1.Resolution Assessment in Super-resolution Optical Microscopy: Adaptive Methods and Recent Advances
San-Hua FANG ; Jing-Yao CHEN ; Dan YANG ; Li LIU
Progress in Biochemistry and Biophysics 2026;53(4):805-825
Optical microscopy is essential for exploring biological and material structures, with resolution determining the level of observable detail. The advent of super-resolution fluorescence microscopy has broken the diffraction limit, achieving nanoscale resolution. However, traditional assessment methods, such as the Rayleigh criterion and point spread function (PSF) width measurement, rely on empirical judgments and diffraction-limited models, rendering them inadequate for modern super-resolution imaging. This review systematically traces the evolution of resolution assessment methodologies, from classical criteria to advanced strategies tailored for various super-resolution modalities. We first discuss Fourier-based quantitative methods. Fourier ring correlation (FRC) and its 3D counterpart, Fourier shell correlation (FSC), objectively determine resolution by evaluating the statistical correlation of two independent image reconstructions in frequency space. These methods offer robustness against noise and provide a global resolution metric, but they require data independence and are computationally intensive. They have become the prevailing standards in electron and super-resolution microscopy. Subsequently, we examine adaptations for specific super-resolution techniques. For single-molecule localization microscopy (SMLM) techniques such as PALM and STORM, the Fourier image resolution (FIRE) method extends FRC by incorporating a physical model that accounts for localization precision and labeling density. For stimulated emission depletion (STED) microscopy and other nonlinear techniques, assessment strategies differ. While PSF shrinkage measurements using fluorescent beads are useful for system calibration, evaluating the effective resolution directly on biological samples is more practical. This is typically performed via linewidth analysis of known structures (e.g., microtubules) or edge-spread function measurements, capturing the effects of photobleaching and sample-induced aberrations. A major paradigm shift is parameter-free resolution estimation based on decorrelation analysis. This method analyzes the autocorrelation decay of a single image’s Fourier spectrum to identify the cutoff spatial frequency without requiring dual datasets or user-defined thresholds. Its high efficiency and broad applicability have been validated across widefield, confocal, STED, SIM, and SMLM modalities. Optimized rendering strategies for SMLM data further enhance its accuracy, and it is emerging as a tool for real-time optimization of experimental parameters. The review also addresses the “gold standard” of resolution validation using well-defined nanostructures, such as DNA origami and nuclear pore complexes, which provide ground truth for verifying resolution claims and detecting artifacts. In the era of artificial intelligence, deep learning plays a dual role: it powerfully enhances image resolution but also introduces challenges, as models may generate “hallucinations” or false details. This underscores the need for new validation metrics to verify the physical fidelity of AI-generated content. Finally, we outline future directions: developing unified cross-modality standards, enabling real-time dynamic resolution monitoring for live-cell imaging, creating techniques for generating local resolution maps to capture sample heterogeneity, and integrating intelligent error correction to ensure data veracity. By providing a comprehensive overview of resolution assessment progress and challenges, this review aims to equip researchers with the knowledge to select appropriate tools, thereby fostering rigorous quantitative imaging in the life and material sciences.
2.Profiling the chemical differences of diterpenoid alkaloids in different processed products of Aconiti Lateralis Radix Praeparata by UHPLC-LTQ-Orbitrap mass spectrometry combined with untargeted metabolomics and mass spectrometry imaging.
Yang YU ; Changliang YAO ; Jianqing ZHANG ; Yong HUANG ; Shuai YAO ; Hua QU ; Tong ZHANG ; Dean GUO
Chinese Journal of Natural Medicines (English Ed.) 2025;23(8):1009-1015
Aconiti Lateralis Radix Praeparata (Fuzi) represents a significant traditional Chinese medicine (TCM) that exhibits both notable pharmacological effects and toxicity. Various processing methods are implemented to reduce the toxicity of raw Fuzi by modifying its toxic and effective components, primarily diterpenoid alkaloids. To comprehensively analyze the chemical variations between different Fuzi products, ultra-high performance liquid chromatography-linear ion trap quadrupole Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) was employed to systematically characterize Shengfuzi, Heishunpian and Baifupian. A total of 249 diterpenoid alkaloids present in Shengfuzi were identified, while only 111 and 61 in Heishunpian and Baifupian were detected respectively, indicating substantial differences among these products. An untargeted metabolomics approach combined with multivariate statistical analysis revealed 42 potential chemical markers. Through subsequent validation using 52 batches of commercial Heishunpian and Baifupian samples, 8 robust markers distinguishing these products were identified, including AC1-propanoic acid-3OH, HE-glucoside, HE-hydroxyvaleric acid-2OH, dihydrosphingosine, N-dodecoxycarbonylvaline and three unknown compounds. Additionally, the MS imaging (MSI) technique was utilized to visualize the spatial distribution of chemical constituents in raw Fuzi, revealing how different processing procedures affect the chemical variations between Heishunpian and Baifupian. The distribution patterns of different diterpenoid alkaloid subtypes partially explained the chemical differences among products. This research provides valuable insights into the material basis for future investigations of different Fuzi products.
