[摘 要] 目的：探讨DNA甲基转移酶1（DNMT1）通过稳定zeste基因增强子同源物2（EZH2）促进结直肠癌（CRC）HCT8细胞增殖与迁移的机制。方法：利用生物信息学方法分析DNMT1在CRC组织中的表达水平。WB法检测DNMT1在CRC细胞HCT8、SW620和正常结肠上皮细胞NCM460中的表达。通过siRNA或慢病毒载体转染HCT8细胞，分为siNC组、siDNMT1组、Vector组、DNMT1-OE组、siTRAF6组、siEZH2组、siEZH2 + DNMT1-OE组。采用克隆形成实验、CCK-8法、Transwell实验和划痕愈合实验检测敲低或过表达DNMT1对HCT8细胞增殖与迁移的影响，WB和qPCR法检测EZH2蛋白和mRNA水平，免疫沉淀（IP）法检测EZH2泛素化水平，免疫荧光双染检测肿瘤坏死因子受体相关因子6（TRAF6）与EZH2的细胞内共定位情况，克隆形成和划痕愈合实验验证EZH2对DNMT1功能的逆转作用。收集2022—2025年间郑州大学附属洛阳中心医院手术切除的12例CRC患者的癌及癌旁组织标本，采用免疫组化法检测CRC组织中DNMT1、TRAF6和EZH2的表达水平。结果：DNMT1在CRC组织中表达显著高于癌旁组织（P < 0.01），且在CRC细胞中表达上调（P < 0.05）；DNMT1敲低显著抑制HCT8细胞增殖及迁移（均P < 0.01），过表达则相反（均P < 0.01）。DNMT1正向调控EZH2的蛋白水平（P < 0.01），而mRNA水平不变（P > 0.05）。MG132可恢复siDNMT1组的EZH2蛋白表达（P < 0.01），且siDNMT1组EZH2泛素化水平升高。DNMT1负向调控TRAF6的表达（P < 0.01），且TRAF6与EZH2在细胞质中共定位，IP证实两者直接结合。敲低TRAF6可减弱EZH2的泛素化水平，敲低EZH2可逆转DNMT1对HCT8细胞增殖、迁移的促进作用（均P < 0.01）。DNMT1和EZH2在CRC组织中呈高表达（P < 0.01），TRAF6在CRC组织中表达显著低于癌旁组织（P < 0.05）。结论：DNMT1通过抑制TRAF6稳定EZH2促进CRC细胞的增殖和迁移，DNMT1、TRAF6和EZH2可能是CRC治疗的潜在靶点。

ObjectiveTo investigate the lower limb muscle synergy patterns during jumping in patients after anterior cruciate ligament reconstruction (ACLR). MethodsFrom March to November, 2022, 23 patients after ACLR were enrolled as observation group, and 24 healthy ones matched in height, body mass and exercise level were recruited as control group at Wuhan Sports University. Surface electromyography (sEMG) data of lower limb muscles were collected during a single-leg vertical jump task. Non-negative matrix factorization was applied for synergy analysis. The number of synergies, variance accounted for, synergy structure (muscle weight) and activation coefficient were extracted. ResultsThree types of muscle synergy patterns were identified on the affected side and contralateral side of the observation group, and the control group. For Synergy 1, the weight of biceps femoris was higher on both the affected and contralateral sides than in the control group (P < 0.01); the weight of semitendinosus was higher on the affected side than on the contralateral side (P < 0.05). For Synergy 2, the weight of lateral gastrocnemius and soleus were higher on both sides of the observation group than in the control group (P < 0.05). For Synergy 3, the weight of gluteus maximus was lower on the affected side than on the contralateral side and in the control group (P < 0.05); the weight of tibialis anterior was higher on the affected side than on the contralateral side and in the control group (P < 0.001); the weight of vastus lateralis was lower on the contralateral side than on the affected side and in the control group (P < 0.001). In the observation group, the peak activation time and stop time of Synergy 3 were delayed bilaterally (P < 0.05). ConclusionPatients after ACLR exhibit altered structural and temporal characteristics of lower limb muscle synergy during jump task. The hamstrings show increased participation during the pre-activation phase, and calf muscles undertake more stabilizing functions during the landing phase.

