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The calyx of Physalis alkekengi is rich in various bioactive components. In this study, ultrasonic assisted ethanol solvent was used to extract the total flavonoids using calyx of Physalis alkekengi as materials, and the effects of ultrasonic power, extraction temperature, ultrasonic time, ethanol volume fraction and solid -liquid ratio on the yields of total flavonoids were investigated, then the L16(45) orthogonal test was used to further optimize the extraction parameters on the basis of single factor experiments, in order to efficiently and fully extract the total flavonoids. The results showed that the optimal extraction process was determined as follows: ultrasonic power of 180 W, extraction temperature of 60 °C, 60% ethanol solution soaked for 24 h with solid-liquid ratio of 1:20(g/mL), and ultrasonic time of 50 min. Under these conditions, the yield of total flavonoids was 2.982%. The process in this paper is simple with low preparation cost, which is convenient for industrial production and helpful to the comprehensive utilization and development for calyx of Physalis alkekengi. [ABSTRACT FROM AUTHOR]

The exploitation of iron ore could cause heavy metals pollution in the soils, which threatens the ecosystem and human health. In this study, soil, stream sediment, tailings, rock, and atmospheric deposition samples were collected from an iron mine in Baotou City. The concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, Zn, Al2O3, CaO, K2O, MgO, Na2O, SiO2, and Fe2O3, as well as the mineral composition and heavy metal speciation of the samples, were analyzed for pollution assessment and source identification of heavy metals. The results reveal that the concentration of Cu in the soils was significantly higher than the background value, and an unpolluted to moderately polluted state was the main pollution level. By analyzing the relationship between Cu/Al2O3 and CaO in different samples, as well as the characteristics of the chemical index of alteration (CIA), mineral composition, and the chemical speciation of Cu in soils and profiles, the results suggest that tailings were the source of Cu pollution in soils. The distribution characteristics of Cu and CaO in stream sediments indicated that hydraulic transport may be one of the main migration pathways. In addition, wind transport may also be a pathway of migration. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus exists widely in the natural environment and is one of the main food-borne pathogenic microorganisms causing human bacteremia. For safe food management, a rapid, high-specificity, sensitive method for the detection of S. aureus should be developed. In this study, a platform for detecting S. aureus (nuc gene) based on isothermal amplification (loop-mediated isothermal amplification—LAMP, recombinase polymerase amplification—RPA) and the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas12a) proteins system (LAMP, RPA-CRISPR/Cas12a) was proposed. In this study, the LAMP, RPA-CRISPR/Cas12a detection platform and immunochromatographic test strip (ICS) were combined to achieve a low-cost, simple and visualized detection of S. aureus. The limit of visual detection was 57.8 fg/µL of nuc DNA and 6.7 × 102 CFU/mL of bacteria. Moreover, the platform could be combined with fluorescence detection, namely LAMP, RPA-CRISPR/Cas12a-flu, to establish a rapid and highly sensitive method for the detection of S. aureus. The limit of fluorescence detection was 5.78 fg/µL of genomic DNA and 67 CFU/mL of S. aureus. In addition, this detection platform can detect S. aureus in dairy products, and the detection time was ~40 min. Consequently, the isothermal amplification CRISPR/Cas12a platform is a useful tool for the rapid and sensitive detection of S. aureus in food. [ABSTRACT FROM AUTHOR]

Aim This study aimed to investigate the high-resolution phenotypic and genotypic characterization of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli strains isolated from hospitalized patients to explore the resistance genes and mobile genetic elements (MGEs) involved in horizontal dissemination. Methods Between May and September 2021, a total of 216 ESBL-producing E. coli isolates were recovered from multiple departments. The identification of strains was performed using MALDI-TOF mass spectrometry and PCR, while antibiotic susceptibility testing was carried out using the Vitek 2 COMPACT system to determine resistance patterns, while PCR was used to detect different resistance genes and MGEs. In addition, a conjugation assay was performed to investigate the horizontal gene transfer of resistance genes. Selected isolates underwent whole-genome sequencing (WGS) using the Illumina MiSeq platform. Results A total of 216 out of 409 E. coli isolates recovered from a tertiary hospital were observed to be ESBL-producing, giving a carriage rate of 52.8%, as determined by phenotypic screening. The most frequent sources of ESBL-producing E. coli isolates were urine (129/216, 59.72%) and blood (50/216, 23.14%). The most prevalent ESBL genes identified were bla CTX-M (60.18%), bla TEM (40.27%), and bla SHV (18.05%). Three E. coli isolates were found to carry the genes bla NDM, mcr-1 , and fosA3 genes. The most prevalent MGEs were IS 26 (95.37%), Int (87.03%), and IncFIB (76.85%). WGS analysis of eight MDR E. coli strains revealed that these isolates belonged to eight different sequence types (STs) and serotypes and were found to harbor multiple plasmid replicons and virulence factors. Conclusion This study highlights a high incidence of antibiotic resistance genes and MGEs associated with the dissemination of ESBLs and other resistance genes. [ABSTRACT FROM AUTHOR]

Background: This research focused on evaluating the correlation between platelet count and sepsis prognosis, and even the dose-response relationship, in a cohort of American adults., Method: Platelet counts were recorded retrospectively after hospitalization for patients admitted to Beth Israel Deaconess Medical Center's intensive care unit between 2008 and 2019. On admission to the intensive care unit, sepsis patients were divided into four categories based on platelet counts (very low < 50 × 10 9 /L, intermediate-low 50 × 10 9 -100 × 10 9 /L, low 100 × 10 9 -150 × 10 9 /L, and normal ≥ 150 × 10 9 /L). A multivariate Cox proportional risk model was used to calculate the 28-day risk of mortality in sepsis based on baseline platelet counts, and a two-piece linear regression model was used to calculate the threshold effect., Results: The risk of 28-day septic mortality was nearly 2-fold higher in the platelet very low group when compared to the low group (hazard ratios [HRs], 2.24; 95% confidence interval [CI], 1.92-2.6). Further analysis revealed a curvilinear association between platelets and the sepsis risk of death, with a saturation effect predicted at 100 × 10 9 /L. When platelet counts were below 100 × 10 9 /L, the risk of sepsis 28-day death decreased significantly with increasing platelet count levels (HR, 0.875; 95% CI, 0.84-0.90)., Conclusion: When platelet count was less than 100 × 10 9 /L, it was a strong predictor of the potential risk of sepsis death, which is declined by 13% for every 10 × 10 9 /L growth in platelets. When platelet counts reach up to 100 × 10 9 /L, the probability of dying to sepsis within 28 days climbs by 1% for every 10 × 10 9 /L increase in platelet count., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Wang, Wu, Gao, Huang, Xu and Ru.)