OBJECTIVE: To investigate the mechanism of autophagy in regulating bacterial translocation in intestinal infection caused by hypervirulent Klebsiella pneumonia (hvKp) and explore the method of reducing translocation infection of intestinal bacteria. METHODS: Fifty C57BL/6J mice were divided into gavage group (n = 40) and control group (CO group, n = 10). The gavage group was orally administered with 200 μL/d of hvKp (colony count of 10⁹ CFU/mL) continuously for 5 days to establish a hvKp intestinal infection model. CO group was given an equal amount of normal saline. After the experiment, the mice were anesthetized with lsofluraneand euthanized with cervical dislocation under anesthesia. Peripheral venous blood of mice was collected to detect bacterial translocation by 16S rDNA sequencing, then divided into translocation group (BT+ group) and non-translocation group (BT- group). Hematoxylin-eosin (HE) staining was used to evaluate intestinal morphology. The ultrastructural changes of intestinal tissues were observed by electron microscope. The levels of intestinal oxidative stress indicators such as superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GPx) were measured. Translocation was detected by in situ hybridization. The expression of tight junction protein microtubule-associated protein 1 light chain 3-II (LC3-II) and autophagy protein Beclin-1 were measured by Western blotting. The mRNA expression of tight junction proteins ZO-1 and Claudin-2 were detected by reverse transcription-polymerase chain reaction (RT-PCR). The expression of autophagy protein and tight junction protein were observed by immunofluorescence. RESULTS: Two out of 40 mice in the gavage group died after developing aspiration pneumonia. All mice in the CO group survived. The 16S rDNA sequencing results showed that no bacteria were detected in the peripheral blood of the CO group, but bacteria were detected in the peripheral blood of 18 mice in the gavage group, with a bacterial translocation rate of 47.4%. The BT- and BT+ groups showed intestinal mucosal tissue damage, with severe damage in the BT+ group. Compared with the CO group, the level of MDA in the BT- and BT+ groups were significantly increased, while the activities of SOD and GPx were significantly decreased. Compared with the BT- group, the MDA level in the BT+ group further increased, while the SOD and GPx activities further decreased [MDA (mmol/mg): 2.98±0.11 vs. 2.48±0.11, SOD (U/mg): 62.40±5.45 vs. 73.40±4.08, GPx (U/mg): 254.72±10.80 vs. 303.55±8.57, all P < 0.01]. The results of in situ hybridization detection showed that after continuous gastric lavage for 5 days, displaced hvKp was detected in the intestinal mucosal lamina propria and liver tissue of the BT+ group. Compared with the CO group, the protein expressions of LC3-II and Beclin-1 in the BT- and BT+ groups were significantly increased. The protein expressions of LC3-II and Beclin-1 in the BT+ group were obviously lower than those in the BT- group (LC3-II/β-actin: 0.38±0.04 vs. 0.70±0.09, Beclin-1/β-actin: 0.62±0.05 vs. 0.86±0.05, both P < 0.01), and there were autophagosomes in the intestinal mucosa. These results indicated that intestinal mucosal autophagy was activated after hvKp continuous gavage. Compared with CO group, the mRNA expressions of ZO-1 and Claudin-2 in the BT- and BT+ groups were significantly decreased. Compared with the BT- group, the mRNA expressions of ZO-1 and Claudin-2 in the BT+ group was further reduced [ZO-1 mRNA (2^-ΔΔCT): 0.78±0.06 vs. 0.88±0.06, Claudin-2 mRNA (2^-ΔΔCT): 0.40±0.04 vs. 0.70±0.06, both P < 0.01]. The immunofluorescence results showed that the fluorescence intensity of LC3-II, Beclin-1, ZO-1, and Claudin-2 in the BT+ group was significantly lower than that in the BT- group. CONCLUSION HvKp can activate intestinal mucosal autophagy and reduce the damage to intestinal mucosal barrier function by down-regulating oxidative stress level, reduce the occurrence of bacterial translocation.
Animals ; Oxidative Stress ; Mice, Inbred C57BL ; Autophagy ; Intestinal Mucosa/microbiology* ; Bacterial Translocation ; Mice ; Klebsiella Infections/microbiology* ; Superoxide Dismutase/metabolism* ; Beclin-1

