Objective: To investigate the effect of human adipose-derived mesenchymal stem cells (hASCs) exosomes on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) extracted from osteoporotic mice, and to evaluate the effect of hASCs exosomes on preventing bone loss induced by estrogen deficiency. Methods: hASCs exosomes were extracted by ultracentrifugation. The osteoporotic mice were established by bilateral ovariectomy (OVX). BMSCs were isolated from osteo-porotic mice and cultured for further analysis. In the experimental group, these BMSCs were exposed to an osteogenic induction medium supplemented with hASCs exosomes to evaluate their potential effects on osteogenesis. In contrast, the control group was treated with the same osteogenic induction medium, but without the addition of hASCs exosomes, to serve as a baseline comparison for the study. To comprehensively assess the osteogenic differentiation of BMSCs influenced by hASCs exosomes, alkaline phosphatase (ALP) staining, ALP activity quantitative analysis and quantitative reverse transcription polymerase chain reaction (qPCR) were performed. These evaluations provided critical insights into the role of hASCs exosomes in promoting osteoblast differentiation and bone formation in osteoporotic conditions. The fluorescence labeled hASCs exosomes were injected via the tail vein to observe the biodistribution of exosomes. Two weeks after OVX, the mice were divided into three groups: The experimental group consisted of estrogen-deficient mice receiving hASCs exosome injections; the negative control group consisted of estrogen-deficient mice receiving phosphate-buffered saline (PBS) injections; and the positive control group consisted of mice that underwent Sham surgery and received PBS injections.The injections were administered once every 3 days, for a total of 8 injections. Afterward, the femurs were collected from the mice, and micro-computed tomography (micro-CT) was performed to measure bone mineral density and conduct bone morphometric analysis. Results: hASCs exosomes were successfully extracted using ultracentrifugation. After the induction by hASCs exosomes, ALP staining and ALP activity in the BMSCs extracted from osteoporotic mice were significantly enhanced, the expression of osteogenesis related genes in BMSCs were significantly up-regulated. More trabecular bone and higher bone mineral density were observed in estrogen-deficient mice injected with hASCs exosomes compared with estrogen-deficient mice injected with PBS, and there was no significant decrease in bone mineral density compared with the Sham operation group. Conclusion: hASCs exosomes promoted the osteogenic differentiation of BMSCs extracted from osteoporotic mice. hASCs exosomes prevented bone loss induced by estrogen deficiency.

Objective: To identify the role of gene silencing or overexpression of Nemo-like kinase (NLK) during the process of neural differentiation of human mesenchymal stem cells (hBMSCs), and to explore the effect of NLK downregulation by transfection of small interfering RNA (siRNA) on promoting neuralized tissue engineered bone regeneration. Methods: NLK-knockdown hBMSCs were established by transfection of siRNA (the experimental group was transfected with siRNA silencing the NLK gene, the control group was transfected with control siRNA and labeled as negative control group), and NLK-overexpression hBMSCs were established using lentivirus vector transfection technique (the experimental group was infected with lentivirus overexpressing the NLK gene, the control group was infected with an empty vector lentivirus and labeled as the empty vector group). After neurogenic induction, quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression of neural-related gene, and Western blot as well as immunofluorescence staining about several specific neural markers were used to evaluate the neural differentiation ability of hBMSCs.6-week-old male nude mice were divided into 4 groups: ① β-tricalcium phosphate (β-TCP) group, ② β-TCP+ osteogenic induced hBMSCs group, ③ β-TCP+ siRNA-negative control (siRNA-NC) transfection hBMSCs group, ④ β-TCP+ siRNA-NLK transfection hBMSCs group. Four weeks after the subcutaneous ectopic osteogenesis models were established, the osteogenesis and neurogenesis were detected by hematoxylin-eosin (HE) staining, Masson staining and tissue immunofluorescence assay. Statistical analysis was conducted by independent sample t test. Results: After gene silencing of NLK by siRNA in hBMSCs, neural-related genes, including the class Ⅲ β-tubulin (TUBB3), microtubule association protein-2 (MAP2), soluble protein-100 (S100), nestin (NES), NG2 proteoglycan (NG2) and calcitonin gene-related peptide (CGRP), were increased significantly in NLK-knockdown hBMSCs compared with the negative control group(P < 0.05), and the expression levels of TUBB3 and MAP2 of the NLK silencing group were also increased. Oppositely, after NLK was overexpressed using lentivirus vector transfection technique, TUBB3, MAP2, S100 and NG2 were significantly decreased in NLK-overexpression hBMSCs compared with the empty vector group (P < 0.05), and the expression level of TUBB3 was also decreased. 4 weeks after the subcutaneous ectopic osteogenesis model was established, more mineralized tissues were formed in the β-TCP+ siRNA-NLK transfection hBMSCs group compared with the other three groups, and the expression of BMP2 and S100 was higher in the β-TCP+ siRNA-NLK transfection hBMSCs group than in the other groups. Conclusion: Gene silencing of NLK by siRNA promoted the ability of neural differentiation of hBMSCs in vitro and promoted neuralized tissue engineered bone formation in subcutaneous ectopic osteogenic models in vivo in nude mice.

Objective: To investigate the expression and possible regulatory mechanism of miR-34a in the lung tissue of neonatal rat model of bronchopulmonary dysplasia (BPD) induced by hyperoxia. Methods: In the study, 80 newborn SD rats were randomly divided into hyperoxia group (FiO₂=60%) and air group (FiO₂=21%) within 2 hours after birth, 40 rats per group. Lung tissue samples of the SD rats in each group were extracted on the 1st, 7th, 14th and 21st days after birth, and the pathological changes of lung tissue were observed under light microscope after HE staining. The number of radial alveolar counts (RAC) and the mean alveolar diameter (MAD) and the thickness of alveolar septal thickness (AST) were measured to evaluate the development of alveoli. Real-time fluorescence quantitative PCR was used to detect the expression of miR-34a, angiopoietin-1 (Ang-1) and tyrosine kinase receptor-2 (Tie-2) in lung tissue of rats in hyperoxia group and air group at different time points. Enzyme-linked immunosorbent assay (ELISA) was used to detect the proteins expression of Ang-1 and Tie-2 in the lung tissues of the two groups at different time points. Results: The weight of rats in the hyperoxia group on the 7th, 14th and 21st days after birth was significantly lower than that in the air group (P all < 0.05). With the prolongation of oxygen exposure, the number of alveoli decreased, the volume increased, the structure simplified, the alveolar cavity enlarged obviously and the alveolar septum thickened in the hyperoxia group. On the 7th, 14th and 21st days after birth, the RAC in the hyperoxia group was significantly lower than that in the air group (P all < 0.05). Compared with the air group, MAD and AST increased significantly on the 7th, 14th and 21st days after birth in the hyperoxia group, and the difference was statistically significant (P all < 0.05). The expression level of miR-34a in lung tissue of hyperoxia group was significantly higher than that of air group on the 7th, 14th and 21st days after birth, and the difference was statistically significant (P all < 0.05). Compared with the air group at the same time point, the expression levels of Ang-1 and Tie-2 mRNA and protein in the hyperoxia group were lower than those in the air group on the 14th and 21st days after birth (P all < 0.05). Conclusion: The new BPD model of newborn SD rats can be successfully established by continuous exposure to 60% hyperoxia. The expression of miR-34a was up-regulated in the lung tissue of the new BPD model of neonatal rats. MiR-34a may play an important role in the occurrence and development of BPD by regulating Ang-1/Tie-2 signal pathway.

