[Clinical manifestations of Legionella pneumonia in hematology patients].

Aim: To detect the most common clinical manifestations of Legionella pneumonia (LP) in immunocompromized patients.

Subjects And Methods: Clinical manifestations, the results of investigation of bronchoalveolar lavage fluid (BALF) and urine, and the data of lung computed tomography (CT) were studied in patients with blood system diseases and acute respiratory failure (ARF).

Results: The diagnosis of LP was verified in 8 (10.

Optical investigation of the natural electron doping in thin MoS2 films deposited on dielectric substrates.

Two-dimensional (2D) compounds provide unique building blocks for novel layered devices and hybrid photonic structures. However, large surface-to-volume ratio in thin films enhances the significance of surface interactions and charging effects requiring new understanding. Here we use micro-photoluminescence (PL) and ultrasonic force microscopy to explore the influence of the dielectric environment on optical properties of a few monolayer MoS2 films.

[Features of legionella biofilm formation in artificial and natural water systems].

Aim: Study the ability to form monospecies and associative biofilms as a characteristic oflegionella strains and features of organization of natural legionella biofilms in potentially dangerous water systems.

Materials And Methods: Comparative evaluation ofthe ability of 28 strains of Legionella spp. to form biofilms was determined in water according to previously developed procedure.

[Prevalence of glucosyl transferase Lgt among Legionella pneumophila strains isolated from various sources].

Aim: Determine various members of Lgt glucosyl transferase family among microorganisms of Legionellaceae genus from museum collection and legionellae strains recently isolated in the Russian Federation and Germany.

Materials And Methods: Presence of 3 types of glucosyl transferase were determined in 73 strains of L. pneumophila and Legionella spp.

[Examination of the contamination aetiological agent of legionellosis in the water supply systems of medical treatment facilities].

This study considers the features of colonization of water distribution systems by Legionella in large multi-type health-care facilities in Moscow-city, Russia. The investigation of 16 pavilions in 5 multi-type health-care facilities had found the hith level of hot water systems contaminated by Legionella pneumophila (68%), including the risk units. Among the different species of Legionella pneumophila, circulating in hot water systems of health-care facilities, the following strains had prevailed: the serogroup 6 (44%), 5 (26%) and 1 (13%).

[Serologic characteristic of Legionella pneumophila strains isolated from potentially dangerous water systems in Russian Federation in 2007 - 2011].

Aim: Study serologic diversity of Legionella pneumophila strains circulating in potentially dangerous water systems in Russian Federation by using an international panel of monoclonal antibodies.

Materials And Methods: Serotyping of 234 L. pneumophila strains isolated from coolers of industrial facilities and systems of hot water supply in Russian Federation in 2007 - 2011 was performed by enzyme immunoassay by using an international panel of monoclonal antibodies.

[A case of legionellesis pneumonia verified by isolation of Legionella pneumophila serogroup 1 from bronchoalveolar lavage fluid treated with levofloxacine and tigecycline].

A male patient received non-chemotherapeutic drugs which induced deep neutropenia complicated with sepsis, bilateral pneumonia, acute respiratory insufficiency. Artificial pulmonary ventilation was applied. The examination of bronchoalveolar lavage showed the presence of the culture L.

[Rate and level of contamination of potentially dangerous water supply facilities in Moscow region by Legionella pneumophila].

Aim: To assess rate and level of contamination by Legionella pneumophila of cooling water systems in industrial facilities as well as hot water supply systems of administrative buildings in Moscow region.

Materials And Methods: Cooling water systems of 8 industrial facilities and hot water supply systems of 12 administrative buildings or complexes located in Moscow or Moscow region were examined. Samples of water, washes and biofilms were studied by bacteriologic methods and RT-PCR.

[Methodic bases for providing the population and potentially dangerous water objects with biosafety against the pathogens of Legionellosis].

The paper considers the key aspects of the ecology of Legionella determining the increasing role of the pathogen in the emergence of human infectious diseases in postinduatrial society. Formation of Legionella biofilms on potentially dangerous water objects with possible further aerosol or aspiration transmission of the pathogen may lead to large epidemic outbreaks and sporadic cases of the infection. Based on international experience and the results of their studies, the authors propose a current legionellosis prevention concept based on microbiological monitoring and control of potentially dangerous water objects.

[Analysis of prevalence and variability of Legionella pneumophila and Legionella spp. strains on the basis of study of allelic profiles].

Aim: To analyze prevalence and variability of Legionella strains isolated in town Verkhnaya Pyshma located in Sverdlovsk region during prophylactic surveillance of potentially dangerous water objects in 2007 - 2008.

Materials And Methods: Sequencing of mip gene was conducted for identification of species of Legionella. Multi-locus sequence typing was used for describing of allelic profiles of Legionella pneumophila strains.

[Modern conception of organization of epidemiological surveillance for Legionella infections].

Evolution of views on legionellosis is analyzed in the review: from extremely dangerous rare infection to sufficiently widespread severe pneumonia emergence of which is determined by features of ecology and prevalence of natural water microorganism in potentially dangerous water systems created by man. Epidemiologic features of 3 main groups of legionellosis determined according to place of acquisition are discussed: sporadic (community-acquired) legionellosis; nosocomial legionellosis; legionellosis related with trip or travel. Modern principles of organization of epidemiologic surveillance for legionellosis based on the disease's incidence monitoring, observation on circulation of the agent in potentially dangerous water systems, conducting of prophylactic measures aimed at prevention of sporadic cases and epidemic outbreaks.

[Using real-time polymerase chain reaction for detection of Legionella in objects of the environment].

Aim: To assess efficacy of using the method of quantitative detection of Legionella in objects of the environment by real-time polymerase chain reaction (RT-PCR).