OBJECTIVE To investigate the cognition， attitudes， and current practices of Chinese physicians regarding biosimilars and their clinical switching， so as to provide a basis for the rational clinical application of biosimilars in China and the improvement of related policies.METHODS A national cross-sectional online questionnaire survey was conducted in 2025. Quota sampling was adopted， with quotas based on physicians’ sex， city tier， and specialty. Questionnaire invitations were distributed to licensed physicians， and physicians who had prescribed monoclonal antibody biosimilars were included for analysis. The questionnaire covered their familiarity with biosimilars， attitudes， clinical switching practices， and reasons. Data were processed using reliability and validity tests， dispersion analysis， and cross-tabulation analysis.RESULTS The questionnaire scale showed good reliability and validity， with Cronbach’s α coefficient ＞0.7 and KMO value ＞0.6. A total of 2 071 survey invitations were distributed， and 300 valid questionnaires were returned， with an effective response rate of 14.5%. Among the respondents， 75.3% had prescribed 3-5 types of monoclonal antibody biosimilars； only 35.3% were aware that China currently has no clear regulatory provisions on biosimilar switching； 46.3% and 47.3% of respondents believed that there was no difference in safety and efficacy， respectively， between biosimilars and originator products； 63.0% of respondents were concerned about the immunogenicity risk of long-term switching between originator drugs and biosimilars. A total of 92.3% of respondents had experience with biosimilar switching， 87.7% of which involved switching from originator products to biosimilars， and 28.2% of respondents had completed three or more switches in the same patient. Among the primary reasons for switching， non-medical factors accounted for 57.4%， higher than medical factors at 42.6%； “lower treatment cost after switching” was the most important reason for switching； 95.3% of respondents believed that informed consent should be obtained from patients before switching.CONCLUSIONS The surveyed physicians had basic knowledge of biosimilars， but their understanding of the relevant regulations of the national drug regulatory authority was insufficient. Although most physicians were concerned about the risks of non-medical switching， clinical switching was mostly driven by non-medical factors. It is recommended to strengthen policy education for medical professionals and standardize clinical switching behavior. The National Medical Products Administration should also promptly improve the interchangeability review standards and post-marketing surveillance system for biosimilars, so as to promote the rational use of biosimilars.

OBJECTIVE Aimed at investigating whether reflux pharyngitis is an independent risk factor for the failure of type Ⅰ tympanoplasty for chronic otitis media.This is achieved by analyzing the relationship between the postoperative tympanic membrane healing in patients who underwent type Ⅰ tympanoplasty and pharyngolaryngeal reflux finding score(RFS).METHODS Patients who underwent type Ⅰ tympanoplasty in the Department of Otolaryngology Head and Neck Surgery,Nanshan People's Hospital,Shenzhen,China,from January 2023 to July 2024 were retrospectively included.All the patients received preoperative perfect nasal endoscopy,laryngoscopy,evaluation by the RFS questionnaire,preoperative otoscopy for tympanoplasty,pure tone hearing threshold,and temporal bone thin-layer CT examination.Postoperative otoscopic examination was performed to observe tympanic membrane healing and followed up for 3 months.The patients were divided into surgery success group and failure group based on the criterion of whether a complete tympanic membrane was formed by endoscopic examination within 3 months.The RFS scores of the two groups were statistically analyzed.RESULTS A total of 135 patients with an average age of 44.78 years(±12.22 years)took part in this study,with 60 males and 75 females included,and 68 left ears and 67 right ears involved.There were 120 patients in the surgery success group,and 15 patients in the failure group.Statistical analysis revealed that the RFS score of the patients in the tympanoplasty failure group was remarkably higher than that of the patients in the tympanoplasty success group.Moreover,there were significantly more cases with suspected reflux pharyngitis in the surgery failure group(P=0.007).Reflux-induced tympanic membrane lesion and reperforation mostly occurred in the central part of the tympanic membrane graft.CONCLUSION Reflux pharyngitis has been implicated with tympanoplasty failure,and thus may be a causative factor.Additionally,the RFS can be used to screen patients with chronic suppurative otitis media for suspected reflux pharyngitis.Findings from this work indicate that perioperative anti-reflux therapy,combined with dietary and lifestyle counselling for the patients who suffer from reflux pharyngitis and are about to undergo the tympanoplasty surgery may improve surgical success rate.

