ABSTRACT
Paclitaxel dosage form on nanoparticles of 200-300 nm based on lactic and glycolic acid copolymer was obtained by the co-precipitation method. The possibility of controlled release of paclitaxel at pH 7.4 for 24 h was studied in vitro. Studies on Jurkat/WT human T-lymphoblastic leukemia cells showed that incorporation of paclitaxel in the nanoparticles led to a 4-fold increase of its cytotoxicity (6.8×10(-6) M) in comparison with paclitaxel solution. The efficiency of compositions containing polysorbate-80 was comparable to that of non-modified nanoparticles containing paclitaxel.
Subject(s)
Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacology , Drug Delivery Systems/methods , Nanoparticles/chemistry , Paclitaxel/pharmacology , Antineoplastic Agents, Phytogenic/adverse effects , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/toxicity , Cell Line, Tumor , Drinking Behavior/drug effects , Glycolates/chemistry , Humans , Jurkat Cells , Lactic Acid/chemistry , Paclitaxel/adverse effects , Paclitaxel/toxicity , Polymers/chemistry , Polymers/pharmacology , Polysorbates/chemistry , Polysorbates/pharmacologyABSTRACT
Studies on rats showed that complete neurotoxin lesioning of the inferior olive obviated the possibility of developing and restoring previously learned operant balance reflexes. Motor deficit and compensatory-restorative processes in rats treated with 3-acetylpyridine and high section of the dorsolateral funiculus of the spinal cord depended directly on the level of disruption of the inferior olive. Prolonged observation of rats with incomplete lesions to the inferior olive revealed improvements in the compensation of motor lesions and stabilization of operant reflexes.
Subject(s)
Adaptation, Psychological/physiology , Conditioning, Operant/physiology , Neurotoxins/toxicity , Olivary Nucleus/physiology , Animals , Harmaline/toxicity , Male , Neural Pathways/cytology , Neural Pathways/physiology , Pyridines/toxicity , Rats , Red Nucleus/cytology , Red Nucleus/physiology , Spinal Cord/cytology , Spinal Cord/physiologyABSTRACT
The baseline impulse activity of neurons of the central nuclei of the cerebellum was investigated in awake cats under chronic experimental conditions through the use of various methods of statistical analysis. Differences were identified, along with the predominance of irregular impulse streams in the neurons of all the nuclei, in the relationship of individual varieties of the baseline activity of the neurons, both with respect to the pattern of the activity and with respect to the dynamics of the repetition of the interimpulse intervals, as well as with respect to other statistical characteristics of the distribution of the interimpulse intervals in each nucleus. It is hypothesized that the variations in the baseline impulse activity of neurons of individual nuclei are determined by their cytoarchitectonic features and by the varied distinctness of the correlating tonic afferent and cerebellar cortical influences.
