Multimodal immunogenomic biomarker analysis of tumors from pediatric patients enrolled to a phase 1-2 study of single-agent atezolizumab.

We report herein an exploratory biomarker analysis of refractory tumors collected from pediatric patients before atezolizumab therapy (iMATRIX-atezolizumab, NCT02541604 ). Elevated levels of CD8+ T cells and PD-L1 were associated with progression-free survival and a diverse baseline infiltrating T-cell receptor repertoire was prognostic. Differential gene expression analysis revealed elevated expression of CALCA (preprocalcitonin) and CCDC183 (highly expressed in testes) in patients who experienced clinical activity, suggesting that tumor neoantigens from these genes may contribute to immune response. In patients who experienced partial response or stable disease, elevated Igα2 expression correlated with T- and B-cell infiltration, suggesting that tertiary lymphoid structures existed in these patients' tumors. Consensus gene co-expression network analysis identified core cellular pathways that may play a role in antitumor immunity. Our study uncovers features associated with response to immune-checkpoint inhibition in pediatric patients with cancer and provides biological and translational insights to guide prospective biomarker profiling in future clinical trials.

Therapeutic plasma exchange in patients with sepsis: Secondary analysis of a cluster-randomized controlled trial.

INTRODUCTION: Sepsis is life-threatening organ dysfunction caused by infection-related inflammatory response. Therapeutic plasma exchange (TPE) can remove inflammatory mediators and benefit patients in different disease settings. However, no solid evidence showed the efficacy and safety of TPE in sepsis. METHODS: This study was a secondary analysis of a randomized controlled trial. Critically ill patients with sepsis were divided into two groups according to whether treated with TPE. The primary outcome was the delta Sequential Organ Failure Assessment (SOFA) score from days 1 to 7. Secondary outcomes included new-onset organ failure, intensive care unit (ICU)-free and alive days to day 28, and 28-day mortality. Propensity score-matched (PSM) analysis was applied to control confounders. Analysis of covariance (ANCOVA) and logistic regression were used to assess the association between TPE and selected outcomes. RESULTS: Among the 2772 critically ill patients enrolled in the trial, 742 patients with sepsis were selected and 22 patients received TPE were matched with 22 control patients. No significant difference was found in the delta SOFA score and 28-day mortality between TPE group and control group. The ICU-free and alive days in the TPE group were significantly shorter than the control group. CONCLUSIONS: TPE may be not associated with improvement of organ failure and mortality in critically ill patients with sepsis and may be associated with a prolonged ICU stay.

Dispersive liquid-liquid microextraction combined with gas chromatography-electron capture detection for the determination of polychlorinated biphenyls in soils.

In this article, dispersive liquid-liquid microextraction (DLLME) and gas chromatography-electron capture detection (GC-ECD) were presented for the extraction and determination of five polychlorinated biphenyls (PCBs) in soil samples. Acetone was used as extraction solvent for the extraction of PCBs from soil samples. In DLLME, the target analytes in the extraction solvent were rapidly transferred from the acetone extract to chlorobenzene when the extraction process began. The main advantages of this method are quick speed, high enrichment factor, high recovery and good repeatability. Under the optimum conditions, the method yields a linear calibration curve in the concentration range from 2 to 2000 microg kg(-1)for PCB 52, and 0.4 to 400 microg kg(-1) for other target analytes. Coefficients of correlation (r(2)) ranged from 0.9993 to 0.9999. The repeatability was tested by spiking soil samples at a concentration level of 10 microg kg(-1) for PCBs. The relative standard deviations (RSDs, n=11) varied between 2.2% and 6.4%. The limits of detection (LODs), based on signal-to-noise (S/N) of 3, were between 0.20 and 0.50 microg kg(-1). The relative recoveries of the five PCBs from soil S1, S2 and S3 at spiking levels of 10, 20 and 50 microg kg(-1) were in the range of 88.70-103.8%, 82.50-106.3% and 82.30-113.6%, respectively. Therefore, DLLME combined with GC-ECD can be successfully applied for the determination of trace PCB residues in real soil samples.

Application of dispersive liquid-liquid microextraction for the analysis of triazophos and carbaryl pesticides in water and fruit juice samples.

In this work, a simple, rapid and sensitive sample pretreatment technique, dispersive liquid-liquid microextraction (DLLME) coupled with high performance liquid chromatography-fluorescence detection (HPLC-FLD), has been developed to determine carbamate (carbaryl) and organophosphorus (triazophos) pesticide residues in water and fruit juice samples. Parameters, affecting the DLLME performance such as the kind and volume of extraction and dispersive solvents, extraction time and salt concentration, were studied and optimized. Under the optimum extraction conditions (extraction solvent: tetrachloroethane, 15.0 microL; dispersive solvent: acetonitrile, 1.0 mL; no addition of salt and extraction time below 5s), the performance of the proposed method was evaluated. The enrichment factors for the carbaryl and triazophos were 87.3 and 275.6, respectively. The linearity was obtained in the concentration range of 0.1-1000 ng mL(-1) with correlation coefficients from 0.9991 to 0.9999. The limits of detection (LODs), based on signal-to-noise ratio (S/N) of 3, ranged from 12.3 to 16.0 pg mL(-1). The relative standard deviations (RSDs, for 10 ng mL(-1) of carbaryl and 20 ng mL(-1) of triazophos) varied from 1.38% to 2.74% (n=6). The environmental water (at the fortified level of 1.0 ng mL(-1)) and fruit juice samples (at the fortified level of 1.0 and 5.0 ng mL(-1)) were successfully analyzed by the proposed method, and the relative recoveries of them were in the range of 80.4-114.2%, 89.8-117.9% and 86.3-105.3%, respectively.

