COVID-19, caused by the SARS-CoV-2 virus, manifests with a wide range of clinical symptoms that vary from mild respiratory issues to severe respiratory distress. To effectively manage and predict the outcomes of the disease, it is important to understand the molecular mechanisms underlying its severity. This study focuses on analyzing and comparing the expression patterns of microRNAs (miRNAs) in serum, urine, and nasopharyngeal samples from patients with mild, moderate, and severe COVID-19. The aim is to identify potential associations with disease progression and discover suitable markers for diagnosis and prognosis. Our findings indicate the consistent upregulation of miR-21, miR-146a, and miR-155 in urine, serum, and nasopharyngeal samples from patients with mild COVID-19. In moderate cases, there were more significant changes in miRNA expression compared to mild cases. Specifically, miR-let-7 demonstrated upregulation, while miR-146b exhibited downregulation. The most notable alterations in miRNA expression profiles were observed in severe COVID-19 cases, with a significant upregulation of miR-223. Moreover, our analysis using Receiver-operating characteristic (ROC) curves demonstrated that miR-155, miR-let-7, and miR-223 exhibited high sensitivity and specificity, suggesting their potential as biomarkers for distinguishing COVID-19 patients from healthy individuals. Overall, this comparative analysis revealed distinct patterns in miRNA expression. The overlapping expression patterns of miRNAs in urine, serum, and nasopharyngeal samples suggest their potential utility in discriminating disease status.

According to information from the World Health Organization, the world has experienced about 430 million cases of COVID-19, a world-wide health crisis caused by the SARS-CoV-2 virus. This outbreak, originating from China in 2019, has led to nearly 6 million deaths worldwide. As the number of confirmed infections continues to rise, the need for cutting-edge techniques that can detect SARS-CoV-2 infections early and accurately has become more critical. To address this, the Federal Drug Administration (FDA) has issued emergency use authorizations (EUAs) for a wide range of diagnostic tools. These include tests based on detecting nucleic acids and antigen-antibody reactions. The quantitative real-time reverse transcription PCR (qRT-PCR) assay stands out as the gold standard for early virus detection. However, despite its accuracy, qRT-PCR has limitations, such as complex testing protocols and a risk of false negatives, which drive the continuous improvement in nucleic acid and serological testing approaches. The emergence of highly contagious variants of the coronavirus, such as Alpha (B.1.1.7), Delta (B.1.617.2), and Omicron (B.1.1.529), has increased the need for tests that can specifically identify these mutations. This article explores both nucleic acid-based and antigen-antibody serological assays, assessing the performance of recently approved FDA tests and those documented in scientific research, especially in identifying new coronavirus strains.

Background/Objectives: Targeting bacterial virulence mechanisms and associated inflammation represents a compelling strategy to disarm pathogens without imposing selective survival pressure. While Euphorbia tirucalli (Pencil Cactus) synthesizes potent bioactive secondary metabolites, the extreme irritancy of its raw phytocomplex has historically hindered its biomedical application. This study aimed to overcome these limitations via polymeric nanoencapsulation, leveraging the metabolome of E. tirucalli stem extract to attenuate bacterial virulence and cellular inflammation. Methods: Chemical profiling was conducted via high-resolution LC-Q-Orbitrap HRMS. Polymeric nanoparticles were fabricated using different stabilizers (Tween 80, ethyl cellulose, and PEG 6000) and characterized using TEM, DLS, and XRD. In vitro release kinetics were analyzed in PBS (pH 7.4). Biological evaluations encompassed agar well diffusion, broth microdilution (MIC/MBC), qRT-PCR transcriptional analysis of virulence/biofilm genes in standard bacterial strains (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli), and anti-inflammatory profiling in LPS-stimulated RAW 264.7 murine macrophages via ELISA. Results: HRMS tentatively annotated 46 metabolites, predominantly methoxy flavonoids, flavonoid glycosides, and phenolic acids. The PEG 6000-stabilized nanoformulation achieved optimal colloidal properties (particle size: 65 ± 15 nm, PDI: 0.19 ± 0.03, and zeta potential: −29.6 ± 2.1 mV) alongside sustained Fickian release. Nanoencapsulation markedly suppressed key target genes (toxA, exoS, algD, papC, fimH, and cna;p< 0.05). Broth microdilution confirmed substantial antibacterial enhancement, where the optimized nanoformulation (F3) achieved an 8-fold reduction in MIC/MBC values (15.6 µg/mL vs. 125 µg/mL for crude extract) across S. aureus, E. coli, and P. aeruginosa. In LPS-stimulated RAW 264.7 macrophages, nanoformulations F2 and F3 significantly decreased TLR-2 levels from 5.99 to 5.21 and 5.18, and IL-17 expression from 2.54 to 1.87 and 1.85, respectively. Similarly, NF-κB expression dropped from 3.12 in the LPS group to 2.34 (F2) and 2.27 (F3) (p= 0.0149), confirming pronounced attenuation of acute inflammatory signaling. Conclusions: Polymeric nanoencapsulation of Euphorbia tirucalli extract successfully enhanced antibacterial efficacy and attenuated inflammatory cascades, demonstrating improved in vitro biocompatibility in macrophage cultures. The optimized formulation (F4) achieved an 8-fold reduction in MIC/MBC thresholds (15.6 µg/mL) alongside the downregulation of biofilm and virulence determinants (fimH, papC, and algD). Furthermore, the nanosystems effectively suppressed pro-inflammatory signaling in LPS-stimulated RAW 264.7 macrophages via the TLR-2/NF-κB axis. Overall, this nanoplatform demonstrates improved cellular compatibility and functions as an effective candidate for dual antibacterial and anti-inflammatory interventions.