Nanoparticle delivery systems have good application prospects in the field of precision therapy, but the preparation process of nanomaterial has problems such as short in vivo circulation time, easy recognition, and clearance by the immune system in the body. In recent years, biomimetic nanoparticle delivery systems mediated by natural cell membranes have become a research hotspot to address these issues. The natural membrane biomimetic nanoparticle delivery system cleverly integrates the advantages of natural biofilm "autologous" and "artificial" functional carriers by using endogenous cell membranes to modify the surface of nanocarriers, endowing them with characteristics such as tumor targeting, low immunogenicity, and long blood circulation. Currently, biomimetic nanoparticle delivery systems have been used in the treatment of malignant tumors, cardiovascular diseases, bacterial infections, and other diseases. This paper analyzes the development status and current research hotspots of natural cell membrane camouflaged biomimetic nanoparticle delivery systems mainly reviews the latest research progress of red blood cell membrane camouflaged biomimetic nanoparticle delivery systems in the field of disease treatment in recent years. It focuses on exploring the advantages, future development prospects, and limitations of biomimetic nanoparticle delivery systems based on red blood cell membrane camouflage in improving drug delivery, to provide a reference for the in-depth research and development of this system.

Objective To explore the effects of ropivacaine on cognitive dysfunction and synapses in aged rats after tibial fracture.Methods SD male rats were divided into sham operation group,model group and low,medium,high dose experimental groups.Sham operation group was incised and sutured under local anesthesia,and other four groups underwent open tibial fracture operation.Sham operation group and model group were given sevoflurane anesthesia,low,medium and high dose experimental groups were given 0.5,1.0,2.0 mg·kg-1 ropivacaine on the basis of sevoflurane anesthesia.Open field test and Morris water maze test were performed 7 days after operation;Longa score was evaluated;neurotransmitter levels were detected by kit;and Syn1 in hippocampus of rats was detected by immunohistochemistry.Western blot analysis was used to detected the expression of N-methyl-D-aspartate receptor 2B(NMDAR2B),calmodulin-dependent protein kinase Ⅱ(CaMK Ⅱ)and Syn1.Results The Longa scores of sham operation group,model group and low,medium,high dose experimental groups were 0,(3.50±0.71),(2.80±0.63),(2.20±0.63)and(0.90±0.32)points;the integrated optical density of Syn1 were 0.56±0.09,0.25±0.03,0.34±0.03,0.42±0.03 and 0.50±0.05;the expression of Syn1 protein were 1.08±0.12,0.42±0.05,0.55±0.07,0.72±0.06 and 0.86±0.05;the expression of NMDAR2B protein were 1.28±0.13,0.51±0.07,0.69±0.06,0.84±0.07 and 1.02±0.11;CaMK Ⅱ protein were 0.94±0.08,0.36±0.04,0.50±0.06,0.71±0.06 and 0.86±0.06.There were statistically significant differences between sham operation group and model group(P＜0.05);there were significant differences in the above indexes between model group and low,medium,high dose experimental groups(all P＜0.05).Conclusion Ropivacaine can improve cognitive dysfunction and synapses in aged rats after tibial fracture.

2-(4-Methylthiazol-5-yl) ethyl nitrate hydrochloride (W1302) is a nitro containing derivative of clomethiazole, which is a novel neuroprotective agent with both carbon monoxide (NO) donor and weak γ-aminobutyric acid type A (GABA_A) receptor allosteric regulatory excitatory effect. The current study used a rat model of transient middle cerebral arteryocclusion (tMCAO) brain injury to evaluate the therapeutic effect of W1302 on ischemic stroke and explore its potential mechanisms of action. This experiment has been reviewed and approved by the Laboratory Animal Management and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences (ethical review forms No. 620, 632, 5013). The results showed that gavage administration of 1, 3, and 10 mg·kg^-1 of W1302 can significantly reduce the volume of cerebral infarction in rats with ischemia for 2 h and reperfusion for 24 h, and the therapeutic effect was better than that of 200 mg·kg^-1 of DL-3n-butylphthalide. W1302 significantly increased NO levels in blood and brain tissue. It increased cerebral blood flow and brain adenosine triphosphate (ATP) content after reperfusion, as well as, inhibited the expressions of inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in brain tissue. The time window of W1302 was between 120-180 min after ischemia. These research results demonstrated that W1302 could increase NO release, dilate blood vessels, and increase cerebral blood flow, improve energy supply to brain tissue and increase ATP levels, and inhibit neuro-inflammation, which playing the protective roles in tMCAO stroke model rats. This provides theoretical support for the clinical application of W1302 in the treatment of ischemic stroke.

