A study of hydrolysis of various synthetic peptides with gastrointestinal enzymes using thin-layer chromatography

Hydrolysis in vitro of alpha- and epsilon-peptide bonds of synthetic amino acids and peptide substrates,--models of protein fragments, with digestive enzymes was studied. The kinetics of hydrolysis was studied by quantitative thin-layer chromatography followed by densitometric analysis of the chromatographic patterns. The rate constants of hydrolysis of Phe-Lys, Gly-Lys dipeptides and their epsilon-acetyl and epsilon-succinyl derivatives with leucine aminopeptidase and pancreatic enzymes were calculated. epsilon-Acyl residues of the substrates failed to split off under these conditions. The digestive enzymes hydrolysed the alpha-peptide bonds adjacent to the acylated lysine. Hydrolysis of epsilon-acetyl substrates proceeded faster as compared to epsilon-succinyl derivatives.     

Neuropsychological approach to analysis and estimation of visual imagination

Connections between visual imagination and verbal presentation was studied in normal conditions and in organic and functional impairment of mental activity in children and adults. Criteria for the analysis of visual imagination were designed. The significance of various forms of its disturbances for the differential neuropsychological diagnosis of organic and psychogenic diseases as well as for revealing the social disadaptation of adolescents was demonstrated.     

Proliferation of normal and tumor cells in presence of serum of patients with breast carcinoma after phototherapy with visible and near infrared light

The low-intensity visible (LV) and near infrared (NI) irradiation from laser and nonlaser sources has been used to treat oncologic patients with complications that develop after surgical tumor resection and chemo- and radiation therapy. However, the question of the character of effect of this physiotherapeutic method on the proliferative activity of tumor cells in patients with oncopathology and cells that participate in the wound healing processes, i.e., fibroblasts (FBs) and keratinocytes (KCs), remains unanswered. In the present work, we studied the effect of the course of irradiation of patients with breast carcinoma (BC) in the postsurgical period with visible and NI light (480–3400 nm, 95% polarization, 40 mW/cm², 12 J/cm²) on the proliferative activity of primary cultures of human FBs and KCs and of several cultures of human tumor cells (BT-474, HBL-100, Hs578T, and A431) in the presence of the blood serum of patients with BC. A 7-day course of phototherapy leads to an increase in the proliferation of FBs (compared to the initial level) and KC (compared to the postsurgical level) by 22 and 28%, respectively. The 7-day course of phototherapy leads to an increase in the proliferation of FBs (compared to the initial level) and KsC (compared to the postsurgical level) by 22 and 28%, respectively. The proliferative activity of BT-474, Hs578T, and A431 tumor cells decreased compared to the presurgery (initial) level by 31.5, 8.97, and 6.47%, respectively, and as compared to the postsurgical level by 32, 16, 8.65, and 6.26% for the BT-474, HBL-100, Hs578T, and A431 cells, respectively. The obtained results argue in favor of the oncologic safety of the course of phototherapy with visible and NI light of BC patients during postsurgical rehabilitation.