OBJECTIVE: To compare the efficacy and safety of intravenous colistin sulfate combined with nebulized inhalation versus intravenous monotherapy for pulmonary infections caused by carbapenem-resistant organism (CRO). METHODS: A multicenter retrospective cohort study was conducted. Clinical data were collected from patients admitted to the intensive care unit (ICU) of 10 tertiary class-A hospitals in Henan Province between July 2021 and May 2023, who received colistin sulfate for CRO pulmonary infections. Data included baseline characteristics, inflammatory markers [white blood cell count (WBC), neutrophil count (NEU), procalcitonin (PCT), C-reactive protein (CRP)], renal function indicators [serum creatinine (SCr), blood urea nitrogen (BUN)], life support measures, anti-infection regimens, clinical efficacy, microbiological clearance rate, and prognostic outcomes. Patients were divided into two groups: intravenous group (colistin sulfate monotherapy via intravenous infusion) and combination group ((intravenous infusion combined with nebulized inhalation of colistin sulfate). Changes in parameters before and after treatment were analyzed. RESULTS: A total of 137 patients with CRO pulmonary infections were enrolled, including 89 in the intravenous group and 48 in the combination group. Baseline characteristics, life support measures, daily colistin dose, and combination regimens (most commonly colistin sulfate plus carbapenems in both groups) showed no significant differences between two groups. The combination group exhibited higher clinical efficacy [77.1% (37/48) vs. 59.6% (52/89)] and microbiological clearance rate [60.4% (29/48) vs. 39.3% (35/89)], both P < 0.05. Pre-treatment inflammatory and renal parameters showed no significant differences between two groups. Post-treatment, the combination group showed significantly lower WBC and CRP [WBC (×10⁹/L): 8.2±0.5 vs. 10.9±0.6, CRP (mg/L): 14.0 (5.7, 26.6) vs. 52.1 (24.4, 109.6), both P < 0.05], whereas NEU, PCT, SCr, and BUN levels showed no significant between two groups. ICU length of stay was shorter in the combination group [days: 16 (10, 25) vs. 21 (14, 29), P < 0.05], although mechanical ventilation duration and total hospitalization showed no significant differences between two groups. CONCLUSIONS Intravenous colistin sulfate combined with nebulized inhalation improved clinical efficacy and microbiological clearance in CRO pulmonary infections with an acceptable safety profile.
Humans ; Colistin/therapeutic use* ; Retrospective Studies ; Administration, Inhalation ; Anti-Bacterial Agents/therapeutic use* ; Carbapenems/pharmacology* ; Male ; Female ; Middle Aged ; Gram-Negative Bacteria/drug effects* ; Aged ; Treatment Outcome ; Respiratory Tract Infections/drug therapy*

