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Background: The recent emergence and dissemination of high-level mobile tigecycline resistance Tet(X) challenge the clinical effectiveness of tigecycline, one of the last-resort therapeutic options for complicated infections caused by multidrug-resistant Gram-negative and Gram-positive pathogens. Although tet(X) has been found in various bacterial species, less is known about phylogeographic distribution and phenotypic variance of different genetic variants. Methods: Herein, we conducted a multiregional whole-genome sequencing study of tet(X)-positive Acinetobacter isolates from human, animal, and their surrounding environmental sources in China. The molecular and enzymatic features of tet(X) variants were characterized by clonal expression, microbial degradation, reverse transcription, and gene transfer experiments, while the tet(X) genetic diversity and molecular evolution were explored by comparative genomic and Bayesian evolutionary analyses. Results: We identified 193 tet(X)-positive isolates from 3846 samples, with the prevalence ranging from 2.3 to 25.3% in nine provinces in China. The tet(X) was broadly distributed in 12 Acinetobacter species, including six novel species firstly described here. Besides tet(X3) (n = 188) and tet(X4) (n = 5), two tet(X5) variants, tet(X5.2) (n = 36) and tet(X5.3) (n = 4), were also found together with tet(X3) or tet(X4) but without additive effects on tetracyclines. These tet(X)-positive Acinetobacter spp. isolates exhibited 100% resistance rates to tigecycline and tetracycline, as well as high minimum inhibitory concentrations to eravacycline (2–8 μg/mL) and omadacycline (8–16 μg/mL). Genetic analysis revealed that different tet(X) variants shared an analogous ISCR2-mediated transposon structure. The molecular evolutionary analysis indicated that Tet(X) variants likely shared the same common ancestor with the chromosomal monooxygenases that are found in environmental Flavobacteriaceae bacteria, but sequence divergence suggested separation ~ 9900 years ago (7887 BC), presumably associated with the mobilization of tet(X)-like genes through horizontal transfer. Conclusions: Four tet(X) variants were identified in this study, and they were widely distributed in multiple Acinetobacter spp. strains from various ecological niches across China. Our research also highlighted the crucial role of ISCR2 in mobilizing tet(X)-like genes between different Acinetobacter species and explored the evolutionary history of Tet(X)-like monooxygenases. Further studies are needed to evaluate the clinical impact of these mobile tigecycline resistance genes. [ABSTRACT FROM AUTHOR]

The selective feeding of plants and excavation of soil by small mammals, especially rodents, have important effects on plant-animal interactions, but few studies have explored these effects and their potential mechanisms. In the present study, large-scale enclosure manipulative experiments were performed to explore the effects of Brandt's vole (Lasiopodomys brandtii) on plant community composition and soil nutrients in Inner Mongolia, China. The results suggested that Brandt's vole significantly decreased community biomass compared to the control enclosure, reducing it by 21.42% at the end of the experiments. Further analysis showed that the rhizome grass biomass was significantly reduced by 86.82%, while the biomass of bunch grasses and forbs was higher in the vole enclosure by 18.35% and 49.64%, respectively. Furthermore, Brandt's vole significantly decreased species richness and the density, coverage, and importance value of the main forage species available. However, the soil main nutrient content and ammonium nitrogen mineralization rate were not significantly affected by the presence of Brandt's vole, whereas nitrification rate significantly increased in the vole enclosure. Finally, we conclude that Brandt's vole activity may affect the species' habitat quality by creating plant communities dominated by less preferred forage species. [ABSTRACT FROM AUTHOR]

Coal is the primary source of China's carbon emissions due to the energy structure and its resource endowment. This reality creates enormous pressure and impetus for low-carbon pathways of coal production and consumption. Based on a literature review on carbon emissions accounting methods, this paper builds a source-driven CO2 emissions accounting model for the coal development sector using the emissions factor method. Scenario analysis is employed to predict future carbon emission equivalents and to indicate possible implications for climate change mitigation in this sector. Carbon emissions from coal development are mainly derived from coal mine gas emissions, which yield 62% of the sector's total carbon emissions, followed by energy consumption. The recent decline in coal mining-driven CO2 emissions is mainly due to the strict deployment of coal mine gas and the changing structure of coal mines. The results from the scenarios suggest that the carbon emissions reduction potential will largely be determined by technology innovation in the coal mine gas industry. Policy implications for further addressing carbon emissions from the supply side of the coal industry include improvements in energy efficiency and coal mine gas extraction and utilization. [ABSTRACT FROM AUTHOR]

