Topological valley Hall polariton condensation

A photonic topological insulator features robust directional propagation and immunity to defect perturbations of the edge/surface state. Exciton-polaritons, that is, the hybrid quasiparticles of excitons and photons in semiconductor microcavities, have been proposed as a tunable nonlinear platform for emulating topological phenomena. However, mainly due to excitonic material limitations, experimental observations so far have not been able to enter the nonlinear condensation regime or only show localized condensation in one dimension. Here we show a topological propagating edge state with polariton condensation at room temperature and without any external magnetic field. We overcome material limitations by using excitonic CsPbCl3 halide perovskites with a valley Hall lattice design. The polariton lattice features a large bandgap of 18.8 meV and exhibits strong nonlinear polariton condensation with clear long-range spatial coherence across the critical pumping density. The geometric parameters and material composition of our nonlinear many-body photonic system platform can in principle be tailored to study topological phenomena of other interquasiparticle interactions.

Alpha-tocopherol inhibits ferroptosis and promotes neural function recovery in rats with spinal cord injury via downregulating Alox15

Spinal cord injury (SCI) is a type of central nervous system (CNS) injury in which ferroptosis is becoming a promising target for treatment. Alpha-tocopherol (Vitamin E, Vit E) is a compound with anti-ferroptosis activity. The mechanism of alpha-tocopherol in regulating ferroptosis after SCI has not been deeply studied. In this study, rats with SCI were treated by Alpha-tocopherol based on bioinformatic analysis and molecular docking prediction. Behavioral tests and histological findings showed that Alpha-tocopherol promoted neural function recovery and tissue repairment in rats with SCI. Subsequently, regulatory effects of Alpha-tocopherol on Alox15 and ferroptosis were detected and then localized by immunofluorescence. In vitro, alpha-tocopherol improved the ROS accumulation, iron overload, lipid peroxidation and mitochondrial dysfunction. The effects of Alpha-tocopherol on the expression of Alox15, Ptgs2 and 4Hne were validated in vitro. Finally, the inhibitory effects of Alpha-tocopherol on Alox15 and ferroptosis were weakened by the mutation of 87th residue of Alox15. In summary, alpha-tocopherol could alleviate SCI-induced ferroptosis by downregulating Alox15 to promote neural function recovery in rats with SCI. Findings in this study could help further our understanding on SCI-induced ferroptosis and provide a novel insight for treating SCI.

Restore polder and aquaculture enclosure to the lake: Balancing environmental protection and economic growth for sustainable development

The restoration of lakes and their buffer zones is crucial for understanding the intricate interplay between human activities and natural ecosystems resulting from the implementation of environmental policies. In this study, we investigated the ecological restoration of shallow lakes and buffer zones in the Yangtze-Huaihe River Basin, specifically focusing on the removal of polder and aquaculture enclosure areas within the lakes. By examining data from eight shallow lakes and their corresponding buffer zones, encompassing lake morphology, water quality parameters, and land use/land cover (LULC) data spanning from 2008 to 2022, which shed light on the complex relationships involved. During the process of restoring polder and aquaculture enclosure areas, we observed a general decrease in the extent of polders and aquaculture enclosures within the lakes. Notably, the removal of aquaculture enclosures had a more pronounced effect (reduction rate of 83.37 %) compared to the withdrawal of polders (reduction rate of 48.76 %). Linear regression analysis revealed a significant decrease in the concentrations of seven water quality parameters, including COD, CODMn, TN, TP, NH3-N, Chl-a, and F, while pH and DO factors exhibit a distinct increasing trend. The results of redundancy analysis and Pearson correlation analysis demonstrated significant correlations between the area of polders and aquaculture enclosures and the changes in lake water quality. Encouragingly, the withdrawal of polders and the removal of aquaculture enclosures had a positive impact on the lake water quality improvement. In contrast, the LULC in the buffer zones of the lakes experienced a gradual decline owing to land degradation, resulting in a reduction in ecosystem service value (ESV). These results offer valuable support for policymakers in their endeavors to restore lake water quality, mitigate the degradation of buffer zones land, and promote the sustainable development of land and water resources.

Large-scale bacterial genomic and metagenomic analysis reveals Pseudomonas aeruginosa as potential ancestral source of tigecycline resistance gene cluster tmexCD-toprJ

BACKGROUND

The global dissemination of the multidrug resistance efflux pump gene cluster tmexCD-toprJ has greatly weakened the effects of multiple antibiotics, including tigecycline. However, the potential origin and transmission mechanisms of the gene cluster remain unclear.

METHODS

Here, we concluded a comprehensive bioinformatics analysis on integrated 73,498 bacterial genomes, including Pseudomonas spp., Klebsiella spp., Aeromonas spp., Proteus spp., and Citrobacter spp., along with 1,152 long-read metagenomic datasets to trace the origin and propagation of tmexCD-toprJ.

RESULTS

Our results demonstrated that tmexCD-toprJ was predominantly found in Pseudomonas aeruginosa sourced from human hosts in Asian countries and North American countries. Phylogenetic and genomic feature analyses showed that tmexCD-toprJ was likely evolved from mexCD-oprJ of some special clones of P. aeruginosa. Furthermore, metagenomic analysis confirmed that P. aeruginosa is the only potential ancestral bacterium for tmexCD-toprJ. A putative mobile genetic structure harboring tmexCD-toprJ, int-int-hp-hp-tnfxB-tmexCD-toprJ, was the predominant genetic context of tmexCD-toprJ across various bacterial genera, suggesting that the two integrase genes play a pivotal role in the horizontal transmission of tmexCD-toprJ.

CONCLUSIONS

Based on these findings, it is almost certain that the tmexCD-toprJ gene cluster was derived from P. aeruginosa and further spread to other bacteria.

Resensitizing tigecycline- and colistin-resistant Escherichia coli using an engineered conjugative CRISPR/Cas9 system

Tigecycline and colistin were referred to as the "last resort" antibiotics in defending against carbapenem-resistant, Gram-negative bacterial infections, and are currently widely used in clinical treatment. However, the emergence and prevalence of plasmid-mediated tet(X4) and mcr-1 genes pose a serious threat to the therapeutic application of tigecycline and colistin, respectively. In this research, a tigecycline- and colistin-resistant bacteria resensitization system was developed based on efficient and specific DNA damage caused by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Associated Protein 9 (Cas9) nucleases. A conjugation method was used to deliver the resensitization system, which harbors two single-guide RNAs targeting tet(X4) and mcr-1 genes and constitutively expressed Cas9. The conjugation efficiency was nearly 100% after conjugation condition optimization in vitro, and the resensitivity efficiency for clinical isolates was over 90%. In addition, when performing resensitization in vivo, the resistance marker was replaced with a glutamate-based, chromosomal, plasmid-balanced lethal system to prevent the introduction of additional resistance genes in clinical settings, making this strategy a therapeutic approach to combat the in vivo spread of antibiotic resistance genes (ARGs) among bacterial pathogens. As a proof of concept, this resensitive system can significantly decrease the counts of tigecycline- and colistin-resistant bacteria to 1% in vivo. Our study demonstrates the efficacy and adaptability of CRISPR-Cas systems as powerful and programmable antimicrobials in resensitizing tet(X4)- and mcr-1-mediated, tigecycline- and colistin-resistant strains, and opens up new pathways for the development of CRISPR-based tools for selective bacterial pathogen elimination and precise microbiome composition change.

IMPORTANCE

The emergence of plasmid-encoded tet(X4) and mcr-1 isolated from human and animal sources has affected the treatment of tigecycline and colistin, and has posed a significant threat to public health. Tigecycline and colistin are considered as the "last line of defense" for the treatment of multidrug-resistant (MDR) Gram-negative bacterial infections, so there is an urgent need to find a method that can resensitize tet(X4)-mediated tigecycline-resistant and mcr-1-mediated colistin-resistant bacteria. In this study, we developed a glutamate-based, chromosomal, plasmid-balanced lethal conjugative CRISPR/Cas9 system, which can simultaneously resensitize tet(X4)-mediated tigecycline-resistant and mcr-1-mediated colistin-resistant Escherichia coli. The counts of tigecycline- and colistin-resistant bacteria decreased to 1% in vivo after the resensitization system was administered. This study opens up new pathways for the development of CRISPR-based tools for selective bacterial pathogen elimination and precise microbiome composition change.

Determinants of depressive symptoms at individual, school and province levels: a national survey of 398,520 Chinese children and adolescents

OBJECTIVES

The aims of this study were to describe the national distribution of depressive symptoms in Chinese children and adolescents, to examine the determinants of depressive symptoms at individual, school and province levels and to assess the gender and age differences in the effect of school factors on depressive symptoms.

STUDY DESIGN

This was a national cross-sectional study.

METHODS

A school-based online survey was conducted in mainland China from between December 1, 2021, and January 1, 2022. A total of 398,520 eligible participants were included in the analysis. School-level data were drawn from students, headteachers and Baidu Maps, and province-level data were obtained from the national human development report. The Patient Health Questionnaire-2 was used to measure depressive symptoms.

