BACKGROUND: Non-invasive computed tomography angiography (CTA)-based fractional flow reserve (CT-FFR) could become a gatekeeper to invasive coronary angiography. Deep learning (DL)-based CT-FFR has shown promise when compared to invasive FFR. To evaluate the performance of a DL-based CT-FFR technique, DeepVessel FFR (DVFFR). METHODS: This retrospective study was designed for iScheMia Assessment based on a Retrospective, single-center Trial of CT-FFR (SMART). Patients suspected of stable coronary artery disease (CAD) and undergoing both CTA and invasive FFR examinations were consecutively selected from the Beijing Anzhen Hospital between January 1, 2016 to December 30, 2018. FFR obtained during invasive coronary angiography was used as the reference standard. DVFFR was calculated blindly using a DL-based CT-FFR approach that utilized the complete tree structure of the coronary arteries. RESULTS: Three hundred and thirty nine patients (60.5 ±10.0 years and 209 men) and 414 vessels with direct invasive FFR were included in the analysis. At per-vessel level, sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of DVFFR were 94.7%, 88.6%, 90.8%, 82.7%, and 96.7%, respectively. The area under the receiver operating characteristics curve (AUC) was 0.95 for DVFFR and 0.56 for CTA-based assessment with a significant difference (P < 0.0001). At patient level, sensitivity, specificity, accuracy, PPV and NPV of DVFFR were 93.8%, 88.0%, 90.3%, 83.0%, and 95.8%, respectively. The computation for DVFFR was fast with the average time of 22.5 ± 1.9 s. CONCLUSIONS The results demonstrate that DVFFR was able to evaluate lesion hemodynamic significance accurately and effectively with improved diagnostic performance over CTA alone. Coronary artery disease (CAD) is a critical disease in which coronary artery luminal narrowing may result in myocardial ischemia. Early and effective assessment of myocardial ischemia is essential for optimal treatment planning so as to improve the quality of life and reduce medical costs.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Objective:To detect the serum levels of 25(OH)D,miR-125b-5p,hypoxia-inducible factor-1α(HIF-1α)and vascular endothelial growth factor A(VEGFA)in patients with multiple myeloma(MM),and explore the role of miR-125b-5p/HIF-1α pathway in the involvement of vitamin D deficiency in the pathogenesis of MM.Methods:Fifty three newly diagnosed/relapsed MM patients admitted to the department of hematology of our hospital from October 2021 to December 2023 were included.Meanwhile,25 healthy individuals matched in gender and age from our hospital's Health Management Center were selected as controls.The serum level of 25(OH)D was monitored by mass spectrometry,the serum level of miR-125b-5p was detected by real-time fluorescence quantitative PCR,and serum levels of HIF-1α and VEGFA were measured by enzyme-linked immunosorbent assay.The levels of 25(OH)D,miR-125b-5p,HIF-1α,and VEGFA were compared between the two groups.According to the level of 25(OH)D,the MM patients were divided into vitamin D deficiency group(＜20 ng/ml)and vitamin D non-deficiency group(≥ 20 ng/ml),and the levels of miR-125b-5p,HIF-1α,and VEGFA were compared between the two groups.The correlations between 25(OH)D,miR-125b-5p,HIF-1α and VEGFA were analyzed.The receiver operating characteristic(ROC)curve analysis was used to determine the diagnostic value of25(OH)D combined with miR-125b-5p for newly diagnosed MM.Results:The level of 25(OH)D in MM patients was significantly lower than that in control group(P＜0.01).There was no significant difference in 25(OH)D level between newly diagnosed and relapsed MM patients(P＞0.05).Compared with the control group,the level of miR-125b-5p was significantly reduced in MM patients(P＜0.01),while the levels of HIF-1α and VEGFA were significantly increased(both P＜0.001).In MM patients,the miR-125b-5p level in the vitamin D deficiency group was significantly decreased than that in the non-deficiency group(P＜0.01),while the levels of HIF-1 α and VEGFA were significantly increased(both P＜0.05).In MM patients,25(OH)D was positively correlated with miR-125b-5p,while negatively correlated with HIF-1α and VEGFA(both P＜0.05).Moreover,miR-125b-5p was negatively correlated with HIF-1α and VEGFA(both P＜0.05).The area under the curve(AUC)for diagnosing MM with 25(OH)D,miR-125b-5p,and their combination were 0.699,0.751,and 0.791,respectively.Conclusion:The incidence of vitamin D deficiency is high in MM patients.Vitamin D deficiency may promote angiogenesis and participate in the occurrence and development of MM by downregulating miR-125b-5p and upregulating HIF-1α and VEGFA expression.