ObjectiveTo evaluate the therapeutic effect of Huazhuo SanJie Chubi presciption （HSCD） on chronic gouty arthritis （CGA） rats with low-grade inflammation and to explore the underlying mechanism with a focus on macrophage polarization. MethodsThe 41 male 6-week-old SD rats were randomly allocated， using the random number table， to a normal group （n=8） and a model group （n =33）. CGA with low-grade inflammation was induced in the model group by daily gavage of potassium oxonate （250 mg·kg^-1·d^-1） and hypoxanthine （300 mg·kg^-1·d^-1）， combined with intra-articular injection of a monosodium urate （MSU） crystal suspension （50 μL， 25 g·L^-¹） into the left ankle twice weekly. After 4 weeks of modeling， 3 rats were randomly selected from each group for model validation. The remaining successfully modeled rats were randomly divided into a model group， an HSCD group （10.35 g·kg^-1·d^-1， gavage once daily）， an M1 polarization agonist group （L-methionine sulfoximine， 300 mg·kg^-1， subcutaneous injection every other day）， an M1 polarization agonist + HSCD group， an M2 polarization inhibitor group （PD0325901， 10 mg·kg^-1·d^-1， gavage once daily）， and M2 polarization inhibitor + HSCD group. The corresponding drug or drug combination was administered according to group assignment， whereas rats in the normal and model groups received 0.5% carboxymethyl cellulose sodium （CMC-Na） vehicle （10.35 g·kg^-1·d^-1， gavage once daily）. All interventions were continued for four weeks. During the intervention period， except for the normal group， potassium oxonate （250 mg·kg⁻¹） and hypoxanthine （300 mg·kg^-1） were co-administered by gavage every other day to maintain the model. At the end of treatment， serum uric acid （SUA）， ankle joint diameter and joint swelling index were measured. The levels of high-sensitivity C-reactive protein （hs-CRP）， interleukin-1β （IL-1β）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， chemokine C-C motif ligand 2 （CCL2）， S100 calcium-binding protein A8/A9 （S100A8/A9）， interleukin-10 （IL-10） and arginase-1 （Arg-1） in serum and joint fluid were determined by enzyme-linked immunosorbent assay （ELISA）. High-frequency ultrasound was used to assess MSU deposition in the ankle joint. Hematoxylin-eosin （HE） staining was performed to evaluate synovial histopathological changes. Quantitative Real-time PCR and immunofluorescence were used to detect the mRNA and protein expression of the M1 macrophage polarization markers inducible nitric oxide synthase （iNOS） and the M2 macrophage polarization marker scavenger receptor cysteine-rich type 1 protein M130 （CD163） in synovial tissue. ResultsCompared with the normal group， the model group showed significantly elevated SUA level and joint swelling index， and increased levels of pro-inflammatory cytokines， CCL2， and S100A8/A9 in both serum and joint fluid （P<0.05）， accompanied by MSU deposition and synovial inflammation in the ankle joint. The mRNA and protein expression levels of macrophage polarization M1/M2 markers iNOS and CD163 in synovial tissues were also significantly up-regulated （P<0.05）. Compared with model group， rats in HSCD group had significantly lower SUA levels， attenuated joint swelling， reduced serum levels of pro-inflammatory cytokines， and decreased levels of CCL2 and S100A8/A9 in both serum and joint fluid， accompanied with alleviated MSU deposition and synovial inflammation （P<0.05）. HSCD markedly downregulated the mRNA and protein expression of M1 marker iNOS （P<0.05）， whereas it had no significant effect on the expression of M2 marker CD163. Compared with the M1 polarization agonist group， the M1 polarization agonist + HSCD group showed significantly reduced joint swelling， lower serum levels of pro-inflammatory cytokines， and decreased levels of CCL2 and S100A8/A9 in joint fluid （P<0.05）. In addition， synovial inflammatory cell infiltration and angiogenesis were attenuated， and iNOS mRNA and protein expression levels were significantly reduced （P<0.05）. Compared with the M2 polarization inhibitor group， the M2 polarization inhibitor + HSCD group exhibited reduced joint swelling， decreased levels of CCL2 and S100A8/A9 in joint fluid and ameliorated synovial inflammation （P<0.05）， whereas the levels of anti-inflammatory mediators （IL-10， Arg-1） and CD163 mRNA and protein expression were not significantly increased. ConclusionHSCD alleviates low-grade inflammation in CGA rats， at least in part， by inhibiting macrophage polarization toward the M1 phenotype.

