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ABSTRACTThe increasing antibiotic resistance poses a significant global health challenge, threatening our ability to combat infectious diseases. The phenomenon of collateral sensitivity, whereby resistance to one antibiotic is accompanied by increased sensitivity to another, offers potential avenues for novel therapeutic interventions against infections unresponsive to classical treatments. In this study, we elucidate the emergence of tobramycin (TOB)-resistant small colony variants (SCVs) due to mutations in the hemL gene, which render S. Typhimurium more susceptible to nitrofurantoin (NIT). Mechanistic studies demonstrate that the collateral sensitivity in TOB-resistant S. Typhimurium SCVs primarily stems from disruptions in haem biosynthesis. This leads to dysfunction in the electron transport chain (ETC) and redox imbalance, ultimately inducing lethal accumulation of reactive oxygen species (ROS). Additionally, the upregulation of nfsA/B expressions facilitates the conversion of NIT prodrug into its active form, promoting ROS-mediated bacterial killing and contributing to this collateral sensitivity pattern. Importantly, alternative NIT therapy demonstrates a significant reduction of bacterial load by more than 2.24-log10 cfu/g in the murine thigh infection and colitis models. Our findings corroborate the collateral sensitivity of S. Typhimurium to nitrofurans as a consequence of evolving resistance to aminoglycosides. This provides a promising approach for treating infections due to aminoglycoside-resistant strains.

ABSTRACT: Objectives: Aquatic ecosystems serve as a dissemination pathway and a reservoir of both antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). This study aimed to determine the prevalence of colistin-resistant mcr-like genes in Enterobacteriales in aquatic products, which may be contribute to the transfer of ARGs in water environments. Methods: The mcr-1-positive Escherichia coli were recovered from 123 freshwater fish and 34 cultured crocodile cecum samples from 10 farmers’ markets in Guangdong, China. Minimum inhibitory concentration (MIC) was determined using the agar dilution method. Genotyping was performed using pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Conjugation assay was carried out to investigate the transferability of mcr-1. Genomic information was obtained by whole genome sequencing (WGS) and bioinformatic analysis. Results: Forty-four mcr-1 positive isolates showed co-resistance to tetracycline, trimethoprim/sulfamethoxazole, and gentamicin, while they were all sensitive to tigecycline, meropenem, and amikacin. They were typed into sixteen PFGE clusters. ST10 and ST117 were the most popular sequence types, followed by ST1114. S1-PFGE verified the presence of the mcr-1 gene on plasmids in sizes of ∼60 kb (n = 1) and ∼240 kb (n = 3). Whole genome sequencing-based analysis identified mcr-1 integrated in IncHI2 plasmid (n = 3), IncI2 plasmid (n = 2), and bacterial chromosome in two copies (n = 1). In addition to mcr-1, they carried several other antibiotic resistance genes, such as blaCTX-M-14, fosA3, and aac(6’)-Ib-cr. Conclusion: These data suggest that aquatic products are an important antibiotic resistance reservoir and highlight possible risks regarding food safety.

As wireless communication devices gain popularity, concerns about the potential risks of environmental exposure to complex frequency electromagnetic radiation (EMR) on mental health have become a public health issue. Historically, EMR research has predominantly focused on single- frequency electromagnetic waves, neglecting the study of multi-frequency electromagnetic waves, which more accurately represent everyday life. To address these concerns, our study compared the emotional effects of single-frequency and dual-frequency EMR while exploring potential molecular mechanisms and intervention targets. Our results revealed that single-frequency EMR at 2.65 or 0.8 GHz did not induce anxiety-like behavior in mice. However, exposure to dual-frequency EMR at 2.65/0.8 GHz significantly led to anxiety-like behavior in mice. Further analysis of mouse sera revealed substantial increases in corticosterone and corticotrophin releasing hormone levels following exposure to 2.65/0.8 GHz EMR. Transcriptome sequencing indicated a significant decrease in the expression of Cnr1, encoding cannabinoid receptor 1 Type (CB1R), in the cerebral. This finding was consistently verified through western blot analysis, revealing a substantial reduction in CB1R content. Additionally, a significant decrease in the endocannabinoid 2-arachidonoylglycerol was observed in the cerebral cortex. Remarkably, administering the cannabinoid receptor agonist Win55-212-2 significantly alleviated the anxiety-like behavior, and the cannabinoid receptor antagonist AM251 effectively counteracted the anti-anxiety effects of Win55-212-2. In summary, our research confirmed that dual-frequency EMR is more likely to induce anxiety-like behavior in mice than single-frequency EMR, with implications for the hypothalamic–pituitary–adrenal axis and the endocannabinoid system. Furthermore, our findings suggest that Win55-212-2 may represent a novel avenue for researching and developing anti-EMR drugs.

