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BACKGROUND: Gastroscopy procedures are frequently performed under general sedation to minimize discomfort. Patients who refuse a sedative injection may experience more discomfort and adverse reactions such as pain and nausea. These instances reduce patient compliance and willingness to participate in future procedures. Acupuncture has been shown to have an anti-nausea and analgesic effect; however, there is limited data available that demonstrates the efficacy of acupuncture when applied before gastroscopy. METHODS: A total of 60 participants will be randomly assigned to the electroacupuncture (EA) group and the sham electroacupuncture (SEA) group at a ratio of 1:1. Acupuncture treatment will be performed before gastroscopy for a duration of 30 min. All patients will complete detailed questionnaires at 30 min and 7 days post-procedure to record the severity of their symptoms. The primary outcome will be the average of 4 standard visual analogue scale (VAS) scores in the categories of nausea, vomiting, throat discomfort, and agitation as reported by the patient. The secondary outcomes will be patient's anxiety level as recorded by the 6-item short form of the State-Trait Anxiety Inventory (STAI-S6) and Amsterdam Pre-Operative Anxiety and Information Scale (APAIS), preference in a future endoscopy, pulse oxygen saturation (SpO2), heart rate (HR), and blood pressure (BP). Anxiety scales will be assessed before and after acupuncture; others will be completed at 30 min and 7 days post-procedure. The duration of the gastroscopy and the number of biopsies will be recorded after operation. DISCUSSION: This randomized controlled trial will explore the feasibility of the further clinical application of electroacupuncture for the improvement of patient discomfort during gastroscopy without systemic sedation. TRIAL REGISTRATION: ChiCTR2000040726 . This trial has been approved by the Ethics Committee of Shanghai Municipal Hospital of Traditional Chinese Medicine (2020SHL-KY-11). Registration date 12 August 2020.

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Metal-organic frameworks (MOF) are an emerging class of microporous materials with promising applications. MOF nanocrystals, and their assembled super-structures, can display unique properties and reactivities when compared with their bulk analogues. MOF nanostructures of 0-D, 2-D, and 3-D dimensions can be routinely obtained by controlling reaction conditions and ligand additives, while formation of 1-D MOF nanocrystals (nanowires and nanorods) and super-structures has been relatively rare. We report here a facile templated interfacial synthesis methodology for the preparation of a series of 1-D MOF nano- and micro-structures with precisely controlled shapes and sizes. Specifically, by applying track-etched polycarbonate (PCTE) membranes as the templates and at the oil/water interface, we rapidly and reproducibly synthesize zeolitic imidazolate framework-8 (ZIF-8) and ZIF-67 nano- and micro structures of sizes ranging from 10 nm to 20 µm. We also identify a size confinement effect on MOF crystal growth, which leads to single crystals under the most restricted conditions and inter-grown polycrystals at larger template pore sizes, as well as surface directing effects that influence the crystallographic preferred orientation. Our findings provide a potentially generalizable method for controlling the size, morphology, and crystal orientations of MOF nanomaterials, as well as offering fundamental understanding into MOF crystal growth mechanisms.

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This study reports the synthesis, characterization and environmental applications of nitrogen doped TiO2 photocatalyst in the form of powder and film. N-TiO2 photocatalysts were synthesized via the hydrolysis of titanium tetraisopropoxide using urea as the nitrogen source. The crystalline structure, particle size and specific surface area of the resultant N-TiO2 nanoparticles were investigated by x-ray powder diffraction and the Brunauer-Emmett-Teller method. The results showed that a mixture of anatase and brookite phases was formed at pH 1 after annealing the powder at 450 ° C for 4 h, in contrast to a pure anatase phase at pH 3. UV-vis spectral characterization showed that the absorption region of the as-prepared N-TiO2 was extended to the visible light region. Stable sols could be achieved by controlling the molar ratio of water-to-titanium precursor and pH of the sols. During the photocatalytic test, in comparison to the standard commercial photocatalyst Evonik-Degussa P25 and home-made bare TiO2 nanoparticles, the N-TiO2 particles exhibited enhanced photocatalytic performance for degradation of methylene blue (MB) dye. The visible light induced photocatalytic inactivation of the obtained nanopowders and nanofilms on bacteria (Escherichia coli) was evaluated. The N-TiO2 nanomaterials showed higher bactericidal activity under visible light irradiation.

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TiO2 photocatalysts have been found to kill cancer cells, bacteria and viruses under mild UV illumination, which offers numerous potential applications. On the other hand, Ag has long been proved as a good antibacterial material as well. The advantage of Ag-TiO2 nanocomposite is to expand the nanomaterial's antibacterial function to a broader range of working conditions. In this study neat TiO2 and Ag-TiO2 composite nanofilms were successfully prepared on silicon wafer via the sol-gel method by the spin-coating technique. The as-prepared composite Ag-TiO2 and TiO2 films with different silver content were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) to determine the topologies, microstructures and chemical compositions, respectively. It was found that the silver nanoparticles were uniformly distributed and strongly attached to the mesoporous TiO2 matrix. The morphology of the composite film could be controlled by simply tuning the molar ratio of the silver nitrate aqueous solution. XPS results confirmed that the Ag was in the Ag(0) state. The antimicrobial effect of the synthesized nanofilms was carried out against gram-negative bacteria (Escherichia coli ATCC 29425) by using an 8 W UV lamp with a constant relative intensity of 0.6 mW cm(-2) and in the dark respectively. The synthesized Ag-TiO2 thin films showed enhanced bactericidal activities compared to the neat TiO2 nanofilm both in the dark and under UV illumination.

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Low molecular mass organic gelator (LMOG) as an important component of liquid crystal physical gel has a great influence on the electro-optical properties. In this paper, three analogues of amide gelator were synthesized and employed as LMOGs in nematic liquid crystal 5CB. Both hydrogen-bonding and pi-pi-stacking interactions in the gel phase were found to stabilize the self-assembled structure. It was observed that the morphology was highly dependent on the crystallinity of gelators, which was affected by the intensity of hydrogen bonding. The thicker fibril was obtained with higher crystallinity of LMOG, while the thinner fibril was obtained with lower crystallinity. Moreover, the electro-optical properties of liquid crystal physical gels were proposed to be related to the interaction between the fibrils and the liquid crystal molecules.

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In this paper, chitosan porous beads were prepared by using a phase inversion technique, and then used for the adsorption and removal of copper(II) ions. The porosity, diameter and other characteristics were characterized. With the increase of chitosan and NaOH concentration used to prepare the beads, the amount of adsorbed Cu2+ per gram of the beads decreased. A maximum adsorption amount was observed at a pH value of 6.0 for the cross-linked porous chitosan beads. The amount of the adsorbed Cu2+ increased with the Cu2+ concentration used in the adsorption experiments. By the relationship of the ratio of the equilibrium Cu2+ concentration in the solution (C(e)) to the adsorbed equilibrium amount (P(e)) (C(e)/P(e)) and C(e), we concluded that the adsorption of Cu2+ to the porous chitosan beads was Langmuir adsorption. The Cu2+-loaded porous chitosan beads were stable in water, which is useful for further study on selectively adsorption of IgG. The results suggested that the porous chitosan beads were useful adsorbents for copper ions removal in water treatment, and the Cu2+-loaded beads may be good sorbents for IgG removal in blood purification.

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