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It is of vital importance to evaluate the environmental risks brought by sulfuryl fluoride before applying it wildly as an alternative to aluminum phosphide in grain storage.Degradation kinetics of 350 mg/m3 ozone was investigated under sulfuryl fluoride concentrations of 5,10 and 20 g/m3.The results show that ozone degradation was significantly accelerated by sulfuryl fluoride in air.The half-life of ozone concentration in the sulfuryl fluoride-free environment is 275.2 min,while the half-lives of ozone in the 5,10,and 20 g/m3 sulfuryl fluoride concentration are 157.4,166.4 and 161.8 min,respectively.In this study,we compared the sulfuryl fluoride elimination of active carbon,neutral aluminum oxide,calcium hydroxide suspension and sodium hydroxide solutions to eliminate sulfuryl fluoride,and sodium hydroxide solution was employed finally.The study found that temperature is a key factor in the process of sulfuryl fluoride elimination.The half-lives of sulfuryl fluoride were 592.5,404.2,and 323.5 min at 20,25,and 30 ℃,while the sodium hydroxide solution was 0.25 mol/L.

Abstract Background Patients with prior illness are more vulnerable to heat stroke-induced injury, but the underlying mechanism is unknown. Recent studies suggested that NLRP3 inflammasome played an important role in the pathophysiology of heat stroke. Methods In this study, we used a classic animal heat stroke model. Prior infection was mimicked by using lipopolysaccharide (LPS) or lipoteichoic acid (LTA) injection before heat stroke (LPS/LTA 1 mg/kg). Mice survival analysis curve and core temperature (TC) elevation curve were produced. NLRP3 inflammasome activation was measured by using real-time PCR and Western blot. Mice hypothalamus was dissected and neuroinflammation level was measured. To further demonstrate the role of NLRP3 inflammasome, Nlrp3 knockout mice were used. In addition, IL-1β neutralizing antibody was injected to test potential therapeutic effect on heat stroke. Results Prior infection simulated by LPS/LTA injection resulted in latent inflammation status presented by high levels of cytokines in peripheral serum. However, LPS/LTA failed to cause any change in animal survival rate or body temperature. In the absence of LPS/LTA, heat treatment induced heat stroke and animal death without significant systemic or neuroinflammation. Despite a decreased level of IL-1β in hypothalamus, Nlrp3 knockout mice demonstrated no survival advantage under mere heat exposure. In animals with prior infection, their heat tolerance was severely impaired and NLRP3 inflammasome induced neuroinflammation was detected. The use of Nlrp3 knockout mice enhanced heat tolerance and alleviated heat stroke-induced death by reducing mice hypothalamus IL-1β production with prior infection condition. Furthermore, IL-1β neutralizing antibody injection significantly extended endotoxemic mice survival under heat stroke. Conclusions Based on the above results, NLRP3/IL-1β induced neuroinflammation might be an important mechanistic factor in heat stroke pathology, especially with prior infection. IL-1β may serve as a biomarker for heat stroke severity and potential therapeutic method.

ABSTRACT The rapid emergence of multidrug-resistant/extensively drug-resistant tuberculosis (TB) is responsible for treatment failure in patients with TB and significantly endangers global public health. Recently, bioenergetics has become a new paradigm for anti-TB drug discovery and is based on the link between bacterial ATP levels and drug efficacy. A better understanding of the role of ATP fluctuations during antibiotic treatment may provide insight into antibiotic-mediated killing of mycobacteria. Here, we employed an advanced single-fluorescence FRET (fluorescence resonance energy transfer)-based ATP biosensor, ATPser, for the stable and convenient detection of intracellular ATP fluctuations in mycobacteria. This strategy correlated closely with the results obtained from conventional luminescence ATP assays, indicating the reliability of the system for bioenergetics analysis in mycobacteria. Moreover, the reporter strains expressing ATPser displayed obvious ATP changes when subjected to different stresses, such as starvation and ATP depletion. Interestingly, we observed that different antibiotics induced fluctuations in cellular ATP levels in individual cells of various magnitudes, revealing a strong connection between ATP fluctuations and drug efficacy. Furthermore, drug combinations accelerated ATP perturbation, resulting in increased cell death. We concluded that ATPser enabled real-time measurement of ATP at the single-cell level in mycobacteria, and monitoring ATP dynamics in drug-treated bacteria may shed light on novel treatment strategies. IMPORTANCE Bioenergetics has emerged as a new paradigm for antituberculosis (anti-TB) drug discovery, and the cellular ATP level is the core indicator reflecting bacterial metabolic homeostasis. Although several bulk assays have been designed for the measurement of cellular ATP content, a more convenient strategy is required for real-time ATP measurement of single viable cells. In this study, by combining the ε-subunit of Bacillus subtilis FoF1-ATP synthase with a circularly permuted green fluorescent protein [(cp)GFP], we constructed a FRET-based single-fluorescence ATP sensor, ATPser, for real-time single-cell ATP detection among a mycobacterial population. Using the ATPser, we designed different drug combinations containing components that have similar/opposite effects on ATP alternation. Our results demonstrated that increased cellular ATP fluctuations were associated with depletion of mycobacterial viability, while counteracting ATP fluctuations weakened the killing effect of the drug regime. Thus, potentially efficient drug combinations can be considered based on their similar effects on mycobacterial ATP levels, and ATPser may be a useful tool to study mycobacterial bioenergetics and to guide drug regime design.

