806 research outputs found

    Роль протеиназ крови и их ингибиторов в механизмах противовирусной защиты

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    Досліджено наявність трипсиноподібних протеїназ та їх інгібіторів у донорській крові людини, промислових відходах одержання гаммаглобуліну, комерційних вітчизняних препаратах (імуноглобулін, інтерферон, герпетична та туляремійна вакцини), у закордонних препаратах (протигрипозні вакцини — ''Інфлувак'', ''Ваксігрип'', ''Флюарікс'', вакцина проти гепатиту А — ''Аваксім''; препарати з крові — ''Фраксіпарин'' і ''Солкосерил''). З промислових відходів одержання гаммаглобуліну людини виділено ізоформу інгібітора трипсиноподібних протеїназ, що має захисну дію при зараженні експериментальних тварин смертельною дозою вірусу грипу A/PR/8/34 (А/Н1N1).The presence of the trypsin-like proteinases and their inhibitors in the blood of human donors, in industrial wastes of gamma-globulin, in commercial domestic preparations (immunoglobulin, interferon, vaccine for herpes and tularemia), in foreign preparations (anti-influenza vaccine — Influvac, Vaxigrір, Fluarix, vaccines for hepatitis A — Avaxim; preparations from blood — Fraxiparine, Solcoseryl) is studied. From the industrial wastes of the gamma-globulin production, an isoform of trypsin-like proteinases with protective activity at infection of experimental animals with a lethal dose of A/PR/8/34 (А/Н1N1) grippe is selected

    High genetic diversity ofVibrio choleraein the European lake Neusiedler See is associated with intensive recombination in the reed habitat and the long-distance transfer of strains

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    Coastal marine Vibrio cholerae populations usually exhibit high genetic diversity. To assess the genetic diversity of abundant V. cholerae non-O1/non-O139 populations in the Central European lake Neusiedler See, we performed a phylogenetic analysis based on recA, toxR, gyrB and pyrH loci sequenced for 472 strains. The strains were isolated from three ecologically different habitats in a lake that is a hot-spot of migrating birds and an important bathing water. We also analyzed 76 environmental and human V. cholerae non-O1/non-O139 isolates from Austria and other European countries and added sequences of seven genome-sequenced strains. Phylogenetic analysis showed that the lake supports a unique endemic diversity of V. cholerae that is particularly rich in the reed stand. Phylogenetic trees revealed that many V. cholerae isolates from European countries were genetically related to the strains present in the lake belonging to statistically supported monophyletic clades. We hypothesize that the observed phenomena can be explained by the high degree of genetic recombination that is particularly intensive in the reed stand, acting along with the long distance transfer of strains most probably via birds and/or humans. Thus, the Neusiedler See may serve as a bioreactor for the appearance of new strains with new (pathogenic) properties.The study was financed by the Austrian Science Fund FWF, project nr P21625-B20. In addition, CP and ISD were partially supported by the Austrian Science Fund FWF, P25745-B20. CA thanks to the Ministerio de Educacion, Cultura y Deporte and FEDER funds for the grant AGL2014-58933-P. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.Peer Reviewe

    Performance Characteristics of qPCR Assays Targeting Human- and Ruminant-Associated Bacteroidetes for Microbial Source Tracking across Sixteen Countries on Six Continents

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    Numerous quantitative PCR assays for microbial fecal source tracking (MST) have been developed and evaluated in recent years. Widespread application has been hindered by a lack of knowledge regarding the geographical stability and hence applicability of such methods beyond the regional level. This study assessed the performance of five previously reported quantitative PCR assays targeting human-, cattle-, or ruminant-associated Bacteroidetes populations on 280 human and animal fecal samples from 16 countries across six continents. The tested cattle-associated markers were shown to be ruminant-associated. The quantitative distributions of marker concentrations in target and nontarget samples proved to be essential for the assessment of assay performance and were used to establish a new metric for quantitative source-specificity. In general, this study demonstrates that stable target populations required for marker-based MST occur around the globe. Ruminant-associated marker concentrations were strongly correlated with total intestinal Bacteroidetes populations and with each other, indicating that the detected ruminant-associated populations seem to be part of the intestinal core microbiome of ruminants worldwide. Consequently tested ruminant-targeted assays appear to be suitable quantitative MST tools beyond the regional level while the targeted human-associated populations seem to be less prevalent and stable, suggesting potential for improvements in human-targeted methods