Given the increasing concern regarding antibacterial resistance, the antimicrobial properties of naphthoquinones have recently attracted significant attention. While 1,4-naphthoquinone and its derivatives have been extensively studied, the antibacterial properties of 5,8-dihydroxy-1,4-naphthoquinone derivatives remain relatively unexplored. This study presents a comprehensive in vitro and in vivo analysis of the antibacterial activity of 35 naturally sourced and chemically synthesized derivatives of 5,8-dihydroxy-1,4-naphthoquinone. Kirby-Bauer antibiotic testing identified three compounds with activity against methicillin-resistant Staphylococcus aureus (MRSA), with one compound (PNP-02) demonstrating activity comparable to vancomycin in minimum inhibitory concentration, minimum bactericidal concentration (MBC), and time-kill assays. Microscopic and biochemical analyses revealed that PNP-02 adversely affects the cell wall and cell membrane of MRSA. Mechanistic investigations, including proteomic sequencing analyses, Western blotting, and RT-qPCR assays, indicated that PNP-02 compromises cell membrane integrity by inhibiting arginine biosynthesis and pyrimidine metabolism pathways, thereby increasing membrane permeability and inducing bacterial death. In an in vivo mouse model of skin wound healing, PNP-02 exhibited antibacterial efficacy similar to vancomycin. The compound demonstrated low toxicity to cultured human cells and in hemolysis assays and remained stable during serum incubation. These findings suggest that PNP-02 possesses promising bioactivity against MRSA and represents a potential novel antibacterial agent.
Methicillin-Resistant Staphylococcus aureus/genetics* ; Anti-Bacterial Agents/chemistry* ; Naphthoquinones/administration & dosage* ; Animals ; Microbial Sensitivity Tests ; Mice ; Humans ; Staphylococcal Infections/microbiology* ; Molecular Structure

Salmonellosis represents a global epidemic, and the emergence of extensively drug-resistant (XDR) Salmonella and its sustained transmission worldwide constitutes a significant public health concern. Flagellum-mediated motility serves as a crucial virulence trait of Salmonella that guides the pathogen toward the epithelial surface, enhancing gut colonization. Artemisia argyit essential oil, a traditional herb extract, demonstrates efficacy in treating inflammation-related symptoms and diseases; however, its effects on flagellum assembly and expression mechanisms in anti-Salmonella activity remain inadequately explored. This study aimed to elucidate the mechanism by which Artemisia argyit essential oil addresses Salmonella infections. Network pharmacological analysis revealed that Traditional Chinese Medicine (TCM) Artemisia argyit exhibited anti-Salmonella infection potential and inhibited flagellum-dependent motility. The application of Artemisia argyit essential oil induced notable motility defects through the downregulation of flagellar and fimbriae expression. Moreover, it significantly reduced Salmonella-infected cell damage by interfering with flagellum-mediated Salmonella colonization. In vivo studies demonstrated that Artemisia argyit essential oil administration effectively alleviated Salmonella infection symptoms by reducing bacterial loads, inhibiting interleukin-1 beta (IL-1β), IL-6, and tumor necrosis factor-alpha (TNF-α) production, and diminishing pathological injury. Gas chromatography-mass spectrometry (GC-MS) analysis identified forty-three compounds in Artemisia argyit essential oil, with their corresponding targets and active ingredients predicted. Investigation of an in vivo model of Salmonella infection using the active ingredient demonstrated that alpha-cedrene ameliorated Salmonella infection. These findings suggest the potential application of Artemisia argyit essential oil in controlling Salmonella, the predominant food-borne pathogen.
Artemisia/chemistry* ; Oils, Volatile/chemistry* ; Animals ; Flagella/drug effects* ; Salmonella Infections/microbiology* ; Humans ; Mice ; Anti-Bacterial Agents/pharmacology* ; Salmonella/pathogenicity*

Helicobacter pylori is a bacterium that can cause chronic gastritis, peptic ulcers, and other gastrointestinal diseases. The World Health Organization has classified H. pylori as a group Ⅰ carcinogen. Antibiotics are the primary clinical approach for eradicating H. pylori. However, incomplete eradication of H. pylori by antibiotics can lead to persistent infection, which is a major risk factor for the high incidence of gastric cancer. The widespread use of antibiotics has led to the emergence of multidrug resistance in H. pylori, contributing to treatment failures of chronic gastric diseases and increasing the risk of spreading resistant strains. Multidrug-resistant H. pylori has become a serious challenge in the diagnosis and treatment of gastrointestinal diseases. This paper reviews the global trends in the development of multidrug resistance in H. pylori, the underlying mechanisms, the challenges it poses to clinical diagnosis, and its impact on drug development, drawing on relevant literature and the research findings from our group. It proposes using cgt expression as a novel method for determining viable bacteria, identifying intracellularization as a new form of resistance in H. pylori, and exploring the potential of O-glycans as a therapeutic approach against H. pylori to address multidrug resistance. It provides new insights into understanding the mechanisms of H. pylori multidrug resistance and its prevention strategies, offering promising directions for future clinical treatments and antimicrobial drug development.
Helicobacter pylori/genetics* ; Humans ; Drug Resistance, Multiple, Bacterial ; Helicobacter Infections/microbiology* ; Anti-Bacterial Agents/therapeutic use* ; Gastrointestinal Diseases/drug therapy*