Objective To investigate the efficacies of proximal femoral nail anti-rotation(PFNA)internal fixation in traction bed supine position and non-traction bed lateral position in the treatment of elderly unstable femoral intertrochanteric fractures.Methods The clinical data of patients with unstable femoral intertrochanteric fractures treated with PFNA internal fixation in our hospital were retrospec-tively analyzed,41 patients received treatment in traction bed supine position were included in the supine position group,and 55 patients treated received treatment in non-traction bed lateral position were included in the lateral position group.The perioperative related indicators,surgical reduction,hip Harris score,and incidence of complications in the two groups were analyzed.Results The operation time and incision length of patients in the lateral position group were shorter than those in the supine position group,and the intraoperative blood loss and fluoroscopy times were less than those in the supine position group,with statistically significant differences(P<0.05).There was no significant difference in the anesthesia mode,blood transfusion or hospital stay of patients between the two groups(P>0.05).There was no significant difference in the incidence of postoperative complications of patients between the two groups(P>0.05).There was no significant difference in neck-shaft angle,tip-apex distance or hip Harris score of patients between the two groups(P>0.05).Conclusion PFNA internal fixation in traction bed supine position and non-traction bed lateral position have the same effect in the treatment of elderly unstable femoral intertrochanteric fractures,while the non-traction bed lateral position for treatment has more advantages in shortening operation time,decreasing intraoperative blood loss,and reducing radiation exposure.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

[Objective] To explore the value of the TyG index for predicting postoperative recurrence in persistent atrial fibrillation (AF) patients combined with on-alcoholic fatty liver disease (NAFLD) undergoing catheter ablation. [Methods] This study was a single-center, retrospective, cohort study. Clinical data of patients who underwent catheter ablation during hospitalization or outpatient visits at The First Affiliated Hospital of Xi’an Jiaotong University from January 2021 to December 2022 were retrospectively collected. The patients were divided into recurrence and non-recurrence groups based on whether AF recurred within 1 year after the procedure. General clinical data and relevant laboratory test results were collected, and the preoperative TyG index was calculated. The risk factors for AF recurrence after catheter ablation in these patients were analyzed using univariate and multivariate COX proportional hazards regression models. The value of the TyG index for predicting AF recurrence was assessed using receiver operating characteristic (ROC) curve analysis. [Results] We recruited 167 patients, among whom 103 were males and 64 were females. The mean follow-up time was 12±1.3 months, with 52 cases of AF recurrence and 115 ones of non-recurrence. Compared with the non-recurrence group, the TyG index was higher in the recurrence group (9.62±0.96 vs. 8.26±0.46, P<0.05). Multivariate COX regression analysis showed that the preoperative TyG index (HR=1.35, 95% CI: 1.10-1.60, P<0.05) and postoperative electrocardiogram P-wave dispersion (HR=1.51, 95% CI: 1.32-1.70, P<0.001) were risk factors for AF recurrence after catheter ablation in persistent AF patients with NAFLD. The ROC curve analysis showed that the area under the curve (AUC) for the TyG index in predicting AF recurrence after catheter ablation in these patients was 0.846 (95% CI: 0.773-0.919, P<0.001). [Conclusion] The TyG index is an effective indicator for predicting atrial fibrillation recurrence after catheter ablation in persistent AF patients combined with NAFLD.

Objective To investigate the correlation between traditional Chinese medicine(TCM)syndrome elements and risk factors in children with IgA vasculitis(IgAV,also known as Henoch-Sch?nlein purpura).Methods The medical records of 131 children with IgAV were retrospectively analyzed.And then the distribution of their TCM syndrome elements was investigated,and the correlation of TCM syndrome elements with the gender,age,clinical symptoms,as well as risk factors such as mosquito bite,pathogen infection,and allergic rhinitis was analyzed.Results(1)Among the 131 children with IgAV,the diseases-location syndrome elements of IgAV involved lung in 97 cases(74.05%),spleen in 61 cases(46.56%),kidney in 54 cases(41.22%),liver in 17 cases(12.98%),and heart in 11 cases(8.40%);the disease-nature syndrome elements of IgAV involved blood stasis in 131 cases(100.00%),wind-damp in 125 cases(95.42%),wind-heat in 90 cases(68.70%),damp-heat in 72 cases(54.96%),blood heat in 49 cases(37.40%),qi deficiency in 19 cases(14.50%),and yin deficiency in three cases(2.29%).(2)There were 69 cases(52.67%)of females and 62 cases(47.33%)of males among the IgAV children,with females outnumbering males.The age group of IgAV children was predominated by five to six years old,and 10 cases(7.63%)were younger than four years old,18 cases(13.74%)were four years old,39 cases(29.77%)were five years old,34 cases(25.95%)were six years old,17 cases(12.98%)were seven years old,and 13 cases(9.92%)were older than seven years old.The disease-nature syndrome elements such as blood stasis,wind-damp,wind-heat,and damp-heat were frequently seen in the age group of five to seven years old,yin deficiency was frequently seen in the age group older than seven years,and blood stasis was seen in all age groups.(3)The results of logistic regression analysis of the correlation between TCM syndrome elements and risk factors in IgAV patients showed that allergic rhinitis was positively correlated with blood stasis[OR=2.236,95%CI(1.049-4.007)],damp-heat[OR=2.183,95%CI(1.554-3.671)]and wind-damp[OR=1.202,95%CI(1.050-2.409)];pathogen infection was positively correlated with blood stasis[OR=3.199,95%CI(1.457-4.101)]and damp-heat[OR=1.119,95%CI(1.072-2.009)];mosquito bite was positively correlated with blood stasis[OR=4.533,95%CI(1.029-9.022)]and damp-heat[OR=2.257,95%CI(1.081-13.207)];the gender was positively correlated with blood stasis[OR=1.352,95%CI(1.271-3.018)]and wind-damp[OR=1.149,95%CI(1.071-3.102)].The differences were all statistically significant(P＜0.05 or P＜0.01).Conclusion IgAV usually involves the lungs and is also related to the five zang organs.Its pathogenesis is characterized by excess in superficiality such as blood stasis and wind-damp-heat in the early stage,and is predominated by deficiency in origin such as qi deficiency and yin deficiency in the later stage.For the children with IgAV,mosquito bite,pathogen infection and allergic rhinitis are more likely to induce blood stasis and wind-damp-heat;TCM syndrome elements such as wind-heat,damp-heat,blood heat,and qi deficiency are frequently seen in the males,while TCM syndrome elements such as blood stasis,wind-damp,and yin deficiency are frequently seen in the females.

