Multidrug-resistant (MDR) bacterial infections have emerged as a serious challenge of global public health crisis. The overuse and misuse of conventional antibiotics have dramatically accelerated the emergence, evolution and worldwide spread of drug-resistant bacterial strains, necessitating urgent exploration of novel antibacterial strategies. Bacteriophages serve as natural bacterial predators offering distinct advantages including high host specificity, autonomous self-replication capabilities and cost-effective large-scale production. However, wild-type phages present significant clinical limitations due to their narrow host ranges, susceptibility to rapid immune clearance and poor penetration of bacterial biofilms, which severely restrict their therapeutic applications. The convergence of synthetic biology, nanotechnology and advanced gene editing technologies has accelerated the development of engineered bacteriophage platforms, providing programmable, scalable and clinically translatable pathways to overcome these inherent biological constraints. Here, we systematically delineate four fundamental strategies for engineered bacteriophage development. Chemical modification utilizes reactive functional groups such as amino, carboxyl and thiol moieties on capsid proteins through esterification, amidation or click chemistry reactions to achieve precise drug conjugation and surface functionalization. In vivo editing encompasses ultraviolet or chemical mutagenesis for random mutation induction, homologous recombination for targeted genetic alterations, recombineering methodologies including electroporation-mediated bacteriophage recombination engineering, and CRISPR-Cas systems for precise genome editing to enable exact genetic reconstruction and host range reprogramming. In vitro synthesis leverages genome engineering platforms where intact phage genomes are transferred into yeast or host bacteria to facilitate highly efficient homologous recombination, enabling large DNA fragment assembly and cross-gene host range expansion without bacterial toxicity constraints. Directed evolution combines artificial selection through mutation library screening with rational design approaches involving chimeric receptor binding protein construction or site-specific mutagenesis, effectively balancing the discovery of unknown adaptive pathways with targeted host specificity modification. Moreover, we comprehensively discuss therapeutic applications across diverse clinical scenarios. Engineered bacteriophage effectively disrupt bacterial biofilms through sophisticated functionalized delivery platforms including nanozyme-conjugated phages, phage-liposome nanoconjugates and bio-responsive hydrogels, demonstrating significantly enhanced bactericidal efficiency compared to unmodified free phages. These bioengineered vectors attenuate bacterial virulence and resensitize pathogens to antibiotics by delivering CRISPR-Cas systems or base editors to disrupt critical virulence factors such as pili, capsule synthesis machineries and quorum sensing systems, or by inactivating antibiotic resistance determinants including beta-lactamase genes. As an intelligent nanomedicine delivery platform, engineered bacteriophage enable precise pathogen elimination an through photocatalytic reactive oxygen species generation, immunomodulatory interventions, or controlled release of antibacterial drugs. Furthermore, oral administration of engineered bacteriophage facilitates microbiota modulation, which selectively eliminate intestinal pathogens while preserve beneficial commensal microbiota, thereby restoring microbial community balance and preventing complications associated with dysbiosis. Finally, we critically analyze persistent challenges including host strain matching complexity, evolution of bacterial resistance mechanisms, pharmacokinetic optimization requirements, optimal administration route selection, large-scale production quality control standards and clinical dosing determination protocols. Through multidisciplinary integration of synthetic biology, infectious disease medicine and immunology, future translational medicine studies of bacteriophage should establish comprehensive technical platforms encompassing rapid phage screening, intelligent rational design, rigorous in vivo evaluation and standardized clinical validation processes, ultimately advancing engineered bacteriophage from laboratory innovations to clinically approved therapeutics for effectively combating MDR bacterial infections.

Cryopreservation is the primary technique for in vitro preservation of allogeneic tissue. However, its success is often hindered by factors such as low temperature, ischemia, and hypoxia. This study investigated the potential of Sini Decoction, known for its antioxidant and anti-apoptotic properties, to reduce cryopreservation-induced injury in rats' sciatic nerves. Sini Decoction was prepared according to the Chinese Pharmacopoeia, and its cytotoxicity on Rsc96 cells was assessed by using the CCK-8 method. Sini Decoction at concentrations of 4, 8, and 16 mg·mL~(-1), termed as low-(SL), medium-(SM), and high-(SH) doses group, was used for cryopreservation of rats' sciatic nerves. A normal control(NC) group and a fresh nerve control(fresh) group were set. Flow cytometry and TUNEL staining were used to detect the apoptosis of neural tissue cells after cryopreservation. Western blot was used to detect the expression of apoptosis-related proteins(Bcl-2, Bax, caspase-3, and caspase-8) and nerve regeneration proteins(NGF and BDNF) in vitro after cryopreservation. Oxidative damage of neural tissue after cryopreservation was evaluated by measuring levels of GSH, SOD, MDA, ROS, and ATP. Cryopreserved nerves were then used for allogeneic transplantation. One week after transplantation, CD4~+ and CD8~+ fluorescent double staining assessed inflammatory cell invasion in the transplanted nerve segment, and ELISA evaluated the expression of serum inflammatory factors(IL-1, IFN-γ, and TNF-α) in recipients. Twenty weeks after transplantation, electrophysiology and NF200 neurofilament staining were used to evaluate nerve regeneration. RESULTS:: showed that Sini Decoction at concentrations of below 32 mg·mL~(-1) exhibited no cytotoxicity to Rsc96 cells. During in vitro nerve cryopreservation, Sini Decoction significantly reduced cell apoptosis, ROS, and MDA production compared to the NC group. In the SH group, the protein expression of NGF and BDNF in vitro, as well as ATP, SOD, and GSH production, were significantly increased. In the rejection reaction one week after transplantation, compared to the fresh nerve transplantation group, the SL and SM groups showed reduced CD4~+ and CD8~+ T cell invasion in the transplanted nerve segment and down-regulated IL-1, IFN-γ, and TNF-α expression in recipient serum. Twenty weeks after transplantation, the electrophysiological test results of CMAP, NCV, and NF200 neurofilament protein fluorescent staining in the SM and SH groups were superior to those in the NC and fresh groups. These findings indicate that Sini Decoction offers protective benefits in the cryopreservation of rats' sciatic nerves and holds significant potential for the in vitro preservation of tissue and organs.
Animals ; Apoptosis/drug effects* ; Rats ; Oxidative Stress/drug effects* ; Sciatic Nerve/cytology* ; Cryopreservation ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Rats, Sprague-Dawley ; Protective Agents/pharmacology*

