Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective:To assess the impact of urban-rural health insurance integration on the non-agricultural employment of rural labor in China.Methods:Using CHFS data(2011-2019)and a DID model,this study analyzed the impact on non-agricultural employment probability and quality(wage income,job stability)and examined the effect of different integration models.Results:The integration of urban and rural health insurance significantly increases the probability and quality of non-agricultural employment among rural labor.This effect operates through three key mechanisms:easing household liquidity constraints,improving health-related human capital,and expanding job search scope.Moreover,the"unified urban-rural tier"model proves more effective than the"one-system-multi-tiers"model in promoting non-agricultural employment and enhancing job quality.Conclusion:The integration positively contributes to improving rural labor allocation efficiency and mobilizing surplus rural labor capacity.Policy recommendations include accelerating the adoption of the"unified urban-rural tier"model and further refining the urban-rural resident health insurance system.

AIM To study the chemical constituents from the branches and leaves of Michelia yunnanensis Franch.ex Finet & Gagnep.and their anti-inflammatory activities.METHODS The methanol extract was isolated and purified by silica gel,MCI,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.Their anti-inflammatory activities were evaluated by RAW264.7 model.RESULTS Twenty compounds were isolated and identified as dihydrodehydrodiconifenyl alcohol(1),8-hydroxypinoresinol(2),lariciresinol(3),isolariciresinol(4),(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(5),thero-2,3-bis-(4-hydroxy-3-methoxypheyl)-3-methoxy-propanol(6),evofolin B(7),(E)-p-coumaryl alcohol γ-O-methyl ether(8),ω-hydroxypropioguaiacone(9),sinapaldehyde(10),isoscopoletin(11),6-hydroxy-5,7-dimethoxycoumarin(12),2α,3α-dihydroxy-2-methylbutyrolactone(13),6-hydroxy-3(1-hydroxy-1-methylethyl)-6-methyl-2-cyclohexen-1-one(14),benzofuran-2-carboxaldehyde(15),3,4-dihydroxy-5-methoxybenzaldehyde(16),3,5-dimethoxy-4-hydroxybenzaldehyde(17),3,4-dihydroxybenzaldehyde(18),3,4-dihydroxybenzoic methyl ester(19),vanillic acid(20).The inhibition rate of compound 1 on NO was 45.39％±0.32％.CONCLUSION Compounds 1-16,18-20 are first isolated from this plant.Compound 1 has anti-inflammatory activity.

OBJECTIVE To observe the effect of early warning mechanisms based on nosocomial infection surveil-lance system on precise prevention and control of spread of multidrug-resistant organisms(MDROs)infections in intensive care unit of neurosurgery department.METHODS The dynamic monitoring was performed in the ICU of neurosurgery department of a three-A general hospital by using real-time surveillance system of nosocomial infec-tion from Jan.2023 to Dec.2023.The warning information was sent to the doctor' station immediately once the MDROs infections were detected,the detection of drug-resistant bacteria was carried out for the relevant personnel and their surroundings,and the precise prevention and control measures were implemented.The impact on the iso-lation rate of MDROs,isolation rate of MDROs from the relevant personnel and surroundings,incidence of noso-comial MDROs infections and incidence of surgical site infection was observed after the measures were taken.RESULTS The carrying rate of MDROs was decreased from 21.80％to 5.74％among the relevant personnel after the precise prevention and control measures were taken(P＜0.05),which was improved remarkably among the doctors(decreasing from 21.43％to 6.07％),nurses(decreasing from 23.68％to 3.98％),nursing workers(decreasing from 25.15％to 8.65％),and cleaning staff(decreasing from 25.49％to 5.05％)(P＜0.001).The isolation rate of MDROs was decreased from 20.77％to 7.12％among the surroundings(P＜0.05),which was decreased most remarkably among head cushions(decreasing from 32.28％to 12.13％),bed rails(decreasing from 16.70％to 3.27％),ventilator panels(decreasing from 23.00％to 6.95％)and bedside floors(decreasing from 31.99％to 9.96％)(P＜0.001).The incidence of nosocomial MDROs infections declined from 3.84％to 1.71％(P＜0.05),with incidence of incision infections decreasing from 4.00％to 1.45％(P＜0.05),the inci-dence of intracranial infections decreasing from 2.38％to 0.56％(P＜0.05).CONCLUSION The detection of drug-resistant bacteria is carried out immediately and precisely for the patients with MDROs infection,relevant personnel and their surroundings by using the real-time surveillance system of nosocomial infection,which achieve remarkable effect on prevention of transmission of MDROs and reduction of incidence of hospital-associated infec-tions and surgical site infections.

