Intramolecular Hydrogen Bonding in N-Substituted 2-Chloroadenosines: Evidence from NMR Spectroscopy.

Two forms were found in the NMR spectra of N-substituted 2-chloroadenosines. The proportion of the mini-form was 11-32% of the main form. It was characterized by a separate set of signals in COSY, N-HMBC and other NMR spectra.

Enzymatic Synthesis of 2-Chloropurine Arabinonucleosides with Chiral Amino Acid Amides at the C6 Position and an Evaluation of Antiproliferative Activity In Vitro.

A number of purine arabinosides containing chiral amino acid amides at the C6 position of the purine were synthesized using a transglycosylation reaction with recombinant nucleoside phosphorylases. Arsenolysis of 2-chloropurine ribosides with chiral amino acid amides at C6 was used for the enzymatic synthesis, and the reaction equilibrium shifted towards the synthesis of arabinonucleosides. The synthesized nucleosides were shown to be resistant to the action of adenosine deaminase.

Encouraging Young Pediatric Surgeons and Evaluation of the Effectiveness of a Pediatric Endosurgery Workshop by Self-Assessment and an Objective Skill Validation System.

Japanese pediatric endosurgery experts conducted a workshop for young pediatric surgeons in Russia in collaboration with Russian expert pediatric surgeons. This study was aimed to develop a contributive workshop program and evaluate its impact on young pediatric surgeons. A 2-day pediatric endosurgery workshop was held in Moscow in February 2020.

Synthesis of 2-chloropurine ribosides with chiral amino acid amides at C6 and their evaluation as A adenosine receptor agonists.

A series of purine ribonucleosides bearing chiral amino acid amides at the C6 position of 2-chloropurine was synthesized. Molecular docking of the synthesized analogs of 2-chloroadenosine by their affinity for A adenosine receptors (AARs) was conducted. The investigation of AAR stimulating activity of synthesized nucleosides was carried out in a model of an isolated mouse atrium.

Multi-Enzymatic Cascades in the Synthesis of Modified Nucleosides: Comparison of the Thermophilic and Mesophilic Pathways.

A comparative study of the possibilities of using ribokinase → phosphopentomutase → nucleoside phosphorylase cascades in the synthesis of modified nucleosides was carried out. Recombinant phosphopentomutase from HB27 was obtained for the first time: a strain producing a soluble form of the enzyme was created, and a method for its isolation and chromatographic purification was developed. It was shown that cascade syntheses of modified nucleosides can be carried out both by the mesophilic and thermophilic routes from D-pentoses: ribose, 2-deoxyribose, arabinose, xylose, and 2-deoxy-2-fluoroarabinose.

Radical Dehalogenation and Purine Nucleoside Phosphorylase : How Does an Admixture of 2',3'-Anhydroinosine Hinder 2-fluoro-cordycepin Synthesis.

During the preparative synthesis of 2-fluorocordycepin from 2-fluoroadenosine and 3'-deoxyinosine catalyzed by purine nucleoside phosphorylase, a slowdown of the reaction and decrease of yield down to 5% were encountered. An unknown nucleoside was found in the reaction mixture and its structure was established. This nucleoside is formed from the admixture of 2',3'-anhydroinosine, a byproduct in the preparation of 3-'deoxyinosine.

[Certain specific features of the imprints of the blood-saturated head hair].

The present experimental study revealed a number of morphological features of the imprints of head hair of different length (varying from 0.5 to 24 cm). The imprints were shown to have a complicated many-component structure in which it was possible to distinguish between the central and peripheral portions.

[Experience of extracorporeal membrane oxygenation in critical care of respiratory failure in newborn with congenital diaphragmatic hernia in perinatal center].

The article deals with an experience of veno-arterial extracorporeal membrane oxygenation use in preterm infants with congenital diaphragmatic hernia during postoperative period in the perinatal center.

[Newly developed atrial fibrillation among patients under active observation by an outpatient clinic].

We carried out prospective cohort study of incidence of new cases of atrial fibrillation (AF) in a sample of Moscow population (patients under observation in our policlinic). Total incidence of AF between 2003 and 2009 was 7.7 per 1000 patient/years, it was higher among men than among women.

[Prevalence of atrial fibrillation among patients under observation by an outpatient clinic].

Prevalence of atrial fibrillation among patients attending our policlinic (2.44 and 3.78% in 2002 and 2009, respectively) was higher among men than among women and progressively increased with age achieving maximum in the group of patients aged more or equal 85 years.

[Detection of risk factors and early manifestations of cardiovascular diseases during ambulatory examination of working age persons].

We have studied prevalence of risk factors (RF) of cardiovascular diseases (CVD) recorded for statistical purposes in subjects of able bodied age during 10 year period of observation in a policlinic as well as prevalence of early and/or oligosymptomatic CVD manifestations in 11762 subjects of working age with RF of CVD development according to results of complex noninvasive examination of cardiovascular system in ambulatory conditions during the period from 2000 to 2009 year. Numbers of men and women were 45.3 and 54.

