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ObjectiveTo establish a method using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for the detection of six common trichothecene toxins in oats.MethodsOats were selected as the research subject in this study. Response surface design was used to optimize the QuEChERS extraction method. Additionally, a rapid and efficient strategy for sample extraction and purification was developed. Combined with UHPLC-MS/MS, six commonly co-occurring trichothecene toxins in oats were quantitatively analyzed simultaneously.ResultsThis method demonstrated good analytical performance for each analyte across the corresponding concentration ranges (r>0.99), with accuracy ranging from 87.26% to 99.64%. The inter-day and intra-day relative standard deviations were less than 6.8% and 5.5%, respectively, indicating its potential for practical application. This method was used to detect mycotoxins in 12 oat samples from China, and it was found that one sample exceeded the standard limits for deoxynivalenol (DON), and the co-contamination of trichothecene toxin was prevalent.ConclusionThe risk posed by these toxins has been underestimated. Ongoing, extensive monitoring is necessary to provide contamination data to assess the consumer risk.

ObjectiveTo explore the effect of sous-vide on the thermal inactivation rules of Listeria monocytogenes in different matrix， the thermal inactivation of Listeria monocytogenes in different substrates at different temperatures was studied.MethodsFive lyophiliZed L. monocytogenes strains were inoculated into saline， MH broth， vacuum packed lean pork and streaky pork. The survival rates were evaluated at 55， 60， and 63 ℃. The decimal reduction time （D-value） and temperature dependence （Z-value） were determined for each strain in each matrix.ResultsThe D value and Z value of Listeria monocytogenes in pork were higher than those in normal saline and MH broth， the difference was statistically significant （P

BackgroundThe EnSite Precision™ cardiac mapping system (Abbott) is a catheter navigation and mapping system capable of displaying the three-dimensional (3D) position of conventional and sensor-enabled electrophysiology catheters, as well as displaying cardiac electrical activity as waveform traces and dynamic 3D maps of cardiac chambers. The EnSite Precision™ Observational Study (NCT-03260244) was designed to quantify and characterize the use of the EnSite Precision™ cardiac mapping system for mapping and ablation of cardiac arrhythmias in a real-world environment and evaluate procedural outcomes.MethodsA total of 1065 patients were enrolled at 38 centers in the USA and Canada between 2017 and 2018 and were followed for 12 months post procedure for arrhythmia recurrence, medication use, and quality-of-life changes. Eligible subjects were adults undergoing a cardiac electrophysiology mapping and radiofrequency ablation procedure using the EnSite Precision™ System.ResultsA final cohort of 925 patients (64.3 years of age, 30.2% female) were analyzed. The primary procedural indication was atrial flutter in 48.1% (445/925), atrial fibrillation in 46.5% (430/925), and other arrhythmias in 5% (50/925). Electroanatomic mapping was performed in 81.5% (754/925) of patients. Mapping was stable throughout 79.8% (738/925) of procedures with initial mapping time of 8.6 min (IQR 4.7-15.0). Average mapping efficiency created with AutoMap or TurboMap was 164.9 ± 365.7 used points per minute. Median number of mapping points collected and used was 1752.5 and 811.0, respectively. Only 335/925 (36.2%) required editing and 66.0% (221/335) of these patients required editing of less than 10 points. Fluoroscopy was utilized in most cases (n = 811/925, 87.4%) with fluoroscopy time of 11.0 min (IQR 6.0-18.0). Overall median procedure time was 101.0 min (IQR 59.0-152.0). Acute procedural success was high for both atrial fibrillation (n = 422/430, 98.1%) and atrial flutter (n = 434/445, 97.5%).ConclusionIn a real-world study analysis, use of the EnSite Precision™ mapping system was associated with high procedural stability, short mapping times, high point density requiring infrequent editing, low fluoroscopy time, and high prevalence of acute procedural success.

ObjectiveTo investigate the impact of edible vegetable varieties， temperatures， and inoculation sites on the survival of Listeria monocytogenes （L. monocytogenes）， providing a theoretical foundation for risk assessment and key control measures of L. monocytogenes in edible vegetables.MethodsFreeze-dried quantitative L. monocytogenes served as the strain source， with the surfaces and sections of five edible vegetables （colored pepper， onion， cucumber， virgin fruit and lettuce） used as inoculation sites. The strain was cultured at both 4 ℃ and 25 ℃ for 7 days. Regular monitoring of the L. monocytogenes quantity in each sample was conducted， and growth was analyzed.ResultsThe quantity of L. monocytogenes freeze-dried in different bottles was uniform （F=1.923， P

ObjectiveThis study aimed to develop ready-to-use standard strains of Salmonella typhimurium （S. typhimurium） TA97， TA98， TA100， and TA102 for mutagenicity testing.MethodsFreeze-dried strains of S. typhimurium TA97， TA98， TA100， and TA102 at both high and low concentrations were quantified. The spontaneous reversion rate of the freeze-dried strains after 3， 5， 7， and 18 h was measured. Homogeneity， storage and transportation stability， spontaneous revertant frequency， and mutagenic agent mutation rate of the ready-to-use standard strains were evaluated following the CNAS-GL003 2018 “Guidelines for the Evaluation of Homogeneity and Stability of Proficiency Testing Samples” and GB 15193.4—2014 “National Food Safety Standard - Bacterial Reverse Mutation Test.” Standard deviations of spontaneous revertant frequency and mutagenic agent mutation rate test results between 20 ready-to-use standard strains and fresh strains were compared.ResultsHigh-concentration lyophilized samples had concentrations ranging from 107-108 CFU/sample， while low-concentration samples had concentrations ranging from 105-106 CFU/sample. The spontaneous reversion rate results after 18 h of incubation met the requirements of GB 15193.4—2014. Homogeneity results for the four ready-to-use standard strains showed F-values of 1.12， 1.05， 1.68， and 1.38， with F < F0.05 （19，20）， meeting CNAS-GL003 requirements. The detection results for the four freeze-dried strains stored at 25 ℃ for 5 d， 4 ℃ for 14 d， and -20 ℃ for 6 months met storage and transportation stability requirements. The standard deviation of spontaneous revertant frequency in the 20 ready-to-use freeze-dried standard strains was smaller than that of fresh strains.ConclusionThe ready-to-use standard strains developed in this study exhibit excellent homogeneity， storage， and transportation stability. Moreover， the stability of spontaneous revertant frequency in the ready-to-use freeze-dried standard strains surpasses that of fresh strains.