Au@h-Al2O3 Analogic Yolk–Shell Nanocatalyst for Highly Selective Synthesis of Biomass-Derived D-xylonic Acid via Regulation of Structure Effects

Selective oxidation of biomass-based monosaccharides into value-added sugar acids is highly desired, but limited success of producing D-xylonic acid has been achieved. Herein, we report an efficient catalyst system, viz., Au nanoparticles anchored on the inner walls of hollow Al2O3 nanospheres (Au@h- Al2O3), which could catalyze the selective oxidation of D-xylose into D-xylonic acid under base-free conditions. The mesoporous Al2O3 shell as the adsorbent first adsorbed D-xylose. Then, the interface of Au nanoparticles and Al2O3 as active sites spontaneously dissociated O2, and the exposed Au nanoparticle surface as the catalytic site drove the transformation. With this catalyst system, the valuable D-xylonic acid was produced with excellent yields in the aerobic oxidation of D-xylose. Extensive investigation showed that Au@h- Al2O3 is an efficient catalyst with high stability and recyclability

Post-traumatic right carotid-cavernous fistula resulting in symptoms in the contralateral eye: a case report and literature review

Abstract Background To report a case of a carotid-cavernous fistula (CCF) that occurred after a motor vehicle accident and review the uniqueness of this case and the main confusing points for the diagnosis of such cases. Case presentation A 22-year-old man complained of left eyelid swelling, eye redness, visual decrease and occasional headache after motor vehicle accident 4 months prior during which he experienced a head injury. He was initially thought to have glaucoma, but he was finally diagnosed with a right CCF based on magnetic resonance imaging (MRI) and digital subtraction angiography (DSA). Timely embolization surgery resulted in obvious relief of the ocular symptoms and an improved prognosis. Conclusion This is the first reported case of a post-traumatic unilateral CCF with contralateral symptoms in direct CCF, it is very infrequent and deserves our attention. We should maintain high suspicion of CCF and confirm the diagnosis by DSA when managing such patients to prevent serious consequences. Early diagnosis and treatment can improve the prognosis of patients

Microwave-assisted Extraction of Polysaccharides from Bamboo (Phyllostachys acuta) Leaves and their Antioxidant Activity

Polysaccharides were isolated from Phyllostachys acuta leaves by microwave-assisted extraction under various temperatures and time. The obtained polysaccharides were characterized by acid hydrolysis, the Folin-Ciocalteu method, and Fourier transform infrared spectroscopy (FTIR). The major monosaccharides presented in the extracts were arabinose (258.0 mg/g to 414.5 mg/g), galactose (167.0 mg/g to 289.2 mg/g), and glucose (157.4 mg/g to 246.7 mg/g) along with some mannose, fructose, and xylose. The total phenol yield of the bamboo leaves was 0.31 mg/g to 0.73 mg/g. The FTIR spectra revealed that the polysaccharides mostly consisted of β-glycosidic linkages. For the cytotoxicity, the presence of polysaccharides considerably elevated the multiplication of HepG2 cells and showed no growth inhibition for the samples. For the antioxidant activities, the polysaccharides exhibited excellent abilities both in the diphenyl picrylhydrazyl radical potential (DPPH) assay and ferric reducing antioxidant potential (FRAP) assay. The results suggest that bamboo leaf polysaccharides have great potential to be applied in the food, healthcare, and pharmaceutical fields

Xylan-Derived Light Conversion Nanocomposite Film

A new type of sustainable light conversion nanocomposite film was fabricated by using carboxymethyl xylan as matrix and xylan-derived carbon dots (CDs) as both light conversion regents and nano reinforcements. The results demonstrate that CDs can not only significantly enhance the mechanical strength of the nanocomposite film because of chemical reaction between CDs and carboxymethyl xylan, but also impart the film with excellent optical properties. With 1.92 wt% CDs, the tensile strength and elastic modulus of the film are increased by 114.3% and 90.7%, respectively. Moreover, the film has typical excitation and emission spectra, enabling the efficient absorption of UV and the conversion of UV to blue light. This xylan-derived light conversion nanocomposite film is expected to be used in agricultural planting and food packaging

Lignin Nanosphere-Supported Cuprous Oxide as an Efficient Catalyst for Huisgen [3+2] Cycloadditions under Relatively Mild Conditions

In this work, low-cost lignin nanospheres were fabricated and further applied as an efficient and sustainable support for preparing cuprous oxide (Cu2O) “green” catalyst by using electrospraying technology. The unalloyed lignin, a special three-dimensional molecular structure, was successfully processed into uniform nanospheres under an electrospraying condition. The synthesized lignin-supported Cu2O catalyst had a well-defined nanosphere structure, and Cu2O nanoparticles with sizes less than 30 nm were supported by exposed layers of lignin nanospheres. There were C–O–Cu bonds formed between the lignin nanospheres and the metallic nanoparticles. The lignin nanospheres and the lignin nanosphere-supported catalyst werfe characterized by utilizing XRD, SEM, TEM, XPS, EDS, and TGA. The immobilization of Cu2O nanoparticles on the lignin nanospheres was beneficial for dispersion of the Cu2O nanoparticles and preventing their aggregation, which could cause catalyst deactivation, which favored the Huisgen [3+2] cycloaddition reaction. The triazole synthesis results indicated that the lignin nanosphere-supported Cu2O catalyst had a high catalytic performance with 99% yield under solvent-free conditions. Furthermore, the as-synthesized catalyst could be recycled for four times without significantly losing its catalytic activity

