BACKGROUND:Current osteoarthritis modeling methods include anterior cruciate ligament transection(ACLT)and ACLT combined with medial meniscal anterior horn resection.ACLT requires excessive postoperative exercise,which is time and labor-intensive.Complete removal of anterior horn of the medial meniscus can cause collateral damage and increase variability in modeling outcomes,requiring higher surgical skills from the surgeon. OBJECTIVE:To modify and simplify the traditional method to create animal osteoarthritis model and compare osteoarthritis symptoms of different modeling methods under a low-load exercise environment. METHODS:Forty-eight Sprague-Dawley rats were randomly assigned in four groups(n=12 per group):sham operation(complete exposure of the knee cavity of the left hind limb followed by suturing the joint cavity and skin),ACLT,ACLT+anterior horn resection(removal of the anterior horn of the medial meniscus)and ACLT+anterior horn tear(anterior horn tear of the medial meniscus).At 4 weeks after modeling,the rats were euthanized and their knee specimens were collected for gross observation,X-ray and CT scans,pathological observation,and PCR detection. RESULTS AND CONCLUSION:Gross observation:Mild meniscal wear was observed in the ACLT group.In the ACLT+anterior horn tear group,severe wear of the lateral condyle articular surface,mild wear of the medial condyle articular surface,severe meniscal wear,and full wear of the medial meniscus were observed.The ACLT+resection group showed severe wear of the lateral condyle articular surface,mild wear of the medial condyle articular surface,absence of the anterior horn of the medial meniscus,and meniscus wear area＞50%.Imaging examinations showed no significant difference among the four groups.However,the anterior tibial translocation sign was observed in the three operation groups and the anterior horn of the medial meniscus was missing in the ACLT+anterior horn resection group.Histopathological section observation:Hematoxylin-eosin,toluidine blue,and Sirius red staining showed smooth joint surfaces in the sham operation group and ACLT group;cartilage damage and matrix degradation were evident in the ACLT+anterior horn tear and ACLT+anterior horn transection groups,with less cartilage damage and matrix degradation in the ACLT+anterior horn tear group.PCR results showed higher mRNA expressions of interleukin 1β,interleukin 6,interleukin 8,tumor necrosis factor α,matrix metalloproteinase 1 and matrix metalloproteinase 3 and lower mRNA expressions of aggrecan in the ACLT+anterior horn tear group and ACLT+anterior horn resection group than in the sham operation group and ACLT group(P＜0.05).The mRNA expressions of interleukin 6,matrix metalloproteinase 1,and matrix metalloproteinase 3 were higher in the ACLT + anterior horn resection group than in the ACLT +anterior horn tear group(P＜0.05).To conclude,ACLT alone is less likely to induce osteoarthritis with obvious cartilage wear.ACLT combined with anterior horn resection or tear of the medial meniscus can induce obvious symptoms of osteoarthritis and achieve similar modeling effects.

Objective To observe the value of ultrasound-guided percutaneous ethanol injection(PEI)combined with microwave ablation(MWA)for treating thyroid benign partially cystic masses.Methods A total of 100 patients with single benign partially cystic mass who would undergo ultrasound-guided ablation treatment were prospectively enrolled.The patients were randomly assigned into PEI group(received PEI combined with MWA sequential ablation)or control group(received simple MWA),each n=50.Data before and after treatments were compared within groups,the therapeutic efficacy were compared between groups after treatments,and the value of sequential ablation was analyzed.Results Ultrasound-guided ablation was successfully performed for all 100 masses.During follow-up,5 cases in PEI group and 3 cases in control group were lost.The operation time of MWA,total MWA energy and patients'pain level during treatments in PEI group were all lower than those in control group(all P＜0.05).Significant difference of thyroid mass volumes were found before and 3,6 and 12 months after treatments in both groups(all P＜0.05).The volume reduction rate(VRR)in PEI group before and 1,3,6 and 12 months after treatments were all higher than that in control group(all P＜0.05).The success rate was 95.56％(43/45)in PEI group and 89.36％(42/47)in control group 12 months after treatments,respectively,without significant difference(P=0.451).There were significant differences of neck aesthetics scores and symptom scores before and 3,6 and 12 months after treatments in both groups(all P＜0.05).The incidence of complications in PEI group was 6.67％(3/45),while in control group was 14.89％(7/47),the former was lower than the latter(P＜0.05).Conclusion Ultrasound-guided PEI combined with MWA sequential ablation had better effect for treating thyroid benign partially cystic masses than single MWA.