Most VR fire escape training programs only task learners to observe the procedure of fire escape in different simulated fire scenes. To improve the effectiveness of such training programs for everyone, we tested a “fire escape virtual reality training program” which takes advantage of the feedback on the action to help individuals to learn the necessary and correct steps of fire escape. The virtual program emulates a real fire scene by providing realistic visual and auditory stimuli. A single-group quasi-experimental study was carried out to measure the effectiveness of the program, and a total of 173 seventh- and eighth-grade students from a high school in New Taipei City participated. The results of structural equation modeling showed that 1) gameplay self-efficacy was negatively predicted by frustration, 2) fire presence positively predicted gameplay self-efficacy, and 3) gameplay self-efficacy positively predicted learning progress. The findings suggested that critical life-saving skills such as fire escape skills can be readily acquired and trained through individual virtual reality training programs.

ABSTRACT Streptococcus suis is a zoonotic pathogen that causes disease in humans after exposure to infected pigs or pig-derived food products. In this study, we examined the serotype distribution, antimicrobial resistance phenotypes and genotypes, integrative and conjugative elements (ICEs), and associated genomic environments of S. suis isolates from humans and pigs in China from 2008 to 2019. We identified isolates of 13 serotypes, predominated by serotype 2 (40/96; 41.7%), serotype 3 (10/96; 10.4%), and serotype 1 (6/96; 6.3%). Whole-genome sequencing analysis revealed that these isolates possessed 36 different sequence types (STs), and ST242 and ST117 were the most prevalent. Phylogenetic analysis revealed possible animal and human clonal transmission, while antimicrobial susceptibility testing indicated high-level resistance to macrolides, tetracyclines, and aminoglycosides. These isolates carried 24 antibiotic resistance genes (ARGs) that conferred resistance to 7 antibiotic classes. The antibiotic resistance genotypes were directly correlated with the observed phenotypes. We also identified ICEs in 10 isolates, which were present in 4 different genetic environments and possessed differing ARG combinations. We also predicted and confirmed by PCR analysis the existence of a translocatable unit (TU) in which the oxazolidinone resistance gene optrA was flanked by IS1216E elements. One-half (5/10) of the ICE-carrying strains could be mobilized by conjugation. A comparison of the parental recipient with an ICE-carrying transconjugant in a mouse in vivo thigh infection model indicated that the ICE strain could not be eliminated with tetracycline treatment. S. suis therefore poses a significant challenge to global public health and requires continuous monitoring, especially for the presence of ICEs and associated ARGs that can be transferred via conjugation. IMPORTANCE S. suis is a serious zoonotic pathogen. In this study, we investigated the epidemiological and molecular characteristics of 96 S. suis isolates from 10 different provinces of China from 2008 to 2019. A subset of these isolates (10) carried ICEs that were able to be horizontally transferred among isolates of different S. suis serotypes. A mouse thigh infection model revealed that ICE-facilitated ARG transfer promoted resistance development. S. suis requires continuous monitoring, especially for the presence of ICEs and associated ARGs that can be transferred via conjugation.

