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Biomedical subjects

N F Miasoedov

Publications and source records attributed to N F Miasoedov.

At least 19 recordsLinked to original sources
PubMed2005

[Dependence of long-lasting effects of the ACTH(4-10) analogue semax on the time of its neonatal administration].

Long-lasting behavioural effects of chronic administration of synthetic ACT(4-10) analogue Semax (MEHFPGP) during early neonatal life were studied. The peptide was injected daily intraperitoneally in dose 0.05 mg/kg during the first, second or second-third weeks of postnatal development. It was shown that the peptide injections during the first week lead to a decrease and during second or second-third weeks--to an increase of exploratory activity in 4-8-week aged rats. Furthermore, the peptide adminictration at all times diminished anxiety and improved learning ability of adult rats. The data obtained show that Semax neonatal administration during the first three weeks of life modulates development of brain structures involved in regulation of exploration, anxiety and learning.

Adrenocorticotropic Hormone↗
PubMed2002

[Neuroprotective effects of semax in MPTP-induced disturbances of brain dopamine system].

Effects of an ACTH (4-10) analogue Semax (MEHFPGP) on behaviour of white rats with MPTP-induced disturbances of brain DA-system have been studied. It was shown that MPTP administration (25 mg/kg) reduced motor activity and auhmented the anxiety level in rats. Semax administration (daily intranasal 0.2 mg/kg) attenuated behaviour disturbances induced by neurotoxin. The observed protective action of Semax in rats with MFTP-induced DA system disturbances may be due to both its modulating influence on the brain DA system and peptide neuroprotective effects.

Administration, Intranasal↗
PubMed2000

[Solid phase catalytic hydrogen isotope exchange in dalargin].

A [3H]Dalargin preparation with a molar radioactivity of 52 Ci/mmol was obtained by the high temperature solid-state catalytic isotope exchange (HSCIE) of tritium for hydrogen at 150 degrees C. This tritium-labeled peptide was shown to completely retain its biological activity in the test of binding to opioid receptors from rat brain. The dissociation constant of the Dalargin-opioid receptor complex was found to be 4.3 nM. The dependencies of the chemical yield and the molar radioactivity on the reaction time and temperature of HSCIE were determined. The activation energy of the HSCIE reaction for the peptide was calculated to be 32 kcal/mol. The amino acid analysis showed that tritium is distributed between all the amino acid residues of [3H]Dalargin at the HSCIE reaction, with the temperature growth significantly increasing the total tritium incorporation and, especially, enhancing the radioactivity incorporation into aromatic residues.

Animals↗
PubMed2000

[Study of solid-phase catalytic isotopic exchange of hydrogen in alpha-conotoxin G1 under the effect of spillover-tritium].

Tritium-labeled alpha-conotoxin G1 with a molar radioactivity of 35 Ci/mmol and full biological activity (according to the binding to nicotinic acetylcholine receptor) was obtained by the high-temperature solid-state catalytic isotope exchange (HSCIE). The tritium distribution in the molecule of alpha-conotoxin G1 was revealed by 3H NMR spectroscopy. Tritium was found in all amino acid residues except for the Asn4-Pro5-Ala6 fragment. The data on the comparative reactivity of C-H bonds, the ab initio quantum-chemical calculation of the hydrogen exchange reaction, and the information on the spatial structures of alpha-conotoxin G1 in solution and in crystal state allowed us to establish that the reactivity of H atoms may be increased by their interaction with the electron donor O and N atoms at the transition state of the HSCIE reaction. A decrease in the rate of the HSCIE reaction could be caused by both a poor spatial accessibility of C-H bonds and a limited mobility of the peptide fragment containing these bonds.

Amino Acid Sequence↗
PubMed1999

[Clinico-immunobiochemical monitoring of factors of focal inflammation in the acute period of hemispheric ischemic stroke].

The changes of cytokinis status and C-reactive protein were evaluated in cerebrospinal fluid of 50 patients in the acute period of ischemic hemispheric stroke with consideration of influence of the remote consequences of the ischemia, established experimentally, on the mechanisms of cerebral infarction development as well as on the progression of both atherogenesis and vascular encephalopathy in the period after the stroke. Significance both of a surplus releasing of the proinflammatory cytokines and deficiency of the protective antiinflammatory and trophotropic factors in the development of an inflammatory response was established. Immunobiochemical criteria were proposed for grading of process for stroke course prediction and for recovery of the altered neurologic functions. More favourable prognosis was anticipated in the patients in which a the treatment started within of the "therapeutic window".

Acute Disease↗
PubMed1998

[Phosphorylation of 5'-O-phosphonylmethylthymidine and its incorporation into HeLa cells DNA].

[3H]5'-O-Phosphonylmethylthymidine with a specific activity of 71 Ci/mmol was obtained by isotope exchange. Its incubation with a HeLa cell culture resulted in the formation of [3H]-labeled 5'-O-(beta-phosphoryl-alpha-phosphonylmethyl)thymidine, 5'-O-(beta,gamma-diphosphoryl-alpha-phosphonylmethyl)thymidine, and [3H]DNA. This proved the ability of 5'-O-phosphonylmethylthymidine to undergo phosphorylation and incorporation into the DNA of human cells.