Purpose To investigate the safety and effectiveness of ultrasound-guided microwave ablation(MWA)in the treatment of abdominal wall endometriosis(AWE).Materials and Methods A total of 17 patients(19 lesions)with AWE who underwent MWA in Beijing Friendship Hospital from August 2014 to June 2023 were retrospectively analyzed.Grey-scale and color Doppler flow ultrasonography,and contrast-enhanced ultrasonography were used to observe the lesions before and after treatment.The AWE lesion volume,volume reduction rate,pain relief,and complications were recorded 3,6,and 12 months after treatment to evaluate the treatment efficacy.Results Contrast-enhanced ultrasound showed that all lesions underwent successful treatment with single MWA.The average initial nodule volume was(7.46±5.82)ml,which decreased significantly to(4.32±2.76)ml,(2.47±1.68)ml,(1.72±1.16)ml at 3,6 and 12 months follow-up(t=0.423,P=0.005;t=0.198,P=0.001;t=0.556,P=0.002)with a mean volume reduction rate of(46.18±24.36)%,(61.43±18.72)%,(74.25±13.26)%,respectively.Notably,all 17 patients experienced a significant decrease or complete alleviation of periodic abdominal incision pain at 12-month after treatment.One patient experienced local skin burns after the procedure,while the remaining patients did not experience severe complications.Conclusion MWA is safe and effective for treating AWE,and further research is warranted.

Complicated crown root fracture is a serious combined fracture of the enamel,dentin,and cementum in dental trauma.The treatment method is complicated.During the procedure,the condition of pulp,periodontal,and tooth body should be thoroughly evaluated,and a multidisciplinary approach combined with sequential treatment is recom-mended.This case reported the different treatment and repair processes of one case of two affected teeth after complicat-ed crown root fracture of upper anterior teeth,including regrafting of broken crown after flap surgery at the first visit,di-rect resin repair to remove broken fragments,and pulp treatment and post-crown repair at the second visit.After 18 months of follow-up,the preservation treatment of the affected teeth with complicated crown root fracture was achieved.Therefore,fragment reattachment and post-crown restoration are feasible treatment options for children with complicated crown root fracture.

Objective:To investigate the performance of medical students with different cognitive styles and temperament types in the flipped classroom of pediatrics.Methods:A total of 85 medical students of the class of 2018 in eight-year program who studied the course of Pediatrics 2 in West China Medical School, Sichuan University, were selected and received the flipped classroom teaching of pediatrics. The cognitive style figure test was used to investigate the cognitive style of students, and the temperament self-test questionnaire was used to investigate the temperament type of students. The methods such as the cluster analysis, the ANOVA analysis of variance, the Pearson correlation analysis, and the chi-square test were used to describe the distribution of flipped classroom scores and related differences between the students with different cognitive styles and temperament types.Results:There were four temperament types of these students, i.e., choleric and sanguine temperament, sanguine and phlegmatic temperament, melancholic temperament, and choleric temperament, accounting for 28.24%, 23.53%, 27.06%, and 21.18%, respectively. There were two cognitive styles of field independence and field dependence, accounting for 51.76% and 48.24%, respectively. There was a significant difference in flipped classroom scores between the students with different cognitive styles ( t=3.18, P<0.05), while there was no significant difference in such scores between the students with different temperament types ( F=0.38, P>0.05). The correlation analysis showed that the score of phlegmatic temperament was significantly negatively correlated with flipped classroom scores ( r=-0.283, P<0.05), and the score of cognitive test was significantly positively correlated with flipped classroom scores ( r=0.346, P<0.05). Conclusions:In the flipped classroom teaching of pediatrics, it is necessary to flexibly apply specific interaction and evaluation methods in students with different temperament types and cognitive styles and grasp the relationship between cooperative learning and independent learning. The design of different links of flipped classroom should be further improved.