RESULTS

Areas with the highest mean scores for depressive symptoms were in the northeastern, inner central and southwestern regions of China. At the individual level, younger age, male sex, being an only child, Han ethnicity, lower body mass index, more days of exercise, less drinking and smoking behaviours, higher subjective family socio-economic status (SES) and popularity in school were related to fewer depressive symptoms; however, objective family SES and maternal education were not related to fewer depressive symptoms. The school-level variables of public status, psychological activities and psychological courses and province-level variable of higher Human Development Index were associated with fewer depressive symptoms. The effect of psychological courses and activities on depressive symptoms was greater in females.

CONCLUSIONS

The results showed multilevel factors related to depressive symptoms and emphasised the importance of implementing school-based psychological activities to ameliorate depressive symptoms in Chinese children and adolescents across age and gender.

Transformation process and phytotoxicity of sulfamethoxazole and N4-acetyl-sulfamethoxazole in rice

Sulfonamide antibiotics, extensively used in human and veterinary therapy, accumulate in agroecosystem soils through livestock manure and sewage irrigation. However, the interaction between sulfonamides and rice plants remains unclear. This study investigated the transformation behavior and toxicity of sulfamethoxazole (SMX) and its main metabolite, N4-acetyl-sulfamethoxazole (NASMX) in rice. SMX and NASMX were rapidly taken up by roots and translocated acropetally. NASMX showed higher accumulating capacity, with NASMX concentrations up to 20.36 ± 1.98 μg/g (roots) and 5.62 ± 1.17 μg/g (shoots), and with SMX concentrations up to 15.97 ± 2.53 μg/g (roots) and 3.22 ± 0.789 μg/g (shoots). A total of 18 intermediate transformation products of SMX were identified by nontarget screening using Orbitrap-HRMS, revealing pathways such as deamination, hydroxylation, acetylation, formylation, and glycosylation. Notably, NASMX transformed back into SMX in rice, a novel finding. Transcriptomic analysis highlights the involvements of cytochrome P450 (CYP450), acetyltransferase (ACEs) and glycosyltransferases (GTs) in these biotransformation pathways. Moreover, exposure to SMX and NASMX disrupts TCA cycle, amino acid, linoleic acid, nucleotide metabolism, and phenylpropanoid biosynthesis pathways of rice, with NASMX exerting a stronger impact on metabolic networks. These findings elucidate the sulfonamides' metabolism, phytotoxicity mechanisms, and contribute to assessing food safety and human exposure risk amid antibiotic pollution.

Mechanistic regulation of FOXO transcription factors in the nucleus

FOXO proteins represent evolutionarily conserved transcription factors (TFs) that play critical roles in responding to various physiological signals or pathological stimuli, either through transcription-dependent or -independent mechanisms. Dysfunction of these proteins have been implicated in numerous diseases, including cancer. Although the regulation of FOXO TFs shuttling between the cytoplasm and the nucleus has been extensively studied and reviewed, there's still a lack of a comprehensive review focusing on the intricate interactions between FOXO, DNA, and cofactors in the regulation of gene expression. In this review, we aim to summarize recent advances and provide a detailed understanding of the mechanism underlying FOXO proteins binding to target DNA. Additionally, we will discuss the challenges associated with pharmacological approaches in modulating FOXO function, and explore the dynamic association between TF, DNA, and RNA on chromatin. This review will contribute to a better understanding of mechanistic regulations of eukaryotic TFs within the nucleus.

Spatial and temporal variation in lake macroinvertebrate communities is decreased by eutrophication

Eutrophication impacts freshwater ecosystems and biodiversity across the world. While temporal monitoring has shown changes in the nutrient inputs in many areas, how spatial and temporal beta diversity change along the eutrophication gradient under a changing context remains unclear. In this regard, analyses based on time series spanning multiple years are particularly scarce. We sampled benthic macroinvertebrates in 32 sites across three lake habitat types (MACROPHYTE, OPEN WATER, PHYTOPLANKTON) along the eutrophication gradient of Lake Taihu in four seasons from 2007 to 2019. Our purpose was to identify the relative contributions of spatial and temporal dissimilarity (i.e., inter-annual dissimilarity and seasonal dissimilarity) to overall benthic biodiversity. We also examined spatio-temporal patterns in community assembly mechanisms and how associated variation in benthic macroinvertebrate communities responded to nutrient indicators. Results showed that eutrophication caused macroinvertebrate community homogenization both along spatial and temporal gradients. Though spatial variability dominated the variation of species richness, abundance and community dissimilarity, seasons within years dissimilarity, inter-annual dissimilarity and seasonal dissimilarity were much more sensitive to eutrophication. Moreover, eutrophication inhibited a strong environmental control in benthic macroinvertebrate community assembly, including a dominant role of deterministic process in the spatial variation of macroinvertebrate communities and transition from stochastic to deterministic process in the temporal assembly of macroinvertebrate communities along the eutrophication gradient. In addition, some sites in PHYTOPLANKTON habitats showed similar spatial dissimilarity and spatial SES as sites in MACROPHYTE habitats, and the decreased spatial dissimilarity of three habitats implying that lake ecosystem recovery projects have achieved their goal at least to a certain degree.

Study of Iron Complex Photosensitizer with Hollow Double-Shell Nano Structure Used to Enhance Ferroptosis and Photodynamic Therapy

Ferroptosis therapy, which uses ferroptosis inducers to produce lethal lipid peroxides and induce tumor cell death, is considered a promising cancer treatment strategy. However, challenges remain regarding how to increase the accumulation of reactive oxygen species (ROS) in the tumor microenvironment (TME) to enhance antitumor efficacy. In this study, a hyaluronic acid (HA) encapsulated hollow mesoporous manganese dioxide (H-MnO2 ) with double-shell nanostructure is designed to contain iron coordinated cyanine near-infrared dye IR783 (IR783-Fe) for synergistic ferroptosis photodynamic therapy against tumors. The nano photosensitizer IR783-Fe@MnO2 -HA, in which HA actively targets the CD44 receptor, subsequently dissociates and releases Fe3+ and IR783 in acidic TME. First, Fe3+ consumes glutathione to produce Fe2+ , which promotes the Fenton reaction in cells to produce hydroxyl free radicals (·OH) and induce ferroptosis of tumor cells. In addition, MnO2 catalyzes the production of O2 from H2 O2 and enhances the production of singlet oxygen (1 O2 ) by IR783 under laser irradiation, thus increasing the production and accumulation of ROS to provide photodynamic therapy. The highly biocompatible IR783-Fe@MnO2 -HA nano-photosensitizers have exhibited tumor-targeting ability and efficient tumor inhibition in vivo due to the synergistic effect of photodynamic and ferroptosis antitumor therapies.

Prognostic value of geriatric nutritional risk index and prognostic nutritional index in hepatocellular carcinoma

BACKGROUND

The geriatric nutritional risk index (GNRI) and prognostic nutritional index (PNI) are considered prognostic factors for several cancers. This study aimed to investigate the relationship between the GNRI and PNI for survival outcomes in patients with hepatocellular carcinoma (HCC).

METHODS

We retrospectively analyzed 1666 patients with HCC who underwent hepatectomy. Restricted cubic spline regression was used to analyze the relationship between the GNRI and PNI for recurrence and mortality. Cox proportional hazards regression analysis was used to evaluate the risk factors associated with overall survival (OS) and recurrence-free survival (RFS). Interaction analysis was performed to investigate the comprehensive effects of the GNRI, PNI, and subgroup parameters on the prognosis of patients with HCC.

RESULTS

The risks of death and recurrence decreased rapidly and gradually stabilized as the GNRI and PNI scores increased. Patients with lower GNRI and PNI scores had significantly shorter OS and RFS rates than those with higher scores. Multivariate analysis showed that high GNRI [HR and 95%CI = 0.77 (0.70-0.85), P < 0.001] and PNI [HR and 95%CI = 0.77 (0.70-0.86), P < 0.001] scores were associated with decreased mortality risk. This trend was maintained by confounding variables in adjusted models despite partial interactions with clinical factors. The combined GNRI and PNI analysis showed that HCC patients with high GNRI and PNI had longer OS and RFS.

CONCLUSIONS

The GNRI and PNI showed good survival predictions in patients with HCC. Combining the GNRI with PNI may help predict the prognosis of patients (age>18 years) with HCC after hepatectomy.

