/ml during ureteroscopy, the absence of findings in the cohort undergoing bladder instillation/urothelial exposure to Fe-MP is promising. Due to the potential risk of bloodstream exposure to Fe-MP if the urothelium is traumatized, further investigation of the implications of the findings in the IV bolus group should be undertaken. However, the response seems dose-related and inadvertent exposure is likely to be at a much lower concentration than those tested. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e622-e623 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sara Best Dallas, TX More articles by this author Wareef Kabbani Dallas, TX More articles by this author Saad Mir Dallas, TX More articles by this author Chester Donnally Dallas, TX More articles by this author Stacey McLeroy Dallas, TX More articles by this author Ephrem Olweny Dallas, TX More articles by this author Bruce Gnade Richardson, TX More articles by this author Margaret Pearle Dallas, TX More articles by this author Jeffrey Cadeddu Dallas, TX More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...