1.Establishment and validation of a model for femoral head necrosis after internal fixation of femoral neck fracture using logistic regression and SHAP analysis
Long LIAO ; Zepeng ZHAO ; Zongyuan LI ; Qinglong YU ; Tao ZHANG ; Jinyuan TANG ; Nan YE ; Han XU ; Bo SHI
Chinese Journal of Tissue Engineering Research 2026;30(3):626-633
BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95%Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2%and a specificity of 87.6%,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1%to 92%,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.
2.Establishment and validation of a model for femoral head necrosis after internal fixation of femoral neck fracture using logistic regression and SHAP analysis
Long LIAO ; Zepeng ZHAO ; Zongyuan LI ; Qinglong YU ; Tao ZHANG ; Jinyuan TANG ; Nan YE ; Han XU ; Bo SHI
Chinese Journal of Tissue Engineering Research 2026;30(3):626-633
BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95%Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2%and a specificity of 87.6%,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1%to 92%,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.
3.Prevalence of human T-lymphocyte leukemia virus among blood donors in Guangzhou
Yuxiao LI ; Xia RONG ; Bo HE ; Rongsong DU ; Zhengang SHAN ; Qiao LIAO
Chinese Journal of Blood Transfusion 2025;38(2):222-226
[Objective] To analyze the prevalence of human T-lymphocyte leukemia virus (HTLV) among blood donors in Guangzhou from 2016 to 2021, and provide a basis for blood collection and supply management in this region. [Methods] A total of 2 116 951 voluntary blood donors were screened for anti-HTLV by enzyme-linked immunosorbent assay (ELISA) from March 2016 to December 2021 in Guangzhou, and the reactive cases were further confirmed by Western blotting (WB). Qualitative data were analyzed by χ2 with spss19 software. The trend of the total positive rate of HTLV confirmation test by WB from 2016 to 2021 was analyzed with the Joinpoint software, and the annual percent change (APC) was used to determine whether the trend changes were statistically significant. [Results] From March 2016 to December 2021, the total positive rate for anti-HTLV by ELISA among voluntary blood donors in Guangzhou was 0.019 7% (416/ 2116 951), and the WB confirmed positive rate was 0.001 1% (23/2 116 951). The total positive rate of HTLV among individual voluntary blood donors in the six main districts (0.002 12%, 19/895 301) was higher than that among group voluntary blood donors (0.000 32%, 3/951 947) (P<0.05). There was no significant difference in the total positive rate of HTLV confirmation between the six main districts (0.001 19%) and the three non-main districts (0.000 37%) (P>0.05). The trend of the total positive rate of HTLV infection in the six main districts and the Guangzhou area(including the six main districts and three non-main districts) showed no significant increase or decrease. [Conclusion] The prevalence of HTLV among blood donors in Guangzhou remains at a low level.
4.National bloodstream infection bacterial resistance surveillance report 2023: Gram-positive bacteria
Chaoqun YING ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(2):118-132
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
5.National bloodstream infection bacterial resistance surveillance report (2023) : Gram-negative bacteria
Jinru JI ; Zhiying LIU ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(1):47-62
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.