Conjugative plasmids facilitate the transmission of tmexCD2-toprJ2 among carbapenem-resistant Klebsiella pneumoniae

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a great threat to global public health. The emergence of tmexCD-toprJ greatly weakened the efficacy of tigecycline in the treatment of CRKP infections. In this study, we did a comprehensive investigation of the prevalence and genomic features of tmexCD-toprJ in clinical CRKP from 2018 to 2020 in Henan province, China. The results demonstrated tmexCD-toprJ was at a low prevalence in CRKP from patients (7/2031, 0.34 %). Among the seven tmexCD-toprJ positive CRKP, KP18-29 that carried tmexCD1-toprJ1, blaNDM-1 and mcr-8.2 was resistant to tigecycline, carbapenem and colistin simultaneously. While, tmexCD2-toprJ2 together with one or two carbapenemase genes were detected in the remaining strains. Four strains (KP18-231, KP18-2110-2, KP19-3023 and KP19-3088) isolated at different times but shared the same sequence type (ST) 2667 exhibited high genomic similarity, indicating the clonal dissemination of CRKP ST2667 co-producing KPC-2 and TMexCD-TOprJ. Notably, conjugative transmission of the IncFrepB(R1701) plasmid co-harboring tmexCD2-toprJ2 and blaKPC-2 among clinical CRKP isolates belonging to different STs (ST2667, ST978 and ST147) revealed further propagation of tmexCD-toprJ among K. pneumoniae. Such IncFrepB(R1701) plasmids pose a substantial threat to public health due to their mobile resistance to both tigecycline and carbapenem. Online data mining showed isolates carried both carbapenemase genes and tmexCD-toprJ were dominantly isolated from humans, and isolates of animal origins usually carried mcr genes and tmexCD-toprJ, suggesting that these critical resistance genes co-existed in diverse niches. Global surveillance of K. pneumoniae co-harboring tmexCD-toprJ and mcr/carbapenemase genes in various settings with a One Health strategy was warranted.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Construction and assessment of an indicator system of stream conditions in a typical mountain landscape in Northeast China

Stream ecosystem health assessments are crucial for the effective management of aquatic ecosystem service functions and the assessment of anthropogenic and climatic impacts on aquatic ecosystems. However, there is still a lack of comprehensive assessment methods based on complete ecosystem structures. This study improved an ecological health assessment system, which consists of 13 indicators based on ecosystem structure. The assessment system was applied to 30 streams on Changbai Mountain. The results showed that the comprehensive index of stream health (ISH) in Changbai Mountain was relatively high, and the ISH increased with the elevation gradient. The dominant factors controlling the ecosystem health level were water pH, water flow, vegetation coverage, total phosphorus (TP), and vegetation diversity index. All these results indicated that the damage caused by excessive deforestation and farmland occupation in recent years has not been fully reversed and that human disturbance from tourism may be the main reason for the low stream health at lower elevations. Our results suggest that the key to future work is to increase quantitative research on disturbance sensitivity and to develop economically viable restoration measures.

Climate-associated variation in the drivers of benthic macroinvertebrate species-area relationships across shallow freshwater lakes

The island species-area relationship (ISAR) describes how species richness increases with increasing area of a given island or island-like habitat, such as freshwater lakes. While the ISAR is one of the most common phenomena observed in ecology, there is variation in both the form of the relationship and its underlying mechanisms. We compiled a global data set of benthic macroinvertebrates from 524 shallow freshwater lakes, ranging from 1 to 293,300 ha in area. We used individual-based rarefaction to determine the degree to which ISAR was influenced by mechanisms other than passive sampling (larger islands passively sample more individuals from the regional pool and, therefore, have more species than smaller islands), which would bias results away from expected relationships between rarefied species richness (and other measures that capture relative abundances) and lake area. We also examined how climate may alter the shape of the ISARs. We found that both rarefied species richness (the number of species standardized by area or number of individuals) and a measure of evenness emphasizing common species exhibit shallow slopes in relationships with lake area, suggesting that the expected ISARs in these lakes most likely result from passive sampling. While there was considerable variation among ISARs across the investigated lakes, we found an overall positive rarefied ISAR for lakes in warm (i.e. tropical/subtropical) regions (n = 195), and in contrast, an overall negative rarefied ISAR in cool (i.e. north temperate) lakes (n = 329). This suggested that mechanisms beyond passive sampling (e.g. colonization-extinction dynamics and/or heterogeneity) were more likely to operate in warm lakes. One possible reason for this difference is that the area-dependent intensity of fish predation, which can lead to flatter ISARs, is weaker in warmer relative to cooler lakes. Our study illustrates the importance of understanding both the pattern and potential processes underlying the ISARs of freshwater lakes in different climatic regions. Furthermore, it provides a baseline for understanding how further changes to the ecosystem (i.e. in lake area or climate) might influence biodiversity patterns.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Case report: hepatic arterial infusion chemotherapy combined with sintilimab and lenvatinib for conversion therapy of colorectal cancer liver metastases

Background

Liver metastasis is one of the most common causes of death in patients with colorectal cancer. Therefore, improving the treatment effect of liver metastatic carcinoma of colorectal cancer is also one of the effective ways to improve the survival time of patients with colorectal cancer. The main treatment method for liver metastasis of colorectal cancer is preoperative neoadjuvant chemotherapy through intravenous administration. However, no one has reported a conversion therapy approach for the treatment of colorectal cancer liver metastases patients through arterial infusion chemotherapy combined with targeted agents and PD-1 monoclonal antibody. This case reports a conversion therapy method of liver metastases of colorectal cancer by hepatic arterial infusion chemotherapy (HAIC), sintilimab injection combined with lenvatinib to achieve radical resection of liver metastatic carcinoma after treatment.

Case presentation

The patient was a 69-year-old man who had previously undergone laparoscopic left hemicolectomy for descending colorectal cancer and multiple interventional and surgical treatments for hepatocellular carcinoma. During this treatment, the patient underwent radiological and serological tests, and primary liver cancer was considered at the initial diagnosis stage. Therefore, this liver malignant tumor lesion was treated according to the primary liver cancer treatment protocol before surgical resection. Therefore, the patient received HAIC combined with sintilimab injection and lenvatinib. After three treatment cycles, radiological examination showed no obvious tumor activity, alpha-fetoprotein (AFP) decreased to normal, protein induced by vitamin K absence or antagonist II (PIVKA II) decreased significantly, and the curative effect was evaluated as complete remission. Subsequently, we performed surgical resection of this liver lesion. The pathological response of left lobe tumor was partial remission (PR). Most of the tumors were necrotic and the necrosis rate was greater than 95%. A small amount of live tumor tissue remains (<5%). The pathological classification of this tumor was confirmed as moderately differentiated adenocarcinoma by immunohistochemical staining of multiple tumor indicators in the pathology department. No significant adverse drug events were observed in this patient during treatment.

Conclusion

Hepatic arterial infusion chemotherapy combined with sintilimab injection and lenvatinib conversion therapy provides the opportunity for radical surgical resection of colorectal cancer liver metastases.

Identification of a novel ferroptosis-related gene signature associated with retinal degeneration induced by light damage in mice

Background

Neurodegenerative retinal diseases such as retinitis pigmentosa are serious disorders that may cause irreversible visual impairment. Ferroptosis is a novel type of programmed cell death, and the involvement of ferroptosis in retinal degeneration is still unclear. This study aimed to investigate the related ferroptosis genes in a mice model of retinal degeneration induced by light damage.

Methods

A public dataset of GSE10528 deriving from the Gene Expression Omnibus database was analyzed to identify the differentially expressed genes (DEGs). Gene set enrichment analysis between light damage and control group was conducted. The differentially expressed ferroptosis-related genes (DE-FRGs) were subsequently identified by intersecting the DEGs with a ferroptosis genes dataset retrieved from the FerrDb database. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were further performed using the DE-FRGs. A protein-protein interaction (PPI) network was constructed to identify hub ferroptosis-related genes (HFRGs). The microRNAs (miRNAs)-HFRGs, transcription factors (TFs)-HFRGs networks as well as target drugs potentially interacting with HFRGs were analyzed utilizing bioinformatics algorithms.

Results

A total of 932 DEGs were identified between the light damage and control group. Among these, 25 genes were associated with ferroptosis. GO and KEGG analyses revealed that these DE-FRGs were mainly enriched in apoptotic signaling pathway, response to oxidative stress and autophagy, ferroptosis, necroptosis and cytosolic DNA-sensing pathway. Through PPI network analysis, six hub ferroptosis-related genes (Jun, Stat3, Hmox1, Atf3, Hspa5 and Ripk1) were ultimately identified. All of them were upregulated in light damage retinas, as verified by the GSE146176 dataset. Bioinformatics analyses predicated that 116 miRNAs, 23 TFs and several potential therapeutic compounds might interact with the identified HFRGs.

Conclusion

Our study may provide novel potential biomarkers, therapeutic targets and new insights into the ferroptosis landscape in retinal neurodegenerative diseases.

Rapid adaptive and acute stimulatory responses to low salinity stress in Pacific white shrimp (Litopenaeus vannamei): Insights from integrative transcriptomic and proteomic analysis

The Pacific white shrimp (Litopenaeus vannamei) is a euryhaline crustacean capable of tolerating a wide range of ambient salinity, but the strategies of hepatopancreas to rapid adaptive or acute stimulatory responses to extremely low salinity fluctuations remains unclear. In this study, we integrated transcriptomic and proteomic analyses on the hepatopancreas derived from rapid adaptative (RA) and acute stimulatory (AS) responses to extremely low salinity stress (0.3 ppt) to unveil specific regulatory mechanisms. The RA group displayed normal epithelial cells and tubule structures, while the AS group showed histological changes and lesions. A total of 754 and 649 differentially expressed genes (DEGs) were identified in RA and AS treatments, respectively. For proteome, a total of 206 and 66 differentially expressed proteins (DEPs) were obtained in the RA/CT and AS/CT comparison groups, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were conducted among the DEGs and DEPs, revealing that metabolic related pathways were significantly enriched pathways in both comparison groups. In addition, correlation analysis of transcriptomic and proteomic results showed that 20 and 3 pairs of DEGs/DEPs were identified in RA vs. CT and AS vs. CT comparison groups, respectively. This study is the first report on the rapid adaptive and acute stimulatory transcriptomic and proteomic responses of L. vannamei to extremely low salinity, shedding light on the mechanisms underlying osmoregulation in euryhaline crustaceans.

