Lifetime Prevalence of Transient Loss of Consciousness in an Urban Russian Population / Prevalência de Perda de Consciência Temporária em População Russa Urbana

Abstract Background: Most international studies on epidemiology of transient loss of consciousness (TLC) were performed many years ago. There are no data about the lifetime prevalence of TLC in Russia. Objective: To identify the lifetime prevalence and presumed mechanisms of TLC in an urban Russian population. Methods: 1796 individuals (540 males [30.1%] and 1256 females [69.9%]) aged 20 to 69 years (mean age 45.8 ± 11.9 years) were randomly selected and interviewed within the framework of multicentre randomised observational trial. Results: The overall prevalence of TLC in the studied population was 23.3% (418/1796), with the highest proportion (28%) seen in 40-49 year age group. TLC was significantly more common in women than in men (27.5% vs 13.5%). The mean age of patients at the time of the first event was 16 (11; 23) years, with 333 (85%) individuals experiencing the first episode of TLC under 30 years. The average time after the first episode of TLC was 27 (12; 47) years. The following mechanisms of TLC were determined using the questionnaire: neurally-mediated syncope (56.5%), arrhythmogenic onset of syncope (6.0%), nonsyncopal origin of TLC (1.4%), single episode during lifetime (2.1%). Reasons for TLC remained unidentified in 34% cases. 27 persons (6.5%) reported a family history of sudden death, mainly patients with presumably arrhythmogenic origin (24%). Conclusion: Our findings suggest that the overall prevalence of TLC in individuals aged 20-69 years is high. The most common cause of TLC is neurally-mediated syncope. These data about the epidemiology can help to develop cost-effective management approaches to TLC.

Resumo Fundamento: A maioria dos estudos internacionais sobre epidemiologia da perda de consciência temporária (PCT) foi realizada há muitos anos. Não há dados sobre sua prevalência ao longo da vida na Rússia. Objetivo: Identificar a prevalência ao longo da vida e os supostos mecanismos da PCT em uma população russa urbana. Métodos: 1.796 indivíduos (540 homens 30,1% e 1.256 mulheres 69,9%) com idade entre 20 e 69 anos (idade média, 45,8 ± 11,9 anos) foram selecionados aleatoriamente e entrevistados no contexto de um estudo multicêntrico randomizado observacional. Resultados: A prevalência global de PCT na população estudada foi 23,3% (418/1.796), sendo a mais alta proporção (28%) observada na faixa etária de 40-49 anos. PCT foi significativamente mais comum nas mulheres (27,5% vs 13,5%). A idade média dos pacientes por ocasião do primeiro evento foi 16 (11; 23) anos, com 333 (85%) indivíduos experienciando o primeiro episódio de PCT antes dos 30 anos. O tempo médio após o primeiro episódio de PCT foi 27 (12; 47) anos. Os seguintes mecanismos de PCT foram determinados usando-se um questionário: síncope neuromediada (56,5%), síncope de origem arritmogênica (6,0%), PCT de origem não sincopal (1,4%), episódio único durante a vida (2,1%). A causa de PCT não foi identificada em 34% dos casos, sendo que 27 pacientes (6,5%) relataram história familiar de morte súbita, principalmente aqueles com PCT de suposta origem arritmogênica (24%). Conclusão: Nossos achados sugerem uma alta prevalência global de PCT em indivíduos com idade entre 20 e 69 anos. A causa mais comum de PCT é a síncope neuromediada. Esse dado sobre a epidemiologia pode contribuir para o desenvolvimento de abordagem custo-efetiva para PCT.

Lifetime Prevalence of Transient Loss of Consciousness in an Urban Russian Population.

