Objective:To investigate the roles of simulated participants in the facilitation of medical scenarios simulation-based course and to provide a reference for the standardized construction of medical scenarios simulation-based course.Methods:Thirty scenario simulation-based teaching sessions on perioperative crisis events conducted during the 2022-2023 academic year were observed on-site. The performance of simulated participants in facilitating case execution and the skills used in facilitation were observed and recorded. At the end of the course, surveys regarding facilitation were administered to students, simulated participants, and instructors for analysis.Results:In the facilitation of 30 scenario simulation-based teaching sessions on perioperative crisis events, the roles of simulated participants included surgeon, anesthesia nurse, circuit nurse, and standardized patient. Two simulated participants accounted for 80.00% and three participants for 20.00% of the total sessions. The simulated participants performed excellently in helping the learners quickly integrate into the scenario and controlling the direction of the case, with an excellence rate of 90.00%-100.00%. However, they had some variations in driving the progress of the case and responding to unexpected situations, with an excellence rate of 50.00%-60.00%. The facilitation skills used by simulated participants included hinting, prompting, and instructing. The performance of facilitation was closely related to the use of skills by the simulated participants. Simulated participants with proficient skill usage significantly enhanced teaching effectiveness. Post-session surveys revealed that learners generally perceived simulated participants as having a positive impact on facilitation, and both simulated participants and instructors emphasized the need for strengthened communication prior to simulation-based teaching.Conclusions:The simulated participants played important roles in guiding learners, advancing case progression, and achieving teaching objectives. Instructors should not only consider the scripting of simulated participants during lesson planning but also prioritize their training and communication during course implementation.

Objective:To investigate the impact of different etiologies on the spatial distribution pattern of infarcts and the mapping pattern of focal symptoms in acute ischemic stroke (AIS) using a population-based standardized spatial analysis of MRI.Methods:This was a cross-sectional study. Clinical [age, sex distribution, admission National Institutes of Health Stroke Scale (NIHSS) score and 90-day modified Rankin Scale (mRS) score at discharge, etc.] and imaging data of 2 610 patients with AIS attending 9 Medical Centers from January 2015 to December 2021 were retrospectively analyzed. All patients were categorized into 1 718 cases of large artery atherosclerosis (LAA) type, 335 cases of cardioembolism (CE) type, and 557 cases of small artery occlusion (SAO) type according to TOAST typing. All patients underwent diffusion-weighted imaging, and the detected infarct lesions were segmented and aligned to the standardized space using artificial intelligence-assisted methods, and the spatial distribution frequency heatmaps of lesion locations in patients with different TOAST subtypes were plotted and compared with each other by χ2 test. Lesion-symptom image brain maps with different clinical symptoms were further plotted, and differences of lesion-symptom image relationships among different TOAST subtypes were observed and compared with each other by interaction effect. Results:In all patients, the favored sites of infarct lesions were the bilateral middle cerebral artery region in the anterior circulation and the occipital and brainstem regions in the posterior circulation. Compared with the LAA type, the CE type lesions were more likely to occur in the anterior cerebral artery region, the occipital lobe, and the cerebellum posterior, while the SAO type lesions were more likely to occur in the perforator artery supply area. The lesion-symptom mapping results showed that AIS patients with infarct lesions in the frontoparieto-temporal region in the presence of a left middle cerebral artery supply had higher admission NIHSS scores and higher discharge 90-day mRS scores for the LAA type than for the CE type( P<0.05); AIS patients with infarcted lesions in the brainstem region and some cerebellar regions in the presence of vertebrobasilar artery supply had higher admission NIHSS scores and higher discharge 90-day mRS scores for the CE type than for the LAA type( P<0.05). Conclusion:At the population level, brain mapping reveals specific infarct distribution patterns and differences in lesion-symptom mapping patterns of different etiologies AIS patients, providing imaging evidence for the understanding of AIS pathogenetic mechanisms and clinical management.

