This study aims to investigate the anti-tumor effect and mechanism of Guiqi Yiyuan Ointment combined with cisplatin on Lewis lung carcinoma-bearing mice via the protein kinase RNA-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2α(eIF2α)/activated transcription factor 4(ATF4)/C/EBP homologous protein(CHOP) signaling pathway. Sixty SPF-grade male C57BL/6 mice were selected and assigned into a blank group and a modeling group by the random number table method. After modeling of the Lewis lung carcinoma, the mice in the modeling group were randomized into model, cisplatin(5 mg·kg~(-1), once a week), and low-, medium-, and high-dose(1.7, 3.5, and 7.05 g·kg~(-1), respectively, once a day) Guiqi Yiyuan Ointment+cisplatin(5 mg·kg~(-1)) groups(n=10). After 14 days of continuous intervention, the spleen, thymus, and tumor samples of the mice were collected, weighed, and recorded, and the spleen index, thymus index, and tumor suppression rate were calculated. Hematoxylin-eosin(HE) staining was employed to observe the pathological changes in the tumor tissue. The morphological changes of the endoplasmic reticulum of tumor cells were observed by transmission electron microscopy. The positive expression of phosphorylated eIF2α(p-eIF2α) and ATF4 in the tumor tissue was detected by immunofluorescence. Western blot was employed to determine the protein levels of phosphorylated PERK(p-PERK), p-eIF2α, ATF4, CHOP, B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), cyclin-dependent kinase inhibitor 1A(p21), and cyclinD1 in the tumor tissue. Real-time fluorescent quantitative PCR was employed to determine the mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, Bcl-2, p21, and cyclinD1 in the tumor tissue. Compared with the blank group, the model group showed decreases in spleen index and thymus index(P<0.05). Compared with the model group, the cisplatin group showed decreases in spleen index and thymus index(P<0.05), and the medium-and high-dose Guiqi Yiyuan Ointment+cisplatin groups presented increases in spleen index and thymus index(P<0.05). In addition, the treatment groups all showed decreased tumor mass(P<0.05), increased tumor cell lysis and nuclear rupture, widened gap between rough endoplasmic reticulum, enhanced average fluorescence intensity of p-eIF2α and ATF4(P<0.05), up-regulated protein levels of p-PERK/PERK, p-eIF2α/eIF2α, ATF4, CHOP, Bax, and p21(P<0.05), down-regulated protein and mRNA levels of Bcl-2 and cyclinD1(P<0.05), and up-regulated mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, and p21(P<0.05). Compared with the cisplatin group, the combination groups showed increases in spleen index and thymus index(P<0.05) as well as mean optical density(P<0.05), and the high-dose Guiqi Yiyuan Ointment+cisplatin group showed decreased tumor mass(P<0.05). In addition, the medium-and high-dose Guiqi Yiyuan Ointment+cisplatin groups showcased enhanced average fluorescence intensity of p-eIF2α and ATF4(P<0.05), up-regulated protein levels of p-PERK/PERK, p-eIF2α/eIF2α, ATF4, CHOP, Bax, and p21(P<0.05), down-regulated protein and mRNA levels of Bcl-2 and cyclinD1(P<0.05), and up-regulated mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, and p21(P<0.05). In conclusion, Guiqi Yiyuan Ointment combined with cisplatin can effectively inhibit the growth of Lewis lung carcinoma in mice by regulating the expression of proteins related to the PERK/eIF2α/ATF4/CHOP signaling pathway and promoting cell cycle arrest and apoptosis.