Hmox1 is Identified as a Ferroptosis Hub Gene and Associated with the M1 Type Microglia/Macrophage Polarization in Spinal Cord Injury: Bioinformatics and Experimental Validation

Ferroptosis and immune cell infiltration are important pathological events in spinal cord injury (SCI), but links between ferroptosis and immune microenvironment after SCI were rare reported. In our study, 77 FRDEGs were screened at 7 days after SCI. GO analysis of FRDEGs showed that aging (GO:0007568; P-value = 1.11E-05) was the most remarkable enriched for biological process, protein binding (GO:0005515; adjusted P-value = 4.44E-06) was the most significantly enriched for molecular function, cytosol (GO:0005829; adjusted P-value = 1.51E-04) was the most prominent enriched for cellular component. Meanwhile, Ferroptosis was significantly enriched both in KEGG (rno04216; adjusted P-value = 0.001) and GSEA (NES = 1.35; adjusted P-value = 0.004) analysis. Next, Hmox1 (Log2Fold change = 6.52; adjusted P-value = 0.004) was identified as one of hub genes in SCI-induced ferroptosis. In the results of immune cell infiltration analysis, proportion of microglia/macrophage was significantly increased after SCI, and Hmox1 was found to positively correlate to the M1 type microglia/macrophage abundance. Finally, effects of Hmox1 on ferroptosis and M1 type polarization were validated in vivo and in vitro. Summarily, we found that Hmox1 was the hub gene in SCI-induced ferroptosis and associated with the M1 type polarization.

Effect of Anisotropic Structural Depth on Orientation and Differentiation Behavior of Skeletal Muscle Cells

Extensive research has been conducted to examine how substrate topological factors are involved in modulating the cell behavior. Among numerous topological factors, the vital influence of the touchable depth of substrates on cell behaviors has already been extensively characterized, but the response of cells to the topological structure at untouchable depth is still elusive. Herein, the influences of substrate depth on myoblast behaviors are systematically investigated using substrates with depths ranging from touchable depth (microgrooved) to untouchable depth (microbridges). The results show that an increase in microgroove depth is accompanied by an inhibited cell spreading, an enhanced elongation, and a more obvious orientation along microgrooves. Interestingly, myoblasts located on microbridges show a more pronounced elongation with increasing culture time but a position-dependent orientation. Myoblasts on the center and parallel boundary of microbridges orient along the bridges, while myoblasts on the vertical boundary align perpendicular to the microbridges. Moreover, the differentiation results of the myoblasts indicate that the differentiated myotubes can maintain this position-dependent orientation. The simulation of the stress field in cell monolayers suggests that the position-dependent orientation is caused by the comprehensive response of myoblasts to the substrate discontinuity and substrate depth. These findings provide valuable insights into the mechanism of cell depth sensing and could inform the design of tissue engineering scaffolds for skeletal muscle and biohybrid actuation.

Characterisation of a Novel Tigecycline Resistance Gene tet(X22) and its Coexistence with blaNDM-1 in a Pseudomonas caeni Isolate

OBJECTIVES

The emergence of pathogens that are resistant to both tigecycline and carbapenem poses a threat to public health globally. Continuous emergence of novel tet(X) variants accelerates the tigecycline resistance crisis. This study aimed to characterise the novel tigecycline resistance gene tet(X22) and its coexistence with carbapenem resistance gene blaNDM-1 in Pseudomonas caeni.

METHODS

This P. caeni isolate co-harbouring tet(X22) and blaNDM-1 was systematically investigated using antimicrobial susceptibility testing, conjugation assays, genome sequencing, bioinformatic analyses, cloning of tet(X22) and functional analysis, and protein structure prediction.

RESULTS

The carbapenem-resistant and tigecycline-resistant P. caeni isolate CE14 was obtained from chicken faeces in 2022. CE14 carried multiple antibiotic resistance genes, including the novel tet(X22) and blaNDM-1. Tet(X22) exhibited 64.72-90.48% amino acid identity with other variants [Tet(X) to Tet(X21)]. Cloning of the gene tet(X22) and protein structure prediction revealed that Tet(X22) confers resistance to tetracyclines, including tigecycline. tet(X22) and blaNDM-1 were located in two multidrug-resistant regions of the chromosome.

CONCLUSIONS

The occurrence of the novel ISCR2-flanked tet(X22) in P. caeni suggests that the tet(X) variant has adapted to new hosts and may widely spread to further expand the host range. The future global spread of such pathogens co-harbouring tet(X) and blaNDM variants needs to be continuously monitored according to the One Health approach.

Integrative conjugative elements mediate the high prevalence of tmexCD3-toprJ1b in Proteus spp. of animal source

IMPORTANCE

The emergence and spread of tmexCD-toprJ have greatly weakened the function of tigecycline. Although studies have demonstrated the significance of Proteus as carriers for tmexCD-toprJ, the epidemic mechanism and characteristics of tmexCD-toprJ in Proteus remain unclear. Herein, we deciphered that the umuC gene in VRIII of SXT/R391 ICEs was a hotspot for the integration of tmexCD3-toprJ1b-bearing mobile genetic elements by genomic analysis. The mobilization and dissemination of tmexCD3-toprJ1b in Proteus were mediated by highly prevalent ICEs. Furthermore, the co-occurrence of tmexCD3-toprJ1b-bearing ICEs with other chromosomally encoded multidrug resistance gene islands warned that the chromosomes of Proteus are significant reservoirs of ARGs. Overall, our results provide significant insights for the prevention and control of tmexCD3-toprJ1b in Proteus.

Outer dynein arm docking complex subunit 2 polymorphism rs7893462 modulates hepatocellular carcinoma susceptibility and can serve as an overall survival biomarker for hepatitis B virus-related hepatocellular carcinoma after hepatectomy: a cohort study with a long-term follow-up

BACKGROUND

Genetic variants of outer dynein arm docking complex subunit 2 (ODAD2) have been reported to be closely associated with primary ciliary dyskinesia and colorectal cancer in previous studies, but the association of genetic variants of ODAD2 with hepatocellular carcinoma (HCC) has not been reported.

METHODS

We enrolled 80 healthy subjects and 468 Guangxi hepatitis B virus (HBV)-related HCC patients in this study. A case-control study method was used to explore the association of different ODAD2-rs7893462 genotypes with hepatocarcinogenesis. A comprehensive survival analysis was used to explore the association of rs7893462 with the prognosis of HBV-related HCC in Guangxi.

RESULTS

Through a case-control study, we observed that patients carrying the G allele of rs7893462 had a markedly increased susceptibility to hepatocarcinogenesis (odds ratio = 1.712, 95% confidence interval = 1.032-2.839, P = 0.037). We found that there were significant prognosis differences among three different genotypes of rs7893462. Nomogram analysis suggested that the contribution of rs7893462 polymorphisms to the prognosis of HBV-related HCC was second only to the BCLC stage. Stratified survival analysis suggested that the AG genotype of rs7893462 was an independent prognostic risk factor for HBV-related HCC. Joint effect survival analysis also observed that the AG genotype of rs7893462 combined with clinical parameters could significantly identify HBV-related HCC patients with different prognostic outcomes more accurately, and the AG genotype was also observed to be independent of clinical factors in HBV-related HCC survival.

CONCLUSION

The ODAD2-rs7893462 polymorphisms can be used as an independent prognostic indicator of HBV-related HCC overall survival and are significantly associated with susceptibility to hepatocarcinogenesis.

Genomic insights into linezolid-resistant Enterococci revealed its evolutionary diversity and poxtA copy number heterogeneity

OBJECTIVES

This study aimed to determine the molecular mechanisms of linezolid-resistant enterococci (LRE) in swine slaughterhouses in China and apply the "One Health" perspective to analyse the evolutionary dynamics of poxtA-positive E. faecium in clinical and non-clinical settings worldwide.

METHODS

The phenotypic and genomic characteristics of multiple LRE isolates were systematically investigated using antimicrobial susceptibility testing, transfer assays, evolutionary experiments, quantitative RT-PCR assays, whole-genome sequencing, and bioinformatics analyses.