Objective:To investigate the value of systemic inflammatory response syndrome (SIRS), pediatric sequential organ failure assessment (pSOFA) and pediatric critical illness score (PCIS) in predicting mortality of pediatric sepsis in pediatric intensive care units (PICU) from Southwest China.Methods:This was a prospective multicenter observational study. A total of 447 children with sepsis admitted to 12 PICU in Southwest China from April 2022 to March 2023 were enrolled. Based on the prognosis, the patients were divided into survival group and non-survival group. The physiological parameters of SIRS, pSOFA and PCIS were recorded and scored within 24 h after PICU admission. The general clinical data and some laboratory results were recorded. The area under the curve (AUC) of the receiver operating characteristic curve was used to compare the predictive value of SIRS, pSOFA and PCIS in mortality of pediatric sepsis.Results:Amongst 447 children with sepsis, 260 patients were male and 187 patients were female, aged 2.5 (0.8, 7.0) years, 405 patients were in the survival group and 42 patients were in the non-survival group. 418 patients (93.5%) met the criteria of SIRS, and 440 patients (98.4%) met the criteria of pSOFA≥2. There was no significant difference in the number of items meeting the SIRS criteria between the survival group and the non-survival group (3(2, 4) vs. 3(3, 4) points, Z=1.30, P=0.192). The pSOFA score of the non-survival group was significantly higher than that of the survival group (9(6, 12) vs. 4(3, 7) points, Z=6.56, P<0.001), and the PCIS score was significantly lower than that of the survival group (72(68, 81) vs. 82(76, 88) points, Z=5.90, P<0.001). The predictive value of pSOFA (AUC=0.82) and PCIS (AUC=0.78) for sepsis mortality was significantly higher than that of SIRS (AUC=0.56) ( Z=6.59, 4.23, both P<0.001). There was no significant difference between pSOFA and PCIS ( Z=1.35, P=0.176). Platelet count, procalcitonin, lactic acid, albumin, creatinine, total bilirubin, activated partial thromboplastin time, prothrombin time and international normalized ratio were all able to predict mortality of sepsis to a certain degree (AUC=0.64, 0.68, 0.80, 0.64, 0.68, 0.60, 0.77, 0.75, 0.76, all P<0.05). Conclusion:Compared with SIRS, both pSOFA and PCIS had better predictive value in the mortality of pediatric sepsis in PICU.

Objective To compare the size discrepancy between ultrasonic and pathological measurement of solitary cN0M0 papillary thyroid microcarcinoma(PTMC),and to explore their correlation with lymph node metastasis.Methods From April 2021 to January 2022,234 patients with solitary cN0M0 PTMC who received thyroid lobectomy or total thyroidectomy in the Department of Thyroid and Breast Surgery of Nanjing University of Chinese Medicine,Affiliated Hospital of Integrated Traditional Chinese and Western Medicine were analyzed retrospectively.The size discrepancy between ultrasonic and pathological measurement were compared,and the risk factors of central lymph node metastasis were analyzed.Results The mean of maximum diameter of PTMC measured by ultrasound was 6.8(range 5.6 to 8.4)mm,which was significantly bigger than that measured by pathology 5.0(range 4.0 to 7.0)mm(P=0.000).Of them,37.2%of the tumor size measured by ultrasound is consistent with pathology,61.1%of the tumor size measured by ultrasound is bigger than that measured by pathology,and only 1.7%of the tumor size measured by ultrasound is smaller than that measured by pathology.There was a linear correlation between the diameter measured by ultrasound and pathology.And the regression equation can be expressed as:pathological diameter=0.799×ultrasonic diameter-0.221.In addition,28.6%patients had central lymph node metastasis.Multivariate Logistic regression analysis showed that the diameter measured by pathology is a risk factor for central lymph node metastasis in patients(OR=17.845,95%CI:2.507-127.025,P=0.004),and the cutoff value is 5.5 mm which corresponded to the diameter measured by ultrasound as 7.2 mm.Conclusions The sizes of solitary cN0M0 PTMC measured by ultrasound and pathology are different but also correlated.PMTC with pathological diameter>5.5 mm with its corresponding ultrasonic diameter as 7.2 mm indicated an increased risk of central lymph node metastasis.