Animals ; Cisplatin/administration & dosage* ; Activating Transcription Factor 4/genetics* ; Eukaryotic Initiation Factor-2/genetics* ; eIF-2 Kinase/genetics* ; Carcinoma, Lewis Lung/pathology* ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Mice ; Signal Transduction/drug effects* ; Mice, Inbred C57BL ; Transcription Factor CHOP/genetics* ; Ointments/administration & dosage* ; Humans ; Cell Proliferation/drug effects* ; Antineoplastic Agents/administration & dosage*

As a new type of production factor that can empower the development of new quality productivity, the data element is an important engine to promote the high quality development of the industry. Traditional Chinese medicine(TCM) dispensing is the most basic work of TCM clinical pharmacy, and its quality directly affects the clinical efficacy of TCM. The integration of data elements and TCM dispensing can stimulate the innovation and vitality of the TCM dispensing industry and promote the high-quality and sustainable development of the industry. A large-scale, detailed, and systematic study on TCM dispensing was conducted. The innovative practice path of data fusion construction in the whole process of TCM dispensing was investigated by integrating the digital resources "nine full activities" of TCM dispensing, creating the digital dictionary of "TCM clinical information data elements", and exploring innovative applications of TCM dispensing driven by data and technology, so as to promote the standardized, digital, and intelligent development of TCM dispensing in medical health services. The research content of this project was successfully selected as the second batch of "Data element×" typical cases of National Data Administration in 2024, which is the only selected case in the field of TCM.
Medicine, Chinese Traditional/methods* ; Drugs, Chinese Herbal ; Humans

OBJECTIVE: To reveal the molecular basis of knee osteoarthritis (KOA) with Yang deficiency and blood stasis syndrome by analyzing the gene expression profiles in synovial fluid and blood of KOA patients with this syndrome. METHODS: A total of 80 KOA patients were recruited from October 2022 to June 2024, including 40 cases in the non-Yang deficiency and blood stasis group (27 males and 13 females), with an average age of (61.75±3.45) years old;and 40 cases in the Yang deficiency and blood stasis group (22 males and 18 females), with an average age of (62.00±2.76) years old. The levels of body mass index (BMI), high-density lipoprotein (HDL), low-density lipoprotein (LDL), fibrinogen, total cholesterol, and D-dimer were recorded and summarized. Blood and synovial fluid samples from patients were collected for gene expression profile microarray sequencing, and then PCR and immunohistochemistry were used for clinical verification on the patients' synovial fluid and cartilage samples. RESULTS: Logistic regression analysis showed that compared with KOA patients with non-Yang deficiency and blood stasis syndrome, those with Yang deficiency and blood stasis syndrome had increased BMI, LDL, fibrinogen, total cholesterol, and D-dimer, and decreased HDL, with a clear correlation between the two groups. There were 562 differential genes in the blood, among which 322 were up-regulated and 240 were down-regulated;755 differential genes were found in the synovial fluid, with 350 up-regulated and 405 down-regulated. KEGG signaling pathway analysis of synovial fluid revealed changes in lipid metabolism-related pathways, including cholesterol metabolism, fatty acid metabolism, and PPARG signaling pathway. Analysis of the involved differential genes identified 6 genes in synovial fluid that were closely related to lipid metabolism, namely LRP1, LPL, ACOT6, TM6SF2, DGKK, and PPARG. Subsequently, PCR and immunohistochemical verification were performed using synovial fluid and cartilage samples, and the results were consistent with those of microarray sequencing. CONCLUSION This study explores the clinical and genomic correlation between traditional Chinese medicine syndromes and knee osteoarthritis from the perspective of lipid metabolism, and proves that abnormal lipid metabolism is closely related to KOA with Yang deficiency and blood stasis syndrome from both clinical and basic aspects.
