All-solid-state WO3/TQDs/In2S3 Z-scheme heterojunctions bridged by Ti3C2 quantum dots for efficient removal of hexavalent chromium and bisphenol A.

Ti3C2 quantum dots (TQDs) derived from ultrathin few-layered Ti3C2 nanosheets were served as the low-cost solid electron mediator of photogenerated carriers at the semiconductor interfaces, which could greatly reserve the reductive and oxidative reaction sites on the surface of heterojunctions and accelerate the reduction and oxidation reactions. The all-solid-state TQDs-bridge WO3/TQDs/In2S3 Z-scheme photocatalysts exhibited extremely promoted photocatalytic reduction of Cr (VI) and photocatalytic oxidation of Bisphenol A (BPA) under visible light irradiation, which are 4 and 3 times higher than that of WO3/In2S3 heterojunctions, respectively. The favorable photocatalytic activities of WO3/TQDs/In2S3 should attribute to the effective electron transfer and charges separation with introduction of TQDs as the electron mediators in the Z-scheme system. In addition, the stability of WO3/TQDs/In2S3 was investigated and the possible mechanisms during photo-reduction of Cr (VI) and photo-oxidation of BPA were proposed. This work provides a new strategy for fabrication of all-solid-state Z-scheme heterojunctions using Ti3C2 quantum dots as the low-cost solid electron mediator for efficient environmental remediation.

Efficacy of progesterone on threatened miscarriage: an updated meta-analysis of randomized trials.

PURPOSE: The efficacy of progesterone supplementation in the treatment of threatened miscarriage is controversial. This meta-analysis was to evaluate the correlation between progesterone and improving pregnancy outcomes in women with threatened miscarriage. METHODS: We searched PubMed, EMBASE, and the Cochrane Library for relevant randomized controlled trials (RCTs) to demonstrate the efficacy of progesterone on the threatened miscarriage pregnancy. The outcomes were miscarriage, preterm birth, and live birth. RESULTS: Nine RCTs comparing 4907 patients were included in this study. Compared with placebo or no treatment, progesterone supplementation had a relationship with a reduction in the rate of miscarriage [RR 0.70 95% Cl (0.52, 0.94)]. There was no significant difference between progesterone supplementation and placebo or no treatment in preterm birth [RR 0.87 95% Cl (0.52, 1.47) and live birth (RR 1.02 95% Cl (0.98, 1.07)]. CONCLUSION: Progesterone supplementation did not significantly improve the incidence of preterm and live birth, so progesterone treatment of threatened miscarriage may be unhelpful.

Determination of osthol and its metabolites in a phase I reaction system and the Caco-2 cell model by HPLC-UV and LC-MS/MS.

A straightforward and sensitive reversed-phase high-performance liquid chromatography (HPLC) assay was developed and validated for the analysis of osthol and its phase I metabolites (internal standard: umbelliferone). The method was validated for the determination of osthol with respect to selectivity, precision, linearity, limit of detection, recovery, and stability. The linear response range was 0.47-60 microM, and the average recoveries ranged from 98 to 101%. The inter-day and intra-day relative standard deviations were both less than 5%. Using this method, we showed that more than 80% of osthol was metabolized in 20 min in a phase I metabolic reaction system. Transport experiments in the Caco-2 cell culture model indicated that osthol was easily absorbed with high absorptive permeability (>10 x 10(-6)cm/s). The permeability did not display concentration-dependence or vectorial-dependence and is mildly temperature sensitive (activation energy less than 10 kcal/mol), indicating passive mechanism of transport. When analyzed by LC-MS/MS, five metabolites were detected in a phase I reaction system and in the receiver side of a modified Caco-2 cell model, which was supplemented with the phase I reaction system. The major metabolites appeared to be desmethyl-osthol and multiple isomers of dehydro-osthol. In conclusion, a likely cause of poor osthol bioavailability is rapid phase I metabolism via the cytochrome P450 pathways.

Application of microdialysis to study the in vivo release of pingyangmycin from in situ gels in rabbits.

Microdialysis was used together with HPLC to monitor the local concentration of pingyangmycin hydrochloride (PYM) after embolizing rabbit ear-veins with an injectable sustained release formulation, PYM-Zein/PYM-Zein-sucrose acetate isobutyrate (SAIB), in situ gel. The dialysis probe was perfused at 2 microL/min. The in vivo recovery was 46.6 3.1% (n = 4). The samples were injected directly into HPLC. PYM was detected using UV detector at 291 nm. Separation from other components in the dialysate was performed using a Discovery((R)) RP-Amide C(16) column within 12 min. The response for PYM in the dialysate was linear (r(2) > 0.996) over the range of 2.5-212 microg/mL. The limit of detection and limit of quantitation of PYM in the dialysate were 0.4 and 1.5 microg/mL, respectively. The results demonstrated that the in situ gel of PYM-Zein-SAIB could extend the release of PYM to 4 days. SAIB could significantly cut down the initial burst of PYM from the in situ gels (p < 0.05).

In vitro and in vivo characterization of huperzine a loaded microspheres made from end-group uncapped poly(d,l-lactide acid) and poly(d,l-lactide-co-glycolide acid).

The purpose of this work was to develop biodegradable microspheres for long term delivery of a potent acetyl cholinesterase inhibitor, huperzine A (Hup-A), which is of interest in the palliative treatment of Alzheimer's disease. Microspheres were successfully prepared with specifically end-group uncapped poly(d,l-lactide acid) and poly(d,l-lactide-co-glycolide acid) using a simple o/w solvent evaporation method. The morphology, particle size and size distribution, drug loading capacity, drug entrapment efficiency (EE) and in vitro drug release were studied in detail. It was found that the terminal group and the inherent viscosity (IV) of the polymers played key role in the drug encapsulation: higher EE was achieved with end-group uncapped and low IV polymers. In vitro drug release from microspheres made from the selected three kinds of polymers revealed sustained release of Hup-A without significant burst release. Preliminary pharmacokinetic study following subcutaneous injection of Hup-A loaded microspheres illustrated the sustained release of the drug over 6-8 weeks at clinically relevant doses in vivo. The studies demonstrated the feasibility of long term delivery of Hup-A using biodegradable microspheres.