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Objective: During the COVID-19 pandemic, laboratories have used various extraction and amplification kits, associated with different auxiliary materials. This study aims to investigate how different types of plates may affect RT-PCR performance. Methods: Data on the positive controls (PCs) of RT-PCR runs for SARS-CoV-2 detection between December 2020 and April 2022 was collected retrospectively in the Molecular biology department of the County Emergency Clinical Hospital of Târgu Mureș's clinical laboratory. The materials used consisted in MOLgen SARS-CoV-2 (Adaltis) and EliGene COVID19 CONFIRM 500 R amplification kits, 96-well full-skirted white and clear plates, and clear films. Microsoft Excel was used for the database and it included information about Cycle threshold (Ct) and maximum fluorescence. Statistical analysis, performed in MedCalc, consisted of Grubbs test, Kolmogorov–Smirnov Test, F test, T student test, and Mann-Whitney test to compare central tendencies. The significance threshold was set at p<0.05. Results: The Ct comparison for MOLgen kit white plates vs clear plates: FAM channel- U=1052.5, Z=2.07, p=0.038, medians for white plates and clear plates were 22.80 and 23.25, respectively; ROX channel- U=784, Z=3.21, p=0.001, medians 21.93 and 21.43, respectively; Cy5 channel- U=1028.5, Z=1.95, p=0.518, medians 22.12, 21.75, respectively. For EliGene kit: U=848.5, Z=3.27, p=0.001, medians 28.26 (white plates) and 28.0 (clear plates). Comparison of the maximum fluorescence reached on both kits with white and clear plates computed p values <0.0001. Conclusions: Between white and clear plates there are statistically significant differences considering Ct values and maximum read fluorescence, but with no impact on test outcome. [ABSTRACT FROM AUTHOR]

Objective: In this study, we aimed to investigate the effect of transient postprandial in vivo and prolonged experimental in vitro hyperlipidemia on human peripheral blood monocytes. Methods: Peripheral blood was collected from seven healthy subjects after an overnight fast and three hours after a standardized high-fat meal. Both fasting and postprandial samples were stained for surface markers CD14/CD11b and intracellular lipids using BODIPY493/503. Postprandial samples only were used for isolation of peripheral blood mononuclear cells that were further incubated overnight with postprandial hyperlipidemic autologous plasma, then stained as described above. All samples were analyzed on a FACSAria III flow cytometer. Results: Flow cytometric analysis revealed two monocyte populations (CD14+): CD14low and CD14high. In fasting, these populations show similar morphology (FSC/SSC), but different expressions of CD14, CD11b, and BODIPY493/503. At three hours postprandially, a moment of maximum hyperlipidemia, neither population suffered significant changes. After the 24-hour incubation, cell activation was observed in both populations: similar fold change increase in SSC, increase in FSC for CD14high cells only, similar foldchange increase in CD14, slightly higher foldchange increase in CD11b for CD14low monocytes, and significantly higher foldchange increase in lipid content for CD14high monocytes. CD14high monocytes appear to undergo a more intense activation than CD14low monocytes. Conclusions: We conclude that all monocytes react after prolonged in vitro exposure to plasma lipids, each subset having its own activation pattern. All monocyte types may play a role in inflammation and the development of plaques. Monocyte assays are a valuable tool for the investigation of atherosclerosis at the cellular level. [ABSTRACT FROM AUTHOR]