1.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
2.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
3.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
4.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
5.Effect of acupuncture on chondrocyte autophagy in rats of knee osteoarthritis based on PI3K/Akt/mTOR signaling pathway.
Dekun LI ; Changfeng YAO ; Ziliang SHAN ; Zheng ZHOU ; Xianji ZHANG ; Kewen WANG ; Shaolin DU
Chinese Acupuncture & Moxibustion 2025;45(10):1459-1467
OBJECTIVE:
To observe the effect of acupuncture on chondrocyte autophagy in rats of knee osteoarthritis (KOA) and explore its underlying mechanisms.
METHODS:
Forty male SPF-grade SD rats were randomized into a blank group, a model group, a suspension group, an acupuncture group, and a combined therapy group, 8 rats in each one. Except the blank group, KOA model was prepared by the injection with papain. The suspension exercise therapy (10 min each time, three times daily), acupuncture (at "Yanglingquan" [GB34], "Zusanli" [ST36], and "Dubi" [ST35] on the right side, 30 min each intervention, once daily) and the combined therapy (the suspension exercise therapy combined with acupuncture) were delivered in the suspension group, the acupuncture group and the combined therapy group, respectively. The intervention of each group was performed continuously for 6 days, and 4 consecutive weeks, at the interval of 1 day. Before and after intervention, Lequesne MG score was assessed in the rats. After intervention, HE staining was adopted to observe the cartilaginous tissue morphology of the right knee joints, and Mankin score was evaluated; the serum levels of interleukin (IL)-1β, IL-6, and tumor neurosis factor-α (TNF-α) were measured using ELISA; the real-time PCR was provided to determine the mRNA expression of collagen protein type Ⅱ(COL2), collagen protein type Ⅹ (COL10), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR), and autophagy-regulated protein (Beclin-1) in the cartilaginous tissue of the right knee joint; Western blot was employed to detect the protein expression of PI3K, phosphorylated PI3K (p-PI3K), Akt, phosphorylated Akt (p-Akt), mTOR, phosphorylated mTOR (p-mTOR) and Beclin-1 in the cartilaginous tissue of the right knee joint.
RESULTS:
Compared with the blank group, the rats in the model group showed the higher Lequesne MG score (P<0.01), thinner cartilage of the right knee, reduced chondrocytes and disordered arrangement, and higher Mankin score (P<0.01). Besides, in the model group, the serum levels of IL-1β, IL-6 and TNF-α were elevated (P<0.01), the mRNA expression of COL2 and Beclin-1 and the protein expression of Beclin-1 decreased (P<0.01), the mRNA expression of COL10, PI3K, Akt and mTOR, and the protein expression of p-PI3K, p-Akt and p-mTOR increased (P<0.01) in the cartilaginous tissue of the right knee joint. Compared with the model group, in the suspension group, the acupuncture group and the combined therapy group, the Lequesne MG scores were reduced (P<0.01), the cartilage of the right knee was thickened, the arrangement of chondrocytes was improved, and the Mankin scores were lower (P<0.01). Besides, in these intervention groups, the serum levels of IL-1β, IL-6 and TNF-α were reduced (P<0.01), the mRNA expression of COL2 and Beclin-1 and the protein expression of Beclin-1 increased (P<0.05, P<0.01), the mRNA expression of COL10, PI3K, Akt and mTOR, and the protein expression of p-PI3K, p-Akt and p-mTOR decreased (P<0.05, P<0.01) in the cartilaginous tissue of the right knee joint. When compared with the suspension group and the acupuncture group, in the combined therapy group, the Lequesne MG score was reduced (P<0.01), and the Mankin score was reduced (P<0.05, P<0.01). Besides, the serum levels of IL-1β, IL-6 and TNF-α were reduced (P<0.05), the mRNA expression of COL2 and Beclin-1 and the protein expression of Beclin-1 increased (P<0.05), the mRNA expression of COL10, PI3K, Akt and mTOR, and the protein expression of p-PI3K, p-Akt and p-mTOR decreased (P<0.05, P<0.01) in the cartilaginous tissue of the right knee joint.
CONCLUSION
Acupuncture can promote cartilage regeneration of knee joint and autophagy in KOA rats, alleviate inflammation, so as to retard cartilage degeneration, which may be possibly associated with the PI3K/Akt/mTOR signaling pathway.
Animals
;
Male
;
Acupuncture Therapy
;
Proto-Oncogene Proteins c-akt/genetics*
;
TOR Serine-Threonine Kinases/genetics*
;
Osteoarthritis, Knee/physiopathology*
;
Phosphatidylinositol 3-Kinases/genetics*
;
Rats
;
Signal Transduction
;
Rats, Sprague-Dawley
;
Chondrocytes/metabolism*
;
Humans
;
Autophagy
;
Acupuncture Points
6.High expression of SURF4 promotes migration, invasion and proliferation of gastric cancer cells by inhibiting tight junction proteins.