Diterpenes/chemistry*
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Alkaloids/chemistry*
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Chromatography, High Pressure Liquid/methods*
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Aconitum/chemistry*
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Drugs, Chinese Herbal/chemistry*
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Metabolomics
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Mass Spectrometry/methods*
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Plant Roots/chemistry*
;
Molecular Structure
3.Clinical characteristics of postoperative patients with suspected infections in the intensive care unit:a multi-center cohort study of China
Shuguang YANG ; Yao SUN ; Ting WANG ; Hua ZHANG ; Fengxue ZHU ; Youzhong AN ; Huiying ZHAO
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2025;32(3):279-285
Objective To investigate mortality risk factors and characterize pathogen distribution and antimicrobial resistance patterns in intensive care unit(ICU)patients with suspected infection following surgery.Methods A total of 65 hospitals in 16 provinces in China from July 1,2021,to December 31,2022.Clinical data were collected for surgical patients transferred to the ICU with suspected infection.Data included demographics[sex,age,underlying conditions(hypertension,diabetes,cardiovascular/cerebrovascular disease,hematologic disease)],surgical site,infection site,microbiological results with susceptibility testing,drug resistance and acute physiology and chronic health evaluationⅡ(APACHEⅡ)scores and the length of hospital stays.Patients were stratified by prognosis into death group and survial group,by drug resistance status into resistant and non-resistant groups.Univariate and multivariate Logistic regression identified risk factors for mortality and antimicrobial resistance.Draw the receiver operator characteristic curve(ROC curve)to evaluate the predictive value of each risk factor for patient prognosis and drug resistance occurrence.Results A total of 677 patients with suspected postoperative infection in the ICU were enrolled.There were 96 deaths and 591 survivors.① Analysis of risk factors affecting prognosis:univariate analysis showed that compared with the survival group,the patients in the had a higher APACHEⅡscore,the proportion of patients with previous cerebrovascular disease,surgery sites in the abdomen,chest,brain,pelvis,limbs,other areas,as well as those with pulmonary infection,bloodstream infection,urinary tract infection,Gram-positive bacterial infection(Candida),fungal infection,multi-drug resistant bacterial infection was higher,and the length of hospital stay was shorter(all P<0.05).Multivariate Logistic regression analysis identified higher APACHEⅡscore[odds ratio(OR)=1.15,95%confidence interval(95%CI)was 1.11-1.20],pulmonary infection(OR=4.07,95%CI was 2.05-8.11),bloodstream infection(OR=2.61,95%CI was 1.52-4.51),and urinary tract infection(OR=2.20,95%CI was 1.01-4.42)were independent risk factors for prognosis(all P<0.05).The ROC curve analysis showed that the death risk prediction model established based on the above independent risk factors had certain predictive value for the prognosis of ICU postoperative patients with suspected infection,area under the curve(AUC)=0.820,95%CI was 0.770-0.860,P<0.05.②Regarding antimicrobial resistance:250 patients developed resistance and 427 did not.Univariate analysis showed compared with the non-resistant group,the APACHEⅡscore,the proportion of patients with cerebrovascular diseases,hematological diseases,surgeries at chest,brain,limbs,other sites,as well as those with pulmonary infection,bloodstream infection,urinary tract infection,intracranial infection,Gram-negative bacillus infection,and Gram-positive cocci infection(Staphylococcus epidermidis,Staphylococcus aureus,Enterococcus faecalis),and the mortality rate in the resistant group were significantly higher,the proportion of patients with surgeries at abdominal cavity,pelvic cavity and abdominal cavity infection were significantly lower,and the length of hospital stay was significantly longer(all P<0.05).Multivariate Logistic regression analysis bloodstream infection(OR=4.00,95%CI was 2.22-7.19),urinary tract infection(OR=3.25,95%CI was 1.47-7.17),Klebsiella pneumoniae infection(OR=2.23,95%CI was 11.22-44.02),Acinetobacter baumannii infection(OR=48.12,95%CI was 20.10-115.17),Pseudomonas aeruginosa infection(OR=34.06,95%CI was 13.00-89.25),Escherichia coli infection(OR=24.97,95%CI was 10.55-59.13),Stenotrophomonas maltophilia infection(OR=19.04,95%CI was 3.30-109.96),and Staphylococcus aureus infection(OR=13.48,95%CI was 4.57-39.78)were independent risk factors for resistance(all P<0.01).The ROC curve analysis showed that the predictive model for drug resistance established based on the above independent risk factors had certain predictive value for drug resistance in adult patients with suspected infections after surgery in the ICU.The AUC=0.920,95%CI was 0.890-0.940,P<0.05.Conclusion Higher APACHEⅡscores and the presence of pulmonary,bloodstream,or urinary tract infections were associated with increased mortality in ICU patients with suspected postoperative infection.Patients with bloodstream or urinary tract infections,or infections caused by Klebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa,Escherichia coli,Stenotrophomonas maltophilia,or Staphylococcus aureus,had significantly higher odds of developing antimicrobial resistance.