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Objective:To detect the serum levels of 25(OH)D,miR-125b-5p,hypoxia-inducible factor-1α(HIF-1α)and vascular endothelial growth factor A(VEGFA)in patients with multiple myeloma(MM),and explore the role of miR-125b-5p/HIF-1α pathway in the involvement of vitamin D deficiency in the pathogenesis of MM.Methods:Fifty three newly diagnosed/relapsed MM patients admitted to the department of hematology of our hospital from October 2021 to December 2023 were included.Meanwhile,25 healthy individuals matched in gender and age from our hospital's Health Management Center were selected as controls.The serum level of 25(OH)D was monitored by mass spectrometry,the serum level of miR-125b-5p was detected by real-time fluorescence quantitative PCR,and serum levels of HIF-1α and VEGFA were measured by enzyme-linked immunosorbent assay.The levels of 25(OH)D,miR-125b-5p,HIF-1α,and VEGFA were compared between the two groups.According to the level of 25(OH)D,the MM patients were divided into vitamin D deficiency group(＜20 ng/ml)and vitamin D non-deficiency group(≥ 20 ng/ml),and the levels of miR-125b-5p,HIF-1α,and VEGFA were compared between the two groups.The correlations between 25(OH)D,miR-125b-5p,HIF-1α and VEGFA were analyzed.The receiver operating characteristic(ROC)curve analysis was used to determine the diagnostic value of25(OH)D combined with miR-125b-5p for newly diagnosed MM.Results:The level of 25(OH)D in MM patients was significantly lower than that in control group(P＜0.01).There was no significant difference in 25(OH)D level between newly diagnosed and relapsed MM patients(P＞0.05).Compared with the control group,the level of miR-125b-5p was significantly reduced in MM patients(P＜0.01),while the levels of HIF-1α and VEGFA were significantly increased(both P＜0.001).In MM patients,the miR-125b-5p level in the vitamin D deficiency group was significantly decreased than that in the non-deficiency group(P＜0.01),while the levels of HIF-1 α and VEGFA were significantly increased(both P＜0.05).In MM patients,25(OH)D was positively correlated with miR-125b-5p,while negatively correlated with HIF-1α and VEGFA(both P＜0.05).Moreover,miR-125b-5p was negatively correlated with HIF-1α and VEGFA(both P＜0.05).The area under the curve(AUC)for diagnosing MM with 25(OH)D,miR-125b-5p,and their combination were 0.699,0.751,and 0.791,respectively.Conclusion:The incidence of vitamin D deficiency is high in MM patients.Vitamin D deficiency may promote angiogenesis and participate in the occurrence and development of MM by downregulating miR-125b-5p and upregulating HIF-1α and VEGFA expression.

Objective To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine(MDMA)and its metabolite 4,5-methylene dioxy amphetamine(MDA)in rats af-ter single and continuous administration of MDMA,providing reference data for the forensic identifica-tion of MDMA.Methods A total of 24 rats in the single administration group were randomly divided into 5,10 and 20 mg/kg experimental groups and the control group,with 6 rats in each group.The ex-perimental group was given intraperitoneal injection of MDMA,and the control group was given intraperi-toneal injection of the same volume of normal saline as the experimental group.The amount of 0.5 mL blood was collected from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.In the continuous administration group,24 rats were randomly divided into the experi-mental group(18 rats)and the control group(6 rats).The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5,7,9,11,13,15,17 mg/kg per day,respectively,while the control group was given the same volume of normal saline as the experimental group by in-traperitoneal injection.On the eighth day,the experimental rats were randomly divided into 5,10 and 20 mg/kg dose groups,with 6 rats in each group.MDMA was injected intraperitoneally,and the con-trol group was injected intraperitoneally with the same volume of normal saline as the experimental group.On the eighth day,0.5 mL of blood was taken from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels,and statistical software was employed for data analysis.Results In the single-administration group,peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration,respectively,with the largest detection time limit of 12 h.In the continuous administration group,peak concentrations were reached at 30 min and 1.5 h af-ter administration,respectively,with the largest detection time limit of 10 h.Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows:T=10.362C-1.183,R2=0.974 6;T=7.397 3C-0.694,R2=0.961 5(T:injection time;C:concentration ratio of MDMA to MDA in plasma).Conclusions The toxicokinetic data of MDMA and its metabolite MDA in rats,obtained through single and continuous administration,including peak concentration,peak time,detection time limit,and the relationship between concentration ratio and administration time,provide a theoretical and data foundation for relevant forensic identification.

