Results of the study of preventive effectiveness and side effects of anti-influenza lactoglobulin in controlled epidemiologic trial]

Prophylactic activity and side action of antiinfluenza lactoglobulin were studied under conditions of controlled epidemiological trial in 6361 persons during the epidemiological rise of influenza incidence. The data obtained pointed to the absence of any protective effect of antiinfluenza lactoglobulin. Marked allergenic properties of lactoglobulin and development of sensitization in the persons under observation were found during the study of the side-effect of the preparation. Thus, the absence of prophylactic efficacy and the sensitizing action of antiinfluenza lactoglobulin pointed to the inexpediency of its use for prophylactic and therapeutic purpose.     

Effect of ethionine on dolichyl phosphate-dependent transglycosylation reactions in rat liver

Dolichyl phosphates of different chain length (C35, C55 , C75 , Dol-mixture of C90 , 95, 100, 105 and C110 ) were tested as lipid acceptors in transglycosylation reactions. In the absence of exogenously added dolichyl phosphates there were no differences in the rate of synthesis in liver of dolichyl phosphate mannose, dolichyl phosphate glucose and dolichyl pyrophosphate N-acetylglucosamine between normal and ethionine-treated animals. Addition of exogenous dolichyl phosphates of different chain length stimulated the synthesis of dolichyl phosphate mannose and dolichyl pyrophosphate N-acetyl-glucosamine 2 to 4 times depending on the chain length of dolichols , both in normal and ethionine-treated animals. In liver of ethionine-treated rats the formation of dolichyl phosphate glucose was not stimulated. Following ethionine treatment the concentration of free and esterified with fatty acids dolichols was increased.     

Crystallins in the differentiation and regeneration processes of the crystalline lens in amphibia

The published and authors' data have been summarized on (1) the spectrum and properties of crystallins in different amphibian species, (2) localization and synthesis of crystallins in different cellular compartments of the adult amphibian lens, (3) dynamics of crystallin formation during embryogenesis and (4) lens regeneration from tissues of the larval and adult amphibian eyes. The necessity of more detailed studies of crystallin synthesis during embryogenesis and lens regeneration using molecular biological and biochemical methods is stressed. The significance of this approach is illustrated by the pioneering data of Soviet scientists on crystallin polypeptides and corresponding mRNAs in development of Rana temporaria obtained with the use of DNA-RNA hybridization and immunoelectroblotting.     

Does calmodulin participate in the regulation of the Ca-pump of erythrocytes in vivo?

Using a highly effective chelator of Ca2+ and 45Ca, the concentration of Cai2+ in human and rat erythrocytes was measured both at normal and accelerated Ca2+ influx into the cells. No effect of the calmodulin-dependent reaction inhibitor R24571 was observed. The Ca-ATPase from saponin-treated erythrocytes was characterized by a high affinity for Ca2+ (K 0.5-0.7 microM). This value is 2-3 times as low as that for Ca2+ concentration causing a 50% increase of the Ca-ATPase activity in erythrocyte ghosts obtained during hypoosmotic hemolysis. The Ca-ATPase activity in saponin-treated erythrocytes did not change either under the effect of calmodulin or by R24571. It was assumed that calmodulin did not participate in the regulation of the Ca2+-pump operation in erythrocytes in vivo.     

Dynamics of adenylate cyclase desensitization during long-term exposure to the hormone

The dependence of adrenal gland adenylate cyclase desensitization on the dose of in vivo injected ACTH, the time of occurrence and duration of the enzyme refractory period and the dependence of desensitization on the number of ACTH injections were analyzed. The experiments were carried out on guinea pigs injected with prolonged action preparations of ACTH (4 and 6 units) daily for 1-6 days. Intramuscular injections of ACTH caused adenylate cyclase refraction to the repeated action of the hormone. The effect of desensitization was the most conspicuous within the first few hours after hormone injection. The decrease of adenylate cyclase sensitivity and the duration of this effect were found to depend on the ACTH dose as well as on the number of injections. It has been shown for the first time that a single in vivo injection of 0.9% NaCl causes short-term desensitization of adenylate cyclase to the repeated action of much higher doses of ACTH in vitro, presumably due to endogenous ACTH release in response to weak stress exposure. The periodicity of changes in adenylate cyclase sensitivity upon prolonged hormone administration is discussed. Sensitization of the enzyme upon daily short-term exposure to physiological doses of ACTH (administration of 0.9% NaCl for 6 days) was revealed.     

Structural identity of active sites of RNases

It is known that the affinity of all nucleoside monophosphate isomers for RNAase active sites increases in the following order: 5'-NMP----3'-NMP----2'-NMP, irrespective of the RNAase type (pyrimidine-specific, guanine-specific or non-specific) and stage of activity (transferase, hydrolase). It is known also that the nucleotides with the same degree of isomerism have substantially the same conformation. It was thus supposed that the structure of active sites of RNAase has common features with a closer similarity in case of pyrimidine-specific (EC 3.1.4.22), guanine-specific (EC 3.1.4.8) and non-specific (EC 3.1.4.23) RNAases.     

Molecular tools for the study of calcium channels: synthesis and evaluation of biological activity of new derivatives of 4-aryl-1,4-dihydropyridine groups

The synthesis and biological activity of some novel analogs of the calcium channel blocker nifedipine, i.e., derivatives of 2.6-dimethyl-3.5-diethoxycarbonyl-4-(3-nitrophenyl)-1.4-dihydropyridine (DHP) were studied. One radioactive and two photoactivable DHP derivatives were obtained. DHP hemisuccinate was used to prepare an affinity matrix, DHP-Sepharose as well as a DHP-albumin conjugate; the latter was used for anti-DHP antibodies generation in rabbits. All novel DHP derivatives were obtained from a single key 3-hydroxycarbonyl DHP derivative, and they comprise a series of necessary tools for the study and isolation of membrane calcium channels.