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The long-term stress protective effects have been revealed among newly synthesized 9α-hydroxy-5α-ecdysteroids via a short-term heat stress tests (housefly Musca domestica). An increase as well as a reduce of protective effects for synthesized compounds have been demonstrated in comparison with the reference ecdysteroid 20-hydroxyecdysone, which obtained from the juice of Serratula coronata. The interdependence between stress- and geroprotective properties of the test models with their genotypic features and the structure of ecdvsteroids has been established.

We studied interaction between S-ethynyl ethers of phosphorus acids with cytochrome P-450 from rat liver and housefly abdomen. High thionic effect, i.e., considerable selectivity for the studied compounds in homoiotherms and arthropods, proved to the related to the triple bond in these compounds. Apparently, cytochrome P-450 participates in S-ethynylthiophosphates metabolism and breaks the P-S bond. This gives rise to "self-destroying" metabolites, namely, alkylthioketenes, which decelerate deactivation reactions through destruction of the corresponding isoform of cytochrome P-450 in the microsomal fraction in both homoiotherms and insects. However, the activation reaction goes much faster in insects than in homoiotherms.

Here we present data on the anticholinesterase activity of 58 synthesized ethers of phosphorus thioacids with an acetylene bond in the thioether group. Anticholinesterase activity of the compounds, with acetylene group in beta and especially alpha position, in the thioether radical is many times that of their saturated analogs. Reaction between the enzymes and acetylene organophosphorous inhibitors, as well as their saturated analogs, results in phosphorylated enzyme. The triple bond plays a significant role in the acceleration of cholinesterases phosphorylation. Antienzyme activity of acetylene organophosphorous inhibitors is discussed.

The insecticidal activity of Aikon, 10% wettable powder, and Carate, 5% emulsified concentrate, and 5% water soluble granules, (Zeneka Plant Protection, UK) was studied in laboratory and field tests. Their effective doses were 0.001-0.5 g/m2 (as calculated for active ingredients) for synanthropic insects (cockroaches, flies, fleas). The agents belong to moderate hazard class 3 substances. Their use has been approved by the Ministry of Health of the Russian Federation for treatment for non-living accommodations and subsidiary premises by specialists. Individual protective means should be used while contacting the agents.

Insecticidal gels containing the following agents as active ingredients: permethrin (0.4%), cipermethrin (0.1%), fenvalerate (0.5%), alpha-methrin (0.2%) were designed and studied under laboratory and field conditions. When applied to various surface types, the designed formulations of the gels caused 100% death of cockroaches, domestic flies, bed-bugs and fleas. The application rate is 2.5-10.0 g/m2 depending on the species of insects. The residual insecticidal action of gels on the surfaces is as long as 3 months. The designed formulations are approved by the Ministry of Health of Russia for their manufacture and application.

The aerosols derived from the designed 2% permethrine-containing pyrotechnical formulations (tablets and briquets) were tested for their effects in laboratory and field conditions. When tested in the chamber, its LC50 and LC99 were 0.056 and 0.43 mg/m2 (as calculated for the active ingredient), respectively, for Ae. aegypti mosquitos exposed to 15 min in the polycarprolactam plastic trap and 2.99 and 5.66 mg/m2 (for the active ingredient) for M. domestica flies exposed to an hour. LC99 for C. pipiens ranged 2 to 5 mg/m2 in the field conditions when treating the basements with varying airtightness. The effective dosage ensuring a 100% death of M. domestica in the animal-breeding premises of various types is 10 mg/m2 on an hour exposure.

Formulations of an insecticidal cipermethrine-based pencil were designed and tested in laboratory and field conditions. The formulation containing 0.3% of the active ingredient and a complex of filling components was found to have a high efficacy and a long-term residual action. The preparation "Virtox" has been allowed by the public health authorities for use in combating synanthropic cockroaches, bugs, fleas and other insects.

The direct correlative dependence between indices of absolute and relative number of two fly species calculated by Peterson's method is shown. The way of calculation of the absolute number of M. domestica and S. calcitrans and the receipt of the selection from subpopulations, which take in account peculiarities of adult fly distribution in different technological regimes of cattle keeping, peculiarities of daily activity and influence of temperature-photo factors on imago, are proposed. The attempt to study the structure and density of subpopulation of two fly species during one generation in North-West Russia is made. The date on mortality on different stage of life cycle are given.

Possibility of use of biological object as a detector of faint cosmophysical fields is discussed. The signals of free induction and electric echo caused by a short-term effect of light with an intensity of approximately 0.2 mWt/sm2 on biological systems were observed. The experiments with Blatella germanica, Muska domestica were performed in vivo and with red and green seaweeds and yeast cells in vitro. The signals were detected by means of the dielectric permeability measurement in a dynamic regime. Main features of the observed responses are described and assumption on mechanisms of their origin are given. An example of registration of the Lunar eclipse on a detector with in active element of Blatella germanica is given.

The resistance to chlorophos and some pyrethroids (permethrin, fenvalerate and ethofenprox) were determined in house fly imagos from Moscow, some towns of the Moscow Province (Dmitrov, Kolomna, Zagorsk and others). Tajikistan, Turkmenia and also Czechoslovakia. The tested populations from the USSR were highly resistant to chlorophos (more than 100 times) and susceptible or tolerant to pyrethroids. Czechoslovak populations were more resistant to pyrethroids.

