Objective:This study aimed to evaluate to evaluate the performance of equilibrium dialysis combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the accurate measurement of free testosterone in clinical samples. Mthods We conducted a prospective observational study using 161 serum samples from healthy women of reproductive 26(24, 32)years at the Gynecology Outpatient department of Peking Union Medical College Hospital from June to September 2024, and their concentrations were determined. In this study, after equilibrium dialysis of serum samples, free testosterone was extracted from the dialysate using a magnetic bead-based method. It was then directly derivatized using hydroxylamine hydrochloride in situ after elution from the magnetic bead and further quantified by LC-MS/MS.Method:validation assessed linearity, limit of quantification (LOQ), precision, accuracy, matrix effects, and carryover according to established guidelines. Data were analyzed using Origin 2019 and WPS Office 2019.Results:The method demonstrated excellent linearity ( R2>0.99) across 1-250 pg/ml with an LOQ of 1 pg/ml. The coefficients of variation for both intra-day and inter-day imprecision were less than 10% while recovery rates ranged from 92.60% to 99.10%. Matrix effect deviations were all within the range of 6% and carryover was negligible. Conclusions:In this study, the established method of magnetic bead-based extraction followed by in situ derivatization combined with liquid chromatography-tandem mass spectrometry performed well, and could be further applied to the detection of free testosterone concentration in childbearing age women.

Surgical intervention for malignant bone tumors frequently results in bone defects located at the metaphysis of the long bones in the lower extremities.The morphological heterogeneity of the metaphysis poses significant challenges for conventional treatment methods to adequately conform to the defect area.The utilization of three-dimensional(3D)-printed titanium bone repair scaffolds has emerged as an effective reconstructive approach for metaphyseal bone defects,as these scaffolds offer precise shape conformity and provide adequate mechanical support.However,the current commonly used scaffolds do not adequately replicate the biomechanical environment of bone defects,resulting in suboptimal bone ingrowth within the scaffolds and subsequent prosthesis loosening and failure post-operation.Bone is a highly force-responsive organ,and its fate is regulated by biomechanical signals.Consequently,designing scaffolds with consideration of biomechanical principles to ensure mechanical compatibility between the scaffolds and the bone defect sites is a critical factor influencing the success of bone defects reconstruction.This review primarily introduces the biomechanical factors influencing bone defect repair and the advancements in designing 3D-printed titanium bone repair scaffolds biomechanically matched with bones,offering theoretical guidance for scaffold design and preparation.

Objective To evaluate the effectiveness of active screening in improving the detection rate of carbape-nem-resistant Enterobacterales(CRE)in the intensive care units(ICUs).Methods From July 2023 to June 2024,active screening of rectal swab CRE was conducted on ICU patients in 10 hospitals.ICU patients who underwent ac-tive screening from July 2023 to June 2024 were selected as the study group,while those who did not undergo active screening from July 2022 to June 2023 were selected as the control group.Difference in CRE detection rates between the two groups of patients was compared.Results A total of 7 803 ICU patients were included in the study group,744 CRE strains were detected,with a detection rate of 9.53％,out of which 304 CRE strains were detected through routine detection(detection rate 3.90％),3 707 patients underwent active screen,440 CRE strains were detected(detection rate 11.87％).7 561 ICU patients were included in the control group,out of which 250 CRE strains were detected through routine detection,with a detection rate of 3.31％.There was a statistically significant difference in the overall detection rate of CRE between two groups of patients(x2=246.18,P＜0.001).In the study group,CRE detection rate of active screening(11.87％)was higher than that of routine detection(3.90％),with statistically significant difference(x2=264.26,P＜0.001).A total of 17 CRE strains were detected from the study group.The proportions of Klebsiella pneumoniae(80.92％vs 73.41％)and Serratia marcescens(2.30％vs0.23％)in the routine detection group were both higher than in the active screening group,while the proportion of Escherichia coli in the routine detection group was lower(8.22％vs 19.55％),all with statistically significant differences(all P＜0.05).Conclusion The prevalence of CRE in ICUs is relatively high,with a wide range of bac-terial species.Active screening can improve the detection rate of CRE.

