Objective To evaluate the radiation impact of a self-developed digital miniature CT on the human body and the environment under simulated scanning conditions, and verify its safety and regulatory compliance. Methods Under typical head scanning conditions with the digital miniature CT (70 kV/10 mA), the equivalent doses received at the body surface sites corresponding to the thyroid, breast, stomach, liver, kidney, and gonads of the phantom were measured without protection and with 0.5 mmPb equivalent protection using LiF (Mg, Cu, P) thermoluminescent dosimeters. The ambient dose equivalent rates at the bed level inside the CT room at different directions and distances from the scanning center were measured using a model AT1121 X/γ dosimeter. The equivalent doses of organs on both sides of the phantom and the ambient equivalent dose rates on the left and right sides of the longitudinal axis of the bed in the CT room were compared. The Mann-Whitney test was used at a significance level of P < 0.05. Results During a single scan of the head with the digital miniature CT, the equivalent doses at the body surface sites corresponding to the thyroid, breast, stomach, liver, kidney, and gonads without protection were 1.04, 0.95, 0.55, 0.57, 0.40, and 0.12 mSv, respectively, which were only 0.84% to 8.24% of the doses inside the irradiation field. With 0.5 mm Pb equivalent protection, the equivalent dose of the thyroid decreased from 8.24 mSv to 3.27 mSv with a reduction of 60.3%, and the doses of the other organs were reduced to 1.5-11.5 μSv with the maximum reduction of 14 times. In the longitudinal axis direction of the CT bed, the ambient dose equivalent rate at a distance of 2 m from the scanning center was reduced to 0.066 mSv/h, which was only 9.6% of the ambient equivalent dose rate at a distance of 50 cm from the scanning center. Conclusion The digital miniature CT has advantages in ensuring patient safety, optimizing imaging quality, and promoting technological development, demonstrating promising application potential. However, the radiation protection of personal and CT room should not be ignored.

Background::Total human immunodeficiency virus (HIV) DNA and integrated HIV DNA are widely used markers of HIV persistence. Droplet digital polymerase chain reaction (ddPCR) can be used for absolute quantification without needing a standard curve. Here, we developed duplex ddPCR assays to detect and quantify total HIV DNA and integrated HIV DNA.Methods::The limit of detection, dynamic ranges, sensitivity, and reproducibility were evaluated by plasmid constructs containing both the HIV long terminal repeat (LTR) and human CD3 gene (for total HIV DNA) and ACH-2 cells (for integrated HIV DNA). Forty-two cases on stable suppressive antiretroviral therapy (ART) were assayed in total HIV DNA and integrated HIV DNA. Correlation coefficient analysis was performed on the data related to DNA copies and cluster of differentiation 4 positive (CD4 +) T-cell counts, CD8 + T-cell counts and CD4/CD8 T-cell ratio, respectively. The assay linear dynamic range and lower limit of detection (LLOD) were also assessed. Results::The assay could detect the presence of HIV-1 copies 100% at concentrations of 6.3 copies/reaction, and the estimated LLOD of the ddPCR assay was 4.4 HIV DNA copies/reaction (95% confidence intervals [CI]: 3.6-6.5 copies/reaction) with linearity over a 5-log 10-unit range in total HIV DNA assay. For the integrated HIV DNA assay, the LLOD was 8.0 copies/reaction (95% CI: 5.8-16.6 copies/reaction) with linearity over a 3-log 10-unit range. Total HIV DNA in CD4 + T cells was positively associated with integrated HIV DNA ( r = 0.76, P <0.0001). Meanwhile, both total HIV DNA and integrated HIV DNA in CD4 + T cells were inversely correlated with the ratio of CD4/CD8 but positively correlated with the CD8 + T-cell counts. Conclusions::This ddPCR assay can quantify total HIV DNA and integrated HIV DNA efficiently with robustness and sensitivity. It can be readily adapted for measuring HIV DNA with non-B clades, and it could be beneficial for testing in clinical trials.