Objective To establish a human luminal breast cancer stem cell(BCSC)model and investigate the inhibitory effects of astragaloside Ⅳ(AS-Ⅳ)on BCSC growth.Methods MCF-7 breast cancer cells were cultured in stem cell-specific medium to induce BCSC formation.The BCSCs were then divided into a blank control group and an AS-Ⅳ treatment group,both groups were given PBS or AS-Ⅳ treatment.Morphological changes were observed after intervention.The therapeutic efficacy of AS-Ⅳ was evaluated using 3D spheroid formation and cell viability assays.Transcriptomic profiling and gene expression analysis were performed to elucidate the underlying mechanisms.Results Compared with the MCF7 breast cancer cells,MCF7 breast cancer stem cell mammospheres exhibited accelerated growth(P＜0.01)and significantly increased expression of the stemness marker ALDH1A1(P＜0.01).Further comparison with the blank control group revealed that astragaloside Ⅳ(AS-Ⅳ)treatment significantly inhibited MCF7 breast cancer stem cell proliferation(P＜0.001)and slowed mammosphere growth(P＜0.01).Transcriptomic analysis demonstrated that differentially expressed genes(DEGs)induced by stem cell modeling and AS-Ⅳ intervention were enriched in the cellular senescence signaling pathway.AS-Ⅳ intervention substantially increased the number of SA-β-gal-positive cells(P＜0.01).RT-PCR analysis confirmed that AS-Ⅳsignificantly upregulated mRNA expression of IL-1α(P＜0.01),P21(P＜0.001),and P53(P＜0.05)in MCF7 breast cancer stem cells.Conclusion Astragaloside Ⅳ suppresses the growth of human luminal breast cancer stem cells by inducing cellular senescence.

Objective:To investigate the effects of fibroblast growth factor receptor 1(FGFR1)on the resistance of colorectal cancer(CRC)cells to oxaliplatin(OXA).Methods:An OXA-resistant cell line(HCT8/OXA)was established by treating HCT8 CRC cells with low-dose OXA for a long period in vitro.The CCK-8 assay was used to compare the viability of the HCT8 and HCT8/OXA cells after OXA treatment and to exam-ine their resistance to the anticancer drug.Second-generation high-throughput sequencing technology was used to identify differentially ex-pressed genes between the parental and drug-resistant cells.The expression of FGFR1 in the HCT8 and HCT8/OXA cells was detected by Western blot assay.Colony formation and flow cytometric assays were used to determine cell proliferation and apoptosis,respectively.The expression of PI3K/AKT signaling pathway-related proteins was detected using Western blot assay.Results:Compared with the levels in the HCT8 cells,the FGFR1 levels were significantly increased in the HCT8/OXA cells(P<0.01).FGFR1 overexpression in the HCT8 cells increased their drug resistance(P<0.01)and proliferation(NC+OXA:236.67±6.24;FGFR1+OXA:568.33±6.24)and decreased their apoptotic rate after OXA treatment(NC+OXA:27.83±0.85;FGFR1+OXA:17.47±1.25).FGFR1 knockdown in the HCT8/OXA cells reduced their drug resistance(P<0.01)and proliferative ability(Si-NC+OXA:411±8.29;Si-FGFR1+OXA:233.33±20.55)and increased their apoptotic rate(Si-NC+OXA:2.85±0.17;Si-FGFR1+OXA:14.42±0.77).FGFR1 inhibited the activity of the PI3K/AKT signaling pathway and cell apoptosis and improved the proliferation and drug resistance of the CRC cells.By contrast,an activator of the PI3K/AKT pathway blocked the effects of FGFR1 on this sig-naling pathway and drug resistance in the CRC cells.Conclusions:FGFR1 can inhibit the PI3K/AKT signaling pathway and thereby reduce the sensitivity of CRC cells to OXA.

