Results of long-term radiation environment monitoring by the Russian RMS system on board Zvezda module of the ISS.

The Radiation monitoring system (RMS) continuously operated in various configurations since the launch of the Zvezda module of the International Space Station (ISS). The RMS consisted of 7 units, namely: the R-16 dosimeter, 4 DB-8 dosimeters, utility and data collection units. The obtained data covers a time of 22 years.

[Effects and mechanism of action of synthetic peptide octarphin].

We have synthesized the peptide TPLVTLFK corresponding to the β-endorphin fragment 12-19 (the name given by the authors - octarphin), and its analogs (LPLVTLFK, TLLVTLFK, TPLVLLFK, TPLVTLLK, TPLVTLFL). The peptide octarphin was labeled with tritium (the specific activity of 28 Ci/mmol) and its binding to the murine peritoneal macrophages has been studied. [(3)H]Octarphin was found to bind to macrophages with high affinity (K(d) = 2.

[Role of the brain dopaminergic and serotoninergic systems in psychopharmacological effects of ladasten and sydnocarb].

The influence of ladasten and sydnocarb on dopamine and serotonin receptors and the biosynthesis and re-uptake of dopamine and serotonin has been studied. It is established that both drugs do not produce any direct effects on dopamine D1, D2, and D3 receptors in rat striatum as well as on serotonin 5-HT1A and 5-HT2A receptors in rat frontal cortex in vitro. Ladasten in a single dose of 50 mg/kg (i.

[Stress-protective activity of the CH3CO-Lys-Lys-Arg-Arg-NH2 synthetic peptide (protektin)].

The CH3CO-Lys-Lys-Arg-Arg-NH2 peptide (the author has named it protectin) was synthesized, and its activity was studied during different stress actions. Protectin was found to normalize the content of corticosterone and adrenalin in adrenal glands and blood after its intranasal administration to rats one day before a cold or heat shock, or hypobaric hypoxia at doses of 1-10 microg/animal and after its intravenous administration just after acute hemorrhage at doses of 0.5-2 microg/animal.

[Ligands of glutamate and dopamine receptors evenly labeled with hydrogen isotopes].

A reaction of high-temperature solid-phase catalytic isotope exchange (HSCIE) was studied for the preparation of tritium- and deuterium-labeled ligands of glutamate and dopamine receptors. Tritium-labeled (5S,10R)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclopenten-5,10-imine ([G-(3)H]MK-801) and R(+)-7-hydroxy-N,N-di-n-propyl-2-aminotetraline ([G-(3)H]-7-OH-DPAT) were obtained with a specific activity of 210 and 120 Ci/mol, respectively. The isotopomeric distribution of deuterium-labeled ligands was studied using time-of-flight mass-spectrometer MX 5310 (ESI-o-TOF) with electrospray and orthogonal ion injection.

[Solid phase reaction of hemoglobin with spillover hydrogen].

The reaction of high-temperature solid-state catalytic isotope exchange (HSCIE) between bovine hemoglobin and spillover hydrogen (SH) was studied. It was shown that, in the field of subunit contact, there is a significant decrease in ability for hydrogen exchange by SH. A comparison of the distribution of the isotope label in the hemoglobin alpha-subunit was carried out for the HSCIE reaction with the hemoglobin complex and with the free alpha-subunit.

[Stress-protective effect of the KKRR synthetic peptide corresponding to the 15-18 sequence of human adrenocorticotropic hormone].

The activity of the KKRR synthetic peptide corresponding to the 15-18 sequence of human adrenocorticotropic hormone (ACTH) and its analogues KKKK, RRRR, RRKK, kKRR, KkRR, KKrR, and KKRr (amino acid residues of the D configuration are designated by small letters) was studied in vivo on rats under cold and heat shock. Intranasal administration of the KKRR peptide at doses of 2-10 microg/animal 1 day before the shock was found to prevent a dramatic increase in the level of corticosterone in rat adrenal glands and blood plasma caused by the temperature effect. Amino acid substitutions in the KKRR peptide were shown to result in an abrupt decrease in its activity.

[A comparative analysis of distribution of glyprolines administered by various routes].

The distribution of the glyprolines Pro-Gly-Pro and Thr-Lys-Pro-Arg-Pro-Gly-Pro (Selanc) was analyzed and compared in tissues of rat organs after different ways of their administration using the peptides uniformly labeled with tritium. Comparative data on changes in concentrations of the peptides in the rat organs after their intraperitoneal, intranasal, intragastric, and intravenous administration are given. The intranasal administration of both peptides was shown to be optimal for the delivery of glyproline molecules in the CNS.

[Interaction of the synthetic immunomodulatory dipeptide bestim with murine macrophages and thymocytes].

The tritium-labeled dipeptide bestim (gamma-D-Glu-L-Trp) with a specific activity of 45 Ci/mmol was obtained by high-temperature solid-state catalytic isotope exchange. It was found that [3H]bestim binds with a high affinity to murine peritoneal macrophages (Kd 2.1 +/- 0.

[Binding of beta-endorphin and its fragments to the non-opiod receptor of murine peritoneal macrophages].

The tritium-labeled selective agonist of the nonopioid beta-endorphin receptor the decapeptide immunorphin ([3H]SLTCLVKGFY) with a specific activity of 24 Ci/mmol was prepared. It was shown that [3H]immunorphin binds with a high affinity to the non-opioid beta-endorphin receptor of mouse peritoneal macrophages (Kd 2.4 +/- 0.

[Regulatory peptides and psychomotor development in infants].

