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Abstract Background mcr-1-positive Escherichia coli has emerged as a significant threat to human health, veterinary health, and food safety in recent years. After the prohibition of colistin as a feed additive in animal husbandry in China, a noticeable reduction in both colistin resistance and the prevalence of mcr-1 was observed in E. coli from animals and humans. Objectives To assess the prevalence of the colistin resistance gene mcr-1 and characterize its genetic context in E. coli strains derived from fecal and meat samples from food-producing animals in China. Methods A total of 1,353 fecal samples and 836 food samples were collected between 2019 and 2020 in China. E. coli isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and their susceptibility to colistin were determined using the broth microdilution method. The colistin-resistant E. coli isolates were screened for the presence of mcr by PCR analysis and sequencing. The minimal inhibitory concentrations (MICs) of 15 antimicrobial agents against the mcr-1-positive strains were further tested using the agar dilution method, conjugation assays were performed, and whole genome sequencing was performed using Illumina HiSeq. Results In total, 1,403 E. coli strains were isolated. Thirteen isolates from chicken meat (n = 7), chickens (n = 3), and pigs (n = 3) were resistant to colistin with MIC values of 4 to 16 mg/L, and carried mcr-1. All mcr-1-positive strains, except for isolate AH20PE105, contained multiple resistance genes and exhibited multidrug-resistant phenotypes. They belonged to 10 sequence types (STs), including a novel ST (ST14521). mcr-1 was located on IncI2 (n = 9), IncX4 (n = 2), and IncHI2 (n = 2) plasmids, which were highly similar to other mcr-1-carrying plasmids sharing the same incompatibility type. Seven mcr-1-carrying plasmids could be successfully conjugally transferred to E. coli C600. Conclusions While the low prevalence of mcr-1 (0.93%) identified in this study may not immediately seem alarming, the very emergence of this gene merits attention given its implications for colistin resistance and public health. Hence, ongoing surveillance of mcr-1 in E. coli remains crucial.

Objective To explore the effect of short-term semi-immersion teaching and training based on the learning pyramid model to improve the capacity building of to find early gastric cancer by digestive endoscope physicians. Methods Thirty digestive refresher doctors were randomly selected from our center for 4-week semi-immersion training. The capacity of the trainees to recognize early gastric cancer was tested before and after 4 weeks of training, and the accuracy of the test was compared. Results The accuracy of the test before training, after theoretical lesson and after 4 weeks of training were 44.58%±16.39%, 48.54%±16.95% and 68.75%±12.06% respectively. The test accuracy after theory lesson plus 4 weeks of training was higher than that before training and after only theoretical lesson (P＜0.001).The test accuracy after theoretical lesson was higher than that before the training(P＜0.05). When grouping by the number of cases in previous gastroscopy, no matter before training or after theoretical lesson, the test accuracy with experience in testing was higher than group with less experience. However, the test accuracy of the two groups almost reached a same level after 4 weeks of training(P＜0.01). With the extension of training time, the test accuracy gradually increased (P＜0.001). There was an interaction between grouping and training time (P＜0.001).In the correlation analysis, the number of cases of the previous gastroscopy performance was positively correlated with the test accuracy before training and after theoretical lesson (r=0.668,＜0.001,r=0.581, P＜0.01). Conclusions Semi-immersion training guided by the learning pyramid model can effectively improve the capacity of digestive endoscope physicians to recognize early gastric cancer.

This study aimed to investigate the influence of varying concentrations of Flammulina velutipes powder (FVP) (0, 4, 8, 12, 16, and 20 g L−1, based on FVP weight per liter of emulsion) on the stability, rheological properties, microstructure, and interfacial protein content of chicken myofibrillar protein (MP) emulsions under low‐salt conditions. Visual assessment and the Turbiscan stability index revealed that the stability of MP emulsions improved with increasing FVP concentration. The greatest stability was achieved when the FVP concentration was 16 gL−1. The incorporation of FVP enhanced the elasticity and viscosity of the emulsions by forming a dense three‐dimensional network structure. The droplet size of the emulsions initially decreased and then increased with increasing FVP concentration. The addition of FVP increased the amount of protein absorbed by the emulsion layer. Flammulina velutipes powder is promising as a stabilizer that could improve the emulsifying and functional properties of low‐salt myofibrillar protein emulsions. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aimed to investigate the prevalence and genomic characteristics of the colistin resistance gene mcr in Salmonella enterica in China. In total, 445 S. enterica isolates from animals and food products were screened through PCR and sequencing for the presence of mcr. The mcr genes were detected in nine Salmonella strains (2.02%), with complete mcr-1 in S. enterica serovar Indiana (n = 1) and an S. Typhimurium monophasic variant (S. 4,[5],12:i:-; n = 1), mcr-4.3 in S. enterica serovar London (n = 1), and an incomplete mcr-1 in S. Indiana (n = 6). They exhibited MIC values of 0.25 to 8 mg/L to colistin and showed resistance to multiple antimicrobial agents. Whole-genome sequencing was performed on mcr-positive Salmonella strains using Illumina HiSeq or PacBio single-molecule real-time sequencing. The complete mcr-1 gene was located on conjugative IncN1-IncHI2 plasmid and IncX4 plasmid, respectively, with high similarity to other mcr-1-bearing plasmids belonging to the same incompatibility type. Together with an additional 13 antimicrobial resistance genes, the incomplete mcr-1 was embedded in an 81,442-bp multiresistance region on the chromosome in S. Indiana YZ20MCS6. The Δmcr-1-pap2 segment and a set of tellurite resistance determinants (terYXWZABCDEF) in six S. Indiana strains were similar to other IncHI2 plasmid backbones. The mcr-4.3 gene was located on an untyped plasmid pYULZMPS10. Although low prevalence of mcr was observed in Salmonella, continuous surveillance of this gene in Salmonella is required. Plasmids play an important role in mcr transmission, and mcr-1, although incomplete, can be captured by chromosomes with the help of mobile elements. IMPORTANCE Colistin is a last-resort antibiotic for severe infections caused by multidrug-resistant (MDR) Gram-negative pathogens. Colistin resistance genes mcr, particularly mcr-1, have been found in Enterobacteriaceae around the world, mainly in Escherichia coli and Salmonella. Salmonella enterica is a major foodborne pathogen, with MDR Salmonella being considered a “Serious Threat Level pathogen” by the Centers for Disease Control and Prevention. Therefore, the prevalence of mcr in Salmonella strains must be monitored. In this study, a low mcr prevalence (2.02%) was observed in Salmonella strains from animals and food products, with plasmid-borne mcr-1 in S. enterica serovar Indiana and an S. Typhimurium monophasic variant (S. 4,[5],12:i:-) and chromosomally located mcr-1 in S. Indiana. The mcr-4.3 gene was first identified in S. enterica serovar London associated with an untyped plasmid. Although this study reports a low mcr prevalence in Salmonella, the transmission ability of mcr-positive Salmonella strains to humans via the food chain is a public health concern.