RESULTS

Swine faeces served as a significant reservoir for LRE isolates, and optrA and poxtA were the primary contributors to linezolid resistance. Co-occurrence network analysis revealed a significant interconnection between optrA and several other ARGs. The poxtA copy number heterogeneity and polymorphism were initially observed in E. faecium parental and evolved isolates. The poxtA-carrying tandem repeat region exhibits high mobility and has undergone extensive duplication owing to linezolid pressure. The poxtA copy number varies from four copies on the plasmid of E. faecium IC25 to 11 copies on the plasmid and six copies on the chromosome in the evolved isolate IC25-50_poxtA. Furthermore, phylogenetic analysis of 185 poxtA-positive E. faecium strains worldwide found that one isolate from a French patient in 2018 shared only two SNPs with CC17 E. faecium isolates IC25 and IC7-2 from this study, highlighting the potential global transmission of CC17 poxtA-positive E. faecium between humans and animals.

CONCLUSION

This study identified amplification of poxtA as a response of E. faecium to linezolid pressure. Phylogenetic analysis shed light on the potential global transmission of hospital-associated CC17 poxtA-positive E. faecium in clinical and non-clinical settings.

Development of a novel combined nomogram integrating deep-learning-assisted CT texture and clinical-radiological features to predict the invasiveness of clinical stage IA part-solid lung adenocarcinoma: a multicentre study

AIM

To develop a novel combined nomogram based on deep-learning-assisted computed tomography (CT) texture (DL-TA) and clinical-radiological features for the preoperative prediction of invasiveness in patients with clinical stage IA lung adenocarcinoma manifesting as part-solid nodules (PSNs).

MATERIALS AND METHODS

This study was conducted from January 2015 to October 2021 at three centres: 355 patients with 355 PSN lung adenocarcinomas who underwent surgical resection were included and classified into the training (n=222) and validation (n=133) cohorts. PSN segmentation on CT images was performed automatically with a commercial deep-learning algorithm, and CT texture features were extracted. The least absolute shrinkage and selection operator was used for feature selection and transformed into a DL-TA score. The combined nomogram that incorporated the DL-TA score and identified clinical-radiological features was developed for the prediction of pathological invasiveness of the PSNs and validated in terms of discrimination and calibration.

RESULTS

The present study generated a combined nomogram for predicting the invasiveness of PSNs that included age, consolidation-to-tumour ratio, smoking status, and DL-TA score, with a C-index of 0.851 (95% confidence interval: 0.826-0.877) for the training cohort and 0.854 (95% confidence interval: 0.817-0.891) for the validation cohort, indicating good discrimination. Furthermore, the model had a Brier score of 0.153 for the training cohort and 0.135 for the validation cohort, indicating good calibration.

CONCLUSION

The developed combined nomogram consisting of the DL-TA score and clinical-radiological features and has the potential to predict the individual risk for the invasiveness of stage IA PSN lung adenocarcinomas.

Macroinvertebrate Response to Internal Nutrient Loading Increases in Shallow Eutrophic Lakes

In eutrophic lakes, even if external loading is controlled, internal nutrient loading delays the recovery of lake eutrophication. When the input of external pollutants is reduced, the dissolved oxygen environment at the sediment interface improves in a season without algal blooms. As an important part of lake ecosystems, macroinvertebrates are sensitive to hypoxia caused by eutrophication; however, how this change affects macroinvertebrates is still unknown. In this study, we analysed the monitoring data of northern Lake Taihu from 2007 to 2019. After 2007, the external loading of Lake Taihu was relatively stable, but eutrophication began to intensify after 2013, and the nutrients in the sediments also began to decline, which was related to the efficient use of nutrients by algal blooms. The community structure and population density of macroinvertebrates showed different responses in different stages. In particular, the density of oligochaetes and the Shannon-Wiener index showed significant differences in their response to different stages, and their sensitivity to eutrophication was significantly reduced. Under eutrophication conditions dominated by internal loading, frequent hypoxia occurs at the sediment interface only when an algal bloom erupts. When there is no bloom, the probability of sediment hypoxia is significantly reduced under the disturbance of wind. Our results indicate that the current method for evaluating lake eutrophication based on oligochaetes and the Shannon-Wiener diversity index may lose its sensitivity.

Emergence of the fourth mobile sulfonamide resistance gene sul4 in clinical Salmonella enterica

The fourth mobile sulfonamide resistance gene sul4 has been discovered in many metagenomic datasets. However, there is no reports of it in cultured bacteria. In this study, a sul4 positive clinical Salmonella enterica SC2020597 was obtained by conventional Salmonella isolation methods and characterized by species identification and antimicrobial susceptibility testing. Meanwhile, the genomic DNA was sequenced using both long-read and short-read methods. Following that, the complete genome was analyzed by bioinformatic methods. The sul4 gene in S. enterica SC2020597 differed from the sul4 identified in metagenomic data by one amino acid and could confer full resistance to sulfamethoxazole. Genetic location analysis showed that the sul4 in SC2020597 was carried by a complex chromosomally integrated hybrid plasmid. ISCR20-like was strongly associated with the mobilization of sul4 by core genetic context analysis. To the best of our knowledge, this is the first report of the emergence of sul4 in clinically cultured S. enterica. More important, the sul4 has the potential to spread to other bacteria with the help of mobile elements.

Positive effects of dietary Clostridium butyricum supplementation on growth performance, antioxidant capacity, immunity and viability against hypoxic stress in largemouth bass

The effects of dietary supplementation of Clostridium butyricum (CB) on growth performance, serum biochemistry, antioxidant activity, mRNA levels of immune-related genes and resistance to hypoxia stress were studied in largemouth bass. Feed with CB0 (control, 0 CFU/kg), CB1 (4.3×108 CFU/kg), CB2 (7.5×108 CFU/kg), CB3 (1.5×109 CFU/kg) and CB4 (3.2×109 CFU/kg) CB for 56 days, and then a 3 h hypoxic stress experiment was performed. The results showed that dietary CB significantly increased the WGR (weight gain rate), SGR (specific growth rate), PDR (protein deposition rate) and ISI (Intestosomatic index) of largemouth bass (P<0.05). Hepatic GH (growth hormone)/IGF-1 (insulin-like growth factor-1) gene expression was significantly upregulated in the CB3 and CB4 groups compared with the CB0 group (P<0.05), while the FC (feed conversion) was significantly decreased (P<0.05). Serum TP (total protein) and GLU (glucose) levels were significantly higher in the CB4 group than in the CB0 group (P<0.05), while the contents of serum AST (aspartate transaminase), ALT (alanine transaminase), AKP (alkline phosphatase) and UN (urea nitrogen) in CB4 were significantly lower than those in CB0 (P<0.05). T-AOC (total antioxidant capacity), SOD (superoxide dismutase), CAT (catalase), POD (peroxidase) and GSH-Px (glutathione peroxidase) activities were significantly higher in CB3 and CB4 groups than in CB0 group (P<0. 05). The liver MDA (malondialdehyde) content of CB1, CB2, CB3 and CB4 groups was significantly higher than that of CB0 group (P<0. 05). The relative expressions of IL-1β (interleukin 1β), TNF-α (tumor necrosis factor α) and TLR22 (toll-like receptor-22) genes in CB2, CB3 and CB4 groups were significantly lower than those in CB0 group (P<0.05). The relative expression of IL-8 (malondialdehyde) and MyD88 (Myeloid differentiation factor 88) genes in the CB4 group was significantly lower than that in the CB0 group (P<0.05). The liver LZM (lysozyme) content of CB2, CB3 and CB4 groups was significantly higher than that of CB0 group (P<0. 05). The relative expression of IL-10 (interleukin 10) and TGF-β (transforming growth factor β) genes in the CB4 group was significantly higher than that in the CB0 group (P<0.05). Under hypoxic stress for 3 h, the CMR of CB0 group was significantly higher than that of CB1, CB2, CB3 and CB4 groups (P<0.05). Dietary CB can improve the growth performance and resistance to hypoxic stress of largemouth bass by regulating the expression of GH/IGF-1 gene and inflammatory factors and inhibiting TLR22/MyD88 signaling pathway.

The characteristics of mcr-bearing plasmids in clinical Salmonella enterica in Sichuan, China, 2014 to 2017

Salmonella is one of the most important zoonotic pathogens and a major cause of foodborne illnesses, posing a serious global public health hazard. The emergence of plasmid-mediated mcr genes in Salmonella has greatly reduced the clinical choice of salmonellosis treatment. The aim of this study was to investigate the plasmid characteristics of mcr-positive Salmonella identified from patients in Sichuan, China during 2014 to 2017 by whole genomes sequencing. In this study, a total of 12 mcr-positive isolates (1.15%, ; mcr-1, n=10; mcr-3, n=2) were identified from 1046 Salmonella isolates using PCR. Further characterization of these isolates was performed through antimicrobial susceptibility testing, conjugation assays, whole genome sequencing, and bioinformatics analysis. The mcr-1 gene in these isolates were carried by three types of typical mcr-1-bearing plasmids widely distributed in Enterobacteriaceae (IncX4, IncI2 and IncHI2). Of note, two mcr-1-harboring IncHI2 plasmids were integrated into chromosomes by insertion sequences. Two mcr-3-bearing plasmids were IncC and IncFIB broad-host-range plasmids respectively. Genetic context analysis found that mcr-1 was mainly located in Tn6330 or truncated Tn6300, and mcr-3 shared a common genetic structure tnpA-mcr-3-dgkA-ISKpn40. Overall, we found that mcr gene in clinical Salmonella were commonly carried by broad-host plasmids and have potential to transfer into other bacteria by these plasmids. Continuous surveillance of MDR Salmonella in humans and investigation the underlying transmission mechanisms of ARGs are vital to curb the current severe AMR concern.