Regulatory peptides (RP) are an important homeostatic factor. The maternal organism and placenta are substantial sources of RP for fetus during the prenatal period. Not only endogenous, but also exogenous RP play an important role during early postnatal period.

[Stress-protective effect of the synthetic ACTH-like peptide leucocorticotropin].

We found that the tritium-labeled synthetic ACTH-like octapeptide leucocorticotropin corresponding to the 81-88 sequence of the precursor of human interleukin-1alpha ([3H]GKVLKKRR) is bound by the ACTH receptor of rat adrenal cortex with a high affinity and specificity (Kd 2.2 +/- 0.1 nM).

[Reculatory fragments of collagen in gastric mucosa homeostasis].

The new glyproline family was distinguished from the regulatory peptides recently. It includes the simplest proline- and glycine-containing peptides: PG, GP, PGP, and respective peptides with hydroxylated proline residues. Glyproline's bioactivity covers many important systems of the body including suppression of some reaction in the blood coagulation and platelet aggregation and gastric mucosal maintenance.

[Short peptide fragments with antiulcer activity from a collagen hydrolysate].

A peptide acidic hydrolysate of collagen (PHC) was obtained under conditions (4 N HCl) ensuring the predominant formation of short peptides, glyprolines. They were separated and their antiulcer activity was studied. Thirty individual peptides with molecular masses of 174-420 amu were isolated from the PHC by HPLC.

[Evenly tritium-labeled peptides and their in vivo and in vitro biodegradation].

Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50-150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with spillover tritium. The distribution of the isotope label among all amino acid residues of these peptides allows the simultaneous determination of practically all possible products of their enzymatic hydrolysis.

[Solid phase isotope exchange with spillover hydrogen in amino acids, peptides, and proteins].

We summarize here information on the theoretical and experimental study of high-temperature (150-200 degrees C) solid phase catalytic isotope exchange (HTSPCIE) carried out with amino acids, peptides, and proteins under the action of spillover hydrogen. Main specific features of the HTSPCIE reaction, its mechanism, and its use for studying spatial interactions in polypeptides are discussed. A virtually complete absence of racemization makes this reaction a valuable preparative method.

[Pharmacokinetics of glyprolines (PGP) upon intragastric administration].

The pharmacokinetics of glyprolines upon intragastric administration in rats was studied by monitoring the content of tritium-labeled PGP in the blood plasma and protein, in organs (for 5 h), and urine (for 8 h). The maximum radioactivity (2.25% of the introduced level) in the blood plasma was observed 15 min after administration of [3H]-PGP.

[The binding of Semax, ACTH 4-10 heptapeptide, to plasma membranes of the rat forebrain basal nuclei and its biodegradation].

The binding characteristics of the peptide Semax (Met-Glu-His-Phe-Pro-Gly-Pro) to plasma membranes of basal nuclei of the rat forebrain and the dynamics of its degradation during its incubation with these membranes were studied. Binding of the homogeneously labeled [G-3H]Semax was shown to be time-dependent, specific, and reversible. Specific binding of the heptapeptide depended on calcium ions and was characterized by the dissociation constant of the ligand-receptor complex Kd = 2.

[Leu-enkephalin homogeneously labeled with tritium in studying the Selank inhibiting effect on the enkephalin-degrading enzymes of human plasma].

A method of analysis of enkephalinase activity in blood plasma based on the application of Leu-enkephalin generally labeled with tritium at all its amino acid residues was developed. The method allows the simultaneous estimation of activity of several peptidases in microquantities of tissues. [G-3H]Leu-enkephalin was prepared by the method of solid phase catalytic isotope exchange (120 Ci/mmol) and subjected to proteolysis by the treatment with blood plasma.

[Highly stable regulatory oligopeptides: experience and applications].

The most stable regulatory peptides (RP) including the new family of RP (glyprolines) and derivatives of hybrid peptide MEHFPGP are characterized. High ability of glyprolines to penetrate into the blood-stream through the gastrointestinal tract is demonstrated. Antiulcer, antithrombotic and antidiabetic activities of glyprolines were discovered in experiments on white rats.

[Effect of new peptide bioregulators livagen and epitalon on enkephalin-degrading enzymes in human serum].

The effect of new peptide bioregulators--Livagen (Lys-Glu-Asp-Ala) and Epitalon (Ala-Glu-Asp-Gly)--on endogenous opioid system was studied, particularly, their ability to change the activity of enkephalin-degrading enzymes from serum and interact with opioid receptors of the brain membrane fraction. Enkephalinase activity was assayed in vitro by the rate of 3H-Leu-enkephalin hydrolysis in the presence of the tested peptides. Livagen and Epitalon inhibited enkephalin-degrading enzymes from human serum.

[Comparative study of the distribution of 3[H]-himantane in the brain structures and the thymus of rats].

Dynamics of distribution of 3[H]-labeled himantane (N-(adamant-2-yl) hexamethyleneimine hydrochloride), a new drug possessing antiparkinsonian and immunostimulant activity, was monitored over a time period of 10 days after single injection (10 mg/kg, i.v.) in rats.

[Serodiagnosis in salmonelloses].

A method for preparing antigenic hydrosol diagnostic agent for hydrosol agglutination test is suggested. Efficiencies of hydrosol agglutination and passive hemagglutination tests in detection of antibodies to salmonella are compared. Arbitrary diagnostic titers are determined, diagnostic value of hydrosol agglutination test is assessed, time course of accumulation of specific antibodies is traced, and optimal terms of serological diagnosis of salmonellosis in patients of different age are determined.