Materials And Methods: For the development of the assay, genus-specific primers from gene coding 16S rRNAas well as species-specific primers for detection of Legionella pneumophila on the basis of mip gene sequence. For quantitative detection of L.

[Assessment of bactericidal activity of disinfectants against Legionella on the biofilm model].

Comparative assessment of bactericidal activity of different disinfectants against Legionella biofilms was conducted. Monospecies biofilms of 3 strains of Legionella pneumophila obtained on plastic plates in stable conditions were used as models. It has been shown that for degradation of biofilms as well as for prophylactic action of disinfectants in preventing formation of biofilms on plastic surfaces, higher concentrations of preparations were needed as compared to their bactericidal concentrations for culture of Legionella determined by method of serial dilutions.

[Development and use of the assay for Legionella pneumophila detection based on fluorescent real-time/endpoint polymerase-chain reaction].

The aim of the work was to develop a PCR-based assay for detection of L. pneumophila and L. micdadei in environmental samples as well as in clinical samples from low respiratory tract and to assess its analytic characteristics.

[Application of molecular genetic methods during Legionnaires' disease outbreak in town Verkhnyaya Pyshma].

The aim of the study was to perform molecular genetic analysis based on multi-locus sequence typing in order to identify source of Legionnaires' disease outbreak in town Verkhnyaya Pyshma in July 2007 and genetic profile of the causative agent. Sequence-based typing protocol recommended by European Working Group on Legionella infection (EWGLI) was used. It was not possible to obtain satisfactory results of Fla gene sequencing for all samples.

[Standards for laboratory diagnostics of legionellosis and their application during epidemic outbreak of pneumonia in town Verkhnyaya Pyshma].

High effectiveness of application of international standards for legionellosis laboratory diagnostics was confirmed during investigation of pneumonia outbreak in town Verkhnyaya Pyshma. Use of immunochromatographic method and enzyme immunoassay for detection of Legionella antigen in urine of patients allows to confirm diagnosis of Legionella infection during several hours, promptly begin etiologic antibacterial treatment and reveal possible sources of infection in potentially dangerous environmental objects.

[Legionella natural biofilms and their role in epidemiology of the infection: methods of study and modelling].

Ability of Legionella species to form biofilms in association with other microorganisms is the key factor of their spreading in potentially dangerous water systems. Ability of different strains of Legionella to form monospecies biofilms as well as biofilms in association with Pseudomonas aeruginosa in constant conditions was analyzed. It was shown that ability of Legionella strains to form monospecies biofilms correlates with their ability to persist in biofilms formed by P.

[Epidemiologic examination of focuses of community-acquired pneumonia caused by Legionella].

Main directions of epidemiologic examination of community-acquired pneumonia focus caused by Legionella accounting for features of epidemic process of this infection are discussed. Typical questionnaires, suggested list of documents, characteristics of laboratory tests are presented. Importance of epidemiologic examination of disease focuses as a basis for adequate sanitary and antiepidemic (prophylactic) measures for suppression of outbreaks of Legionella infection are underlined.

[Modern views on the epidemiology of legionellosis: operations procedure during epidemic outbreaks and preventive monitoring].

Key aspects of legionellosis epidemiology determining the rising role of Legionella in human infectious diseases in conditions of postindustrial community were discussed. It was shown that formation of Legionella biofilms on potentially dangerous water objects with possible further aerosol or aspiration transmission of microorganisms leads to major epidemic outbreaks and sporadic cases of infection. Main principles of actions during preventive monitoring of Legionella in the environment and epidemic outbreaks of legionellosis were described.

[Biofilm formation by Legionella spp. in experiment].

Ability of biofilm formation was studied in 28 strains belonging to 12 species of Legionella. Optimal conditions for formation of biofilms were ascertained using reference strain Legionella pneumophila Philadelphia 1. Comparative assessment of the ability of Legionella spp.

[Effect of the constitutive activity of pathogenicity genes in Listeria monocytogenes].

The effect of the constitutive expression of pathogenicity factors in L. monocytogenes was studied on the model of the intraperitoneal infection of mice. The constitutive expression was due to a single amino acid substitution in the transcriptional factor PfrA, the master regulator of L.

[Different species of Legionella plasmids and virulence].

Plasmids with a molecular weight of 2.5 to 80 MD were shown to be present in a significant portion of different-type Legionella strains including high-virulence isolates L. pneumophila, serogroup 1, and L.

[A new complex approaches for the identification of Listeria isolated during production of fermented sausages].

Distribution L. monocytogenes and other Listeria spp. in raw meat and during manufacturing of fermented meat products is investigated.

[The contribution of system regulation of pathogenicity-determining genes expression to the virulence of facultative intracellular parasites].

Bacteria which belong to the group of facultative parasites are capable of intensive proliferation both outside the organism and inside eukaryotic cells, thus often causing severe human and animal illness. The necessity of quick adaptation to the alteration of conditions after intrusion into the macro-organism gave rise to the development of complex genetic systems, regulating the activity of various gene groups. The review, written by the example of two pathogen bacteria, the gram-positive Listeria monocytogenes and the gram-negative Legionella pneumophila, illustrates up-to-date data that concern system regulation of genes, coding pathogenicity factors, as adaptive response of a bacterium to changes in outer conditions within the infectious process.

[Listeria pathogenicity factors and their role in pathogenesis and laboratory diagnosis of listeriosis].

The mechanisms of relationships between Listeria and eukaryotic cells on the level of the main biomolecules are analyzed. These mechanisms determine the penetration and multiplication of Listeria and their importance for the pathogenesis of listeriosis. The theoretical and practical aspects of the regulation of the expression of pathogenicity factors in Listeria, connected with the activation of the regulatory protein PrfA and autoregulatory mechanisms, are considered.