Objective To evaluate the clinical efficacy of artificial intelligence(AI)-assisted imaging diagnostic trials using multi-reader multi-case(MRMC)design,so as to provide a scientific basis for clinical evaluation of imaging diagnostic trials.Methods The MRMC design,widely used in imaging diagnostic trials,was adopted in this study.The Obuchowski-Rockette(OR)method of MRMC design was detailed,including model construction and test methods.A case study was conducted,collecting imaging data of 200 subjects from 3 hospitals,with 133 cases of rib fractures and 68 cases of non-rib fractures.Three radiologists reviewed all CT images of the subjects.The area under curve(AUC)value,sensitivity and specificity in detecting rib fractures between 2 reading modalities(radiologists with AI assistance vs radiologists reading independently)were compared.Results The AI-assisted reading group had an AUC value of 0.958,while the radiologist-independent reading group had an AUC value of 0.902,showing a significant difference(P＜0.001).The overall sensitivity and specificity of the AI-assisted reading group were 0.970 and 0.946,respectively;while the sensitivity and specificity of the radiologist-independent reading group were 0.838 and 0.966,respectively.The difference of sensitivity between groups was 0.131(95％confidence interval[CI]0.091-0.171),and the difference of specificity was-0.020(95％CI-0.059-0.020),indicating a significant difference in sensitivity but not in specificity between AI-assisted and radiologist-independent reading groups.Both groups had positive likelihood ratios(+LR)greater than 10 and negative likelihood ratios(-LR)less than 0.2,with positive predictive values approaching 1,suggesting that the diagnostic accuracy of the AI-assisted imaging diagnostic trials was high.Conclusion The AI-assisted reading method demonstrates a significant advantage in enhancing diagnostic efficiency,not only improving the diagnostic accuracy and detection rate of rib fractures,but also improving the work efficiency of radiologists and optimizing hospital services.

Objective To estimate the sample size of radiological diagnostic tests in multireader multicase(MRMC)design,and to explore the numbers of readers and cases under 3 different inference situations:random-reader random-case,fixed-reader random-case,and random-reader fixed-case.Methods The images of 114 participants(45 cases diagnosed as aortic coarctation by the gold standard)in the Van Dyke dataset were used,and 5 radiologists read these images under 2 different magnetic resonance imaging(MRI)sequences(Spin-echo and Cine MRI)to obtain the pre-experiment data.Then Obuchowski-Rockette method was used to estimate sample size.Results The mean area under curve(AUC)of aortic coarctation determined by radiologists was 0.941(95%confidence interval[CI]0.899-0.983)with the Spin-echo MRI sequence,and 0.897(95%CI 0.837-0.957)with the Cine MRI sequence.When the effect size was 0.044 and the number of readers was 5,we needed 337 participants for random-reader random-case,162 participants for fixed-reader random-case,and 282 participants for random-reader fixed-case.Conclusion In MRMC design,we need both the number of readers and cases;the larger the number of readers,the smaller the cases required.We need more samples under the situation of random-reader random-case,when the number of readers is≥5.

Objective:To explore the digital design and fabrication technology of personalized restorative matrix for dental filling, and to explore the feasibility of direct resin restoration for deep caries lesions in distal neck of mandibular second molar.Methods:For patients with deep caries lesions in the distal neck of the mandibular second molar who visited the Department of Cariology and Endodontology of Peking University School and Hospital of Stomatology from September 2023 to April 2024, after preparing the cavity and gingival retractor, a three-dimensional intraoral scanner was used to obtain three-dimensional data of the patient′s dentition. In the dental restoration computer-aided design software, the inlay function was used to generate the restored tooth morphology. The edge range of the personalized restorative matrix was drawn on the restored model by three-dimensional reverse engineering software to achieve edge sealing effect. The selected edge range data was processed with distal shelling to generate a digital model of a personalized restorative matrix with a thickness of 0.5 mm. A metal three-dimensional printer was used to fabricate the titanium alloy restorative matrix, and its application was completed in 10 clinical cases. The marginal adaptation and retention stability of the personalized restorative matrix were evaluated under a dental microscope, and forming effect evaluation was performed through immediate postoperative periapical radiographs.Results:The preliminary clinical application of the personalized restorative matrix fabricated using digital technology revealed that, in the treatment of 10 affected teeth, rubber dam isolation was successfully ensured, resulting in clinically effective direct resin composite restorations with optimal marginal adaptation and reasonable contours. Immediate postoperative periapical radiographs showed good convexity of the filling body, with no overhangs found. Both marginal adaptation and retention stability met the requirements of clinical treatment.Conclusions:The personalized restorative matrix designed in this study can solve the clinical problems of moisture separation and resin forming in the treatment of deep caries lesions in distal neck of the mandibular second molar, and can achieve stable and reliable adhesive restoration effects.

