Ligands with affinity to specific sequences of DNA base pairs. X. Synthesis and binding of netropsin analogs, containing a chelating copper ion peptide, with DNA

An analogue of netropsin has been synthesized consisting of two N-propylpyrrolcarboxamide units linked covalently to a copper-chelating tripeptide Gly-Gly-L-His by means of two and three glycine residues. Binding to DNA and synthetic polynucleotides of netropsin analogue containing three glycine residues between Gly-Gly-L-His tripeptide and the N-end of netropsin analogue (His-Nt) has been studied. It is shown that this netropsin analogue chelates a copper ion with 1:1 stoichiometry, similar to a free Gly-Gly-L-His peptide. It is found that this netropsin analogue occupies 3 to 4 base pairs upon binding to poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers, irrespective of whether it binds in Cu(2+)-ligated or unligated forms. Binding constants and binding site sizes have been calculated for netropsin analogue complexes with DNA, poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers at the [Cu2+]/[His-Nt] ratio equal to 0 and 1.0. In the three-component system including His-Nt and Cu(2+)-His-Nt, cooperative effects are recognized which can be explained by heterodimer generation on interaction of His-Nt and Cu(2+)-His-Nt at adjacent binding sites.     

Hyperbaric oxygenation and current methods of detoxication in multimodal intensive therapy of diffuse peritonitis

The course of diffuse peritonitis has been followed up in 219 patients, 20 of these with the reactive, 165 with toxic, and 34 with the terminal stages of the condition. Multiple-modality intensive care included, besides routine therapy, local abdominal hypothermia, UV irradiation of autoblood (UVIAB), and, if indicated, hyperbaric oxygenation (HBO) and hemoperfusion. In addition to clinical tests, immunobiochemical monitoring of medium-molecular peptide fractions MM1 and MM2 and index of their distribution, as well as of circulating immune complexes CIC1 and CIC2 and the levels of immunoglobulins IgA, IgM, and IgG were the criteria for assessing the severity of intoxication and efficacy of intensive care and for predicting the course and outcome of the disease. The results indicate that HBO in combination with hemoperfusion, local abdominal hypothermia, and UVIAB have a positive impact on the clinical picture of the disease and on the time course of markers of endogenous intoxication and humoral immunity in patients with the terminal and toxic phases of diffuse peritonitis.     

Clinical computed tomographic correlations in children from a group at high risk for schizophrenia

Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children.     

Effect of loading rate on microstructural features of steel failure in crack propagation

A quantitative and qualitative fracture analysis has been carried out on 40Kh and St.3 steel specimens. The existence of a certain loading rate threshold has been established whose exceeding changes the regularities of the effect of the loading rate on the shape and parameters of the fracture microrelief. This corresponds to the speed dependence of dynamic crack resistance of steel.Translated from Problemy Prochnosti, No. 2, pp. 20–24, February, 1991.     

The relationship between lipid peroxidation and life span in Drosophila melanogaster

Using Drosophila lines pre-selected for adaptive characters, studies have been made on the relationship between the intensity of lipid peroxidation and life span in flies of different genotype, age and physiological condition. It was shown that the intensity of lipid peroxidation depends mainly on different factors (sex, age, virginity) in different lines. No expected negative correlation was found between the level of lipid peroxidation and life span in hybrids between two inbred lines. The intensity of lipid peroxidation was inherited like a dominant character, the dynamics of aging--like a codominant one in females and superdominant in males. Both the level of lipid peroxidation and life span appeared to be sex-dependent characters.     

Hydrophosphorylation of vinyl sulfides with elemental phosphorus in the KOH/DMSO(H2O) system: synthesis of 2-alkyl(aryl)thioethylphosphinic acids

Elemental phosphorus (red or white) reacts with alkyl and aryl vinyl sulfides in the superbase system KOH/DMSO(H₂O) at 75–120°C for 2–3?h to afford 2-alkyl(aryl)thioethylphosphinic acids in a yield of up to 31%.     

The interaction of homogeneous motor conditioned reflexes during conditioned-reflex switchover: the transfer of learning and interference

The dynamics of elaboration of the conditioned switchover (CSw) of homogeneous motor conditioned reflexes (CR) with different lateralization of the motor skill was studied in rabbits. Learning of CSw was shown to pass three basic stages characterized by different degree of consolidation of the CRs, by interaction between the two CRs, and by manifestation of CSw. Stages I and II reflected the process of afferent and efferent generalization of CRs and CSw, stage III was associated with specialization of CRs and CSw. Both positive and negative transfer of motor learning as well as interference between the two motor skills took place during CSw elaboration. The highest rate of CSw acquisition was observed in rabbits displaying positive motor transfer.