15 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

    Minimizing errors in RT-PCR detection and quantification of SARS-CoV-2 RNA for wastewater surveillance

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    Wastewater surveillance for pathogens using reverse transcription-polymerase chain reaction (RT-PCR) is an effective and resource-efficient tool for gathering community-level public health information, including the incidence of coronavirus disease-19 (COVID-19). Surveillance of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in wastewater can potentially provide an early warning signal of COVID-19 infections in a community. The capacity of the world's environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is increasing rapidly. However, there are no standardized protocols or harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can cause false-positive and false-negative errors in the surveillance of SARS-CoV-2 RNA in wastewater, culminating in recommended strategies that can be implemented to identify and mitigate some of these errors. Recommendations include stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, PCR inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly when the incidence of SARS-CoV-2 in wastewater is low. Corrective and confirmatory actions must be in place for inconclusive results or results diverging from current trends (e.g., initial onset or reemergence of COVID-19 in a community). It is also prudent to perform interlaboratory comparisons to ensure results' reliability and interpretability for prospective and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization and detection for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance continues to be demonstrated during this global crisis. In the future, wastewater should also play an important role in the surveillance of a range of other communicable diseases

    Dynamics of natural prokaryotes, viruses and heterotrophic nanoflagellates in alpine karstic groundwater

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    Seasonal dynamics of naturally occurring prokaryotes, viruses, and heterotrophic nanoflagellates in two hydro-geologically contrasting alpine karst springs were monitored over three annual cycles. To our knowledge, this study is the first to shed light on the occurrence and possible interrelationships between these three groups in karstic groundwater. Hydrological and microbiological standard indicators were recovered simultaneously in order to estimate surface influence, especially during rainfall events. Data revealed a strong dependence of the microbial communities on the prevailing hydrological situation. Prokaryotic numbers averaged 5.1 × 107 and 1.3 × 107 cells L−1, and heterotrophic nanoflagellate abundance averaged 1.1 × 104 and 3 × 103 cells L−1 in the limestone spring type (LKAS2) and the dolomitic spring type (DKAS1), respectively. Viral abundance in LKAS2 and DKAS1 averaged 9.4 × 108 and 1.1 × 108 viruses L−1. Unlike in DKAS1, the dynamic spring type LKAS2 revealed a clear difference between base flow and high discharge conditions. The virus-to-prokaryotes ratio was generally lower by a factor of 2-3, at higher average water residence times. Furthermore, the high prokaryotes-to-heterotrophic nanoflagellate ratios, namely about 4700 and 5400 for LKAS2 and DKAS1, respectively, pointed toward an uncoupling of these two groups in the planktonic fraction of alpine karstic aquifers

    Application of three different methods to determine the prevalence, the abundance and the environmental drivers of culturable Vibrio cholerae in fresh and brackish bathing waters

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    Aims Three cultivation methods were used to study the prevalence and abundance of Vibrio cholerae in Eastern Austrian bathing waters and to elucidate the main factors controlling their distribution. Methods and Results Vibrio cholerae abundance was monitored at 36 inland bathing sites with membrane filtration (MF), a standard most probable number (MPN) approach and direct plating (DP). Membrane filtration yielded the most reliable and sensitive results and allowed V. cholerae detection at 22 sites with concentrations up to 39 000 CFU per 100 ml, all belonging to serogroups other than O1 and O139 and not coding for cholera toxin and toxin coregulated pilus. Direct plating turned out as an easy method for environments with high V. cholerae abundances, conductivity was the only significant predictor of V. cholerae abundance in the bathing waters at warm water temperatures. Conclusions Vibrio cholerae nonO1/nonO139 are widely prevalent in Eastern Austrian bathing waters. Instead of the standard MPN approach, MF and DP are recommended for V. cholerae monitoring. Conductivity can be used as a first easytomeasure parameter to identify potential bathing waters at risk. Significance and Impact of the Study Vibrio cholerae nonO1/nonO139 infections associated with bathing activities are an increasing public health issue in many countries of the northern hemisphere. However, there are only limited data available on the prevalence and abundance of V. cholerae in coastal and inland bathing waters. For monitoring V. cholerae prevalence and abundance, reliable and simple quantification methods are needed. Moreover, prediction of V. cholerae abundance from environmental parameters would be a helpful tool for risk assessment. This study identified the best culturebased quantification methods and a first quick surrogate parameter to attain these aims.(VLID)340099

    Wastewater-based epidemiology in countries with poor wastewater treatment — Epidemiological indicator function of SARS-CoV-2 RNA in surface waters

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    Wastewater-based epidemiology (WBE) surveillance of COVID-19 and other future outbreaks is a challenge for developing countries as most households are not connected to a sewerage system. In December 2019, SARS-CoV-2 RNA was detected in the Danube River at a site severely affected by wastewaters from Belgrade. Rivers are much more complex systems than wastewater systems, and efforts are needed to address all the factors influencing the adoption of WBE as an alternative to targeting raw wastewater. Our objective was to provide a more detailed insight into the potential of SARS-CoV-2 surveillance in Serbian surface waters for epidemiological purposes. Water samples were collected at 12 sites along the Sava and Danube rivers in Belgrade during the fourth COVID-19 wave in Serbia that started in late February 2021. RNA was concentrated using Amicon Ultra-15 centrifugal filters and quantified using RT-qPCR with primer sets targeting nucleocapsid (N1 and N2) and envelope (E) protein genes. Microbiological (faecal indicator bacteria and human and animal genetic faecal source tracking markers), epidemiological, physicochemical and hydromorphological parameters were analysed in parallel. From 44 samples, SARS-CoV-2 RNA was detected in 31, but only at 4 concentrations above the level of quantification (ranging from 8.47×103 to 2.07×104 gc/L). The results indicated that surveillance of SARS-CoV-2 RNA in surface waters as ultimate recipients could be used as an epidemiological early-warning tool in countries lacking wastewater treatment and proper sewerage infrastructure. The performance of the applied approach, including advanced sampling site characterization to trace and identify sites with significant raw sewage influence from human populations, could be further improved by adaptation of the methodology for processing higher volumes of samples and enrichment factors, which should provide the quantitative instead of qualitative data needed for WBE
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