Cardiac contractility modulation(CCM),as a new implantable electronic therapy device for treating chronic heart failure with reduced ejection fraction(HFrEF),has rapidly become a hot topic in the cardiovascular field due to its ability to enhance ventricular myocardial contractility,improve patients'symptoms and signs,cardiac function indexes and even long-term prognosis.This article reviews the mechanism and clinical studies of CCM in treating HFrEF,and based on its mechanism and signal transduction algorithm,further analyzes and prospects its efficacy in patients with heart failure with preserved ejection fraction,cardiac resynchronization therapy non-response,and HFrEF with concomitant atrial fibrillation,aiming to promote CCM to meet the needs of more diverse clinical situations in heart failure patients.

Objective:To compare the efficacy and clinical value of high-throughput sequencing(HTS)and Sanger sequencing in detecting ABL kinase domain mutations in patients with chronic myeloid leukemia(CML).Methods:A total of 198 samples of 147 CML patients from July 2017 to March 2021 in Henan Cancer Hospital were collected and underwent high-throughput sequencing and Sanger sequencing to detect the mutations in ABL kinase domain,and the relevant clinical data were collected for comparative analysis.Results:The proportion of total mutations and ≥ 2 mutations detected by high-throughput sequencing were significantly higher than those detected by Sanger sequencing(P=0.01;P=0.046).≥ 2 mutations were detected in 22 cases,of which 5 cases(22.7％)had compound mutations.High-throughput sequencing can detect low level mutations that cannot be detected by Sanger sequencing.In 198 samples,25(12.6％)were low level mutations,33(16.7％)were high level mutations and 10(5.1％)were mixed high and low level mutations.In the analysis of related clinical factors,the total mutation rate and the low level mutation rate in the optimal period,failure period and warning period were gradually increased(total mutation rate,P=0.016;low level mutation rate,P=0.005).The mutation rate of the samples with additional chromosomal abnormalities was also significantly increased(P=0.009).The mutation rate of patients who received first-and second-line treatment was significantly lower than that of patients who received third-or higher-line treatment(P=0.006).Analysis based on variant allele frequency(VAF)of the mutation site was helpful to visually evaluate the clonal evolution status of TKI-resistance CML cells.Conclusion:High-throughput sequencing is more sensitive and accurate than Sanger sequencing in mutation detection,which is helpful to accurately and visually evaluate TKI treatment response and optimize treatment strategy for CML.

Objective:To explore the therapeutic efficacy and prognostic factors of induction therapy for secondary central nervous system lymphoma(SCNSL).Methods:Clinical data of patients diagnosed with SCNSL from 2010 to 2021 at Guangdong Provincial People's Hospital were retrospectively collected.A retrospective cohort study was performed on all and grouped patients to analyze the efficacy and survival.Multivariate logistic regression analysis was used to explore the adverse prognostic factors.Results:Thirty-seven diffuse large B-cell lymphoma patients with secondary central involvement were included in the research.Their 2-year overall survival(OS)rate was 46.01％and median survival time was 18.1 months.The 2-year OS rates of HD-MTX group and TMZ group were 34.3％and 61％,median survival time were 8.7 and 38.3 months,and median progression-free survival time were 8.1 and 47 months,respectively.Multivariate logistic regression analysis showed that age,sex,IPI,Ann Arbor stage were correlated with patient survival time.The median survival time of patients with CD79B,KMT2D,CXCR4.ERBB2,TBL1XR1,BTG2,MYC,MYD88,and PIM1 mutations was 8.2 months,which was lower than the overall level.Conclusion:HD-MTX combined with TMZ as the first-line strategy may improve patient prognosis,and early application of gene sequencing is beneficial for evaluating prognosis.