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The recent discovery of SPINDLY (SPY)-catalyzed protein O-fucosylation revealed a novel mechanism for regulating nucleocytoplasmic protein functions in plants. Genetic evidence indicates the important roles of SPY in diverse developmental and physiological processes. However, the upstream signal controlling SPY activity and the downstream substrate proteins O-fucosylated by SPY remain largely unknown. Here, we demonstrated that SPY mediates sugar-dependent growth in Arabidopsis (Arabidopsis thaliana). We further identified hundreds of O-fucosylated proteins using lectin affinity chromatography followed by mass spectrometry. All the O-fucosylation events quantified in our proteomic analyses were undetectable or dramatically decreased in the spy mutants, and thus likely catalyzed by SPY. The O-fucosylome includes mostly nuclear and cytosolic proteins. Many O-fucosylated proteins function in essential cellular processes, phytohormone signaling, and developmental programs, consistent with the genetic functions of SPY. The O-fucosylome also includes many proteins modified by O-linked N-acetylglucosamine (O-GlcNAc) and by phosphorylation downstream of the target of rapamycin (TOR) kinase, revealing the convergence of these nutrient signaling pathways on key regulatory functions such as post-transcriptional/translational regulation and phytohormone responses. Our study identified numerous targets of SPY/O-fucosylation and potential nodes of crosstalk among sugar/nutrient signaling pathways, enabling future dissection of the signaling network that mediates sugar regulation of plant growth and development.

Background: Cell therapy can protect cardiomyocytes from hypoxia, primarily via paracrine secretions, including extracellular vesicles (EVs). Since EVs fulfil specific biological functions based on their cellular origin, we hypothesised that EVs from human cardiac stromal cells (CMSCLCs) obtained from coronary artery bypass surgery may have cardioprotective properties. Objectives: This study characterises CMSCLC EVs (C_EVs), miRNA cargo, cardioprotective efficacy and transcriptomic modulation of hypoxic human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). C_EVs are compared to bone marrow mesenchymal stromal cell EVs (B_EVs) which are a known therapeutic EV type. Methods: Cells were characterised for surface markers, gene expression and differentiation potential. EVs were compared for yield, phenotype, and ability to protect hiPSC-CMs from hypoxia/reoxygenation injury. EV dose was normalised by both protein concentration and particle count, allowing direct comparison. C_EV and B_EV miRNA cargo was profiled and RNA-seq was performed on EV-treated hypoxic hiPSC-CMs, then data were integrated by multi-omics. Confirmatory experiments were carried out using miRNA mimics. Results: At the same dose, C_EVs were more effective than B_EVs at protecting CM integrity, reducing apoptotic markers, and cell death during hypoxia. While C_EVs and B_EVs shared 70–77% similarity in miRNA content, C_EVs contained unique miRNAs, including miR-202-5p, miR-451a and miR-142-3p. Delivering miRNA mimics confirmed that miR-1260a and miR-202/451a/142 were cardioprotective, and the latter upregulated protective pathways similar to whole C_EVs. Conclusions: This study demonstrates the potential of cardiac tissues, routinely discarded following surgery, as a valuable source of EVs for myocardial infarction therapy. We also identify miR-1260a as protective of CM hypoxia. [ABSTRACT FROM AUTHOR]

This study investigates the characteristics of cardiac mesenchymal stem cell-like cells (CMSCLCs) isolated from the right atrial appendage of human donors with ischemia and a young patient with endocarditis (NE-CMSCLCs). Typical CMSCLCs from ischemic heart patients were derived from coronary artery bypass grafting procedures and compared against bone marrow mesenchymal stromal cells (BM-MSCs). NE-CMSCLCs had a normal immunophenotype, but exhibited enhanced osteogenic differentiation potential, rapid proliferation, reduced senescence, reduced glycolysis, and lower reactive oxygen species generation after oxidative stress compared with typical ischemic CMSCLCs. These differences suggest a unique functional status of NE-CMSCLCs, influenced by the donor health condition. Despite large variances in their paracrine secretome, NE-CMSCLCs retained therapeutic potential, as indicated by their ability to protect hypoxia/reoxygenation-injured human cardiomyocytes, albeit less effectively than typical CMSCLCs. This research describes a unique cell phenotype and underscores the importance of donor health status in the therapeutic efficacy of autologous cardiac cell therapy. [ABSTRACT FROM AUTHOR]

