Low-intensity lasers in pediatric oncology

The paper outlines the outcomes of treatment for complications associated with chemo- and radiation therapy in children with malignant neoplasms by using low-intensity laser radiation. The use of this therapy may reduce the duration of treatment of these complications by 1.5-2 times. The use of low-intensity laser radiation in the treatment of other complications that are common in pediatric oncological care is briefly described.     

A New Water-Soluble Thermosensitive Star-Like Copolymer as a Promising Carrier of the Chemotherapeutic Drug Doxorubicin

A new water-soluble thermosensitive star-like copolymer, dextran-graft-poly-N-iso-propilacrylamide (D-g-PNIPAM), was created and characterized by various techniques (size-exclusion chromatography, differential scanning calorimetry, Fourier-transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) spectroscopy). The viability of cancer cell lines (human transformed cervix epithelial cells, HeLa) as a model for cancer cells was studied using MTT and Live/Dead assays after incubation with a D-g-PNIPAM copolymer as a carrier for the drug doxorubicin (Dox) as well as a D-g-PNIPAM + Dox mixture as a function of the concentration. FTIR spectroscopy clearly indicated the complex formation of Dox with the D-g-PNIPAM copolymer. The size distribution of particles in Hank’s solution was determined by the DLS technique at different temperatures. The in vitro uptake of the studied D-g-PNIPAM + Dox nanoparticles into cancer cells was demonstrated by confocal laser scanning microscopy. It was found that D-g-PNIPAM + Dox nanoparticles in contrast to Dox alone showed higher toxicity toward cancer cells. All of the aforementioned facts indicate a possibility of further preclinical studies of the water-soluble D-g-PNIPAM particles’ behavior in animal tumor models in vivo as promising carriers of anticancer agents.     

Dynamics of the reactivity of cortical neurons to the repeating isolated action of L-glutamate and acetylcholine

A comparative analysis of the probability, directionality, and intensity of the changes in the average frequency of the baseline (BIA) and L-glutamate-induced (GlIA) and acetylcholine-induced (AChIA) impulse activity of individual neurons of the sensorimotor cortex of unanesthetized rats showed that the reactions to Gl are most variable; this is expressed in a significantly higher percent of neurons with potentiation of responses to Gl as compared with the proportion of cells which manifested an increase in the AChIA in the course of 20 applications of the mediators. As a result of 100 applications, the GlIA decreases most frequently; also, the degree of decrease in GiIA over the entire duration of the testing exceeds the degree of decrease in AChIA. It is more characteristic of ACh than of Gl to increase the level of BIA in the periods between the reactions to ACh, while in the case of repeated application of Gl, dynamics of decrease in BIA are characteristic. The results are discussed from the perspective of a possibly different functional role of the glutamatergic and cholinergic neuromediator systems in the cerebral cortex in the process of formation of the dynamics of neuronal activity during learning. M. V. Lomonosov Moscow State University. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 44, No. 1, pp. 135–142, January–February, 1994.