BACKGROUND: Most international studies on epidemiology of transient loss of consciousness (TLC) were performed many years ago. There are no data about the lifetime prevalence of TLC in Russia. OBJECTIVE: To identify the lifetime prevalence and presumed mechanisms of TLC in an urban Russian population. METHODS: 1796 individuals (540 males [30.1%] and 1256 females [69.9%]) aged 20 to 69 years (mean age 45.8 ± 11.9 years) were randomly selected and interviewed within the framework of multicentre randomised observational trial. RESULTS: The overall prevalence of TLC in the studied population was 23.3% (418/1796), with the highest proportion (28%) seen in 40-49 year age group. TLC was significantly more common in women than in men (27.5% vs 13.5%). The mean age of patients at the time of the first event was 16 (11; 23) years, with 333 (85%) individuals experiencing the first episode of TLC under 30 years. The average time after the first episode of TLC was 27 (12; 47) years. The following mechanisms of TLC were determined using the questionnaire: neurally-mediated syncope (56.5%), arrhythmogenic onset of syncope (6.0%), nonsyncopal origin of TLC (1.4%), single episode during lifetime (2.1%). Reasons for TLC remained unidentified in 34% cases. 27 persons (6.5%) reported a family history of sudden death, mainly patients with presumably arrhythmogenic origin (24%). CONCLUSION: Our findings suggest that the overall prevalence of TLC in individuals aged 20-69 years is high. The most common cause of TLC is neurally-mediated syncope. These data about the epidemiology can help to develop cost-effective management approaches to TLC.

[The combined rehabilitative treatment of the children with obesity and metabolic syndrome].

The present study included a total of 66 children at the age from 11 to 16 years with obesity and metabolic syndrome. The latter condition in the childhood and adolescence is characterized by the pronounced disturbances of basal metabolism, vasoactive systems, psychoemotional status, and regulatory hormonal functions that determine the choice of rehabilitative modalities. The combined treatment of such disturbances is considered to be an efficacious method for the rehabilitation of these patients. It is recommended that cortexin be prescribed to the children presenting with obesity and metabolic syndrome because this medication promotes correction of the hormonal and metabolic status and improves the brain cognitive function.

[Peculiar features of the clinical and metabolic status and its variations under the influence of rehabilitative treatment in the children with obesity and diffuse non-toxic goiter].

A total of 120 children at the age of 10-15 years presenting with class I-II obesity were available for observation. Fifty two of them suffered diffuse non-toxic goiter. The combination of obesity and diffuse non-toxic goiter was associated with excessive body weight, insulin resistance, disturbances of lipid metabolism, and impaired tolerance of physical exercises. Differential therapeutic complexes have been proposed for the treatment of the children with diffuse nontoxic goiter. Their application was shown to induce positive dynamics of clinical conditions and laboratory characteristics of the patients.

[DNA sequence-specific ligands: XIV. Synthesis of fluorescent biologicaly active dimeric bisbenzimidazoles-DB(3, 4, 5, 7, 11)].

Five fluorescent symmetric dimeric bisbenzimidazoles DB(n) have been synthesized containing four 2,6-substited benzimidazole fragments and differ in length of oligomethylene linker (n=3, 4, 5, 7, 11) between the two bisbenzimidazole blocks. The ability of these dimeric bisbenzimidazoles to form complexes with double-stranded DNA (dsDNA) was shown by spectral methods. Upon binding to dsDNA DB(n) are localized in the minor groove. The DNA-methyltransferase Dnmt3a inhibition data are demonstrate the site-specific binding of dimeric bisbenzimidazoles DB(3) and DB(11) with oligonucleotide duplex.

An atomic force microscopy study in the detection of hepatitis B surface antigen by enzyme-linked immunosorbent assay.

Atomic force microscopy (AFM) was employed to study certain enzyme immunoassay steps for the detection of hepatitis B surface antigen (HBsAg). Physical adsorption of monoclonal antibodies (mAb), blocking of surface active sites free of antibodies by neutral proteins, and capture of HBsAg particles by sensitized surfaces were visualized successively in microplate wells of standard immunological plates from various manufacturers. The previously undescribed details such as "etching holes" up to 20 nm in depth were observed on the surface of plates some companies. The quantitative relationships between the optical density (OD) values obtained by enzyme immunoassay (EIA) and the number of antigen-antibody complexes in AFM were calculated.

Dimeric bisbenzimidazoles inhibit the DNA methylation catalyzed by the murine Dnmt3a catalytic domain.

When located in the DNA minor groove, dimeric bisbenzimidazoles DB(n) effectively inhibited in vitro the Dnmt3a catalytic domain (IC50 5-77 µM). The lowest IC50 value was observed for compound DB(11) with an 11-unit methylene linker joining the bisbenzimidazole fragments. Increased time of incubation of DNA with DB(n) as well as the presence of AT-clusters in DNA enhances the inhibitory effect.

