BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).

Objective·To determine hyaluronan(HA)expression in the endocrine-resistant microenvironment of estrogen receptor-positive(ER+)breast cancer and elucidate its impact on the acquired resistance.Methods·Chemiluminescent immunoassay was used to quantify HA levels in the culture supernatants of fulvestrant-resistant breast cancer cells.An immunofluorescence(IF)assay was performed to visualize the colocalization of CD44 and HA in MCF7/FulR cells.Using an established adaptive endocrine-resistant breast cancer mouse model,HA expression in resistant breast cancer tissues was assessed by immunohistochemistry(IHC)assay.Single-cell RNA sequencing(scRNA-seq)and RNA sequencing(RNA-seq)were conducted to examine transcriptomic profiles and alterations in HA-related genes in resistant breast cancer cells.Flow cytometry(FCM)was utilized to measure the proportion of CD44+CD24-cells in MCF7/FulR.The correlation between HA synthesis genes and cell stemness was investigated in clinical ER+breast cancers from GEO data sets.Hyaluronidase(HAase)treatment was applied to remove the"HA coat",and RT-qPCR and Western blotting analysis were carried out to monitor changes in stemness-related molecules.CCK-8 assays,flow cytometry(FCM),and Hoechst 33258 staining were performed to determine changes in apoptosis and fulvestrant efficiency after HAase treatment.Results·IF results revealed that compared with MCF7 cells,the"HA coat"on the surface of MCF7/FulR cells was significantly thickened.IHC demonstrated markedly increased HA retention in fulvestrant-resistant mouse breast cancer tissues.ScRNA-seq and RNA-seq analyses indicated elevated expression of stemness-related genes and HA synthesis-associated genes in fulvestrant-resistant breast cancer cells.Correlation analysis revealed a positive association between HA synthesis and cancer stemness in ER+breast cancer.IF and RT-qPCR results demonstrated that removing the HA coating from the surface of MCF7/FulR cells led to a significant reduction in the expression of stemness-related molecules;concurrently,CCK-8 assays,FCM analysis,and Hoechst 33258 staining revealed that"HA coat"clearance reduced MCF7/FulR'tolerance to fulvestrant and increased apoptosis.Conclusion·Endocrine-resistant breast cancer cells develop an enriched"HA coat",which promotes stemness in fulvestrant-resistant tumors.Disruption of this HA coat through HAase treatment effectively reduces cell stemness,induces apoptosis,and re-sensitizes breast cancer cells to fulvestrant.

Circular RNAs(circRNAs)are a class of closed-loop non-coding RNAs(ncRNAs)formed by head-to-tail covalent bonds.CircRNAs participate in the development of osteoarthritis by regulating extracellular matrix degrada-tion,inflammatory response and homeostasis of chondrocytes;It regulates the osteogenic differentiation of bone mar-row mesenchymal stem cells,the activity of bone microvascular endothelial cells and angiogenesis to affect femoral head necrosis;It regulates the differentiation of bone marrow stem cells,osteoblasts and osteoclasts to cause osteo-porosis and it affects the invasion,metastasis and drug resistance of osteosarcoma through different pathogenesis.CircRNAs are expected to become a new clinical diagnostic marker in the future.

