Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive 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:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Alzheimer's disease (AD) is a common and highly disabling irreversible degenerative disease of the central nervous system, with characteristics as progressive cognitive impairment, memory loss, and behavioral disturbances. Cognitive impairment in AD, being closely associated with amyloid beta-protein (Aβ) deposition, Tau hyperphosphorylation and neuroinflammation, affects the quality of life of patients. Currently, the exact cause of AD remains unclear, and effective treatment options still lacks. In recent years, stem cell-derived exosomes have garnered widespread attention due to their unique biological properties and crucial role in intercellular communication. These exosomes can carry various bioactive molecules, such as proteins, lipids, and RNA, playing significant roles in central nervous system degenerative diseases. Therefore, this article primarily describes the biogenesis, biological characteristics, and advantages of stem cell-derived exosomes, and summarizes their current applications and future prospects in cognitive impairment in AD, aiming to provide new insights for AD treatment.

Objective:To analyze the impact of lymph node dissection on textbook outcomes (TO) and the prognosis of intrahepatic cholangiocarcinoma (ICC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 376 ICC patients who underwent hepatectomy in 4 medical centers, including Mengchao Hepatobiliary Hospital of Fujian Medical University et al, from December 2011 to December 2017 were collected. There were 242 males and 134 females, aged 57(range, 48-63)years. According to the criteria of TO, patients were classified as two cate-gories, including patients achieving TO and not achieving TO. Measurement data with normal distri-bution were represented as Mean± SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M(range) or M( Q1, Q3), and comparison between groups was conducted using the Mann-Whitney U test. Count data were represented as absolute numbers, and comparison between groups was conducted using the chi-square test, Yates adjusted chi-square test or Fisher exact probability. Comparison of ordinal data was conducted using the non-parameter rank sum test. Univariate and multivariate analyses were conducted using the Logistic regression model. The Kaplan-Meier method was used to draw survival curve. Survival analysis was conducted using the Log-rank test. Results:(1) TO situations. Of the 376 ICC patients who underwent hepatectomy, 199 cases achieved TO, including 40 cases with lymph node dissection and 159 cases without lymph node dissection, 177 cases did not achieve TO, including 76 cases with lymph node dissection and 101 cases without lymph node dissection. (2) Influencing factors for TO after hepatectomy of ICC patients. Results of multivariate analysis showed that lymph node dissection, microvascular invasion, nerve invasion and the volume of intraoperative blood loss >800 mL were independent risk factors for achieving TO after hepatec-tomy of ICC patients ( odds ratio=2.22, 2.95, 3.58, 4.09,95% confidence interval as 1.34-3.69, 1.43-6.07, 1.40-9.17, 1.35-12.43, P<0.05). Of the 116 patients with lymph node dissection, 40 cases achieved TO, 103 cases achieved R 0 resection, 38 cases had postoperative complications, 67 cases had delayed hospital stay. The above indicators were 159, 255, 41, 65 of 260 patients without lymph node dissection. There were significant differences in the above indicators between patients with and without lymph node dissection ( χ2=22.90, 15.16, 13.95, 37.78, P<0.05). (3) Follow-up. All the 376 patients were followed up for 19(range, 1-74)months. Of 199 patients achieving TO, the 1-, 2-and 3-year survival rates of 40 patients with lymph node dissection were 54.0%, 36.6% and 26.1%, respectively, versus 67.7%, 42.7% and 34.4% of 159 patients without lymph node dissection, showing no significant difference between them ( χ2=1.89, P>0.05). Of 177 patients not achieving TO, the 1-, 2-and 3-year survival rates of 76 cases with lymph node dissection were 58.9%, 25.7% and 10.3%, respectively, versus 53.0%, 28.5% and 17.2% of 101 cases without lymph node dissection, showing no significant difference between them ( χ2=0.25, P>0.05). Conclusions:Lymph node dissec-tion, microvascular invasion, nerve invasion and the volume of intraoperative blood loss >800 mL are independent risk factors for achieving TO after hepatectomy of ICC patients. Lymph node dissec-tion may increase the postoperative complication rate, prolong the hospital stay and decrease the rate of achieving TO. However, it does not affect the prognosis of patients.

Objective To establish and validate a Nomogram model for predicting the overall survival(OS)of the patients with intrahepatic cholangiocarcinoma(ICC)based on domestic multicenter data,and screen the beneficiaries of adjuvant chemotherapy based on the prediction model.Methods From December 2011 to December 2017,the data of 278 patients with postoperative pathological diagnosis of ICC from 4 medical centers in our country were collected retrospectively COX regression model was used to screen the independent risk factors of OS and constructed a Nomogram model.This model was used to stratify the risk of OS for all patients and to screen the beneficiaries of adjuvant chemotherapy.Results A total of 278 patients were enrolled,and 23 cases(8.3%)received adjuvant chemotherapy.COX multivariate analysis showed that drinking history,ECOG score,method of hepatectomy,lymph node status,number of tumors,and tumor differentiation were independent risk factors for postoperative OS.The Nomogram model had a C-index of 0.690(95%CI:0.646-0.734)in the training cohort and 0.740(95%CI:0.863-0.617)in the validation cohort.According to risk stratification by Nomogram model,in the high-risk group there was a statistically significant difference in survival between adjuvant chemotherapy and non-adjuvant chemotherapy(P=0.033),whereas in the low-risk group,there was no significant difference in survival(P=0.59).Conclusions Nomogram model based on independent risk factors of OS demonstrated excellent predictive capability for survival and could be used to screen,and identify the patients with ICC who benefit from adjuvant chemotherapy.