In order to establish a serological method for the detection of bovine parainfluenza virus type 3(BPIV3),the prokaryotic expression and purification of BPIV3 HN,NP,F,and P proteins were carried out,and the optimal protein-coated antigen was screened,and an indirect ELISA de-tection method was established.The results showed that the four recombinant proteins of BPIV3,rHN,rNP,rF,and rP were expressed,and the checkerboard titration results showed that rHN pro-tein had the highest P/N value as the coating protein,so it was used for the subsequent method es-tablishment.The optimal reaction conditions for indirect ELISA were found to be:the mass con-centration of the antigen coating was 0.5 mg/L,37 ℃ 1.5 h,5％skim milk,overnight blocking at 4 ℃,serum dilution at 1∶50,incubation at 37 ℃ 1 h,secondary antibody dilution at 1∶10 000 and incubation at 37℃ 0.5 h,substrate reaction conditions were 37℃ for 12 min.The results of speci-ficity experiments showed that the established method could specifically identify BPIV3 antibody-positive serum with a sensitivity of 1∶800,and the coefficient of variation in the detection of intra-and inter-assay repeatability was less than 10％,and the overall coincidence rate of the same batch of samples detected with the SVANOVIR kit was 92.22％.This method was used to detect 192 se-rum samples in Hebei Province,and the positive rate of BPIV3 antibody in serum was 66.15％.The indirect ELISA detection method of BP1V3 antibody constructed in this study is suitable for large-scale clinical serological investigations,and provides valuable data support for the research and de-velopment of BPIV3 antigen and antibody detection kits in China.

BACKGROUND:Adolescent lumbar disc herniation is the main cause of low back pain in adolescents. At present,most of them are treated by conservativetreatment. When long-term non-surgical treatment attempts,surgery may be necessary to prevent further injury when the patient's symptoms are notsufficiently relieved or when the patient has symptoms of single nerve paralysis or compression of the cauda equina,it is very important to choose a suitable interbody fusion device for the surgical treatment of the patients.OBJECTIVE:To explore the effects of minimally invasive interbody fusion with different heights on lumbar biomechanics in patients with adolescent lumbar disc herniation.METHODS:CT scans of a 17-year-old male patient with adolescent lumbar disc herniation (L4-5 segment herniation) were collected. After the three-dimensional reconstruction of MIMICS,the interbody fusion device equal to and 3 mm higher than the intervertebral space was selected for analysis,so two expandablemixed material interbody fusion devices were designed and reconstructed. Fusion device L:11 mm high front,9 mm high posterior,9 mm wide,28 mmlong,and fusion device H:14 mm high front,11 mm high posterior,11 mm wide,28 mm long and the lumbar fusion device was modeled. The fusion deviceand lumbar spine model were optimized,inversely modeled,and then imported into ABAQUS,and finally the 3D model of lumbar fusion was obtained.The physiological activities of the human body were simulated,such as lumbar extension,forward bending,right bending,and left bending,to obtain thecorresponding stress contours. The biomechanical characteristics of the L4-5 vertebra under seven different working conditions were observed.RESULTS AND CONCLUSION:(1) The maximum stress of the two kinds of fuses was in the condition of forward bending and backward extension,the stress value of H fuses was (18.27±3.80) Mpa and (15.02±3.24) Mpa;the stress value of L fuses was (9.16±0.05) Mpa and (9.17±1.83) Mpa. The stress values of the end plate of the H-fusion in the extension station were (19.11±4.03) Mpa and (16.32±3.72) Mpa respectively. The stress values of the L-fusion end plate were (9.13±0.01) Mpa and (4.92±1.01) Mpa respectively. (2) The stress of H-type fusing end plate was higher than that of L-type fusing end plate except for L-5 end plate at neutral position (P<0.05). (3) Choosing an interbody fusion device with a height of more than 3 mm in the same intervertebral space has a more stable biomechanics.

BACKGROUND:Adolescent lumbar disc herniation is the main cause of low back pain in adolescents. At present,most of them are treated by conservativetreatment. When long-term non-surgical treatment attempts,surgery may be necessary to prevent further injury when the patient's symptoms are notsufficiently relieved or when the patient has symptoms of single nerve paralysis or compression of the cauda equina,it is very important to choose a suitable interbody fusion device for the surgical treatment of the patients.OBJECTIVE:To explore the effects of minimally invasive interbody fusion with different heights on lumbar biomechanics in patients with adolescent lumbar disc herniation.METHODS:CT scans of a 17-year-old male patient with adolescent lumbar disc herniation (L4-5 segment herniation) were collected. After the three-dimensional reconstruction of MIMICS,the interbody fusion device equal to and 3 mm higher than the intervertebral space was selected for analysis,so two expandablemixed material interbody fusion devices were designed and reconstructed. Fusion device L:11 mm high front,9 mm high posterior,9 mm wide,28 mmlong,and fusion device H:14 mm high front,11 mm high posterior,11 mm wide,28 mm long and the lumbar fusion device was modeled. The fusion deviceand lumbar spine model were optimized,inversely modeled,and then imported into ABAQUS,and finally the 3D model of lumbar fusion was obtained.The physiological activities of the human body were simulated,such as lumbar extension,forward bending,right bending,and left bending,to obtain thecorresponding stress contours. The biomechanical characteristics of the L4-5 vertebra under seven different working conditions were observed.RESULTS AND CONCLUSION:(1) The maximum stress of the two kinds of fuses was in the condition of forward bending and backward extension,the stress value of H fuses was (18.27±3.80) Mpa and (15.02±3.24) Mpa;the stress value of L fuses was (9.16±0.05) Mpa and (9.17±1.83) Mpa. The stress values of the end plate of the H-fusion in the extension station were (19.11±4.03) Mpa and (16.32±3.72) Mpa respectively. The stress values of the L-fusion end plate were (9.13±0.01) Mpa and (4.92±1.01) Mpa respectively. (2) The stress of H-type fusing end plate was higher than that of L-type fusing end plate except for L-5 end plate at neutral position (P<0.05). (3) Choosing an interbody fusion device with a height of more than 3 mm in the same intervertebral space has a more stable biomechanics.