Objective To design a medical order pre-evaluation tool for perioperative prophylactic application of antibiotics,and to improve the efficiency of antibiotics management in hospitals during the perioperative period.Methods Using the open-source software R as the platform,a web application was built with tidy verse and shiny package based on related documents and guidelines.The discharge records of Affiliated Hospital of North Sichuan Medical College from April 1,2021,to December 31,2022,were retrospectively reviewed using the constructed pre-evaluation tool and compared with previous manual evaluation results using McNemar's Chi-squared test.Results This medical order pre-evaluation tool can quickly complete perioperative antibiotics order sampling,batch pre-evaluation,result statistics,visualization,and result output,and flexibly adjust the evaluation rules according to actual needs.The pre-evaluation tool is more efficient,with a review speed of 13.46 ms per medical record.Among the 2 642 discharge medical records of manual review,there was no significant difference between systematic pre-evaluation and manual evaluation results(ratio of prophylactic use:76.85%vs.78.21%)in terms of the type of use(preventive or curative)(P= 0.078).Among the 1 857 discharge records judged to be prophylactic for both manual and systematic reviews,the difference in unreasonable detection rate(39.90%vs.30.32%)was statistically significant(P＜0.001).Among the 63 typical ludicrous medical records confirmed by the review of clinical pharmacists with senior professional titles,60 were judged and limited by the pre-evaluation tool,and the detection rate of typical unreasonable was 95.24%.Conclusions The pre-evaluation tool based on R in this study can improve the efficiency of perioperative antibacterial drug evaluation.The evaluation conclusions and statistical results are reliable and are worthy of further development and application.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

Objective:To study the current status of longitudinal extrauterine growth restriction (EUGR) in extremely preterm infants (EPIs) and to develop a prediction model based on clinical data from multiple NICUs.Methods:From January 2017 to December 2018, EPIs admitted to 32 NICUs in North China were retrospectively studied. Their general conditions, nutritional support, complications during hospitalization and weight changes were reviewed. Weight loss between birth and discharge > 1SD was defined as longitudinal EUGR. The EPIs were assigned into longitudinal EUGR group and non-EUGR group and their nutritional support and weight changes were compared. The EPIs were randomly assigned into the training dataset and the validation dataset with a ratio of 7∶3. Univariate Cox regression analysis and multiple regression analysis were used in the training dataset to select the independent predictive factors. The best-fitting Nomogram model predicting longitudinal EUGR was established based on Akaike Information Criterion. The model was evaluated for discrimination efficacy, calibration and clinical decision curve analysis.Results:A total of 436 EPIs were included in this study, with a mean gestational age of (26.9±0.9) weeks and a birth weight of (989±171) g. The incidence of longitudinal EUGR was 82.3%(359/436). Seven variables (birth weight Z-score, weight loss, weight growth velocity, the proportion of breast milk ≥75% within 3 d before discharge, invasive mechanical ventilation ≥7 d, maternal antenatal corticosteroids use and bronchopulmonary dysplasia) were selected to establish the prediction model. The area under the receiver operating characteristic curve of the training dataset and the validation dataset were 0.870 (95% CI 0.820-0.920) and 0.879 (95% CI 0.815-0.942), suggesting good discrimination efficacy. The calibration curve indicated a good fit of the model ( P>0.05). The decision curve analysis showed positive net benefits at all thresholds. Conclusions:Currently, EPIs have a high incidence of longitudinal EUGR. The prediction model is helpful for early identification and intervention for EPIs with higher risks of longitudinal EUGR. It is necessary to expand the sample size and conduct prospective studies to optimize and validate the prediction model in the future.

ObjectiveTo explore whether miR-375 regulates the malignant characteristics of osteosarcoma (OS) by influencing the expression of MMP13. MethodsPlasmid DNAs and miRNAs were transfected into OS cells and HEK293 cells using Lipofectamine 3000 reagent. Real-time quantitative polymerase chain reaction was performed to measure the expression of miR-375 and MMP13 in OS patients and OS cells. Western blot was performed to analyze the MMP13 protein in the patients with OS and OS cells. The targeting relationship between miR-375 and MMP13 was analyzed by luciferase assay. Migration and invasion were analysed by heal wound and transwell assays, respectively. ResultsmiR-375 expression in OS tissues was lower than that in normal tissues. The expression of MMP13 was upregulated in OS tissues. MMP13 expression was negatively correlated withmiR-375 expression in patients with OS. Migration and invasion were significantly inhibited in OS cells with the miR-375 mimic compared with OS cells with the miRNA control. MMP13 partially reversed the inhibition of migration and invasion induced by miR-375 in the OS cells. ConclusionmiR-375 attenuates migration and invasion by downregulating the expression of MMP13 in OS cells.