Reactive oxygen species(ROS)are common products of bone tissue injury.If ROS cannot be removed in time,oxidative stress will be induced in the cells,which will have a negative effect on the regeneration of bone tissue.In recent years,with the deepening of research,nanomaterials capable of reducing ROS levels have shown increasing potential in promoting bone tissue regeneration.Currently,nanomaterials applied to reduce ROS levels mainly include those with surface modifications and microstructural designs,dopant-modified inorganic materials,functionalized polymeric materials and hydrogels,and nano-enzymatic materials.However,the clinical application of these nanomaterials is still limited due to their potential cytotoxicity and the lack of sufficient clinical trials.This literature review summarises the research on the use of nanomaterials to reduce ROS levels to promote bone regeneration and provides ideas for the future design and development of novel nanomaterials in this field.

Reactive oxygen species(ROS)are common products of bone tissue injury.If ROS cannot be removed in time,oxidative stress will be induced in the cells,which will have a negative effect on the regeneration of bone tissue.In recent years,with the deepening of research,nanomaterials capable of reducing ROS levels have shown increasing potential in promoting bone tissue regeneration.Currently,nanomaterials applied to reduce ROS levels mainly include those with surface modifications and microstructural designs,dopant-modified inorganic materials,functionalized polymeric materials and hydrogels,and nano-enzymatic materials.However,the clinical application of these nanomaterials is still limited due to their potential cytotoxicity and the lack of sufficient clinical trials.This literature review summarises the research on the use of nanomaterials to reduce ROS levels to promote bone regeneration and provides ideas for the future design and development of novel nanomaterials in this field.

Objective:To evaluate the safety and efficacy of a dual-endoscopic technique combining laparoscopy/robot-assisted laparoscopy with disposable flexible ureteroscopy for intraoperative localization and reconstruction in complex ureteral strictures.Methods:A retrospective analysis was conducted on 21 patients with complex ureteral strictures(stenosis length ≥2 cm,multiple strictures,or iatrogenic stric-tures,or radiation-induced strictures)treated at Peking University People's Hospital between January 2023 and November 2024.All the patients underwent dual-endoscopic procedures using laparoscopy(n=17)or da Vinci robotic-assisted laparoscopy(n=4)combined with disposable flexible ureterosco-py.Preoperative evaluation included contrast-enhanced CT urography and diuretic renography.Intra-operatively,stricture localization was achieved by synchronizing laparoscopic light sources with uretero-scopic visualization.Surgical positions were optimized:non-split-leg oblique supine position for mid-upper strictures and lithotomy position for mid-lower strictures.Reconstruction strategies(lingual mucosa graft,bladder flap augmentation,or primary anastomosis)were selected based on stricture length and tension.Postoperative outcomes were assessed via symptom resolution,hydronephrosis improvement(ultrasono-graphic renal pelvis diameter),and stent-free patency.Results:The cohort included 10 males and 11 females[mean age(44.1±13.3)years].Etiologies included lithogenic strictures(71.4％,15/21),post-gynecologic surgery injury(4.8％),radiation-induced fibrosis(4.8％),and congenital factors(19.0％).Intraoperative findings revealed discrepancies in stricture localization compared with pre-operative imaging in 52.4％(11/21)of cases,necessitating extended resection or modified reconstruc-tion.Mean stricture length was(4.81±4.33)cm.Postoperative complications included transient urina-ry leakage(1 case)and secondary ureteral obstruction due to stone migration(1 case),both resolved without sequelae.At a mean follow-up of(10.76±6.81)months(range 2-21),hydronephrosis sig-nificantly improved in all the patients(100％efficacy),with no recurrence of strictures or symptom re-currence.Conclusion:The dual-endoscopic technique enhances intraoperative precision in complex ure-teral stricture management by integrating real-time luminal visualization with extraluminal anatomical guidance.This approach minimizes excessive resection of healthy ureter,optimizes reconstruction strate-gies,and reduces postoperative recurrence.The modified positioning protocol further improves ergonomic efficiency,making it a reliable and adaptable option for challenging ureteral pathologies.