    On the track for an efficient detection of Escherichia coli in water : A review on PCR-based methods

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    Ensuring water safety is an ongoing challenge to public health providers. Assessing the presence of fecal contamination indicators in water is essential to protect public health from diseases caused by waterborne pathogens. For this purpose, the bacteria Escherichia coli has been used as the most reliable indicator of fecal contamination in water. The methods currently in use for monitoring the microbiological safety of water are based on culturing the microorganisms. However, these methods are not the desirable solution to prevent outbreaks as they provide the results with a considerable delay, lacking on specificity and sensitivity. Moreover, viable but non-culturable microorganisms, which may be present as a result of environmental stress or water treatment processes, are not detected by culture-based methods and, thus, may result in false-negative assessments of E. coli in water samples. These limitations may place public health at significant risk, leading to substantial monetary losses in health care and, additionally, in costs related with a reduced productivity in the area affected by the outbreak, and in costs supported by the water quality control departments involved. Molecular methods, particularly polymerase chain reaction-based methods, have been studied as an alternative technology to overcome the current limitations, as they offer the possibility to reduce the assay time, to improve the detection sensitivity and specificity, and to identify multiple targets and pathogens, including new or emerging strains. The variety of techniques and applications available for PCR-based methods has increased considerably and the costs involved have been substantially reduced, which together have contributed to the potential standardization of these techniques. However, they still require further refinement in order to be standardized and applied to the variety of environmental waters and their specific characteristics. The PCR-based methods under development for monitoring the presence of E. coli in water are here discussed. Special emphasis is given to methodologies that avoid pre-enrichment during the water sample preparation process so that the assay time is reduced and the required legislated sensitivity is achieved. The advantages and limitations of these methods are also reviewed, contributing to a more comprehensive overview toward a more conscious research in identifying E. coli in water.Diana Mendes (SFRH/BDE/33752/2009) was recipient of a fellowship from the Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) and Frilabo, Lda. The authors thank Tatiana Aguiar (Centre of Biological Engineering) for English proofreading, the financial support from the Project "Desenvolvimento de um kit de detecao e quantificacao de E. coli e bacterias coliformes em aguas", Ref. 2009/5787, Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER, the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project "Biolnd-Biotechnology and Bioengineering for improved Industrial and processes", REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER

    Microbial faecal pollution of river water in a watershed of tropical Ethiopian highlands is driven by diffuse pollution sources

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    Journal of Water and HealthTropical communities in the developing world depend heavily on riverine systems for their socioeconomic development. However, these resources are poorly protected from diffuse pollution, and there is a lack of quantitative information regarding the microbial pollution characteristics of riverine water, despite frequently reported gastrointestinal diseases. The aim of our study was to apply faecal taxation (i.e., faecal pellet counting in representative test areas to estimate the potential availability of diffuse pollution sources) in combination with a detailed microbiological faecal pollution analysis in a riverine environment to elucidate the importance of diffuse pollution. To realize this approach, ambient faecal pellets, a multiparametric data set for standard faecal indicator bacteria (SFIB), including Escherichia coli, Clostridium perfringens spores and enterococci from catchment soil and river water, and a number of riverine water physicochemical variables were analysed during a one-year cycle. We demonstrated that the abundance of ambient faecal pellets, which were consistently counted at reference sites in the catchment, was associated with faecal pollution in the river water. Water SFIB, dissolved oxygen, nutrients, conductivity and total suspended solids were strongly linked with the abundance of ambient faecal pellets in the river catchment, as demonstrated by principal component analysis (PCA). Elevated concentrations of SFIB in the riverine water in the absence of rainfall also suggested the direct input of faecal bacteria into the riverine water by livestock (e.g., during watering) and humans (e.g., during bathing). Statistical analyses further revealed that the microbiological water quality of the investigated riverine water was not influenced by SFIB potentially occurring in the soil. This study demonstrates the importance of diffuse faecal pollution sources as major drivers of the microbiological quality of riverine water in the Ethiopian highlands. In addition, the new successfully applied integrated approach could be very useful for developing predictive models, which would aid in forecasting riverine microbiological quality in tropical developing countriesinfo:eu-repo/semantics/publishedVersio