ObjectiveThis paper aims to observe the effect of Huazhuo Sanjie Chubi prescription （HSCD） on the gouty bone erosion model rats and investigate its action mechanism. MethodsThirty-six two-month-old male SD rats were randomly divided into the blank group with nine rats and the modeling group with 27 rats. The rats in the modeling group were administered hypoxanthine solution at 300 mg·kg^-1·d^-1 and potassium oxonate solution at 250 mg·kg^-1·d^-1， combined with intra-articular injection of 200 μL monosodium urate （MSU） crystal suspension at 25 g·L^-1 into the right ankle joint （joint injection once every three days）， so as to induce the gouty bone erosion model. After four weeks of modeling， three rats were selected from these two groups to validate the model. The modeled 24 rats were randomly divided into the model group， HSCD group （10.35 g·kg^-1·d^-1）， allopurinol group （20 mg·kg^-1·d^-1）， and inhibitor group （LY294002， 10 mg·kg^-1·d^-1）， with six rats per group. Except for the blank group， rats in all other groups continued to receive hypoxanthine solution at 300 mg·kg^-1 and potassium oxonate solution at 250 mg·kg^-1 via gavage concurrently with administration to maintain modeling intervention. The rats in the HSCD group and allopurinol group received administration by gavage at the above doses. The rats in the inhibitor group received an intraperitoneal injection at the above dose. The rats in the blank group and model group received saline （10.35 g·kg^-1·d^-1） by gavage for four consecutive weeks. After administration， ankle joint swelling of the rats in all groups was observed， and the diameters were measured. Bone volume fraction （BV/TV） and bone surface area to bone volume （BS/BV） were observed and quantitatively analyzed by Micro-CT. Histopathological changes in the ankle joint were observed by hematoxylin-eosin （HE） staining and safranin O-fast green staining. The uric acid in the rats' serum was determined by enzyme colorimetry. The levels of inflammatory factors， including tumor necrosis factor-α （TNF-α）， interleukin （IL）-1β， and IL-6 were measured by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of receptor activator of nuclear factor-κB ligand （RANKL） and phosphorylated （p）-phosphatidylinositol-3-kinase （PI3K） in ankle joint tissues of rats were detected by immunofluorescence staining. The mRNA levels of the proteins related to the bone erosion， including RANKL， tartrate-resistant acid phosphatase （TRAP）， cathepsin K （CTSK）， and matrix metalloproteinase-9 （MMP-9） in the ankle joint tissues of rats were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expressions of the proteins related to the bone erosion， including RANKL， CTSK， TRAP， MMP-9， and the proteins related to the PI3K/protein kinase B （Akt） signaling pathway， including PI3K， Akt， mammalian target of rapamycin （mTOR）， p-PI3K， phosphorylated protein kinase B （p-Akt）， and phosphorylated mammalian target of rapamycin （p-mTOR）， were detected by Western blot. ResultsCompared with the blank group， the modeling group showed marked ankle swelling and increased diameter. Micro-CT revealed an uneven articular surface and honeycomb-like bone erosion in the ankle joint. Quantitative analysis showed decreased BV/TV and increased BS/BV （P<0.05）. HE staining revealed a narrowed joint space， rough and discontinuous cartilage surfaces， reduced and unevenly distributed chondrocytes， partial hypertrophy， and blurred tidemarks， confirming successful model establishment. After four weeks of intervention， compared with those in the blank group， the rats in the model group exhibited severe ankle swelling and increased diameters （P<0.05）. Micro‑CT showed that the ankle joint surface was irregular， and bone erosion exhibited a honeycomb‑like morphology. The microstructural parameters of the bone revealed a decreased BV/TV and an increased BS/BV （P<0.05）. Histopathological examination revealed a narrowed joint space and severe articular cartilage destruction. The levels of uric acid in the serum and inflammatory factors （IL-1β， IL-6， and TNF-α） were increased （P<0.05）. The mRNA and protein levels of the proteins related to bone erosion in joint tissue， including RANKL， CTSK， TRAP， and MMP-9， were upregulated （P<0.05）. The ratios of p-PI3K/PI3K， p-Akt/Akt， and p-mTOR/mTOR in the proteins related to the PI3K/Akt signaling pathway were increased （P<0.05）. RANKL and p-PI3K protein fluorescence intensities were elevated （P<0.05）. Compared with those in the model group， the above indicators in all other administration groups showed varying degrees of improvement. The HSCD group and inhibitor groups exhibited more significant effects in reducing ankle swelling， improving