In order to investigate the role of sRNA OxyS in the pathogenicity of Salmonella typhi-murium infection,the OxyS gene deletion strain ATCC25241 △OxyS and the back-complemented strain ATCC25241 △OxyS/OxyS of Salmonella typhimurium ATCC25241 were constructed by using λRed homologous recombination technique.We investigated the effect of OxyS deletion on the biological characteristics and pathogenicity of Salmonella typhimurium ATCC25241.The re-sults showed that the deletion of OxyS did not affect the growth rate,the ability of biofilm forma-tion,and the ability of adhesion,invasion and intracellular survival of Salmonella typhimurium,but significantly reduced the motility of Salmonella typhimurium as well as its ability to survive in alkaline and oxidative environments.The results of mouse infection test showed that OxyS dele-tion caused a significant decrease in the virulence of Salmonella typhimurium in mice,and toxicity is reduced obviously.The qPCR results also showed that OxyS deletion could lead to changes in the transcript levels of a number of virulence-related genes of Salmonella typhimurium such as pipB,orf245,csgA,invH,tatA,sipA,sipB,and so on.The above results indicate that OxyS gene affects the biological characteristics and pathogenicity of Salmonella typhimurium and is an important virulence regulator of Salmonella typhimurium.

Objective To explore the role of ferroptosis in DIC through bioinformatics analysis of hub genes involved in ferroptosis in doxorubicin-induced cardiomyopathy(DIC),combined with in vitro experimental validation.Methods Divalent iron fluorescence staining confirms the occurrence of ferroptosis in myocardial cells of DIC.The GSE207737 dataset was retrieved from the Gene Expression Comprehensive Database(GEO)and intersected with the FerrDb database to identify ferroptosis-related genes.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses of the intersected genes and intersecting the genes obtained from LASSO regression analysis and SVM-SFR machine learning methods were used to obtain ferroptosis hub genes for DIC.Real-time PCR was used to validate H9C2 cells in the control and DIC model groups,and Western blotting was used to further validate those whose bioinformatics and real-time PCR results that did not match.Results Thirty-eight ferroptosis-related genes in DIC were identified,and GO and KEGG analyses showed that these genes mainly participate in cell metabolism.Five hub genes for ferroptosis in DIC were obtained using machine learning methods:Mpc1,Prdx1,Kdm4a,Alox 12b,and Tfrc.Through in vitro experiments,the mRNA expression levels of Mpc1,Prdx1,and Kdm4a were downregulated in the DIC model group compared to those in the control group(P＜0.001),whereas the mRNA expression level of Alox12b was upregulated(P＜0.001).There were no significant differences in the mRNA or protein expression levels of Tfrc(P＞0.05).Conclusion Mpc1,Prdx1,Kdm4a,and Alox12b are key genes involved in ferroptosis in doxorubicin-induced cardiomyopathy and potential targets for the prevention and treatment of doxorubicin-induced cardiomyopathy in ferroptosis.