Purpose To evaluate the added value of time of flight(TOF)and point spread dispersion(PSF)reconstruction in mediastinal lymph node metastasis of lung cancer in 18F-FDG PET/CT imaging.Materials and Methods Sixty-eight lung cancer patients with mediastinal lymph node metastasis who underwent PET/CT examination in the First People's Hospital of Foshan from March 9,2020 to July 23,2021 were analyzed retrospectively.The different methods,including ordered subsets estimation maximization(OSEM),OSEM+TOF,OSEM+PSF,OSEM+TOF+PSF,were used to reconstruct the images.The resolution of different reconstruction algorithms for mediastinal lymph node metastasis of lung cancer,as well as the differences of signal-to-noise ratio(SNR)and standard uptake value(SUV)were compared,respectively.Results The highest values of SUVmean,SUVmax and SNR were obtained via OSEM+TOF+PSF method,which increased by 21.99%,22.86%and 60.14%,compared with conventional OSEM method(t=28.321,19.11,11.059,all P<0.01).The difference percentage in smaller lesions that diameter≤22 mm was significantly higher than that in larger lesions that diameter>22 mm(24.1%vs.21.1%,25.3%vs.19.3%,70.6%vs.63.3%;Z=-3.658,-4.313,-2.154,all P<0.05),and the difference percentage in low contrast lesions that SNR≤15.31 was significantly higher than that in high contrast lesions that SNR>15.31(23.6%vs.21.4%,25.3%vs.21.1%,85.7%vs.46.0%;Z=-3.519,-2.336,-5.106,all P<0.05).Among the evaluation results of lesion detectability of different reconstruction algorithms,OSEM+TOF+PSF image showed the mediastinal lymph node metastasis most clearly(87.4%of the lesions were clearly existing),which was significantly higher than that of OSEM image(73.1%of lesions were clearly existing)(χ2=11.704,P=0.001),however,the proportion of lesions clearly existing in OSEM+PSF image did not significantly increase compared with OSEM image(73.1%vs.75.8%;χ2=0.361,P=0.548).Conclusion The combination of TOF and PSF can significantly improve the detection ability,SNR and SUV of mediastinal lymph node metastasis of lung cancer,especially in small and low contrast lesions.

Non-bifurcating cervical carotid artery(NBCCA)is a very rare anatomical variation of the cervical carotid artery,which may be related to the abnormal development of internal carotid artery(ICA)and external carotid artery in embryonic period.Neither carotid bulb nor a true carotid bifurcation can be observed on the ultrasound of carotid artery while a"stump-like"change was showed at the expected bifurcation level of carotid artery on DSA.Few cases has been reported in China and abroad so far.This article reported a middle-aged male with a history of hypertension and type 2 diabetes and was admitted to the hospital due to dizziness for one month.The left NBCCA accompanied with severe stenosis of the right ICA was confirmed by cerebral angiography.The patient received the right ICA stent implantation surgery as well as antihypertensive and glucose-control treatment and was discharged as his symptoms improved.Clinical data of this case and related literatures were reviewed,in order to improve clinicians'especially imaging diagnostic physicians'understanding on NBCCA to avoid misdiagnosis and related complications.

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 investigate the role of knockdown of peroxiredoxin-6(PRDX6)in injury and adaptive expression of bile acid transporter in human hepatoellular carcinomas(HepG2)cells induced by rifampicin(RFP).Methods Cells in logarithmic growth phase were uniformly inoculated in six-well plates,and HepG2 cells were transiently transfected with specific PRDX6-siRNA and control-siRNA to construct the knockdown group and control group.After 24 h of induction with 100 μmol/L RFP,Western blot and qRT-PCR were performed to detect the protein and gene expression levels of PRDX6,multidrug resistance protein 1(MDR1),multidrug resist-ance-associated proteins 2,3 and 4(MRP2,MRP3 and MRP4),and Na+/taurine taurocholate cotransporter pro-tein(NTCP).Annexin V-FITC/PI double staining assay was used to detect the apoptosis rate of cells in each group;CCK-8 assay was used to detect the changes of cell proliferation in each group;The relative contents of ala-nine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),indirect bilirubin(IBIL)and total bile acid(TBA)in the supernatant of cell culture medium of each group were detected by kits.Results RFP increased the protein and gene expression levels of MRP2,MRP3,MRP4,MDR1,NTCP and PRDX6 in HepG2 cells(P<0.05),while the protein and gene expression levels of MRP2,MRP3,MRP4,MDR1 and NTCP decreased to different degrees after PRDX6 knockdown(P<0.05).In addition,PRDX6 knockdown re-sulted in increased apoptosis rate of HepG2 cells(P<0.05),decreased cell proliferation ability(P<0.05),and increased levels of cell injury markers(ALT,AST,TBIL,DBIL,TBA)in cell culture supernatants(P<0.05).Conclusion RFP increased the protein and gene expression of bile acid transporter and PRDX6 to increase in HepG2 cells.However,following knockdown of PRDX6 and treatment with RFP,the protein and gene expression levels of the bile acid transporter decreased and cell injury was aggravated,suggesting that PRDX6 played a protec-tive role in RFP-induced adaptive response in HepG2 cells.

