Human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles and administered intraperitoneally in a dose of 0.05 mg/kg exhibited a neuroprotective effect in experimental intracerebral posttraumatic hematomas (hemorrhagic stroke) and reduced animal mortality. Human recombinant erythropoietin, native and adsorbed on lactic and glycolic acid copolymer-based nanoparticles, exhibited no antistroke effect on this model. Analysis of reverse transcription PCR products showed that human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles more than 2-fold increased the expression of BDNF and NGF neurotrophins in the rat brain frontal cortex and hippocampus.
The research on the nansomal forms s of low-sialylated recombinant human erythropoietin (ls-rhEPO) gave evidence for the efficiency of the nanotechnological approach to targeted delivery of this protein to the brain of experimental animals. Nanosomal ls-rhEPO formulations were found to exhibit neuroprotector activity. The established ability of the nanosomal formulations of ls-rhEPO to enhance BDNF and NGF gene expression in animal brain is to a great extent responsible for the mechanism of the neuroprotector action of this protein.
The neuroprotective activity of recombinant human erythropoietin (r-HuEpo) sorbed on poly(butyl)cyanoacrilate nanoparticles (EPO-PBCA) and on polylactic-co-glycolic acid nanoparticles (EPO-PLGA) has been studied on Wistar rats with intracerebral post-traumatic hematoma (model of hemorrhagic stroke) (IPH-HS) in comparison to native r-HuEpo. It is established that EPO-PBCA produced a protective effect in rats after IPH-HS that was manifested by a decrease in the number of animals with neurological disorders such as circus movement, paresis, and paralysis of hind limbs; the drug also improved coordination (rotating rod test), reduced the number of lost animals, and decreased the loss weight among survived rats. In addition, EPO-PBCA optimized the research behavior of rats with IPH-HS in the open field test and prevented amnesia of passive avoidance reflex (PAR), which was caused by the IPH-HS. These effects were manifested during a two-week observation period. EPO-PLGA has a similar but much less pronounced effect on the major disorders caused by IPH-HS. The efficiency of native r-HuEpo as a neuropotective agent was insignificant and only manifested by decrease in the number of lost animals with IPH-HS.
The aim of our study was to estimate the probability of the neoplasm recurrence in patients with T1 and T2 glottic carcinoma operated with CO2 laser microsurgery. We analyzed the material of 171 patients treated in the Otolaryngology Department of the Collegium Medicum Nicolaus Copernicus University between 1991 and 2003. The statistical method of logistic regression was used to estimate factors disposing the local recurrence of laryngeal cancer. We studied: age, sex, extent and location of the lesion, time up to recurrence, carbon granuloma, smoking cigarettes before and after the operation. We confirmed statistically significant correlation between the local recurrence and anterior commissure involvement.