Humans ; Male ; Female ; Middle Aged ; Synovial Fluid/metabolism* ; Osteoarthritis, Knee/metabolism* ; Yang Deficiency/complications* ; Aged

OBJECTIVE: To observe the clinical symptoms and MRI outcomes of patients with ruptured lumbar disc herniation(LDH) through a multicenter randomized controlled study, and to evaluate the clinical efficacy and safety of Yiqi Huoxue formula() in the treatment of this disease. METHODS: A total of 160 outpatients and inpatients with ruptured LDH admitted to 4 medical centers from January 2023 to June 2023 were selected and randomly divided into the Yiqi Huoxue formula group and the control group, with 80 patients in each group. In the Yiqi Huoxue formula group, there were 43 males and 37 females, with an age of (41.03±9.56) years and a disease duration of (10.45±25.37) days, and the patients were treated with Yiqi Huoxue formula. In the control group, there were 34 males and 46 females, with an age of (42.14±8.73) years and a disease duration of (11.31±21.14) days;during the acute phase, patients in this group could take celecoxib capsules orally, and methylcobalamin orally at the same time. The Japanese Orthopaedic Association (JOA) score, Oswestry disability index (ODI), changes in the volume of herniated disc tissue on MRI, herniation rate, and absorption rate were recorded at the time of enrollment and during follow-ups at the 3rd, 6th, and 12th month after treatment. RESULTS: A total of 156 patients completed the clinical follow-up, and 4 patients withdrew midway. The clinical symptoms of all patients who completed the study were relieved to varying degrees, and reabsorption of herniated disc tissue was observed in all patients in the Yiqi Huoxue formula group after treatment. For the JOA score:in the Yiqi Huoxue formula group, it was (10.73±2.76) points before treatment and (24.65±2.19) points at the 12th month after treatment;in the control group, it was (11.01±1.20) points before treatment and (17.07±3.26) points at the 12th month after treatment. For the ODI score:in the Yiqi Huoxue formula group, it was (26.21±3.55) points before treatment and (5.65±2.19) points at the 12th month after treatment;in the control group, it was (27.92±2.51) points before treatment and (9.09±2.15) points at the 12th month after treatment. At the 12th month after treatment, the JOA and ODI scores of both groups were better than those before treatment, and the scores of the Yiqi Huoxue formula group were better than those of the control group, with statistically significant differences (P<0.05). In terms of the herniated disc volume and herniation rate on MRI, the Yiqi Huoxue formula group was superior to the control group, with statistically significant differences(P<0.05). Reabsorption occurred in 56.96%(45/79) of patients in the Yiqi Huoxue formula group, which was significantly higher than the 37.66%(29/77) in the control group. CONCLUSION After treatment with Yiqi Huoxue formula, patients with ruptured LDH show significant improvement in clinical symptoms and a marked reduction in the volume of herniated discs. During the follow-up period, no obvious adverse drug reactions are observed in patients, and no recurrence of symptoms is found at the last follow-up, indicating that the formula has safe and reliable efficacy.
Humans ; Male ; Female ; Intervertebral Disc Displacement/drug therapy* ; Adult ; Drugs, Chinese Herbal/adverse effects* ; Middle Aged ; Lumbar Vertebrae

OBJECTIVE: To investigate the effect of 5-hydroxytryptamine (5-HT) on the proliferation, apoptosis and colony-forming unit-megakaryocyte (CFU-MK) of Meg-01 cells and its possible mechanisms. METHODS: The uptake and metabolism of 5-HT in Meg-01 cells were analysed by reverse-phase high-performance liquid chromatography (RP-HPLC) with electrochemical detection. The expression of 5-HT2B receptor (5-HT2BR) in megakaryocytes was detected by immunofluorescence staining. The cell proliferation and viability were measured by MTT and Trypan blue staining after Meg-01 cells were single-cultured or co-cultured with different concentrations of 5-HT/5-HT2BR inhibitor Ketanserin for 48 h. Meg-01 cells were incubated with 5-HT/ Ketanserin for 72 h, then the flow cytometry was used to detect early apoptosis of the cells and the activity of caspase-3. Using CFU-MK assay to investigate the effect of 5-HT on the differentiation of megakaryocytes. RESULTS: 5-HT could be uptaken by Meg-01 cells, and metabolized into 5-hydroxyindoleacetic acid (5-HIAA). The expression of 5-HT2BR on megakaryocytes could be detected after immunofluorescence staining. 5-HT could promote the proliferation of Meg-01 cells at a dose-dependent manner (r =0.82), with the most significant effect observed at a concentration of 200 nmol/L (P < 0.001). Trypan blue staining also indicated that 200 nmol/L 5-HT had the most significant effect on the viability of Meg-01 cells (P < 0.05). The proliferation of Meg-01 cells treated with 5-HT was increased compared with the untreated control (P < 0.001), while the combination of 5-HT with ketanserin downregulated this effect. 5-HT significantly reduced the early apoptosis rate (P < 0.001) and caspase-3 activity (P < 0.05) of Meg-01 cells, while addition of ketanserin significantly increased the early apoptosis rate of Meg-01 cells (P < 0.001) and caspase-3 activity also increased to some extent. 5-HT promoted the formation of CFU-MK in bone marrow cells in a dose-dependent manner (r =0.89). The addition of ketanserin reduced the promoting effect of 5-HT on CFU-MK formation (P < 0.01). CONCLUSION There may be monoamine oxidase present in megakaryocytes, which can metabolize and decompose 5-HT into 5-HIAA. 5-HT may promote the proliferation and differentiation of megakaryocytes through 5-HT2BR. Besides, 5-HT can also reduce the apoptosis of megakaryocytes, and its anti-apoptotic effect may be mediated by 5-HT2BR and caspase-3 pathways.