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

Objective:To investigate molecules involved in the occurrence of pruritus in patients with mycosis fungoides (MF) .Methods:Totally, 522 patients with MF were enrolled from Peking University First Hospital from October 2009 to August 2021, and the incidence of pruritus was calculated. The patients were grouped according to whether they suffered from pruritus or not. RNA sequencing data on biopsied skin lesions of 49 patients were analyzed to identify differentially expressed genes between patients with pruritus and those without; enzyme-linked immunosorbent assay and immunohistochemical techniques were performed to determine the protein expression of CC chemokine ligand 17 (CCL17) in serum samples from 88 MF patients, and in tissue samples from 81 MF patients, respectively; flow cytometry was conducted to detect markers for T lymphocyte activation and differentiation in peripheral blood samples from 46 MF patients to identify peripheral blood lymphocyte subsets associated with pruritus. Statistical analysis was carried out by using chi-square test, Mann-Whitney U test, and Spearman correlation analysis. Results:Among the 522 patients with MF, 305 were males and 217 were females; 347 were diagnosed with early-stage MF, and 175 with advanced MF. The incidence of pruritus was 67.2% (351/522) in the patients with MF, and significantly higher in the patients with advanced MF (81.7%, 143/175) than in those with early-stage MF (59.9%, 208/347; χ2 = 25.03, P < 0.001) . RNA sequencing showed that CCL17 mRNA expression was significantly higher in the MF patients with pruritus than in those without (fold change = 10.09, P < 0.001) . The serum CCL17 concentration was significantly elevated in the patients with pruritus (1 017.05[377.12, 4 831.80] pg/ml) compared with those without (361.66 [180.47, 500.08] pg/ml; Z = -4.57, P < 0.001) , and correlated with pruritus scores ( r = 0.57, P = 0.010) . In both early and advanced stages of MF, the serum CCL17 concentration was significantly higher in the patients with pruritus than in those without ( Z = -3.68, P < 0.001; Z = -2.54, P = 0.011, respectively) . Immunohistochemical staining revealed that there was no significant difference in the relative quantification value of CCL17 between the patients with pruritus and those without ( Z = -1.84, P = 0.066) . The percentage of CD3 +CD4 +CD26 -CCR4 + malignant T cells significantly increased in the MF patients with pruritus than in those without ( Z = -2.03, P = 0.043) , and was positively correlated with serum CCL17 concentrations ( r = 0.49, P < 0.001) . Conclusions:Both CCL17 mRNA expression in lesional tissues and serum CCL17 concentrations increased in MF patients with pruritus, and CCL17 was associated with the occurrence of pruritus. CCL17 may be involved in the occurrence of pruritus through the recruitment of CD3 +CD4 +CD26 -CCR4 + malignant T cells.

Objective:To determine lysophosphatidic acid receptor 6 (LPAR6) expression in patients with mycosis fungoides (MF) , a variant of cutaneous T-cell lymphoma (CTCL) , and to investigate its role and mechanism of action in the development and prognosis of CTCL.Methods:A total of 110 patients with confirmed MF were collected from Department of Dermatology, Peking University First Hospital from 2011 to 2020, including 24 with large-cell transformation (LCT) and 25 with non-large cell transformation (NLCT) in the discovery cohort, and 24 with LCT and 37 with NLCT in the validation cohort. RNA sequencing and RT-PCR were conducted to determine the LPAR6 expression in patients in the discovery cohort and validation cohort respectively. LPAR6 expression was compared between patients with LCT and those with NLCT, and its effect on the prognosis of patients was evaluated. Two LPAR6-overexpressing CTCL cell lines MyLa and Sz4 were constructed to evaluate the effect of LPAR6 overexpression on proliferative activity of MyLa and Sz4 cells, with the cells normally expressing LPAR6 as the control group; after the treatment with LPAR6-related ligand lysophosphatidic acid (LPA) , 2S-OMPT, adenosine triphosphate (ATP) or adenosine (ADO) , the effects of LPAR6 activation on the proliferative activity and apoptosis of LPAR6-overexpressing MyLa and Sz4 cells were evaluated by the MTS method and flow cytometry respectively. Log-rank test was used for prognostic analysis, and t test or Mann-Whitney U test was used for comparisons between two groups. Results:As RNA sequencing showed, LPAR6 was one of the significantly underexpressed genes in the LCT group in the discovery cohort; in the validation cohort, LPAR6 expression (median[ Q1, Q3]) was significantly lower in the LCT group (204.90[81.90, 512.70]) than in the NLCT group (809.40[417.50, 1 829.20], U= 242.00, P= 0.002) ; in the two cohorts, the underexpression of LPAR6 was significantly associated with increased risk of poor prognosis (both P < 0.01) . Cell proliferation assay showed no significant difference in the proliferative activity of MyLa or Sz4 cells between the LPAR6 overexpression group and control group at 0, 24, 48 and 72 hours during the experiment (all P > 0.05) ; 48 hours after activation of LPAR6 by LPA, 2S-OMPT, ATP and ADO in MyLa cells, the LPAR6 overexpression group showed significantly decreased cellular proliferative activity (1.38 ± 0.01, 1.04 ± 0.01, 1.09 ± 0.03, 1.23 ± 0.01, respectively) compared the control group (1.73 ± 0.04, 1.23 ± 0.01, 1.24 ± 0.01, 1.42 ± 0.03, t= 30.33, 18.38, 4.78, 5.75, respectively, all P < 0.05) , but significantly increased cell apoptosis rate (17.93% ± 0.88%, 17.75% ± 0.35%, 23.97% ± 0.57%, 31.44% ± 0.34%, respectively) compared the control group (3.98% ± 0.03%, 7.81% ± 0.59%, 11.95% ± 0.85%, 12.02% ± 0.48%, t= 15.93, 14.49, 11.74, 33.01, respectively, all P < 0.05) ; 48 hours after activation of LPAR6 by 2S-OMPT and ADO in Sz4 cells, compared with the control group, the LPAR6 overexpression group also showed significantly decreased cellular proliferative activity (2S-OMPT: 1.29 ± 0.04 vs. 1.48 ± 0.01; ADO: 1.27 ± 0.01 vs. 1.51 ± 0.02; both P < 0.05) , but significantly increased cell apoptosis rate (2S-OMPT: 41.70% ± 0.70% vs. 29.35% ± 0.55%; ADO: 37.05% ± 0.15% vs. 24.60% ± 1.00%; both P < 0.05) . Conclusions:LPAR6 was underexpressed in the patients with LCT, and its underexpression was significantly associated with increased risk of poor prognosis. In vitro activation of LPAR6 could inhibit the proliferation of CTCL cells and promote their apoptosis, suggesting that the decrease of LPAR6 expression may be one of the important mechanisms underlying disease progression in patients with LCT.