Purpose. As we all know, curative resection remains the only effective treatment for hepatocellular cancer (HCC). However, systemic inflammatory response syndrome always correlates with surgery, which may impose an impact on the clinical outcome of HCC patients who had undergone curative treatment. The present study is aimed at exploring the correlation between perioperative inflammatory mediators and recurrence risk of HCC. Methods. This study retrospectively included 157 histologically confirmed single HCC patients (88 patients developed HCC again) who had received radical hepatectomy between January 2016 and May 2018 at the Department of Hepatobiliary Surgery, the People's Liberation Army General Hospital (PLAGH), China. The cut-off values for predicting recurrence were determined by receiver operating characteristic (ROC) curve analysis with estimation of the Youden index. Recurrence-free survival (RFS) was assessed using the Kaplan-Meier method, and the difference was compared between groups by the log-rank test. Univariate/multivariate analysis was performed to identify independent risk factors of postoperative tumor recurrence. Results. The perioperative serum IL1, IL2, and IL10 levels showed no difference between groups, whereas the serum IL6, IL8, and TNF-α levels showed significant differences between groups. High preoperative serum IL6, IL8, and TNF-α levels were significantly associated with shorter RFS. Multivariate analysis revealed that preoperative serum IL6>8.45 pg/ml, preoperative serum IL8>68 pg/ml, preoperative serum TNF−α>14.9 pg/ml, microvascular invasion (MVI), and maximum tumor size>6 cm were independent predictors of RFS. Conclusions. The present study confirmed that high preoperative serum IL6, IL8, and TNF-α levels were distinctly correlated with the postoperative tumor recurrence risk of HCC patients. [ABSTRACT FROM AUTHOR]

In this study, we reported the occurrence of eight organophosphorus pesticides (OPPs) in the East China Sea. Forty samples were collected and analysed with a high volume solid phase extraction method (Hi-throat/Hi-volume SPE) in the early summer of 2020. All the target OPPs were detected in the surface water at one or more stations in the East China Sea, and the concentrations of ΣOPPs were in the range 0.0775–3.09 ng/L (mean: 0.862 ± 0.624 ng/L). Terbufos sulfone and fenthion were the main pollutants in this area, probably resulting from pesticide use in China and other countries. The off-shore input from coastal regions was suggested to be a major source of OPP pollution in the East China Sea, and the movement of ocean currents played an important role in their transportation because around 0.86 t OPPs passed through the Tsushima Strait from the East China Sea each month. An ecological risk assessment showed that these OPPs presented a high risk to species in the East China Sea, whereas they posed no health risk to humans under both the median and high exposure scenario. [Display omitted] • Hi-throat/Hi-volume SPE was suitable for collecting and analyzing OPPs in seawater. • The total concentration of eight OPPs was 0.0775–3.09 ng/L in the East China Sea. • Around 0.86 t OPPs entered the Japan Sea from the East China Sea per month. • There was a high ecological risk of OPPs to organisms in the East China Sea. Hi-throat/Hi-volume SPE is effective in the collection and analysis of OPPs in seawater, and there is emerging risk of OPP exposure to organisms in the East China Sea. [ABSTRACT FROM AUTHOR]