Apoptosis/drug effects* ; Cell Proliferation/drug effects* ; Megakaryocytes/metabolism* ; Serotonin/pharmacology* ; Humans ; Receptor, Serotonin, 5-HT2B/metabolism* ; Caspase 3/metabolism* ; Cell Differentiation

OBJECTIVE: To investigate lymph node metastasis (LNM) in the prostatic anterior fat pad (PAFP) of PCa patients after robot-assisted radical prostatectomy (RARP), and analyze the clinicopathological features and prognosis of LNM in the PAFP. METHODS: We retrospectively analyzed the clinicopathological data on 1 003 cases of PCa treated by RARP in the Department of Urology of PLA General Hospital from January 2017 to December 2022. All the patients underwent routine removal of the PAFP during RARP and pathological examination, with the results of all the specimens examined and reported by pathologists. Based on the presence and locations of LNM, we grouped the patients for statistical analysis, compared the clinicopathological features between different groups using the Student's t, Mann-Whitney U and Chi-square tests, and conducted survival analyses using the Kaplan-Meier and Log-rank methods and survival curves generated by Rstudio. RESULTS: Lymph nodes were detected in 77 (7.7%) of the 1 003 PAFP samples, and LNM in 11 (14.3%) of the 77 cases, with a positive rate of 1.1% (11/1 003). Of the 11 positive cases, 9 were found in the upgraded pathological N stage, and the other 2 complicated by pelvic LNM. The patients with postoperative pathological stage≥T3 constituted a significantly higher proportion in the PAFP LNM than in the non-PAFP LNM group (81.8% ［9/11］ vs 36.2% ［359/992］, P = 0.005), and so did the cases with Gleason score ≥8 (87.5% ［7/8］ vs 35.5% ［279/786］, P = 0.009). No statistically significant differences were observed in the clinicopathological features and biochemical recurrence-free survival between the patients with PAFP LNM only and those with pelvic LNM only. CONCLUSION The PAFP is a potential route to LNM, and patients with LNM in the PAFP are characterized by poor pathological features. There is no statistically significant difference in biochemical recurrence-free survival between the patients with PAFP LNM only and those with pelvic LNM only. Routine removal of the PAFP and independent pathological examination of the specimen during RARP is of great clinical significance.
Humans ; Male ; Prostatectomy/methods* ; Robotic Surgical Procedures ; Lymphatic Metastasis ; Retrospective Studies ; Prognosis ; Prostatic Neoplasms/pathology* ; Adipose Tissue/pathology* ; Prostate/pathology* ; Lymph Nodes/pathology* ; Middle Aged ; Aged

Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Background::Bladder cancer, characterized by a high potential of tumor recurrence, has high lifelong monitoring and treatment costs. To date, tumor cells with intrinsic softness have been identified to function as cancer stem cells in several cancer types. Nonetheless, the existence of soft tumor cells in bladder tumors remains elusive. Thus, our study aimed to develop a microbarrier microfluidic chip to efficiently isolate deformable tumor cells from distinct types of bladder cancer cells.Methods::The stiffness of bladder cancer cells was determined by atomic force microscopy (AFM). The modified microfluidic chip was utilized to separate soft cells, and the 3D Matrigel culture system was to maintain the softness of tumor cells. Expression patterns of integrin β8 (ITGB8), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) were determined by Western blotting. Double immunostaining was conducted to examine the interaction between F-actin and tripartite motif containing 59 (TRIM59). The stem-cell-like characteristics of soft cells were explored by colony formation assay and in vivo studies upon xenografted tumor models. Results::Using our newly designed microfluidic approach, we identified a small fraction of soft tumor cells in bladder cancer cells. More importantly, the