Objective To construct an artificial intelligence assisted diagnosis model based on deep learning for dynamically recognizing gastric lesions and their locations under gastroscopy in real time,and to evaluate its ability to detect and recognize gastric lesions and their locations.Methods The gastroscopy videos of 104 patients in our hospital was retrospectively analyzed,and the video frames were manually annotated.The annotated picture frames of lesion category were divided into the training set and the validation set according to the ratio of 8∶2,and the annotated picture frames of location category were divided into the training set and the validation set according to the patient sources at the ratio of 8∶2.These sets were utilized for training and validating the respective models.YoloV4 model was used for the training of lesion recognition,and ResNet152 model was used for the training of location recognition.The accuracy,sensitivity,specificity,positive predictive value,negative predictive value and location recognition accuracy of the auxiliary diagnostic model were evaluated.Results A total of 68 351 image frames were annotated,with 54 872 frames used as the training set,including 41 692 frames for lesion categories and 13 180 frames for location categories.The validation set consisted of 13 479 frames,comprising 10 422 frames for lesion categories and 3 057 frames for location categories.The lesion recognition model achieved an overall accuracy of 98.8%,with a sensitivity of 96.6%,specificity of 99.3%,positive predictive value of 96.3%,and negative predictive value of 99.3% in validation set.Meanwhile,the location recognition model demonstrated an top-5 accuracy of 87.1% .Conclusion The artificial intelligence assisted diagnosis model based on deep learning for real-time dynamic recognition of gastric lesions and their locations under gastroscopy has good ability in lesion detection and location recognition,and has great clinical application prospects.

Objective This study aimed to explore the diagnostic concordance of fractional flow reserve(FFR)and quantitative flow ratio(QFR)and the characteristics affecting this concordance.Methods Patients with non-acute myocardial infarction admitted to the Department of Cardiology,Peking University Third Hospital between January 2019 and December 2021 were enrolled.The patients were divided into four groups:FFR+/QFR+and FFR-/QFR-,FFR+/QFR-and FFR-/QFR+with FFR or QFR≤0.80 as positive and＞0.80 as negative.Using FFR as the gold standard,the diagnostic value of QFR was analyzed,and differences in clinical features and pathological characteristics among the groups were compared.Results A total of 236 patients were included.The mean age was(64.48±9.63)years,and 67.8％were male.All patients had 30％-70％coronary stenosis.The consistency rate of QFR and FFR was 78.0％(n=184),and the Person correlation coefficient was 0.557(P＜0.001).Among FFR+patients,the minimum lumen diameter was larger[(1.56±0.34)mm vs.(1.39±0.31)mm,P=0.019],lesion length was shorter[(21.37±11.73)mm vs.(36.86±18.09)mm,P＜0.001],and coronary angiography-based index of microcirculartory resistance(AMR)was higher[(277.50±28.87)mmHg·s/m vs.(178.02±49.13)mmHg·s/m,P＜0.001]in the disconcordance group.Multivariate regression analysis suggested that AMR[OR 0.93,95％CI 0.88-0.99,P=0.030]and lesion length[OR 1.27,95％CI 1.01-1.60,P=0.045]were independent predictors of disconcordance.In the FFR-group,the lesion length was longer[(33.08±16.05)mm vs.(21.40±13.36)mm,P=0.020],and AMR[(169.66±24.01)mmHg·s/m vs.(265.95±44.78)mmHg·s/m,P＜0.001]and low-density lipoprotein-C[1.57(1.10,1.97)mmol/L vs.2.15(1.79,2.74)mmol/L,P=0.031]were lower in the disconcordance group.No statistically significant variables were identified by multivariate regression.Conclusions QFR had high diagnostic value compared with FFR.In the FFR+group,AMR and lesion length may have affected the diagnostic consistency of QFR and FFR.The study provided more evidence for the clinical application of QFR.