Objective:To analyze the correlation between blood glucose index and peripheral neuropathy in type 2 diabetes patients under continuous blood glucose monitoring.Methods:A total of 110 patients with type 2 diabetes admitted to the Lu′an Hospital Affiliated to Anhui Medical University from November 2022 to January 2024 were retrospectively observed, and the blood glucose indexes of patients were monitored by continuous glucose meter [glucose time in range (TIR), mean blood glucose (MBG), estimated hemoglobin A 1c (eHbA 1c), blood glucose standard deviation (SD), coefficient of variation (CV), largest amplitude of glycemic excursions (LAGE), mean amplitude of glycemic excursions (MAGE), means of daily differences (MODD), etc ]. All patients with type 2 diabetes were grouped according to whether they had peripheral neuropathy or not, and were divided into the developing group and the non-developing group. General data and blood glucose indexes of the two groups were collected and sorted out. Receiver operating characteristic (ROC) curve was used to analyze the value of various blood glucose indicators in predicting peripheral neuropathy in patients with type 2 diabetes. Spearman correlation analysis was also used to evaluate the correlation between blood glucose index and peripheral neuropathy. Results:The disease course, TIR, MBG, eHbA 1c, SD, CV, LAGE, MAGE and MODD of the occurrence group were significantly different from those of the non-occurrence group (all P<0.05). By plotting the ROC curve, It was found that the area under the curve (AUC) of TIR, MBG, eHbA 1c, SD, CV, LAGE, MAGE and MODD predicting peripheral neuropathy in patients with type 2 diabetes were 0.942, 0.840, 0.705, 0.759, 0.819, 0.813, 0.857 and 0.677, respectively. The AUC of the combined prediction was 0.971(95% CI: 0.946-0.997), which was higher than that of the single indicator (all P<0.05). Spearman correlation assessment showed a negative correlation between TIR and peripheral neuropathy ( r=-0.738, P<0.05). MBG, eHbA 1c, SD, CV, LAGE, MAGE and MODD were positively correlated with peripheral neuropathy ( r=0.554, 0.376, 0.452, 0.490, 0.527, 0.625, 0.272, all P<0.05). Conclusions:Based on continuous blood glucose monitoring, the blood glucose index of type 2 diabetes patients is closely related to peripheral neuropathy, and the above blood glucose index can accurately predict peripheral neuropathy, providing a reference for reducing or preventing the occurrence of peripheral neuropathy.

This study was aimed at establishing a method of ultra-fast quantitative PCR for Brucella detection.We used an exogenous recombinant plasmid as the internal reference and targeted the T4SS secretion system,an important Brucella viru-lence factor,to design specific primers and probes.The sensitivity,specificity,and repeatability of this method were evaluated,and a standard curve was constructed.The coincidence rate of detection findings with this method versus quantitative PCR was determined.This method markedly decreased the detection time to only 10 minutes.The standard curve demonstrated a good linear relationship(Y=-3.410 7x+38.357,R2=0.998 5)with a low minimum detection limit of 10 copies/μL.The method exhibited good specificity and did not specifically amplify several common clinical bacteria other than Brucella.The de-tection of three concentrations of positive plasmids yielded coefficients of variation(CVs)of 0.20％to 0.91％,thus demonstra-ting the method's excellent repeatability.Furthermore,140 clinical samples were analyzed concurrently with the fluorescence PCR method,which yielded a 100％compliance rate and consistent results.Our findings indicated that the Brucella ultra-fast quantitative PCR was ultrafast;had high sensitivity,high specificity,and good specificity;and can be used for the clinical de-tection of Brucella and emergency investigation of epidemics.Therefore,this method is valuable for the early diagnosis of Bru-cella.

Aim To study the effect of anti-PD-L1 monoclonal antibody on high-fat diet-induced athero-sclerosis in ApoE-/-mice.Methods Twenty-four ApoE-/-mice were randomly divided into the normal group,high-fat group,and high-fat+anti-PD-L1 mAb group.After 70 days,the blood samples were harves-ted.Blood vessels(aortic root to abdominal aorta)and liver from each groups were stained with Oil Red O.Hematoxylin-eosin staining(HE)was employed to vis-ualize structural changes in liver.Enzyme-linked im-munosorbent assay(ELISA)was applied to detect the serum levels of total cholesterol(CHO),triglyceride(TG),high-density lipoprotein(HDL-c),low-density lipoprotein(LDL-c)and inflammatory factors(IFN-γ,TNF-α,IL-1 β).Flow cytometry was used to detect the proportion of lymphocytes(CD4 and CD8).RT-PCR was utilized to assess the expressions of IFN-γ,TNF-α,IL-1 β,CD4 and CD8 in liver.Results Compared with the high-fat group,the treatment with anti-PD-L1 monoclonal antibody promoted vascular wall and liver lipid accumulation,and also up-regulated serum and liver content of cholesterol(CHO),triglyceride(TG)and high-density lipoprotein(HDL-c).Treatment with anti-PD-L1 monoclonal antibody up-regulated the con-tent of alanine aminotransferase(GPT)and aspartate aminotransferase(GOT)in serum and liver,but not al-kaline phosphatase(AKP).ELISA test indicated that treatment with anti-PD-L1 monoclonal antibody stimu-lated the serum level of IFN-γ,TNF-α and IL-1 β.Fur-thermore,the mRNA level of IFN-γ,TNF-α and IL-1 βin liver was also up-regulated after treatment with anti-PD-L1 monoclonal antibody.With flow cytometry,we observed that treatment with anti-PD-L1 monoclonal antibody promoted hepatic CD8+T and CD8+IFN-γ+T cell activation,but had no effect on CD4+IFN-γ+T cell activation under high-fat feeding conditions.Con-clusions Anti-PD-L1 monoclonal antibody adminis-tered under high-fat feeding conditions can damage liv-er function and aggravate atherosclerosis by activating liver CD8+IFN-γ+T cells.