Acinetobacter baumannii is a Gram-negative opportunistic pathogen widely distributed in hospital settings. It can survive for a long time and cause a variety of infections, including pneumonia, septicemia, urinary tract infections, and meningitis. The bacterium demonstrates extensive resistance, particularly to critical antibiotics like carbapenems and polymyxins, posing a serious threat to the recovery of severely ill patients. Carbapenem-resistant A. baumannii has been designated as a pathogen of critical priority on the World Health Organization (WHO) Bacterial Pathogen Priority List, requiring urgent development of new therapeutic agents. Phages, as a novel biological control approach, exhibit substantial potential in combating A. baumannii infections due to their specific ability to infect and lyse bacteria. This review highlights the application and potential of phages and phage-derived enzymes against multidrug-resistant A. baumannii, considering the epidemiological trends of A. baumannii in China, with the aim of providing innovative insights and strategies for phage therapy of drug-resistant bacterial infections.
Acinetobacter baumannii/drug effects* ; Drug Resistance, Multiple, Bacterial ; Phage Therapy/methods* ; Acinetobacter Infections/microbiology* ; Humans ; Bacteriophages/physiology* ; Anti-Bacterial Agents/pharmacology*

BACKGROUND: Owing to the high prevalence of antibiotic resistance in Helicobacter pylori ( H. pylori ) in China, bismuth-containing quadruple therapies have been recommended for H. pylori eradication. This study compared the efficacy and safety of quadruple regimens containing vonoprazan vs . esomeprazole for H. pylori eradication in a patient population in China. METHODS: This was a phase 3, multicenter, randomized, double-blind study. Patients with confirmed H. pylori infection were randomized 1:1 to receive quadruple therapy for 14 days: amoxicillin 1000 mg and clarithromycin 500 mg after meals, bismuth potassium citrate 600 mg before meals, plus either vonoprazan 20 mg or esomeprazole 20 mg before meals, all twice daily. The primary outcome was the eradication rate of H. pylori , evaluated using a 13 C urea breath test at 4 weeks after treatment. The non-inferiority margin was at 10%. RESULTS: The study included 510 patients, 506 of whom completed the follow-up assessment. The primary analysis revealed eradication rates of 86.8% (210/242) and 86.7% (208/240) for vonoprazan and esomeprazole therapy, respectively (treatment difference: 0.1%; 95% confidence interval [CI]: -5.95, 6.17; non-inferiority P  = 0.0009). Per-protocol analysis showed eradication rates of 87.4% for vonoprazan and 86.3% for esomeprazole (treatment difference: 1.2%; 95% CI: -5.03, 7.36; non-inferiority P  = 0.0004). Vonoprazan and esomeprazole were well tolerated, with similar safety profiles. CONCLUSION: Vonoprazan was found to be well-tolerated and non-inferior to esomeprazole for eradicating H. pylori in patients from China. TRIAL REGISTRATION ClinicalTrials.gov , NCT04198363.
Humans ; Esomeprazole/therapeutic use* ; Double-Blind Method ; Helicobacter Infections/drug therapy* ; Male ; Female ; Middle Aged ; Helicobacter pylori/pathogenicity* ; Pyrroles/therapeutic use* ; Sulfonamides/therapeutic use* ; Adult ; Clarithromycin/therapeutic use* ; Amoxicillin/therapeutic use* ; Aged ; Anti-Bacterial Agents/therapeutic use* ; Pyrrolidines/therapeutic use* ; Drug Therapy, Combination ; Proton Pump Inhibitors/therapeutic use*