Objective:To explore the clinical value of computed tomography(CT)with three-dimensional(3D)reconstruction technique in diagnosis and selecting surgical methods for patients with pituitary tumor.Methods:A retrospective analysis was performed on the clinical data of 82 elderly patients with suspected pituitary tumor at Huanggang Central Hospital between January 2021 and December 2023.All of patients underwent CT examination with 3D reconstruction technique and MRI examination.The postoperatively pathological results were used as the golden standard to compare the diagnostic results and efficiency of CT with 3D reconstruction technique and MRI for pituitary tumor.The differences of the two examination methods were compared in images quality.The clinical value of CT with 3D reconstruction technique for the selection of surgical method was further analyzed.Results:In 82 elderly patients with suspected pituitary tumor,56 cases were confirmed by postoperatively pathological examination,and 49 cases were confirmed by CT with 3D reconstruction technique,and 60 cases were confirmed by MRI.The characteristics of CT imaging were:quasi-circular or circular tumors were the majority,which had clear boundaries,and tumors grew to the side of sella turcica and around of the sella turcica,which accompanied by enlarged pituitary fossa.MRI imaging characteristics of pituitary tumors were as follows:the most of them accompanied with equal T1 and slightly high T2 signals,and there was enhancement of obvious ring,and the snowman sign.There was no significant difference in diagnostic accuracy between CT with 3D reconstruction technique and MRI(P>0.05).The diagnostic specificity of CT with 3D reconstruction technique was 96.15%,which was higher than 76.92%of MRI,while its sensitivity was 85.71%,which was lower than 96.43%of MRI,and the differences were statistically significant(x2=4.413,3.953,P<0.05).There were no significant differences in the maximum transverse diameter and maximum vertical diameter of tumors between CT with 3D reconstruction technique and MRI(P>0.05).Compared with the results of CT with 3D reconstruction technique,all of 56 patients with pituitary tumor adopted resection for pituitary tumor through nasal sphenoid approach.After surgery,2 cases occurred diabetes insipidus,and 1 case occurred intracranial infection and 1 case occurred decline in olfactory function.Conclusion:Both CT with 3D reconstruction technique and MRI have higher diagnostic value for pituitary tumors in the elderly,which can display characteristics of pituitary tumors,and have direct guidance roles for the selection of surgical methods.The diagnostic specificity of CT with 3D reconstruction technique is better.

