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1.
Angiol Sosud Khir ; 26(2): 76-83, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32597887

RESUMO

The transradial access has deservedly become the 'gold standard' while performing various X-ray endovascular interventions both diagnostic and therapeutic ones. However, along with all its advantages, it is not without disadvantages. These difficulties for the most part are related to peculiarities of the anatomy of upper-limb arteries. It is exactly complex anatomy that is the most common cause of complications and compelled change of the access while using the right radial artery. The purpose of our study was to examine the symmetry of complex anatomy of upper-limb arteries in order to choose an optimal and safe way of conversion of the access in case of forced refusal from the right radial access. For this reason there was developed an open multicentre registry acronymized as COMPAAS (COMPlex Anatomy of Arteries and Symmetry). During the work of this Registry from February to December 2018, correspondents of the study became 35 colleagues from 23 clinics of 11 cities of Russia. The working group analysed a total of 127 patients presenting with 157 variants of complex anatomy of lower limb arteries: high bifurcation of the radial artery (84), complete loop or tortuosity (66), and compartmental calcification of brachial arteries (7). The anatomy of arteries on the opposite upper extremity was studied based on angiographic findings. The most frequent variant (84 cases) of complex anatomy was high bifurcation of the radial artery at the level of the a. brachialis (20.9% of cases), with the origin of the brachial artery at the level of the a. axillaris being revealed half as often (9.9%). The maximum percentage of symmetry was observed in the group of patients presenting with compartmental calcification of upper-limb arteries (85.7%). Complete loop or marked (more than 100°) tortuosity of arteries on both arms was revealed in 54% of cases. Besides, in 25% of cases, tortuosity was combined with the high origin of the radial artery. It is noteworthy that none of the 127 patients appeared to have complex anatomy on the a. ulnaris. When revealing pronounced calcification of arteries of the forearm or a combination of high bifurcation with tortuosity, it seems feasible to decide upon conversion of the access to the femoral one (a. femoralis) or ulnar (a. ulnaris). In isolated high bifurcation on the right, effective conversion to the contralateral (left) radial approach is possible in not less than 75% of cases.


Assuntos
Angiografia , Artéria Radial/cirurgia , Humanos , Radiografia , Federação Russa , Extremidade Superior
2.
Dokl Biochem Biophys ; 479(1): 118-122, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29779113

RESUMO

The patterns of formation of RNA nanoparticles (NPs) during thermal cycling of bacterial total tRNA in the presence of cations Ca2+, Mn2+, Ni2+, Zn2+, Co2+, and Cu2+ were studied. The optimal conditions for the production of NPs were found, and it was revealed that their size depends on the ratio of the concentrations of Me2+ and tRNA. The concentration of reagents for obtaining NPs of small size (from 5 to 100 nm) was selected. It was shown that tRNA-based nanoparticles can comprise short (20-50 nt) ribooligonucleotides, including aptamers and siRNAs. The stability of NPs during storage in buffer solutions of various composition was studied. It was found that the initial suspensions of NPs are quite stable, but they are rapidly destroyed in PBS buffer (pH 7.4). A simple and effective stabilizer (polyarginine) was found, the additives of which ensure the preservation of nanoparticles in PBS buffer for more than 5 h. Nanoparticles modified with the stabilizer are resistant to blood serum nucleases and can be used for transfection.


Assuntos
Cátions Bivalentes/química , Nanopartículas/química , RNA de Transferência/química , Tamanho da Partícula
3.
Dokl Biochem Biophys ; 463: 259-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26335826

RESUMO

This work is devoted to studying the mechanisms of formation of DNA-containing microparticles (MPs) during PCR. It was found that pyrophosphate, a byproduct of DNA synthesis, and magnesium cations are required for their formation, as evidenced by the results of biochemical and electron microscopy studies.