bone erosion， bone microstructure （significant decrease in BV/TV and increase in BS/BV）， and the pathology of cartilage erosion， lowering inflammatory factor levels， downregulating the proteins related to the bone erosion， and suppressing activation of the PI3K/Akt/mTOR pathway （P<0.05）. The uric acid levels in rats' serum were reduced in both HSCD and allopurinol groups （P<0.05）. Compared with those in the HSCD group， the rats in the allopurinol group had larger ankle diameters （P<0.05）， more severe bone erosion and bone microstructure damage （P<0.05）， worse improvement of the pathology of cartilage erosion， higher levels of IL-6 and TNF-α （P<0.05）， elevated expressions of the proteins related to the bone erosion， higher expression ratio of proteins related to the PI3K/Akt signaling pathway （P<0.05）， and higher fluorescence intensities of RANKL and p-PI3K proteins （P<0.05）. The inhibitor group achieved comparable results to the HSCD group in improvements of bone microstructure and the reduction of IL-1β and IL-6， stronger suppression of TNF-α and PI3K/Akt/mTOR signaling pathway activation （P<0.05）， but weaker effects on cartilage repair and serum uric acid reduction （P<0.05）. ConclusionHSCD effectively reduces uric acid levels in serum， suppresses inflammatory factor secretion， and downregulates the expressions of proteins related to bone erosion， including RANKL， CTSK， TRAP， and MMP-9 in the joint tissues. Its action mechanism of improving gouty bone erosion may be associated with inhibition of the PI3K/Akt signaling pathway.

ObjectiveBiochemistry and Molecular Biology, a discipline that elucidates life phenomena at the molecular level, serves as a core foundational course in medical education. It provides the theoretical basis for studying other basic and clinical medical subjects, as well as for understanding pathogenesis, disease diagnosis, and treatment. However, its complex content and highly abstract concepts have posed a dual challenge to traditional teaching models: “inefficient instruction” and “inadequate learning outcomes”. Within limited classroom hours, how to engage students and stimulate their intrinsic motivation, and how to help them recognize, understand, and develop a passion for biochemistry from the perspective of the discipline’s essence, have long been key focuses of curriculum research. MethodsUsing the lipid metabolism chapter as an example, this study employs “Rain Classroom”, a generative artificial intelligence (AI)-assisted platform, to support education in four dimensions: teaching, learning, evaluation, and research. In teaching, it assists instructors through virtual experiments, lesson preparation support, knowledge mapping, and assignment design. For learning, it serves as an intelligent study assistant for students, providing automated assignment review, enabling educational resource sharing, and facilitating personalized learning pathways. In evaluation, the platform automates assignment grading, analyzes student performance data, and offers diagnostic feedback and teaching recommendations. In research, it aids educators in collecting and analyzing teaching data, as well as searching for and summarizing relevant literature. ResultsThe results indicate that an educational model integrating teacher-led instruction, student-centered learning, and generative AI assistance significantly enhances teaching quality, students’ self-directed learning abilities, and knowledge mastery. Furthermore, with the support of generative AI, curriculum-based ideological education—focusing on cutting-edge disciplinary advances and topical medical issues—helps cultivate students’ medical spirit of “honoring life and healing the wounded”, thereby fostering the establishment of appropriate professional values. Finally, while generative AI presents both opportunities and challenges for higher education, this study also analyzes potential risks in its teaching applications, emphasizing the need for both instructors and students to avoid over-reliance and to ensure that technological tools consistently serve the fundamental goals of education. ConclusionThis study demonstrates that integrating generative AI, specifically via the “Rain Classroom” platform, can effectively enhance biochemistry education. By supporting teaching, learning, evaluation, and research, this approach improves both educational effectiveness and student outcomes. It also facilitates the incorporation of cutting-edge knowledge and professional ethics, nurturing a patient-centered mindset. Additionally, the study addresses potential implementation risks to ensure that such technological tools remain aligned with the core purpose of education.