Objective: To explore the changes of CKLF-like MARVEL transmembrane domain-containing 6 (CMTM6) and programmed death-ligand 1 (PD-L1) expression in gastric mucosal epithelial cells after Helicobacter pylori infection and the regulation of CMTM6 on PD-L1, and to analyze the mRNA expression differences before and after CMTM6 gene knock-out in helicobacter pylori infected gastric epithelial cells by microarray analysis. Methods: The standard Helicobacter pylori strain ATCC 26695 was co-cultured with human gastric epithelial cell GES-1 for 6, 24 and 48 hours, and the mRNA and protein levels of CMTM6 and PD-L1 were detected by real-time quantitative PCR and Western blot. Using CRISPR/Cas9 to construct CMTM6 gene knockout plasmid and knockout CMTM6 gene of GES-1 cells. Helicobacter pylori was co-cultured with CMTM6 gene knockout and wild type GES-1 cells for 48 hours to detect PD-L1 transcription and protein level changes, and CMTM6 gene knockout GES-1 cells were treated with the proteasome inhibitor MG-132 to detect the changes in PD-L1 protein levels. Agilent Human ceRNA Microarray 2019 was used to detect the differentially expressed genes in CMTM6 gene knockout and wild-type GES-1 cells co-cultured with Hp for 48 hours, and the signal pathway of differentially expressed genes enrichment was analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Results: The mRNA and protein levels of CMTM6 and PD-L1 in GES-1 cells were significantly up-regulated after Helicobacter pylori infection, and CMTM6 mRNA was most significantly up-regulated 48 hours after infection. After CMTM6 gene knockout, the CD274 gene transcription level of Helicobacter pylori infected GES-1 cells did not change significantly, but PD-L1 protein level was significantly down-regulated, and the PD-L1 level increased after the application of proteasome inhibitor MG-132. After CMTM6 gene knockout, 67 genes had more than two times of differential expression. The transcription levels of TMEM68, FERMT3, GPR142, ATP6V1FNB, NOV, UBE2S and other genes were significantly down-regulated. The transcription levels of PCDHGA6, CAMKMT, PDIA2, NTRK3, SPOCK1 and other genes were significantly up-regulated. After CMTM6 gene knockout, ubiquitin-conjugating enzyme E2S (UBE2S) gene expression was significantly down-regulated, which might affect protein ubiquitination degradation. After CMTM6 gene knockout, adrenoceptor alpha 1B (ADRA1B), cholinergic receptor muscarinic 1 (M1), CHRM1, platelet activating factor receptor (PTAFR) gene expression was significantly up-regulated. Conclusion: Helicobacter pylori infection up-regulates the expression level of CMTM6 in gastric mucosa cells, and CMTM6 can stabilize PD-L1 and maintain the protein level of PD-L1. CMTM6 gene knockout may affect biological behaviors such as protein ubiquitination and cell surface receptor expression.

Objective: To investigate the biological activity and antitumor effect of pegylated recombinant human interleukin 2 (PEG-rhIL-2) obtained by site-specific conjugation of polyethylene glycol (PEG) with non-natural amino acids, and to explore its antitumor mechanism. Methods: The binding activities of PEG-rhIL-2 at three different sites (T41, Y45, and V91) to human interleukin 2 receptors α (IL-2R_α) and β (IL-2R_β) and were detected by surface plasmon resonance (SPR) technology. Western blot was used to detect the levels of the Janus kinase-signal transducer and activator of transcription 5 (JAK-STAT5) signaling pathway activated by different doses of rhIL-2 and PEG-rhIL-2 in CTTL-2 and YT cells. Blood was collected after a single administration in mice to detect the drug concentration at different time points and evaluate the pharmacokinetic parameters of Y45-PEG-rhIL-2. Mouse hepatoma cell line Hepa1-6, pancreatic cancer cell line Pan-02, and colon cancer cell line MC-38 were selected. Tumor models were constructed in C57BL/6 mice. Different doses of Y45-PEG-rhIL-2 and excipient control were administrated respectively to evaluate the tumor suppression effect of the drug. In the MC-38 colon cancer model, the tumor suppression effect of Y45-PEG-rhIL-2 combined with anti-programmed death-1 (PD-1) monoclonal antibody was evaluated. Hepa1-6 mouse tumor models were constructed and rhIL-2, Y45-rhIL-2 and Y45-PEG-rhIL-2 were administrated respectively. The proportion of tumor-infiltrating lymphocytes was analyzed by flow cytometry. Results: The SPR detection results showed that the binding activities of PEG-rhIL-2 to IL-2R_α/IL-2R_β were both reduced. The affinity of Y45-PEG-rhIL-2 to IL-2R_α was reduced to approximately 1/250, and its affinity to IL-2R_β was reduced to 1/3. Western blot results showed that the activity of Y45-PEG-rhIL-2 in stimulating JAK-STAT5 signaling in CTLL-2 cells expressing heterotrimeric IL-2 receptor complex IL-2R_αβγwas reduced to approximately 1/300, while its activity in YT cells expressing heterodimeric IL-2 receptor complex IL-2R_βγwas reduced to approximately 1/3. The pharmacokinetic evaluation after a single dose in the mice showed that the elimination half-life of Y45-PEG-rhIL-2 was 17.7 h. Y45-PEG-rhIL-2 has pharmacokinetic characteristics superior to those of rhIL-2. Y45-PEG-rhIL-2 showed dose-dependent tumor suppression activity, and the combination of Y45-PEG-rhIL-2 and anti-PD-1 antibody had a better tumor-inhibiting effect than the single use of Y45-PEG-rhIL-2 or anti-PD-1 antibody. Flow cytometry analysis demonstrated that 72 h after the administration of Y45-PEG-rhIL-2, the proportion of tumor-infiltrating cytotoxic T lymphocytes (CD8⁺T cells) increased by 86.84%. At 120 h after administration, the ratio of CD8⁺T cells to regulatory T cells (Treg) increased by 75.10%. Conclusion: Y45-PEG-rhIL-2 obtained by site-specific conjugation via non-natural amino acids changed its receptor binding activity and inhibited tumor growth in dose-dependent manner in multiple tumor models by regulating CD8⁺T cells.

Objective: To observe the dynamic changes of microvascular injury and repair in the penumbra of traumatic brain injury (TBI) rats with effective cerebral perfusion microvascular imaging using optical coherence tomography angiography (OCTA). Methods: Transparent closed cranial windows were placed in craniotomy rats after TBI caused by weight drop. All the rats in TBI group and control group underwent head MRI examination on the first postoperative day, and the changes of cerebral cortical microvessel density were measured by OCTA through cranial windows on d0, d2, d4, d6, and d8. On the second day after the operation, the same number of rats in the two groups were selected to complete the immunohistochemical staining of brain tissue with pimonidazole, an indicator of hypoxia. Results: MRI T2W1 and immunohistochemical staining demonstrated that edema and hypoxia in the traumatic brain tissue extended deeply throughout the entire cortex. OCTA showed that the cortical surface veins of the rats in both groups were significantly dilated and tortuous after operation, and recovered to the postoperative day level on d8. The effective perfusion microvessel density of the rats in both groups gradually recovered after a temporary decrease, and the TBI group decreased from 39.38%±4.48% on d0 to 27.84%±6.01% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 61.71%±7.69% on d8, which was significantly higher than that on d0, d2, and d4 (P < 0.05). The control group decreased from 44.59%±7.78% on d0 to 36.69%±5.49% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 51.92%±5.96% on d8, which was significantly higher than that on d2, and d4 (P < 0.05). Comparing the two groups, the effective perfusion microvessel density in the TBI group was significantly lower than that in the control group on d2 (P=0.021), and significantly higher than that in the control group on d8 (P=0.030). Conclusion: OCTA can be used as a method of imaging and measurement of effective perfusion microvessels in the injured cerebral cortex of TBI rats. After TBI, the effective perfusion microvessel density in the wound penumbra gradually recovered after decreasing, and increased significantly on d8.

Objective: To study incident and clinical characteristics of the coronary microcirculation dysfunction (CMD) in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI) by myocardial contrast echocardiography (MCE) and to explore the predictive value of CMD for in-hospital acute heart failure event. Methods: One hundred and forty five patients with AMI who had received PCI and completed MCE during hospitalization in Peking University People' s Hospital from November 2015 to July 2021 were enrolled in our study. The patients were divided into CMD group and normal group according to the coronary microcirculation status detected by MCE. Clinical data and MCE data of the two groups were collected and analyzed. The acute heart failure event during hospitalization was described. A multivariate Logistic regression model was built to analyze the risk of acute heart failure in patients with CMD. A receiver operating characteristic (ROC) curve was drawn to evaluate the value of CMD in predicting acute heart failure event. Results: CMD detected by MCE occurred in 87 patients (60%). Compared with normal group, patients with CMD had higher troponin I (TnI) peak level [52.8 (8.1, 84.0) μg/L vs. 18.9 (5.7, 56.1) μg/L, P=0.005], poorer Killip grade on admission (P=0.030), different culprit vessel (P < 0.001) and more patients had thrombolysis in myocardial infarction (TIMI) flow pre-PCI less than grade 3 in culprit vessel (65.1% vs. 43.1%, P=0.025). Meanwhile, patients with CMD had poorer left ventricular ejection fraction (LVEF) [52% (43%, 58%) vs. 61% (54%, 66%)], poorer global longitudinal strain (GLS) [-11.2% (-8.7%, -14.0%) vs.-13.9% (-10.8%, -17.0%)] and worse wall motion score index (WMSI) (1.58±0.36 vs. 1.25± 0.24) (P all < 0.001). Acute left heart failure happened in 13.8% of the CMD patients, which were significant higher than that in the patients with normal coronary microcirculation perfusion (1.7%, P=0.013). After correcting for the culprit vessel, the TIMI flow pre-PCI in the culprit vessel and the peak TnI value, the risk of acute left heart failure in the patients with CMD was still high (OR=9.120, 95%CI: 1.152-72.192, P=0.036). The area under ROC curve (AUC) was 0.677 (95%CI: 0.551-0.804, P=0.035). Conclusion: The incidence of CMD detected by MCE in patients with AMI post-PCI was 60%. Patients with CMD have a higher risk of acute left heart failure during hospitalization.