Novel hydrophobic hemicelluloses: Synthesis and characteristic

Novel hydrophobic hemicelluloses possessing hydrophobic groups were prepared by the benzylation of wheat straw hemicelluloses with benzyl chloride under the presence of catalyst in an ethanol/water system. In particular, the progress of the benzylation reaction was studied as a function of the volume ratio of ethanol/water from 4:1 to 6:4, the molar ratio of NaOH/anhydroxylose unit in hemicelluloses from 0.6:1 to 1.5:1, the molar ratio of benzyl chloride/anhydroxylose unit in hemicelluloses from 0.5:1 to 2.0:1, reaction temperature 50-80 degrees C, and reaction time 4-20h. Benzylated hemicelluloses with the low degree of substitution from 0.09 to 0.35 were obtained depending on the experimental conditions. The incorporation of benzyl groups into the backbone of hemicelluloses was confirmed by FT-IR and C-13 NMR spectroscopies. The thermal stability increased after the modification of hemicelluloses due to the introduction of benzyl groups. The introduction of benzyl groups endows hemicelluloses with the hydrophobicity, which could be potentially applied in plastic industries. (C) 2012 Elsevier Ltd. All rights reserved

Multiresponsive Hydrogels Based on Xylan-Type Hemicelluloses and Photoisomerized Azobenzene Copolymer as Drug Delivery Carrier

Stimulus-responsive hydrogels, which can undergo significant physicochemical changes in response to various physical or chemical stimuli, have drawn wide attention in many fields. In this study, novel photoresponsive hydrogels prepared by free radical copolymerization of xylan-type hemicellulose methacrylate with 4-[(4-acryloyloxyphenyl)­azo]­benzoic acid (AOPAB) were investigated, which showed multiresponsive behaviors to pH, water/ethanol alternating solutions, and light. The swelling ratios of the prepared hydrogels in distilled water decreased from 9.8 to 2.2 g/g with AOPAB content increase from 2% to 16%. The hydrogel displayed rapid swelling and deswelling performance in water and ethanol alternating solutions. Additionally, under UV irradiation the <i>trans</i>-conformation of azobenzene in the hydrogel would generally convert into the <i>cis</i>-conformation and resulted in the hydrophilic/hydrophobic balance variation of the hydrogel. Therefore, the hydrogel loaded with vitamin B₁₂ (VB₁₂) showed a higher drug cumulative release rate under UV irradiation than that without UV irradiation

The Association Between Phosphodiesterase Type 5 Inhibitor Use and Risk of Non-Arteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis

Introduction: Phosphodiesterase type 5 inhibitors (PDE5-Is) are first-line drugs for erectile dysfunction. Non-arteritic anterior ischemic optic neuropathy (NAION) has been linked with PDE5-I use. However, no meta-analysis or conclusive review has explored the association between NAION and PDE5-I use. Aim: To investigate the association between PDE5-I use and risk of NAION. Methods: A comprehensive literature search was conducted using online databases in October 2017 to obtain studies researching the association between PDE5-I application and occurrence of NAION. Summarized unadjusted risk ratios (RRs) with 95% CIs were calculated for the strength of this association. This study was conducted in accordance to Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and registered in PROSPERO under number CRD42017080865. Main Outcome Measures: The strength of association between PDE5-I use and risk of NAION was assessed through pooled unadjusted RRs and 95% CIs. Results: 5 original articles with 6 clinical observations were included in the meta-analysis. No significant higher risk of NAION was observed after the use of PDE5-Is within a 1-month period (RR = 1.16, 95% CI = 0.98-1.39, P = .09). Subgroup analyses indicated 2 PDE5-Is were significantly related to NAION (tadalafil: RR = 2.14, 95% CI = 1.20–3.84, P = .01; sildenafil: RR = 2.25, 95% CI = 1.29–3.94, P = .004). Conclusions: Although we found no association between NAION and PDE5-I use, our results should be interpreted cautiously because we included only observational studies and could not control for potential confounders. Because NAION is a rare ocular disease and difficult to diagnose, this association should be confirmed in prospective comparative studies with larger samples and more rigorous designs.Liu B, Zhu L, Zhong J, et al. The Association Between Phosphodiesterase Type 5 Inhibitor Use and Risk of Non-Arteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis. Sex Med 2018;6:185−192. Key Words: Association, Meta-Analysis, Non-Arteritic Anterior Ischemic Optic Neuropathy, Phosphodiesterase Type 5 Inhibitors, Systematic Revie

Biomass-Based Porous N‑Self-Doped Carbon Framework/Polyaniline Composite with Outstanding Supercapacitance

Composites combining electrostatic charge accumulation and faradic reaction mechanisms are especially attractive high-performance supercapacitor electrodes for electrochemical energy storage. Up to now, it is difficult to prepare low-cost carbon composites from renewable resources. In this work, an outstanding and low-cost composite was fabricated by using sustainable N-self-doped carbon framework as a hierarchical porous carbon substrate from renewable resource. The N-self-doped carbon framework was fabricated from chitosan via a facile yet unique self-assembly and ice template method without any physical or chemical activation, and exhibited hierarchical porous structure. This texture not only allowed the efficient infiltration and uniform coating of polyaniline (PANI) in the inner network but also permitted a rapid penetration and desorption of electrolytes. Due to short diffusion pathway, uniformly coating of PANI, and high accessibility of PANI to electrolytes, the composite electrode had a very high supercapacitance of 373 F g^–1 (1.0 A g^–1) and excellent rate capability (275 F g^–1, 10 A g^–1) in a three-electrode system. The symmetric supercapacitor also showed a supercapacitance of high up to 285 F g^–1 (0.5 A g^–1), and a very high energy density of 22.2 Wh kg^–1. Furthermore, the composite also presented a good cycling stability