Objective·To determine hyaluronan(HA)expression in the endocrine-resistant microenvironment of estrogen receptor-positive(ER+)breast cancer and elucidate its impact on the acquired resistance.Methods·Chemiluminescent immunoassay was used to quantify HA levels in the culture supernatants of fulvestrant-resistant breast cancer cells.An immunofluorescence(IF)assay was performed to visualize the colocalization of CD44 and HA in MCF7/FulR cells.Using an established adaptive endocrine-resistant breast cancer mouse model,HA expression in resistant breast cancer tissues was assessed by immunohistochemistry(IHC)assay.Single-cell RNA sequencing(scRNA-seq)and RNA sequencing(RNA-seq)were conducted to examine transcriptomic profiles and alterations in HA-related genes in resistant breast cancer cells.Flow cytometry(FCM)was utilized to measure the proportion of CD44+CD24-cells in MCF7/FulR.The correlation between HA synthesis genes and cell stemness was investigated in clinical ER+breast cancers from GEO data sets.Hyaluronidase(HAase)treatment was applied to remove the"HA coat",and RT-qPCR and Western blotting analysis were carried out to monitor changes in stemness-related molecules.CCK-8 assays,flow cytometry(FCM),and Hoechst 33258 staining were performed to determine changes in apoptosis and fulvestrant efficiency after HAase treatment.Results·IF results revealed that compared with MCF7 cells,the"HA coat"on the surface of MCF7/FulR cells was significantly thickened.IHC demonstrated markedly increased HA retention in fulvestrant-resistant mouse breast cancer tissues.ScRNA-seq and RNA-seq analyses indicated elevated expression of stemness-related genes and HA synthesis-associated genes in fulvestrant-resistant breast cancer cells.Correlation analysis revealed a positive association between HA synthesis and cancer stemness in ER+breast cancer.IF and RT-qPCR results demonstrated that removing the HA coating from the surface of MCF7/FulR cells led to a significant reduction in the expression of stemness-related molecules;concurrently,CCK-8 assays,FCM analysis,and Hoechst 33258 staining revealed that"HA coat"clearance reduced MCF7/FulR'tolerance to fulvestrant and increased apoptosis.Conclusion·Endocrine-resistant breast cancer cells develop an enriched"HA coat",which promotes stemness in fulvestrant-resistant tumors.Disruption of this HA coat through HAase treatment effectively reduces cell stemness,induces apoptosis,and re-sensitizes breast cancer cells to fulvestrant.

Objective:To explore the feasibility, safety, and short-term efficacy of a total pelvic floor resection procedure as a component of combined resection of pelvic organs for locally advanced or locally recurrent rectal cancer.Methods:This was a descriptive case series. Relevant clinical data of patients with locally advanced or locally recurrent rectal cancer without extrapelvic metastasis or with only oligometastasis who had undergone combined pelvic organ resection with resection of the entire pelvic floor in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Medical University from 1 January 2023 to 30 June 2024 were collected from a Chinese database of combined pelvic organ resection for rectal cancer. The study cohort comprised 143 patients, 74 of whom were male (51.7%) and 69 were female (48.3%); their ages averaged 54 (range: 31–75) years; 57 of the patients (39.9%) had locally advanced rectal cancer and 86 (60.1%) locally recurrent rectal cancer. In our institution, the pelvic floor is categorized into two anatomical layers: the levator ani/presacral anterior tissue, and the bone/ligament/pelvic floor soft tissue. The entire pelvic floor was resected en bloc after making incisions on both sides of the pelvic floor, followed by presacral sacral dissection, and abdominoperineal dissection of the anterior side of the pelvic floor. The main factors studied were related to the following: (1) surgical conditions, comprising the scope of surgical resection, operation time, intraoperative blood loss, tissue reconstruction; (2) postoperative recovery, comprising time to recovery of intestinal function, time to removal of drainage tubes, and time to healing of the empty pelvic cavity; and (3) postoperative complications, classified according to the international Clavien-Dindo classification. Results:Combined pelvic organ resection with entire pelvic floor resection was successfully completed in all patients. The operation time was 480 (390 to 1,020) minutes, intraoperative blood loss 800 (50 to 3,500) mL, and volume of blood transfused intraoperatively 1, 000 (400 to 7, 400). R0 resection was achieved in 116 cases (81.1%) and R1 resection in 27 (18.9%). The first layer of the pelvic floor wall (levator ani/sacral anterior tissue) was resected in 79 cases (55.2%) and the second layer of the pelvic floor wall (bone/ligament/pelvic floor soft tissue) in 64 (44.8%). The procedure was completed in the lithotomy position in 114 cases (79.7%) were and in the lithotomy + prone jackknife position in 29 (20.3%). The pelvic floor was reconstructed with mesh in 140 cases (97.7%) and with mesh plus pedicled omental flaps in 92 cases (64.3%). The urinary tract was reconstructed in 92 cases (64.3%). The time to recovery of intestinal function was 3.6 (2.0 to 7.0) days, to removal of drainage tubes 29.4 (24.0 to 54.0) days, and to healing of the empty pelvic cavity 36.2 (27.0 to 56.0) days. Twenty-three patients (16.1%) had Grade I - II complications and 36 (25.2%) Grade IIIa - IV complications. The median duration of follow-up was 15.5 (0.5 to 30.0) months. Six of the patients (4.2%) died, including two (1.4%) who died within 30 days after surgery.Conclusions:Pelvic floor en bloc resection has a high R0 resection rate and is a safe and feasible procedure for pelvic organ resection surgeries in patients with locally advanced or locally recurrent rectal cancer.