Determination of four aromatic amines in water samples using dispersive liquid-liquid microextraction combined with HPLC.

A new method for the determination of four aromatic amines in water samples was developed by using dispersive liquid-liquid microextraction (DLLME) technique combined with HPLC-variable wavelength detection (HPLC-VWD). In this extraction method, 0.50 mL methanol (as dispersive solvent) containing 25.0 microL tetrachloroethane (as extraction solvent) was rapidly injected by a syringe into 5.00 mL water sample. Accordingly, a cloudy solution was formed. After centrifugation for 2 min at 4000 rpm, the fine droplets of the tetrachloroethane containing the analytes were sedimented in the bottom of the conical test tube (7+/-0.2 microL). Then, 5.0 microL of the settled phase was determined by HPLC-VWD. Parameters such as the kind and volume of extraction solvent and dispersive solvent, extraction time, and salt concentration were optimized. Under the optimum conditions, the enrichment factors ranged from 41.3 to 94.5. Linearity was observed in the range of 5-5000 ng/mL. The LODs based on S/N of 3 ranged from 0.8 to 1.8 ng/mL. The RSDs (for 400 ng/mL of p-toluidine and o-chloroaniline, 100 ng/mL of p-chloroaniline and p-bromoaniline) varied from 4.1 to 5.3% (n=6). The water samples collected from rivers and lakes were successfully analyzed by the proposed method and the relative recoveries were in the range of 85.4-111.7% and 90.2-101.3%, respectively.

Dispersive liquid-liquid microextraction followed by reversed phase HPLC for the determination of decabrominated diphenyl ether in natural water.

A simple, rapid, and efficient method, dispersive liquid-liquid microextraction (DLLME), has been developed for the extraction and preconcentration of decabrominated diphenyl ether (BDE-209) in environmental water samples. The factors relevant to the microextraction efficiency, such as the kind and volume of extraction and dispersive solvent, the extraction time, and the salt effect, were optimized. Under the optimum conditions (extraction solvent: tetrachloroethane, volume, 22.0 microL; dispersive solvent: THF, volume, 1.00 mL; extraction time: below 5 s and without salt addition), the most time-consuming step is the centrifugation of the sample solution in the extraction procedure, which is about 2 min. In this method, the enrichment factor could be as high as 153 in 5.00 mL water sample, and the linear range, correlation coefficient (r(2)), detection limit (S/N = 3), and precision (RSD, n = 6) were 0.001-0.5 microg/mL, 0.9999, 0.2 ng/mL, and 2.1%, respectively. This method was successfully applied to the extraction of BDE-209 from tap, East Lake, and Yangtse River water samples; the relative recoveries were 95.8, 92.9, and 89.9% and the RSD% (n = 3) were 1.9, 2.7, and 3.5%, respectively. Comparison of this method with other methods, such as solid-phase microextraction (SPME), and single-drop microextraction (SDME), indicates that DLLME is a simple, fast, and low-cost method for the determination of BDE-209, and thus has tremendous potential in polybrominated diphenyl ethers (PBDEs) residual analysis in environmental water samples.

Homogeneous liquid-liquid extraction combined with gas chromatography-electron capture detector for the determination of three pesticide residues in soils.

In this study, a new method was developed for analyzing malathion, cypermethrin and lambda-cyhalothrin from soil samples by using homogeneous liquid-liquid extraction (HLLE) and gas chromatography with electron capture detector (GC-ECD). Acetone was used as extraction solvent for the extraction of target pesticides from soil samples. When the extraction process was finished, the target analytes in the extraction solvent were rapidly transferred from the acetone extract to carbon tetrachloride, using HLLE. Under the optimum conditions, linearity was obtained in the range of 0.05-40 microg kg(-1) for malathion, 0.04-10 microg kg(-1) for lambda-cyhalothrin and 0.05-50 microg kg(-1) for cypermethrin, respectively. Coefficients of correlation (r(2)) ranged from 0.9993 to 0.9998. The repeatability was carried out by spiking soil samples at concentration levels of 2.5 microg kg(-1) for lambda-cyhalothrin, and 10 microg kg(-1) for malathion and cypermethrin, respectively. The relative standard deviations (RSDs) varied between 2.3 and 9.6% (n=3). The limits of detection (LODs), based on signal-to-noise ratio (S/N) of 3, varied between 0.01 and 0.04 microg kg(-1). The relative recoveries of three pesticides from soil A1, A2 and A3 at spiking levels of 2.5, 5 and 10 microg kg(-1) were in the range of 82.20-91.60%, 88.90-110.5% and 77.10-98.50%, respectively. In conclusion, the proposed method can be successfully applied for the determination of target pesticide residues in real soil samples.