Objective: To investigate the effect of intraoperative blood salvage autotransfusion on local recurrence and long-term metastasis of patients after carotid body tumor resection. Methods: We retrospectively reviewed a consecutive series of 61 patients undergoing elective carotid body tumor resection from August 2009 to December 2020. Among them, 14 received intraoperative blood salvage autotransfusion (autotrasfusion group) and 47 did not (non-autotransfusion). Data of general information, surgical status and postoperative follow-up results were collected. Results: The proportion of Shamblin Ⅲ in the autotransfusion group was 85.7%, which was significantly higher than 31.9% in the non-autotransfusion group (P=0.003). The average operation time of the 14 patients in the autotransfusion group was (264±84) min, intraoperative blood loss was 1 200 (700, 2 700) mL, and autologous blood transfusion was 500 (250, 700) mL. Of these, 8 patients (57%) required concomitant allogeneic blood with 400 (260, 400) mL of allogeneic blood. The average operation time of the 47 patients in the non-autotransfusion group was (153±75) min, and the intraoperative blood loss was 300 (100, 400) mL. Of these, 6 (13%) required allogeneic blood transfusion, and 520 (400, 520) mL of allogeneic blood was used. Compared with the non-autotransfusion group, the average operation time in the autologous blood transfusion group was significantly longer (P < 0.001), and the intraoperative blood transfusion volume was larger (P=0.007). Of the 14 patients undergoing autotransfusion, 8 (57%) needed allogeneic blood at the same time; while in the 47 non-autologous transfusion patients, 6 (13%) needed allogeneic blood transfusion. The proportion of autotransfusion group using allogeneic blood at the same time was even higher (P=0.002). The incidence of nerve injury within 30 days after surgery was 29.5%, and there was no significant difference between the two groups. No early deaths occurred. The average follow-up was (76±37) months. One case of local recurrence occurred in the non-autotransfusion group. There was no distant metastasis. There were no tumor-related deaths. The estimated 5-year and 10-year overall survival rates were 96.4% and 83.8%, respectively. There was no significant difference in overall survival between the two groups (P=0.506). Conclusion: The use of intraoperative blood salvage autotransfusion increased no risk of local recurrence and distant metastasis in patients with carotid body tumor, which is safe and effective in carotid body tumor resection.

Objective: To compare the differences of plasma valine level between autistic and healthy children, and to explore the relationship between plasma valine level and developmental quotient in children with autism. Methods: In this study, a total of 29 autistic children and 30 typically developing children of the same age range were recruited as the autistic group and the control group. The childhood autism rating scale (CARS) was used to assess autistic core symptoms and severity in the autistic children. Children's developmental quotient was evaluated by Gesell developmental schedules (GDS), and plasma valine level was measured by high performance liquid chromatography-tandem mass spectrometry. The correlation between plasma valine level and developmental quotient scores in the autistic group was analyzed. Results: The plasma level of valine in the autism group was significantly lower than in the control group (P < 0.05). Children in the autism group got significantly lower scores in the adaption, gross motor, fine motor, language function and personal/social function subscales in GDS than in the control group (P < 0.000 1). Plasma valine level in the autism group showed significant positive correlations with scores of the fine motor (r=0.441, P < 0.05) and personal/social function (r=0.437, P < 0.05) subscales in GDS, but showed no significant correlations with scores of the adaption, gross motor and language function subscales in GDS (P>0.05). According to the criteria of CARS, children in the autism group were subdivided into the mild to moderate subgroup and the severe subgroup based on the severity of the autistic symptoms. Compared with children in the mild to moderate subgroup, children in the severe subgroup got significantly lower scores in the adaption, fine motor, language function and personal/social function subscales in GDS (P < 0.05), while there was no significant difference between the two subgroups in gross motor scores and plasma valine level (P>0.05). Conclusion: The level of valine in plasma of autistic children is relatively lower, and there is a certain relationship between plasma valine level and the fine movement and personal/social function among children with autism.

Objective: To explore whether streptococcal infection may aggravate renal damage in children with Henoch-Schönlein purpura nephritis and its possible mechanism. Methods: In the study, 485 children diagnosed with Henoch-Schönlein purpura nephritis from July 2015 to December 2019 were selected to analyze their clinical data retrospectively. According to the diagnosis of discharge, whether it was combined with streptococcal infection, the children were divided into two groups. The experimental group contained 91 children with Henoch-Schönlein purpura nephritis combined with streptococcal infection, and there were 394 children who were not infected with Streptococcus in the control group. Suitable test items were preliminarily selected through artificial neural network, and then data analysis was performed through SPSS 23.0. Results: The children with Henoch-Schönlein purpura nephritis infected with streptococcus had statistically significant differences compared with the uninfected children in the test items of urine protein, liver and kidney function, immunoglobulin and complement. Anti-streptolysin O had mild correlation with IgG (Spearman r=-0.328), fibrin degradation products (Spearman r=-0.207), total protein (Spearman r=-0.202) and globulin (Spearman r=-0.223). Compared with the children who were not infected with streptococcus, the differences of the average levels of age (P=0.001), IgG (P < 0.001), fibrin degradation products (P=0.019), total protein (P < 0.001), globulin (P < 0.001), IgA (P < 0.001), IgM (P=0.003), complement 3 (P=0.016), complement 4 (P=0.002), albumin/globulin ratio (P=0.007), alkaline phosphatase (P=0.036), and estimated glomerular filtration rate (P=0.039) in the infected children were statistically significant. In order to explore the risk factors of kidney damage in the children with Henoch-Schönlein purpura nephritis, Logistic regression was performed using anti-streptolysin O, age, immunoglobulin and complement as independent variables, urine protein detection parameters, liver and kidney functions as dependent variables. Age ≤10 years old and hypocomplementemia might be risk factors for aggravating renal damage in the children with Henoch-Schönlein purpura nephritis. Conclusion: Streptococcal infections may aggravate renal damage in children with Henoch-Schönlein purpura nephritis, in which hypocomplementemia, inflammation, fibrinolysis and disorders of coagulation perhaps play an important role. Children with streptococcal infection should be treated with anti-infective treatment in time and necessarily, and followed up after discharge regularly.

Objective: To explore the effect of concurrent administration of goserelin for ovarian function protection on the pathological complete response (pCR) rate and objective response rate (ORR) of neoadjuvant chemotherapy (NAC) in young breast cancer patients. Methods: The study enrolled breast cancer patients aged 18-45 with clinical stages ⅡA~ⅢC from January 2016 to May 2020. According to patients' willingness, they were divided into two groups: Those who chose to receive goserelin to protect ovarian function during NAC (goserelin group) and those who did not (chemotherapy group). The pCR rate and ORR were compared between the two groups, and subgroup analysis was conducted for patients with different molecular subtypes. Results: A total of 93 patients were included in this study (31 in the goserelin group and 62 in the chemotherapy group). After propensity score weighting (PSW) adjustment, baseline data such as age, preoperative clinical stage, postoperative pathological stage, pa-thological type, hormone receptor status, human epidermal growth factor receptor 2 (HER2) and Ki-67 expression, molecular subtypes, and chemotherapy regimens were well-matched between the two groups. There was no significant difference in the pCR rate between the goserelin group and the chemotherapy group, with rates of 29.0% and 25.8%, respectively (P=0.741). Similarly, there was no significant difference in ORR between the two groups (90.3% vs. 87.1%, P=0.746). Subgroup analysis revealed that among the patients with hormone receptor-positive tumors, there were no significant differences in pCR rate (6.3% vs. 7.7%, P=0.852) or ORR (87.5% vs. 82.1%, P=0.839) between the goserelin and chemotherapy groups. Among the patients with hormone receptor-negative tumors, there were also no significant differences in pCR rate (53.3% vs. 56.5%, P=0.847) or ORR (93.3% vs. 95.7%, P=0.975) between the two groups. One year after the completion of chemotherapy, the incidence of chemotherapy-induced amenorrhea (CIA) was significantly lower in the goserelin group compared with the chemotherapy group (9.5% vs. 33.3%, P=0.036). Conclusion: For young breast cancer patients with clinical stages of ⅡA~ⅢC, there was no statistical difference in pCR rate and ORR whether or not using goserelin during NAC. However, it is still necessary to expand the sample size and carry out a longer follow-up to evaluate the effect of goserelin on the long-term survival of young patients.