Objective To investigate the safety and efficacy of novel bioabsorbable vascular scaffold(BVS)in the treatment of patients with complex coronary artery disease.Methods This was a retrospective,matched,single-center observational study.45 patients with coronary atherosclerotic cardiopathy received BVS treatment in the cardiovascular medicine department Department of the Affiliated Hospital of Guangdong Medical University from June 2020 to June 2021(BVS),and 45 patients treated with drug-eluting stents(DES)group were selected according to matching study requirements during the same period.Baseline,surgical,and follow-up data were compared between the two groups to evaluate safety and efficacy.The main measures of safety were:surgical time,intraoperative adverse events,etc.,and the end point of efficacy was target lesion failure(TLF),including cardiac death,target vessel myocardial infarction,and ischa-driven target lesion revascularization.Results A total of 90 patients were enrolled in this study,all of whom were followed up for at least 3 years.There were 20 cases of bifurcation lesions and 25 cases of diffuse long lesions in the two groups,and 50 cases of imaging were reviewed among the 90 patients.The proportion of stable coronary heart disease,history of diabetes,history of hypertension,history of smoking,pre-dilated balloon pressure and postoperative diastolic blood pressure in BVS group was higher than that in DES group,and the proportion of family history was lower than that in DES group(all P＜0.05).There were no statistically significant differences in the rates of cardiac death,target vessel myocardial infarction,and ischemia-driven revascularization of target lesions between the two groups(all P＞0.05).Binary Logistic regression model analysis showed that the diameter stenosis ratio of target lesions was an independent risk factor for intrastent restenosis(OR 2.786,95％CI 1.096-7.081,P=0.031).Conclusions Compared with traditional DES,BVS implantation has consistent safety and efficacy in the treatment of complex coronary artery disease within 3 years.The diameter stenosis ratio of target lesions was an independent risk factor for intrastent restenosis.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective:To prepare mesenchymal stem cells with antioxidant capacity (AO-MSC ) from human umbilical cords and evaluate its cell biological properties.Methods:In control group,mesenchymal stem cells (MSC) were isolated by digesting human umbilical cord Wharton's Jelly tissues with 0.2％ collagenase Ⅱ,and the released cells were collected and cultured in an animal serum-free culture medium.In AO-MSC group,incompletely collagenase Ⅱ-digested tissue debris were allowed to adhere to flusk flat bottoms and the AO-MSC was harvested by adherent culture. The conventional digestion and culture method was used as control.MSC colony forming ability was evaluated by fibroblast colony forming assay (CFU-F).MSC proliferative capacity was evaluated by CCK-8 assay.The MSC surface markers were detected by using flow cytometry and immunofluorescence staining.The adipogenic and osteogenic capacity of MSC was evaluated by multi-differentiation in vitro,and the mRNA expression of genes that control adipogenic and osteogenic differentiation was detected by real-time fluorescence quantitative PCR (RT-qPCR );Moreover,the mRNA expression of antioxidant substances such as SOD-1,GSH,GAT,and NQO1 in MSC was also evaluated by RT-qPCR.Results:The AO-MSC isolated by this strategy reached a confluence of 80％-90％ at around 18 days and grew in a swirling pattern.Flow cytometry and immunofluorescence staining assays showed that CD73,CD29,CD105,CD90 were highly expressed and CD31,CD45,HLA-DR were scarcely expressed in AO-MSC.AO-MSC exhibited stronger self-renewal and differentiation ability compared to MSC.However,the in vitro adipogenic-osteogenic capacity of MSC in the control group was stronger than that of AO-MSC.RT-qPCR assay showed that AO-MSC expressed higher mRNA levels of antioxidant substances compared to MSC.Conclusion:Human AO-MSC is successfully prepared from human umbilical cord without animal serum.