Ziliang WANG ; Xiaohua CHEN ; Jingjing YANG ; Chen YAN ; Zhizhi ZHANG ; Bingyi HUANG ; Meng ZHAO ; Song LIU ; Sitang GE ; Lugen ZUO ; Deli CHEN
Journal of Southern Medical University 2025;45(8):1732-1742
OBJECTIVES:
To study the impact of SURF4 expression level on long-term prognosis of gastric cancer (GC) and biological behaviors of GC cells.
METHODS:
SURF4 expression level in GC and its association with long-term patient prognosis were analyzed using publicly available databases and in 155 GC patients with low and high SURF4 expressions detected immunohistochemically. The Cox proportional hazard model and Kaplan-Meier survival curves were used to analyze independent prognostic predictors of GC and the 5-year survival rate of the patients with different SURF4 expression levels. Informatics analyses were conducted to explore the correlation of SURF4 expression level with immune cell infiltration in GC, SURF4-related differential genes and their associated pathways. In cultured GC cell line HGC-27, the effects of SURF4 knockdown and overexpression on proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) were investigated.
RESULTS:
Analysis of GEPIA dataset and immunohistochemical results suggested significant SURF4 overexpression in GC (P<0.05), which was associated with shortened 5-year survival time of the patients (χ2=38.749, P<0.001). The prognosis of GC was closely related to tumor stage T3-4, N2-3, CEA≥5 μg/L and CA19-9≥37 kU/L (P<0.05). SURF4 expression level was negatively correlated with activated B cells, NK cells and CD8+ effector memory T cells (P<0.05) and positively correlated with CD4+ T cells (P<0.05). GO and KEGG enrichment analysis suggested that SUFR4 may participate in GC carcinogenesis by promoting EMT through the tight junction pathway. In HGC-27 cells, SURF4 overexpression significantly decreased E-cadherin expression, increased N-cadherin expression, inhibited ZO-1 and claudin-1 expressions, and promoted cell proliferation, migration and invasion.
CONCLUSIONS
SURF4 is highly expressed in GC, and its overexpression is associated with a shortened 5-year survival of the patients possibly by enhancing tumor cell proliferation, migration and invasion via inhibiting tight junction proteins and promoting EMT.
Humans
;
Stomach Neoplasms/metabolism*
;
Cell Proliferation
;
Cell Movement
;
Epithelial-Mesenchymal Transition
;
Cell Line, Tumor
;
Neoplasm Invasiveness
;
Prognosis
;
Tight Junction Proteins/metabolism*
;
Membrane Proteins/metabolism*
;
Female
;
Male
7.Role of Abelson interactor 2 in progression and prognosis of gastric cancer and its regulatory mechanisms
Xiaohua CHEN ; Hui LU ; Ziliang WANG ; Lian WANG ; Yongsheng XIA ; Zhijun GENG ; Xiaofeng ZHANG ; Xue SONG ; Yueyue WANG ; Jing LI ; Jianguo HU ; Lugen ZUO
Journal of Southern Medical University 2024;44(9):1653-1661
Objective To explore the regulatory role of Abelson interactor 2(ABI2)in progression and prognosis of gastric cancer.Methods TIMER2.0,GEPIA,Kaplan-Meier Plotter and DAVID databases were used to analyze ABI2 expression in pan-cancer and its association with the prognosis of gastric cancer.Gastric cancer and adjacent tissues from 120 patients undergoing radical gastrectomy in our hospital between January,2016 and October,2018 were examined for ABI2 expression and its correlation with disease progression and prognosis.MGC-803 cell models of ABI2 knockdown and overexpression were established for observing the changes in cell proliferation,migration,and invasion,and the impact of ABI2 expression modulation on xenograft growth was evaluated in nude mice.Results Database analysis and examination of the clinical samples showed that ABI2 was highly expressed in gastric cancer tissues.Survival analysis suggested that gastric cancer patients with a high expression of ABI2 had a reduced postoperative 5-year survival rate(P<0.0001),and further Cox univariate and multivariate survival analyses indicated that a high ABI2 expression was an independent risk factor affecting the patients survival outcomes(P=0.022,HR=1.887,95%CI:1.096-3.249).Enrichment analysis suggested the involvement of ABI2 in Wnt signaling.In MGC-803 cells,ABI2 overexpression promoted cell proliferation and xenograft growth in nude mice,increased the expressions of vimentin and N-cadherin,and lowered E-cadherin expression,while ABI2 knockdown produced the opposite effects.Mechanistic analysis revealed that ABI2 overexpression promoted the expressions of Wnt2 and β-catenin in both MGC-803 cells and the xenografts,and their expressions were significantly lowered by ABI2 knockdown.Conclusion ABI2 is highly expressed in gastric cancer,which affects long-term prognosis of the patients,possible due to its regulatory effect on Wnt signaling to promote proliferation,migration and invasion of gastric cancer cells.