[Reference values for carotid artery intima-media thickness among community adult dwellers in Shenzhen City]

Objective: To establish reference values for carotid intima-media thickness (CIMT) of adult dwellers in Shenzhen City. Methods: The study was conducted based on the Shenzhen heart failure epidemiological survey from 2021 to 2022. In this survey, residents aged 18 years and above in Shenzhen were selected by using a multi-stage stratified random sampling method. General information, cardiovascular disease (CVD) related behavior and carotid ultrasound examination and etc. were collected from the participants. People with CVD factors, a history of atherosclerotic cardiovascular disease, carotid plaque or having no carotid ultrasound examination results were excluded. The parameter regression model based on fractional polynomial was used to establish the reference values of CIMT by age and sex. Results: A total of 2 163 healthy individuals were enrolled in the final analysis, including 576 males (26.6%) and 1 587 females (73.4%). The fractional polynomial regression of the CIMT mean and standard deviation was obtained. For men, the regression was mean_CIMT=0.324 7+0.006 9×age and SD_CIMT=0.076 9+0.001 2×age. For women, the regression was mean_CIMT=0.354 9+0.005 4×age and SD_CIMT=0.041 6+0.002 0×age. Conclusion: The age and sex reference values for CIMT of adult people in Shenzhen established in this study could provide the latest reference standards for early screening of subclinical CVD.

Long-read metagenomic sequencing reveals that high-copy small plasmids shape the highly prevalent antibiotic resistance genes in animal fecal microbiome

The emergence and prevalence of animal-derived antibiotic resistance genes (ARGs) pose a great threat to public health globally. Long-read metagenomic sequencing is increasingly being used to decipher the fate of environmental ARGs. However, the investigations of the distribution, co-occurrence patterns, and host information of animal-derived environmental ARGs with long-read metagenomic sequencing have received little attention. To cover the gap, we employed a novel QitanTech nanopore long-read metagenomic sequencing method to perform a comprehensive and systematic investigation of the microbial communities and antibiotic resistance profiles, as well as to analyze the host information and genetic structures of ARGs in the feces of laying hens. Our results showed that highly abundant and diverse ARGs were detected in the feces of different ages of laying hens, indicating that feeding animal feces was an important reservoir for the enrichment and maintenance of ARGs. The distribution pattern of chromosomal ARGs was more strongly associated with fecal microbial communities than plasmid-mediated ARGs. Further long-read host tracking analysis revealed that ARGs from Proteobacteria are commonly located on plasmids, whereas in Firmicutes, they are usually carried by chromosomes. Co-occurrence analysis displayed that co-selection phenomena of different ARGs were common occurrences and highly active insertion sequences (ISs) could result in the serious prevalence of many ARGs. Notably, small high-copy plasmids played a significant role in the dissemination of several ARGs, such as floR and tet(L), which could disturb the compositions of fecal ARGs. Overall, our findings significantly expand our knowledge of the comprehensive landscape of feeding animal feces resistome, which is important for the prevention and management of multi-drug resistant bacteria in laying hens.

Robot-assisted laparoscopic enucleation in the treatment of leiomyosarcoma of urinary bladder: A case report

Leiomyosarcoma of urinary bladder (LMS-UB) is a highly malignant mesenchymal tumor, accounting for less than 0.5% of all bladder malignancies, with a predominant clinical presentation of hematuria. Here we report a case of low-grade LMS-UB. A 44-year-old male patient was admitted to the hospital with urodynia for 2 weeks. The patient's pelvis CT showed a mass on the right part of the bladder. For this reason, he was initially diagnosed with bladder cancer. We performed a robot-assisted laparoscopic enucleation of the bladder tumor and low-grade LMS-UB was diagnosed with the histopathological examination. He underwent 5 cycles of adjuvant chemotherapy after surgery. At 19months postoperative follow-up, the patient had no symptoms, recurrence, or distant metastasis. There is no report on the treatment of LMS-UB with minimally invasive enucleation worldwide. This case provides a new comprehensive treatment method of enucleation combined with adjuvant chemotherapy for early low-grade LMS-UB to reduce complications and improve patients' quality of life after surgery.

Impact of antibiotics on microbial community in aquatic environment and biodegradation mechanism: a review and bibliometric analysis

Antibiotic residues in aquatic environments pose a potential hazard, and microbes, which play important roles in aquatic ecosystems, are vulnerable to the impacts of antibiotics. This study aimed to analyze the research progress, trends, and hot topics of the impact of antibiotics on microbial community and biodegradation mechanism using bibliometric analysis. An in-depth analysis of the publication characteristics of 6143 articles published between 1990 and 2021 revealed that the number of articles published increased exponentially. The research sites have been mainly concentrated in the Yamuna River, Pearl River, Lake Taihu, Lake Michigan, Danjiangkou Reservoir, etc., illustrating that research around the world is not even. Antibiotics could change the diversity, structure, and ecological functions of bacterial communities, stimulate a widespread abundance of antibiotic-resistant bacteria and antibiotic-resistant genes, and increase the diversity of eukaryotes, thus triggering the shift of food web structure to predatory and pathogenic. Latent Dirichlet allocation theme model analysis showed three clusters, and the research hotspots mainly included the effect of antibiotics on the denitrification process, microplastics combined with antibiotics, and methods for removing antibiotics. Furthermore, the mechanisms of microbe-mediated antibiotic degradation were unraveled, and importantly, we provided bottlenecks and future research perspectives on antibiotics and microbial diversity research.

The emerging nanomedicine-based technology for non-small cell lung cancer immunotherapy: how far are we from an effective treatment

Non-small cell lung cancer (NSCLC) is a prominent etiology of cancer-related mortality. The heterogeneous nature of this disease impedes its accurate diagnosis and efficacious treatment. Consequently, constant advancements in research are imperative in order to comprehend its intricate nature. In addition to currently available therapies, the utilization of nanotechnology presents an opportunity to enhance the clinical outcomes of NSCLC patients. Notably, the burgeoning knowledge of the interaction between the immune system and cancer itself paves the way for developing novel, emerging immunotherapies for treating NSCLC in the early stages of the disease. It is believed that with the novel engineering avenues of nanomedicine, there is a possibility to overcome the inherent limitations derived from conventional and emerging treatments, such as off-site drug cytotoxicity, drug resistance, and administration methods. Combining nanotechnology with the convergence points of current therapies could open up new avenues for meeting the unmet needs of NSCLC treatment.

Key factors driving dissolved organic matter composition and bioavailability in lakes situated along the Eastern Route of the South-to-North Water Diversion Project, China

The Eastern Route of the South-to-North Water Diversion Project (SNWDP-ER) is a large scale multi-decade infrastructure project aiming to divert substantial amounts of water (≈45 billion m³ yr^-1) to alleviate water shortage in comparatively arid regions of northern China. The project has ramifications for hydrological connectivity and biogeochemical cycling of dissolved organic matter (DOM) in regional lakes affected by the project. We carried out an extensive field sampling campaign along the SNWDP-ER in different hydrological seasons of 2018 and monthly observations in Lake Hongze and Lake Luoma from April 2018 to June 2021. We found the lakes connecting to the SNWDP-ER had higher mean DOC, specific UV absorbance, higher ratio of humic-like to protein-like fluorophores (Humic : Protein), and shallower spectral slope (S_275-295) in the wet season compared to the wet-to-dry transition, and dry seasons. The southern lakes and Yangtze River had lower DOC concentration, bioavailable DOC (BDOC), and higher DOM aromaticity compared to the northern two downstream lakes. Ultrahigh-resolution mass spectrometry (FT-ICR MS) revealed higher relative abundance of CHO-containing and aromatic compounds in the Yangtze River and the southern three upstream lakes compared to the northern two lakes. The data from Lake Hongze and Lake Luoma, studied in different hydrological seasons, suggest that water delivery had high consistency in DOM composition and BDOC over the season. We conclude that positioning along the watercourse and seasonally variable hydrological conditions play an important role in influencing the DOM composition and bioavailability of key lakes connecting to the SNWDP-ER. Our results indicated that the water diversion project delivers water with low DOC concentration and higher aromaticity and thus is of higher quality since it has higher DOM removal potential during drinking water treatment.