The purpose of this study is to develop a shark single domain antibody(SdAb)targeting a unique B cell epitope in the SARS-CoV-2 spike protein,and explore its role in the immunological detection targeting SARS-CoV-2 spike protein S.A u-nique peptide S9 was artificially synthesized based on the sequence of a unique B cell epitope of SARS-CoV-2 spike protein,then it was conjugated to the carrier protein KLH.It was used as an immunogen for subcutaneous injection into shark back and boosted according to the standard immunization protocol.Blood collected from shark tail vein and peripheral blood lymphocytes(PBL)were isolated.Total RNA was purified from PBL and transcribed to cDNA by reverse transcription.Shark vNAR frag-ments were amplified from cDNA templates and cloned into pComb3XSS vector to obtain phage library.A positive clone named T01 was obtained through screening the phage library by indirect ELISA.Then its gene was cloned into the expression vector pET-28a.The SdAb T01 was then prokaryotically expressed and purified,and its specific recognition of the SARS-CoV-2 spike protein S was indentified by Western-blot(WB),indirect ELISA and IF A.T01 binds well with peptide S9 at EC50 value of 2.050±0.064 nmol/L.The purified SdAb T01 was proven by WB to be able to selectively detect recombinant spike protein sub-unit 1(S1)of SARS-CoV-2,with no cross-reactive to recombinant spike protein subunit 1 of other six human coronavirus.It was showed by ELISA that SdAb T01 can sensitively detect the recombinant N terminal domain(NTD)of SARS-CoV-2 pro-tein.Moreover,it also specifically recognizes the spike protein of SARS-CoV-2 that was transiently expressed in transfected HEK293 cells by IFA.Therefore,a shark single domain antibody targeting a unique B cell epitope in the spike protein of SARS-CoV-2 was successfully developed,and has shown potential immunodiagnostic value by WB,ELISA and IFA.Thus,it provides an effective tool for unique antigen detection of SARS-CoV-2.

The purpose of this study is to develop a shark single domain antibody(SdAb)targeting a unique B cell epitope in the SARS-CoV-2 spike protein,and explore its role in the immunological detection targeting SARS-CoV-2 spike protein S.A u-nique peptide S9 was artificially synthesized based on the sequence of a unique B cell epitope of SARS-CoV-2 spike protein,then it was conjugated to the carrier protein KLH.It was used as an immunogen for subcutaneous injection into shark back and boosted according to the standard immunization protocol.Blood collected from shark tail vein and peripheral blood lymphocytes(PBL)were isolated.Total RNA was purified from PBL and transcribed to cDNA by reverse transcription.Shark vNAR frag-ments were amplified from cDNA templates and cloned into pComb3XSS vector to obtain phage library.A positive clone named T01 was obtained through screening the phage library by indirect ELISA.Then its gene was cloned into the expression vector pET-28a.The SdAb T01 was then prokaryotically expressed and purified,and its specific recognition of the SARS-CoV-2 spike protein S was indentified by Western-blot(WB),indirect ELISA and IF A.T01 binds well with peptide S9 at EC50 value of 2.050±0.064 nmol/L.The purified SdAb T01 was proven by WB to be able to selectively detect recombinant spike protein sub-unit 1(S1)of SARS-CoV-2,with no cross-reactive to recombinant spike protein subunit 1 of other six human coronavirus.It was showed by ELISA that SdAb T01 can sensitively detect the recombinant N terminal domain(NTD)of SARS-CoV-2 pro-tein.Moreover,it also specifically recognizes the spike protein of SARS-CoV-2 that was transiently expressed in transfected HEK293 cells by IFA.Therefore,a shark single domain antibody targeting a unique B cell epitope in the spike protein of SARS-CoV-2 was successfully developed,and has shown potential immunodiagnostic value by WB,ELISA and IFA.Thus,it provides an effective tool for unique antigen detection of SARS-CoV-2.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