6.Analysis of the efficacy of lamb′s tripe extract and vitamin B 12 capsule on chronic atrophic gastritis at different sites
Dongdong XIA ; Huahong XIE ; Bo JIANG ; Hong XU ; Zhanguo NIE ; Chengwei TANG ; Qiang GUO ; Xiaoping ZOU ; Shuisheng SHI ; Tao SUN ; Shourong SHEN ; Guoqing LI ; Xiaozhong GUO ; Xiaoyan ZHAO ; Jiaming QIAN ; Weixing CHEN ; Guiying ZHANG ; Aijun LIAO ; Jingyuan FANG ; Daiming FAN ; Kaichun WU
Chinese Journal of Digestion 2025;45(3):162-168
Objective:To evaluate the efficacy of lamb′s tripe extract and vitamin B 12 capsule (LTEVB 12C) on chronic atrophic gastritis (CAG) at different locations (antrum lesser curvature, antrum greater curvature, gastric angle, corpus lesser curvature, and corpus greater curvature). Methods:From August 2011 to January 2013, 715 patients with CAG in a multicenter, randomized, double-blind, placebo-controlled trial were enrolled from 16 tertiary first-class hospitals across the country, including the First Affiliated Hospital of Air Force Medical University, Nanfang Hospital of Southern Medical University, the First Hospital of Jilin University, West China Hospital of Sichuan University, etc., there were 476 cases in the LTEVB 12C group and 239 cases in the placebo group. The patients of the LTEVB 12C group received LTEVB 12C, and the patients of placebo group received LTEVB 12C mimetic, all the medications were taken 3 capsules each time and 3 times a day after meals, and the treatment course of 2 groups were both 6 months. The efficacy evaluation criteria included the effective rate (a decrease of ≥1 in histopathological score compared with baseline after 6 months of treatment) and the reversal rate (a decrease of ≥ 2 in histopathological score compared with baseline after 6 months of treatment in the patients with moderate to severe CAG). The impact of lesion sites on the therapeutic effects of LTEVB 12C was analyzed by logistic regression analysis. The two-way unordered Cochran-Mantel-Haenszel chi-square test considering the center effect and Pearson chi-square test were used for statistical analysis. Results:The effective rates of chronic inflammation at the antrum greater curvature and corpus greater curvature (23.3%, 110/473 vs. 13.0%, 31/239; 20.3%, 96/472 vs. 12.6%, 30/239), the effective rates of atrophy at the antrum lesser curvature, antrum greater curvature, gastric angle, corpus lesser curvature, and the corpus greater curvature (27.0%, 118/437 vs. 15.7%, 34/216; 29.2%, 126/432 vs. 18.5%, 38/205; 27.8%, 121/435 vs. 16.7%, 36/216; 32.5%, 127/391 vs. 19.8%, 37/187; 33.0%, 119/361 vs. 21.8%, 39/179), and the effective rates of intestinal metaplasia at the antrum lesser curvature, antrum greater curvature, gastric angle, and the corpus lesser curvature (45.0%, 112/249 vs. 29.8%, 31/104; 53.8%, 86/160 vs. 33.9%, 21/62; 45.8%, 103/225 vs. 24.0%, 25/104; 51.9%, 83/160 vs. 28.3%, 17/60) of the LTEVB 12C group were all higher than those of the placebo group, and the differences were statistically significant ( χ2=10.76, 6.39, 9.69, 7.91, 11.05, 9.62, 8.57, 5.20, 7.11, 12.45, and 6.73; all P<0.05). The reversal rates of chronic inflammation at the corpus lesser curvature and corpus greater curvature (5.2%, 12/231 vs. 0, 0/123; 4.7%, 8/170 vs. 0, 0/88), the reversal rates of atrophy at the antrum lesser curvature, antrum greater curvature, corpus lesser curvature, and the corpus greater curvature (6.8%, 22/323 vs. 1.3%, 2/151; 9.2%, 29/315 vs. 1.4%, 2/144; 14.2%, 38/267 vs. 2.5%, 3/121; 20.8%, 35/168 vs. 5.8%, 4/69), and the reversal rates of intestinal metaplasia at the antrum lesser curvature, antrum greater curvature, gastric angle, and the corpus lesser curvature (29.8%, 39/131 vs. 9.1%, 4/44; 41.0%, 32/78 vs. 12.5%, 3/24; 33.3%, 44/132 vs. 4.8%, 3/63; 50.0%, 37/74 vs. 8.7%, 2/23) of the LTEVB 12C group were all higher than those of