Objective:To explore the related risk factors contributing to re-fracture after hip surgery in elderly patients.Methods:This retrospective analysis was conducted on the clinical data of 2 415 elderly individuals who underwent surgical treatment for hip fractures and were discharged from Shanghai Sixth People's Hospital between January 2016 and December 2021.Patients were grouped into re-fracture and non-re-fracture cohorts based on whether a second fracture occurred within three years after surgery.Demographics, clinical data, and postoperative functional rehabilitation outcomes of the two groups were collected, and univariate and multivariate logistic regression analyses were applied to identify the independent risk factors for re-fractures after surgery.Results:A total of 2, 000 patients who completed follow-up were included in the final analysis, aged 60~91 years, with a mean age of (75.4±8.2) years.Among them, 855 were male(42.75%), and the postoperative re-fracture incidence was 28.25% (565/2 000). Univariate analysis indicated that advanced age, fracture type at first onset, lower Harris scores, insufficient rehabilitation training, osteoporosis, diabetes, cerebrovascular disorders, visual impairment, and syncope were all significantly associated with re-fracture (all P<0.05), while gender differences were not statistically significant ( P>0.05). Multivariate regression confirmed the following as independent risk factors: age ≥75 years, postoperative Harris score <80, non-standard rehabilitation training, combined osteoporosis, diabetes, cerebrovascular disease, visual impairment, and syncope ( OR、 RR>1). Conclusions:Elderly patients are prone to re-fracture after hip surgery, and its occurrence is closely related to advanced age, inadequate functional rehabilitation, osteoporosis, and multiple internal medical comorbidities.In clinical practice, attention should be paid to standardized postoperative rehabilitation, systematic anti-osteoporotic therapy, and active intervention of comorbidities to reduce the incidence of re-fracture and improve the long-term prognosis of patients.

Objective:To evaluate the safety and efficacy of a dual-endoscopic technique combining laparoscopy/robot-assisted laparoscopy with disposable flexible ureteroscopy for intraoperative localization and reconstruction in complex ureteral strictures.Methods:A retrospective analysis was conducted on 21 patients with complex ureteral strictures(stenosis length ≥2 cm,multiple strictures,or iatrogenic stric-tures,or radiation-induced strictures)treated at Peking University People's Hospital between January 2023 and November 2024.All the patients underwent dual-endoscopic procedures using laparoscopy(n=17)or da Vinci robotic-assisted laparoscopy(n=4)combined with disposable flexible ureterosco-py.Preoperative evaluation included contrast-enhanced CT urography and diuretic renography.Intra-operatively,stricture localization was achieved by synchronizing laparoscopic light sources with uretero-scopic visualization.Surgical positions were optimized:non-split-leg oblique supine position for mid-upper strictures and lithotomy position for mid-lower strictures.Reconstruction strategies(lingual mucosa graft,bladder flap augmentation,or primary anastomosis)were selected based on stricture length and tension.Postoperative outcomes were assessed via symptom resolution,hydronephrosis improvement(ultrasono-graphic renal pelvis diameter),and stent-free patency.Results:The cohort included 10 males and 11 females[mean age(44.1±13.3)years].Etiologies included lithogenic strictures(71.4％,15/21),post-gynecologic surgery injury(4.8％),radiation-induced fibrosis(4.8％),and congenital factors(19.0％).Intraoperative findings revealed discrepancies in stricture localization compared with pre-operative imaging in 52.4％(11/21)of cases,necessitating extended resection or modified reconstruc-tion.Mean stricture length was(4.81±4.33)cm.Postoperative complications included transient urina-ry leakage(1 case)and secondary ureteral obstruction due to stone migration(1 case),both resolved without sequelae.At a mean follow-up of(10.76±6.81)months(range 2-21),hydronephrosis sig-nificantly improved in all the patients(100％efficacy),with no recurrence of strictures or symptom re-currence.Conclusion:The dual-endoscopic technique enhances intraoperative precision in complex ure-teral stricture management by integrating real-time luminal visualization with extraluminal anatomical guidance.This approach minimizes excessive resection of healthy ureter,optimizes reconstruction strate-gies,and reduces postoperative recurrence.The modified positioning protocol further improves ergonomic efficiency,making it a reliable and adaptable option for challenging ureteral pathologies.