Inhibition of murine DNA methyltransferase Dnmt3a by DNA duplexes containing pyrimidine-2(1H)-one.

Here we studied the inhibition of the catalytic domain of Dnmt3a methyltransferase (Dnmt3a-CD) by DNA duplexes containing the mechanism-based inhibitor pyrimidine-2(1H)-one (P) instead of the target cytosine. It has been shown that conjugates of Dnmt3a-CD with P-DNA (DNA containing pyrimidine-2(1H)-one) are not stable to heating at 65°C in 0.1% SDS. The yield of covalent intermediate increases in the presence of the regulatory factor Dnmt3L. The importance of the DNA minor groove for covalent intermediate formation during the methylation reaction catalyzed by Dnmt3a-CD has been revealed. P-DNA was shown to inhibit Dnmt3a-CD; the IC(50) is 830 nM. The competitive mechanism of inhibition of Dnmt3a-CD by P-DNA has been elucidated. It is suggested that therapeutic effect of zebularine could be achieved by inhibition of not only Dnmt1 but also Dnmt3a.

[A chronobiological approach to the treatment of obesity in children based at a sanatorium and spa facility].

The objective of the study was to evaluate results of non-medicamental treatment of 167 children with obesity taking into account dynamics of annual rhythms of their clinical, hormonal, metabolic, and psychological characteristics. The period from August till November was shown to be especially favourable in terms of body weight loss, improvement of hormonal, metabolic, and psychic status. Analysis of these changes permitted to correct the proposed mode of combined therapy of obesity during the period from December till July.

Proteome analysis of chloroplasts from the moss Physcomitrella patens (Hedw.) B.S.G.

Intact chloroplasts were prepared from protoplasts of the moss Physcomitrella patens according to an especially developed method. They were additionally separated into stroma and thylakoid fractions. The proteomes of intact plastids, stroma, and thylakoids were analyzed by 1D-electrophoresis under denaturing conditions followed by protein digestion and nano-LC-ESI-MS/MS of tryptic peptides from gel bands. A total of 624 unique proteins were identified, 434 of which were annotated as chloroplast resident proteins. The majority of proteins belonged to a photosynthetic group (21.3%) and to the group of proteins implicated in protein degradation, posttranslational modification, folding, and import (20.6%). Among proteins assigned to chloroplasts, the following groups are prominent combining proteins implicated in metabolism of: amino acids (6.9%), nucleotides (2.5%), lipids (2.2%), carbohydrates (2.4%), hormones (1.5%), isoprenoids (1.25%), vitamins and cofactors (1%), sulfur (1.25%), and nitrogen (1%); as well as proteins involved in the pentose-phosphate cycle (1.75%), tetrapyrrole synthesis (3.7%), and redox processes (3.6%). The data can be used in physiological and photobiological studies as well as in further studies of P. patens chloroplast proteome including structural and functional specifics of plant protein localization in organelles.

Inhibition of C5-cytosine-DNA-methyltransferases.

Changes in the methylation pattern of genomic DNA, particularly hypermethylation of tumor suppressor genes, occur at early stages of tumor development. Errors in DNA methylation contribute to both initiation and progression of various cancers. This stimulates significant interest in searching for inhibitors of C5-DNA-methyltransferases (MTases). Here we review the known nucleoside mechanism-based reversible and irreversible inhibitors of the MTases, as well as non-nucleoside ones, and discuss their inhibitory mechanisms and application for MTase investigations and cancer therapy.

[Hepatitis B markers in southern Altai inhabitants of the village of Mendur-Sokkon (the Republic of Altai). HBsAg subtyping in hepatitis B virus isolates with monoclonal antibodies]. / Markery virusnogo gepatita B u iuzhnykh altaitsev pos. Mendur-Sokkon (respublika Altai). Subtipirovanie HBsAg izoliatov BGB s pomoshch'iu monoklonal'nykh antitel.

