Highly selective Cu2+ detection with a naphthalimide-functionalised pillar[5]arene fluorescent chemosensor.

Ligand 1, a rim-differentiated pillar[5]arene macrocycle modified with five naphthalimide groups through click chemistry, serves as an effective ratiometric fluorescent chemosensor for Cu2+. In contrast to the monomeric naphthalimide control compound 2, which shows only monomer emission, ligand 1 demonstrates dual emission characteristics encompassing both the monomer and excimer of the naphthalimide moieties. The binding properties of ligand 1 toward 15 different metal ions were systematically investigated in CH2Cl2/CH3CN (v/v, 1 : 1) by UV-vis and fluorescence spectroscopy. Remarkably, ligand 1 exhibits exceptional selectivity for Cu2+ ions. Upon complexation with Cu2+, the excimer emission of ligand 1 diminishes, concomitant with an enhancement of its monomer emission. The binding ratio for 1·Cu2+ was determined to be 1 : 1, with an association constant of (3.39 ± 0.40) × 105 M-1 calculated using a nonlinear least-squares curve-fitting method. Furthermore, the limit of detection (LOD) was found to be 185 ± 7 nM. Our results from 1H NMR titration, high-resolution mass spectrometry analysis and density functional theory calculations of 1·Cu2+ suggest synergistic coordination between Cu2+ and the triazole groups on ligand 1.

Synthesis of n-butyl acetate via reactive distillation column using Candida Antarctica lipase as catalyst.

The reactive distillation process for the synthesis of n-butyl acetate via transesterification of ethyl acetate with n-butyl alcohol catalyzed by immobilized lipase was simulated and experimentally tested in this work. Based on the reaction kinetics, a reactive distillation process model was developed. The effects of theoretical stages number in the reaction section, the rectifying section and stripping section, reflux ratio, feed molar ratio and relative feed position on the transesterification distillation process were investigated. The transesterification of ethyl acetate with n-butyl alcohol was carried out in a small-scale reactive distillation column. The results showed that the optimal operating conditions are as follows: reaction section stages were 13, rectifying section stages were six, stripping section stages were five, reflux ratio was 1, mole ratio of ethyl acetate and n-butanol was 3:1, the feeding positions of n-butanol and ethyl acetate were at the top and bottom of the reaction section, respectively. Compared to the batch reaction with only 60% conversion of n-butanol, the reactive distillation column can improve the conversion of n-butanol (up to 93.6%).At the same time, the experiment verified that the conversion of n-butanol could still reach 72.5%, after the lipase-loaded packing storage in the reaction system at 70 °C for 120 days.

Effect of Yiqi Buxue Decoction on Hemodynamic Changes of the Uterine Artery and Fetal Umbilical Artery and Pregnancy Outcomes in Pregnant Patients with Pulmonary Arterial Hypertension.

OBJECTIVE: To explore the effect of Yiqi Buxue decoction on hemodynamic changes of the uterine artery and fetal umbilical artery and pregnancy outcomes in pregnant patients with pulmonary arterial hypertension (PAH). METHODS: 120 pregnant patients with PAH treated in our hospital (January 2019-January 2020) were chosen as the research objects, and randomly split into group A (n = 60) and group B (n = 60). Both groups received routine treatment, and group B was treated with sildenafil citrate, while group A was treated with Yiqi Buxue decoction combined with sildenafil citrate. Both groups received 6 weeks of treatment to analyze the hemodynamic changes of the uterine artery and fetal umbilical artery and compare the cardiopulmonary function indexes and pregnancy outcomes between the two groups. RESULTS: The hemodynamic indexes of the uterine artery and fetal umbilical artery, cardiopulmonary function indexes, and pregnancy outcomes in group A after treatment were notably better compared with group B (P < 0.01). CONCLUSION: Yiqi Buxue decoction can stabilize the hemodynamics of pregnant patients with PAH, improve their cardiopulmonary function, alleviate hypotension, and thus, reduce the possibility of adverse pregnancy outcomes, which should be popularized in practice.

Rim-differentiated Co-pillar[4+1]arenes.

A series of rim-differentiated Co-pillar[4+1]arenes featuring penta-substituted "upper" rims and mono-functionalisable "lower" rims was successfully synthesised and fully characterised. These novel pillar[5]arene-based scaffolds with clickable moieties and extra synthetic handles are versatile platforms for self-assembled molecular architectures and biological applications.

Schisandrin B synergizes docetaxel-induced restriction of growth and invasion of cervical cancer cells in vitro and in vivo.