    Characteristics of the Convective Heat Transfer Coefficient at the End Winding of a Hydro Generator

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    The focus of this paper is a computational fluid dynamics (CFD) analysis of the end winding region of a hydro generator as basis for development of correlations between the convective wall heat transfer coefficient (WHTC) and speed and flow rate parameters. These correlations are used as boundary conditions for thermal networks. Furthermore, there is also a focus on the influence of the numerical settings on the correlations. This work deals with a reduced numerical model which is designed to calculate a hydro generator fast and accurately by using a steady-state simulation with the mixing plane (MP) method

    Determination of the level and source of microbial pollution in the Sava River Basin

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    Introduction. The contamination of water bodies by sewage or manure is generally determined by fecal indicator bacteria. Specific differentiation between sources of contamination is of particular importance, since the health risk to humans is usually considered higher from human, than from animal fecal contamination. Quantitative PCR (qPCR)-based assays for analysis of human- or animal-associated genetic Bacteroidetes fecal markers have gained increased popularity in the field of microbial source tracking (MST). Aim. The aim of the present study was to assess the level and source of microbial pollution in the Sava River Basin (SRB). Materials and methods. The sampling at the SRB was performed in September 2015, at 15 locations. Additional samples were collected from 4 wastewater outlets. Quantification of total coliforms, E. coli and enterococci was performed with Colilert Quanti-Tray 2000 and MPN approach. The human-associated BacHum and HF183II, the ruminant-associated BacR and the pig-associated Pig2Bac fecal markers were enumerated by quantitative PCR (qPCR). Results. According to the concentrations of fecal indicator bacteria, the river samples were scattered within the classes I and II (slight to moderate pollution). According to all monitored indicators, samples collected at 3 wastewater outlets were excessively contaminated. The results of MST revealed the presence of human-associated fecal markers BacHum and HF183II at 13 locations. The ruminant-associated BacR and the pig-associated Pig-2-Bac markers were not detected. High correlation was observed between the standard fecal indicators and human associated fecal markers. Conclusions. The results reveal human origin of fecal pollution in the SRB and indicates the urgent need for effective wastewater treatment plants in water management

    Detection of SARS-CoV-2 RNA in the Danube river in Serbia associated with the discharge of untreated wastewaters

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    In Serbia less than 13 % of collected municipal wastewaters is being treated before their release in the environment. This includes all municipal wastewater discharges from Belgrade (capital city of Serbia; population 1,700,000). Previous research has identified the impacts of raw wastewater discharges from Belgrade on the Danube River, and this study investigated if such discharges also provided a pathway for SARS-CoV-2 RNA material. Samples were collected during the most critical circumstances that occurred so far within the COVID-19 pandemics in Serbia. Grab and composite samples were collected in December 2020, during the peak of the third wave (in terms of reported cases) at the site which receives the wastewater loads in Belgrade. Grab samples collected upstream and downstream of Belgrade were also analyzed. RNA was quantified using RT-qPCR with primer sets targeting nucleocapsid (N1 and N2) and envelope (E) protein genes. SARS-CoV-2 RNA (5.97×103 to 1.32×104 copies/L) was detected only in samples collected at the site strongly impacted by the wastewaters where all three applied primer sets gave positive signals. Determined concentrations correspond to those reported in wastewater influents sampled at treatment plants in other countries indicating an epidemiological indicator function of used approach for rivers with high pollution loads in countries with poor wastewater treatment
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