Objective: To evaluate the efficacy and safety of dupilumab in the treatment of atopic dermatitis in the elderly. Methods: In this study, elderly patients with atopic dermatitis treated with dupilumab for at least 16 weeks in the Department of Dermatology and Venereology of Beijing Anzhen Hospital from January 2021 to October 2023 were retrospectively collected. Clinical indicators were compared before, during and after treatment, including pruritus numerical rating score (PNRS), eczema area and severity index (EASI), dermatology life quality index (DLQI) score, and the incidence of adverse events was recorded. The expression of interferon γ (IFN-γ), interleukin-4 (IL-4) and interleukin-6 (IL-6) in peripheral blood were compared before treatment and after 16 weeks of treatment. Results: A total of 90 elder patients with atopic dermatitis were included, EASI, PNRS and DLQI scores all showed a gradual downward trend during the treatment period, which was manifested as a rapid decline in the first 4 weeks after starting treatment, and then the decline gradually leveled off. The results of point-to-point comparison showed that EASI, PNRS and DLQI scores in 4 weeks after treatment were significantly lower than those before treatment (P < 0.001); In the 16th week after treatment, the scores of the above therapeutic indicators were further reduced, and the difference was statistically significant compared with the 4th week (P < 0.01); The EASI score was significantly lower at each time point than the previous time point, indicating that the patients' skin lesions continued to improve significantly. The overall efficacy of dupliumab was evaluated. After 4 weeks of treatment, 62.89% of patients achieved EASI-50 (EASI score decreased by ≥50%), and 74.4% of patients' DLQI score decreased by ≥4 points. After 16 weeks of treatment, 57.8% of the patients achieved EASI-75, 32.2% achieved EASI-90, and the PNRS and DLQI scores of all the patients decreased by ≥4 points. After 16 weeks of treatment, the expression levels of IL-4 and IL-6 were (31.62±6.23) ng/L and (14.36±2.25) ng/L, respectively, which were significantly lower than those before treatment (P < 0.001), and the expression level of IFN-γ was (15.37±3.14) ng/L, which was higher than before treatment (P < 0.001).The main adverse reactions were conjunctivitis (2 cases), injection site reaction (3 cases) and multiple bacterial folliculitis of the back (2 cases), which could be alleviated by symptomatic treatment, and no serious adverse reactions occurred. Conclusion: Dupilumab has shown good efficacy in the treatment of elderly atopic dermatitis, which can effectively improve clinical symptoms such as itching and skin lesions, improve the quality of life of patients, and no serious adverse reactions occurred during treatment, so it is safe and worthy of clinical promotion.

Objective: To precise classify sacral meningeal cysts, effective guide minimally invasive neurosurgery and postoperative personalized rehabilitation by multiple dimensions radiographic reconstruction MRI. Methods: From March to December 2021, based on the original 3D-fast imaging employing steadystate acquisition (FIESTA) scanning sequence, 92 patients with sacral meningeal cysts were pre-operatively evaluated by multiple dimensional reconstruction MRI. The shape of nerve root and the leakage of cyst were reconstructed according to the direction of nerve root or leakage track showed on original MRI scans. Sacral canal cysts were accurately classified as including nerve root and without nerve root, so as to accurately design the incision of skin and formulate corresponding open range of the posterior wall of the sacral canal. Under the microscope intraoperation, the shape of the nerve roots inside cysts or leakage track of the cysts without nerve roots were verified and explored. After the reinforcement and shaping operation, several reexaminations of multiple dimensional reconstruction MRI were performed to understand the deformation of the nerve root and hydrops in the operation cavity, so as to formulate a persona-lized rehabilitation plan for the patients. Results: Among the 92 patients with sacral mengingeal cyst, 58 (63.0%) cysts with nerve root cyst, 29 (31.5%) cysts without nerve root cyst, and 5 (5.4%) cysts with mixed sacral canal cyst. In 58 patients with nerve root cysts, the accuracy of preoperative clinical classification on MRI image reached 96.6% (56/58) through confirmation by operating microscope. Only 2 cases of large single cyst with nerve root on the head of cyst were mistaken for without nerve root type. In 29 patients with sacral cyst without nerve root, the accuracy of preoperative image reached 100% through confirmation by operating microscope. The accuracy of judging the internal nerve root and leakage of 12 cases with recurrent sacral cyst was also 100%. Two cases of delayed postoperative hydrops were found one month after operation. After rehabilitation treatment by moxibustion and bathing, the hydrops disappeared 4-6 months after operation. Conclusion: Multiple dimensional reconstruction MRI can precisely make clinical classification of sacral meningeal cysts before operation, guide minimally invasive neurosurgery effectively, and improve the rehabilitation effect.

Objective: To investigate the biocompatibility of porous WE43 magnesium alloy scaffolds manufactured by 3D printing technology and to observe its effect in treating femoral defects in New Zealand white rabbits. Methods: In vitro cytotoxicity test was performed using bone marrow mesenchymal stem cells from Sprague Dawley (S-D) rats. According to the different culture media, the cells were divided into 100% extract group, 50% extract group, 10% extract group and control group. After culturing for 1, 3 and 7 days, the cell activity of each group was determined by cell counting kit-8 (CCK-8). In the in vivo experiment, 3.0-3.5 kg New Zealand white rabbits were randomly divided into three groups: Experimental group, bone cement group and blank group, with 9 rabbits in each group. Each rabbit underwent surgery on the left lateral femoral condyle, and a bone defect with a diameter of 5 mm and a depth of 6 mm was created using a bone drill. The experimental group was implanted with WE43 magnesium alloy scaffolds, the bone cement group was implanted with calcium sulfate bone cement, and the blank group was not implanted. Then 4, 8 and 12 weeks after surgery, 3 rabbits in each group were euthanized by carbon dioxide anesthesia, and the femur and important internal organs were sampled. Micro-computed tomography (Micro-CT) scanning was performed on the left lateral femoral condyle. Sections of important internal organs were prepared and stained with hematoxylin-eosin (HE). Hard tissue sections were made from the left lateral femoral condyle and stained with methylene blue acid fuchsin and observed under a microscope. Results: In the cytotoxicity test, the cell survival rate in the 100% extract group was higher than that in the control group (140.56% vs. 100.00%, P < 0.05) on 1 day of culture; there was no statistically significant difference (P>0.05) in cell survival rate among the groups on 3 days of culture; the cell survival rate in the 100% extract group was lower than that in the control group (68.64% vs. 100.00%, P < 0.05) on 7 days of culture. Micro-CT scanning in the in vivo experiment found that most of the scaffolds in the experimental group had been degraded in 4 weeks, with very few high-density scaffolds remaining. In 12 weeks, there was no obvious stent outline. In 4 weeks, a certain amount of gas was generated around the WE43 magnesium alloy scaffold, and the gas was significantly reduced from 8 to 12 weeks. Hard tissue sections showed that a certain amount of extracellular matrix and osteoid were generated around the scaffolds in the experimental group in 4 weeks. In the bone cement group, most of the calcium sulfate bone cement had been degraded. In 8 weeks, the osteoid around the scaffold and its degradation products in the experimental group increased significantly. In 12 weeks, new bone was in contact with the scaffold around the scaffold in the experimental group. There was less new bone in the bone cement group and the blank group. Conclusion: The porous WE43 magnesium alloy scaffold fabricated by 3D printing process has good biocompatibility and good osteogenic properties, and has the potential to become a new material for repairing bone defects.