BACKGROUND: Cervical cancer is a prevalent tumor in women. Here we investigated the synergic effects of Schisandrin B (Sch B), an active compound extracted from the Chinese herb Schisandra Chinensis, in docetaxel (DTX)-induced restriction of growth and invasion of cervical cancer. METHODS: Caski cells were treated with Sch B and DTX for 24 hours. In vitro effects were investigated with Cell counting kit-8, western blotting, colony-forming, Transwell, Annexin V-FITC enabled flow cytometry. Then, in vivo experiments were engaged with Sch B (20 mg/kg) and DTX (10 mg/kg) for 30 days, and IHC were applied to validate the effects in vivo. RESULTS: Both Sch B and DTX reduced cell viability, inhibited colony formatting, induced apoptosis, and limited cell invasion. Co-administration of Sch B and DTX more significantly enhanced these changes. The relative levels of HPV infection and tumor progression related proteins p-AKT/AKT, NF-kappaB, Cyclin D1, CDK-4, MMP-9, Notch1, ß-catenin and p-p38/p38 were markedly inactivated. The effects of Sch B in cervical cancer were further confirmed in Caski cell-xenograft BALB/c nude mice. Co-administration of Sch B enhanced the anti-tumor effects of DTX in vivo, inhibited tumor formation, increased apoptotic cells, and reduced Ki67 and N-cadherin expression. CONCLUSIONS: Altogether, Sch B enhanced the anti-tumor effects of DTX in vitro and in vivo via growth, invasion, and apoptosis regulating. The results supported therapies of co-administering Sch B and DTX to be developed in cervical cancer.

Co-immobilization of metal and enzyme into hydrophobic nanopores for highly improved chemoenzymatic asymmetric synthesis.

Chemoenzymatic catalysts with hydrophobic nanopores were fabricated by co-immobilizing metal nanoparticles and enzymes into the dendritic organosilica nanoparticles. They demonstrated highly improved catalytic performance in chemoenzymatic asymmetric synthesis of chiral amines and alcohols. The hydrophobic microenvironment proved to be critical to enhanced stability, activity and cascade efficiency.

Green synthesis of benzonitrile using ionic liquid with multiple roles as the recycling agent.

Preparation of benzonitrile from benzaldehyde and hydroxylamine hydrochloride is one of the most advantageous approaches. Nevertheless, it suffers from various constraints such as longer reaction time, corrosion and recovery of hydrochloric acid, the use of metal salt catalysts and their separation. For these reasons, a novel green benzonitrile synthetic route was proposed with ionic liquid as the recycling agent in this study. The results indicated that hydroxylamine 1-sulfobutyl pyridine hydrosulfate salt ((NH2OH)2·[HSO3-b-Py]·HSO4) was an expert alternative to hydroxylamine hydrochloride. Meanwhile, the ionic liquid [HSO3-b-Py]·HSO4 exhibited the multiple roles of co-solvent, catalysis and phase separation, thus the use of metal salt catalyst was eliminated, and no additional catalyst was needed. Hence, the separation process was greatly simplified. When the molar ratio of benzaldehyde to (NH2OH)2·[HSO3-b-Py]·HSO4 was 1 : 1.5, the volume ratio of paraxylene to [HSO3-b-Py]·HSO4 was 2 : 1, the benzaldehyde conversion and benzonitrile yield were both 100% at 120 °C in 2 h. Even better, the ionic liquid could be recovered easily by phase separation, and recycled directly after reaction. Additionally, this novel route is applicable to the green synthesis of a variety of aromatic, heteroaromatic and aliphatic nitriles with excellent yields.

[Preliminary report on primary drilling procedure at the time of hydroxyapatite orbital implant].

OBJECTIVE: To evaluate the clinical effect of the drilling and inserting a motility peg at the time of hydroxyapatite orbital implant. METHODS: After drilling and insertion of a titanium motility peg, a hydroxyapatite orbital implant was inserted in 31 consecutive patients. Of the 31 patients, 23 had been referred for primary enucleation and 8 for secondary implant surgery. The titanium-threaded sleeve was driven into the hydroxyapatite after which the titanium flat-headed peg was inserted into the sleeve before orbital implantation. The flat-headed peg was replaced with a titanium motility/support peg 3 to 7 months later. RESULTS: Follow-up ranged from 3.0 to 11.0 months (mean, 6.9 months). All patients were successfully fit with prostheses. Prosthetic motility was acceptable in each patient. 12 of 31 titanium flat-headed pegs became spontaneously and partially exposed within 3 to 7 months. There were no cases of secondary infection, implant exposure or extrusion of the motility peg. CONCLUSION: The hydroxyapatite orbital implant primary drilling procedure gives good cosmetic results with good motility of the artificial eye. It does not result in increased complications, and is an effective and efficient surgical option.

Seismic analysis for translational failure of landfills with retaining walls.

In the seismic impact zone, seismic force can be a major triggering mechanism for translational failures of landfills. The scope of this paper is to develop a three-part wedge method for seismic analysis of translational failures of landfills with retaining walls. The approximate solution of the factor of safety can be calculated. Unlike previous conventional limit equilibrium methods, the new method is capable of revealing the effects of both the solid waste shear strength and the retaining wall on the translational failures of landfills during earthquake. Parameter studies of the developed method show that the factor of safety decreases with the increase of the seismic coefficient, while it increases quickly with the increase of the minimum friction angle beneath waste mass for various horizontal seismic coefficients. Increasing the minimum friction angle beneath the waste mass appears to be more effective than any other parameters for increasing the factor of safety under the considered condition. Thus, selecting liner materials with higher friction angle will considerably reduce the potential for translational failures of landfills during earthquake. The factor of safety gradually increases with the increase of the height of retaining wall for various horizontal seismic coefficients. A higher retaining wall is beneficial to the seismic stability of the landfill. Simply ignoring the retaining wall will lead to serious underestimation of the factor of safety. Besides, the approximate solution of the yield acceleration coefficient of the landfill is also presented based on the calculated method.