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The brain–gut axis is a bidirectional signal transduction system between the gastrointestinal tract and the central nervous system that integrates neural, endocrine, and immune functions. In recent years, the role of the intestinal flora in regulating neural function and affecting the progression of different neurological diseases has received increasing attention. Akkermansia muciniphila is a mucindegrading bacterium of the intestinal flora present in the intestinal mucus layer that can regulate host immunity, the intestinal barrier and neuroimmune homeostasis. In recent years, a growing body of literature has suggested that Akkermansia muciniphila may play beneficial roles in nerve injury and regeneration by regulating brain–gut axis signalling. This review comprehensively summarizes the latest research results on the role of Akkermansia muciniphila in neurological diseases such as spinal cord injury, multiple sclerosis, Parkinson’s disease, and Alzheimer’s disease. The mechanisms by which Akkermansia muciniphila regulates inflammatory cytokines, neurotransmitters, and shortchain fatty acids are also highlighted. Various Akkermansia muciniphila-based interventions, such as those involving outer membrane proteins, extracellular vesicles, and pasteurized Akkermansia muciniphila, are discussed, and their therapeutic potential in restoring intestinal homeostasis, alleviating neuroinflammation, and supporting neuronal repair is explored. Although promising results from animal models have been reported, significant challenges remain in translating these findings into clinical practice and therapeutic applications. The differences in Akkermansia muciniphila colonization efficiency, host responses, and intervention strategies in different disease states limit the results of these studies. In addition, Akkermansia muciniphila may exhibit different mechanisms of action in acute and chronic neurodegenerative diseases, and thus more targeted mechanistic studies are needed. Despite these limitations, Akkermansia muciniphila represents a novel and potent pathway for the modulation of the brain–gut axis to support neural repair and functional recovery. By enhancing intestinal barrier integrity and regulating neuroimmunity, Akkermansia muciniphila has broad prospects as a microbial candidate for the treatment of central nervous system diseases. Future research should focus on optimizing the administration method and clinical trials to verify its efficacy, ultimately providing new treatment options in the field of neural regeneration and microbial therapy.

Biofilm formation is a major factor in the resistance mechanism of Klebsiella pneumoniae. This study aimed to evaluate the effects of sodium hypochlorite on the biofilm of K. pneumoniae with different drug resistance. We collected 3 different types of K. pneumoniae respectively. The growth trend of biofilms of different drug-resistant K. pneumoniae was quantified by measuring the OD₅₉₀ for 7 consecutive days using crystal violet staining. Scanning confocal fluorescence microscopy was used to observe biofilm morphology. After adding sodium hypochlorite, there were significant differences between the OD₅₉₀ value of the 200, 500, and 1,000 µg/mL groups and the positive control group (all P < .05) on the fifth day. Concentrations of 2,000 and 5,000 µg/mL sodium hypochlorite were added after the biofilm had matured. In the 5,000 µg/mL sodium hypochlorite group, the OD₅₉₀ of K. pneumoniae biofilm in the 3 groups decreased significantly compared with the blank control group (all P < .05). Sodium hypochlorite inhibited and cleared the biofilm of K. pneumoniae with different drug resistance, and the effect was enhanced with the increase of concentration in the range of bacteriostatic and bactericidal concentration.

Well diffusion method was used to evaluate the antibacterial activity of Eucalyptus camaldulensis, while the antifungal effect was assessed by calculating the reduction percent in the radial growth of mycelia. The inhibition zones exerted by E. camaldulensis crude extracts varied significantly (p ≤ 0.01). The capsule crude extract (acetone 30%) highly inhibited the growth of Acinetobacter baumannii (35 mm clear zone). The highest antifungal activity was against Rhizopus stolonifer with a reduction percent in its radial growth reached to 96%. The bacterial MICs ranged from 20 to 0.5 mg/mL against Escherichia coli and Bacillus subtilis respectively. The MIC values for fungi were between 18 mg/mL (Mucor sp.) and 4 mg/mL (R. stolonifer). Both type and concentration of the solvent greatly affected the antimicrobial potentials of E. camaldulensis. The empty capsule and bud of E. camaldulensis are recognized for the first time as potentially natural resources of effective antimicrobial agents.

Purpose: A novel variant of OXA-23, named OXA-423, was identified in an Acinetobacter baumannii clinical isolate. The aim of this study was to analyse the resistance phenotype of OXA-423. Methods: The A. baumannii strain WY-0713 was isolated from an intensive care unit patient. PCR was used to detect the bla_OXA-23-like genes. Amplifying, cloning and sequencing were performed for the complete bla_OXA-23-like. The novel bla_OXA-423 and its ancestor bla_OXA-23 were cloned into the expression vector pET-28b(+), and transformed into E. coli Rosetta (DE3) for antibiotic susceptibility testing. SDS-PAGE, modified Hodge test and CarbaNP test were used for detecting the expression of OXA-423 and OXA-23. Results: PCR screening of A. baumannii WY-0713 was positive for bla_OXA-23-like genes. Sequencing of the PCR product identified a novel bla_OXA-23-like, named bla_OXA-423 which encoding OXA-423. OXA-423 differed from OXA-23 by a crucial amino acid substitution (Val128Ala). The V128A substitution was located at the conserved active-site motifs SAV of OXA-23. Antibiotic susceptibility testing performed using isogenic E. coli showed that the MICs of E. coli Rosetta (pET-OXA-423) for penicillins and carbapenems were lower (reduced MICs 4-fold to 16-fold) than that of E. coli Rosetta (pET-OXA-23). The MICs of cefotaxime, ceftazidime and aztreonam for both transformants remained the same as the acceptor strain. Moreover, OXA-423 was slightly inhibited by sulbactam, clavulanic acid and tazobactam. SDS-PAGE analysis showed that OXA-423 and OXA-23 were conspicuously expressed. Modified Hodge test and CarbaNP test were positive demonstrated both of them were functional. Conclusion: OXA-423, the first report of an amino acid substitution located at conserved active-site motifs of OXA-23, conferred lower MIC values of penicillins and carbapenems as compared with OXA-23, while without affecting the resistance profiles of expanded-spectrum cephalosporins and aztreonam.