Assuntos
DNA/química , DNA/metabolismo , Difosfatos/metabolismo , Compostos de Magnésio/metabolismo , Microesferas , Reação em Cadeia da Polimerase , DNA/genética , Difosfatos/farmacologia , Cloreto de Magnésio/farmacologia , Compostos de Magnésio/farmacologia
4.
Ultrasonics ; 62: 156-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26049732

RESUMO

Ultrasonic acoustic waves propagating in thin piezoelectric plates with free faces are used for bacteria detection in micro-litre liquid samples deposited on one of the plate surface. The limits of the detection at normal conditions are as low as 0.04% for highly diluted rich cultural Luria-Bertani broth (LB-media) in distillate water, 0.07% for bacterial cells in distillate water, and 0.6% for bacterial cells in LB-media. For all analytes the most probable detection mechanism is the change in liquid conductivity. Because of no using any sorbent film the long-term stability of the detection is expected as very high.


Assuntos
Acústica/instrumentação , Técnicas Biossensoriais/instrumentação , Mycobacterium smegmatis , Pseudomonas aeruginosa , Desenho de Equipamento , Manufaturas , Som
5.
Mikrobiologiia ; 84(6): 645-59, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26964354

RESUMO

Survival of bacterial populations treated with lethal doses of antibiotics is ensured by the presence of very small numbers of persister cells. Unlike antibiotic-resistant cells, antibiotic tolerance of persisters is not inheritable and reversible. The present work provides evidence supporting the hypothesis of transformation (maturation) of persisters of an opportunistic pathogen Pseudomonas aeruginosa revealed by ciprofloxacin (CF) treatment (25-100 µg/mL) into dormant cystlike cells (CLC) and non-culturable cells (NC), as was described previously for a number. of non-spore-forming bacteria. Subpopulations of type 1 and type 2 persisters, which survived antibiotic treatment and developed into dormant forms, were heterogeneous in their capacity to form colonies or microcolonies upon germination, in resistance to heating at 70 degrees C, and in cell morphology Type 1 persisters, which were formed after 1-month incubation in the stationary-phase cultures in the medium with decreased C and N concentrations, developed in several types of surviving cells, including those similar to CLC in cell morphology. In the course of 1-month incubation of type 2 persisters, which were formed in exponentially growing cultures, other types of surviving cells developed: immature CLC and L-forms. Unlike P. aeruginosa CLC formed in the control post-stationary phase cultures without antibiotic treatment, most of 1-month persisters, especially type 2 ones, were characterized by the loss of colony-forming capacity, probably due to transition into an uncultured state with relatively high numbers of live intact cells (Live/Dead test). Another survival strategy of P. aeruginosa populations was ensured by a minor subpopulation of CF-tolerant and CF-resistant cells able to grow in the form of microcolonies or regular colonies of decreased size in the presence of the antibiotic. The described P. aeruginosa dormant forms may be responsible for persistent forms in bacteria carriers and latent infections and, together with antibiotic-resistant cells, are important as components of test systems to assay the of efficiency of potential pharmaceuticals against resistant infections.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Pseudomonas aeruginosa/ultraestrutura
6.
Mikrobiologiia ; 83(2): 225-35, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25423726

RESUMO

Electron microscopic investigation of four samples of ancient ice wedge from the Pleistocene glacial complex of Mamontova Gora (Yakutiya, Russia) revealed high diversity of bacteriomorphic particles. Their structural features included the presence of electron-transparent zones, presumably inclusions containing storage compounds, and microenvironment (capsules or external sheaths). These features may be a result of adaptive strategies providing for microbial survival under permafrost conditions. Predominance of rod-shaped forms morphologically resembling coryneform actinobacteria was found. X-ray microanalysis revealed organic origin of bacteriomorphic particles. Some particles were characterized by incomplete spectra of the major biogenic elements, resulting probably from low-temperature damage to the cellular structures. Total numbers of aerobic heterotrophic bacteria determined by plating on nutrient media were comparable to the values obtained for permafrost soils and Arctic ice. Predominance of coryneform actinobacteria was observed. Abundance of these evolutionarily early groups of actinobacteria may indicate the ancient origin of the microflora of the relic frozen rocks.