BackgroundThere are few studies on predictive biomarkers for hyperuricemia, and the predictive value of these biomarkers tends to be poor. Additionally, no reports have described the predictive value of retinol binding protein 4 (RBP4) for hyperuricemia.PurposeThis study was performed to evaluate the value of RBP4 for predicting the risk of hyperuricemia in a general population, determine whether RBP4 could be used alone or in combination with other factors to predict the risk of hyperuricemia in the general population, and establish an optimum predictive model.MethodsWe conducted a population-based cross-sectional survey in 2018, involving a questionnaire, physical examination, and laboratory testing. We enrolled 2303 individuals by stratified random sampling, and 2075 were included in the data analysis after applying the eligibility criteria.ResultsSerum RBP4 level had a highly significant association with hyperuricemia (P

ABSTRACT Staphylococcus haemolyticus is an opportunistic pathogen associated with hospital-acquired infections. However, the genetic diversity of S. haemolyticus among the patients and the hospital environment is largely unknown. Here, we isolated 311 S. haemolyticus strains from different sampling sites of patients and hospital environment. Genomic analysis showed that ST42 is an emerging clone widely disseminated in the hospital. S. haemolyticus ST42 strains exhibited decreased susceptibilities for multiple antibiotics compared with other STs and carried significantly more antibiotic resistance genes (ARGs). Furthermore, ST42 strains harbored more virulence genes per isolate than in other STs, and the capsular biosynthesis genes capDEFG were more prevalent in ST42 strains. Using the Galleria mellonella infection model, we demonstrated that ST42 strains are highly virulent compared with non-ST42 strains. Taken together, our data identified an emerging ST42 clone of S. haemolyticus with aggregated ARGs and virulence determinants in the hospital, representing a significant health threat in terms of both disease and treatment. IMPORTANCE S. haemolyticus is an emerging opportunistic pathogen with a high burden of antimicrobial resistance. We performed molecular epidemiological analysis of S. haemolyticus that was isolated from a hospital, and found that the phylogenetic lineages are diverse accompanied by a dominant epidemic clonal lineage ST42. We demonstrated that S. haemolyticus ST42 strains have been disseminated among patients and the hospital environment. The data provide mechanistic insight and indicate that S. haemolyticus ST42 strains are multidrug-resistance and virulent clones via accumulating more ARGs and virulence genes.

Abstract Background World Health Organization recommends countries introducing new drug and short treatment regimen for drug resistant tuberculosis (DR-TB) should develop and implement a system for active pharmacovigilance that allows for detection, reporting and management of adverse events. The aim of the study is to evaluate the frequency and severity of adverse events (AEs) of bedaquiline-containing regimen in a cohort of Chinese patients with multidrug-resistant (MDR)/extensively drug-resistant (XDR)-TB based on active drug safety monitoring (aDSM) system of New Drug Introduction and Protection Program (NDIP). Methods AEs were prospectively collected with demographic, bacteriological, radiological and clinical data from 54 sites throughout China at patient enrollment and during treatment between February, 2018 and December, 2019. This is an interim analysis including patients who are still on treatment and those that have completed treatment. A descriptive analysis was performed on the patients evaluated in the cohort. Results By December 31, 2019, a total of 1162 patients received bedaquiline-containing anti-TB treatment. Overall, 1563 AEs were reported, 66.9% were classified as minor (Grade 1–2) and 33.1% as serious (Grade 3–5). The median duration of bedaquiline treatment was 167.0 [interquartile range (IQR): 75–169] days. 86 (7.4%) patients received 36-week prolonged treatment with bedaquiline. The incidence of AEs and serious AEs was 47.1% and 7.8%, respectively. The most frequently reported AEs were QT prolongation (24.7%) and hepatotoxicity (16.4%). There were 14 (1.2%) AEs leading to death. Out of patients with available corrected QT interval by Fridericia's formula (QTcF) data, 3.1% (32/1044) experienced a post-baseline QTcF ≥ 500 ms, and 15.7% (132/839) had at least one change of QTcF ≥ 60 ms from baseline. 49 (4.2%) patients had QT prolonged AEs leading to bedaquiline withdrawal. One hundred and ninety patients reported 361 AEs with hepatotoxicity ranking the second with high occurrence. Thirty-four patients reported 43 AEs of hepatic injury referred to bedaquiline, much lower than that referred to protionamide, pyrazinamide and para-aminosalicylic acid individually. Conclusions Bedaquiline was generally well-tolerated with few safety concerns in this clinical patient population without any new safety signal identified. The mortality rate was generally low. These data inform significant positive effect to support the WHO recent recommendations for the wide use of bedaquiline.