OBJECTIVE: This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study. METHODS: A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants. RESULTS: Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m ²) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m ²) and obesity (≥ 28.0 kg/m ²) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m ² ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses. CONCLUSION This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans ; Body Mass Index ; China/epidemiology* ; Male ; Female ; Middle Aged ; Prospective Studies ; Rural Population/statistics & numerical data* ; Aged ; Follow-Up Studies ; Adult ; Mortality ; Cause of Death ; Obesity/mortality* ; Overweight/mortality*

Objective To investigate the role of Sneathia sanguinegens(S.sanguinegens)in the development of unexplained recurrent spontaneous abortion(URSA).Methods A case-control study was conducted to analyze the vaginal flora characteristics of 65 patients with URSA and 18 healthy controls through 16S rRNA gene sequencing.Toxicity profile of S.sanguinegens on human cervical cancer cells(ME-180),human umbilical vein endothelial cells(HUVEC)and human placental choriocarcinoma cells(JEG-3)was analyzed at the cellular level to assess the mechanism of it in adverse pregnancy outcomes.And S.sanguinegens was used to infect C57BL/6J mice to explore the toxic effect on living organisms.Results The relative abundance of Sneathia was increased in patients with URSA compared with healthy controls.It was positively correlated with the number of miscarriages,and was attributed to S.sanguinegens.We also found that S.sanguinegens damaged ME-180,JEG-3 and HUVEC cells.The degree of cellular damage was related to the level of S.sanguinegens added.Intravenous infection with S.sanguinegens caused inflammatory damage in several organs and extramedullary hematopoiesis in the spleen.Conclusion S.sanguinegens is closely related to URSA and should be emphasized in patients with high vaginal bacterial load.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:To investigate the anti-heart failure mechanism of N-acetylcysteine(NAC)in diabetic cardiomyop-athy independent from coronary artery factors.Methods:A total of 40 diabetic mice after heart failure model construction were randomly divided into two groups,NAC group(n=20,NAC 100mg·kg-1·d-1)and control group(n=20,Saline 100 mg·kg-1·d-1).Echocardiography was performed to detect left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),left ventricular ejection fraction(LVEF),mitral left ventricular early-dias-tolic peak flow velocity/left ventricular late-diastolic peak flow velocity(E/A),isovolumic relaxation time(IVRT)and cardiac output(CO)after 4 weeks.Terminal uridine nick-end labeling(TUNEL)was performed to detect apoptosis in-dex,and Western Blot was performed to detect the expression of extracellular regulated protein kinases(ERK)1/2 after 6 weeks in two groups.Results:Compared to those in control group,mice in NAC group had significant higher LVEF[(40.5±3.4)％vs.(36.9±3.2)％],E/A[(1.5±0.1)vs.(1.4±0.1)]and CO[(10.3±0.6)ml/min vs.(9.9±0.5)ml/min](P＜0.05 or＜0.01);and significant lower LVESV[(23.1±1.3)μl vs.(24.7±1.5)μl],apoptosis index[(31.2±0.5)％vs.(45.1±0.9)％]and the expression of ERK1/2[(2.2±0.2)vs.(3.9±0.1)](P＜0.001 all).Conclusion:NAC exerts anti-heart failure effect by attenuating apoptosis of cardiomyocytes via regulating ERK1/2 pathway.