Objective:To investigate the roles of simulated participants in the facilitation of medical scenarios simulation-based course and to provide a reference for the standardized construction of medical scenarios simulation-based course.Methods:Thirty scenario simulation-based teaching sessions on perioperative crisis events conducted during the 2022-2023 academic year were observed on-site. The performance of simulated participants in facilitating case execution and the skills used in facilitation were observed and recorded. At the end of the course, surveys regarding facilitation were administered to students, simulated participants, and instructors for analysis.Results:In the facilitation of 30 scenario simulation-based teaching sessions on perioperative crisis events, the roles of simulated participants included surgeon, anesthesia nurse, circuit nurse, and standardized patient. Two simulated participants accounted for 80.00% and three participants for 20.00% of the total sessions. The simulated participants performed excellently in helping the learners quickly integrate into the scenario and controlling the direction of the case, with an excellence rate of 90.00%-100.00%. However, they had some variations in driving the progress of the case and responding to unexpected situations, with an excellence rate of 50.00%-60.00%. The facilitation skills used by simulated participants included hinting, prompting, and instructing. The performance of facilitation was closely related to the use of skills by the simulated participants. Simulated participants with proficient skill usage significantly enhanced teaching effectiveness. Post-session surveys revealed that learners generally perceived simulated participants as having a positive impact on facilitation, and both simulated participants and instructors emphasized the need for strengthened communication prior to simulation-based teaching.Conclusions:The simulated participants played important roles in guiding learners, advancing case progression, and achieving teaching objectives. Instructors should not only consider the scripting of simulated participants during lesson planning but also prioritize their training and communication during course implementation.

Pancreatic cancer is highly aggressive and often diagnosed at an advanced stage,leaving most patients ineligible for radical resection.This study retrospectively analyzed four patients with locally advanced or advanced pancreatic cancer to evaluate the clinical efficacy and safety of high-intensity focused ultrasound(HIFU)ablation combined with chemotherapy as a neoadjuvant and conversion therapy.All cases were reviewed and individualized treatment plans were formulated through a multidisciplinary team evaluation.All patients received HIFU plus gemcitabine and nab-paclitaxel chemotherapy,with assessments of tumor volume,vascular involvement,surgical conversion,symptom relief,and adverse events.Three patients achieved marked tumor shrinkage and reduction of vascular invasion,enabling successful R0 resection without recurrence during follow-up.The remaining patient achieved disease stability,significant pain relief,and maintained good quality of life under repeated HIFU therapy.All treatments were well tolerated,and no severe adverse reactions occurred.The combination of HIFU and chemotherapy demonstrated synergistic local and systemic effects,effectively achieving tumor downstaging,improving resectability,and alleviating symptoms.As a safe,noninvasive,and repeatable therapeutic approach,this strategy offers a promising option for patients with advanced pancreatic cancer.Further large-scale prospective studies are warranted to validate its long-term efficacy and elucidate underlying mechanisms.

Objective To assess the accuracy and consistency of point-of-care testing(POCT)technology in detecting D-dimer(DDI),Procalcitonin(PCT),and N-terminal pro B-type natriuretic peptide(NT-proBNP)in whole blood samples,as well as to validate its feasibility for rapid clinical diagnosis.Methods From July 8 to August 22,2022,a total of 104 paired DDI whole blood and plasma samples,496 paired PCT whole blood and serum samples,and 77 paired NT-proBNP whole blood and serum samples were collected.The consistency and accuracy of test results between whole blood and plasma/serum samples were assessed using the Mann-Whitney U test,regression analysis,relative sensitivity,relative specificity,Youden's index,and Kappa value.Results The test results of DDI,PCT,and NT-proBNP in whole blood and plasma/serum samples demonstrated excellent consistency,with correlation coefficients of r2=0.951 2,r2=0.942 8,and r2=0.991 6,respectively,and all P-values exceeding 0.05.At the medical decision levels,for DDI(0.55 μg/mL),the relative sensitivity,rela-tive specificity,Youden index,and Kappa value were 94.3%,94.1%,0.88,and 0.87,respectively.For PCT(0.5 ng/mL and 2.0 ng/mL),the relative sensitivities were 97.4%and 89.0%,the relative specificities were 95.8%and 98.3%,the Youden indices were 0.93 and 0.87,and the Kappa values were 0.93 and 0.89,respectively.For NT-proBNP(125 pg/mL),the relative sensitivity was 94.1%,the relative specificity was 100%,the Youden index was 0.94,and the Kappa value was 0.87.These findings confirm the high accuracy of whole blood sample testing and the strong concordance between the two methods.Conclusions This study confirmed the efficacy of POCT technology for detecting DDI,PCT,and NT-proBNP in whole blood samples.The results showed a high level of consistency compared to traditional plasma/serum methods,thereby reinforcing the clinical applicability of POCT for rapid diagnosis.