One of the most important aspects of the detection of antioxidant compounds is developing a fast screening method. The screening of the overall relative antioxidant capacity (RAC) of several Romanian hydrosoluble plant extracts is the focus of this work. This is important because of the presence of increasing levels of reactive oxygen species (such as H2O2) generates oxidative stress in the human body. The consequences are a large number of medical conditions that can be helped by a larger consumption of plant extracts as food supplements, which do not necessarily contain the specified antioxidant contents. By exploiting the catalytic properties of gold nanoparticles, a specific and sensitive nanoparticle-based label-free electrochemical sensor was developed, where the working parameters were optimized for RAC screening of hydrosoluble plant extracts. First, electrochemical measurements (cyclic voltammetry and amperometry) were used to characterize different nanoparticle-based sensors, revealing the best performance of gold nanoparticle-based sensors, obtaining a RAC of 98% for lavender extracts. The sensing principle is based on the quenching effect of antioxidants for H2O2 amperometric detection, where the decrease in electrical signal suggests an increasing antioxidant capacity. The obtained results were expressed in terms of ascorbic acid and Trolox equivalents in order to be able to correlate our results with classical methods like chemiluminescence and UV-Vis spectrophotometry, where a correlation coefficient of 0.907 was achieved, suggesting a good correlation between electrochemistry and spectrophotometry. Considering these results, the optimized gold nanoparticle-based label-free sensor can be used as a simple, rapid alternative towards classical methods for relative antioxidant capacity detection of hydrosoluble plant extracts.
Background: Embryonic antigens (EA) regulate pluripotency, self-renewal, and differentiation in embryonic stem (ES) cells during their development. In adult somatic cells, EA expression is normally inhibited; however, EAs can be re-expressed by cancer cells and are involved in the deregulation of different signaling pathways (SPs). In the context of AML, data concerning the expression of EAs are scarce and contradictory. Methods: We used mass cytometry to explore the expression of EAs and three SPs in myeloid cells from AML patients and normal bone marrow (NBM). Imaging flow cytometry was used for morphological assessment of cells in association with their OCT3/4 expression status (positive vs. negative). Results: An overall reduction in or absence of EA expression was observed in immature myeloid cells from AML patients compared to their normal counterparts. Stage-specific embryonic antigen-3 (SSEA-3) was consistently expressed at low levels in immature myeloid cells, whereas SSEA-1 was overexpressed in hematopoietic stem cells (HSCs) and myeloblasts from AML with monocytic differentiation (AML M4/M5). Therefore, these markers are valuable for distinguishing between normal and abnormal myeloid cells. These preliminary results show that the exploration of myeloid cell intracellular SPs in the setting of AML is very informative. Deregulation of three important leukemogenic SPs was also observed in myeloid cells from AML. Conclusions: Exploring EAs and SPs in myeloid cells from AML patients by mass cytometry may help identify characteristic phenotypes and facilitate AML follow-up.
The Kleihauer–Betke (KB) test allows the detection of fetal red blood cells (containing fetal hemoglobin, HbF) in the maternal blood to identify and quantify potential fetal-maternal hemorrhages. In certain cases, detecting fetal red blood cells with conventional staining is difficult. False-positive results or overestimation of the quantity of fetal red blood cells may occur in cases of maternal hemoglobinopathy. In this study, we developed a new staining protocol to facilitate the reading of difficult smears and improve the precision of the quantification of fetal red blood cells; we also analyzed the performance of this new method. This study assessed blood samples with and without hemoglobin abnormalities, which present difficulties when interpreting the KB test. The new staining formula is based on an improved elution technique and the use of a different stain instead of hematoxylin. To test this staining method, 16 samples from patients with abnormal hemoglobin electrophoresis and 14 samples from patients with normal hemoglobin electrophoresis were analyzed using the KB test with the classical staining method and the new staining method. In addition, a second series was prepared using the same samples spiked with fetal red blood cells from newborn blood, to compare the accuracy of the two methods in identifying fetal red blood cells. In the 60 slides analyzed with both staining methods, we found that the new technique improved the accuracy from 78 to 85%; lowered the coefficient of variation between the operators, which decreased from 20.7% to 12.7%; increased the specificity in our population from 56 to 70%; and decreased the number of false-positive cases by 30%. We successfully developed a new staining technique that facilitates the reading of difficult slides and improves the specificity of the detection of fetal red blood cells. This technique is recommended as a secondary method to use before sending the sample for additional exploration.
Background The Kleihauer–Betke (KB) test allows the detection of fetal red blood cells (containing fetal hemoglobin, HbF) in the maternal blood to identify and quantify potential fetal-maternal hemorrhages. In certain cases, detecting fetal red blood cells with conventional staining is difficult. False-positive results or overestimation of the quantity of fetal red blood cells may occur in cases of maternal hemoglobinopathy. In this study, we developed a new staining protocol to facilitate the reading of difficult smears and improve the precision of the quantification of fetal red blood cells; we also analyzed the performance of this new method. This study assessed blood samples with and without hemoglobin abnormalities, which present difficulties when interpreting the KB test. Methods The new staining formula is based on an improved elution technique and the use of a different stain instead of hematoxylin. To test this staining method, 16 samples from patients with abnormal hemoglobin electrophoresis and 14 samples from patients with normal hemoglobin electrophoresis were analyzed using the KB test with the classical staining method and the new staining method. In addition, a second series was prepared using the same samples spiked with fetal red blood cells from newborn blood, to compare the accuracy of the two methods in identifying fetal red blood cells. Results In the 60 slides analyzed with both staining methods, we found that the new technique improved the accuracy from 78–85%; lowered the coefficient of variation between the operators, which decreased from 20.7–12.7%; increased the specificity in our population from 56–70%; and decreased the number of false-positive cases by 30%. Conclusions We successfully developed a new staining technique that facilitates the reading of difficult slides and improves the specificity of the detection of fetal red blood cells. This technique is recommended as a secondary method to use before sending the sample for additional exploration.