Objective:To compare the protective effects of the static cold storage (SCS) and normothermic machine perfusion (NMP) on the skeletal muscle of the amputated limbs of pigs.Methods:Four Landrace pigs were selected, from which eight limbs were amputated and divided into SCS group ( n=5) and NMP group ( n=3) according to the random number table method. After blood collection from the carotid artery, an amputated limb model was established by amputating the limbs at the scapulohumeral joints. The limbs in the SCS group were wrapped in sterile cloth and stored at 4 ℃ for 24 hours. In the NMP group, the limbs were mechanically perfused with a red blood cell-containing perfusion fluid at 37 ℃ for 24 hours, with 70% of the perfusion fluid replaced every 6 hours. Before the experiment, cross-matching tests with the saline medium were conducted between donor and recipient pigs to evaluate blood coagulation and blood safety in the NMP group. An allogeneic red blood cell perfusion fluid was prepared and the levels of pH, Na +, K +, Cl -, Ca 2+, glucose (Glu), hematocrit (Hct), lactic acid (Lac) and osmotic pressure of the perfusion fluid were measured. At 0, 6, 12, 18, and 24 hours after perfusion, the skin temperature and oxyhemoglobin saturation (SaO 2) levels in the NMP group were monitored and the levels of pH, Glu, creatine kinase (Ck), K +, Ca 2+, and Na +levels of the perfusion fluid were analyzed to evaluate the metabolism of the skeletal muscle in the amputated limbs. The mean intercellular distance and apoptosis index of the myocytes were quantitatively analyzed and histopathological changes were observed by performing HE staining and TUNEL staining on the skeletal muscle of the amputated limbs in both groups at 0 and 24 hours after perfusion. After perfusion was ended, the weight gain rate and swelling degree of the amputated limbs were compared between the two groups and the overall state of the amputated limbs was evaluated. Results:The result of the cross-matching test between donor and recipient pig blood was negative. The parameters in the prepared red blood cell-containing perfusion fluid generally maintained within a normal range: pH 7.38±0.04, Na + concentration (138.30±4.48)mmol/L, K + concentration (3.50±0.26)mmol/L, Glu concentration (6.11±2.08)mmol/L, and osmotic pressure (305.67±3.79)mmol/L. However, slightly higher Cl - and Ca 2+ concentrations [(118.34±12.00)mmol/L and (2.00±0.15)mmol/L] and lower Hct and lactate concentrations [0.30±0.03 and (1.54±0.38)mmol/L] were detected when compared with the reference range. During the perfusion, the average skin temperature of the amputated limbs in the NMP group was (36.13±0.98)℃, with the skin temperatures at 6, 12, 18, and 24 hours after perfusion being significantly higher than that at 0 hour ( P<0.01), while no significant difference among the skin temperatures at 6, 12, 18, and 24 hours after perfusion was observed ( P>0.05). The SaO 2 levels in the skin of the amputated limbs in the NMP group averaged over 95%, which showed no significant difference at 0, 12, 18, and 24 hours after perfusion ( P>0.05), while a significant elevation was observed at 6 hours compared with that at 0 hour ( P<0.05). There were no significant differences in pH, Glu, Na +, and Ca 2+ levels in the NMP group at 0, 6, 12, 18, and 24 hours after perfusion ( P>0.05), while the Ck levels at 18 and 24 hours were both significantly higher than that at 6 hours after perfusion ( P<0.05), and the Ck levels at 6, 12, 18, and 24 hours were all significantly higher than that at 0 hour ( P<0.05). The K + level progressively increased with the perfusion time, with significant elevations at 18 and 24 hours after perfusion compared with that at 0 hour ( P<0.05). HE staining revealed well-preserved muscle fiber continuity and regular arrangement in the NMP group and the SCS group at 0 hour, with an intercellular distance of (8.95±0.60)μm. At 24 hours, the NMP group exhibited slight skeletal muscle fiber rupture and swelling, with a slightly increased intercellular distance of (14.75±0.90)μm, significantly greater than that at 0 hour ( P<0.01). At 24 hours, the SCS group showed marked skeletal muscle fiber rupture and swelling, with a significantly increased intercellular distance of (23.51±1.49)μm, significantly larger than those at 0 hour in the same group and at 24 hours in the NMP group ( P<0.01). TUNEL immunofluorescence staining indicated a tiny amount of apoptotic cells in the skeletal muscle in both groups at 0 hour, with an apoptotic index of (4.26±1.62)%. There was a small number of apoptotic cells in the skeletal muscle in the NMP group at 24 hours, with an apoptotic index of (25.94±2.69)%, significantly larger than that in the same group at 0 hour ( P<0.01). The SCS group exhibited a large number of apoptotic cells at 24 hours, with an apoptotic index of (62.97±3.22)%, significantly larger than those at 0 hour in the same group and at 24 hours in the NMP group ( P<0.01). In comparison with the SCS group at 24 hours, the amputated limbs in the NMP group showed red color in the appearance, no symptoms of ischemic muscle contracture and good joint movement despite slight edema in the subcutaneous layer. At 24 hours, the weight gain rate of the amputated limbs was (15.82±0.89)% in the NMP group, significantly higher than (0.97±0.28)% in the SCS group ( P<0.01). Conclusion:Compared with SCS, NMP with the red blood cell-containing perfusion fluid prepared with the allogeneic blood for the amputated limbs of pigs can alleviate the ischemic injury of the muscle fibers and inhibit the apoptosis of the muscle cells by sustaining stable energy and oxygen supply and balancing ion homeostasis and pH of the perfusion fluid.