Assuntos
Bactérias Aeróbias/isolamento & purificação , Camada de Gelo/microbiologia , Actinomycetales/isolamento & purificação , Regiões Árticas , Biodiversidade , Microanálise por Sonda Eletrônica , Gelo , Federação Russa
8.
Mikrobiologiia ; 82(6): 660-71, 2013.
Artigo em Russo | MEDLINE | ID: mdl-25509404

RESUMO

Antimony leaching from sulfide ore samples by an experimental consortium of thermoacidophilic microorganisms, including Sulfobacillus, Leptospirillum, and Ferroplasma strains was studied. The ores differed significantly in the content of the major metal sulfides (%): Sb(S), 0.84 to 29.95; Fe(S), 0.47 to 2.5, and As(S), 0.01 to 0.4. Independent on the Sb(S) concentration in the experimental sample, after adaptation to a specific ore and pulp compaction the microorganisms grew actively and leached/oxidized all gold-antimony ores at 39 ± 1 degrees C. The lower was the content of iron and arsenic sulfides, the higher was antimony leaching. For the first time the investigations conducted with the use of X-ray microanalysis research made it possible to conclude that in a natural high-antimony ore Sb inhibits growth of only a part of the cell population and that Ca, Fe, and Sb may compete for the binding centers of the cell.


Assuntos
Antimônio/metabolismo , Bactérias/metabolismo , Ouro/metabolismo , Consórcios Microbianos/fisiologia , Antimônio/química , Bactérias/ultraestrutura , Ouro/química , Oxirredução
9.
Mikrobiologiia ; 82(6): 715-22, 2013.
Artigo em Russo | MEDLINE | ID: mdl-25509410

RESUMO

Molecular identification of the filterable forms of microorganisms in the water of the Rybinsk reservoir, one of the largest open water bodies in European Russia, was carried out. The number of ultrasmall microbial cells passing through 0.22 µm filters was 10(4) cells/mL. These were represented by both bacteria and archaea. Most bacterial 16S rRNA gene sequences retrieved from filtered water belonged to the Betaproteobacteria and exhibited high similarity (99.0-99.5%) to thos of bacteria of the genus Polynucleobacter. The archaeal 16S rRNA gene clone library was composed of the sequences of members of the Euryarchaeota, including the orders Methanobacteriales and Methanomicrobiales, as well as of two archaeal groups (LDS and RC-V) with no characterized representatives. The species composition of filterable bacteria from reservoir water wast different from that revealed previously in bogs and small lakes at catchment areas; The pool of filterable archaea in the reservoir exhibited, however, significant similarity to that for boggy catchment areas and was characterized by perdominance of the clade LDS. Available data indicate that this archaeal group is typical of the northern freshwater ecosystems, and the organisms of this group are represented by ultrasmall cells.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Água Doce/microbiologia , Microbiologia da Água , Bactérias/isolamento & purificação , Federação Russa
13.
Prikl Biokhim Mikrobiol ; 45(2): 181-7, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19382705

RESUMO

The effect of hexylresorcinol (HR), a chemical analogue of microbial anabiosis autoinducers of the alkylhydroxybenzene (AHB) group, on the stability of biological membranes and monolamellar liposomes formed of egg phosphatidylcholine (ePC) was studied. According to spectrophotometry and electron microscopy studying of HR-loaded liposomes in the presence of a surface-active agent Tween 20, the critical ratio between HR and ePC for liposome preservation was found to be close to equimolar. The trends in HR influence on membrane structural organization and stability confirmed in experiments on liposomes were also reproduced on intact bacterial cells explaining non-species-specific effect of AHBs. The demonstrated high efficiency of AHB biocides may be used in material and equipment protection against biocorrosion.