BACKGROUND: The effect of the interval between previous Helicobacter pylori (H. pylori) eradication and rescue treatment on therapeutic outcomes remains unknown. The aim of this study was to investigate the association between eradication rates and treatment interval durations in H. pylori infections. METHODS: This prospective observational study was conducted from December 2021 to February 2023 at six tertiary hospitals in Shandong, China. We recruited patients who were positive for H. pylori infection and required rescue treatment. Demographic information, previous times of eradication therapy, last eradication therapy date, and history of antibiotic use data were collected. The patients were divided into four groups based on the rescue treatment interval length: Group A, ≥4 weeks and ≤3 months; Group B, >3 and ≤6 months; Group C, >6 and ≤12 months; and Group D, >12 months. The primary outcome was the eradication rate of H. pylori . Drug compliance and adverse events (AEs) were also assessed. Pearson's χ2 test or Fisher's exact test was used to compare eradication rates between groups. RESULTS: A total of 670 patients were enrolled in this study. The intention-to-treat (ITT) eradication rates were 88.3% (158/179) in Group A, 89.6% (120/134) in Group B, 89.1% (123/138) in Group C, and 87.7% (192/219) in Group D. The per-protocol (PP) eradication rates were 92.9% (156/168) in Group A, 94.5% (120/127) in Group B, 94.5% (121/128) in Group C, and 93.6% (190/203) in Group D. There was no statistically significant difference in the eradication rates between groups in either the ITT ( P = 0.949) or PP analysis ( P = 0.921). No significant differences were observed in the incidence of AEs ( P = 0.934) or drug compliance ( P = 0.849) between groups. CONCLUSION: The interval duration of rescue treatment had no significant effect on H. pylori eradication rates or the incidence of AEs. REGISTRATION ClinicalTrials.gov , NCT05173493.
Humans ; Helicobacter Infections/drug therapy* ; Helicobacter pylori/pathogenicity* ; Male ; Female ; Prospective Studies ; Middle Aged ; Anti-Bacterial Agents/adverse effects* ; Adult ; Aged ; Treatment Outcome ; Proton Pump Inhibitors/therapeutic use*

Antibiotic-resistant (AR) bacterial wound infections (WIs) impose major burdens on healthcare systems, exacerbated by ineffective therapies and stalled antibiotic development. Phage therapy and phage-derived enzymes have gained traction as potent alternatives, leveraging targeted bactericidal mechanisms to combat AR pathogens. In this review, we summarised the antimicrobial mechanisms of both phage therapy and phage-derived enzymes as antimicrobial therapy, and outlined recent advances in their use for in vitro , in vivo and clinical applications for WI management. In addition, we also highlights recent advancements in their development, driven by genetic engineering, chemical modifications, and artificial intelligence. Finally, we identified the potential barriers and challenges they may encounter in clinical practice and the corresponding strategies to address these issues. The entire review gives us a comprehensive understanding of the latest advances in phages and their derivative enzyme therapies for treating WIs, in the hope that research in this field will continue to improve and innovate, accelerating the transition from the laboratory to application at the bedside and ultimately improving the efficacy of treatment for AR bacterial WIs.
Humans ; Phage Therapy/methods* ; Wound Infection/drug therapy* ; Bacteriophages/enzymology* ; Enzyme Therapy/methods* ; Animals ; Bacterial Infections/therapy*

Child ; Humans ; Anti-Bacterial Agents/therapeutic use* ; Community-Acquired Infections/microbiology* ; Meningitis, Bacterial/therapy*