4.Effects of Rutong Ruanjian Tablets on angiogenesis in a rat model of preneoplastic breast cancer of Liver-Qi Stagnation and Blood Stasis Pattern via DLL4/Notch1/Hes1 pathway
Hua YANG ; Jun-yao LONG ; Jie GONG ; Bing-bing LU ; Xi ZOU ; Yu-rong WU ; Li-fang LIU ; Hui LIU ; Qi-hua CHEN
Chinese Traditional Patent Medicine 2025;47(3):774-781
AIM To investigate the effects of Rutong Ruanjian Tablets on angiogenesis in cancer tissues of rats with preneoplastic breast cancer(PBC).METHODS 60 female SD rats were randomly divided into a blank group of 10 rats and a model group of 50 rats for the establishment of the PBC models of Liver-Qi Stagnation and Blood Stasis Pattern with 9 weeks of oral administration of 7,12-dimethylbenz[a]anthracene(DMBA)and cervical ligation.After successful modeling,the rats were randomly divided into the model group,the tamoxifen group(3.2 mg/kg),the Rutong Ruanjian Tablets group(128 mg/kg),the 3,5-difluorobenzoyl group(DAPT,5 mg/kg),and the Rutong Ruanjian Tablets(128 mg/kg via gavage)+DAPT(5 mg/kg intraperitoneal injection)group,for 1 month corresponding drug administration,with 10 rats in each group.Then the rats had their cancer progression and syndrome scores observed;their angiogenesis evaluated by assessment of microvascular density(MVD);their vascular endothelial growth factor(VEGF)expression assessed by immunohistochemistry;and their mRNA and protein expressions of proteins related to the DLL4/Notch1/Hes1 pathway measured using RT-qPCR,immunohistochemistry and Western blot.RESULTS During carcinogenesis of rats induced by DMBA,there was gradual disappearance of E-cadherin expression and consistency of HE staining result with the PBC progression confirming the success of the modeling.Compared with the blank group,the model group showed increased MVD values,mRNA expression of Notch1 and Hes1,and protein expressions of VEGF,DLL4,Notch1 and Hes1(P<0.05,P<0.01).Compared with the model group,the Rutong Ruanjian Tablets group exhibited reduced MVD values,mRNA expression of Notch1 and Hes1,and protein expressions of VEGF,DLL4,Notch1 and Hes1(P<0.05,P<0.01).The Rutong Ruanjian Tablets+DAPT group showed reduced mRNA expression of Notch1 and Hes1,and protein expressions of DLL4,Notch1 and Hes1 compared to the Rutong Ruanjian Tablets group(P<0.05,P<0.01).CONCLUSION Rutong Ruanjian Tablets can inhibit angiogenesis and attenuate cancer progression in PBC rats of Liver-Qi Stagnation and Blood Stasis Pattern,and the mechanism may lie in the downregulation of DLL4/Notch1/Hes1 signaling pathway related proteins.