ObjectiveTo observe the protective effect of Erchentang （ECT） on SiO₂-induced lung injury in rats and to explore its underlying mechanism. MethodsA rat model of lung injury was established by a single intratracheal instillation of 50 mg·mL^-1 SiO₂ suspension. Thirty male Sprague-Dawley （SD） rats were randomly assigned to five groups： control， model， low and high-dose （4.5 g·kg^-1·d^-1 and 9 g·kg^-1·d^-1， respectively） ECT， and dexamethasone （0.2 mg·kg^-1·d^-1）. All the groups were treated for 4 consecutive weeks. Histopathological alterations in the lung tissue were examined by hematoxylin and eosin （HE） staining. The levels of malondialdehyde （MDA）， superoxide dismutase （SOD）， and glutathione peroxidase （GSH-Px） in the lung tissue were measured through biochemical assays. The expression of key molecules in the nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） pathway was determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， Western blot， and immunofluorescence assay. The primary active components of ECT were identified by ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）， and their binding affinity to Nrf2/HO-1 was assessed by molecular docking. Untargeted metabolomics of the lung tissue was performed based on UPLC-quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS）， and correlation analysis was performed to identify differential metabolites and parameters closely associated with the Nrf2/HO-1 pathway. ResultsCompared with the control group， the model group exhibited a reduction in body weight gain， an increase in lung index， increased MDA content， weakened SOD and GSH-Px activities in the lung tissue， down-regulated mRNA and protein levels of Nrf2 and protein levels of HO-1 and GPX4， and an up-regulated protein level of Keap1 （P<0.05， P<0.01）. Treatment with ECT attenuated the SiO₂-induced decline in body weight （P<0.05）， alleviated inflammatory cell infiltration and silicotic nodule formation in alveoli， and reduced the MDA content and enhanced the SOD and GSH-Px activities in the lung tissue （P<0.05， P<0.01）. UPLC-MS/MS and molecular docking revealed that core components of ECT， such as hesperidin and glycyrrhizic acid， displayed strong binding affinity to Nrf2/HO-1. Molecular biological experiments demonstrated that ECT promoted nuclear translocation of Nrf2， up-regulated the mRNA and protein levels of HO-1 and GPX4， and down-regulated Keap1 expression （P<0.05， P<0.01）. Metabolomic analysis indicated that ECT reversed the SiO₂-induced aberrant expression of metabolites， including linoleic acid and glutamine （P<0.05， P<0.01）. Correlation analysis showed that Nrf2 and HO-1 were positively correlated with SOD and GSH-Px （P<0.05， P<0.01）， but negatively correlated with glutamine and serine （P<0.05， P<0.01）. ConclusionECT may activate the Nrf2/HO-1 pathway through its core active components， thereby regulating oxidative stress and metabolic disorders to ameliorate SiO₂-induced lung injury in rats. This study provides experimental evidence for ECT in the prevention and treatment of occupational lung injury.

Background: and Purpose Vertebrobasilar fusiform aneurysms (VBFAs) carry substantial morbidity and mortality, but optimal management for unruptured VBFAs remains unclear. We compared the safety and efficacy of conservative management (CM), stent-assisted coiling (SAC), and flow diverters (FDs) in patients with unruptured VBFAs, focusing on long-term prognosis. Methods: This study included data from a nationwide Chinese cohort of patients with vertebrobasilar dissecting aneurysms. Inverse probability of treatment weighting (IPTW) balanced confounders across groups. The primary outcome was poor prognosis (modified Rankin Scale score >2). Secondary outcomes included aneurysm rupture, ischemic stroke, compression symptoms, and VBFA-related deaths. Logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup and sensitivity analyses were performed. Results: Among 1,115 patients with unruptured VBFAs, 838 (median age, 54 years; 655 men) were included. After IPTW, baseline characteristics were balanced. Median follow-up was 54 months. FD was associated with a lower risk of poor prognosis than CM (OR, 0.48 [95% CI, 0.30 to 0.77]; p=0.002), with no difference between CM and SAC. FD also reduced aneurysm rupture (OR, 0.20 [95% CI, 0.07 to 0.60]; p=0.004) and compression symptoms (OR, 0.30 [95% CI, 0.13 to 0.68]; p=0.004) versus CM. Time-to-event analyses further revealed significant differences in vertebral artery lesions and Type I–II VBFAs, whereas no significant differences were observed in basilar or vertebrobasilar junction lesions or in Type III–IV VBFAs. Conclusions Compared with CM, FD was associated with improved long-term outcomes in unruptured VBFAs, particularly in vertebral artery lesions and Type I–II VBFAs, although residual confounding cannot be excluded.