Objective:To establish the quality standard for Sinapis Semen( stir-baked) formula granule. Methods:TLC was used to identify Sinapis Semen; an HPLC method was applied in the content determination of Sinapine thiocyanate in Sinapis Semen ( stir-baked) formula granule with Hibar Purospher STAR C18 (250 mm × 4. 6 mm,5 μm ) column and with the mobile phase consisting of acetonitrile-0. 08 mol·L-1 potassium dihydrogen phosphate (10 ∶90) at the flow rate of 1. 0 ml·min-1 ,the column temperature was 35℃ and the detection wavelength was set at 326 nm. Results:The characteristic spots of Sinapis Semen( stir-baked) formula granule were clearly detected by the established TLC chromatography. Sinapine thiocyanate had a good linear relationship within the concentra-tion range of 0. 012 2-3. 912 3μg(r=0. 999 9). The average recovery was 100. 4% (RSD=0. 6%, n=6). The water content, dis-solution and particle size of Sinapis Semen formula granule all met the related requirements. Conclusion:The methods are simple and accurate with good reproducibility,which can be used to control the quality of Sinapis Semen( stir-baked) formula granule.

Objective To evaluate the relationship between extracellular signal-regulated kinase (ERK)and ketamine-induced apoptosis in rat hippocampal neurons.Methods Sprague-Dawley rats at 18 days of gestation were anesthetized.The fetal rats were obtained under the sterile condition and decapitated.The hippocampal neurons were isolated and primarily cultured for 5 days,and were seeded in 6-well plates (2 ml/well) or in 96-well plates (100μl/well) at a density of 5 × 105/ml.The cells were randomly divided into 4 groups (n =18 each):control group (group C),fibroblast growth factor (FGF-2,an ERK agonist) group (group F),ketamine group (group K) and FGF-2 + ketamine group (group FK).The cells were cultured in the plain culture medium in group C.FGF-2 50 ng/ml was added to the culture medium in group F.Ketamine was added to the culture medium in group K.FGF-2 50 ng/ml was added to the culture medium at 20 min before ketamine 100 μmol/L was added in group FK.The phosphorylation of ERK in hippocampal neurons was detected by Western blot at 10 min after treatment.At 24 h after treatment,the neuronal apoptosis was detected by Hoechst33342/PI staining,and the cell survival rate was detected by MTT assay.The apoptosis rate was calculated.Results Compared with group C,the phosphorylation of ERK in hippocampal neurons and the cell survival rate was significantly decreased and the apoptosis rate was increased in K and FK groups (P ＜ 0.05).There was no significant difference in the parameters mentioned above between F and C groups (P ＞ 0.05).The phosphorylation of ERK in hippocampal neurons and the cell survival rat was significantly higher and the apoptosis rate was lower in group FK than in group K (P ＜0.05).Conclusion Ketamine induces apoptosis in rat hippocampal neurons by inhibiting activation of ERK in hippocampal neurons.

Objective: In this paper the pharmacodynamical mechanism of Heat Asthma Formula(HAF)(Herba Ephedrae, Rhizoma pinelliae, Flos Lonicerae, etc) in the treatment of bronchial asthma was discussed. Methods: By means of the radio labelled aglycone, applying phlogistic medium TXB2, ? receptor on bronchus and cyclic nucleotide (cAMP/cGMP) in lung tissue used as observed targets. Results: The results showed HAF could inhibit the release of phlogistic medium TXB2, improve the conjugate rate of ? receptor, adjust the proportion between cAMP and cGMP. Conclusion: The treatment on bronchial asthma of “Heat Asthma Formula” was perhaps concerned with above mentioned contents.