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ABSTRACT Reliable detection of mecA and mecC-mediated beta-lactam resistance using automated antimicrobial susceptibility test systems is critical for patient care. The aim of this study was to compare the performance of the new cefoxitin screen test (oxsf02n) on the Vitek 2 card (Vitek 2) and BD Phoenix PMC-100 Gram-Positive AST Panel (Phoenix) against the reference method for the detection of mecA (and mecC)-mediated beta-lactam resistance. Two hundred fifty clinical fresh and stock Staphylococcus spp. isolates were included. There were 120 mecA-positive, 10 mecC-positive, and 120 mecA and mecC-negative isolates. Cefoxitin screen and oxacillin tests were performed on Vitek 2 and Phoenix and by their respective reference methods (disk diffusion for the cefoxitin screen test and broth microdilution for oxacillin) for all isolates. PCR testing was also performed to confirm the presence of mecA and/or mecC genes. Results from each system were compared to the reference methods. Statistical hypotheses were evaluated both for Vitek 2 compared to the reference methods and Vitek 2 compared to the Phoenix. Compared to the reference method, the Vitek 2 cefoxitin screen test had 100% sensitivity/98% specificity and the Phoenix cefoxitin screen test had 84% sensitivity/100% specificity for the detection of mecA (and mecC)-mediated beta-lactam resistance. When the oxacillin test was combined with the cefoxitin screen for Vitek 2, the sensitivity and specificity were unchanged. However, when the oxacillin and cefoxitin screen tests were combined for the Phoenix, the sensitivity increased to 100% and the specificity remained unchanged (100%). When considering cefoxitin alone, the Vitek 2 screen test showed a higher sensitivity than the Phoenix for the detection of mecA and mecC-mediated beta-lactam resistance. However, currently, both systems use a combination of the cefoxitin and oxacillin tests to interpret the final result, and both reached a high level of performance when cefoxitin and oxacillin results were combined.IMPORTANCEThis research marks the inaugural evaluation of the revamped cefoxitin screen test version in Vitek 2, juxtaposing it against reference methods and a primary competitor BD Phoenix.

Background: Direct oral anticoagulants (DOACs) cause unwanted interference in various hemostasis assays, including lupus anticoagulant (LA) testing, where false positive and false negative identification may occur. DOAC Stop (DS) is an activated charcoal (AC) product used to specifically and effectively adsorb DOACs from test plasma. This process normally requires plasma treatment, centrifugation and plasma separation prior to tests, but inexperienced operators may also inadvertently transfer residual AC particles, thereby potentially adversely affecting clot detection. Methods: We hypothesized that residual DS might not be problematic for mechanical clot detection. We therefore investigated the potential impact of DS and a new DS liquid (DS-L) product on clotting tests using a mechanical clot detection system. Varying concentrations of DS were added to normal and abnormal plasmas with and without DOAC presence. Clotting tests including PT, APTT and dRVVT were performed directly in the analyzer without plasma/DS centrifugation. Results: DS up to double the recommended treatment level had only minor effects on all test results, despite completely obscuring visibility in the plasma/reagent mix. This confirms that the centrifugation step may be able to be omitted when using mechanical detection systems. Conclusions: Should DS carryover into treated plasmas occur, this should not cause issues with testing performed on mechanical clot-sensing devices. Moreover, we hypothesize that DS can be used directly in these systems, without the need for centrifugation, thereby simplifying its many potential applications. [ABSTRACT FROM AUTHOR]

A total of 138 serum samples from pigs and cattle vaccinated against foot-and-mouth disease virus (FMDV) of one or two serotypes or infected with FMDV were used for testing of 24 enzyme-linked immunosorbent assay (ELISA) diagnostic tests-systems for detection of antibodies against FMDV structural proteins produced by 6 manufacturers (Federal Centre for Animal Health, Prionics, IZSLER, Innovative Diagnostics, BIONOTE and MEDIAN Diagnostics) for their serotype-specificity. All used test-systems detected apparent serotype-specific activity (homologous reaction) as well as cross-reacting virus-specific antibodies that was accounted for some reasons related to conservative epitopes in amino acid sequence of FMDV virion capsid VP1–VP3 polypeptides, accessibility of internal conservative epitopes of VP4 polypeptide for the animal’s immune system during virus replication or vaccine antigen (virus) destruction in the animal’s body in the process of immunity development, as well as the pilot anti-FMD vaccine composition, etc. Nevertheless, the analysis of a large data set (about 3,500 tests) showed that the homologous serotype-specific reaction in general was significantly higher and predominant, the proportion of virus-specific non-protective antibodies, including cross-reacting ones, was not significant and did not distort the results of ELISA tests of anti-FMD vaccine for its immunogenicity. Inconclusive test results require confirmation with other serological tests. Complex tests for FMDV using different diagnostic methods such as ELISA with standard and reference test-systems and/or virus neutralization test in cell culture are to be considered as the best option.