Abstract Background The compound Danshen Dripping Pill (CDDP), which is a mixture of extracts from Radix Salviae and Panax notoginseng, is a patented traditional Chinese medicine that is widely used in multiple countries for relieving coronary heart disease (CHD), but its pharmacological mechanism has not been fully elucidated. In this study, we screened the key pharmacological pathways and targets of CDDP that act on CHD using a network pharmacology-based strategy, and the angiogenic activity of CDDP was directly visually investigated in zebrafish embryos in vivo. Methods The potential therapeutic targets and pathways were predicted through a bioinformatics analysis. The proangiogenic effects of CDDP were examined using vascular sprouting assays on subintestinal vessels (SIVs) and optic arteries (OAs) as well as injury assays on intersegmental vessels (ISVs). Pharmacological experiments were applied to confirm the pathway involved. Results Sixty-five potential therapeutic targets of CDDP on CHD were identified and enriched in the PI3K/AKT and VEGF/VEGFR pathways. An in vivo study revealed that CDDP promoted angiogenesis in SIVs and OAs in a dose-dependent manner and relieved the impairments in ISVs induced by lenvatinib, a VEGF receptor kinase inhibitor (VRI). In addition, Vegfaa and Kdrl expression were significantly upregulated after CDDP treatment. Furthermore, the proangiogenic effect of CDDP could be abolished by PI3K/AKT pathway inhibitors. Conclusions CDDP has a proangiogenic effect, the mechanism of which involves the VEGF/VEGFR and PI3K/AKT signaling pathways. These results suggest a new insight into the cardiovascular protective effect of CDDP.

This investigation employs first‐principles calculations to explore the interaction between imidazolium ionic liquids (ILs) and fluoride additives on lithium metal surface. Our focus lies in the comprehensive analysis of three distinct categories of fluorinated additives, each differing in their degree of fluorination. The computations reveal that fluorination plays a significant role in determining both the ionic conductivity and the formation of the solid–electrolyte interphase (SEI) film. Specifically, heightened fluorination enhances the oxidative stability of the system but diminishes the strength of solvent binding, resulting in the formation of larger salt/anion clusters and a decrease in ionic conductivity. Conversely, increased fluorination facilitates the interaction between fluorinated additives and the lithium metal surface, thereby aiding in the formation of a stable SEI film characterized by an abundance of inorganic LiF components. This is important as it serves to suppress dendrite growth and mitigate interface side reactions. Considering the combined influences of ionic conductivity and film formation, 1FP is suggested as the optimal candidate for pyridine‐based additive systems, with FEC preferred for cyclic ester‐based additive systems and BC for chain ester‐based additive systems. This study provides theoretical references for the design of ionic liquid‐fluorinated additive electrolyte systems that can protect the lithium metal anode. [ABSTRACT FROM AUTHOR]

This paper investigates the effectiveness of improvisation in creative thinking development in dance education. The study used the experimental method, which implies conducting a survey and identifying the level of creative thinking development. The following methods were used to study the level of creativity: the Reisman Diagnostic Assessment of Creativity method, Assessment of the creative potential of an individual, The Torrance Tests of Creative Thinking (TTCT). The study was conducted at the School of Music and Dance at Hunan First Normal University. A total of 561 students participated in the study. The findings show there is a statistically significant (p <.05) difference between the students' self-assessment of creativity and their level of creativity, instructors' selected expertise, knowledge level, professional competencies and skills as the primary criteria. The results of the pre-test and post-test show that the indicators of the high level increased from 51% to 61%, and the average level from 27% to 34%. Low-level indicators, on the contrary, decreased from 12% to 5%. [ABSTRACT FROM AUTHOR]

Objective: This study focuses on improving the stability and water solubility of astaxanthin. Methods: Phytosterol α-linolenic acid ester was synthesized by chemical method with phytosterol and α-linolenic acid as raw materials. Liposomes co-encapsulating astaxanthin and phytosterol α-linolenic acid ester were prepared by employing a thin-film ultrasound technique with the utilization of soybean phospholipid. Results: Based on the structure analysis by infrared spectroscopy and nuclear magnetic resonance, it has been demonstrated that the product was phytosterol α-linolenic acid ester. The purity of phytosterol α-linolenic acid ester was （90.72±2.09）% by gas chromatography. The encapsulation efficiency of liposomes co-encapsulating astaxanthin and phytosterol α-linolenic acid ester were （95.00±0.66）%, the average particle size was （158.70±9.70） nm, the polydispersity index （PDI） was 0.35±0.02, and the average zeta potential was （-33.87±2.48） mV. Transmission electron microscopy revealed that the complex liposomes were spherical with regular shape and uniform particle size distribution. Conclusion: Phytosterol α-linolenic acid ester could be applied in the preparation of astaxanthin-loaded liposomes.