Objective:To establish the minimum number of negative lymph nodes (nLN) required for patients undergoing gastrectomy.Methods:This was a retrospective cohort study with inclusion criteria as follows: (1) radical gastrectomy; (2) histologically confirmed adenocarcinoma; (3) complete tumor staging information; and (4) known number of lymph nodes harvested. The exclusion criteria were: (1) other concurrent malignant tumors; (2) metastatic or recurrent gastric cancer; (3) initial surgery performed at another hospital; (4) preoperative neoadjuvant therapy; (5) distant metastasis; and (6) incomplete clinical data or follow-up information. Based on the above criteria, a total of 11 167 patients with gastric adenocarcinoma who underwent radical subtotal gastrectomy (RSG) or radical total gastrectomy (RTG) in the Department of Gastric Surgery, Fudan University Shanghai Cancer Center between January 1, 2000, and December 31, 2022, were included in the study. Among them, there were 7 596 cases in the RSG group and 3 571 cases in the RTG group. Restricted cubic spline (RCS) analysis was used to determine the ideal threshold for nLN for RSG and RTG patients. Survival analysis was conducted using Kaplan-Meier (KM) curves and log-rank tests, and propensity score matching (PSM) was utilized to balance parameters between two groups. Furthermore, subgroup analysis was conducted for RSG patients based on tumor location (upper, middle and lower) to determine the minimum number of nLN in each subgroup.Results:For patients who underwent RSG, the mean number of nLN was 21.9, with a median of 21. RCS analysis showed that more than 21 nLN was associated with better survival. Moreover, both pre- and post-PSM analysis confirmed that patients with nLN ≥21 had better survival benefits compared to those with nLN <21 (overall survival [OS]: P<0.001 before PSM, P=0.013 after PSM; disease-free survival [DFS]: P<0.001 before PSM, P=0.013 after PSM). For patients who underwent RTG, the mean number of nLN was 23.5, with a median of 22. Here RCS analysis indicated that more than 22 nLN was associated with better postoperative survival in RTG patients, and both pre- and post-PSM analysis confirmed that patients with nLN ≥22 had better survival benefits compared to those with nLN<22 (OS: P<0.001 both before and after PSM; DFS: P<0.001 both before and after PSM). Subgroup analysis showed that for RSG patients with tumor located in the upper part, having ≥17 nLN (OS: both P<0.001), and for RSG patients with tumor located in the middle and lower part, having ≥22 nLN (OS: both P<0.001), were associated with better prognoses. Conclusions:For patients who receive RSG, the minimal number of nLN is ideally ≥21 (upper ≥17, middle and lower ≥22). Similarly, for patients who receive RTG, the minimum number of nLN ideally is 22.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective:To understand the consultation for post-exposure prophylaxis(PEP) services and their related factors among college students who were at high risk for HIV infection in Hangzhou,and to provide a reference basis for formulating an intervention model for college students at high risk of HIV infection.Methods:A cross-sectional survey was conducted between November 2022, and March 2023, in 5 different types of schools in Hangzhou. The subjects should meet the inclusion criteria of age between 18 years and 24 years old self-reported having ever had sex in the past. The sample size was estimated at 864. An online survey was conducted among college students by questionnaire star of an online survey platform to collect their demographic information, sexual behavior characteristics, HIV test status, and consultation for PEP services. The HIV infection risk among participants was evaluated according to their sexual behavior. The consultation for PEP services and the related factors of college students who were at high risk for HIV infection were analyzed.Results:A total of 20 973 college students were surveyed, and 2 291 who have ever had sex were recruited in the study. The proportion assessed as being at high risk for HIV infection was 43.47% (996/2 291), and the proportion of consultation for PEP services was 9.24% (92/996). Multivariate logistic regression analysis showed that among college students who were at high risk for HIV infection, the positive related factors of consultation for PEP services included knowing about PEP services (a OR=17.49, 95% CI: 7.98-38.36) ,having HIV tests (a OR=3.92, 95% CI: 2.08-7.42) and access to condoms on campus (a OR=3.38, 95% CI: 2.02-5.65), and the negative related factor was homosexual orientation (a OR=0.24, 95% CI: 0.06-0.91). Conclusions:Among college students who were at high risk for HIV infection, the proportion of consultation for PEP services was at a lower level. It is necessary to strengthen further the health education of PEP services knowledge among college students, improve the PEP services system, and promote the utilization of PEP services to reduce new HIV infections among college students.