The process of electrification and digitalisation that the electricity distribution sector is currently undergoing is a true revolution, imposing more changes in recent years than in dozens of previous years. The electrification process involves the deployment of more and more so-called flexible devices in the distribution network, such as electric vehicles, heat pumps, photovoltaic systems with or without electrical storage. Electrification will bring obvious benefits such as decarbonisation of the energy system and reduction of dependence on fossil fuels, but it is also true that it will put the distribution grid under stress never seen before. The introduction of digital twins for the real-time management of distribution networks, the precise calculation of hosting capacity at each point of the network, the analysis of safety in protections, etc., is already a reality even in low-voltage networks. Some of these methodologies involve the use of precise mathematical models of distribution networks, and this is precisely what is presented in this article. A set of 3 test networks of European type networks, generated with real data representing a 100% urban low voltage distribution system, a 100% rural low voltage distribution system and a mixed medium/low voltage system representing a network in an industrial/commercial environment. As part of the work, OpenDSS models of these networks are attached, which can be of great value to the research community in many types of studies.

The most accurate laboratory methods for thrombophilia diagnostics are based on the quantitative determination of the blood plasma specific markers that appear as a result of the coagulation cascade activation. Soluble fibrin and D-dimer belong to the main of the last ones. An alteration in the concentration of such markers can indicate thrombin concentration growth and the formation of soluble oligomeric fibrin. It should be pointed out that simultaneous detection of these markers can establish the correlation between the accumulation of soluble fibrin and fibrinolysis and nowadays is provided only by enzyme-linked immunoassay. Thus, the usage of immunodiagnostic test systems for the detection of thrombophilia markers is highly relevant today. The important components of immunodiagnostic test system are protein calibrators, the isolation standardization of which plays a key role for accurate construction of a calibration curve and obtaining objective results as a consequence. Aim. The objective of this study was to develop the soluble fibrin and D-dimer isolation methodology and its standardization for their further use as the protein calibrators for thrombophilia markers detecting immunodiagnostic test systems. Materials and Methods. Soluble fibrin and D-dimer were isolated from collected human blood by fibrinogen salting out with further fibrin polymerization with thrombin and hydrolysis with plasmin. Quality control of the obtained proteins was carried out using SDS-PAGE and turbidimetric measurements with further checking of the proteins as calibrators for the thrombophilia markers detecting immunoassay. Results. Obtained proteins meet the necessary specifications and can be used as calibrators for immunodiagnostic test systems. Soluble fibrin and D-dimer were checked by SDS-PAGE for the absence of impurities. Turbidimetric measurements showed the polymerization capability of the soluble fibrin and the inhibition of the polymerization by D-dimer. Conclusion. The standardized isolation methodology of soluble fibrin and D-dimer can be used to obtain protein calibrators for appropriate immunodiagnostic test systems.

Mental and physical health components are critical in child’s development. However, adolescents are especially vulnerable group presenting multiple health risks of chronic disease, sleeping and eating problems. Moreover, the long time spent at screens increases possibility to develop addictions. There is a lack of comprehensive interdisciplinary assessment tools for adolescents, to assess their mental health components, and provide preventive activities. It is very important to develop a methodology that can accurately assess the minor cognitive and health deviations that can be caused by an unhealthy lifestyle and excessive time spent on screens. This research explores the possibilities to record and compare parameters of cognitive abilities, reaction time, and working memory using Vienna test systems for different groups of adolescents by their physical activity and health levels. The results of this study demonstrated that the reaction time in adolescents was shorter using the leading hand in comparison with using the non-leading hand, 272.842 ± 44.001ms vs 306.631 ± 57.081ms on Vienna test for low physical activity (LPA) adolescents group. In the STROOP test color evaluation results were faster than word reading test results. The median of reaction time of LPA adolescents for color evaluation was 0.897 ± 0.221ms and 0.968 ± 0.15ms for reading. Vienna test system has specific tests that can be used to determine memory parameters, providing different assessment approaches to compare the obtained results. Group of adolescents with mild chronic health conditions performs statistically significantly lower parameter in particular tests in comparison with adolescents with low and high physical activity. [ABSTRACT FROM AUTHOR]