Assuntos
Anti-Infecciosos/química , Bactérias/crescimento & desenvolvimento , Hexilresorcinol/química , Lipossomas Unilamelares/química , Leveduras/crescimento & desenvolvimento , Anti-Infecciosos/farmacologia , Hexilresorcinol/farmacologia , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacologia , Polissorbatos/química , Polissorbatos/farmacologia , Tensoativos/química , Tensoativos/farmacologia , Lipossomas Unilamelares/farmacologia
15.
Mikrobiologiia ; 71(1): 37-48, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11910805

RESUMO

X-ray microanalysis showed that vegetative cells, viable resting forms, and nonviable forms (micromummies) of the bacteria Bacillus cereus and Micrococcus luteus and the yeast Saccharomyces cerevisiae differ in the contents of bioelements S, P, Ca, and K and the Ca/K and P/S ratios. Viable resting forms (cystlike refractory cells and bacillar endospores) had more calcium and less phosphorus and potassium than vegetative cells, the difference being higher for bacilli than for micrococci and yeasts. The distinctive feature of all viable resting microbial forms was their low P/S ratios and high Ca/K ratios. The differences revealed in the cellular content and ratios of bioelements probably reflect changes in ionic homeostasis accompanying the transition of vegetative microbial cells to the dormant state. Relevant potassium parameters indicate that the membranes of viable resting forms retain their barrier function. At the same time, the nonviable forms, even morphologically intact, of B. cereus and S. cerevisiae exhibited an anomalously low content of potassium, while those of M. luteus had an anomalously high content of this element. This suggests that the cellular membranes of micromummies lose their barrier function, which results in a free diffusion of potassium ions across the membranes. The possibility of using the elemental composition parameters for quick analysis of the physiological state of microorganisms in natural environments is discussed.


Assuntos
Bacillus cereus/química , Micrococcus luteus/química , Saccharomyces cerevisiae/química , Bacillus cereus/fisiologia , Cálcio/análise , Microanálise por Sonda Eletrônica , Homeostase , Micrococcus luteus/fisiologia , Fósforo/análise , Potássio/análise , Saccharomyces cerevisiae/fisiologia , Enxofre/análise
16.
Mikrobiologiia ; 71(1): 30-6, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11910804

RESUMO

The contents of several chemical elements were assessed in the haloalkaliphilic acetogenic bacterium Natroniella acetigena and the alkaliphilic sulfate-reducing bacterium Desulfonatronum lacustre using X-ray microanalysis, stereoscanning microscopy, and mass spectrometry. The organisms were found to differ significantly in their relative contents of S, K, P, and Cl. The P/S ratio in cells of the alkaliphilic bacteria studied grown on mineral media at different pH was pH-dependent. With a pH increase from 9 to 10, potassium extrusion from cells was observed, suggesting that secondary K+/H+ antiport activity accounts for the homeostasis of cytosolic pH. Deenergization of bacterial cells in the presence of inhibitors and ionophores results in specific changes in the P/S ratio, which may be considered an indicator of the cell energetic state. In Natroniella acetigena, the content of intracellular Cl was directly proportional to the NaCl concentration in the medium. Some metals were shown to be necessary for the N. acetigena viability; the requirement for Ni and Co was absolute. Although little demand for Mg was characteristic of the bacteria studied, their growth was stimulated by an increase in Mg concentration, and the cell resistance to lysis was enhanced.


