[Cryohemosorption--a method of removal of lipoprotein-antibody immune complexes and other atherogenic substances in patients with atherosclerosis]. / Krioplazmosorbtsiia--metod udaleniia immunnykh kompleksov lipoproteid-antitelo i drugikh aterogennykh substantsii u bol'nykh aterosklerozom.

The efficacy of extracorporeal cryohemosorption was estimated in the treatment of atherosclerotic patients in terms of the autoimmune theory of the pathogenesis of this disease. There was a slight decrease in the plasma levels of total cholesterol and triglycerides, there was over 2-fold reduction in the plasma levels of fibrinogen and fibronectin. All major components of apo B-containing lipoproteins and immunoglobulin G were found as part of the cryoprecipitate. An extremely high concentration of lipid hydroperoxides in the precipitate suggest that cryoprecipitation removes not only autoimmune complexes, but highly-atherogenic peroxide-modified lipoproteins. The three-fold decrease in the levels of lipoprotein-antibody complexes resulted in lower atherogenicity of apo B-containing lipoproteins. It is suggested that the mechanism responsible for beneficial clinical action of cryohemosorption sessions is largely associated with the removal of autoimmune lipoprotein-antibody complexes and peroxide-modified apo B-containing lipoproteins than correction of lipid metabolism.

[Porton uptake by isolated chloroplasts during cyclic and non-cyclic electron transport catalyzed by photosystem I in the presence of ferredoxin]. / Pogloshchenie protonov izolirovannymi khloroplastami pri tsiklicheskom i netsiklicheskom transportakh elektronov, kataliziruemykh fotosistemoi I v prisutstvii ferredoksina.

Proton uptake by isolated chloroplasts during cyclic electron transport in the presence of ferredoxin and under NADP+ reduction from the ascorbate--TMPD donor pair under anaerobic conditions was studied. It was found that during cyclic transport the proton uptake is less intensive than under NADP+ reduction. In the presence of ATP the proton uptake is increased in the first case and is decreased in the second one. During cyclic transport in the presence of gramicidin D the proton uptake is completely suppressed and under NADP+ reduction is decreased down to 0,08--0,09 mk equiv H+ per mg of chlorophyll, irrespective of ferredoxin or NADP+ concentrations. The role of ferredoxin NADP+ reductase in a proton uptake by thylakoids is discussed.

[Cholinomimetic activity of acetylcholine and sebacinyldicholine derivatives with differing cationic group structures]. / Kholinomimeticheskaia aktivnost' proizvodnykh atsetilkholina i sebatsinildikholina s razlichnoi strukturoi kationnoi gruppy

The intrinsic alpha activities and the D2 (frog, m, rectus abdominalis) concentrations were estimated for different acetylcholine and sebacinylcholine derivatives. So were also the A2 values for antagonists and the affinity constants Kc for some partial agonists. The results obtained disprove Paton's "rate-theory". The relationship between the cholinergic activity and the volume of cationic groups was studied and it could not possibly be explained by the steric hindrance alone. It is suggested that certain hydrophobic radicals of the cationic groups contact the receptor surface outside the anionic centre. Such contacts prevent the cholinoreceptor to change its conformation and thus inhibit the depolarization of the membrane. An approximate estimation of the anionic site dimensions is given.

[Cholinesterase hydrolysis of acetylcholine derivatives with different structures of the ammonium grouping]. / Gidroliz kholinésterazami proizvodnykh atsetilkholina s razlichnoi ammonievoi gruppirovki

15 acetoxyethylenammonium compounds are studied as substrates for acetylcholinesterase (ACE) from bovine erythrocytes and for butyrylcholinesterase (BCE) from horse serum. Substitution of methyl groups of the ammonium grouping with other radicals and incorporation of onium nitrogen in the cycle resulted in the decrease of the hydrolysis rate under the action of BCE and ACE, the effect of BCE being more pronounced. The rate of the hydrolysis of N-acetoxyethylene-N-methylpiperidine iodide in the presence of ACE was 65 times as much as in the presence of BCE. This compound is a new specific substrate of ACE. Dipropylmethyl derivative turned not to be a good substrate for both enzymes. Dibutylmethyl and pyridinic derivatives were not attacked by ACE and BCE. Kinetic analysis of the compounds listed is performed, taking account of non-productive sorbtion. Possible role of hydrofobic regions in the orientation of substrates on the active surface of ACE and BCE is discussed.