Rapid mineralization of methyl orange by nanocrystalline-assembled mesoporous Cu2O microspheres.

In this study, nanocrystalline-assembled mesoporous Cu2O microspheres (MCMs) with enhanced visible-light driven photocatalytic activity were synthesized by a facile one-step hydrothermal method. MCMs exhibit excellent visible-light driven photocatalytic activity with 85% removal of methyl orange (MO) (60% removal of total organic carbon (TOC)) in 40 min. The excellent photocatalytic performance is dependent on the specific morphology and excellent visible-light absorption ability. Interestingly, MCMs can efficiently remove MO with or without light. The amount and categories of active species were determined by electron paramagnetic resonance and photoluminance (PL). Reactive oxygen species (ROS) (mainly ·[Formula: see text] and H2O2) and Cu (I) radicals are important in fading and further mineralization of MO. With the assistance of gas chromatography-mass spectrometer , TOC and x-ray photoelectron spectroscopy, the degradation pathways in light and dark conditions were analyzed. It has been proven that MO could be efficiently mineralized by ROS generated in light, while reaction in dark condition was more likely to be an efficient fading process.

Synthesis and Biological Evaluation of Azamacrolide Comprising the Triazole Moiety as Quorum Sensing Inhibitors.

Novel azamacrolides comprising the triazole moiety were synthesized and evaluated for their quorum sensing inhibitor activities on the Agrobacterium tumefaciens. It was found that the inhibition rate of compound Z12-3 at 200 mg/L (0.45 mM) can reach 67%. The potential binding modes between these molecules and the TraR QS receptor was performed by molecular docking. The results showed that the two nitrogen atoms in the triazole ring of Z12-3 formed hydrogen bonds with GLN-2, and the carbonyl group (C=O) in the amide formed hydrogen bonds with water. It was worth noting that the carbonyl group on the macrolides formed hydrogen bonds with the G-106 base in the DNA. These azamacrolides may block quorum sensing expression through key amino acid residues or DNA bases in the TraR QS receptor by hydrogen-bonded.

Biomaterials based on advanced oxidation processes in tooth whitening: fundamentals, progress, and models.

The increasing desire for aesthetically pleasing teeth has resulted in the widespread use of tooth whitening treatments. Clinical tooth whitening products currently rely on hydrogen peroxide formulations to degrade dental pigments through oxidative processes. However, they usually cause side effects such as tooth sensitivity and gingival irritation due to the use of high concentrations of hydrogen peroxide or long-time contact. In recent years, various novel materials and reaction patterns have been developed to tackle the issues related to H2O2-based tooth whitening. These can be broadly classified as advanced oxidation processes (AOPs). AOPs generate free radicals that have potent oxidizing properties, which can thereby increase the oxidation power and/or reduce the exposure time and can probably minimize the side effects of tooth bleaching. While there have been several reviews on clinical tooth whitening and the application of novel nanomaterials, a review based on the concept of AOPs in tooth bleaching application has not yet been conducted. This review describes the common types and mechanisms of AOPs, summarizes the latest research progress of new tooth bleaching materials based on AOPs, and proposes a model for tooth bleaching and a rate control step at the molecular level. The paper also reviews the shortcomings and suggests future development directions.

Nanoelectrochemistry monitoring of intracellular reactive oxygen and nitrogen species induced by nanoplastic exposure.

Airborne nanoplastics can enter alveolar cells and trigger intracellular oxidative stress primarily. Herein, taking advantage of the high electrochemical resolution of SiC@Pt nanoelectrodes, we achieved the quantitative discrimination of the major ROS/RNS within A549 cells, disclosed the sources of their precursors, and observed that the NO (RNS precursor) level significantly increased, whereas O2˙- (ROS precursor) remained relatively stable during the nanoplastics exposure. This establishes that iNOS or mitochondrion-targeted treatment may be a preventive or therapeutic strategy for nanoplastic-induced lung injury.

Comparison of the efficacy and safety of transurethral laser versus open prostatectomy for patients with large-sized benign prostatic hyperplasia: A meta-analysis of comparative trials.

PURPOSE: The selection of open prostatectomy (OP) over transurethral laser surgery is controversial for large volume prostates. Thus, we aim to compare the efficacy and safety of transurethral laser versus OP, and provide the latest evidence of clinical practice for large-sized benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: This meta-analysis used Review Manager V5.3 software and the systematic literature search of Cochrane Library, Embase, PubMed, and Web of Science datasets was performed for citations published from 2000 to 2020 that compared transurethral laser with OP for the treatment of large BPH. Variables of interest assessing the two techniques included clinical characteristics, and the perioperation-, effectiveness-, and complication-related outcomes. RESULTS: The meta-analysis included twelve studies containing 1,514 patients, with 792 laser and 722 OP. The transurethral laser group was associated with shorter hospital stay and catheterization duration, and less hemoglobin decreased in the perioperative variables. There was no significant difference in the international prostate symptom score, post-void residual urine volume, maximum flow rate, and quality of life score. Transurethral laser group had a significantly lower incidence of blood transfusion than OP group (odds ratio, 0.10; 95% confidence interval, 0.05 to 0.19; p<0.001; I²=8%), and no statistical differences were found with respect to the other complications. CONCLUSIONS: Both OP and transurethral laser prostatectomy are effective and safe treatments for large prostate adenomas. With these advantages of less blood loss and transfusion, and shorter catheterization time and hospital stay, laser may be a better choice for large BPH.

MoS2 Membranes for Organic Solvent Nanofiltration: Stability and Structural Control.

This paper reveals the chemical, structural, and separation stability of stacked molybdenum disulfide (MoS2) membranes and establishes a low-cost and facile approach to developing stable, selective membranes for efficient molecular separation in an organic solvent. MoS2 nanoflakes that were dominant  by monolayer MoS2 sheets as prepared via direct chemical exfoliation (chem-MoS2) were found to be chemically and structurally instable, with a sharp decrease in the level of solute rejection within a few days. Few-layer MoS2 nanoflakes were then fabricated using a hydrothermal method (hydro-MoS2). A "supportive" drying process involving glycerol pretreatment and drying in an oven was established to allow realignment of nanoflakes and adjustment of interflake spacing. We have shown that the hydro-MoS2 membranes provide a mean interflake free spacing of ∼1 nm, which is ideal for the separation of a model solute (Rose Bengal, size of ∼1.45 nm) from the solvent isopropanol (size of 0.58 nm) with good long-term stability over a 7 day test.