Effect of change in activity level of catecholaminergic systems on motor, respiratory, and cardiac activities in rat embryos

Parameters of motor, respiratory and cardiac activities were studied in rat embryos (E17-20) after changes in activity level of catecholaminergic systems. To produce conditions for excessive level of catecholamines, the animal were administered individually with preparation of L-DOPA at doses of 25, 50 and 100 mg/kg. Also studied was action of L-DOPA after blockade of D1-(antagonist - SCH-23390, 0.1 mg/kg), D2-(antagonist - sulpiride, 50 mg/kg) dopaminic, and beta2-(antagonist - propranolol, 1 mg/kg) adrenergic receptors. It was found out in E17-18 that the DOPA administration regardless of dose, while in E19-20 dose-dependently produces continuous generalized activity. Between E18 and E19, ontogenetically new is the appearance in 92 % of embryos of stereotypical head movements (circular movements, lateral and dorso-ventral flexions) following in the nearsecond rhythm. Injection of DOPA to rat embryos increased 2-6 times the number of respiratory movements by the gasping type in E17-20 and decreased the amount of episodes of continuous rhythmical respiration in E19-20. No significant heart rate changes were observed after introduction of DOPA to E17-20. There was noted a tendency for a weak acceleration of the heart rate. The changes in activities of the motor and respiratory systems due to a rise of catecholamine level are not connected with activation of the dopamine system, as they are not reduced by blockade of dopamine receptors.     

Characteristics of continuous cell line 293 used for preparation of antineoplastic agent Cancerolysin]

Certification of continuous cell 293 culture used for cultivation of antineoplastic preparation Cancerolysin was carried out. The seeding and working banks of cells 293 were established and deposited for storage at the Vector Centre. The cells were certified in accordance with the WHO requirements. The cell 293 culture was shown to have high proliferative activity; morphology typical of the line; its karyotype and enzymogram are typical of human cells; the culture is not contaminated with bacteria, fungi, mycoplasms and viruses including oncogenic ones; it has high virus-producing activity; it preserves stability of all the biological properties in long-term cultivation. The seeding and working cell banks were recommended for the use in production of drugs for the treatment of oncologic patients.     

Effect of gametocidal chromosome 4S' on the phenotype segregation ratio in genetic analysis of common wheat lines

Using experimental data on genetic analysis of introgressive lines for the character "hairy leaf sheath" controlled by the "cuckoo" chromosome 4S1, the algorithm for calculation of the theoretical segregation ratio in F2 was developed. Segregation distortion is caused by non-viability of the majority of gametes lacking the chromosome 4S1. The frequency of functioning gametes without the chromosome 4S1 is determined by the probability p versus the theoretically expected ratio 7 nonviable: 9 viable ones. Since segregation involves two characters, gamete viability and hairiness, the ratio 15 hairy: 1 hairless was used as a basis for search of the frequency p by maximum-likelihood method using 16 populations F2 from crossing the lines differing in the character studied.     

Dependence of the results of a genetic analysis of self-pollinating cereal species on the specificity of the mapping population

The available in literature information as for results of genetic analysis of several self-pollinating cereal species involving the use of plant lines with alien genetic material as the object of analysis is summarized. The restrictions caused by specificity of the investigated material as for the possible explanation of the obtained results are emphasized. Several suggestions concerning the preliminary study of introgressive plant lines before their including into experimental programs on genetic analysis are made.     

Methyl iodide reactions on the surface of mechanically pre-activated platinum(II) salt in the heterogeneous system: K2PtCl4 powder–MeI vapor

Mechanically pre-activated K₂PtCl₄ salt consumes methyl iodide producing methyl chloride at room temperature. The reaction mechanism includes the following steps sequence: oxidative addition of methyl iodide to platinum(II) complexes with intermediate formation of methyl platinum(IV) complexes and further decomposition of the latter in the course of innersphere reductive elimination yielding methyl chloride. The first step of the reaction proceeds owing to the assistance of active centers regenerated in the course of each event of MeI into MeCl transformation taking part in the chain halogen substitution process. It could be assumed that the role of active centers is played by coordinatively unsaturated platinum(II) complexes located on the surface. These species bearing a positive efficient charge can render electrophilic assistance for the nucleophilic substitution. The chain termination can be caused by recombination of coordinatively unsaturated platinum(II) complexes and interstitial chloride ions forming an inactive K₂PtCl₄ complex.