In response to the spread of colistin resistance gene mcr-1, China banned the use of colistin in livestock fodders. We used a time-series analysis of inpatient colonization data from 2011–2019 to accurately reveal the associated fluctuations of mcr-1 that occurred in inpatients in response to the ban.

Knowledge of the spatial and temporal variations in soil nutrients is crucial for designing efficient site-specific nutrient management plans, which can improve crop yields and maximize nutrient use efficiency. The present study was conducted to evaluate and compare the status and spatio-temporal distribution pattern of available nitrogen (AHN), phosphorus (AP) and potassium (AK) and some selected soil properties [soil pH and soil organic matter (SOM)] in cultivated soils of Southwestern China over a 15-year period (2007–2022). We visualized the correlations among soil properties, AHN, AP and AK and analyzed the spatial structures of these parameters. A total of 3845 topsoil (0–20 cm) samples (3331 in 2007 and 514 in 2022) were collected from the cultivated areas of Jiangjin District, Chongqing, Southwestern China. Soil pH, SOM, AHN and AK showed moderate variability with coefficient of variation (CV) values varying between 10 and 100%, except AP (CV > 100%, high variability). The mean soil pH, SOM, AP and AK in 2022 were significantly higher than those in 2007. AHN was significantly positively correlated with SOM (r = 0.531, p < 0.01 in 2007, r = 0.768, p < 0.01 in 2022) and significantly negatively correlated with soil pH (r = −0.186, p < 0.01 in 2007, r = −0.102, p < 0.05 in 2022). AP was significantly negatively correlated with soil pH (r = −0.075, p < 0.01 in 2007, r = −0.126, p < 0.01 in 2022). AK was significantly positively correlated with SOM (r = 0.164, p < 0.01 in 2007, r = 0.229, p < 0.01 in 2022), ANH (r = 0.131, p < 0.01 in 2007, r = 0.251, p < 0.01 in 2022) and AP (r = 0.145, p < 0.01 in 2007, r = 0.52, p < 0.01 in 2022). The exponential function performed best for the soil properties and all three nutrients, with higher R2 values (0.203 to 0.93 in 2007 and 0.316 to 0.796 in 2022) in both years. The nugget/sill ratios (which varied from 31.58% to 72% in 2007 and from 29.31% to 47.02% in 2022) indicated the moderate spatial dependence of all soil parameters, except AK in 2022 (nugget/sill ratio = 23.81%, strong spatial dependence). During the study period, soil pH, AP and AK increased in the central and northern areas; SOM increased in the northern and southwestern parts; AHN decreased in the central areas. The current study highlighted the change in spatial variability of soil pH, AHN, AP and AK in the study area over 15 years. [ABSTRACT FROM AUTHOR]

This paper is concerned with the propagation dynamics of a three-species nonlocal dispersal predator–prey system with two weak competing aborigine preys. Precisely, our main concern is the invading process of an alien predator into the habitat of two aborigine preys, when two preys are weak competitors in the absence of predator. This invasion process can be characterized by the spreading speed of the predator as well as the traveling wave solutions connecting the predator-free state to other states. First, by applying Schauder’s fixed point theorem with the help of two pairs of upper and lower solutions, we prove that there exists a positive number c∗, when the wave speed is large than or equals to c∗, the system admits a traveling wave solution connecting the predator-free state to the co-existence state, which indicates the occurrence of invasion-coexistence phenomenon. Then the invading speed of the predator is investigated by using the comparison argument. Our results show that (i) the weak interspecific competition between two preys will not affect the phenomenon of invasive-coexistence; (ii) the invading speed of the predator coincides with the minimal wave speed c∗. [ABSTRACT FROM AUTHOR]

Ga2O3/MCM-41-x (x = 0.4, 0.5, 0.6) heterogeneous catalysts, each with varying levels of Br doping, were synthesized using mesoporous molecular sieves (MCM-41) as a carrier and employed in the synthesis of propylene carbonate (PC) from propylene oxide (PO) and carbon dioxide (CO2). The reaction was conducted under solvent-free and additive-free conditions. Various techniques were utilized to characterize the catalysts' chemical composition, morphology, and structure. The effects of varied reaction conditions on PO conversion and PC selectivity using Ga2O3/MCM-41-0.5 catalysts were investigated. Under the reaction conditions of 120 °C, 3.5 MPa, 10 h and catalyst dosage of 2.6 wt%, the PO conversion and PC selectivity reached 99.7% and 99.1%, respectively. The catalytic impact correlates strongly with the doping amounts of Ga2O3 and Br, primarily due to the interaction of Ga2O3 with the surface of MCM-41, leading to the generation of more basic sites and, consequently, a greater abundance of alkali centers. As a nucleophilic reagent, Br functions synergistically with Ga2O3/MCM-41, augmenting the ring-opening rate of PO and improving the activation ability of CO2. The stability of the catalyst underwent evaluation, revealing a slight decrease in activity after repeated use. The reaction mechanism underlying PC synthesis catalyzed by Ga2O3/MCM-41-0.5 was speculated. [ABSTRACT FROM AUTHOR]