Objective:To explore the related risk factors contributing to re-fracture after hip surgery in elderly patients.Methods:This retrospective analysis was conducted on the clinical data of 2 415 elderly individuals who underwent surgical treatment for hip fractures and were discharged from Shanghai Sixth People's Hospital between January 2016 and December 2021.Patients were grouped into re-fracture and non-re-fracture cohorts based on whether a second fracture occurred within three years after surgery.Demographics, clinical data, and postoperative functional rehabilitation outcomes of the two groups were collected, and univariate and multivariate logistic regression analyses were applied to identify the independent risk factors for re-fractures after surgery.Results:A total of 2, 000 patients who completed follow-up were included in the final analysis, aged 60~91 years, with a mean age of (75.4±8.2) years.Among them, 855 were male(42.75%), and the postoperative re-fracture incidence was 28.25% (565/2 000). Univariate analysis indicated that advanced age, fracture type at first onset, lower Harris scores, insufficient rehabilitation training, osteoporosis, diabetes, cerebrovascular disorders, visual impairment, and syncope were all significantly associated with re-fracture (all P<0.05), while gender differences were not statistically significant ( P>0.05). Multivariate regression confirmed the following as independent risk factors: age ≥75 years, postoperative Harris score <80, non-standard rehabilitation training, combined osteoporosis, diabetes, cerebrovascular disease, visual impairment, and syncope ( OR、 RR>1). Conclusions:Elderly patients are prone to re-fracture after hip surgery, and its occurrence is closely related to advanced age, inadequate functional rehabilitation, osteoporosis, and multiple internal medical comorbidities.In clinical practice, attention should be paid to standardized postoperative rehabilitation, systematic anti-osteoporotic therapy, and active intervention of comorbidities to reduce the incidence of re-fracture and improve the long-term prognosis of patients.

Objective·To explore the relationship between osteoarthritis and nicotinamide metabolism-related genes using bioinformatics analysis,and identify key genes with diagnostic value and therapeutic potential.Methods·By using"Osteoarthritis"as a search term,GSE12021,GSE55235,and GSE55457 were obtained from the GEO database,with GSE55457 being used as the validation set.After removing batch effects from the GSE12021 and GSE55235 datasets,the standardized combined dataset was obtained and used as the training dataset.Differentially expressed genes(DEGs)were identified from the training dataset.All nicotinamide metabolism-related genes(NMRGs)were obtained from the GeneCards and MSigDB databases.The intersection of DEGs and NMRGs was taken to obtain nicotinamide metabolism-related differentially expressed genes(NMRDEGs).Gene set enrichment analysis(GSEA)was performed on the training dataset,while gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)analysis were performed on NMRDEGs.Key genes were selected by using least absolute shrinkage and selection operator(LASSO)and support vector machine(SVM)analysis in NMRDEGs to build an osteoarthritis diagnosis model which was validated by using the GSE55457 dataset.Single sample gene set enrichment analysis(ssGSEA)was used to analyze the immune cell infiltration type.Interactions networks and drug molecule predictions were obtained for these key genes'mRNA with the DGIdb,ENCORI,and CHIPBase databases.siRNA was used to knock down the key genes in chondrocytes,and then real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)was used to detect the expression of chondrogenesis-related genes.Results·Seven NMRDEGs,including NAMPT,TIPARP,were discovered.GO and KEGG analysis enriched some signaling pathways,such as nuclear factor-κB signaling pathway and positive regulation of interleukin-1-mediated signaling pathway.GSEA enriched pathways such as Hif1 Tfpathway and syndecan 1 pathway.Key genes NPAS2,TIPARP,and NAMPT were identified through LASSO and SVM analysis,and used to construct an osteoarthritis diagnostic model.The validated results showed that the diagnostic model had high accuracy.Immune infiltration analysis results obtained by ssGSEA showed significant differences(all P<0.05)in 15 types of immune cells,including macrophages.Seven potential small molecules targeting key genes were identified,along with 19 miRNAs with the sum of upstream and downstream>10,19 transcription factors with upstream and downstream>7,and 27 RNA binding proteins with clusterNum>19.The results of RT-qPCR showed that knocking down key genes reduced the expression of chondrogenesis-related genes.Conclusion·Through bioinformatics analysis,key genes related to nicotinamide metabolism,NPAS2,TIPARP,and NAMPT,are discovered,and an osteoarthritis diagnostic model is constructed.