A comparative analysis of the results of experimental trials of 12 new effective insecticide agents synthesized in the USSR and abroad, containing permethrin, deltamethrin, cypermethrin, cyfenothrin, etophenprox and neopinamine as active ingredients, against flies, mosquitos, fleas, bedbugs and cockroaches was made. The LD50 data in microgrammes per g and millilitres per litre and the LC50 data in grammes per sq m are given. All the tested preparations are allowed to use in medical desinsection practice.

Peculiarities of the development of room fly resistance during selection with permetrine have been studied in the laboratory conditions. A strain possessing a 50-fold level of resistance to permetrine has been obtained. A range of cross-resistance of this strain to insecticides of various chemical classes has been determined. It has been established that the basic mechanism regulating resistance to permetrine is an increase in cytochrome P-450 monooxygenases. Resistance can be overcome using a mixture consisting of permetrine and monooxygenase inhibitor piperonylbutoxide. The mixture retains its efficacy in almost 20 generations; later on the development of resistance to the mixture is accompanied by an increase in the level of resistance to nonsynergized piretroides and other preparations.

A new class of compounds: acetylenic amines, possessing structural similarity with the known inhibitor SKF-525A, and their saturated analogues, has been studied for its effect on the microsomal cytochrome P-450-dependent monooxygenases (MM). Significant differences in sensitivity of different substrate oxidation reactions in experiments with the mouse liver MM were observed. It was shown that the acetylenic amines investigated 13-30 times exceeded their saturated analogues as to the ability to inhibit aminopyrine and benzo[a]pyrene oxidation, and differed but slightly from their analogues with respect to p-nitroanisole and paraoxon oxidation. Benzo[a]pyrene hydroxylase of the house-fly abdomens was less sensitive to the compound investigated than that of the mouse liver, however, in contrast to it exhibited selectively to the diphenyl derivatives and not to the monophenyl ones.

Insecticidal and knock-down effects of eight pyrethroids, belonging to 2 types as to their chemical structure and specific action towards the nervous system, on the domestic flies' and German cockroaches' imago were assessed comparatively. Pyrethroids of the 2nd type, especially deltametrine, proved to be more effective against domestic flies as well as German cockroaches. Activity of the pyrethroids of the 1st type featured rapid knock-down effect and was practically independent from varying concentrations. The knock-down was reversible even at high concentrations. In case of the 2nd type of pyrethroids, the knock-down effect was concentration-dependent. Domestic flies, on the whole, were more sensitive to the effect of pyrethroids of the 1st type. The use of pyrethroids of the 2nd type against nonflying sinathropic insects would be advisable because they produce a higher insecticidal effect as well as irreversible knock-down.

Relative activity of chemicals and their specific activity coefficients are suggested as the criteria for comparative assessment of insecticidal properties of substances. Values of the afore-mentioned parameters of 34 chemicals compared to a standard are presented for 3 insect species: red cockroaches, house flies and bed-bugs.

Paper presents the results of the study of biological effect of precozen I--preparation with antijuvenile type of action on flies and mosquitoes. Parenteral administration resulted in reduced rate of imago hatching, alterations in female reproductive system, hereditary sterility. Treatment of flies' as well as mosquitoes' larvae caused various moult alterations: prologation of development stages, reduced chitinization. Multiple effects of precozen I on insects, characteristic both of hormonal preparations and chemosterilants, were observed.

Studies have been made of the effect of organophosphorus inhibitors (OPI) containing butynilic group in the detectable part of the molecule, and of their saturated analogues on cholinesterases from different species of mammals and arthropods. In all cases without a single exception, acetylene compounds exhibited higher anticholinesterase effect than saturated ones. The value of "acetylene effect" varied to a great extent and depended on both the structure of OPI and the source of cholinesterase, these data indicating the existence of differences in the structure of the active site in cholinesterases investigated. The acetylene effect was always higher in ethylmercapto-substituted OPI than in chloride-substituted ones. Among thiophosphates, the highest (7,600) effect was found for cholinesterase of the spider mite in the case of dimethyl esters. Among thiophosphonates, exceptionally high (38,000) effect was noted for cholinesterase from the head of the domestic fly when methylthiophosphonates were compared. In this pair of compounds, the inhibitory constant k2 for the cholinesterase of the fly by acetylene derivative was equal to 1.1 . 10(9).

The authors studied the disinfecting action of the vapour of tributyltin oxide in the aerosol chamber and came to the conclusion that the tin-organic compounds possessed a wide buicidal action, still inadequately used in practice. The mentioned vapour served as a disinfectant only in the presence of water vapour. Tribytyltin oxide (0.15% concentration) displayed an ovicidal action on the ova of Ascaris suum. Tributyltin laurate produced a good insecticidal effect on Musca domestica.

The miniature end-plate currents (MEPCs) and acetylcholine-induced current fluctuations were compared in experiments on fast and slow muscle fibres of lamprey, frog, chicken and rat. Simultaneous analysis of MEPCs decay time constant and mean life-time of single ionic channels suggests that the former is the main but not the sole factor determining the MEPCs duration. Additional factors, in particular, the relative insufficiency of acetylcholinesterase activity (AChE) are more important for the generation of the usual MEPSs in slow muscle fibres or the "giant" MEPCs in fast ones. Low activity of AChE favours the prominent asynchrony of interaction between acetylcholine molecules and cholinoreceptors causing prolongation of the time course of synaptic response. The mechanisms of MEPCs decay shortening induced by alpha-bungarotoxin or d-tubocurarine and the nonuniformity of different active spots of junctions are discussed.