The therapeutic activities of food-derived bioactive proteins and peptides are attracting increased attention within the research community. Medicinal plants used in traditional medicines are an excellent source of bioactive proteins and peptides, especially those traditionally prepared by water extraction for use as tea or food supplement. In this study, novel bioactive peptides were isolated from enzymatic digests of 33 Thai medicinal plants. The inhibitory activity of each against dengue virus (DENV) infection was investigated. Of 33 plants, peptides from Acacia catechu extract demonstrated the most pronounced anti-DENV activity. Half maximal inhibitory concentration of 0.18 μg/ml effectively inhibited DENV foci formation. Treatment with 1.25 μg/ml crude peptide extract could reduce virus production less than 100-fold with no observable cell toxicity. Peptide sequences were determined by high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry. Two bioactive peptides isolated from Acacia catechu inhibited DENV foci formation >90% at the concentration of 50 μM; therefore, they are recommended for further investigation as antiviral peptides against DENV infection.

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Background: The circulating rare cell population is diverse and rich in diagnostic information. Its characterization and clinical exploitation by cell-based liquid biopsy is an ongoing research task. Bone marrow is one of the major contributors to the peripheral blood rare cell population and, consequently, determines individual rare cell profiles thus depending on bone marrow health status. Bone marrow damage has been associated with aggressive or late-stage systemic diseases and egress of various bone marrow cells into the blood circulation. The association of quantity and heterogeneity of circulating erythroblast with bone marrow damage is of particular interest. Methods: Circulating CD71high/CD45-/Hoechsthigh blast cells from healthy, noncancer- and cancer-afflicted donors were enriched by CD45 depletion and analyzed by immunofluorescence microscopy. Results: A new finding of aberrant and mitotic circulating erythroid-like cells that appear similar across blood donors afflicted with various systemic pathologies is reported. Further presented is a classification of said erythroblast-like cells in nine subcategories according to morphological differences between phenotypically similar cells. Conclusion: Aberrant and mitotic bone marrow-derived rare circulating erythroid-like cells can be detected in the blood of afflicted individuals but not in healthy donors, suggesting the cause of bone marrow damage.

Background Breast cancer residual disease assessment in early-stage patients has been challenging and lacks routine identification of adjuvant therapy benefit and objective measure of therapy success. Liquid biopsy assays targeting tumor-derived entities are investigated for minimal residual disease detection, yet perform low in clinical sensitivity. We propose the detection of CD44−related systemic inflammation for the assessment of residual cancer. Methods Circulating CD44+/CD45− rare cells from healthy, noncancer- and cancer-afflicted donors were enriched by CD45 depletion and analyzed by immuno-fluorescence microscopy. CD44+ rare cell subtyping was based on cytological feature analysis and referred to as morphological index. AUC analysis was employed for identification of the most cancer-specific CD44+ subtype. Results The EpCam−/CD44+/CD24−/CD71−/CD45−/DNA+ phenotype alludes to a distinct cell type and was found frequently at concentrations below 5 cells per 5 mL in healthy donors. Marker elevation by at least 5 × on average was observed in all afflicted cohorts. The positive predicted value for the prediction of malignancy-associated systemic inflammation of a CD44+ rare cell subtype with a higher morphological index was 87%. An outlook for the frequency of sustained inflammation in residual cancer may be given to measure 78%. Conclusion The CD44+ rare cell and subtype denotes improvement in detection of residual cancer disease and may provide an objective and alternative measure of disease burden in early-stage breast cancer.