the placebo group, and the differences were statistically significant ( χ2=6.58, 5.12, 5.60, 8.61, 11.43, 6.59, 7.30, 4.95, 15.92, 7.62; all P<0.05). There were no statistically significant differences in the effective rates and reversal rates of active inflammation at different locations between the LTEVB 12C group and the placebo group (all P>0.05). The results of logistic regression analysis (taking the antrum lesser curvature as the reference) further confirmed that the reversal rates of chronic inflammation ( OR=0.22, 95% confidence interval (95% CI): 0.07 to 0.67; OR=0.24, 95% CI: 0.07 to 0.80), atrophy ( OR=0.28, 95% CI: 0.16 to 0.49; OR=0.28, 95% CI: 0.16 to 0.49), and intestinal metaplasia ( OR=0.42, 95% CI: 0.24 to 0.77; OR=0.20, 95% CI: 0.08 to 0.52) at the corpus lesser curvature and corpus greater curvature were all higher than those at the antrum lesser curvature, and the differences were statistically significant (all P<0.05). There were no statistically siginificant differences in the reversal rates of the aforementioned pathological features between the antrum greater curvature, gastric angle, and the antrum lesser curvature (all P>0.05). Conclusion:LTEVB 12C can achieve good efficacy in the treatment of CAG, and the chronic inflammation, atrophy, and intestinal metaplasia at multiple locations are improved, especially at the corpus lesser curvature and the corpus greater curvature.
7.Interaction between shift work and occupational stress on occupational burnout among employees in power companies
Peifang LIU ; Bo SHEN ; Guofeng LI ; Jing LIAO ; Yifei LIU ; Sitong FANG ; Yu JIANG
Journal of Environmental and Occupational Medicine 2025;42(12):1415-1421
Background The power industry is characterized by typical shift work systems, with 24-hour uninterrupted work demands, high intensity and high standard job characteristics, as well as emergent task pressure, which exposes employees to the long-term dual pressure of shift work and occupational stress and may lead to occupational burnout. It not only endangers the physical and mental health of employees, but also threaten the safe and stable operation of the power system. Objective To explore the impact of shift work and occupational stress, as well as their potential interaction, on occupational burnout among employees in power enterprises. Methods From November 2024 to April 2025, cluster sampling was used to select
8.Proteomic Preparation Techniques for Formalin-Fixed Paraffin-Embedded Tissue Samples
Ao LU ; Bo MENG ; Jia-Wei ZHAO ; Huan-Yue LIAO ; Zi-Hong YE ; Xiang FANG ; Yang ZHAO
Chinese Journal of Analytical Chemistry 2025;53(1):84-93,中插4-中插8
Twelve pre-processing protocols for formalin-fixed paraffin-embedded(FFPE)tissue samples were developed by orthogonal experimental design,incorporating different dewaxing buffers(Triton X-100 and xylene),lysis buffers(TFE and RapiGest),and enzyme digestion methods(iST,SP3,and FASP)to explore the optimal experimental conditions.These protocols were assessed based on protein and peptide identification depth,identification stability,and quantitative levels of protein abundance.The results indicated that Triton X-100 and xylene minimally impacted proteomics identification,whereas the TFE lysis buffer and iST digestion method significantly enhanced the proteomics analysis of FFPE samples.Considering the potential toxicity of xylene,the TTI protocol based on Triton X-100,TFE,and iST was determined to be the optimal choice.This protocol exhibited the best repeatability and stability,and a higher number of proteins associated with significant biological functions were identified.In conclusion,the established TTI protocol offered an efficient and comprehensive approach for proteomic analysis of FFPE samples,significantly enhancing the repeatability and stability of protein identification.