5.The impact of medical insurance payment reform on medical services and costs:A case study of Jinhua
Miao YU ; Ze-yao LI ; Hong-wu TUO ; Yan-sui YANG ; Guan-pin WU ; Hua-qiang JIN ; Xiao-zhou JIANG
Chinese Journal of Health Policy 2025;18(1):43-50
Objective:This study empirically analyzes the relationship between outpatient and inpatient services under the impact of healthcare payment reform,and evaluates the effects of the reform.Methods:Data from healthcare services and basic medical insurance payments in eight districts of Jinhua City from 2020 to 2022 were used.A fixed-effects model for outpatient and inpatient services was constructed to analyze the impact of healthcare payment reforms and outpatient services on inpatient services.Results:The DRG-based payment had a significant positive effect on inpatient visits and a significant negative effect on employee basic medical insurance inpatient costs.The"capitation+APG"outpatient payment policy had a significant negative effect on inpatient visits and a significant negative effect on residents'basic medical insurance inpatient costs.The interaction between outpatient payment and outpatient visits had a significant negative effect on employee basic medical insurance inpatient visits,while the interaction between outpatient payment and outpatient costs had a significant negative effect on both overall and employee inpatient costs.Conclusions:The DRG payment reform led to an increase in inpatient visits and a reduction in employee basic medical insurance inpatient costs.The outpatient"capitation+APG"payment reform reduced inpatient visits and lowered residents'basic medical insurance inpatient costs,thereby slowing down the complementary effect between outpatient and inpatient services.
6.ADAMS-based dynamic simulation analysis of surgical robot for pedicle screw placement
Li-hua YAO ; Zhi-ming CHE ; Xiang-rui MENG ; Shi-yang WU ; Yi-xun FANG
Chinese Medical Equipment Journal 2025;46(8):32-37
Objective To carry out a dynamic simulation analysis on the surgical process of the surgical robot for pedicle screw placement so as to enhance the safety of the procedure.Methods Firstly,the process of pedicle screw placement were analyzed to determine the three typical force conditions during pedicle screw track drilling including no-load condition,bone layer switching condition and spine dynamic displacement condition.Secondly,a virtual protype model of the surgical robot for pedicle screw placement was constructed with the automated dynamic analysis of mechanical systems(ADAMS).Finally,the dynamic characteristics of the surgical robot were simulated and analyzed with considerations on the three typical force conditions.Results The driving torque of the robot joints was sensitive to the load applied to the end of the opener mechanism under a wide range of operating conditions.Conclusion The surgical robot meets the requirements for pedicle screw placment,and a new idea is provided for enhancing the accuracy of pedicle screw placement.[Chinese Medical Equipment Journal,2025,46(8):32-37]
7.Endosomal catabolism of phosphatidylinositol 4,5-bisphosphate is fundamental in building resilience against pathogens.
Chao YANG ; Longfeng YAO ; Dan CHEN ; Changling CHEN ; Wenbo LI ; Hua TONG ; Zihang CHENG ; Yanling YAN ; Long LIN ; Jing ZHANG ; Anbing SHI
Protein & Cell 2025;16(3):161-187
Endosomes are characterized by the presence of various phosphoinositides that are essential for defining the membrane properties. However, the interplay between endosomal phosphoinositides metabolism and innate immunity is yet to be fully understood. Here, our findings highlight the evolutionary continuity of RAB-10/Rab10's involvement in regulating innate immunity. Upon infection of Caenorhabditis elegans with Pseudomonas aeruginosa, an increase in RAB-10 activity was observed in the intestine. Conversely, when RAB-10 was absent, the intestinal diacylglycerols (DAGs) decreased, and the animal's response to the pathogen was impaired. Further research revealed that UNC-16/JIP3 acts as an RAB-10 effector, facilitating the recruitment of phospholipase EGL-8 to endosomes. This leads to a decrease in endosomal phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and an elevation of DAGs, as well as the activation of the PMK-1/p38 MAPK innate immune pathway. It is noteworthy that the dimerization of UNC-16 is a prerequisite for its interaction with RAB-10(GTP) and the recruitment of EGL-8. Moreover, we ascertained that the rise in RAB-10 activity, due to infection, was attributed to the augmented expression of LET-413/Erbin, and the nuclear receptor NHR-25/NR5A1/2 was determined to be indispensable for this increase. Hence, this study illuminates the significance of endosomal PI(4,5)P2 catabolism in boosting innate immunity and outlines an NHR-25-mediated mechanism for pathogen detection in intestinal epithelia.
Animals
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Caenorhabditis elegans/genetics*
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Endosomes/immunology*
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Caenorhabditis elegans Proteins/immunology*
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Phosphatidylinositol 4,5-Diphosphate/immunology*
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Immunity, Innate
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Pseudomonas aeruginosa/immunology*
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rab GTP-Binding Proteins/genetics*
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Diglycerides/metabolism*
8.Current analysis of bloodstream infections in adult intensive care unit patients: a multi-center cohort study of China.