ObjectiveTo investigate the effect of astragaloside Ⅳ（AS-Ⅳ） on the proliferation of vascular smooth muscle cells（VSMCs） induced by angiotensin Ⅱ（Ang Ⅱ） based on solute carrier family 7 member 11/glutathione peroxidase 4（SLC7A11/GPX4） pathway. MethodsPrimary rat thoracic aortic VSMCs were cultured by tissue explant method， and the cell types were identified by immunofluorescence. Cell counting kit-8（CCK-8） was used to determine the optimal concentration and time of AS-Ⅳ after Ang Ⅱ stimulation. The experiment was divided into blank group， model group， AS-Ⅳ group（40 μmol·L^-1）， Erastin group（0.5 μmol·L^-1）， Erastin+AS-Ⅳ group（0.5 μmol·L^-1+40 μmol·L^-1）. The blank group was cultured in normal medium， the model group was cultured in medium containing Ang Ⅱ（0.1 μmol·L^-1）， and each administration group was cultured in medium containing Ang Ⅱ（0.1 μmol·L^-1） and the corresponding doses of drug. CCK-8 and plate clone formation assay were used to detect the proliferation of cells in each group， Prussian blue staining was used to detect cell iron deposition， the content of reactive oxygen species（ROS） in cells was detected by fluorescence probe method， the content of malondialdehyde（MDA） was detected by thiobarbituric acid（TBA） method， and the protein levels of SLC7A11 and GPX4 in each group were detected by Western blot. ResultsPrimary rat thoracic aortic VSMCs were successfully cultured by tissue explant method， and immunofluorescence detection showed that positive expression of α-smooth muscle actin（α-SMA） and negative expression of vimentin in the cells， identifying them as VSMCs. The optimal concentration and time of AS-Ⅳ determined by CCK-8 were 40 μmol·L^-1 and 24 h， respectively. Pharmacodynamic studies showed that compared with the blank group， the cell proliferation in the model group increased， the iron deposition in the cells increased， the contents of ROS and MDA increased， and the expression levels of SLC7A11 and GPX4 proteins decreased（P<0.05， P<0.01）. Compared with the model group， the cell proliferation of the AS-Ⅳ group was inhibited， the iron deposition in the cells was decreased， the contents of ROS and MDA were decreased， and the expression levels of SLC7A11 and GPX4 proteins were increased（P<0.05， P<0.01）. While in the Erastin group， the cell proliferation was increased， the iron deposition was increased， ROS and MDA contents were increased， and the expression levels of SLC7A11 and GPX4 proteins were decreased（P<0.05， P<0.01）. Compared with the AS-Ⅳ group， Erastin+AS-Ⅳ group showed increased cell proliferation， increased iron deposition in cells， increased ROS and MDA contents， and decreased expression of SLC7A11 and GPX4 proteins（P<0.05）. Compared with the Erastin group， the cell proliferation in Erastin+AS-Ⅳ group was inhibited， the iron deposition was decreased， the contents of ROS and MDA were decreased， and the expression levels of SLC7A11 and GPX4 proteins were increased（P<0.05， P<0.01）. ConclusionAS-Ⅳ can inhibit ferroptosis by regulating the SLC7A11/GPX4 pathway， so as to weaken the proliferation of VSMCs， thus playing a role in the treatment of atherosclerosis.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. 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 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.