Objective:To grasp the distribution of fine antigenic epitope profiles of nucleoprotein (NP) and glycoprotein (GP) fragments of Crimean-Congo hemorrhagic fever virus (CCHFV) and to clarify the value of dominant antigenic epitopes in laboratory testing of Crimean-Congo hemorrhagic fever (CCHF).Methods:In a minimal synthetic short peptide consisting of 8 amino acids was segmentally expressed by CCHFV YL04057 strain using a modified bio-peptide synthesis method from 2014 to 2021 in the laboratory of Xinjiang University, College of Life Sciences. Using CCHFV polyclonal antibody or monoclonal antibody 14B7 (IgM) or CCHFV-positive sheep serum as antibodies, the minimal antigenic epitopes (BCEs) with antigenic activity on NP and GP fragments were identified by immunoblotting, and the obtained BCEs with sequence polymorphism were spatially clustered with CCHFV from different regions using the neighbor-joining method to determine the combination mode of BCEs with geographical correlation of regional distribution, to explore its application in establishing serological diagnosis. A prokaryotic expression plasmid (pET-32a), an E. coli expression plasmid (pGEX-KG) and a prokaryotic expression plasmid with an incomplete glutathione (GST188) tag (pXXGST-ST-1) were used to construct and express six dominant antigenic epitopes of different peptide lengths on NP fragments, and an indirect Enzyme-linked immunosorbent assay (ELISA) was established. CCHF sheep serum identified by immunofluorescence assay (IFA) was used as a control, and the specificity, sensitivity and overall compliance of the recombinant proteins with different peptide lengths of antigenic epitopes with IFA assay results were statistically analyzed. Results:CCHFV, NP and GP fragments had a total of 30 antigenically active BCEs, among which the core intermediate fragment NP2 (aa 170 th-305 th), which had a concentration of antigenic epitopes in the NP fragment, has 6 BCEs, and the NP1 (aa 1 st-200 th) and NP3 (aa 286 th-482 nd) at both ends have 9 BCEs; the Gc (aa 1 st-558 th) and Gn (aa 533 th-708 th) fragments of the GP fragment have 14 BCEs and a long antigenic peptide (AP) containing 15 amino acids, and the amino acid sequence homology of the NP fragment BCEs was 97.1% and that of the GP fragment BCEs was 89.1%. There was a significant difference ( P=0.0281, P<0.05). Among the 9 BCEs with sequence polymorphism in the GP fragment, 6 combined BCEs from GnEc1, GnE2, GnE4, GcE3, GcE6 and GcAP-4 (Ap) could cluster 15 CCHFV strains from different regions of the world into 5 geographical taxa, AsiaⅠ, AsiaⅡ, AficaⅠ, AficaⅡ and Europe. The constructs expressing PET-32a-NP (full length), PGEX-KG-NP2 (aa 170 th-305 th), pGEX-KG-NP2-1 (aa 235 th-275 th), PGEX-KG-NP2-1-1 (aa 237 th-256 th), pXXGST-1-NP2-1-2 (aa 250 th-265 th) and PGEX KG-NP2-1-3 (aa 260 th-276 th), six recombinant proteins CCHFV NP rabbit polyclonal antiserum (pAb) Western Blotting reaction positive, 33 sheep sera tested by IFA XHF as a reference, the sensitivity of the assay established by indirect ELISA using the recombinant proteins constructed from two fragments of NP2 and NP2-1 as antigens. The sensitivity, specificity and overall compliance were the best, with 73.4% (11/15) and 66.7% (10/15) for sensitivity, 100% (18/18) and 94.4% (17/18) for specificity, and 87.9% (29/33) and 81.8% (27/33) for overall compliance. Conclusion:CCHFV NP and GP are distributed with a high number of BCEs with antigenic immunoreactivity, among which the dominant antigenic epitopes are of high value in the laboratory serological diagnosis of CCHF.

Objective:To study the application of establishing WeChat group combined with PBL teaching mode in the practice of pediatric orthopaedics.Methods:The study was conducted among 36 postgraduates of "5+3" pediatrics and 22 postgraduates of orthopedic surgery of Batch 2012 who had practice in Department of Orthopaedics, Children's Hospital of Chongqing Medical University from September 2018 to August 2019, and they were randomized into control group and experimental group, with 29 students in each group. The control group was taught by traditional PBL mode, while the experimental group was taught by WeChat group combined with PBL mode. At the time of leaving the department, the two groups were assessed by theoretical knowledge, practical operation and questionnaire satisfaction, thus evaluating the teaching effects. The SPSS 23.0 was used to conduct t test and chi-square test. Results:The average scores of theoretical knowledge test (91.28±2.89) and practical operation test (87.44±2.94) in the experimental group were significantly higher than those in the control group (87.39±3.53) and (79.06±3.84), with statistically significant differences ( P<0.05). In the survey of teaching satisfaction, the experimental group[96.55%(27/29)] was significantly higher than the control group[61.90%(21/29)], with statistically significant differences ( P<0.05). Conclusion:The establishment of WeChat group and the combination of PBL teaching model can significantly improve the teaching effect and students' satisfaction in the practice of pediatric orthopaedics, which is worthy of further promotion and application.

A cross-sectional study was conducted on 1 052 patients with coronary heart disease (CHD) who visited 10 community health service centers in Chaoyang and Haidian districts of Beijing from March 2019 to September 2019. Basic information, medical history, cardiovascular risk factors, β-blocker use, height, weight, blood pressure level and resting heart rate were collected by face-to-face interview;biochemical tests and on-site physical examination were performed;and the influencing factors of heart rate control were analyzed by logistic regression. There were 563 males (53.5%) and 489 females(46.5%),with a mean age of (66.7±9.5) years. The rate of β-blockers use was 43.6% (459/1 052). The average resting heart rate was (70±8)/min, and only 14.5% (153/ 1 052) patients had the heart rate under control. The resting heart rate control rate in patients with β-blockers use was 17.9% (82/459), higher than that of those without β-blockers use [12.0% (71/593), χ 2=7.23, P=0.007]. Moderate leisure activities were beneficial to the control of resting heart rate ( OR=2.14, 95% CI: 1.26-3.62). The study shows that β-blockers use and resting heart rate control in CHD patients in Beijing community health institutions were both at low levels, and the resting heart rate was not well controlled even in patients taking beta-blockers.