Objective: To investigate the current status of kinesiophobia after lumbar fusion surgery in patients with lumbar disc herniation (LDH) and to analyze its influencing factors. Methods: A total of 489 LDH patients who underwent lumbar fusion surgery in our hospital from January 2021 to December 2022 and effectively filled out the tampa scale for kinesiophobia (TSK) and other questionnaires on the first day after surgery were collected as the study subjects, the current status of kinesiophobia in LDH patients after lumbar fusion surgery were investigated using the TSK. The LDH patients were grouped into a kinesiophobia group (n=221) and a non kinesiophobia group (n=268) based on whether there was kinesiophobia after lumbar fusion surgery. The self-designed general data questionnaires were used to collect data, and Logistic regression was applied to analyze independent risk factors for kinesiophobia after lumbar fusion surgery in the LDH patients. Results: In the study, 221 out of the 489 LDH patients (45.19%) had kinesiophobia after lumbar fusion surgery. Univariate analysis showed that there were statistically significant differences between the phobic group and the non phobic group in terms of gender, education level, course of disease, whether there was hypoproteinemia, pain level, self-efficacy, social support, whether there was anxiety, and whether there was depression (P < 0.05). There were no statistically significant differences in terms of age, body mass index, monthly family income, marital status, residence, medical expense payment form, whether there was hypertension, whether there was diabetes, whether there was cardiovascular and cerebrovascular disease, whether there was respiratory disease, whether there was surgery experience, whether there was anemia, work conditions, and responsibility segments (P>0.05). Male (95%CI: 3.289-10.586, P < 0.001), education level below undergraduate level (95%CI: 6.533-45.162, P < 0.001), severe pain (95%CI: 10.348-72.025, P < 0.001), moderate pain (95%CI: 6.247-37.787, P < 0.001), low self-efficacy (95%CI: 4.238-15.095, P < 0.001), and medium self-efficacy (95%CI: 2.804-8.643, P < 0.001) were influencing factors for kinesiophobia after lumbar fusion surgery in the patients with LDH (P < 0.05). Conclusion: The incidence of kinesiophobia after lumbar fusion surgery in patients with LDH is high, and its influencing factors include gender, education level, pain level, and self-efficacy.

Objective: To explore the feasibility of establishing a temporary trauma team led by trauma experts in primary hospitals for disaster medical rescue. Methods: In the coal mine flooding accident in Xiaoyi City, Shanxi Province on December 15, 2021, according to the local emergency plan and the characteristics of the accident, the trauma experts trained the medical staff from the local primary hospital on advanced trauma life support (ATLS) and damage control surgery (DCS) in the short time interval between the occurrence of the mine disaster and the admission of medical staff to the disaster scene. A temporary trauma team composed of trauma experts, ATLS team, and DCS team was formed to provide early diagnosis and treatment for survivors before and in the hospital. Results: The miners were found on the 36th hour of the disaster. All 22 miners were male, and 2 died underground. Another 20 people were rescued 39－43 hours after the disaster, with a median age of 48 years (34-57 years). All the survivors suffered from hypothermia, dehydration, maceration of feet and other injuries. There were 18 cases of acute inhalation tracheobronchitis, 14 cases of electrolyte acid-base disturbance, 6 cases of trunk contusion, 1 case of psoas major hematoma, and 1 case of lower extremity hematoma. Deep vein thrombosis was in 4 cases. The ATLS team focused on injury assessment, rewarming and rehydration within 50－60 minutes before admission, and completed auxiliary examinations within 2 hours after admission to clarify the diagnosis. The DCS team evaluated 6 patients with mechanical blunt trunk injury and excluded the indication of emergency surgery. The trauma experts conducted the whole process of supervision and quality control of disaster rescue. The positive rate of capillary refill test in the all survivors at the third hour of admission was significantly lower than that immediately after being rescued (75.0% vs. 15.0%, P=0.000 3), and they were discharged 4－7 days after admission. Conclusion: Under the leadership of trauma experts and relying on the medical staff of primary hospitals, it is feasible to establish and train a temporary trauma team with ATLS and DCS functions to participate in the medical rescue of disasters, which is in line with the current national conditions of China.

Objective: To explore the impact factors and the clinical significance of the urination intermittences in benign prostatic hyperplasia (BPH) patients. Methods: A retrospective study was performed in BPH patients who underwent urodynamic studies in Beijing Jishuitan Hospital form January 2016 to June 2021. The patients were aged 45 to 84 years with a median age of 63 years, and all the patients had no previous history of neurological disease and had no positive findings in neurological examinations. All the patients had free uroflometry followed by urethral catheterization and urodynamic tests. The voiding work of bladder was calculated using the detrusor power curve method, and the voiding power of bladder and the voiding energy consumption were also calculated. The frequency of urination intermittences generated in uroflometry was also recorded and the patients were divided into different groups according to it. The detrusor pressure at maximal flow rate (P_detQ_max), the maximal flow rate (Q_max), the bladder contractile index (BCI), the bladder outlet obstruction index (BOOI), the voiding work, the voiding power, and the voiding energy consumption were compared among the different groups. Multiva-riate analyses associated with presence of urination intermittences were performed using step-wise Logistic regressions. Results: There were 272 patients included in this study, of whom, 179 had no urination intermittence (group A), 46 had urination intermittence for only one time (group B), 22 had urination intermittence for two times (group C), and 25 had urination intermittence for three times and more (group D). The BCI were 113.4±28.2, 101.0±30.2, 83.3±30.2, 81.0±30.5 in groups A, B, C, and D, respectively; The voiding power were (29.2±14.8) mW, (16.4±9.6) mW, (14.5±7.1) mW, (8.5±5.0) mW in groups A, B, C, and D, respectively, and the differences were significant (P < 0.05). The BOOI were 41.6±29.3, 46.4±31.0, 41.4±29.0, 42.7±22.8 in groups A, B, C, and D, respectively; The voiding energy consumption were (5.41±2.21) J/L, (4.83±2.31) J/L, (5.02±2.54) J/L, (4.39±2.03) J/L in groups A, B, C, and D, respectively, and the differences were insignificant (P>0.05). Among the patients, 179 cases were negative in presence of urination intermittences and 93 cases were positive. Step-wise Logistic regression analysis showed that bladder power (OR=0.814, 95%CI: 0.765-0.866, P < 0.001), BCI (OR=1.023, 95%CI: 1.008-1.038, P=0.003), and bladder work (OR=2.232, 95%CI: 1.191-4.184, P=0.012) were independent risk factors for urination intermittences in the BPH patients. Conclusion: The presence of urination intermittences in the BPH patients was mainly influenced by bladder contractile functions, and was irrelevant to the degree of bladder outlet obstruction. The increase of frequency of urination intermittences seemed to be a sign of the decrease of the bladder contractile functions in the BPH patients.

Objective: To evaluate the clinical outcomes and explore the application of partial sialoadenectomy for the treatment of benign tumors in the submandibular gland (SMG). Methods: Patients with pleomorphic adenoma of the SMG who underwent surgical treatment in the Department of Oral and Maxillofacial Surgery, Peking University Shenzhen Hospital, from October 2017 to February 2021, were enrolled and assessed in the follow-up. Fifteen patients underwent partial sialoadenectomy (PS group), and 18 patients underwent total sialoadenectomy (TS group). Postoperative salivary secretion, degree of dry mouth, appearance changes of the face and neck, nerve damage, and tumor recurrence were compared between the groups. The volume of the glands on the operated and contralateral sides of the patients in the PS group, the saliva flow rate, and their correlations, were also analyzed. Results: There was no recurrence during the follow-up period. The whole saliva flow rate at rest in the PS group was higher than that in the TS group [(2.15±1.10) g/5 min vs. (1.35±0.97) g/5 min, t=2.208, P=0.035)], while the stimulated saliva flow rate was not significantly different. The objective feeling of dry mouth, evaluated by visual analogue scale (VAS) score, was more obvious in the TS group than in the PS group (Z=-2.244, P=0.025). In the PS group, the resting saliva flow rate of the SMG on the operated side was lower than that on the contralateral side of the same patient [(0.92±0.40) g/5 min vs. (1.18±0.40) g/5 min, t=-2.821, P=0.014], however, in the cases whose remaining SMG was more than 80% of the contralateral side, the saliva flow rate of both sides was not significantly different (t=-0.027, P=0.980). There was no significant difference in the saliva flow rate per unit volume of the gland on either side (t=-0.015, P=0.989), and the saliva flow rate of the operated SMG was positively correlated with the volume of the remaining gland (r=0.750, P=0.012). The VAS scores for neck deformity were not significantly different between the two groups (t=-0.997, P=0.319). No symptoms of nerve injury occurred in either group. Conclusion: Partial sialoadenectomy in the SMG can safely remove benign tumors while preserving glandular secretory function, with fewer complications and improved quality of life.