The angiogenic response is essential for the repair of ischemic brain tissue. Integrin α6 (Itga6) expression has been shown to increase under hypoxic conditions and is expressed exclusively in vascular structures; however, its role in post-ischemic angiogenesis remains poorly understood. In this study, we demonstrate that mice with endothelial cell-specific knockout of Itga6 exhibit reduced neovascularization, reduced pericyte coverage on microvessels, and accelerated breakdown of microvascular integrity in the peri-infarct area. In vitro, endothelial cells with ITGA6 knockdown display reduced proliferation, migration, and tube-formation. Mechanistically, we demonstrated that ITGA6 regulates post-stroke angiogenesis through the PI3K/Akt-eNOS-VEGFA axis. Importantly, the specific overexpression of Itga6 in endothelial cells significantly enhanced neovascularization and enhanced the integrity of microvessels, leading to improved functional recovery. Our results suggest that endothelial cell Itga6 plays a crucial role in key steps of post-stroke angiogenesis, and may represent a promising therapeutic target for promoting recovery after stroke.
Animals ; Nitric Oxide Synthase Type III/metabolism* ; Mice ; Proto-Oncogene Proteins c-akt/metabolism* ; Integrin alpha6/genetics* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Stroke/pathology* ; Vascular Remodeling/physiology* ; Vascular Endothelial Growth Factor A/metabolism* ; Mice, Knockout ; Signal Transduction/physiology* ; Mice, Inbred C57BL ; Male ; Neovascularization, Physiologic/physiology*

Arsenic is a semi-metal,and lipid-soluble arsenic compounds are one of the widespread forms in the environment and food chain,but there is a lack of standards for lipid-soluble arsenic compounds,which is one of the bottlenecks in the current analytical detection and toxicological studies of organic arsenic.In this study,four saturated arsenic-containing hydrocarbons,AsHC 318,AsHC 332,AsHC 346,and AsHC 374(The number is relative molecular mass),were successfully synthesized in three steps by using dimethylarsinic acid,potassium iodide,sodium hydroxide,and four brominated alkanes(1-Bromotetradecane,1-bromopentadecane,1-bromohexadecane,and 1-bromooctadecane)as raw materials.The structures of these four saturated arsenic-containing hydrocarbons were characterized by proton nuclear magnetic resonance(1H NMR)spectroscopy,13C nuclear magnetic resonance(13C NMR)spectroscopy,and high-resolution mass spectrometry(HR-MS).The yields of the method were 8%-10%,and the synthesized compounds could be used in subsequent toxicity evaluation experiments to assess the toxic effects and mechanisms of action of arsenic-containing hydrocarbons.This study provided an effective method for synthesis of arsenic-containing hydrocarbons,enriching the synthesis methods of arsenic-containing hydrocarbons,and provided raw materials for the subsequent toxicological studies of arsenic-containing hydrocarbons.

AIM To investigate the effects of Changpu Yujin Decoction(CPYJD)on striatal mitophagy and PINK1/Parkin signaling pathway in a rat model of Tourette syndrome(TS).METHODS Thirty-six SPF male SD rats were randomly assigned to the control group(n=9)and the TS modeling group(n=27).Rats in the modeling group received daily intraperitoneal injections of 3,3'-iminodipropionitrile(IDPN)(300 mg/kg)for 7 consecutive days to establish the TS model.Post-modeling,successfully induced TS rats were re-randomized into model group(no treatment),tiapride group(47.91 mg/kg)and CPYJD group(77.28 g/kg).All groups received their respective interventions via intragastric administration daily for 28 days.Following drug administration,behavioral scores were assessed in each group.Pathological alterations in the striatum were examined using HE staining,while ultrastructural changes were evaluated by transmission electron microscopy(TEM).Neuronal apoptosis was quantified via TUNEL staining,and ROS levels in striatum were measured by ELISA.Co-localization of PINK1 and LC3B was assessed using immunofluorescence(IF).Finally,mRNA and protein expressions of PINK1,Parkin,Beclin-1,P62 and LC3B(LC3B-Ⅱ/Ⅰ ratio)were analyzed by RT-qPCR and Western blot.RESULTS Compared to the control group,the model group demonstrated significantly increased behavioral scores(P＜0.01),elevated neuronal apoptosis rate and higher ROS levels in the striatum(P＜0.01);severe neuronal and mitochondrial damage in the striatum;significantly reduced mRNA and protein expressions of PINK1,Parkin,Beclin-1 and LC3B(LC3B-Ⅱ/Ⅰ ratio)in the striatum(P＜0.01);markedly upregulated P62 mRNA and protein expressions(P＜0.01).Compared to the model group,both the tiapride and CPYJD intervention groups exhibited significantly reduced behavioral scores(P＜0.01);decreased neuronal apoptosis rate and lower ROS levels(P＜0.01);improved pathological alterations in the striatal neurons and mitochondria;increased mRNA and protein expressions of PINK1,Parkin and Beclin-1 in the striatum(P＜0.05,P＜0.01);and decreased P62 mRNA and protein expressions(P＜0.01).Furthermore,the rats in the CPYJD group specifically showed elevated LC3B mRNA level and LC3B-Ⅱ/Ⅰ protein ratio in striatum(P＜0.05,P＜0.01).CONCLUSION The effect of CPYJD intervention in TS rats may involve activation of mitophagy through regulation of the PINK1/Parkin signaling pathway,improving mitochondrial function,reducing ROS levels,and thereby protecting neurons.