Objective:To explore the feasibility, safety, and short-term efficacy of a total pelvic floor resection procedure as a component of combined resection of pelvic organs for locally advanced or locally recurrent rectal cancer.Methods:This was a descriptive case series. Relevant clinical data of patients with locally advanced or locally recurrent rectal cancer without extrapelvic metastasis or with only oligometastasis who had undergone combined pelvic organ resection with resection of the entire pelvic floor in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Medical University from 1 January 2023 to 30 June 2024 were collected from a Chinese database of combined pelvic organ resection for rectal cancer. The study cohort comprised 143 patients, 74 of whom were male (51.7%) and 69 were female (48.3%); their ages averaged 54 (range: 31–75) years; 57 of the patients (39.9%) had locally advanced rectal cancer and 86 (60.1%) locally recurrent rectal cancer. In our institution, the pelvic floor is categorized into two anatomical layers: the levator ani/presacral anterior tissue, and the bone/ligament/pelvic floor soft tissue. The entire pelvic floor was resected en bloc after making incisions on both sides of the pelvic floor, followed by presacral sacral dissection, and abdominoperineal dissection of the anterior side of the pelvic floor. The main factors studied were related to the following: (1) surgical conditions, comprising the scope of surgical resection, operation time, intraoperative blood loss, tissue reconstruction; (2) postoperative recovery, comprising time to recovery of intestinal function, time to removal of drainage tubes, and time to healing of the empty pelvic cavity; and (3) postoperative complications, classified according to the international Clavien-Dindo classification. Results:Combined pelvic organ resection with entire pelvic floor resection was successfully completed in all patients. The operation time was 480 (390 to 1,020) minutes, intraoperative blood loss 800 (50 to 3,500) mL, and volume of blood transfused intraoperatively 1, 000 (400 to 7, 400). R0 resection was achieved in 116 cases (81.1%) and R1 resection in 27 (18.9%). The first layer of the pelvic floor wall (levator ani/sacral anterior tissue) was resected in 79 cases (55.2%) and the second layer of the pelvic floor wall (bone/ligament/pelvic floor soft tissue) in 64 (44.8%). The procedure was completed in the lithotomy position in 114 cases (79.7%) were and in the lithotomy + prone jackknife position in 29 (20.3%). The pelvic floor was reconstructed with mesh in 140 cases (97.7%) and with mesh plus pedicled omental flaps in 92 cases (64.3%). The urinary tract was reconstructed in 92 cases (64.3%). The time to recovery of intestinal function was 3.6 (2.0 to 7.0) days, to removal of drainage tubes 29.4 (24.0 to 54.0) days, and to healing of the empty pelvic cavity 36.2 (27.0 to 56.0) days. Twenty-three patients (16.1%) had Grade I - II complications and 36 (25.2%) Grade IIIa - IV complications. The median duration of follow-up was 15.5 (0.5 to 30.0) months. Six of the patients (4.2%) died, including two (1.4%) who died within 30 days after surgery.Conclusions:Pelvic floor en bloc resection has a high R0 resection rate and is a safe and feasible procedure for pelvic organ resection surgeries in patients with locally advanced or locally recurrent rectal cancer.