Two pediatric heart failure patients were treated with pulmonary artery banding(PAB)at Fuwai Hospital,from December 2021 to January 2022.In the first case,an 8-month-old patient presented with left ventricular non-compaction cardiomyopathy(LVNC),left ventricular systolic dysfunction,ventricular septal defect,and atrial septal defect.The second case was a 4-month-old patient with LVNC,left ventricular systolic dysfunction,and coarctation of the aorta.After PAB,the left ventricular function and shape of both patients were significantly improved,without serious surgery-related complications.In these individual cases of pediatric heart failure,pulmonary artery banding exhibited a more satisfactory efficacy and safety compared to pharmacological treatment,especially for those with unsatisfactory medication results.Future clinical data are needed to promote the rational and broader application of this therapeutic option for indicated patients.

Background: Triglyceride glucose (TyG) and TyG-body mass index (TyG-BMI) are reliable surrogate indices of insulin resistance and used for risk stratification and outcome prediction in patients with atherosclerotic cardiovascular disease (ASCVD). Here, we inserted estimated average glucose (eAG) into the TyG (TyAG) and TyG-BMI (TyAG-BMI) as derived parameters and explored their clinical significance in cardiovascular risk prediction. Methods: This was a population-based cohort study of 9,944 Chinese patients with ASCVD. The baseline admission fasting glucose and A1C-derived eAG values were recorded. Cardiovascular events (CVEs) that occurred during an average of 38.5 months of follow-up were recorded. We stratified the patients into four groups by quartiles of the parameters. Baseline data and outcomes were analyzed. Results: Distribution of the TyAG and TyAG-BMI indices shifted slightly toward higher values (the right side) compared with TyG and TyG-BMI, respectively. The baseline levels of cardiovascular risk factors and coronary severity increased with quartile of TyG, TyAG, TyG-BMI, and TyAG-BMI (all P<0.001). The multivariate-adjusted hazard ratios for CVEs when the highest and lowest quartiles were compared from low to high were 1.02 (95% confidence interval [CI], 0.77 to 1.36; TyG), 1.29 (95% CI, 0.97 to 1.73; TyAG), 1.59 (95% CI, 1.01 to 2.58; TyG-BMI), and 1.91 (95% CI, 1.16 to 3.15; TyAG-BMI). The latter two showed statistical significance. Conclusion This study suggests that TyAG and TyAG-BMI exhibit more information than TyG and TyG-BMI in disease progression among patients with ASCVD. The TyAG-BMI index provided better predictive performance for CVEs than other parameters.

Objective:To investigate the prognostic factors for liver transplantation for hepatocellular carcinoma beyond UCSF criteria but without macrovascular invasion.Methods:A retrospective analysis was performed for the clinical data of the hepatocellular carcinoma patients without macrovascular invasion beyond UCSF criteria who underwent liver transplantation at our center from Jan 2018 to Jun 2023. The receiver operating characteristic curve analysis was performed to assess the predictive power of potential prognosis factors.Results:With this criteria, the 1-, 3-year overall survival rates were 94.1% and 75.0%, respectively, and the 1-, 3-year tumor free survival rates were 82.4% and 38.1%, respectively. The maximum tumor size, number of tumors, AFP, PIVKA-Ⅱ before transplantation, and whether undergo pretransplant down-stage therapy were significant prognostic factors ( P<0.05). Combining the above prognostic factors to construct the receiver operating characteristic curve yielded an area under the curve of 0.967, with a sensitivity and specificity of 0.932, 0.952, respectively. Further, the differentiation, MVI and Ki-67 were significant prognostic factors ( P<0.05). Combining pathological factors to construct the receiver operating characteristic curve yielded an area under the curve of 0.927, with a sensitivity and specificity of 0.769, 1, respectively. Conclusion:The maximum tumor diameter, number of tumors, AFP, PIVKA-Ⅱ before transplantation, and pretransplant down-stage therapy and tumor differentiation, MVI and Ki-67 are all prognostic factors of liver transplantation for hepatocellular carcinoma without macrovascular invasion beyond UCSF criteria.