AIM:To investigate the mechanism by which interleukin-13(IL-13)influences vascular smooth muscle cell(VSMC)phenotypic transformation and subsequently contributes to vascular intimal hyperplasia in rats.METHODS:A total of 32 male SD rats,aged 5～7 weeks and weighing 330～360 g,were randomly divided into 4 groups(n=8 per group):normal(Nor)group,normal treatment(Nor+IL-13 neutralizing antibody,Nor+IL-13Nab)group,inju-ry(Inj)group,and injruy treatment(Inj+IL-13Nab)group.A 2F balloon catheter was used to induce mechanical injury in the left common carotid artery of SD rats to establish a vascular intimal hyperplasia model.Hematoxylin-eosin staining was performed to observe vascular structural changes.Enzyme-linked immunosorbent assay(ELISA)kits were used to measure IL-13 and transforming growth factor-β1(TGF-β1)levels.Human aortic smooth muscle cells(HA-SMCs)were cultured in vitro.Flow cytometry was conducted to assess peripheral blood CD4+IL-13+T cell content.Real-time quantita-tive PCR(RT-qPCR)was employed to evaluate gene expression levels of α-smooth muscle actin,osteopontin,calponin,collagen type Ⅰ/Ⅲ,proliferating cell nuclear antigen and Ki-67 antigen.Transwell and scratch wound assays were per-formed to assess cell migration.RESULTS:Compared with the model group,administration of IL-13Nab significantly in-hibited vascular intimal hyperplasia induced by mechanical vascular injury by antagonizing high plasma IL-13 levels(P<0.01).Immunofluorescence and mRNA analysis showed that neutralizing high plasma IL-13 suppressed collagen accumu-lation(P<0.01)and VSMC phenotypic transformation(P<0.01)in the injured vessels but did not inhibit peripheral blood CD4+IL-13+T cell activation.Incubation of HA-SMCs with recombinant human IL-13(rhIL-13)promoted cell pro-liferation and migration(P<0.01)as well as phenotypic transformation(P<0.01).Additional evidence suggested that rhIL-13-induced HA-SMC phenotypic transformation was associated with the regulation of TGF-β1 secretion by HA-SMCs.CONCLUSION:Interleukin-13 promotes vascular intimal hyperplasia by regulating VSMC phenotypic transformation through TGF-β1 secretion in rat models.

Objective: To explore the relationship of physical exercise behavior with mobile phone addiction and mental health of college students, so as to provide evidence for interventions to improve mobile phone addiction and mental health of college students. Methods: From October 8 to December 20 in 2024, 896 college students from 4 colleges in Beijing were selected using a combination of convenience sampling and stratified random cluster sampling method. Physical Activity Rating Scale (PARS-3), Mobile Phone Addiction Tendency Scale (MPATS), Adolescence Mental Health Diathesis Questionnaire (AMHDQ) and Symptom Checklist 90 (SCL-90) were used. The correlation of mobile phone addiction and mental health on physical exercise behavior of college students were analyzed by multivariable Logistic regression and linear regression. Results: Among the surveyed college students, 504 (56.25%) students had low exercise, 262 (29.24%) had moderate exercise, 130 (14.51%) had high exercise, and 392 (43.75%) had sufficient exercise. The total score of PARS-3 was 18.00 ( 15.00 , 33.00) points. Logistic regression analysis showed that the total score of MPATS ( OR=1.022, 95%CI =1.008-1.036), the total score of SCL-90 ( OR=1.010, 95%CI = 1.005 -1.015), the total AMHDQ score ( OR=0.995, 95%CI =0.992-0.998) were significantly associated with insufficient exercise among college students ( P <0.05). Linear regression analysis showed that the scores of MPATS, AMHDQS and SCL-90 were significantly correlated with physical exercise behavior ( B=-0.20, 0.04, -0.07, P <0.05). Conclusion The physical exercise behavior of college students is related to mobile phone addiction and mental health.