Objective To investigate the clinical characteristics,treatment strategies,and prognostic factors of adenoid cystic carcinoma(ACC)of the external auditory canal(EAC),and to provide evidence for optimizing surgical extent and adjuvant therapy.Methods A retrospective cohort study was conducted on 58 patients with pathologically confirmed ACC of the EAC treated in Department of Otorhinolaryngology Head and Neck Surgery,Beijing Tongren Hospital,Capital Medical University,between January 2001 and December 2021.All patients underwent surgical treatment,with some receiving adjuvant radiotherapy.The primary outcome was local recurrence,while secondary outcomes included overall survival(OS)and local recurrence-free survival(LRFS).Survival analysis was performed by the Kaplan-Meier method,and Cox regression models were used to identify risk factors for recurrence.Results The median follow-up time for the entire cohort was 6.27(3.25,11.30)years.The 1-year,3-year,and 5-year OS rates were 96.55％,91.37％,and 89.66％.43.10％of cases were classified as T4 stage at diagnosis,indicating advanced local progression.Local recurrence occurred in 23 patients(39.66％),and distant metastasis was observed in 28 patients(48.28％),with pulmonary metastasis accounting for 92.86％of cases.Multivariate analysis revealed that the solid histological pattern(HR=2.729,95％CI:1.025-7.226,P=0.044)and perineural invasion(PNI)(HR=9.891,95％CI:3.525-27.752,P＜0.01)were independent risk factors for local recurrence.Conclusion ACC of the EAC is characterized by a high propensity for local recurrence and distant metastasis.The solid histological pattern and perineural invasion are critical prognostic determinants.Multimodal therapy(surgery combined with adjuvant radiotherapy)may improve clinical outcomes,and early diagnosis and intervention are pivotal for enhancing survival rates.

Objective:To investigate the endocardial myocardial biopsy and ultrastructural features of heart failure patients with reduced ejection fraction, to determine their histopathologic phenotype, and to explore the diagnostic utility of endomyocardial biopsy in such patients.Methods:A total of 35 patients with heart failure with reduced ejection fraction diagnosed at Beijing Anzhen Hospital and underwent endomyocardial biopsy were collected between January 2022 and December 2023. The clinical features, histopathological, and ultrastructural characteristics were analyzed and compared with 11 patients with heart failure with preserved ejection fraction.Results:The age ranged from 35-58 years, with median age of 51 years; there were 26 males and 9 females. Myocardial fibrosis and myocardial fiber disorders were the most common histopathologic changes [97.1% (34/35) and 74.3% (26/35), respectively]. Myocardial fibrosis was not statistically different between the heart failure with reduced ejection fraction group and the heart failure with preserved ejection fraction group [13.3% (5.7%-21.4%) vs. 13.2% (9.3%-34.2%), P=0.279]. Significant ultrastructural changes were dense mitochondrial proliferation, vacuolar degeneration, and disorganized arrangement of myocardial fibers with localized lysis and fracture. After endomyocardial biopsy, the etiology was identified in 11 patients (31.4%,11/35), with a prevalence of cardiac amyloidosis of 17.1% (6/35). Conclusions:Endomyocardial biopsy is useful for early diagnosis and precise treatment in patients presenting with heart failure with reduced ejection fraction. Histopathological and ultrastructural analyses can uncover potential treatments, and predict and improve prognosis by providing relevant information for understanding the pathogenesis and clinical evolution.