Shuguang YANG ; Yao SUN ; Ting WANG ; Hua ZHANG ; Wei SUN ; Youzhong AN ; Huiying ZHAO
Chinese Critical Care Medicine 2025;37(3):232-236
OBJECTIVE:
To analyze the clinical characteristics, microbiological analysis, and drug resistance patterns of intensive care unit (ICU) bloodstream infection.
METHODS:
A prospective cohort study method was employed to collect clinical data from patients suspected of bloodstream infection (BSI) during their stay in ICUs across 67 hospitals in 16 provinces and cities nationwide, from July 1, 2021, to December 31, 2022. Electronic data collection technology was used to gather general information on ICU patients, including gender, age, length of hospital stay, as well as diagnostic results, laboratory tests, imaging studies, microbiological results (including smear, culture results, and pathogen high-throughput testing), and prognosis. Patients were divided into a BSI group and a non-BSI group based on the presence or absence of BSI; further, patients with BSI were categorized into a drug-resistant group and a non-drug-resistant group based on the presence or absence of drug resistance. Differences in the aforementioned indicators between groups were analyzed and compared; variables with P < 0.10 in the univariate analysis were included in a multivariate Logistic regression analysis to identify risk factors for mortality and drug resistance in ICU patients with BSI.
RESULTS:
A total of 2 962 ICU patients suspected of BSI participated in the study, including 790 in the BSI group and 2 172 in the non-BSI group. Patients in the BSI group were mainly from East China and Southwest China, with significantly higher age and mortality rates than those in the non-BSI group. Among ICU patients with BSI, Staphylococcus had the highest detection rate (8.10%), followed by Klebsiella pneumoniae (7.47%); there were 169 cases in the drug-resistant group and 621 cases in the non-drug-resistant group; 666 cases survived, and 124 cases died (mortality was 15.70%). There were statistically significant differences between the death group and the survival group in terms of age, regional distribution, and bloodstream infections caused by Gram negative (G-) bacilli, Enterococcus faecium, Aspergillus, and Klebsiella pneumoniae; multivariate Logistic regression analysis showed that age [odds ratio (OR) = 1.01, 95% confidence interval (95%CI) was 1.00-1.03], regional distribution (OR = 4.07, 95%CI was 1.02-1.34), Enterococcus faecium infection (OR = 3.64, 95%CI was 1.16-11.45), and Klebsiella pneumoniae infection (OR = 2.64,95%CI was 1.45-4.80) were independent risk factors for death in ICU patients with BSI (all P < 0.05). There were statistically significant differences between the drug-resistant group and the non-drug-resistant group in terms of age and bloodstream infections caused by Gram positive (G+) cocci and G- bacilli; multivariate Logistic regression analysis showed that age (OR = 1.01,95%CI was 1.00-1.03), G- bacilli infection (OR = 2.18, 95%CI was 1.33-3.59), Escherichia coli infection (OR = 0.28,95%CI was 0.09-0.84), and Enterococcus faecium infection (OR = 3.35, 95%CI was 1.06-10.58) were independent risk factors for drug resistance in ICU patients with BSI (all P < 0.05).
CONCLUSIONS
Bloodstream infections may increase the mortality of ICU patients. Older age, regional distribution, Enterococcus faecium infection and Klebsiella pneumoniae infection can increase the mortality rate of ICU patients with BSI; bloodstream infections caused by G- bacilli are prone to drug resistance, but have no significant impact on the mortality of ICU patients with BSI.