[The preparative method for 2-fluoroadenosine synthesis].

The preparative method for the synthesis of 2-fluoroadenosine starting from commercially available guanosine was developed. It included the intermediate formation of 2-amino-6-azido-9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)purine, which was isolated exclusively in the tetrazolo[5,1-i]-form {5-amino-7-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)-7H-tetrazolo[5,1-i]purine}. The latter compound was converted by the Schiemann reaction to 6-azido-2-fluoro-9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)purine, which was isolated at an 80% yield after careful optimization of the process.

[Carbon accumulation in soils of forest and bog ecosystems of southern Valdai in the Holocene].

Carbon stocks and accumulation rates in humus and peat horizons of the contiguous soil series of forest and bog ecosystems have been studied in the Central Forest State Biosphere Reserve (CFSBR, Tver region). Upland soil types (soddy podzolic, brown, and white podzolic) have been compared to waterlogged (peaty gley podzolic and peaty gley) and bog soils differing in trophic status, including those of raised, transitional, and lowland bogs. The results show that carbon stocks in mineral soils are many times smaller than in waterlogged soils and an order of magnitude smaller than in bog soils.

[The detection of bacteriogenic causes of opportunistic infections].

In order to select bacteriocin producing strains the screening of microorganisms from clinical material was perfomed. The delayed antagonism method was used. 154 strains were screened, 93 (60%) cultures produced antagonistic substances.

Immunogenicity of candidate DNA vaccine based on subtype A of human immunodeficiency virus type 1 predominant in Russia.

Human immunodeficiency virus (HIV)-1 subtype A strains circulating among the majority of HIVinfected individuals in the former Soviet Union (FSU) countries demonstrate low genetic diversity. The consensus sequence of the FSU region-specific isolate has been used for the candidate DNA vaccine development. We constructed recombinant plasmids with four viral genes: env (gp140), gag, pol (reverse transcriptase), and nef.

[Molecular basis of bacteriocins production and activity].

Bacteriocins--bacterial proteins or peptides--are envisaged as candidates for the next generation of effective antimicrobials. Analysis of characteristics of natural and genetically engineered bacteriocins with regard to the molecular basis of their production and activity has been performed. Most bacteriocins have narrow spectrum of the inhibitory activity.

[Biotechnological conditions of the synthesis of bacteriocins].

In this review information on the cultivation of bacteriocin-producing microorganisms belonging to different taxonomic groups are presented. The data on the influence of the most important biotechnological parameters (nutrient medium, temperature, pH, phase of growth, etc.) on the synthesis of bacteriocins are given.

[Sotahexal pharmacodynamics in patients with ischemic heart disease].

Therapeutic and prophylactic antiarrhythmic efficacy of sotalol hydrochloride (Sotahexal, "Hexal", Germany) and its effects in intracardiac hemodynamics and ECG parameters were evaluated in 95 patients with ischemic heart disease (IHD). The highest response to the drug was observed in ventricular extrasystoles, arterial flutter and fibrillation. Acute episodes of arrhythmia are managed by bolus administration of Sotahexal [correction of Hexal].

[Assessment of the informative value of neuron-specific enolase determined by the immunoenzyme method].

The diagnostic informative value of measurements of neuron-specific enolase (NSE) in health, pulmonary cancer (including small-cell one), 8 different diseases, and pregnant patients with gestation periods from 5 to 33 weeks was assessed. Comparison of the results in each of these 10 groups with the results in health controls did not reveal any appreciable differences for any of the groups or between the tested groups. The authors consider that NSE measurements cannot be recommended for use at other than cancer institutions.

[Development, course and late sequelae of diseases in workers engaged in organic glass production].

Health status was examined in workers engaged into methylmethacrylate-based organic glass production. The study supported that incidence, time and severity of occupational intoxications with methylmethacrylate depend on the level of its action. High (3-5-10 and more times exceeding the MAC) concentrations of methylmethacrylate induced the clinical signs of intoxication after 5 years of service.

[Clinical grading of paroxysmal atrial fibrillation in patients with ischemic heart disease].

The study into the nature and severity of clinical and electrocardiographic manifestations of paroxysms of atrial fibrillation in 213 patients with coronary heart disease identified the basic clinical and instrumental ECG signs (subjective attack tolerance, transient ECG changes, onset of left ventricular failure) that correspond to four stages of the natural history of paroxysmal atrial fibrillation. The use of the grades in clinical practice allows one to more definitely evaluate the status of patients, to correctly choose their management policy, and to define indications for hospitalization.

[Experience in long-term use of allapinin in polyclinical practice].

The authors summed up the practical experience gained in long-term maintenance treatment with allapinine, a new Soviet antiarrhythmic agent, given to 65 patients with various cardiac arrhythmias in the outpatient setting. The long-term allapinine use yielded good results: its efficacy was proved to be approximately equal (63% and 60%) in patients with ventricular or supraventricular extrasystoles, respectively, but it was 77% in those with paroxysmal atrial fibrillation. There were no decreases in antiarrhythmic activity of allapinine during its long-term therapy.