Objective:To analyze the utilization of pre-exposure prophylaxis (PrEP) service against HIV and related factors in young men who have sex with men (MSM) in Hangzhou.Methods:A cross-sectional study design was used in this questionnaire survey in young MSM recurited through local MSM social organization in Hangzhou from September 2022 to March 2023. The estimated sample size was 242. The information about the social-demographic characteristics, behavioral characteristics, utilization of the post exposure prophylaxis (PEP) service, awareness and utilization of PrEP service of the young MSM were collected. Logistic regression model was used to analyze the related factors of the PrEP utilization.Results:A total of 273 young MSM aged 16- 24 years were surveyed in the study. A total for 20.1% (55/273) of them had used PrEP service. Multivariate logistic regression analysis showed that the factors related to PrEP service utilization included age 16-20 years (a OR=3.03, 95% CI:1.12-8.20), education level of senior high school or below (a OR=2.83, 95% CI:1.09-7.35), full-time/part-time work (a OR=3.25, 95% CI: 1.26-8.38), homosexual activity in the past 6 months (a OR=6.71, 95% CI:1.84-24.55), inquiring medical staff about PrEP (a OR=4.71, 95% CI:1.99-11.13) and PEP service use (a OR=6.09, 95% CI:2.69-13.81). Conclusions:The utilization rate of PrEP service was low in young MSM in Hangzhou. It is necessary to strengthen the health education about PrEP and improve the undertanding of PrEP and service capability of medical staff to promote the utilization of PrEP service in young MSM.

Poly(lactic-co-glycolide)(PLGA)is a key excipient in long-acting sustained-release preparations,and its degradation properties directly affect the drug release behavior.In this study,PLGA microspheres were prepared by microfluidic techniques,and the morphology changes of the microspheres were observed by scanning electron microscopy(SEM).In alkaline environment,due to the accelerated hydrolysis of ester bonds,the surface of the microspheres was rapidly dissolved and eroded,and the degradation rate was significantly higher than that in acidic environment.High temperature accelerated the degradation of PLGA microspheres.Under neutral and alkaline conditions,the microspheres showed aggregation and adhesion.Under acidic conditions,the microspheres gradually decomposed into irregular fragments.The high ionic strength further promoted the surface corrosion of the microspheres,especially under extreme pH conditions.Simultaneously,PLGA microspheres encapsulating coumarin were prepared to simulate the microsphere formulation.The release rate of coumarin after degradation of the microspheres under different conditions was observed by measuring the absorbance with ultraviolet-visible spectrophotometry.The results were consistent with those of the blank microspheres.This study revealed that the degradation of PLGA microspheres was significantly pH-dependent,temperature sensitive and ion strength responsive.These findings not only helped to understand and optimize the long-term stability and controlled release performance of drug-carrying microspheres,but also provided a theoretical basis for further improvement of PLGA-based drug carrier design.

Objective To investigate the clinical characteristics in an elderly patient with sellar multiple myeloma.Methods Clinical features,laboratory data and radiologic profile of an elderly patient with sellar multiple myeloma were collected.Results The patient was an 85-year-old male.The main clinical manifestations were fatigue,poor appetite and polyuria.Laboratory examinations showed a significant decrease in blood sodium,several anterior pitu-itary hormones and an increase in total protein,mass of pituitary lesion and concentration of prolactin.During etio-logical screening,it was found that the blood immunoglobulin G(IgG)level was significantly increased,the blood M protein was positive and the bone marrow smear showed myeloma cells accompanied by multiple osteolytic lesions in the bones of the whole body.Considering the diagnosis of multiple myeloma,the pituitary lesion was likely to be the extra-medullary involvement.Conclusions The intrasellar plasmacytoma is not common.The disease onset is insidious with clinical features and imaging findings lacking specificity.Therefore,diagnosis relies on biopsy which poses risks for elderly patients and increases diagnostic challenges leading to misdiagnosis.