Adult
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Humans
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Bacteremia/microbiology*
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China/epidemiology*
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Cohort Studies
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Cross Infection/microbiology*
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Drug Resistance, Bacterial
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Intensive Care Units/statistics & numerical data*
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Prospective Studies
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Risk Factors
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Sepsis/microbiology*
9.Clinical characteristics of Klebsiella pneumoniae in adult intensive care unit:a nationwide multi-center cohort study in China
Shu-Guang YANG ; Yao SUN ; Ting WANG ; Hua ZHANG ; Wei SUN ; You-Zhong AN ; Hui-Ying ZHAO
Medical Journal of Chinese People's Liberation Army 2025;50(3):292-300
Objective To analyze the epidemiological distribution,microbiological characteristics,drug-resistance status,and risk factors for mortality in adult intensive care unit(ICU)patients with Klebsiella pneumoniae infection.Methods This multi-center prospective cohort study included ICU patients with suspected infection from 67 hospitals across 16 Chinese provinces/municipalities between July 1,2021 and December 31,2022.Clinical data and microbiological results were collected,and patients were divided into survival and non-survival groups according to their survival status and drug-resistance situation.Risk factors for mortality and drug resistance in ICU patients with Klebsiella pneumonia infection were determined through univariate and multivariate logistic regression analyses.Results A total of 2964 ICU-infected patients were enrolled,with 12 175 microbial specimens submitted for testing.Among these,487 specimens tested positive for Klebsiella pneumoniae.Ultimately,314 patients with Klebsiella pneumoniae infection were identified,primarily from lung infections,with a drug-resistance rate of 78.3%.The in-hospital mortality rate of ICU patients infected with Klebsiella pneumoniae was 19.8%.Univariate and multivariate logistic regression analyses revealed that older age(P=0.027),high drug-resistance rate(P=0.028),and low clinical-effectiveness rate(P<0.001)were independent risk factors for mortality in ICU patients infected with Klebsiella pneumoniae.Drug-resistance analysis showed that,compared with non-resistant cases,ICU patients with drug-resistant Klebsiella pneumoniae infection had lower pathogen-clearance rates(P=0.003),clinical-effectiveness rates(P=0.004),and antibiotic-effectiveness rates(P<0.010),and higher mortality rates(P=0.006).Patients with Klebsiella pneumoniae abdominal infection(P=0.003)and urinary tract infection(P=0.007)had higher drug-resistance incidences.There were no statistically significant differences in clinical-effectiveness rate,Klebsiella pneumoniae clearance,drug-resistance incidence,mortality rate,or hospital-stay length between patients with lung infection and those with non-lung infection of Klebsiella pneumoniae(P>0.05).Compared with patients with non-bloodstream infection,patients with bloodstream infection of Klebsiella pneumoniae had lower clinical-effectiveness rates(P=0.027)and higher mortality rates(P=0.021).Conclusions Older age,high drug-resistance rate,and low clinical-effectiveness rate are independent risk factors for mortality in ICU patients infected with Klebsiella pneumoniae.ICU patients with bloodstream infection of Klebsiella pneumoniae may have lower clinical-effectiveness rates and higher mortality rates.ICU patients with abdominal and urinary tract infections caused by Klebsiella pneumoniae are more likely to develop drug resistance.
10.Nontarget Screening and Identification of Novel Per-and Polyfluoroalkyl Substances in Cosmetics Using Ultra-High Performance Liquid Chromatography-High-Resolution Mass Spectrometry
Xin-Ling LI ; Tao YANG ; Wen-Yao LIANG ; Jian-Hua TAN ; Xian-Zhi PENG
Chinese Journal of Analytical Chemistry 2025;53(4):640-651,中插23-中插28
Cosmetics may be an important source of human exposure to per-and polyfluoroalkyl substances(PFASs),posing risks to human health.In this study,a nontarget screening method for PFASs in cosmetics was developed using ultra-high performance liquid chromatography-high-resolution mass spectrometry(UHPLC-Q-Orbitrap HRMS)based on the Kendrick mass defect(KMD).The sample was extracted by ultrasonic assisted extraction prior to being analyzed by UHPLC-Q-Orbitrap HRMS.Acquisition of HRMS data was achieved in both full scan and data-dependent(Full MS/dd MS2)mode.The data collected by HRMS were imported into an in-lab built R script for processing.Samples retained the mass spectra peaks with KMD values in the range of 0.85-1 or 0-0.15 for in-and out-of-library matching;when KMD deviation(δKMD)<0.001 and CF 2 mass error(δMS)<15 ppm,it was considered as a potential PFASs homologues.According to matches of parent ions(MS),fragment ions(MS2)and retention time(RT)with the in-house built PFASs database,the screened and identified potential PFASs were categorized to 5 confidence levels(CL1-CL5).A total of 15 kinds of PFASs homologues with confidence level of CL3 and above were screened from 13 cosmetics products and 8 cosmetic raw materials,including perfluoroalkyl alcohol,hydroperfluoroalkyl sulfonic acid,chloroperfluoroalkyl sulfonic acid,etc.with concentrations ranging from 1.9 ng/g to 98.1 ng/g.The nontarget screening method could be used to screen and identify PFASs homologues feasibly and therefore provided data basis for management and control of PFASs addition in cosmetics.

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