A convenient and fast multiresidue method for the efficient identification and quantification of 72 pesticides belonging to different chemical classes in red and white grape wines have been developed. The analysis was based on gas chromatography tandem quadrupole mass spectrometric determination (GC–MS/MS). An optimization strategy involved the selection of MWCNTs amount and cleanup procedure cycle times for m-PFC was performed to achieve ideal recoveries and reduce sample matrix compounds in the final extracts. The optimized procedure obtained consistent recoveries between 70.2 and 108.8% (70.2% and 108.8% for white wine, 72.3% and 106.0% for red wine) , with relative standard deviations (RSDs) generally lower than 8.3% at three spiking levels of 0.01, 0.05 and 0.2 mg/kg. Linearity was studied in the range between 0.005 and 0.2 mg/kg using pesticide standards prepared both in pure solvent and in the presence of matrix, showing coefficients of determination (R²) higher than 0.985 for all the pesticides. To improve accuracy, matrix matched calibration curves were used for calculating the quantification results. Finally, the method was used successfully in detecting pesticide residues in commercial gape wines.

Background A limited lymphadenectomy may make patients with esophageal squamous cell carcinoma (ESCC) at risk for missing occult nodal disease. This study aimed to determine an effective threshold of lymph nodes (LNs) for evaluation of the quality of lymphadenectomy and discuss the impact of adjuvant chemotherapy on pN0 patients. Methods Patients treated surgically for ESCC between 2010 and 2018 in Sichuan Cancer Hospital were included. NPV (Negative Predictive Value) based on a beta-binomial distribution was developed to assess the confidence of node-negative disease. Kaplan-Meier curves were plotted to compare survival differences among groups. Results When patients had >21 LNs examined, the probability of false-negative findings was estimated at <10%, and NPV was estimated at a high level (>86.5%). For patients with LNs removed ≤21, 5-year OS (or DFS) in postoperative chemotherapy group vs that in surgery group was 65.3% vs 54.6%, p = 0.041 (or 59.2% vs 46.6%, p = 0.033). But for patients with >21 LNs, there were no statistical differences (p = 0.683 for OS or p = 0.942 for DFS). Conclusion Only pN0 patients who were at high risk of occult lymph node metastasis (examined LNs ≤21) could benefit from postoperative chemotherapy.