Ultrastructure of Rat Kidneys after Intravenous Administration of Modified Magnetite Nanoparticles

Abstract

The ultrastructure of nephrocytes of the proximal and distal convoluted tubules, podocytes, mesangial cells, and macrophages of the interstitial connective tissue was studied after single intravenous administration of magnetite nanoparticles modified with chitosan (magnetic nanospheres) or lipids (magnetic liposomes). Transmission electron microscopy showed ultrastructural features of absorption of magnetite nanoparticles. The shape, size, and number of vesicles containing nanoparticles in nephrocytes of convoluted tubules and macrophages after administration of the suspensions of magnetic nanospheres and magnetic liposomes were described.

Magnetic Hyperthermia and Radiation Therapy: Radiobiological Principles and Current Practice †

“…In addition, MNPs enjoy advantages due to their small size and chemistry: Unlike macro or microscopic ferromagnetic implants, MNPs can be introduced in the tumor without surgery, which is feasible only for large and accessible tumors. In fact, one possible route of administration is by injection into the bloodstream [ 165 , 212 , 213 , 214 , 215 ]. Since MNPs can be transported through the bloodstream, they may be used to treat small and surgically not addressable tumors, such as diffuse tumors and metastases.…”

“…Unlike macro or microscopic ferromagnetic implants, MNPs can be introduced in the tumor without surgery, which is feasible only for large and accessible tumors. In fact, one possible route of administration is by injection into the bloodstream [ 165 , 212 , 213 , 214 , 215 ].…”

Recommendations for In Vitro and In Vivo Testing of Magnetic Nanoparticle Hyperthermia Combined with Radiation Therapy

“…Magnetic Hyperthermia (MH) is a cutting edge technology, still in its infancy, that is based on the principle of embedding a heating source, namely magnetic nanoparticles (MNPs), into the targeted tissue/tumor and heating it by using an external alternating magnetic field [ 41 ]. Its attractiveness lies in the fact that: (a) the MNPs can, in principle, reach deep-seated tumors via the bloodstream [ 42 , 43 ]; (b) the location of the MNPs can be determined using various imaging techniques [ 44 , 45 , 46 ]; (c) the MNPs can also act as temperature probes, providing detailed 3D information about the temperature distribution in the tumor [ 47 , 48 ]; (d) the MNPs can be functionalized with specific ligands in order to improve targeting [ 45 , 49 , 50 ]; (e) the MNPs can be conjugated with chemotherapeutic drugs to increase the efficacy of magnetic hyperthermia [ 51 ]; (f) the technique is minimally invasive, requiring only a simple injection; and (g) the procedure is rather comfortable since the patient is not required to wear special suits or be immersed in a thermal bath [ 52 ].…”