We report the roll-to-roll (R2R) magnetron sputtering deposition of photochromic oxygen-containing yttrium hydride (YHO) and bilayer YHO/Cu thin films on flexible polyethylene terephthalate substrates, enabling their integration as replaceable coverings or laminates. This scalable fabrication route yields multifunctional coatings that combine reversible optical modulation with antimicrobial activity. The YHO films are nanocrystalline (similar to 13 nm crystallite size) with a fine-grained surface morphology. Single-layer YHO films exhibit similar to 58 % average visible transmittance, whereas YHO/Cu bilayers show similar to 47 % mainly due to reflectance from the Cu film. The films darken reversibly, achieving a relative photochromic contrast of 15-19 % after 1 h of UV-violet illumination, and bleach with a time constant of similar to 10 min after the illumination. Notably, higher deposition pressures yield lower contrast but faster bleaching, indicating an inverse correlation between optical contrast and bleaching speed. The addition of a Cu top film endows potent antimicrobial performance: the best-performing YHO/Cu bilayers achieved a 5.2 log reduction in Escherichia coli, a 2.2 log reduction in Staphylococcus aureus, and complete inactivation of SARS-CoV-2 (>3.8 log reduction) after 24 h of incubation, indicating broad-spectrum efficacy. The R2R production of YHO-based thin films demonstrates the industrial potential of large-area photochromic coatings with integrated antimicrobial functionality.
Abstract Background Long-COVID affects at least 10% of COVID-19 survivors, displaying debilitating symptoms across multiple organ systems. Despite the widespread prevalence, Long-COVID aetiology remains poorly understood, but emerging evidence points to immune dysregulation as a potential mechanism involved in its development or persistence. Methods This study presents a unique analysis of the peripheral blood mononuclear cell transcriptomic profile of COVID-19 and Long-COVID patients at single-cell resolution. We reconstructed the cell state and intercellular communication using differentially expressed gene profiling and ligand–receptor interaction analyses. Results Our results reveal altered T and natural killer cell subset proportions, diminished proliferating lymphocyte and B cell signalling capacity, and the expression of exhaustion and cytotoxicity associated genes 1.5–2 years post-infection, suggesting incomplete immune recovery. Distinct interferon responses in these cell populations at the acute phase for patients who go on to develop Long-COVID indicate early disease mediator potential. Conclusions Collectively, these findings provide insight into the immune processes underlying the progression of COVID-19 into a chronic Long-COVID state. The observed changes in immune cell subsets at the acute phase of the infection may be predictive of Long-COVID progression and could be useful in understanding disease aetiology while the observed long-term effects are crucial to developing therapeutic and diagnostic tools.
Resistance to Vemurafenib (VEM), a targeted BRAFV600E inhibitor, was examined in the metastatic paratetraploid (XX, abnormal Y chromosome) melanoma cell line, SkMel28. During the first week of treatment, pERK suppression coincided with transcriptomic and phenotypic changes related to senescence, autophagy/mitophagy, neuro-melanogenesis, and cell co-alignment. By the second week, MAPK-ERK signalling was restored, coinciding with surmounting the G1/S checkpoint, G2M checkpoint delay, mitotic slippage (MS), and downregulation of senescence and melanogenesis. The dynamics of melanogenesis and MS were highly correlated. By days 12-15, ∼8% of cells with melanin remnants exhibited hyperploidy and multinucleation, some arranged as rosettes, encased by a Zona pellucida-positive structure reminiscent of oocytes, zygotes, or blastulae, occasionally yielding cellularised sub-cells or stalling in diapause. These parasexual processes eventually ceased; cells resumed proliferative clonogenic growth and their initial mito-meiotic, mesenchymal profile. Transcriptomic analysis confirmed the reversal of their cell fate direction: from senescence-induced neuro-melanogenesis to its suppression and activation of female meiosis-like and mitosis states. The transition point of this cell-fate reversal coincided with S-phase resumption, highlighted by replication delay and activation of the FOS-TEAD/Hippo axis of the "female pregnancy" (stress-response, embryonal placentation, vascularisation, stemness, anti-apoptosis) gene ontology module. We conclude that resistance to VEM in SkMel28 cells encompasses the transition between three possible cell fates: (1) senescence/differentiation, (2) reprogramming/blastulation, and (3) recovery of the proliferative mito-meiotic profile. The coexpression of senescence, reprogramming and gametogenetic genes in a dataset of late-stage melanoma patient samples supports these results.
Background Advances in culture-free microbial research have considerably expanded the known genomic diversity of prokaryotes and viruses associated with any imaginable environment. However, only a tiny fraction of this diversity has been obtained in culture, locking most of it to merely biological sequences of various contiguities, regardless of the environment. Yet, many environments are housing relatively easily culturable biological entities sufficiently distinct from those cultures so far, allowing for a better understanding of at least some of their manifestations and impacts in the said environment by virtue of culture-based studies. Expectedly, undersampled and understudied environments serve as a low-hanging fruit for uncovering novel culturable microbiological entities with exciting biology, given access to the samples. Results Attempts to culture novel phage-host pairs from ice-free soil samples collected at Waddington Bay, Graham Coast, Antarctica, during the First Latvian Antarctic Expedition have resulted in the recovery of a unique Psychrobacillus siphophage Perkons that infects a Psychrobacillus isolate designated as "L4" originating from the same source material. Results of the whole genome sequencing revealed phage Perkons to be unique in terms of its overall genomic nucleotide sequence similarity, whereas isolate L4 was found to be most closely related to Psychrobacillus glaciei strain PB01 and Psychrobacillus sp. L3 (latter of which originated from the same source material, but was not susceptible to infection by Perkons), yet demonstrated sufficient differences from both. The unexpected presence of several integrase genes in the genome of Perkons has prompted lysogenization experiments of the host strain, revealing site-specific integration into the chromosome of Psychrobacillus sp. L4 resulting in the disruption of an ORF encoding a flotillin-like protein floA. While the temperate nature of phage Perkons hindered replicability of the classical microbiological assays, ddPCR-based investigations have given a hint at the Perkons-L4 interaction dynamics and verified spontaneous Perkons induction from the lysogenized host. Conclusions Isolation and characterization of Psychrobacillus sp. L4 and unique temperate bacteriophage Perkons expand the known culturable microbial diversity. Characterization of bacteriophage Perkons presented in this work is expected to provide baseline knowledge of the Perkons-like phages, more of which are anticipated to be uncovered in the future owing to both culture-independent and culture-dependent experimental efforts.
Co-amplification of host DNA remains a significant obstacle in plant microbiome profiling, as universal taxonomic markers, such as the 16S rRNA gene, are also present in plant organellar genomes. While strategies like blocking primers can enrich bacterial reads, they rely on prior sequence knowledge and may introduce bias. We developed a sequence-independent approach that suppresses host DNA amplification by combining physical pretreatments that selectively compromise plant cell integrity with propidium monoazide (PMA) treatment, which binds exposed DNA and prevents its PCR amplification. We observed that various pretreatments-including cryopreservation and mechanical disruption enhanced plant cell susceptibility to PMA without affecting bacterial cells. The applied approach resulted in significantly increased proportions of bacterial reads and improved detection of bacterial diversity in downstream NGS. Compared to sequence-dependent strategies such as blocking primers, this method achieved comparable or superior performance in reducing host DNA interference-particularly in low-biomass samples. Our results establish cryopreservation-enhanced PMA-PCR as a robust, sequence-independent method for high-resolution plant microbiome profiling.