Assuntos
Bactérias Anaeróbias/química , Álcalis , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Bacteriólise , Cloro/análise , Cobalto , Meios de Cultura , Microanálise por Sonda Eletrônica , Concentração de Íons de Hidrogênio , Magnésio , Espectrometria de Massas , Níquel , Fósforo/análise , Potássio/análise , Cloreto de Sódio , Sulfatos/metabolismo , Enxofre/análise
17.
Mikrobiologiia ; 71(6): 836-48, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12526207

RESUMO

The paper deals with the X-ray microanalysis of the elemental composition of bacteriomorphic particles in 170,000-year old Antarctic permafrost sediments and in indoor dust. A comparative analysis of the phosphorus, sulfur, calcium, and potassium contents and the Ca/K and P/S ratios in these particles and in reference microbial cells occurring in different physiological states showed that the absence of P and/or S peaks in the X-ray spectrum of an object may indicate that it is abiotic. Resting microbial forms can be revealed on the basis of the following characteristic features: an increased content of Ca, a high Ca/K ratio, and a low P/S ratio. Model experiments with nonviable bacterial and yeast micromummies with alterations in the structural and barrier functions of the cytoplasmic membrane showed that micromummies can be recognized by a super-high content of a marker element (e.g., P, K, or Si), accumulated due to facilitated diffusion along the deliberately created concentration gradient. Such an analysis of the permafrost sediment and dust made it possible to suggest the presence of mummified cells in these objects. The possibility of using X-ray microanalysis for the detection of microbial cells in natural habitats in order to enhance the efficiency of ecological monitoring of the environment is discussed.


Assuntos
Bactérias/isolamento & purificação , Microbiologia Ambiental , Sedimentos Geológicos/microbiologia , Leveduras/isolamento & purificação , Regiões Antárticas , Bactérias/química , Fenômenos Fisiológicos Bacterianos , Cálcio/análise , Poeira/análise , Ecologia , Microanálise por Sonda Eletrônica , Sedimentos Geológicos/química , Técnicas Microbiológicas/métodos , Fósforo/análise , Potássio/análise , Enxofre/análise , Leveduras/química , Leveduras/fisiologia
18.
Prikl Biokhim Mikrobiol ; 34(2): 180-2, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9567294

RESUMO

The elemental compositions of cells of representatives of five bacterial genera (Hyphomonas vulgare NP-160, Caulobacter bacteroides NP-105, Flectobacillus major Mm, Escherichia coli, and Spirulina platensis) was studied by electron microscopic x-ray microanalysis. The contents of P, S, Cl, K, and Ca were determined. The bacterial species studied in this work substantially differ by the contents of these elements. A high content of K is typical of S. platensis, whereas F. major, an aquatic form, is rich in Cl. The other bacterial species were had the levels of K, Ca, and the K/Ca index, which correlated with the stability of their cell membranes and resistance to stress. In E. coli, the spectrum of the elemental composition and the values of P/S and K/Ca are indicative of high energy potential and low tolerance of membranes.


Assuntos
Bactérias/química , Elementos Químicos , Bactérias/classificação , Filogenia
19.
Mikrobiologiia ; 62(6): 1064-71, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8114644

RESUMO

The resistance against ionizing radiation of seven cultures of oligotrophic and eutrophic bacteria was investigated in the interval 0-360 Gr/h. It is determine that all of tested bacteria are distributed into three groups according to the lever of their resistance. Most resistant were: Methylobacterium organophilum, Pedodermatophilus halotolerans (LD50 = 270 Cr/h). These organisms are close to Deinococcus radiodurans in the survival. Middle resistance shown water-born ring-forming bacteria Flectobacillus major, Arcocella aquatica (LD50 = 173 and 210 Gr/h respectively). High sensitive were eutrophs: Pseudomonas fluorescens, Escherichia coli (LD50 = 43 and 38 Gr/h respectively). By use of X-ray microanalysis was shown that after the radiation potassium content in cell was increased and calcium content was decreased. The elements content in the cells of eutrophs (Escherichia coli) remains without change. In present paper are also discussed possible mechanisms of the resistance of oligotrophs against gamma-irradiation.


Assuntos
Bactérias/efeitos da radiação , Tolerância a Radiação , Bactérias/química , Cálcio/análise , Magnésio/análise , Potássio/análise
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