The migration and interaction of water and gas in coal plays an important role in achieving high-performance recovery of coalbed methane (CBM). While a significant amount of fracturing fluid is injected into the reservoir to enhance the production of CBM, the effect of the imbibed liquid on the gas transport process remains poorly understood. To better understand the impact on well productivity after fracturing fluid invasion, we carried out experimental investigations on dynamic imbibition of water, and resulting matrix permeability changes, using core plug samples of coal from the Qinshui, Ordos and Junggar basins in China. The imbibition process is divided into a quick stage followed by a slow stage: the former occurs in seepage pores with a higher imbibition rate and larger imbibition time-exponent than the latter, which occurs in adsorption pores. Capillary and frictional resistance forces control the spontaneous imbibition of coals. Water movement during gas flooding has a similar imbibition rate and imbibition resistance to the slow stage of spontaneous imbibition, suggesting that the water migration process moves from larger seepage pores to smaller adsorption pores, and this is the main reason for a change in gas permeability. Gas permeability can seemingly be reduced because of two combined mechanisms: 1) occupation of the gas flow path by water in seepage pores; and 2) matrix swelling induced by water adsorption in adsorption pores. In contrast, the changing gas slippage factor can lead to an improvement in gas permeability. Coupling these three factors, we propose a modified permeability model that can be used to evaluate the influence of water on gas permeability and then to estimate the change in gas permeability during hydro-fracturing of a CBM reservoir. • 2D NMR time-profile was firstly used for visualization of dynamic imbibition process. • Investigated how the influence of water imbibition on gas permeability of coal. • Investigated how water migration from a hydro-fracture into coal matrix. • Investigated how water migration in coal matrix during flowback. • Proposed a permeability model that is a function of different water saturation. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is emerging as a significant cause of human and animal disease worldwide. A total of 3400 samples were collected from animal farms and adjacent environments in China. The bla L1 and bla L2 genes were identified using whole genome sequence analyses and examined by phylogenetics. Isolates were also tested for susceptibility to 18 antibiotics. We isolated 118 strains of S. maltophilia from 3400 samples. The positive rates of bla L1 and bla L2 genes were 75% (89/118) and 22% (26/118) and we identified 11 L1 and 6 L2 amino acid sequence variants. S. maltophilia has at least two inducible β-lactamases (L1 and L2) that can hydrolyze almost all classes of β-lactams and these genes are suspected to confer carbapenem resistance. This represents a significant public health threat especially for hospitalized patients. We conducted a molecular surveillance study on the prevalence and characteristics of the bla L1 and bla L2 genes of S. maltophilia. • The strains of 118 S. maltophilia with high levels resistance to carbapenems. • Seventy-seven L1 and eighty L2 variants were discovered. • The 8 L1 and 1 L2 novel variants of S. maltophilia were isolated. • The cloning of novel variants MICs showed 0.125 to 32 μg/mL to MEM, IMP, ERT, CTX, CZA. • The MICs of cloned novel variants showed 2–2000-fold greater than the negative control strain. • The clonal S. maltophilia in human-animal-environment can pose a potential threat to public health. [ABSTRACT FROM AUTHOR]