9.Supramolecular Binding Behavior and Solubilization of Cationic Cyclodextrins towards Liquiritigenin
Ying-Hui DENG ; Dong-Jing ZHANG ; Hai-Kun WANG ; Jia-Xing CHEN ; Shuang SONG ; Bo YANG ; Xia-Li LIAO
Chinese Journal of Analytical Chemistry 2025;53(2):289-299,中插20-中插30
Liquiritigenin(LG)is a flavone of pharmacological importance,however,its application potential is severely limited due to its poor water solubility.LG could be disassociated slightly in water to form phenolate anion,therefore,better solubilization effect is expected by inclusion with cationic cyclodextrins(CCDs).In this work,four kinds of CCDs modified with amino groups at the primary face were synthesized,and their solid inclusion complexes with LG were successfully prepared by preparing their saturated solutions.The formation of the solid inclusion complexes was confirmed by scanning electron microscopy(SEM)and powder X-ray diffraction(PXRD),and their supramolecular binding behavior in solution was studied using multiple techniques.A 1∶1 inclusion stoichiometry of inclusion complexation was defined using Job plot by ultraviolet-visible(UV-vis)spectroscopy,and their binding stability constants(Ks)were determined as 2862.77,3494.70,6521.85 and 9599.48 L/mol using UV-vis spectroscopic titration,far more superior to that of nativeβ-CD(Ks=236.79 L/mol).This indicated that the amino side chains on CCDs could actively participate in the inclusion complexation through anion-cation interactions,significantly strengthening the host-guest binding between CCDs and LG.The inclusion modes were further elucidated based on proton and two-dimensional rotating-frame overhauser enhancement spectroscopy(2D-ROESY)nuclear magnetic resonance(NMR)experiments and molecular docking.Water solubility of LG was dramatically promoted up to 4.9 mg/mL,which was 70-fold higher than that of native LG.This study could draw inspiration for the binding and solubilization of phenols such as flavones by design of cationic macrocyclic molecules.
10.Quantification of Atmospheric Total Reactive Nitrogen Oxides by Thermal Decomposition-Broadband Cavity Enhanced Absorption Spectroscopy
Dou SHAO ; Min QIN ; Wu FANG ; Bao-Bin HAN ; Ke TANG ; Jian-Ye XIE ; Xia-Dan ZHAO ; Zhi-Tang LIAO ; En-Bo REN
Chinese Journal of Analytical Chemistry 2025;53(3):387-396
Nitrogen oxides(NOx=NO+NO2)are important precursors of ozone(O3),and NOx and its oxides together constitute reactive nitrogen oxides(NOy)in the atmosphere.A comprehensive understanding of the total NOy level in the atmosphere is of great significance for a deeper understanding of the atmospheric nitrogen cycle and oxidation,as well as for formulating strategies for air pollution prevention and control.In this work,a thermal decomposition-broadband cavity enhanced absorption spectroscopy(TD-BBCEAS)technique for online measurement of total NOy in the atmosphere was developed.With this method,the NOy was efficiently converted into NO2,and the total NOy concentration in the atmosphere was indirectly obtained by measuring NO2.Focusing on the key factors affecting the measurement of total NOy,the influence of NO titration efficiency and other NOy component TD efficiency on measurement accuracy was emphasized.By changing the oxygen(O2)flow rate through the mercury lamp to alter the O3 concentration for titrating NO,the conversion efficiency of NO was evaluated.At O2 flow rate of 6 mL/min,the conversion efficiency of NO was greater than 99%.TD efficiency testing and analysis on NO2,peroxyacetyl nitrate(PAN),nitric acid(HNO3),and nitrous acid(HONO),which account for a large proportion of atmospheric NOy components,was carried out using 680℃as the optimal TD temperature for efficient conversion of NOy.With NO and HONO sample gases as typical verification gases,the conversion efficiency of NOy and the accuracy of NOy measurement by TD-BBCEAS system were verified by switching the on and off modes of mercury lamp and TD device.At integration time of 60 s,the detection limit of the system for NOy was 2.83×1010 molecules/cm3(60 s,2σ).A comparative measurement of actual atmospheric NOy was conducted between the TD-BBCEAS system and the NOy analyzer.The observation results showed a correlation coefficient(R2)of 0.98 and a slope of 0.93,further verifying the feasibility and accuracy of applying the TD-BBCEAS system to measurement of total NOy.

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