Regulatory mechanism of DHRS2-modified human umbilical cord mesenchymal stem cells-derived exosomes in prostate cancer cell proliferation and apoptosis

Prostate cancer (PCa) is a prevalent cause of morbidity and mortality. DHRS2-modified human umbilical cord mesenchymal stem cells-derived exosomes (hUC-MSCs-derived exos) function in PCa. We explored the mechanism of DHRS2-modified hUC-MSCs-derived exos in PCa cell malignant behaviors. DHRS2 expression levels in WPMY-1 cells and 4 PCa cell lines were detected by RT-qPCR and Western blot. 22Rv1/DU145 cells with high/low DHRS2 expression were selected to establish the low/high DHRS2 expression models by transfection. Cell proliferation and apoptosis were detected by CCK-8, colony formation assays, and flow cytometry. hUC-MSCs were identified by oil red O, alizarin staining, and flow cytometry. Exos were extracted from hUC-MSCs by ultracentrifugation and identified by transmission electron microscopy, Nano series-Nano-ZS, and Western blot. DU145 cells were selected for in vitro study to further study the effects of DHRS2-modified exos on cell proliferation and apoptosis. The effect of DHRS2-modified exos on cell cycle distribution was detected by flow cytometry. DHRS2 was repressed in PCa cells. DHRS2 overexpression suppressed PCa cell proliferation and promoted apoptosis. Exos were successfully isolated from hUC-MSC. DHRS2-modified hUC-MSCs-derived exos carried DHRS2 into PCa cells and blocked malignant behaviors. Briefly, DHRS2 was repressed in PCa cells. DHRS2-modified hUC-MSCs-derived exos blocked PCa cell proliferation and enhanced apoptosis.

Macroinvertebrate diversity and ecosystem functioning across the eutrophication gradients of the middle and lower reaches of Yangtze River lakes (China)

Biodiversity, which strengthens ecosystem stability, ecosystem function, and ecosystem services, is threatened by anthropogenic perturbation and climate change worldwide. However, despite the study of the role of biodiversity in multiple facets of freshwater ecosystems, the linkages between macroinvertebrates diversity and ecosystem functioning have not yet been well-assessed in eutrophication gradients of lowland river-floodplain systems. In this study, we have examined the relationship between macroinvertebrates diversity (species diversity, functional diversity, phylogenetic diversity) and macroinvertebrates biomass across the three typically featured eutrophication gradients: "MACROPHYTE," "TRANSITION," and "PHYTOPLANKTON," of floodplain lakes in the middle and lower reaches of the Yangtze River (China). Our results suggest that macroinvertebrates diversity in three different lacustrine conditions, biomass, and the relationship between diversity and biomass varied along eutrophication gradients. Functional richness and variance (divergence in taxon community) were the two important macroinvertebrate diversity indices, which accounted for the largest amount of variation in the biomass (63% in PHYTOPLANKTON lakes and 57% in MACROPHYTE lakes, respectively). We also found that the macrophyte coverage is more important than the relative abundance in maintaining the macroinvertebrates diversity and biomass in lowland Yangtze floodplain lake systems, while the relative abundance of macrophyte would change the BEF relationship. Our results demonstrate the functional performance of Yangtze River lakes, which would change with increased nutrient loading and decreased macrophyte coverage and would highlight the significance of the restoration of macrophytes to reduce nutrient loads.

Clinical Significance of Visual Training in Improving Visual Function After Retinal Detachment in Adolescents

Context

Epidemiological data has shown that retinal detachment (RD) can occur at any age but has a poor prognosis in the adolescent population, which can cause huge obstacles to their life and learning. Although medications can achieve some curative effect, they have potential side effects and differences in individual efficacy.

Objective

• The study intended to explore the clinical significance of visual training in improving recovery of postoperative visual function after external reduction of retinal detachment in adolescent patients.

Design

The research team designed a prospective randomized controlled study.

Setting

The study took place at Guiyang First People's Hospital in Guiyang, Guizhou, China.

Participants

Participants were 110 adolescents with retinal detachments who underwent external reduction surgery, each on one eye for 110 eyes in total, and who were patients at the hospital between June 2015 and June 2019.

Intervention

The research team assigned 52 participants to the visual-function training group, the intervention group, and 58 participants to the control group, according to the random-number-table method. Each group participated in training method for six months.

Outcome Measures

To compare the groups, the research team measured visual function using the Visual Function scale (VF), binocular fusion function using the Worth Four Light Test (W4LT), and stereoscopic vision using the Titmus Stereo Test. The team obtained preoperative and postoperative data-at baseline, one day before surgery and postoperatively at one month and 3 months, and postintervention at 6 months.

Results

Both groups had visual impairment after surgery. For visual function, the intervention group's scores after surgery increased gradually and were significantly higher than those of the control group at each follow-up time (P < .05). No significant difference in binocular fusion function existed between the groups at baseline or at one month after surgery (P > .05). At 3 months after surgery and postintervention, the proportions of participants in the intervention group with normal binocular fusion function were 86.54% and 88.46%, respectively, compared to that of the control group, at 68.97% and 70.69%, respectively. The intervention group's recovery was significantly better than that of the control group at 3 months after surgery and postintervention, at P < .028 and P < .022, respectively. No significant difference existed between the groups in stereoscopic vision at baseline, at 9.62% and 12.07%, respectively (P > .05). The proportion of participants in the intervention group with normal, binocular, stereoscopic vision increased gradually, and at one and 3 months after surgery and postintervention was 67.31%, 82.69%, and 88.46%, respectively. The intervention group's recovery was significantly better than that of the control group at one and 3 months after surgery and postintervention, at P < .028, P < .010, and P < .013, respectively.

Conclusions

Visual training can effectively promote the recovery of visual function after external reduction of RD in adolescents and improve patients' prognoses. Moreover, long-term persistence can achieve significant effects, making the training worthy of clinical promotion.

PUS1 May Be a Potential Prognostic Biomarker and Therapeutic Target for Hepatocellular Carcinoma

Objective

The mechanisms of pseudouridine synthase (PUS) are not definite in hepatocellular carcinoma (HCC), the objective of this study is to investigate the effect of PUS genes in HCC.

Materials and Methods

Differentially expressed and prognostic gene of PUS enzymes was identified based on The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Gene Expression Profiling Interactive Analysis (GEPIA) databases. For the identified gene, pseudouridine synthase 1 (PUS1), was used for further research. The clinicopathological feature of PUS1 was analyzed by Student's t-test. Prognostic significance was explored by Kaplan-Meier (KM) analysis and Cox proportional hazards regression model. Receiver operating characteristic (ROC) curve was applied to appraise diagnostic and prognostic value. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) and Gene Set Enrichment Analysis (GSEA) were implemented to explore mechanism of PUS1. A Guangxi cohort was applied to verify differential expression. In vitro cell experiments were implemented to investigate the influence for proliferation, reactive oxygen species (ROS) level, migration, and invasion of HCC cells after a knockdown of PUS1.

Results

PUS1 was significantly overexpressed in HCC tissues, and patients with high PUS1 were related to unpromising clinicopathological features. Survival analysis revealed high PUS1 expression was associated with a poor overall survival (OS) and 1 year-recurrence free survival (RFS), was an independent risk factor. Meanwhile, ROC curve showed that PUS1 had a diagnostic and prognostic significance to HCC. Functional enrichment analysis implied that PUS1 may be involved in metabolic pathways, mitochondrial function, non-alcoholic fatty liver disease (NAFLD), and some important carcinogenic pathways. Cell assays revealed that knockdown of PUS1 significantly constrained the migration, proliferation, invasion and improved the ROS level of HCC cells.

Conclusion

PUS1 may be a prognostic biomarker and a underlying treatment target for HCC.

Less Configuration and More Dimensionality: Preparative Heart-Cut Multidimensional Liquid Chromatography Based on Trapping Arrays

The resolving power of multiple dimensional liquid chromatography (mD-LC) is multiplicative as it adds dimensions. However, the issue in creating a preparative mD-LC system is that the higher the dimensionality, the more complicated the system configuration. Thus, we presented a new configuration of preparative mD-LC using one set of LC modules and trapping array-based multiple heart-cut interfaces. A preparative two-dimensional liquid chromatography (2D-LC) separation of herbal medicine formulation produced 40 compounds with a purity of >90%. During the separation process, the interface stores the fractions and allocates positions for the fractions from a different dimension; LC draws the fraction from the interface, makes ⁿD separation, and sends isolated fractions to the interface. By repeating this process, we achieved variable dimensionality of LC separations. We also presented a preparative 3D-LC separation of herbal medicines to validate the principle of "less configuration and more dimensionality". Thus, we can explore the higher dimensional preparative separations. The developed preparative mD-LC displayed exceptional power in the isolation of various compounds and has great potential in the application of natural products.

Characteristics and Statistical Analysis of Large and above Hazardous Chemical Accidents in China from 2000 to 2020

To investigate the occurrence and development pattern of large-scale hazardous chemicals emergencies, a statistical analysis of 195 large and above accidents of hazardous chemicals in China during 2000-2020 was conducted. A general description of the characteristics of larger and above accidents based on statistical data was analyzed, and then the system risk of the hazardous chemical industry was calculated and evaluated by the entropy weight method and the TOPSIS method comprehensively. Results show that: (1) The geographical distribution of large and above hazardous chemical accidents (LAHCA) varies significantly; (2) The high-temperature season has high probabilities of having large and above accidents; (3) Human factors and management factors are the main causes of LAHCA; (4) During the period from 2000 to 2020, due to the rapid development of the chemical industry, the overall risk of accidents involving hazardous chemicals were upswing accompanied by volatility, and the risk of serious accidents remains high. The development history of safety regulations in China's hazardous chemical sector and the industry's projected course for future growth were then discussed. Finally, based on the findings of the aforementioned statistics and research, specific recommendations were provided for the safety management of the hazardous chemical sector. This study expects to provide a practical and effective reference for the construction of safety management as well as accident prevention in the hazardous chemical industry.

