Pancreatic cancer is characterized by nerve invasion and a high mortality rate， and its pathological process depends on the complex interaction network between tumor and the nervous system. Based on the concept of “pancreatic cancer neuroecology”， this article analyzes the mechanism of action of peripheral motor nerve， sensory nerve， and central nerve in tumorigenesis， pain regulation， and cachexia formation and emphasizes the synergistic regulatory role of immune cells， Schwann cells， and extracellular matrix in the microenvironment of perineural invasion. At the same time， this article further elaborates on the metabolic interaction and chemotaxis between neuraxis and tumor， the effect on promoting chemotherapy resistance， and the dynamic relationship between neuroplasticity and tumor adaptability. In clinical practice， this article summarizes the key value of perineural invasion in prognostic evaluation， preoperative evaluation， and the selection of surgical strategy. In addition， this article reviews the basic research advances in the biomarkers and potential targets associated with perineural invasion in pancreatic cancer and points out the limitations of current model and transformation research. In the future， systematically analyzing the nerve-tumor-immune network and targeting its key nodes may provide multi-dimensional strategies and new breakthroughs for the precise intervention of pancreatic cancer， the reversal of drug resistance， and the relief of symptoms.

Renal tumor scoring systems can describe the anatomical characteristics of renal tumors. It is an important standard to evaluate the surgical complexity and to evaluate the surgical complexity and feasibility of partial nephrectomy. Scholars at home and abroad have established various scoring systems based on different anatomical parameters，such as R.E.N.A.L.，PADUA，C-Index，which are used to guide the clinical selection of surgical modalities，and predict perioperative complications and prognosis. In this paper，various scoring systems are grouped into three major categories according to their functions：prediction of surgical complexity，prediction of complications，and prediction of prognosis. The contents，characteristics and clinical application value of various renal tumor scoring systems are introduced in detail to guide urologists，enhance their surgical decision-making ability，and improve the clinical outcomes.

Background::Very low birth weight (VLBW) infants are the key populations in neonatology, wherein morbidity and mortality remain major challenges. The study aimed to analyze the clinical characteristics of VLBW infants.Methods::A retrospective cohort study was conducted in West China Second Hospital between January 2016 and December 2021. Neonates with a birth weight of <1500 g were included. Mortality, care practices, and major morbidities were analyzed, and compared with those of previous 7 years (2009-2015).Results::Of the total 1750 VLBW, 1386 were infants born with birth weight between 1000-1499 g and 364 infants were born with weight below 1000 g; 42.9% (751/1750) required delivery room resuscitation; 53.9% (943/1750) received non-invasive ventilation only; 38.2% (669/1750) received invasive ventilation; 1517 VLBW infants received complete treatment. Among them, 60.1% (912/1517) of neonates had neonatal respiratory distress syndrome (NRDS), 28.7% (436/1517) had bronchopulmonary dysplasia (BPD), 22.0% (334/1517) had apnea, 11.1% (169/1517) had culture-confirmed sepsis, 8.4% (128/1517) had pulmonary hemorrhage, 7.6% (116/1517) had severe intraventricular hemorrhage (IVH)/periventricular leukomalacia (PVL), 5.7% (87/1517) had necrotizing enterocolitis (NEC), and 2.0% (31/1517) had severe retinopathy of prematurity. The total and in-hospital mortality rates were 9.7% (169/1750) and 3.0% (45/1517), respectively. The top three diagnoses of death among those who had received complete treatment were sepsis, NRDS, and NEC. In 2009-2015, 1146 VLBW were enrolled and 895 infants received complete treatment. The proportions of apnea, IVH, and IVH stage ≥3/PVL, were higher in 2009-2015 compared with those in 2016-2021, while the proportions of NRDS and BPD were characterized by significant increases in 2016-2021. The total and in-hospital mortality rates were 16.7% (191/1146) and 5.6% (50/895) respectively in 2009-2015.Conclusion::Among VLBW infants born in 2016-2021, the total and in-hospital mortality rates were lower than those of neonates born in 2009-2015. Incidences of NRDS and BPD increased in 2016-2021, which affected the survival rates and long-term prognosis of VLBW.

Objective To observe the effect of in situ needle fenestration thoracic endovascular aortic repair(TEVAR)for treating aortic dissection(AD)involving aortic arch.Methods Data of 16 patients with AD involving aortic arch who underwent in situ needle fenestration TEVAR for reconstruction of aortic arch branches were retrospectively analyzed,and the number of fenestration,technical success rate and TEVAR related complications were recorded.Regular follow-up was conducted after TEVAR,the repair of dissection and the patency of fenestrated branch blood vessels were evaluated,the endoleak was assessed,and the survival of patients were recorded.Results The main aortic stent was successfully implanted in all 16 cases.Among them,4 received triple fenestration stent implantation in zones Z0,Z1 and Z2,6 received double fenestration stent implantation in zones Z1 and Z2,2 received double fenestration stent implantation in zones Z0 and Z1 and 4 received single fenestration stent implantation in zone Z2.The success rate of brachiocephalic trunk(BCT)fenestration was 83.33%(5/6).Left common carotid artery(LCCA)-right common carotid artery bypass was performed in 1 case without successful fenestration.The success rate of LCCA fenestration was 100%(12/12).The success rate of left subclavian artery(LSA)fenestration was 87.50%(14/16),2 cases with not successful fenestration were treated with axillar-axillary artery artificial vascular bypass.The technical success rate of intervention was 100%(16/16).Type Ⅰa endoleak occurred in 1 case during TEVAR process and improved after embolization with spring coil.One patient died of pericardial tamponade at the end of TEVAR.Fifteen patients were followed up for a median follow-up time of 20 months.During this period,transient ischemic attack and local small dissection at the proximal beginning of the main stent occurred each in 1 case,which improved after no special treatment.Type Ⅰ endoleak occurred in 1 case,type Ⅲ endoleak occurred in 2 cases,all improved after proximal fenestrated membrane stent implantation or spring coil embolization treatment.One case died of coronary heart disease.Conclusion In situ needle fenestration TEVAR was effective and safe for treating AD involving aortic arch.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.