Transcriptome Analysis Reveals Silver Nanoparticle-Decorated Quercetin Antibacterial Molecular Mechanism

Facile and simple method is developed to synthesize silver-nanoparticle-decorated quercetin nanoparticles (QA NPs). Modification suggests that synergistic quercetin (Qe) improves the antibacterial effect of silver nanoparticles (Ag NPs). Characterization experiment indicates that QA NPs have a diameter of approximately 10 nm. QA NPs show highly effective antibacterial activities against drug-resistant <i>Escherichia coli</i> (<i>E. coli</i>) and <i>Staphylococcus aureus</i> (<i>S. aureus</i>). We explore antibacterial mechanisms using <i>S. aureus</i> and <i>E. coli</i> treated with QA NPs. Through morphological changes in <i>E. coli</i> and <i>S. aureus</i>, mechanisms are examined for bacterial damage caused by particulate matter from local dissociation of silver ion and Qe from QA NPs trapped inside membranes. Moreover, we note that gene expression profiling methods, such as RNA sequencing, can be used to predict discover mechanisms of toxicity of QA NPs. Gene ontology (GO) assay analyses demonstrate the molecular mechanism of the antibacterial effect of QA NPs. Regarding cellular component ontology, “cell wall organization or biogenesis” (GO: 0071554) and “cell wall macromolecule metabolic process” (GO: 0044036) are the most represented categories. The present study reports that transcriptome analysis of the mechanism offers novel insights into the molecular mechanism of antibacterial assays

Development of Novel Erythromycin Derivatives with Inhibitory Activity against Proliferation of Tumor Cells - Fig 1

<p>Strategy for the design of dimers of EM-A derivatives <b>1a-2b</b>.</p

<i>In vitro</i> inhibitory effects of compounds 1a-2b against the proliferation of three human cancer cell lines.

<p><i>In vitro</i> inhibitory effects of compounds 1a-2b against the proliferation of three human cancer cell lines.</p

Apoptosis and DNA fragmentation induced by compound 1b on HeLa and MCF-7 cells.

<p>(A) Cell morphology observation under a phase contrast microscopy after incubation with medium or 1.5 μM of compound <b>1b</b> for 24 h. (B) Cellular morphologic observation under a fluorescence microscopy by AO-EB staining. (C) DNA fragmentation observation. (Scale bar = 10 μm)</p

Inhibitory and apoptosis effects of compound 1b on cell proliferation in Hela and MCF-7 cells.

<p>(A) Inhibitory effects of compounds <b>1b</b>. The cells were treated with various doses of <b>1b</b> for 6, 12, 24, 36, 48, 72 h. The inhibitory ratio was measured by MTT assay. (B) Apoptosis effects of compound <b>1b</b>. The cells were cultured with 0.5, 1.5, 2.5 μM <b>1b</b> for 24 h, stained with PI at 4°C for 30 min, and measured by flow cytometry after collection. The percentage of cells in different phases of the cell cycle was represented by a bar diagram. All of the values were mean±SD of 3 separate experiments.</p

In vitro antiproliferative activities of compound 1b against six human cancer cell lines.

<p>In vitro antiproliferative activities of compound 1b against six human cancer cell lines.</p

Mitochondrial potential alternation of HeLa and MCF-7 cells by compound 1b.

<p>After treatment with 0.5, 1.5, 2.5 μM of <b>1b</b> for 24h, the cells were stained with 5g/L Rhodamine 123. Fluorescent density reflected mitochondrial transmembrane potential was determined by flow cytometric analysis. Values were mean±SD of 3 separate experiments.</p

Effect of solvents on forming poly(butyl-2-cyanoacrylate) encapsulated paeonol nanocapsules