Objective: To explore the effects of two methods of smear layer removal on the surface properties of dentin. Methods: Sixty extracted sound third molars were collected in this study, and were prepared as uniform dentin specimens with smear layer. All specimens were randomly divided into three groups: Control group, ultrasonic treatment (UT) group and etched treatment (ET) group. Scanning electron microscope (SEM) were used to observe the surface micromorphology of all three groups. Then, the surface elements, mineral phases and functional groups were analyzed by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and flourier transformed infrared spectrometer (FTIR) respectively. The mechanical properties, hydrophilicity and biocompatibility were also further evaluated. Results: It was revealed that dentin tubules of UT and ET groups were exposed, but lots of dentin debris piled up on the surface of the control one which covered up dentin tubules on the surface. The EDX results should that the weaker peak value of calcium and phosphorus in ET group than control and UT groups. Characteristic peaks of hydroxyapatite could be seen by XRD in all of the three groups, but lower distinctive peaks of amide Ⅰ, Ⅱ and Ⅲ bands of collagen of the dentin surface in control group than in ET and UT groups. The microhardness results showed that ET group was lower than control and UT groups, the difference was significant (P < 0.05). Better hydrophilicity of ET group was investigated (P < 0.05) than control group and UT group. Cells could be observed to adhere normally to dentin surface of each group which meant that all of the three groups had good biocompatibility. Conclusion: Both UT and ET could effectively remove the smear layer on the surface of dentin and had no adverse effect of the dentin micromorphology and biocompatibility. The ultrasonic removal of the smear layer did not influence the mineral structure, hydrophilicity and mechanical properties of dentin surface. Although ET can effectively improve the hydrophilicity of dentin but decreased mechanical properties and the content of calcium and phosphorus.

Objective: To observe the long-term health condition of the single-tooth dental implant at the first molar site, and to evaluate the related factors affecting the peri-implant health. Methods: In this study, 82 patients who were treated in the Second Clinical Division, Peking University School and Hos-pital of Stomatology from January 2008 to December 2020 were enrolled. Peri-implant tissue conditions were assessed by clinical and radiographic examination. The peri-implant probing depth (PPD), modified sulcus bleeding index (mSBI), modified plaque index (mPLI) and papilla index (PI) were recorded for 278 implants. The X-ray analysis included the restoration emergence angle (REA), the clinical crown-implant ratio (cC/I), the horizontal tooth-implant distance (HTID), the contact point level (CPL) and the embrasure surface area (ESA), etc. Kruskal-Wallis rank sum test and generalized estimation equation were used for statistical analysis. Results: The average age of the patients was (40.2±9.5) years (19 to 84 years), with 33 males and 49 females. The follow-up time was (4.9±3.3) years (1 to 10 years). According to the diagnostic criteria in 2018, the prevalence of peri-implantitis in this study was 14.03% on the implant level and 21.95% on the patient level. The peri-implant health rate was 19.06% on the implant level and 18.29% on the patient level. The prevalence of peri-implant mucositis was 66.91% on the implant level and 59.75% on the patient level. At the baseline, there were statistically significant differences between the peri-implant health group and peri-implantitis group in PPD, distal HTID and mesial/distal CPL, cC/I (P < 0.05), while there was no statistically significant difference in mSBI, mPLI, PI, mesial HTID, mesial/distal REA and mesial/distal ESA between the two groups. Among the differences between follow-up and baseline, there were statistically significant dif-ferences between the two groups in PPD, mesial/distal HTID, mesial/distal CPL and mesial/distal ESA (P < 0.05). Generalized estimation equation showed that PPD, mesial/distal HTID, mesial CPL, and mesial ESA had significant positive correlations with the risk of peri-implantitis in the difference between baseline and follow-up. Conclusion: Based on the results of this study, the peri-implant health rate is still unsatisfied, and the PPD, HTID, CPL, ESA may be related to the long-term health of the implant.

Objective: To compare the registration accuracy of cone beam computed tomography (CBCT) images while registering to virtual craniodentofacial patients based on soft tissue and the dentition registration method. Methods: Virtual dentofacial patients out of 13 selected participants who needed CBCT scanning were established by impression with a registered-block impression (RBI) based on digital dental images, three-dimensional (3D) facial images and maxillofacial CBCT images. CBCT images were processed in the Mimics software program, establishing the craniofacial virtual patients based on CBCT images (CCTs). Registration between virtual patients from RBI and CCT, using the soft tissue in lower half face (STE) and dentition (DTN) as the reference area, respectively, forming two kinds of virtual craniofacial patients based on digital dental images, 3D facial images and skeletal images of CBCT (hiding the soft tissue and dental casts from CBCT). Three-dimensional deviation analysis was performed in the upper half face and lower half face of facial images from CBCT between two kinds of virtual craniodentofacial patients and compared with 3D facial images from RBI and recorded as root mean square error (RMSE). Paired-t test was used to compare the deviations of RMSEs between the upper and lower half of the face and the upper half of the face of facial images from CCT, respectively, between the two kinds of virtual craniodentofacial patients based on STE and DTN methods. Results: Paired-t tests showed that there was no statistically significant difference between the upper and lower half faces of facial images from CCT between STE and DTN (P>0.05), but the deviation of RMSEs of the upper half face of facial images from CCT in STE was smaller than those in DTN [(1.696±0.420) mm vs. (1.752±0.424) mm, P < 0.01]. Conclusion: The registration accuracy of CBCT registered in virtual craniodentofacial patients using soft tissue as the reference area was higher.

Objective: To propose a new protocol for personalized mandibular reconstruction assisted by three-dimensional (3D) retrieval model based on fully connected neural network (FCNN) and a database of mandibles, and to verify clinical feasibility of the protocol. Methods: A database of mandibles of 300 normal northern Chinese Han people was established. On the basis of cephalometry, the mandible landmarks with good stability were further screened. Mandibular landmarks were selected and geometric features of the mandible were extracted. A 3D retrieval algorithm was developed, which could retrieve the mandible most similar to a given mandible from the database. A FCNN was built to train the algorithm to improve accuracy of the 3D retrieval model. Using Geomagic Control 2014 software, matching accuracy of the 3D retrieval model was based on aforementioned mandible database and algorithm. From December 2019 to March 2021, a total of 5 patients underwent personalized mandibular reconstruction assisted by a 3D retrieval model based on mandible database and FCNN in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The most similar mandible was retrieved from mandible database through 3D retrieval algorithm. It was used to restore the premorbid morphology of defect area and guide mandibular reconstruction. For the 5 patients, mandible was reconstructed with iliac flap. Virtual surgical plan was transformed using individual surgical guides. Results: Through screening, mandibular landmarks with high reproducibility and stability were identified and composed of mandibular landmarker protocols. After training, the average deviation between most similar mandible retrieved from the 300-case mandible database through 3D retrieval model based on FCNN and given mandible was (1.77±0.44) mm. And the root-mean-square deviation between the most similar mandible retrieved from the database and given mandible was (2.58±0.86) mm. The mandibular reconstruction surgery was successful in all the 5 patients. Their facial symmetry and occlusion were restored. All the patients were satisfied with postoperative appearance. The mean deviation between postoperative mandible and preoperative design was (0.98±0.17) mm. The area with a deviation ≤1 mm accounted for 61.34%±14. 13%, ≤2 mm accounted for 83.82%±7.35%, and ≤3 mm accounted for 93.94%± 2.87%. Conclusion: The personalized mandibular reconstruction assisted by 3D retrieval model based on the 300-case mandible database and FCNN is feasible clinically.