Blood samples taken from 231 native inhabitants of the village of Mendur-Sokkon located in the Republic of Altai (South-Western Siberia, Russia) were tested for the presence of virus hepatitis B (HBV) markers. 31 samples (13.4%) were found to contain HBsAg, 111 samples (48.05%) were found to contain total anti-HBc antibodies, 123 samples (53.24%) were found to contain anti-HBs antibodies and 15 blood samples (6.49%), anti-HBc antibodies without anti-HBs antibodies and HBsAg. The age-dependent distribution of the occurrence of HBV markers among the aboriginal population of the South Altal remained unchanged (69.9 +/- 7.9%) for the last 50 years. The vertical and horizontal routes of HBV transmissions were noted. The data obtained in this study are indicative of a highly endemic character of HBV of the territory of Mendur-Sokkon. HBsAg-positive blood samples were taken for HBsAg subtyping with the use of a panel of monoclonal antibodies. Two subtypes of HBsAg were detected: ayw1-2 and ayw3varB with the occurrence of 92.6% and 7.4%, i.e. distributed in the ratio 25/2.

Study of the mechanism of action of p-chloromercuribenzoate on endonuclease from the bacterium Serratia marcescens.

The mechanism of action of p-chloromercuribenzoate (PCMB) on Serratia marcescens nuclease was investigated. The analysis showed that PCMB forms complexes with DNA. Binding of C7H5O2Hg+ to DNA changes the secondary structure of the DNA. These changes alter the enzymatic activity of S. marcescens nuclease, which was previously found to be sensitive to the secondary structure of the substrates. The nuclease activity was either suppressed or stimulated in the presence of PCMB depending on the C7H5O2Hg+ to nucleotide equivalent ratio. Binding of C7H5O2Hg+ to DNA did not form an abortive enzyme-substrate complex. Binding of Mg2+ to the C7H5O2Hg-DNA complex caused appropriate changes in secondary structure of the substrate. Since Mg2+ and C7H5O2Hg+, though differing in the type of metal cation, are similar in their mechanisms of influence on enzymatic activity of S. marcescens nuclease, the identity of other metal-containing effectors in their mechanism of action on Serratia marcescens nuclease is assumed.

[Effect of linker length on the photomodification process of tyrosine residues in N-(tyrosyl)-N'-(5-azido-2-nitrobenzoyl)diaminoalkanes]. / Vliianie dliny linkera na protsess fotomodifikatsii ostatka tirozina v N-(tirozil)-N'-(5-azido-2-nitrobenzoil)diaminoalkanakh.

N-(Tyrosyl)-N'-(5-azido-2-nitrobenzoyl)-1,4-diaminobutane, containing a Tyr residue connected with the photoreactive aryl azide group through the diaminobutylene linker, was synthesized as a model for studying the photomodification of Tyr residues in proteins. This compound and the compound with a shorter, 1,2-diaminoethylene linker, obtained previously, were subjected to computer modeling to find their minimal-energy conformations. The aromatic rings of Tyr and 5-azido-2-nitrobenzoic acid residues in the latter compound were localized in parallel planes at a distance of approximately 0.3 nm between them and were shown to be implicated in stacking interactions. On the contrary, the planes of aromatic rings of the former compound with a longer, diaminobutylene linker were found to be situated perpendicularly to each other, with the distance between the centers of the rings being approximately 0.6 nm. The computer analysis was confirmed by experimental results: when studying the photomodification of the compound with the diaminobutylene linker, neither stable products of the Tyr photomodification nor unstable products capable of transformation into stable products in the dark were found. On the contrary, such products were previously identified in the case of the compound with diaminoethylene linker. The formation of amino, nitro, azoxy, and azo derivatives was common for the photomodification of both compounds.

[Electron microscopic study of the combined action of ampicillin and cephalexin on E. coli]. / Elektronno-mikroskopicheskoe izuchenie kombinirovannogo deistviia ampitsillina i tsefaleksina na E. coli.

The data of electron microscopy study of morphological variation of E. coli, strain 423 in the logarithmic phase after exposure to ampicillin (2 gamma/ml) and cephalexin (4 gamma/ml) are presented. Pronounced ultrastructural changes not only in the cell wall but also in the cytoplasm were found. After exposure to ampicillin alone changes of the same type were observed. However, after exposure to the combination of the 2 antibiotics these changes were more pronounced and observed in the predominating part of the cells. Examination of ultrathin slices of the strain treated with cephalexin revealed no ultrastructural changes. The morphological changes in the cells of E. coli, strain 423 after its treatment with ampicillin and cephalexin combination were due mainly to ampicillin effect, while cephalexin increased the level of the changes.