Bulgarian Rosa damascena Mill. is has been known since ancient times for its high-quality oil, hydrosol, and other aromatic products. Rose hydrosol has various biological activities, but no research on its anticytotoxic/antigenotoxic effects exists. This study aimed to assess its defense potential against the genotoxin N-methyl-N′-nitro-N-nitrosoguanidine and to test its cytotoxic/genotoxic activity in plant and human lymphocyte test systems. Endpoints for cytotoxicity (mitotic index and nuclear division index) and genotoxicity (chromosome aberration and micronuclei) were used. Hydrosol was applied as a single treatment in concentrations ranging from 3% to 20% (4 h) to assess its cytotoxic and genotoxic effects. Its protective potential against MNNG was tested by applying an experimental scheme involving (i) conditioning treatment with non-toxic or slightly toxic concentrations of hydrosol, followed by genotoxin challenge (50 μg/mL) with a 4 h intertreatment time and (ii) treatment with hydrosol and mutagen with no time between the treatments. Hydrosol induces low cytotoxicity and clastogenicity, demonstrating cytoprotective/genoprotective effects against the mutagen in both applied test systems. The hydrosol defense potential was expressed by a more than twofold reduction in both chromosomal aberrations and micronuclei and by enhancing the mitotic activity compared with that of the mutagen, regardless of the experimental conditions. The results are promising for further hydrosol applications in pharmaceutical and medical practice. [ABSTRACT FROM AUTHOR]

Reliable detection of mec A and mec C-mediated beta-lactam resistance using automated antimicrobial susceptibility test systems is critical for patient care. The aim of this study was to compare the performance of the new cefoxitin screen test (oxsf02n) on the Vitek 2 card (Vitek 2) and BD Phoenix PMC-100 Gram-Positive AST Panel (Phoenix) against the reference method for the detection of mec A (and mec C)-mediated beta-lactam resistance. Two hundred fifty clinical fresh and stock Staphylococcus spp. isolates were included. There were 120 mec A-positive, 10 mec C-positive, and 120 mec A and mec C-negative isolates. Cefoxitin screen and oxacillin tests were performed on Vitek 2 and Phoenix and by their respective reference methods (disk diffusion for the cefoxitin screen test and broth microdilution for oxacillin) for all isolates. PCR testing was also performed to confirm the presence of mec A and/or mec C genes. Results from each system were compared to the reference methods. Statistical hypotheses were evaluated both for Vitek 2 compared to the reference methods and Vitek 2 compared to the Phoenix. Compared to the reference method, the Vitek 2 cefoxitin screen test had 100% sensitivity/98% specificity and the Phoenix cefoxitin screen test had 84% sensitivity/100% specificity for the detection of mec A (and mec C)-mediated beta-lactam resistance. When the oxacillin test was combined with the cefoxitin screen for Vitek 2, the sensitivity and specificity were unchanged. However, when the oxacillin and cefoxitin screen tests were combined for the Phoenix, the sensitivity increased to 100% and the specificity remained unchanged (100%). When considering cefoxitin alone, the Vitek 2 screen test showed a higher sensitivity than the Phoenix for the detection of mec A and mec C-mediated beta-lactam resistance. However, currently, both systems use a combination of the cefoxitin and oxacillin tests to interpret the final result, and both reached a high level of performance when cefoxitin and oxacillin results were combined.IMPORTANCEThis research marks the inaugural evaluation of the revamped cefoxitin screen test version in Vitek 2, juxtaposing it against reference methods and a primary competitor BD Phoenix., Competing Interests: I.Y.-T., C.D.G., and S.F. are employees of bioMérieux. Funding for the study was provided by bioMérieux