Association between long-term ozone exposure and readmission for chronic obstructive pulmonary disease exacerbation.

The relationship between long-term ozone (O3) exposure and readmission for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) remains elusive. In this study, we collected individual-level information on AECOPD hospitalizations from a standardized electronic database in Guangzhou from January 1, 2014, to December 31, 2015. We calculated the annual mean O3 concentration prior to the dates of the index hospitalization for AECOPD using patients' residential addresses. Employing Cox proportional hazards models, we assessed the association between long-term O3 concentration and the risk of AECOPD readmission across several time frames (30 days, 90 days, 180 days, and 365 days). We estimated the disease and economic burden of AECOPD readmissions attributable to O3 using a counterfactual approach. Of the 4574 patients included in the study, 1398 (30.6%) were readmitted during the study period, with 262 (5.7%) readmitted within 30 days. The annual mean O3 concentration was 90.3 µg/m3 (standard deviation [SD] = 8.2 µg/m3). A 10-µg/m3 increase in long-term O3 concentration resulted in a hazard ratio (HR) for AECOPD readmission within 30 days of 1.28 (95% confidence interval [CI], 1.09 to 1.49), with similar results for readmission within 90, 180, and 365 days. Older patients (aged 75 years or above) and males were more susceptible (HR, 1.33; 95% CI, 1.10-1.61 and HR, 1.29; 95% CI, 1.09-1.53, respectively). The population attributable fraction for 30-day readmission due to O3 exposure was 29.0% (95% CI, 28.4%-30.0%), and the attributable mean cost per participant was 362.3 USD (354.5-370.2). Long-term exposure to elevated O3 concentrations is associated with an increased risk of AECOPD readmission, contributing to a significant disease and economic burden.

Comparison of the Partition Efficiencies of Multiple Phenolic Compounds Contained in Propolis in Different Modes of Acetonitrile⁻Water-Based Homogenous Liquid⁻Liquid Extraction.

Homogeneous liquid⁻liquid extraction (HLLE) has attracted considerable interest in the sample preparation of multi-analyte analysis. In this study, HLLEs of multiple phenolic compounds in propolis, a polyphenol-enriched resinous substance collected by honeybees, were performed for improving the understanding of the differences in partition efficiencies in four acetonitrile⁻water-based HLLE methods, including salting-out assisted liquid⁻liquid extraction (SALLE), sugaring-out assisted liquid⁻liquid extraction (SULLE), hydrophobic-solvent assisted liquid⁻liquid extraction (HSLLE), and subzero-temperature assisted liquid⁻liquid extraction (STLLE). Phenolic compounds were separated in reversed-phase HPLC, and the partition efficiencies in different experimental conditions were evaluated. Results showed that less-polar phenolic compounds (kaempferol and caffeic acid phenethyl ester) were highly efficiently partitioned into the upper acetonitrile (ACN) phase in all four HLLE methods. For more-polar phenolic compounds (caffeic acid, p-coumaric acid, isoferulic acid, dimethoxycinnamic acid, and cinnamic acid), increasing the concentration of ACN in the ACN⁻H2O mixture could dramatically improve the partition efficiency. Moreover, results indicated that NaCl-based SALLE, HSLLE, and STLLE with ACN concentrations of 50:50 (ACN:H2O, v/v) could be used for the selective extraction of low-polarity phenolic compounds. MgSO4-based SALLE in the 50:50 ACN⁻H2O mixture (ACN:H2O, v/v) and the NaCl-based SALLE, SULLE, and STLLE with ACN concentrations of 70:30 (ACN:H2O, v/v) could be used as general extraction methods for multiple phenolic compounds.

Comparison of salting-out and sugaring-out liquid-liquid extraction methods for the partition of 10-hydroxy-2-decenoic acid in royal jelly and their co-extracted protein content.

Homogeneous liquid-liquid extraction (h-LLE) has been receiving considerable attention as a sample preparation method due to its simple and fast partition of compounds with a wide range of polarities. To better understand the differences between the two h-LLE extraction approaches, salting-out assisted liquid-liquid extraction (SALLE) and sugaring-out assisted liquid-liquid extraction (SULLE), have been compared for the partition of 10-hydroxy-2-decenoic acid (10-HDA) from royal jelly, and for the co-extraction of proteins. Effects of the amount of phase partition agents and the concentration of acetonitrile (ACN) on the h-LLE were discussed. Results showed that partition efficiency of 10-HDA depends on the phase ratio in both SALLE and SULLE. Though the partition triggered by NaCl and glucose is less efficient than MgSO4 in the 50% (v/v) ACN-water mixture, their extraction yields can be improved to be similar with that in MgSO4 SALLE by increasing the initial concentration of ACN in the ACN-water mixture. The content of co-extracted protein was correlated with water concentration in the obtained upper phase. MgSO4 showed the largest protein co-extraction at the low concentration of salt. Glucose exhibited a large protein co-extraction in the high phase ratio condition. Furthermore, NaCl with high initial ACN concentration is recommended because it produced high extraction yield for 10-HDA and the lowest amount of co-extracted protein. These observations would be valuable for the sample preparation of royal jelly.

One-Step Extraction and Hydrolysis of Flavonoid Glycosides in Rape Bee Pollen Based on Soxhlet-Assisted Matrix Solid Phase Dispersion.

INTRODUCTION: Flavonoids are frequently found as glycosylated derivatives in plant materials. To determine contents of flavonoid aglycones in these matrices, procedures for the extraction and hydrolysis of flavonoid glycosides are required. The current sample preparation method is both labour and time consuming. OBJECTIVE: Develop a modified matrix solid phase dispersion (MSPD) procedure as an alternative methodology for the one-step extraction and hydrolysis of flavonoid glycosides. METHOD: HPLC-DAD was applied for demonstrating the one-step extraction and hydrolysis of flavonoids in rape bee pollen. The obtained contents of flavonoid aglycones (quercetin, kaempferol, isorhamnetin) were used for the optimisation and validation of the method. RESULTS: The extraction and hydrolysis were accomplished in one step. The procedure completes in 2 h with silica gel as dispersant, a 1:2 ratio of sample to dispersant, and 60% aqueous ethanol with 0.3 M hydrochloric acid as the extraction solution. The relative standard deviations (RSDs) of repeatability were less than 5%, and the recoveries at two fortified levels were between 88.3 and 104.8%. CONCLUSION: The proposed methodology is simple and highly efficient, with good repeatability and recovery. Compared with currently available methods, the present work has advantages of using less time and labour, higher extraction efficiency, and less consumption of the acid catalyst. This method may have applications for the one-step extraction and hydrolysis of bioactive compounds from plant materials. Copyright © 2017 John Wiley & Sons, Ltd.