Background/Aims: Liver transplantation (LT) following total hepatectomy is a life-saving treatment for hepatocellular carcinoma (HCC). The HCC recurrence after LT hinders the effectiveness of the procedure. The objective of this study is to develop a pre-operative risk stratification model based on a liquid biopsy. Methods: We conducted a comprehensive multi-omics study of 260 HCC patients from three centers, including clinical data, low-coverage whole-genome sequencing of cell-free DNA (cfDNA) from plasma, as well as whole-exome, single-nucleus RNA, and spatial transcriptomics from matched tumor and non-tumor tissues. Results: We identified cfDNA-derived copy number alteration (CNA) signatures associated with post-transplant recurrence. By integrating cfDNA-derived CNA profiles with single-cell transcriptomic data, we traced recurrence-associated cfDNA to a distinct subpopulation of malignant cells within the primary tumor. These cells were embedded in a pro-metastatic microenvironment of specialized endothelial subtypes and cancer-associated fibroblasts. Notably, most recurrence-associated lesions were detectable in cfDNA prior to liver transplantation (LT). Building on these insights, we developed the ZJU Criteria based on CNA fragments and tumor markers, a pre-LT risk prediction tool that integrates conventional clinical factors with cfDNA-derived CNA signatures, and validated it using internal and independent external cohorts. Conclusion Our findings suggest that post-transplant recurrence commonly originates from advanced subclones that emerge late during tumor evolution. The ZJU Criteria provides an accurate, non-invasive strategy that significantly improves pre-LT risk stratification and clinical decision-making for patients with HCC.

ObjectiveHepatocellular carcinoma (HCC) represents 90% of all primary liver cancers. The main risk factors associated with HCC include viral hepatitis (B and/or C), alcohol abuse, and metabolic dysfunction-associated steatotic liver disease (MASLD), which progressively advance to liver fibrosis, cirrhosis, and ultimately evolve into HCC. Surgical resection represents the most effective treatment for HCC, while recent advances in immunotherapy, including immune checkpoint inhibitors and adoptive cell therapies, have provided improved treatment prospects for patients with unresectable HCC. However, the complex metabolic heterogeneity of HCC limits the therapeutic efficacy. Metabolic intermediates acyl-CoA not only provide energy and substrates for numerous biochemical reactions but also serve as donors for protein lysine acylation, a major class of post-translational modification (PTM). Therefore, a deeper understanding of the molecular mechanisms underlying protein lysine acylation and hepatocarcinogenesis is urgently needed. MethodsThe levels of protein lysine acylation and silence information regulator 5 (SIRT5) expression levels in clinical HCC samples were analyzed by Western blot. Quantitative malonylome and succinylome of HCC samples were analyzed by antibody-based affinity enrichment coupled with tandem mass spectrometry. The proliferation of HCC cells was analyzed with Cell Counting Kit-8 (CCK-8) assays, the apoptosis was quantified by Annexin V-FITC/propidium iodide (PI) staining coupled with flow cytometry, and the ability of cells to migrate was assayed by Transwell assays. The enzymatic activity of glutathione S-transferase Mu 1 (GSTM1) was quantified. Transgenic mice with hepatic overexpression of SIRT5 were constructed using CRISPR-Cas9, and primary hepatocarcinogenesis was induced by administration of diethylnitrosamine. ResultsWestern blot analysis indicated that the expression level of SIRT5 was elevated in clinical samples from HCC patients, and the levels of lysine malonylation, glutarylation, and succinylation were significantly reduced in HCC tissues. Knockout of SIRT5 in MHCC-97H and MHCC-97L hepatoma cells suppressed cell proliferation, and increased the percentage of apoptotic cells significantly. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the differentially malonylome and succinylome of HCC samples revealed significant enrichment in two major classes of biological processes: core energy metabolism (e.g., glycolysis/gluconeogenesis, tricarboxylic acid metabolic process, fatty acid beta oxidation) and detoxification and oxidative stress response (e.g., response to toxic substance, chemical carcinogenesis, reactive oxygen species (ROS)). SIRT5 removes malonylation from lysine residues in GSTM1 and restores its detoxification activity, which is crucial for the survival of hepatocytes under stressed conditions. More importantly, in vivo experiment indicated that hepatic-specific overexpression of SIRT5 in mice accelerated diethylnitrosamine-induced liver fibrosis and hepatocarcinogenesis, indicating the critical role of SIRT5 in HCC progression. ConclusionThis study highlights the previously unrecognized SIRT5-GSTM1 axis as a key regulator in hepatocarcinogenesis, and suggests a potential target for the treatment of patients with HCC.