Bloodstream infections (BSIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) are potentially life-threatening and an urgent threat to public health. The present study aims to clarify the characteristics of carbapenemase-encoding and virulent plasmids, and their interactions with the host bacterium. A total of 425 Kp isolates were collected from the blood of BSI patients from nine Chinese hospitals, between 2005 and 2019. Integrated epidemiological and genomic data showed that ST11 and ST307 Kp isolates were associated with nosocomial outbreak and transmission. Comparative analysis of 147 Kp genomes and 39 completely assembled chromosomes revealed extensive interruption of acrR by ISKpn26 in all Kp carbapenemase-2 (KPC-2)-producing ST11 Kp isolates, leading to activation of the AcrAB-Tolc multidrug efflux pump and a subsequent reduction in susceptibility to the last-resort antibiotic tigecycline and six other antibiotics. We described 29 KPC-2 plasmids showing diverse structures, two virulence plasmids in two KPC-2-producing Kp, and two novel multidrug-resistant (MDR)-virulent plasmids. This study revealed a multifactorial impact of KPC-2 plasmid on Kp, which may be associated with nosocomial dissemination of MDR isolates.

Abstract Background The clinical characteristics of patients with confirmed 2019 novel coronavirus disease (COVID-19) in Jilin Province, China were investigated. Methods Clinical, laboratory, radiology, and treatment data of 41 hospitalized patients with confirmed COVID-19 were retrospectively collected. The population was stratified by disease severity as mild, moderate, or severe, based on guidelines of the National Health and Medical Commission of China. Results The 41 hospitalized patients with COVID-19 were studied, and the median age was 45 years (interquartile range [IQR], 31–53; range, 10–87 years) and 18 patients (43.9%) were female. All of the patients had recently visited Wuhan or other places (ie, Beijing, Thailand) or had Wuhan-related exposure. Common symptoms included fever (32[78%]) and cough (29[70.7%]). All patients were without hepatitis B/C virus hepatitis. CRP (C-reactive protein, 11.3 mg/L [interquartile range {IQR}, 2.45–35.2]) was elevated in 22 patients (53.7%), and cardiac troponin I (1.5 ng/mL [IQR, 0.8–5.0]) was elevated in 41 patients (100%). Chest computed tomographic scans showed bilateral ground glass opacity (GGO) or GGO with consolidation in the lungs of 27(65.9%) patients. 31(75.6%) patients had an abnormal electrocardiograph (ECG). Comparing the three groups, the levels of CRP and cardiac troponin I, GGO distribution in bilateral lungs, and electrocardiogram changes were statistically significant (p

ABSTRACT Two tet(X4)-positive Enterobacter cloacae isolates TECL_1 and TECL_2 were isolated from pigs in China. S1-PFGE and Southern blotting showed that tet(X4) located on plasmids in the size of ∼290 kb and ∼190 kb in TECL_1 and TECL_2, respectively. Conjugation experiment demonstrated that the tet(X4)-harboring plasmid can transfer from the donor strain TECL_1 and TECL_2 to the recipient strain Escherichia coli J53, and the tigecycline resistance of transconjugants was increased by 128-fold and 64-fold compared with E. coli J53, respectively. We obtained the complete plasmid sequence of pTECL_2-190k-tetX4 (190,185 bp) from E. cloacae TECL_2 and found that the plasmid was a hybrid plasmid with replicon types of IncFIA, IncHI1A and IncHI1B. We further analyzed 85 tet(X4)-carrying plasmids in the public database and clarified that pTECL_2-190k-tetX4-like plasmid was widespread in multiple species of Enterobacteriaceae. IMPORTANCE We identified two tet(X4)-positive E. cloacae isolates, which has not been previously reported. We obtained the complete sequence of pTECL_2-190k-tetX4 and found that it was a hybrid plasmid with multiple replicon types, including IncFIA, IncHI1A and IncHI1B. By comparing all the known tet(X4)-carrying plasmids, we found that pTECL_2-190k-tetX4-like plasmid has been disseminated across various species in China. Our study expanded the identification of tet(X4)-positive species and emphasized that pTECL_2-190k-tetX4-like plasmid has spread widely in various species.