Background and Objectives: The anatomical characteristics of patients with mitral valve prolapse (MVP) and mitral regurgitation (MR) have rarely been investigated demographically to determine the applicability of transcatheter intervention. Therefore, the study objective was to analyze potential candidates and their prognosis. Predictors determining the prognosis were also investigated. Methods: Patients diagnosed with MVP and MR severity of ≥2+ were screened from our echocardiography database from 2010 to 2012. All clinical and echocardiogram information was retrieved from electronic medical records. The endpoint was all-cause mortality analyzed by a proportional hazards model. Results: A total of 1268 patients (mean age 57.50 ± 14.88 years, 47.16% female) with MVP and MR severity of ≥ 2+ were included. Isolated P2 (n = 239, 18.85%) appeared as the most common site of leaflet prolapse. The incidence of MR jet solely from middle scallop (A2 and/or P2) was 31.07% (n = 394). If a nonsignificant jet from other locations was also accepted, the incidence of MR jet derived from mainly the middle scallop (A2 and/or P2) was 52.10% (n = 659). For MVP patients with MR R + 3, the conservative therapy group had higher mortality than the early surgery group (31.45% vs. 5.25%, P < 0.001) after 4.5 ± 1.0 years of follow-up, multiple analysis showed that surgical treatment (hazard ratio [HR]: 0.202, P < 0.001), systolic pulmonary artery pressure of o60 mmHg (HR: 6.816, P < 0.001), age of ≥ 60 years (HR: 3.838, P < 0.001), and pericardial effusion (HR: 1.915, P = 0.003) were independent predictors of all-cause mortality. Conclusions: In patients with MVP, one-fifth leaflet prolapse located solely in P2 and one-half of MR jet derived from the middle scallop were anatomically eligible for transcatheter chordal repair and edge-to-edge repair therapy, respectively. Initial conservative therapy, pericardial effusion, pulmonary hypertension, and advanced age were independent predictors of a higher mortality rate in MVP patients with MR severity of ≥ 3+.

We report the fourth installment in the series of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) quasar survey, which includes quasars observed between 2017 September and 2021 June. There are in total 13,066 quasars reliably identified, of which 6685 are newly discovered that are not reported in the Sloan Digital Sky Survey (SDSS) DR14 quasar catalog or Million Quasars catalog. Because LAMOST does not provide accurate absolute flux calibration, we recalibrate the spectra with the SDSS/Pan-STARRS1 multiband photometric data. The emission-line properties of H α , H β , Mg ii , and C iv and the continuum luminosities are measured by fitting the recalibrated spectra. We also estimate the single-epoch virial black hole masses ( M _BH ) using the derived emission-line and continuum parameters. This is the first time that the emission-line and continuum fluxes were estimated based on LAMOST recalibrated quasar spectra. The catalog and spectra for these quasars are available online. After the 9 yr LAMOST quasar survey, there are in total 56,175 identified quasars, of which 24,127 are newly discovered. The LAMOST quasar survey not only discovers a great number of new quasars but also provides a database for investigating the spectral variability of the quasars observed by both LAMOST and SDSS and finding rare quasars, including changing-look quasars and broad absorption line quasars.

BackgroundRecurrent laryngeal nerve (RLN) lymph node metastasis (LNM) is not rare in patients with esophageal squamous cell carcinoma (ESCC). We aimed to develop and externally validate a preoperative nomogram using clinical characteristics to predict RLN LNM in patients with ESCC and evaluate its prognostic value.MethodsA total of 430 patients with ESCC who underwent esophagectomy with lymphadenectomy of RLN LNs at two centers between May 2015 and June 2019 were reviewed and divided into training (center 1, n = 283) and external validation cohorts (center 2, n = 147). Independent risk factors for RLN LNM were determined by multivariate logistic regression, and a nomogram was developed. The performance of the nomogram was assessed in terms of discrimination, calibration, clinical usefulness, and prognostic value. The nomogram was internally validated by the bootstrap method and externally validated by the external validation cohort.ResultsMultivariate analysis indicated that clinical T stage (P