existence of soft tumor cells was confirmed in clinical human bladder cancer specimens, in which the number of soft tumor cells was associated with tumor relapse. Furthermore, we demonstrated that the biomechanical stimuli arising from 3D Matrigel activated the F-actin/ITGB8/TRIM59/AKT/mTOR/glycolysis pathways to enhance the softness and tumorigenic capacity of tumor cells. Simultaneously, we detected a remarkable up-regulation in ITGB8, TRIM59, and phospho-AKT in clinical bladder recurrent tumors compared with their non-recurrent counterparts.Conclusions::The ITGB8/TRIM59/AKT/mTOR/glycolysis axis plays a crucial role in modulating tumor softness and stemness. Meanwhile, the soft tumor cells become more sensitive to chemotherapy after stiffening, that offers new insights for hampering tumor progression and recurrence.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To investigate the role of oxidative stress and silent information regulator 2 homolog 1 (SIRT1) in cartilage injury in Kashin-Beck disease (KBD) by evaluating the level of oxidative stress and the effect of oxidative injury on SIRT1 expression in patients with KBD.Methods:In May 2017, Twenty patients with KBD were selected from Guide County of Qinghai Province as the KBD group, and 40 healthy subjects were selected as the control group, 5 ml elbow venous blood was collected, centrifuged, and the upper plasma was retained. The glutathione peroxidase (GPX) activity and reactive oxygen species (ROS) level were determined by enzyme linked immunosorbent assay (ELISA), and SIRT1 mRNA level was determined by real-time fluorescence quantitative PCR (RT-qPCR). Meanwhile, 150 μmol/L tert-butyl hydroperoxide (tBHP) was selected to damage chondrocytes; and different concentrations of sodium selenite (Na 2SeO 3) were used to intervene in chondrocytes to detect cell viability, and appropriate concentration of Na 2SeO 3 was selected for pre protection. Total RNA and DNA of chondrocytes were extracted. The mRNA levels of SIRT1, DNA methyltransferase 1 (DNMT1), and the DNA methylation level in the SIRT1 promoter region were determined by RT-qPCR. At the same time, Hoechst 33342 staining was used to detect chondrocyte apoptosis. Results:The plasma GPX activity [(35.48 ± 8.82) U/g·Hb] in KBD group was lower than that in control group [(40.43 ± 6.68) U/g·Hb, t = - 2.43, P = 0.018], and the ROS level [(577.10 ± 96.92) U/ml] was higher than that in control group [(526.44 ± 62.63) U/ml, t = 2.13, P = 0.043]. GPX activity was positively correlated with SIRT1 mRNA level ( r s = 0.44, P = 0.005), while ROS level was negatively correlated with SIRT1 mRNA level ( r s = - 0.39, P = 0.006). After 48 hours of treatment with 150 μmol/L tBHP (tBHP injury group), the survival rate of chondrocytes decreased to (55.27 ± 2.96)%; and the survival rate of chondrocytes pre-protected with 0.10 μg/ml Na 2SeO 3 (selenium protection group) was significantly higher than that of tBHP injury group ( P < 0.05). Compared with control group, the SIRT1 mRNA level of chondrocytes in tBHP injury group was significantly decreased; while the DNA methylation level in the SIRT1 promoter region, DNMT1 mRNA level and cell apoptosis rate were significantly increased ( P < 0.05). Compared with tBHP injury group, the selenium protection group had higher levels of SIRT1 mRNA in chondrocytes, lower levels of DNA methylation in the SIRT1 promoter region, DNMT1 mRNA, and cell apoptosis rate ( P < 0.05). The apoptosis rate was negatively correlated with SIRT1 mRNA level ( r s = - 0.78, P = 0.004), and positively correlated with the DNA methylation level in the SIRT1 promoter region ( r s = 0.76, P = 0.006). Conclusions:KBD patients have increased levels of oxidative stress, which may be associated with low expression of SIRT1. Oxidative injury may down-regulate SIRT1 expression and promote chondrocytes apoptosis by catalyzing DNA methylation in the SIRT1 promoter region.