Metastasis of renal cell carcinoma to the contralateral testis is a rare occurrence, and we reported a case. The patient had previously undergone radical left nephrectomy for clear cell carcinoma of the left kidney. Six years postoperatively, he presented with enlargement of the right testis and subsequently underwent radical orchiectomy. The postoperative pathological results confirmed the diagnosis of metastasis from the left renal cell carcinoma to the right testis. Three months post-surgery, the patient initiated treatment with a combination of axitinib and pembrolizumab. At the last follow-up, the patient had completed five cycles of targeted and immunotherapy, and there was no evidence of recurrence or metastasis.

Metastasis of renal cell carcinoma to the contralateral testis is a rare occurrence, and we reported a case. The patient had previously undergone radical left nephrectomy for clear cell carcinoma of the left kidney. Six years postoperatively, he presented with enlargement of the right testis and subsequently underwent radical orchiectomy. The postoperative pathological results confirmed the diagnosis of metastasis from the left renal cell carcinoma to the right testis. Three months post-surgery, the patient initiated treatment with a combination of axitinib and pembrolizumab. At the last follow-up, the patient had completed five cycles of targeted and immunotherapy, and there was no evidence of recurrence or metastasis.

Objective:To investigate the clinical and pathological characteristics and prognosis of upper tract urothelial carcinoma (UTUC) with concurrent other histological variants.Methods:The clinical data of 566 UTUC patients admitted to Peking University People's Hospital from January 2007 to April 2021 were retrospectively analyzed. Among them, 289 were males and 277 were females, with an average age of (67.3±10.0)years old. Among the patients, 97 had a history of smoking, 29 had undergone kidney transplantation, 120 had diabetes, 76 had coronary heart disease, 146 had hyperlipidemia, 271 had hypertension, and 50 had a history of chronic kidney disease. Among the UTUC cases, 366 had concurrent hydronephrosis, 55 had concurrent bladder cancer, and 43 had a history of previous bladder cancer. The distribution included 210 cases of renal pelvis carcinoma, 5 cases of carcinoma at the renal pelvis-ureter junction, 226 cases of ureteral carcinoma, and 125 cases of multifocal tumors. Patients were classified into the pure UTUC group and the UTUC with concurrent other histological variants group based on postoperative pathology, and their clinical and pathological features were compared. Logistic regression analysis was used to explore risk factors for the occurrence of histological variations in UTUC. The log-rank test was employed to compare the overall survival (OS) and cancer-specific survival (CSS) between the two groups, while Cox regression analysis was performed to investigate prognostic factors.Results:Among the 566 cases, 511 were pure UTUC and 55 were UTUC with concurrent other histological variants. Among the latter, 30 cases had squamous differentiation, 6 had glandular differentiation, 5 had mucinous differentiation, 5 had sarcomatoid carcinoma, 2 had micropapillary carcinoma, 2 had neuroendocrine carcinoma, 1 had giant cell carcinoma, and 4 had other mixed histological variations. The proportion of patients with a history of kidney transplantation was higher in the UTUC with concurrent histological variants group than that in the pure UTUC group [14.5% (8/55) vs. 4.1% (21/511)], with statistically significant difference ( P=0.003). In the UTUC with concurrent histological variants group, the proportion of postoperative high-grade tumors [98.2% (54/55) vs. 80.2% (410/511)], muscle-invasive tumors [89.1% (49/55) vs. 68.1% (348/511)], lymph node metastasis tumors [10.9% (6/55) vs. 2.3% (12/511)], and maximum tumor diameter [(3.60±2.64) cm vs. (2.96±1.98) cm] were higher than those in the pure UTUC group ( P<0.05). Multivariate logistic regression analysis showed that a history of kidney transplantation ( OR=4.991, 95% CI 1.749-13.615, P=0.002) was an independent predictive factor for the occurrence of histological variants. Follow-up was conducted for 1 to 174 months, with a median follow-up time of 32.8 months. UTUC with concurrent histological variants was significantly associated with worse OS and CSS ( P<0.05). Multivariate Cox regression analysis indicated that histological variants were an independent risk factor for OS ( HR=1.860, 95% CI 1.228-2.816, P=0.003) and CSS ( HR=2.146, 95% CI 1.349-3.412, P=0.001). Conclusions:UTUC with concurrent other histological variants exhibited higher postoperative tumor grade and stage compared to pure UTUC, and UTUC with concurrent other histological variants was an independent risk factor for worse prognosis.