Objective To explore the role of sevoflurane(SEV)in sepsis-induced acute lung injury(ALI)and observe its impact on the Wnt/β-catenin signaling pathway.Methods Forty C57 mice were randomly divided into 4 groups(n=10 each):Sham,CLP,SEV,and SEV+XAV(β-catenin inhibitor).A sepsis model was established via cecal ligation and puncture.Lung injury was evaluated using HE staining,lung wet/dry weight ratio,and TUNEL staining.Levels of inflammatory factors(TNF-α,IL-1β,IL-6)were detected by ELISA.Oxidative stress indices(SOD,MDA,ROS)were measured by colorimetry and flow cytometry.Hindlimb blood perfusion and oxygenation were assessed with laser speckle flowmetry.Expressions of key Wnt pathway molecules and down-stream target genes(c-Myc,Cyclin D1)were detected by RT-qPCR and Western blot.Co-localization of β-catenin and SP-C(a marker of type Ⅱ alveolar epithelial cells)in lung tissues was determined by immunofluorescence staining.Results Compared with the Sham group,the CLP group exhibited significant increases in sepsis severity,lung pathological damage including alveolar structure destruction,inflammatory infiltration,and apoptosis,elevation in pro-inflammatory cytokine levels,and significant decrease in SOD and increase in MDA and ROS.Additionally,lower limb blood flow and oxygenation levels were significantly reduced,while the expression of β-catenin and its downstream target genes,as well as the co-localization signal and fluorescence intensity of β-catenin with SP-C,were significantly downregulated(all P<0.05).Compared with the CLP group,the SEV group showed significant improvements in all these indicators.However,compared with the SEV group,the SEV+XAV group demon-strated a reversed protective effect,with all indicators approaching the levels observed in the CLP group(all P<0.05).Conclusion Sevoflurane alleviates sepsis-induced ALI by activating Wnt/β-catenin signaling pathway,exerting anti-inflammatory and antioxidant effects,and enhancing the expression and localization of β-catenin in type Ⅱ alveolar epithelial cells.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

Objective:To understand the consultation for post-exposure prophylaxis(PEP) services and their related factors among college students who were at high risk for HIV infection in Hangzhou,and to provide a reference basis for formulating an intervention model for college students at high risk of HIV infection.Methods:A cross-sectional survey was conducted between November 2022, and March 2023, in 5 different types of schools in Hangzhou. The subjects should meet the inclusion criteria of age between 18 years and 24 years old self-reported having ever had sex in the past. The sample size was estimated at 864. An online survey was conducted among college students by questionnaire star of an online survey platform to collect their demographic information, sexual behavior characteristics, HIV test status, and consultation for PEP services. The HIV infection risk among participants was evaluated according to their sexual behavior. The consultation for PEP services and the related factors of college students who were at high risk for HIV infection were analyzed.Results:A total of 20 973 college students were surveyed, and 2 291 who have ever had sex were recruited in the study. The proportion assessed as being at high risk for HIV infection was 43.47% (996/2 291), and the proportion of consultation for PEP services was 9.24% (92/996). Multivariate logistic regression analysis showed that among college students who were at high risk for HIV infection, the positive related factors of consultation for PEP services included knowing about PEP services (a OR=17.49, 95% CI: 7.98-38.36) ,having HIV tests (a OR=3.92, 95% CI: 2.08-7.42) and access to condoms on campus (a OR=3.38, 95% CI: 2.02-5.65), and the negative related factor was homosexual orientation (a OR=0.24, 95% CI: 0.06-0.91). Conclusions:Among college students who were at high risk for HIV infection, the proportion of consultation for PEP services was at a lower level. It is necessary to strengthen further the health education of PEP services knowledge among college students, improve the PEP services system, and promote the utilization of PEP services to reduce new HIV infections among college students.

Objective:To analyze the utilization of pre-exposure prophylaxis (PrEP) service against HIV and related factors in young men who have sex with men (MSM) in Hangzhou.Methods:A cross-sectional study design was used in this questionnaire survey in young MSM recurited through local MSM social organization in Hangzhou from September 2022 to March 2023. The estimated sample size was 242. The information about the social-demographic characteristics, behavioral characteristics, utilization of the post exposure prophylaxis (PEP) service, awareness and utilization of PrEP service of the young MSM were collected. Logistic regression model was used to analyze the related factors of the PrEP utilization.Results:A total of 273 young MSM aged 16- 24 years were surveyed in the study. A total for 20.1% (55/273) of them had used PrEP service. Multivariate logistic regression analysis showed that the factors related to PrEP service utilization included age 16-20 years (a OR=3.03, 95% CI:1.12-8.20), education level of senior high school or below (a OR=2.83, 95% CI:1.09-7.35), full-time/part-time work (a OR=3.25, 95% CI: 1.26-8.38), homosexual activity in the past 6 months (a OR=6.71, 95% CI:1.84-24.55), inquiring medical staff about PrEP (a OR=4.71, 95% CI:1.99-11.13) and PEP service use (a OR=6.09, 95% CI:2.69-13.81). Conclusions:The utilization rate of PrEP service was low in young MSM in Hangzhou. It is necessary to strengthen the health education about PrEP and improve the undertanding of PrEP and service capability of medical staff to promote the utilization of PrEP service in young MSM.