Sewage sludge (SS) is commonly used as agricultural fertilizer worldwide. However, the toxic metal(loid)s in SS raises concerns about soil contamination and the potential risks to human health. This study, conducted since 2007 on the North China Plain, examines the impact of SS use on crops. An experiment was designed with five treatments: conventional fertilization (CK) and four levels of SS application (W1, W2, W3, and W4: 4.5, 9.0, 18.0, and 36.0 t ha -1 , respectively). Soil concentrations of eight toxic metal(loid)s (Zn, Cu, Cr, Cd, Ni, Pb, As, and Hg) were analyzed to assess pollution risk using various indices. Health risks associated with maize and wheat grains were also evaluated. Additionally, the impact of long-term SS application on crop yield, soil quality, and human health within a wheat-maize rotation system was examined. SS application increased wheat and maize yields by 5.37 to 19.08 % and 6.97 to 17.94 %, respectively, across treatments W2 to W4. Despite the toxic metal(loid)s in the grains remaining within safe limits, their concentrations showed an upward trend, especially under the W4 treatment. Moreover, SS application significantly increased the soil Zn, Cu, Cr, Cd, Pb, and Hg levels (P < 0.05) without exceeding the national standards. The geo-accumulation index values revealed rising pollution levels for Zn, Cu, Cd, and Hg, which shifted from no contamination to moderate contamination and then to moderate-to-high contamination, yet the overall pollution level remained safe. Soil ecological risks increased from moderate to serious, with Hg posing the greatest risk, particularly under the W4 treatment. Long-term crop intake from the area significantly exposed children and adults to As, contributing 42.12 % and 34.62 % to hazard index (HI), respectively. The HI values for toxic metal(loid)s in these grains surpassed one in both age groups, suggesting health risks from long-term SS cultivated crops., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The recent emergence of plasmid-mediated tigecycline resistance gene tet(X) has challenged the clinical effectiveness of tigecycline as a last-resort treatment option. During 2017-2018, 336 fecal samples from sick ducks, pigs, chickens and geese in Guangdong, China, were screened for tet(X)-positive Acinetobacter baumannii strains. Their activities on tetracyclines were determined by microbiological degradation and mass spectrometry, followed by susceptibility testing, sequence typing, gene transfer, molecular location and genomic DNA sequencing analyses. A total of 10 tet(X)-positive A. baumannii strains were isolated from ducks and chickens, including eight plasmid-borne tet(X5)-positive and two chromosomal tet(X6)-positive isolates. All of them exhibited good degradation activities on tetracyclines by hydroxylation at C11a and were multidrug-resistant to tigecycline, tetracycline, florfenicol, ciprofloxacin and trimethoprim/sulfamethoxazole. Genetically, they belonged to two sequence types (ST355, n = 8; ST1980, n = 2) that were consistent with their pulsotypes, revealing a clonal spread of ST355 A. baumannii. An ISCR2- or IS26-mediated tet(X) transposition structure, homologous to those of clinical A. baumannii strains, was also identified and ISCR2 could transfer tet(X5) into the recipient Acinetobacter baylyi ADP1 at a frequency of (1.8 ± 0.3)×10 -6 . Therefore, more efforts are needed to evaluate the clinical impact of these tigecycline resistance genes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Tigecycline serves as one of the antibiotics of last resort to treat multidrug-resistant (including carbapenem-resistant) pathogens. However, the recently emerged plasmid-mediated tigecycline resistance mechanism, Tet(X), challenges the clinical efficacy of this class of antibiotics. In this study, we detected 180 tet (X)-harboring Acinetobacter isolates (8.9%, n  = 180) from 2,018 samples collected from avian farms and adjacent environments in China. Eighteen tet (X)-harboring isolates (10.0%) were found to cocarry the carbapenemase gene bla NDM-1 , mostly from waterfowl samples (94.4%, 17/18). Interestingly, among six Acinetobacter strains, tet (X) and bla NDM-1 were found to colocalize on the same plasmids. Moreover, whole-genome sequencing (WGS) revealed a novel orthologue of tet (X) in the six isolates coharboring tet (X) and bla NDM-1 Inverse PCR suggested that the two tet (X) genes form a single transposable unit and may be cotransferred. Sequence comparison between six tet (X)- and bla NDM-1 -coharboring plasmids showed that they shared a highly homologous plasmid backbone even though they were isolated from different Acinetobacter species (three from Acinetobacter indicus , two from Acinetobacter schindleri species in China. Emergence and spread of such plasmids and strains are of great clinical concern, and measures must be implemented to avoid their dissemination.Acinetobacter lwoffii ) from various sources and from different geological regions, suggesting the horizontal genetic transfer of a common tet (X)- and bla NDM-1 -coharboring plasmid among Acinetobacter species in China. Emergence and spread of such plasmids and strains are of great clinical concern, and measures must be implemented to avoid their dissemination., (Copyright © 2020 American Society for Microbiology.)

Tigecycline is one of the last-resort antibiotics to treat complicated infections caused by both multidrug-resistant Gram-negative and Gram-positive bacteria 1 . Tigecycline resistance has sporadically occurred in recent years, primarily due to chromosome-encoding mechanisms, such as overexpression of efflux pumps and ribosome protection 2,3 . Here, we report the emergence of the plasmid-mediated mobile tigecycline resistance mechanism Tet(X4) in Escherichia coli isolates from China, which is capable of degrading all tetracyclines, including tigecycline and the US FDA newly approved eravacycline. The tet(X4)-harbouring IncQ1 plasmid is highly transferable, and can be successfully mobilized and stabilized in recipient clinical and laboratory strains of Enterobacteriaceae bacteria. It is noteworthy that tet(X4)-positive E. coli strains, including isolates co-harbouring mcr-1, have been widely detected in pigs, chickens, soil and dust samples in China. In vivo murine models demonstrated that the presence of Tet(X4) led to tigecycline treatment failure. Consequently, the emergence of plasmid-mediated Tet(X4) challenges the clinical efficacy of the entire family of tetracycline antibiotics. Importantly, our study raises concern that the plasmid-mediated tigecycline resistance may further spread into various ecological niches and into clinical high-risk pathogens. Collective efforts are in urgent need to preserve the potency of these essential antibiotics.