DNA, Neoplasm↗
PubMed1997

[Effectiveness of semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study)].

Efficiency of Semax (synthetic derivative of ACTH-4-10) was studied in 30 patients in acute period of hemispherical ischemic stroke. Control group consisted of 80 patients with the strokes analogous in severity and location of the damages and which were treated by conventional therapy. Different clinical rating scales were used for both objectivization of the severity of the patients' state and estimation of the degree of neurological defect. The control of Semax influence on the functional state of the brain included monitoring of EEG with mapping, repeated analysis of somatosensory evoked potentials and their mapping. It was established that including of Semax in combined intensive therapy of acute ischemic stroke had some influence on the rate of restoration of the damaged neurological functions in terms of increasing the regress of general cerebral and focal, especially motor disorders. The most effective daily doses were 12 mg for patients with strokes of moderate severity and 18 mg for patients with severe strokes (treatment course--5 and 10 days).

Acute Disease↗
PubMed1990

[Analysis of highly tritium-labeled alanine using 3H- and 1H-NMR].

A method has been developed for the analysis of deuterium oxide solutions of tritiated alanine eight-component isotopic mixtures by using high resolution 3H and 1H NMR spectra at frequencies 266.8 and 500.13 MHc, respectively. Approaches have been worked out for the determination of qualitative composition of the mixtures and spectral parameters.

Alanine↗
PubMed1990

[Distribution of labeled amino acids and delta-sleep inducing peptide in the body after instillation into the conjunctiva of the rabbit eye].

Dynamics of 3H-valine, 3H-glycine and 3H-DSIP distribution in various brain structures, tissues and liquids of an organism due to administration of these substances in eye conjunctive were studied in rabbits with scintillation spectrometry method. Marked amino acids and DSIP were observed in all substrates in 10 min after administration. Maximal activity was found in 2 h in the brain visual cortex and in 30 min in cardiac tissue, spleen and optical chiasma.

Amino Acids↗
PubMed1990

[Analysis of tritium-labeled glycine and alanine using 3H-NMR].

A method for analysis of three-component isotopic mixtures of tritium-labelled glycine and alanine in D2O solutions has been developed on the basis of high resolution 3H NMR spectra at 266.8 MHz. Determined were composition of the mixtures in molar per cent, as well as geminal and vicinal coupling constants (2JGly3H,H = -16.4 +/- 0.2 Hz; 2JAla3H,H = -14.0 +/- 0.5 Hz; 3JAla3H,H = 7.6 +/- 0.2 Hz) and isotopic shifts (0.21 +/- 0.001 ppm for glycine; 0.026 +/- 0.001 ppm for alanine).

Alanine↗
PubMed1989

[Preparation and properties of prostaglandin D2 labelled with tritium with high molar radioactivity].

Kinetic parameters of enzymatic and non-enzymatic transformations of [3H]prostaglandin H2 (PGH2) were determined; the maximum yield of [3H]PGD2 being obtained at the keobs/koobs ratio equal to 10. The two-stage enzymatic synthesis of [3H]PGD2 with high molar radioactivity (3.15 TBq/mmol) from [3H]arachidonic acid carried out. Its identity in properties to the natural PGD2 was shown in experiments on the inhibition of ADP-induced aggregation of thrombocytes and on enzymatic oxidation with 15-hydroxyprostaglandin dehydrogenase.

Adenosine Diphosphate↗
PubMed1988

[Chemical synthesis of tritium-labeled prostaglandins A, B and F].

Formation of prostaglandins A, B and F from prostaglandin E has been studied. Synthesis of tritium-labelled prostaglandins A1, A2, B1, B2, F1 alpha, F2 alpha, F1 beta, F2 beta of high molar radioactivity from highly labelled PGE1 and PGE2 is described.

Chemical Phenomena↗
PubMed1985

[Biosynthesis of tritium-labeled S-adenosyl-L-methionine in yeast cells].

Biosynthetic preparation of S-adenosyl-L-[methyl-3H]methionine from L-[methyl-3H]methionine by cultivation of diploid yeast Saccharomyces cerevisiae (methionine-auxotrophic) in a cultural medium with the high concentration of L-methionine is described. The radiochemical purity was over 95%. Biological activity of the preparations has been shown in transmethylation reactions in the presence of the yeast homocysteine-methyltransferase.

Kinetics↗
PubMed1985

[Synthesis of tritium-labeled N,N-dimethyl-2-phenylaziridinium and its reaction with acetylcholinesterase].

The synthesis of tritium-labeled N,N-demethyl-2-phenylaziridinium has been described. The specific radioactivity of the product obtained was 1,06 TBq/mmole. Kinetics of incorporation of this radioactive label into acetylcholinesterase of cobra venom (Naja naja oxiana) has been studied at 1,05 mM ligand concentration (25 degrees C, pH 7,50. 0,15 M phosphate buffer). Under these conditions two molecules of the radioactive label have been found to react with the enzyme. One molecule incorporates fast with half-life of 4,8 min, not affecting the enzymatic activity. Incorporation of the second label is a slow reaction with half-life of 6 hr and leads to complete inactivation of acetylcholinesterase. Molecular mass of the modified enzyme is 63 +/- 4 kDa and coincides with that of native one.

Acetylcholinesterase↗