<p>The effect of ethanol or acetone, as oil phase solvents, upon the form of paeonol-loaded poly(butyl-2-cyanoacrylate) encapsulated nanocapsules (Pae@PNCs) by interfacial spontaneously polymerization were investigated. Pae@PNCs characterizations including morphology, radius distribution, polydispersity index (PDI), particle size, zeta potential, entrapment efficiency (EE%), drug loading (DL%) and <i>in vitro</i> paeonol release kinetics were evaluated. Results show that 100% acetone have a significant effect on forming nanocapsules, which showed the smaller size (168.3 ± 6.76 nm) under scanning electron microscopy (SEM) and one radius distribution by the particle size analyser. The data showed that using 100% acetone to prepare Pae@PNCs was leading to smaller particle size and lower polydispersity index (PDI), higher zeta potential, better EE (%) and perfect DL (%), which is linear decrease in radius (<i>r</i>² = 0.939) and PDI (<i>r</i>² = 0.974) and linear increase EE% (<i>r</i>² = 0.9879) and DL% (<i>r</i>² = 0.9892) with the acetone concentration (range 10–100% v/v). Paeonol encapsulated into and adhered on PNCs were confirmed by UV–Visible spectra (UV–Vis), Fourier transform infrared spectroscopy (FTIR) and Differential scanning calorimetry (DSC). Drug release behavior <i>in vitro</i> showed that 100% acetone as solvents on developing Pae@PNCs have greater advantages in controlling and prolonging paeonol release. Results demonstrated that solvents have a significant influence on forming Pae@PNCs.</p

Breaking the Transverse Magnetic-Polarized Light Extraction Bottleneck of Ultraviolet‑C Light-Emitting Diodes Using Nanopatterned Substrates and an Inclined Reflector

AlGaN-based light-emitting diodes (LEDs) operating in the deep-ultraviolet (UV-C) spectral range (210–280 nm) exhibit extremely low external quantum efficiency, primarily due to the presence of large threading dislocations and extremely low transverse magnetic (TM) light extraction efficiency. Here, we have demonstrated that such critical issues can be potentially addressed by using AlGaN quantum-well heterostructures grown on a hexagonal nanopatterned sapphire substrate (NPSS) and a flip-chip-bonded inclined Al mirror. Our finite-difference time domain-based numerical analysis confirms that the maximum achievable efficiency is limited by the poor light extraction efficiency due to the extremely low TM-polarized emission. In our experiment, with the usage of a meticulously designed hexagonal NPSS and an inclined Al side wall mirror (>90% reflective in the UV-C wavelength), the AlGaN quantum-well UV-C LEDs showed nearly 20% improvement in the light output power and efficiency compared to the conventional flat flip-chip LEDs. The UV-C LEDs operating at ∼275 nm exhibit a maximum output power of ∼25 mW at 150 mA, a peak external quantum efficiency of ∼4.7%, and a wall plug efficiency of ∼3.25% at 15 mA under continuous wave (CW) conditions. The presented approach opens up new opportunities to increase the extraction of UV light in the challenging spectral range by using properly designed patterned substrates and an engineered Al reflector

Breaking the Transverse Magnetic-Polarized Light Extraction Bottleneck of Ultraviolet‑C Light-Emitting Diodes Using Nanopatterned Substrates and an Inclined Reflector

AlGaN-based light-emitting diodes (LEDs) operating in the deep-ultraviolet (UV-C) spectral range (210–280 nm) exhibit extremely low external quantum efficiency, primarily due to the presence of large threading dislocations and extremely low transverse magnetic (TM) light extraction efficiency. Here, we have demonstrated that such critical issues can be potentially addressed by using AlGaN quantum-well heterostructures grown on a hexagonal nanopatterned sapphire substrate (NPSS) and a flip-chip-bonded inclined Al mirror. Our finite-difference time domain-based numerical analysis confirms that the maximum achievable efficiency is limited by the poor light extraction efficiency due to the extremely low TM-polarized emission. In our experiment, with the usage of a meticulously designed hexagonal NPSS and an inclined Al side wall mirror (>90% reflective in the UV-C wavelength), the AlGaN quantum-well UV-C LEDs showed nearly 20% improvement in the light output power and efficiency compared to the conventional flat flip-chip LEDs. The UV-C LEDs operating at ∼275 nm exhibit a maximum output power of ∼25 mW at 150 mA, a peak external quantum efficiency of ∼4.7%, and a wall plug efficiency of ∼3.25% at 15 mA under continuous wave (CW) conditions. The presented approach opens up new opportunities to increase the extraction of UV light in the challenging spectral range by using properly designed patterned substrates and an engineered Al reflector