Plasmid-mediated antimicrobial resistance has emerged as one of the principal global issues, posing significant threats to public health. Herein, we reported a mobile tigecycline resistance mechanism Tet(X4) on both plasmid and chromosome in Escherichia coli strains from migratory birds in China. Besides tigecycline, these tet (X4)-positive strains also exhibited elevated MICs to the FDA newly approved tetracycline antibiotics, eravacycline (4 µg/ml) and omadacycline (8 µg/ml). Worrisomely, the tet (X4)-carrying plasmids and chromosome also shared high homology with the plasmids from human. Taken together, Tet(X4) represents another emerging antimicrobial threat and collective efforts from different sectors are needed to control its further spread.

Objective: To evaluate the potential implications of the genetic variability of angiotensin converting enzyme, angiotensinogen and angiotensin II type 1 receptor gene for essential hypertension in Tibetan., Methods: A case-control study was conducted in 173 hypertensive individuals and 193 individuals with normal blood pressure. Multiple logistic regression analyses were used to estimate the risks of developing hypertension for different genotypes, and haplotype analyses of the angiotensinogen gene were used to determine the association between two-locus angiotensinogen gene polymorphisms and hypertension., Results: As to the risk to high blood pressure and high systolic pressure, women with MM genotype were 7.7 (95% CI: 1.3-20.5) and 8.7 (95% CI: 1.8-20.1) times higher than those with TT genotype after adjustment for age and body mass index. Haplotype frequencies for M235T and G-6A were significantly different between hypertensive individuals and controls, which indicated an association of angiotensinogen gene haplotypes with hypertension, and a significant association of 235T/-6A haplotype with hypotensive effect., Conclusion: Our results suggest that angiotensinogen gene 235MM is a predictor for hypertension development in Tibetan women but not in men, and may exert its hypertensive effect on linkage disequilibrum with a possible function locus of G-6A.

Objective: To clarify whether A1166C polymorphism of the angiotensin II type 1 receptor (AT(1)R) gene is associated with susceptibility to essential hypertension in Han, Tibetan and Yi populations in China., Methods: This study involved 302 normotensive and 446 hypertensive subjects. The polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism in genomic DNA. The data were analyzed by ANCOVA, chi-square test, and multiple logistic regression., Results: In normotensive controls, the A1166 allele frequencies were 0.979, 0.939 and 0.965 in Han, Tibetan and Yi participants, respectively. There was no significant intergroup variation in frequency of the allele in normotensives (chi-square=4.166, P=0.125). The frequency of the A1166 allele in Tibetan male hypertensives was significantly higher than that in normotensives (chi-square=11.46, P=0.001). There was no significant difference in A1166C genotype distribution and allele frequency between normotensives and hypertensives either in the Han (P=0.465) or Yi (P=0.357) populations. Body mass index in the Han and Yi populations (P=0.0001), age in the Tibetan and Yi populations (P=0.0001), and AA genotype in the Tibetan male population (P=0.0034) all were independent risk factors for hypertension. Diastolic blood pressure levels were significantly higher in Tibetan male subjects with the AA genotype than in those with the AC+CC genotype (P=0.0040)., Conclusion: The A1166 allele is very common in Han, Tibetan and Yi populations, approximately 1.35-fold more common than in Caucasians. The A1166 allele of the AT(1)R gene may be a predisposing factor for essential hypertension in Tibetan males. A1166C polymorphism of the AT(1)R gene is probably not involved in the pathogenesis of essential hypertension in Han and Yi populations.