44 research outputs found
A felnőttkori figyelemhiányos hiperaktivitás zavar (ADHD) hibázáshoz kötött viselkedéses-és EEG kiváltott válasz eltérésének vizsgálata
A felnőttkori policisztás ovárium szindróma klinikai megjelenései, differenciáldiagnózisa és krónikus szövődményei
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Lu-177-labeled zirconia particles for radiation synovectomy
The present article describes the preparation of beta emitter lutetium-177-lebeled zirconia colloid and its preliminary physico-chemical and biological evaluation of suitability for local radionuclide therapy.
The new 177Lu-labeled therapeutic radiopharmaceutical candidate was based on the synthesis mode of a previously described zirconia nanoparticle system. Morphology and size of developed radiopharmaceutical compound were evaluated through scanning electron microscope and dynamic light scattering methods. The radiocolloid had a 1.7 micrometer mean diameter and showed suitable radiolabeling and colloid size in vitro stability at RT and during blood sera stability test. After the in vitro characterizations, the product was investigated in the course of the treatment of a spontaneously diseased dog veterinary patient’s hock joint completed with SPECT imaging follow-up measurements and a dual-isotope SPECT imaging tests with conventional 99mTc-MDP bone scintigraphy. In the treated dog any clinical side effects or signs of histopatological alterations of the joints could not be observed during the treatment. SPECT follow-up studies unequivocally showed appropriately high localization of the 177Lu-labeled colloid in hock joint and detectable but negligible radiocolloid leakages in the nearest lymph node, respectively
Inherently fluorescent and porous zirconia colloids : preparation, characterization and drug adsorption studies
Porous, fluorescent zirconia particles of nearly 380 nm diameter were prepared without template molecules
or labeling dyes. The porous structure is the result of aggregation-induced particle formation. The inherent
fluorescence is assigned to coordinatively unsaturated Zr4+ ions at the sol–gel derived ZrO2 surface. After
physico-chemical characterization of the native zirconia particles carboxyl and/or amine bearing drug molecules
(D,L-a-difluoromethylornithine – DFMO, ursolic acid – UA and doxorubicin – DOX) were adsorbed
onto their surface, and the products were analyzed with Fourier-transform infrared spectroscopy (FTIR),
thermogravimetry (TG), small-angle X-ray scattering (SAXS), fluorimetry and zeta potential vs. pH measurements.
We have found that DOX complexes coordinatively unsaturated Zr4+ ions without dislocating them,
while carboxyl-bearing drugs interact with basic surface Zr–OH sites eliminating some of the carbonate
species. The adsorption of UA at the zirconia surface shifts considerably the isoelectric point of the surface
and thus provides kinetic stability to the particles at physiological pH. An in vivo biodistribution study in
two healthy dogs performed by SPECT/CT detection after 99mTc labeling of the nanocarriers has shown
the possibility of drug delivery application