The ribosomal chaperone NACA recruits PHD2 to cotranslationally modify HIF-α

Prolyl hydroxylase domain protein 2 (PHD2)-catalyzed modification of hypoxia-inducible factor (HIF)-α is a key event in oxygen sensing. We previously showed that the zinc finger of PHD2 binds to a Pro-Xaa-Leu-Glu (PXLE) motif. Here, we show that the zinc finger binds to this motif in the ribosomal chaperone nascent polypeptide complex-α (NACA). This recruits PHD2 to the translation machinery to cotranslationally modify HIF-α. Importantly, this cotranslational modification is enhanced by a translational pause sequence in HIF-α. Mice with a knock-in Naca gene mutation that abolishes the PXLE motif display erythrocytosis, a reflection of HIF pathway dysregulation. In addition, human erythrocytosis-associated mutations in the zinc finger of PHD2 ablate interaction with NACA. Tibetans, who have adapted to the hypoxia of high altitude, harbor a PHD2 variant that we previously showed displays a defect in zinc finger binding to p23, a PXLE-containing HSP90 cochaperone. We show here that Tibetan PHD2 maintains interaction with NACA, thereby showing differential interactions with PXLE-containing proteins and providing an explanation for why Tibetans are not predisposed to erythrocytosis.

Research on the optimization strategy of lithium battery electrode correction system based on algorithm fusion

In the control system of a lithium battery rolling mill, the correction system was crucial. This was because the correction system had a significant impact on the performance of the lithium battery rolling mill, including high precision and efficient rolling quality. However, the non-linearity of the correction system and the uncertainty of the correction system made it a challenging problem to achieve a high precision correction control. The contribution and innovation of this paper was a genetic fuzzy PID control strategy based on Kalman filter, which was proposed and applied to the control of lithium battery rolling mill correction technology. In order to achieve intelligent control of a high-precision electrode rolling mill correction system, an algorithm fusion control scheme was proposed. Firstly, a novel and detailed correction system model was presented. Next, the initial PID parameters of the correction were optimized by means of a genetic algorithm so that the PID parameters could be adapted to the correction control process and then optimized again by adding an extended Kalman filter. Finally, the lithium battery rolling mill correction control system was validated, tested and commissioned in the field. The results showed that the designed algorithm could meet the working requirements of the lithium battery rolling mill and that it improved the accuracy of the correction system. In the actual lithium battery rolling mill production process, the algorithm was compared with a conventional PID. Compared with the common single algorithm, the fusion algorithm proposed in this paper was a complete set of high precision correction control system algorithm to solve the high precision problem faced by the correction system in the actual lithium battery rolling mill correction system.

Experimental Study on Seismic Performance of Precast Columns Repaired with CFRP Fabrics

Earthquakes worldwide highlight the seismic vulnerability of reinforced concrete (RC) bridge columns. RC bridges are likely to collapse or lose service function due to damage to the bridge columns from strong earthquakes. Rapid repair of RC bridge columns is of great significance for maintaining traffic lines for emergency rescue work after earthquakes. In this study, an improved rapid repair method was developed to restore the bearing capacity of a damaged precast column after earthquake damage. A cyclic loading test was performed to simulate the seismic loading. The original column and the repaired column were both tested. The test results showed that the bearing capacity of the repaired columns was increased by 8%, and the energy dissipation capacity was 53% higher than that of the original column. The ductility decreased because the test for the repaired specimen ended in advance. The initial stiffness of the repaired columns was reduced, but the stiffness was significantly developed in the later loading stage. The rapid repair method proposed in this study exhibited an excellent effect on restoring the seismic resistance of the damaged columns.

Persistence of plasmid and tet(X4) in an Escherichia coli isolate coharboring blaNDM-5 and mcr-1 after acquiring an IncFII tet(X4)-positive plasmid

The prevalence of plasmid-mediated tigecycline resistance gene tet(X4) is presenting an increasing trend. Once tet(X4)-bearing plasmids are captured by multidrug-resistant bacteria, such as bla_NDM and mcr-coharboring bacteria, it will promote bacteria to develop an ultra-broad resistance spectrum, limiting clinical treatment options. However, little is known about the destiny of such bacteria or how they will evolve in the future. Herein, we constructed a multidrug-resistant bacteria coharboring tet(X4), bla_NDM-5, and mcr-1 by introducing a tet(X4)-bearing plasmid into a bla_NDM-5 and mcr-1 positive E. coli strain. Subsequently, the stability of tet(X4) and the plasmid was measured after being evolved under tigecycline or antibiotic-free circumstance. Interestingly, we observed both tet(X4)-bearing plasmids in tigecycline treated strains and non-tigecycline treated strains were stable, which might be jointly affected by the increased conjugation frequency and the structural alterations of the tet(X4)-positive plasmid. However, the stability of tet(X4) gene showed different scenarios in the two types of evolved strains. The tet(X4) gene in non-tigecycline treated strains was stable whereas the tet(X4) gene was discarded rapidly in tigecycline treated strains. Accordingly, we found the expression levels of tet(X4) gene in tigecycline-treated strains were several times higher than in non-tigecycline treated strains and ancestral strains, which might in turn impose a stronger burden on the host bacteria. SNPs analysis revealed that a myriad of mutations occurred in genes involving in conjugation transfer, and the missense mutation of marR gene in chromosome of tigecycline treated strains might account for the completely different stability of tet(X4)-bearing plasmid and tet(X4) gene. Collectively, these findings shed a light on the possibility of the emergence of multidrug resistant bacteria due to the transmission of tet(X4)-bearing plasmid, and highlighted that the antibiotic residues may be critical to the development of such bacteria.

Experimental and Numerical Evaluation on the Performance of Perfobond Leiste Shear Connectors in Steel-SFRCC Composite Beams

The difference between the shear performances of Perfobond Leiste (PBL) shear connectors embedded in steel fiber-reinforced cementitious composite (SFRCC) structure and normal strength concrete (NC) structure was investigated by push-out tests and finite element (FE) simulations. Push-out tests were carried out on nine steel-SFRCC specimens and nine steel-NC specimens. The mechanical behavior of the PBL shear connector was examined according to the failure modes, load-slip curves, and strain distribution laws of the push-out specimens. Experimental results revealed that the extension of cracks in SFRCC was hindered by steel fibers, and the number and width of cracks in SFRCC were smaller than those in NC. The failure mode of the steel-SFRCC specimens and the single-hole steel-NC specimens was the shear failure of the penetrating reinforcement, whereas that of the multi-hole NC specimens was concrete slab cracking. The ultimate shear bearing capacity of PBL shear connectors in the steel-SFRCC specimens was 47.8% greater than that in the steel-NC specimens. Furthermore, an FE model verified by the test results was established to conduct parametric analyses. It was found that the hole diameter and thickness of the steel plate and the yield strength of the penetrating rebar greatly affected the shear bearing capacity of PBL shear connectors. Finally, based on the experimental and FE simulation results, an expression for calculating the ultimate shear bearing capacity of PBL shear connectors in the steel-SFRCC composite structure was developed by considering the bearing effects of concrete dowels, penetrating rebars, and end parts.

Occurrence and Characterization of NDM-1-Producing Shewanella spp. and Acinetobacter portensis Co-Harboring tet(X3) in a Chinese Dairy Farm

Bacteria with carbapenem or tigecycline resistance have been spreading widely among humans, animals and the environment globally, being great threats to public health. However, bacteria co-carrying drug resistance genes of carbapenem and tigecycline in Shewanella and Acinetobacter species remain to be investigated. Here, we detected nine blaNDM-1-carrying Shewanella spp. isolates as well as three A. portensis isolates co-harboring tet(X3) and blaNDM-1 from seventy-two samples collected from a dairy farm in China. To explore their genomic characteristic and transmission mechanism, we utilized various methods, including PCR, antimicrobial susceptibility testing, conjugation experiment, whole-genome sequencing, circular intermediate identification and bioinformatics analysis. Clonal dissemination was found among three A. portensis, of which tet(X3) and blaNDM-1 were located on a novel non-conjugative plasmid pJNE5-X3_NDM-1 (333,311 bp), and the circular intermediate ΔISCR2-tet(X3)-blaNDM-1 was identified. Moreover, there was another copy of tet(X3) on the chromosome of A. portensis. It was verified that blaNDM-1 could be transferred to Escherichia coli C600 from Shewanella spp. by conjugation, and self-transmissible IncA/C2 plasmids mediated the transmission of blaNDM-1 in Shewanella spp. strains. Stringent surveillance was warranted to curb the transmission of such vital resistance genes.