Accurate and timely identification of infections is crucial for effective treatment and controlling disease spread. While single biomarkers have traditionally served diagnostic purposes, their sensitivity and specificity limitations call for a more comprehensive approach. Simultaneous detection of multiple biomolecules shows promise in improving accuracy, expediting analysis, and enhancing pathology screening. Therefore, there is a pressing need to develop a noninvasive biosensor capable of quantifying various infection-associated biomarkers concurrently, such as albumin proteins and bacterial molecules. In this endeavor, a novel biosensor has been developed, leveraging a color-indicating optical platform that utilizes gold nanoisland films (AuNIFs) enveloped by cholesteric liquid crystals (CLCs). The integration of CLCs and AuNIFs capitalizes on their sensitive interfacial interactions, highlighting the potential for robust biosensing. Changes in biomolecule concentrations induce discernible alterations in the CLCs–AuNIFs interface alignment, profoundly impacting the hybrid plasmonic–photonic behavior of AuNIFs. The resulting CLCs–AuNIFs biosensor demonstrates exceptional sensitivity and precision in detecting E. coli concentrations and albumin levels. Notably, the biosensor achieves a label-free limit of detection, with an impressive sensitivity of 1 × 106 CFU/ml for E. coli and 10 ng/ml for bovine serum albumin (BSA). This innovative biosensor offers rapid detection, visual clarity, label-free operation, and the ability to detect multiple concentrations of both microbial agents and albumin. Changes in biomolecule concentrations induce noticeable shifts in interface alignment, thereby modulating the hybrid plasmonic–photonic dynamics of AuNIFs. The potential applications of this advancement span biomedical, microbial, and industrial sectors. This unified biosensor has the potential to revolutionize infection-related diagnostics and containment measures, serving as an ideal point-of-care solution. This ground-breaking development leads the way in multi-biomarker detection in infection diagnosis, with profound implications for future of infection diagnostics and therapeutic interventions. [ABSTRACT FROM AUTHOR]

Nanomaterials are widely used in various fields, and ongoing research is focused on developing safe and sustainable nanomaterials. Using zebrafish as a model organism for studying the potentially toxic effects of nanomaterials highlights the importance of developing safe and sustainable nanomaterials. Studies conducted on nanomaterials and their toxicity and potential risks to human and environmental health are vital in biomedical sciences. In the present review, we discuss the potential toxicity of nanomaterials (inorganic and organic) and exposure risks based on size, shape, and concentration. The review further explores various types of nanomaterials and their impacts on zebrafish at different levels, indicating that exposure to nanomaterials can lead to developmental defects, changes in gene expressions, and various toxicities. The review also covers the importance of considering natural organic matter and chorion membranes in standardized nanotoxicity testing. While some nanomaterials are biologically compatible, metal and semiconductor nanomaterials that enter the water environment can increase toxicity to aquatic creatures and can potentially accumulate in the human body. Further investigations are necessary to assess the safety of nanomaterials and their impacts on the environment and human health. [ABSTRACT FROM AUTHOR]

We have achieved a successful synthesis of a label-free, flexible, portable, and colour-indicating biosensor using cholesteric nanostructure liquid crystals (LCs), commonly referred to as cholesteric LCs (CLCs), on paper fibres. This innovative approach holds significant promise for rapid screening in precision medicine and other applications. We incorporated optically active nematic LCs in various configurations within CLCs, allowing them to rotate along different axes. When exposed to light, these LCs reflected light at specific wavelengths. By employing polarised optical microscopy and a charged couple device (CCD), we conducted titration experiments with bovine serum albumin (BSA) on the paper substrate and quantified protein concentrations based on the observed colour shifts. Utilising internal Python pixel analysis software, we evaluated the red, green, and blue colour components, which served as biomarkers for different BSA concentrations. Our results demonstrated a linear correlation between BSA concentration and colour variations. This CLC-based paper-substrate biosensor exhibits the potential to efficiently screen a large number of samples, thereby enhancing the diagnostic accuracy in clinical settings. Combining the colour-indicating and quantifiable attributes of CLCs with the affordability and portability of paper substrates, we have developed a versatile biosensor. Its ease of use, rapid response, and high sensitivity make it a promising tool for future disease detection endeavours. [ABSTRACT FROM AUTHOR]

BiVO4 with suitable band edges and a small band gap is considered an efficient photocatalyst for the oxygen evolution reaction (OER), but short charge-transfer lengths limit its photocatalytic ability. Increasing active sites can essentially enhance oxidation reactions and photocatalytic ability. The alkaline etching technique can refine the surface properties of BiVO4 by introducing oxygen vacancies and possibly establishing a heterojunction, but suitable alkaline etching methods are rarely discussed. In this study, three alkaline etching methods, including hydrothermal, soaking, and electrodeposition processes, are first applied for a constant duration to tailor the surface properties of BiVO4 as a photocatalyst for the OER. Alkaline-etched BiVO4 prepared using hydrothermal and soaking processes shows better photocatalytic abilities due to the generation of additional oxygen vacancies, while poor photocatalytic ability is found for that fabricated using electrodeposition due to the formation of less photocatalytic VO2. The highest photocurrent density of 2.38 mA cm−2 is obtained at 1.23 V versus a reversible hydrogen electrode in an electrolyte without a hole scavenger for the BiVO4 etched in the hydrothermal process, while the untreated BiVO4 presents a photocurrent density of 0.58 mA cm−2. A photocurrent retention of 92.3% is achieved after 5000 seconds of continuous illumination. The study supplies blueprints for establishing effective alkaline etching methods for enhancing the photocatalytic ability of BiVO4, with the exception of time costs. [ABSTRACT FROM AUTHOR]