Background As one of the key populations in the prevention and treatment of iodine deficiency disorders, it is important to continuously monitor the iodine nutritional level of school-age children. The current reference interval for thyroid volume in China is based on age only, without taking into account differences in individual developmental levels, and the distribution of thyroid volume may vary regionally due to economic, demographic, and environmental factors. The current reference cut-off points for thyroid volume proposed by the World Health Organization are not based on the Chinese population. Objective To understand the iodine nutritional status and distribution of thyroid volume (Tvol) among children aged 8-10 years in Huangpu District, Shanghai, China, to identify impact factors of Tvol, and to propose a reference range upper limit for local thyroid health surveillance, so as to provide a basis for goiter control and prevention. Methods Six hundred children aged 8-10 years in Huangpu District were recruited in 2017, 2020, and 2023, and body height, weight, thyroid volume, urinary iodine, and iodine content of household edible salt were determined. A multilevel model was constructed using population density and area as regional variables, and age, body surface area (BSA), and body mass index (BMI) as potential impact factors for at the individual level, to assess their effects on thyroid volume. Quantile regression of thyroid volume was performed, and the 98th percentile (P₉₈) of thyroid volume was predicted based on age and BSA. Results The iodized salt coverage in the households of surveyed children in 2017, 2020, and 2023 was 72.0%, 57.0%, and 48.0%, respectively, and the iodized salt coverage decreased by year (χ²=24.31, P<0.001). The urinary iodine level of children in 2017 was higher than that in 2020 and 2023 (χ²=18.77, P<0.001). The Tvol medians of children in 2017, 2020, and 2023 were 2.29, 2.49, and 2.97 mL, respectively, and the Tvol increased by year (χ²=60.04, P<0.001). The proportion of goiter was higher in children in 2023 than in 2017 and 2020 (χ²=6.57, P<0.05). Sex differences were not statistically significant for urinary iodine levels, thyroid volume, and goiter. The median Tvol was 2.26, 2.58, and 2.76 mL in children of 8, 9, and 10 years old respectively, and the Tvol increased with age (χ²=49.02, P <0.001). Tvol was positively correlated with age, BSA, and BMI with correlation coefficients of 0.2846, 0.3723, and 0.2950, respectively. The final quantile regression model showed that the strongest effect of BSA was associated with the 98th percentile of Tvol. Multilevel models considering population density or area as regional variables failed to achieve convergence. Conclusion To establish the upper limit of the reference interval for thyroid volume of healthy children in Huangpu District, the effects of age and BSA should be considered at the individual level, and the upper limit of the normal interval for goiter screening is suggested to be the 98th percentile value of BSA at the same age. In addition, the adaptability of population density and regional area as indicators of regional aggregation of thyroid volume distribution still needs to be further explored.

Deep infiltrating endometriosis(DIE)is defined as endometriotic lesions infiltrating≥5 mm beneath the peritoneum,commonly affecting the uterosacral ligaments,rectovaginal septum,vaginal vault,and rectal wall.Due to nonspecific clinical manifestations and atypical imaging features,DIE is often misdiagnosed.This study reports a case of rectal DIE diagnosed preoperatively by endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)and summarizes the multidisciplinary treatment experience in conjunction with a literature review.A 35-year-old woman was admitted for defecation difficulty.MRI and EUS-FNA confirmed rectal DIE.After multidisciplinary team(MDT)evaluation involving colorectal,gynecologic,and urologic specialists,laparoscopic resection of the rectal lesion,sigmoid-rectal anastomosis,and protective ileostomy were performed.Pathology confirmed rectal DIE with negative margins.The stoma was successfully reversed 4 months later,and no recurrence was observed during 21 months of follow-up.These findings highlight the pivotal role of EUS-FNA in early diagnosis and demonstrate that an MDT approach led by colorectal surgeons can significantly enhance surgical safety and completeness,providing valuable guidance for the individualized management of complex pelvic endometriosis.