Objective: To evaluate the filling quality of single cone obturation in root canal model with irregular structure (Hus&Kim Ⅴ, Yin Ⅱ-type isthmus) which established by 3D printing technology using slices and radiographic methods, in order to provide reference for clinical practice. Methods: (1) Extracted fresh premolars with Hus&Kim Ⅴ and Yin-type Ⅱ isthmus were collected and scanned by cone-beam computed tomography (CBCT), then standard root canal models were designed and printed. Rhodamine B staining and bias fitting were used to verify the availability of the models. (2) 30 root canal models were randomly divided into 3 groups according to different filling methods (n=10). Control group: vertical compaction obturation; Experimental group 1: single cone obturation with 0.06-taper cone (30#); Experimental group 2: single cone obturation with 0.04-taper cone (35#), GuttaFlow 2 as canal sealers. Slices were taken at 2, 4, 6, and 8 mm from the root apex in the direction perpendicular to the long axis of the root and observed under a stereomicroscope to calculate the percentage of filling area (PAV), percentage of gutta-percha-filled area (PGFA), percentage of sealer filled area (PSFA). (3) On the basis of the above results, two groups (n=4) were selected to further analyze the filling quality by micro-computed tomography (Micro-CT), the filling volume of main root canal and the isthmus were obtained, and the percentage of filling volume (PFV) was calculated. Two-way ANOVA was used to evaluate the differences between the groups, and Tukey' s multiple comparison was used to compare the data between the groups and within the groups. Results: (1) Rhodamine B staining solution could overflow the apical foramen, and the main root canal system and the isthmus area were stained, showed no remnants of support material. The 3D standard deviation of the printed model data was 0.03 mm, and the average fitting distance was 0.02 mm. (2) The PFA of the two experimental groups were both significantly lower than that of the control group (F=45.04, P < 0.01). There was no statistical difference of the PFA at apical 2 and 4 mm between the two experimental groups (P>0.01), but at the middle and coronal portions of the root canal (6, 8 mm), the PFA of the experimental group 1 was higher than that of the experimental group 2 (P < 0.01). PFA in the apical 2, 4 mm of the two experimental groups were both lower than that in the middle and coronal portions 6, 8 mm of the canal (P < 0.01). There was no difference in the PGFA and PSFA between the two experimental groups at the apical 2, 4 mm (F=2.383, P>0.01). (3) The results of Micro-CT showed that the PFV of the experimental group 1 was statistically different with the control group (F=47.33, P < 0.01). The PFV of the experimental group 1 was 54.33%±4.35% in the isthmus and 78.31%±4.21% in the main root canal, which were both lower than the PFV of the control group of 76.48%±4.89% (isthmus) and 86.90%±3.29% (main root canal, P < 0.01). The PFV of the main root canal in the experimental group 1 was higher than that in the isthmus (P < 0.01), while there was no difference between the isthmus and the main root canal in the control group (P>0.01). Conclusion: In the irregular root canal structure with isthmus, using large-taper gutta-percha can improve the filling quality of the middle and upper part of the canal, but the percentage of filling volume in the isthmus is lower than that of the main canal, and more technical improvements are needed.

Objective: To establish a three-dimensional finite element model of a digital wire loop space maintainer for the mandible and primary tooth loss, in order to investigate the stress, deformation, and shear force experienced by patients with the loss of the second primary molar when wearing the wire loop space maintainer. Methods: Cone beam computed tomography (CBCT) scans were performed on the patients to create a digital model of the mandible with the absence of the second primary molar using Mimics 21.0 software. A digital model integrating the crown's retention and the wire loop structure of the full crown and ring wire loop space maintainer was constructed using pediatric space maintainer design software, utilizing three different materials: cobalt-chromium alloy, polyether ether ketone (PEEK), and titanium alloy. In ANSYS Work Beach 2023 R2 software, vertical loads of 70 N, tilted 45° along the long axis of the tooth loads of 70 N, and a 10 N load on the surface of the wire loop were applied to the occlusal surfaces of models 46 and 84, simulating centric and lateral occlusions during chewing with the wire loop space maintainer in place. The stress states of the wire loop space maintainer and supporting teeth were analyzed. Results: Under various loading conditions, the maximum principal stress of the ring wire loop space maintainer was significantly lower than that of the full crown. Stress contour maps indicated that the peak of the maximum principal stress occurred at the junction of the wire loop and crown structure, indicating that this area was more susceptible to fracture. The ring wire loop space maintainer made from PEEK material exhibited the lowest maximum shear stress on the internal organizational surfaces, with equivalent stresses of 23.18 MPa and 36.35 MPa for models 46 and 84, respectively. Stress contour maps demonstrated that the maximum stress on tooth 46 was located at its mesial, while the maximum stress on tooth 84 was situated near the root area on its distal, in contact with the wire loop space maintainer. Conclusion: In cases of second primary molar loss, wearing the digital ring wire loop space maintainer can effectively distribute stress, and the ring wire loop space maintainer made from PEEK material reduces the stress experienced by supporting teeth to some extent, demonstrating its superiority in clinical application.

Objective: To standardize the operative procedure for tissue-engineered cartilage repair, by demonstrating surgical technique of arthroscopic implantation of decalcified cortex-cancellous bone scaffolds, and summarizing the surgical experience of the sports medicine department team at Peking University Third Hospital. Methods: This article elaborates on surgical techniques and skills, focusing on the unabridged implantation technology and surgical procedure of decalcified cortex-cancellous bone scaffolds under arthroscopy: First, the patient was placed in the supine position. After anesthesia had been established, the surgeon established an arthroscope and explored the damaged area under the scope. After confirming the size and location of the injury site, the surgeon cleaned the damaged cartilage, and also trimmed the edges of the cartilage to ensure that the cut surface was smooth and stable. the surgeon performed the micro-fracture surgery in the area of cartilage injury, and then measured the size of the injured area under the scope. Next, the surgeon manually trimmed the tissue-engineered scaffold based on the measurements taken under the arthroscope, and then directly implanted the scaffold using a sleeve. A honeycomb-shaped fixator was used to implant absorbable nails to fix the scaffold. After the scaffold was installed, the knee was repeatedly flexed and extended for 10-20 times to ensure stability and range of motion. Finally, the arthroscope was withdrawn and the wound was closed. Results: Decalcified cortex-cancellous bone scaffolds possessed unparalleled advantages over synthetic materials in terms of morphology and biomechanics. The cancellous bone part of the scaffold provided a three-dimensional, porous space for cell growth, while the cortical bone part offered the necessary mechanical strength. The surgery was performed entirely under arthroscopy to minimize invasiveness to the patient. Absorbable pins were used for fixation to ensure the stability of the scaffold. This technique could effectively improve the prognosis of the patients with cartilage injuries and standardized the surgical procedures for arthroscopic tissue-engineered scaffold operations in the patients with cartilage damage. Conclusion: With the standard arthroscopic tissue-engineered scaffold repair technique, it is possible to successfully repair damaged cartilage, alleviate symptoms in the short term, and provide a more ideal long-term prognosis. The author and their team explain the surgical procedures for tissue-engineered scaffolds under arthroscopy, with the aim of guiding future clinical practice.

Osteonecrosis of the mandible is also called avascular necrosis of the jaw, and it is a rare complication of bisphosphonates. It is characterized with pain, swelling, exposure of bone, local infection and pathologic fractures of the jaw. With the widespread usage of bisphosphonates in bone metastasis of malignant tumors and osteoporosis, this rare complication has received more attention in recent years. Here, we reported a case of bisphosphonates-related osteonecrosis of the jaw (BRONJ) caused by intravenous zoledronic acid for osteoporosis. A 62-year-old female patient with 7-year history of Sjögren's syndrome and 3-year history of osteoporosis developed BRONJ after 3-year treatment of zoledronic acid. Two months before she went to the Peking University International Hospital, she visited the dentist for periodontal purulent secretion and extracted one tooth from the right mandible. However, the condition was not improved and she felt persistent pain and swelling in the right mandible. Hence, she received repeated root curettage, but there was no improvement. Finally, she was diagnosed with osteonecrosis of the mandible based on the digital volume tomography scan, which showed right mandibular osteonecrosis bone destruction. She underwent surgical debridement of the necrotic bone and administered intravenous antibio-tics at the Peking University International Hospital. Histopathological analysis of the bone biopsy further confirmed the diagnosis of BRONJ. Her condition was improved successfully during a 3-year follow-up. Osteonecrosis of the mandible become more common with the increased use of bisphosphonates. Recent study has reported that osteonecrosis of the mandible is more likely to occur in patients with Sjögren's syndrome. In addition, age, long-term and irregular administration of glucocorticoids, irregular oral examination and treatment also might be the risk factors in the pathogenesis of osteonecrosis of the mandible. For the elder osteoporosis patients who would receive or had received bisphosphonate-related drugs, oral health status and the disease states associated with necrosis of the mandible such as Sjögren's syndrome should be comprehensively measured and fully evaluated during the whole process. Furthermore, to better understand and prevent or reduce the occurrence of this complication, we reviewed the patho-genesis, diagnosis, treatment, and prevention of BRONJ.