Objective:To investigate the clinical and pathological characteristics, prognostic factors, and treatment outcomes of bladder adenocarcinoma.Methods:The data of 177 bladder adenocarcinoma patients treated at Renji Hospital, Shanghai Jiaotong University School of Medicine from January 2003 to December 2023, and 2 687 bladder adenocarcinoma patients from the SEER database (2000—2021) were reviewed retrospectively. The clinicopathological and prognostic characteristics were compared between the two cohorts. Patients with urachal adenocarcinoma or primary bladder adenocarcinoma were included, while metastatic bladder adenocarcinoma from other sites and urothelial carcinoma with glandular components were excluded. The Chi-square test was used for comparison of categorical data, and propensity score matching (1∶1) was applied to match baseline data between the Renji and SEER cohorts. Kaplan-Meier survival curves were generated, and log-rank tests were used for comparisons. Univariate and multivariate Cox regression analyses were performed using the survival R package, with P-values calculated via Wald tests. Results:The proportion of localized bladder adenocarcinoma was significantly higher in the Renji cohort than in the SEER cohort [61.0% (108/177) vs. 19.4% (521/2 687), P<0.001], and mucinous adenocarcinoma was more common in Renji cohort [33.3% (59/177) vs. 22.6% (607/2 687), P<0.001]. After matching for baseline factors, including SEER stage and pathological grade, survival analysis revealed that the Renji cohort patients had slightly better survival compared to the SEER cohort [median survival: 55.4 (24.1, 196.2) months vs. 39.2 (13.6, 137.4)months, P=0.033]. Multivariate Cox analysis identified SEER stage [Renji cohort: HR=3.83 (95% CI 1.62-9.07), P=0.002; SEER cohort: HR=3.67 (95% CI 3.13-4.31), P<0.001] and pathological grade [Renji cohort: HR = 2.76 (95% CI 1.54-4.95), P=0.001; SEER cohort: HR=1.46 (95% CI 1.29-1.65), P<0.001] as independent prognostic factors. In the Renji cohort, no significant differences were observed in the median progression-free survival [40.1 (19.5, 91.6) months vs. 40.9 (12.8, not reached)months, P=0.976] and overall survival [79.3 (37.1, 195.8) months vs. 53.9 (16.4, 129.5)months, P=0.374] between patients receiving adjuvant chemotherapy and those not receiving it. However, among patients with lymph node-positive bladder adenocarcinoma, adjuvant chemotherapy significantly improved both progression-free survival [40.1 (38.2, 75.4) months vs. 12.2 (3.1, 12.2)months, P=0.004] and overall survival [68.2 (46.2, 84.5)months vs. 28.1 (4.3, 28.3)months, P=0.006]. Conclusions:Bladder adenocarcinoma is rare and associated with poor prognosis. Compared to the SEER cohort, Renji cohort patients had more localized disease, with no significant differences in other features. SEER stage and pathological grade were independent prognostic factors in both cohorts. Lymph node-positive bladder adenocarcinoma patients in the Renji cohort benefited significantly from adjuvant chemotherapy.

Objective:To determine the best scoring system for assessing the severity of perioperative aortic dissection.Methods:All data were obtained from the Medical Information Mart for Intensive Care-Ⅳ(MIMIC-Ⅳ) database in the United States. The predictive value of the Acute Physiology Score Ⅲ(APS Ⅲ), Oxford Acute Severity of Illness Score (OASIS), Sequential Organ Failure Assessment (SOFA), Simplified Acute Physiology Score Ⅱ(SAPS Ⅱ), and Charlson Comorbidity Index (CCI) scoring systems were evaluated using the receiver operating characteristic ( ROC) curve. The area under the curve ( AUC) was used to determine the best predictive score, and the ideal cutoff value of the score was calculated based on the Youden index. Patients were divided into high and low groups according to the cutoff value. The Kaplan- Meier curve was used to show the impact on the survival rate of patients with aortic dissection. Results:ROC curve analysis showed that APS Ⅲ( AUC: 0.803, 95% CI: 0.721-0.885) was superior to SAPS Ⅱ( AUC: 0.767, 95% CI: 0.654-0.880), OASIS( AUC: 0.760, 95% CI: 0.635-0.885), SOFA( AUC: 0.753, 95% CI: 0.649-0.857), and CCI( AUC: 0.670, 95% CI: 0.524-0.817) in assessing in-hospital mortality. Based on the ROC curve and the Youden index calculation, the ideal cutoff value of the APS Ⅲ score was 57.5. Kaplan- Meier survival analysis showed that patients in the high group of APS Ⅲ had a shorter 28-day survival time. Patients in the high group of APS Ⅲ had a higher incidence of postoperative complications, and correlation analysis showed that patients in the high group of APS Ⅲ had a longer hospital stay. Conclusion:The APS Ⅲ scoring system is more valuable in predicting the 28-day mortality and prognosis of patients with aortic dissection.