Objective:To analyze the characteristics of patients with chronic rhinosinusitis (CRS) in the South China region based on pathological tissue biomarkers for regional comparison.Methods:The study population consisted of CRS in-patients in the First Affiliated Hospital of Sun Yat-sen University from October 2019 to June 2022. Among all the 181 cases, 123 of them were male and 58 were female, with an average age of 40. Retrospectively collected clinical data included demographic information, preoperative symptom scores, preoperative endoscopic images, preoperative paranasal sinus computed tomography scanning images, and inflammatory serological features. In addition, 52 variables of pathological tissue biomarkers including cytokines, chemokines and remodeling factors were collected for analysis. Cluster analysis was performed on the integrated data of training set through centroid-based clustering algorithm, and the inflammatory characteristics, post-operation control status, and airway diseases comorbidity of each endotype were analyzed. R project (version 4.2.2) was used in statistical analysis.Results:Cluster analysis divided 181 patients with CRS into 4 endotypes. Cluster 1 ( n=101, 55.80%) showed a locally low inflammatory status. Cluster 2 ( n=23, 12.71%) showed a mixed type of inflammation with predominantly neutrophilic inflammation and tissue remodeling. Cluster 3 ( n=11, 6.08%) was characterized by type Ⅱ inflammation without tissue remodeling. Cluster 4 ( n=46, 25.41%) was mainly characterized by type Ⅱ inflammation with tissue remodeling, showing higher comorbidity rate of asthma and allergic rhinitis. This cluster presented more severe symptoms, significant olfactory dysfunction, extensive overall inflammation based on objective examination results, a notable increase in total eosinophil count and proportion in peripheral blood, and the highest uncontrolled rate observed one year post-surgery. In comparison to other regions, the endotype classification of CRS in Southern China was characterized by a predominant pattern of locally low inflammatory status, a moderate level of type Ⅱ inflammation with tissue remodeling, and a lesser presence of neutrophilic inflammation. Conclusion:CRS distribution in Southern China is mainly characterized by low inflammatory endotype and type Ⅱ inflammation with tissue remodeling. The latter shows more severe clinical manifestations and higher uncontrol rate after surgery.

Objective:To investigate the mid- and long-term training effect of deliberate practice combined with intensive training in cardiopulmonary resuscitation (CPR) teaching for nurses receiving standardized training.Methods:A total of 160 nurses who received the first year of standardized training in Guangdong Provincial Hospital of Traditional Chinese Medicine from July 2020 to March 2021 were enrolled as subjects, and they were randomly divided into experimental group and control group, with 80 nurses in each group. The nurses in the control group received the mode of single deliberate practice, and those in the experimental group received deliberate practice combined with intensive training at months 0, 3, and 6. Assessment was performed for the two groups before and after training,with objective indicators and subjective evaluation as the assessment criteria. Objective score was determined by the immediate objective feedback provided by the electronic display of Resusci Anne ? QCPR, and subjective score was determined by the same group of examiners based on the evaluation of cardiopulmonary resuscitation performed by trainees,including environment evaluation, judgment of consciousness, judgment of respiration, initiation of emergency treatment system, re-evaluation after resuscitation, and overall evaluation. SPSS 18.0 was used for the independent samples t-test, the non-parametric test, and the chi-squares test. Results:After training, there were significant differences between the experimental group and the control group in the objective indicators of the percentage of correct compression (CC%) [85.500 (77.50, 93.00) vs. 81.00 (71.75, 89.00), Z=-2.49, P=0.013] and the proportion of correct ventilation (V%) [84.00 (75.00, 92.75) vs. 80.00 (64.00, 90.25), Z=-2.15, P=0.031]. Both groups had significant improvements in objective and subjective indicators after training (all P<0.05). Conclusions:Deliberate practice combined with intensive training at an interval of 3 months can effectively improve the mid- and long-term CPR skills of nurses receiving standardized training and is more suitable for high-level muscle memory training.