8.CEP192 overexpression is correlated with poor prognosis of gastric cancer and promotes gastric cancer cell proliferation by regulating PLK1/CDK1/Cyclin B1 signaling
Zhen ZHANG ; Hui LU ; Xiaohua CHEN ; Lian WANG ; Ziliang WANG ; Yueyue WANG ; Sitang GE ; Lugen ZUO
Journal of Southern Medical University 2024;44(11):2137-2145
Objective To investigate the correlation of CEP192 expression with prognosis of gastric cancer and biological behaviors of gastric cancer cells.Methods Public databases and clinical tissue samples were used to examine CEP192 expression level in gastric cancer.Kaplan-Meier survival curves,univariate and multivariate Cox regression analyses,ROC curves and bioinformatics analyses were used to explore the risk factors affecting the 5-year postoperative survival,the correlation of CEP192 expression level with the patients'survival,and its biological role in gastric cancer development.In gastric cancer MGC-803 cells with lentivirus-mediated CEP192 interference or overexpression,cell proliferation and expressions of PLK1,CDK1 and Cyclin B1 were examined with CCK-8 assay and Western blotting.The effects of CEP192 knockdown or overexpression on tumorigenesis of MGC-803 cells was observed in nude mice,and the expressions of PLK1,CDK1 and Cyclin B1 in the xenografts were detected.Results CEP192 was highly expressed in gastric cancer and associated with poor prognosis of the patients(P<0.05).High expression of CEP192,CEA≥5 ng/mL,CA199≥37 IU/mL,T3-4 stage,and N2-3 stage were independent risk factors affecting the patients'5-year postoperative survival(P<0.05).Bioinformatics analyses suggested that CEP192 was involved in several vital biological processes and positively regulated cell cycle progression.In MGC-803 cells,CEP192 knockdown significantly inhibited cell proliferation and lowered the expression levels of PLK1,CDK1,and Cyclin B1,while its overexpression produced the opposite effects.In the nude mouse models,CEP192 knockdown resulted in lowered tumorigenic potential of MGC-803 cells and decreased protein levels of PLK1,CDK1,and Cyclin B1 in the xenografts,while CEP192 overexpression in MGC-803 cells caused the opposite changes.Conclusion CEP192 overexpression is correlated with unfavorable outcomes of gastric cancer patients and promotes gastric cell proliferation by regulating the key proteins during G2/M phase transition.
9.Research progress on food-derived antioxidants for alleviating toxicity of endocrine disrupting chemicals
Jiaxian CHEN ; Maohua MIAO ; Ziliang WANG
Journal of Environmental and Occupational Medicine 2024;41(1):110-117
Endocrine disrupting chemicals (EDCs) are a class of chemical substances widely present in daily-life environment, and can enter human body through various pathways, posing a threat to reproductive development and health. Oxidative stress (OS) is one of the most important fundamental mechanisms underlying the reproductive toxicity of EDCs. Numerous studies have found that exposure to EDCs can increase the levels of reactive oxygen species (ROS) in human reproductive system and reduce the activity and quantity of multiple enzymatic antioxidants, leading to oxidative stress and inducing damage to the reproductive system at various levels such as DNA and cells. Many research results have shown that supplementing food-derived non-enzymatic antioxidants can reduce ROS levels and increase the activity of enzymatic antioxidants, thereby reduce OS levels, and further repair EDCs-induced reproductive damage. In addition, many food-derived antioxidants are important elements involved in reproductive physiological activities and have protective effects on reproductive health. This paper summarized the reproductive toxicity of EDCs, including damage to reproductive cells, interference with hormone action, and influence on reproductive-related epigenetic regulation, elaborated the relationship between OS and reproductive toxicity of EDCs, and further summarized the alleviating effects and related mechanisms of food-derived antioxidants such as vitamins, trace elements, and plant polyphenols and pigments against reproductive toxicity of EDCs, aiming to provide a theoretical and scientific basis for prevention and treatment against reproductive toxicity of EDCs.
10.Multilevel Pedicle Subtraction Osteotomy for Correction of Thoracolumbar Kyphosis in Ankylosing Spondylitis: Clinical Effect and Biomechanical Evaluation
Xin LV ; Yelidana NUERTAI ; Qiwei WANG ; Di ZHANG ; Xumin HU ; Jiabao LIU ; Ziliang ZENG ; Renyuan HUANG ; Zhihao HUANG ; Qiancheng ZHAO ; Wenpeng LI ; Zhilei ZHANG ; Liangbin GAO
Neurospine 2024;21(1):231-243
Objective:
To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters.
Methods:
Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions.
Results:
Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO.
Conclusion
Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

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