Objective To evaluate the clinical outcome of neurosurgical robot-assisted stereotactic puncture and drainage for brain abscess.Methods A retrospective analysis was conducted on the clinical data of 53 patients with brain abscess admitted to our hospital from January 2018 to December 2024.Among them,29 cases underwent craniotomy for abscess resection(craniotomy group),while 24 cases received neurosurgical robot-assisted stereotactic puncture and drainage(robot-assisted group).The operation time,intraoperative blood loss,decompressive craniectomy rate,proportion of postoperative antibiotic regimen adjustment,postoperative hospital stay,incidence of postoperative complications,mortality rate and Glasgow outcome scale(GOS)scores 6 months after surgery of patients were compared between the two groups.Results Compared with the craniotomy group,the robot-assisted group demonstrated significantly shorter operation time,less intraoperative blood loss,and lower incidence of postoperative complication,the differences were all statistically significant(P<0.05).However,there were no statistically significant differences in terms of decompressive craniectomy rate,postoperative hospital stay,mortality rate,GOS score,or proportion of the postoperative antibiotic regimen adjustment between the two groups(P>0.05).Conclusion As a precise and minimally invasive surgical method,neurosurgical robot-assisted stereotactic puncture and drainage for patients with brain abscess can effectively improve the operational efficiency,shorten the operation time,reduce intraoperative injury,and lower the risk of postoperative complications.It has high clinical application value and potential for widespread adoption.

Objective:To compare the ecchymosis of affected limb in the prevention of deep vein thrombosis using low molecular weight heparin sodium and enoxaparin sodium after total knee arthroplasty.Methods:A total of 160 patients (31 males and 129 females) who underwent unilateral knee replacement in Department of Orthopedics of Chengdu Second People's Hospital from Oct. 2020 to Dec. 2023 were included. According to the random number method, all patients were evenly divided into the low molecular weight heparin sodium group (16 males and 64 females) and the enoxaparin sodium group (15 males and 65 females). All patients were treated with low molecular weight heparin sodium or enoxaparin sodium to prevent deep vein thrombosis in the lower limbs after surgery. The ecchymosis area on the affected limb was observed 7 days after surgery, and the incidence and difference in ecchymosis area between the two groups of patients were statistically analyzed. Simultaneously evaluate whether there are differences in hemoglobin, platelet, and coagulation related indicators between the two groups of patients before and after surgery.Results:There were no significant differences in hemoglobin, platelet, and coagulation parameters between the low molecular weight heparin sodium group and the enoxaparin sodium group before and after surgery ( t=1.13, -0.27, -0.47, 0.27, 0.34, -0.27, -0.89, -0.46, P=0.27, 0.34, 0.64, 0.83, 0.74, 0.97, 0.24, 0.65). The incidence of ecchymosis in patients with low molecular weight heparin sodium group and enoxaparin sodium group was 61.25% and 67.50%, respectively, with no statistically significant difference in the incidence of ecchymosis between the two groups ( P=0.41). The average size of ecchymosis in the two groups of patients was (40.40 ± 60.07) cm 2 and (37.41 ± 43.21) cm 2, respectively. And there was no statistically significant difference in ecchymosis area ( P=0.61) . Conclusion:Both patients had limbs’ecchymosis in the process of preventing deep venous thrombosis of lower limbs after total knee replacement. This indicates that the two anticoagulants had a certain effect on postoperative skin ecchymosis of total knee. And the incidence rate and area of ecchymosis of affected limbs were similar in the two groups.