To improve clinicians' understanding, and to explore the diagnosis and treatment of pregnancy complicated with patent urachus. The clinical symptoms, ultrasound images, and delivery outcome of the pregnancy complicated with patent urachus were reported, and the literature was reviewed. The patient had umbilical leakage as a young child occasionally, the symptom of leakage was not obvious after she was 10 years old, and there was no asymptomatic before pregnancy and in the first and second trimesters. Umbilical leakage was present at gestational 33 weeks, and ultrasound showned a tubular structure (0.7 cm in width) was connected between the top of the bladder and the umbilicus, and there was anechoic areas inside. The pregnancy complicated with patent urachus was diagnosed. The patient was checked regularly, and kept the umbilicus clean and dry. Premature rupture of membranes occured at gestational 39 weeks 4 days. The patient was admitted to the obstetrics department, and she deliveried finally. After delivery, the symptoms of umbilical leakage urine relieved, and an elective resection of abnormal urachus was planned. The patent urachus creates a tube connection between the umbilicus and the anterosuperior wall of the bladder, it was termed an median umbilical ligament at birth as usual, which still communicated with the bladder after birth. The main clinical manifestations were umbilical leak and infection, which were the main diagnostic basis. Ultrasound, CT and MRI were important auxi-liary examination methods.The patients with symptoms in the neonatal and early childhood period were managed actively and had the potential for self resolution, especially for the children younger than 1 year. Therefore, patients under 1 year of age were offered surgery only if they had recurrent infections or failed to selfresolve. It is recommended to remove abnormal urachus before pregnancy for the women complica-ted with patent urachus. If the patent urachus was found during pregnancy, the umbilicus should be kept clean and dry to avoid infection. The pregnancy complicated with patient urachus is not contraindicated to vaginal delivery.

Renal autotransplantation (RA) offers significant technical advantages for the management of certain complex renal vascular diseases, such as complex renal aneurysms and renal artery malformations. This report describes a case of a 5-year-old child with a complex left renal artery aneurysm combined with multiple aneurysms. The child was admitted to Peking University People's Hospital in December 2023 due to a one-year history of intermittent abdominal pain, with an abdominal mass detected in the past month. Computed tomography angiography(CTA) revealed multiple vascular anomalies, including: (1) a left renal artery aneurysm, (2) an abdominal aortic aneurysm, and (3) a right iliac artery aneurysm. After a comprehensive evaluation of these findings, the surgical team developed a treatment plan that involved the excision of the left renal artery aneurysm, autotransplantation of the left kidney, and resection of the abdominal aortic aneurysm with an artificial vascular catheterization. During surgery, it was discovered that the left renal artery anatomy was highly complex. The artery had two primary branches, along with an additional polar artery located at the lower pole. The aneurysm was identified at the distal end of the renal artery trunk, with a pronounced bulging at the intersection between the main renal artery trunk and its secondary branches. Due to these structural complexities, the team decided to use an ex vivo surgical approach to repair the aneurysm. Ex vivo repair involves temporarily removing the kidney from the body to repair the renal artery aneurysm with enhanced precision, enabling the surgical team to meticulously reconstruct the complex vascular architecture without the constraints of in vivo manipulation. The ex vivo repair of the renal artery aneurysm was successful, allowing for accurate vascular reconstruction and avoiding potential intraoperative complications. Following the reconstruction, the kidney was autotransplanted back into the child's body, and blood flow was effectively restored to the organ. The therapeutic outcome was excellent, with the child experiencing no postoperative complications. The patient recovered well and was discharged from the hospital in stable condition. This case underscores the value of renal autotransplantation combined with ex vivo repair for pediatric patients with complicated renal artery aneurysms. Through this report, we aim to provide insights and considerations for the surgical treatment of similar cases in children with complex renal vascular anatomy.

The oral glucose growth hormone suppression test is commonly used in the clinical diagnosis of acromegaly, but its results can be influenced by a variety of factors. This case report discusses a patient with a pituitary tumor and concurrent liver cirrhosis, highlighting the complexities in interpreting test results under such conditions. The patient, a 54-year-old male, presented with blurred vision as his primary complaint. Notably, the physical examination revealed no changes in facial features, no enlargement of hands or feet, and no other symptoms typically associated with acromegaly, which might otherwise suggest excessive growth hormone activity. Magnetic Resonance Imaging (MRI) of the pituitary gland indicated that the gland was within normal size parameters, but a small low-intensity lesion mea-suring approximately 3 mm×2 mm identified. This finding was consistent with a pituitary microadenoma. The patient's fasting growth hormone levels were significantly elevated at 8.470 μg/L, compared with the normal range of less than 2.47 μg/L. Conversely, fasting insulin-like growth factor-1 (IGF-1) levels were notably low, recorded at 41 and 52 μg/L, whereas the normal range for a person of his age was between 87 and 234 μg/L. Other pituitary hormones, including those regulating the thyroid, adrenal cortex, and sex hormones, were found to be within normal ranges. Despite this, during the glucose growth hormone suppression test, an abnormal elevation of growth hormone was observed. To investigate further, the patient was administered branched-chain amino acids, and the suppression test was repeated. However, the abnormal elevation of growth hormone persisted, indicating a failure to normalize the response. Given the patient's lack of clinical signs typically associated with elevated growth hormone secretion, the history of liver cirrhosis became a significant consideration. The disparity between elevated growth hormone levels and reduced IGF-1 levels suggested that the pituitary lesion was a non-functional adenoma rather than a source of excess hormone production. Consequently, it was concluded that the abnormal response of growth hormone to the glucose suppression test was likely related to the patient's liver cirrhosis. In addition to chronic liver disease, various other conditions could influence the results of the oral glucose tolerance growth hormone suppression test. According to the literature, factors such as puberty, diabetes, anorexia nervosa, and protein malnutrition could also affect test outcomes. These conditions could cause similar abnormalities in growth hormone dynamics, complicating the diagnosis. Therefore, clinicians must be vigilant and consider these potential influences when interpreting test results.For an accurate diagnosis of acromegaly, it is essential to combine clinical symptoms, detailed medical history, and imaging studies. The presence of conditions like liver cirrhosis should prompt careful interpretation of the test results, ensuring that other contributing factors are not overlooked. This comprehensive approach is crucial to avoid misdiagnosis and to ensure that appropriate treatment strategies are implemented based on a thorough understanding of the patient's overall health status.

Sweet syndrome (acute febrile neutrophilic dermatosis) is a relatively rare inflammatory di-sease, which is characterized by the sudden appearance of tender erythematous skin lesions, often accompanied by pyrexia and elevated neutrophil count. The pathogenesis is not clear yet. Recently, multiple studies have found the association between Sweet syndrome and infections, autoimmune diseases, malignant tumors and the application of multiple drugs. According to different causes, Sweet syndrome can be divided into three types: classical (or idiopathic) Sweet syndrome, malignancy-associated Sweet syndrome and drug-induced Sweet syndrome. Classical Sweet syndrome usually presents in women between the age of 30 to 50 years and may be related to infection, inflammatory bowel disease, or pregnancy. The clinical symptoms typically respond promptly after corticosteroid therapy. The major diagnostic criteria of classical Sweet syndrome include sudden painful erythematous skin lesions, histopathologic evidence of a dense neutrophilic infiltrate without evidence of leukocytoclastic vasculitis; minor criteria include pyrexia over 38 ℃, association with hematologic or visceral malignancies, inflammatory diseases, pregnancy or preceded by infection, prompt response to systemic glucocorticoid or potassium iodide treatment, abnormal laboratory values (three of four: erythrocyte sedimentation rate >20 mm/h, positive C-reactive protein, >8.0×10⁹/L leukocytes, >70% neutrophils). The presence of both major criteria and two of the four minor criteria are required to diagnose classical Sweet syndrome. As for the malignancy-associated Sweet syndrome, skin lesions can be found precede, follow, or at the same time with the diagnosis of hematologic malignancy or a solid tumor. At present, ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) is commonly used as a positron emission tomography computed tomography (PET/CT) imaging agent for diagnosing and screening malignant tumors. Therefore, most of the case reports on the ¹⁸F-FDG PET/CT manifestations of Sweet syndrome are malignancy-associated. Even classical Sweet syndrome is often accompanied by inflammatory bowel disease, autoimmune diseases, etc. Therefore, for patients with suspected or confirmed Sweet syndrome, it is necessary to take ¹⁸F-FDG PET/CT examination to clarify the general condition, whether it is for patients with malignant signs such as elevated tumor markers values and weight loss, or for patients with classical Sweet syndrome to exclude underlying inflammatory diseases. ¹⁸F-FDG PET/CT is often able to detect the solid tumor early, and assess the degree of hematologic malignancy and inflammatory disease. This study reported a classical Sweet syndrome case associated with inflammatory bowel disease, which was confirmed with skin and intestinal histological examination. The clinical manifestations, laboratory values, ¹⁸F-FDG PET/CT manifestations of the patient related diseases were reported, which was to improve nuclear medicine physicians' understanding of Sweet syndrome. Early diagnosis and treatment can often achieve excellent clinical effect.