1.Time-Dependent Transcriptional Dynamics of Contextual Fear Memory Retrieval Reveals the Function of Dipeptidyl Peptidase 9 in Reconsolidation.
Wen-Ting GUO ; Wen-Xing LI ; Yu-Chen LIU ; Ya-Bo ZHAO ; Lin XU ; Qi-Xin ZHOU
Neuroscience Bulletin 2025;41(1):16-32
Numerous studies on the formation and consolidation of memory have shown that memory processes are characterized by phase-dependent and dynamic regulation. Memory retrieval, as the only representation of memory content and an active form of memory processing that induces memory reconsolidation, has attracted increasing attention in recent years. Although the molecular mechanisms specific to memory retrieval-induced reconsolidation have been gradually revealed, an understanding of the time-dependent regulatory mechanisms of this process is still lacking. In this study, we applied a transcriptome analysis of memory retrieval at different time points in the recent memory stage. Differential expression analysis and Short Time-series Expression Miner (STEM) depicting temporal gene expression patterns indicated that most differential gene expression occurred at 48 h, and the STEM cluster showing the greatest transcriptional upregulation at 48 h demonstrated the most significant difference. We then screened the differentially-expressed genes associated with that met the expression patterns of those cluster-identified genes that have been reported to be involved in learning and memory processes in addition to dipeptidyl peptidase 9 (DPP9). Further quantitative polymerase chain reaction verification and pharmacological intervention suggested that DPP9 is involved in 48-h fear memory retrieval and viral vector-mediated overexpression of DPP9 countered the 48-h retrieval-induced attenuation of fear memory. Taken together, our findings suggest that temporal gene expression patterns are induced by recent memory retrieval and provide hitherto undocumented evidence of the role of DPP9 in the retrieval-induced reconsolidation of fear memory.
Animals
;
Fear/physiology*
;
Male
;
Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/genetics*
;
Memory Consolidation/physiology*
;
Time Factors
;
Mental Recall/drug effects*
;
Mice
;
Gene Expression Profiling
2.Non-invasive Modulation of Deep Brain Nuclei by Temporal Interference Stimulation.
Long LI ; Hao BAI ; Linyan WU ; Liang ZHENG ; Liang HUANG ; Yang LI ; Wenlong ZHANG ; Jue WANG ; Shunnan GE ; Yan QU ; Tian LIU
Neuroscience Bulletin 2025;41(5):853-865
Temporal interference (TI) is a form of stimulation that epitomizes an innovative and non-invasive approach for profound neuromodulation of the brain, a technique that has been validated in mice. Yet, the thin cranial bone structure of mice has a marginal influence on the effect of the TI technique and may not effectively showcase its effectiveness in larger animals. Based on this, we carried out TI stimulation experiments on rats. Following the TI intervention, analysis of electrophysiological data and immunofluorescence staining indicated the generation of a stimulation focus within the nucleus accumbens (depth, 8.5 mm) in rats. Our findings affirm the viability of the TI methodology in the presence of thick cranial bones, furnishing efficacious parameters for profound stimulation with TI administered under such conditions. This experiment not only sheds light on the intervention effects of TI deep in the brain but also furnishes robust evidence in support of its prospective clinical utility.
Animals
;
Deep Brain Stimulation/methods*
;
Nucleus Accumbens/physiology*
;
Male
;
Rats
;
Rats, Sprague-Dawley
;
Time Factors
3.Construction of a risk prediction model for the timing of weaning extracorporeal membrane oxygenation.
Dehua ZENG ; Xifeng LIU ; Zhibiao HE ; Aiqun ZHU
Chinese Critical Care Medicine 2025;37(9):866-870
OBJECTIVE:
To explore the timing of weaning extracorporeal membrane oxygenation (ECMO) and analyze the risk factors that affect survival outcomes before weaning.
METHODS:
A retrospective case-control study was conducted. Patients who received ECMO treatment and were weaned according to physicians' orders at the Second Xiangya Hospital of Central South University from January 2020 to June 2024 were enrolled as the study subjects. The general information, underlying diseases, indications and processes of ECMO, vital signs and arterial blood gas analysis 1 hour before weaning test, and biochemical indicators 24 hours before weaning test were collected through the hospital electronic medical record system. The primary outcome measure was the hospital mortality. The variables with P < 0.1 in univariate analysis and correlation analysis were included into binary Logistic regression analysis to identify risk factors. A nomogram model was constructed to predict the risk of weaning death in patients with ECMO, and receiver operator characteristic curve (ROC curve) and calibration curve were drawn to evaluate the model. Decision curve analysis (DCA) was used to evaluate the clinical net benefit rate of the model.
RESULTS:
A total of 32 ECMO patients were included, among whom 10 received veno-arterial ECMO (VA-ECMO) and 22 received veno-venous ECMO (VV-ECMO). During the hospitalization period, 23 patients survived, while 9 died. The time from mechanical ventilation to ECMO activation in the death group was significantly longer than that in the survival group, and the time from ECMO cessation to discharge was significantly shorter than that in the survival group. The levels of diastolic blood pressure (DBP) and albumin (Alb) before weaning were significantly lower than those in the survival group, and the level of procalcitonin (PCT) was significantly higher than that in the survival group (all P < 0.05). Spearman correlation analysis showed that DBP, PCT, Alb, and thrombin time (TT) were correlated with the weaning outcomes of ECMO patients (r values were -0.450, 0.373, -0.376, -0.346, all P < 0.1). Binary Logistic regression analysis showed that the final indicators entering the regression equation included DBP [odds ratio (OR) = 0.864, 95% confidence interval (95%CI) was 0.756-0.982], PCT (OR = 1.157, 95%CI was 0.679-1.973), and TT (OR = 0.852, 95%CI was 0.693-1.049), and a nomogram model was constructed to predict the weaning outcomes of ECMO patients. ROC curve analysis showed that the area under the curve (AUC) of the nomogram model for predicting the weaning outcome of ECMO patients was 0.831, with a sensitivity of 77.8% and a specificity of 65.2%. Its predictive value was better than that of single indicators DBP, PCT, and TT (AUC of 0.787, 0.739, and 0.722, respectively). The calibration curve showed that the prediction probability of the model was in good consistency with the actual observed results, the Hosmer-Lemeshow goodness of fit test showed that, χ 2 = 8.3521, P = 0.400, indicating that the model fits well. DCA showed that across risk threshold of 0-0.8, the net benefit rate was greater than 0, which was significantly better than that of single indicator.
CONCLUSIONS
The nomogram model constructed with DBP, PCT, and TT has certain predictive value for the weaning outcomes of ECMO patients and can be used as a screening indicator for ECMO weaning timing.
Humans
;
Extracorporeal Membrane Oxygenation
;
Retrospective Studies
;
Risk Factors
;
Case-Control Studies
;
Hospital Mortality
;
Male
;
Female
;
Nomograms
;
Logistic Models
;
ROC Curve
;
Middle Aged
;
Adult
;
Ventilator Weaning
;
Time Factors
4.Research progress on the timing of initiation of renal replacement therapy in patients with sepsis-associated acute kidney injury.
Yating YAN ; He GUO ; Ruimin TAN ; Quansheng DU
Chinese Critical Care Medicine 2025;37(9):889-892
Acute kidney injury (AKI) is one of the most common complications in critically ill patients, and sepsis is the main cause of AKI in the intensive care unit (ICU), which can lead to a poor prognosis in severe cases. For patients with sepsis-associated acute kidney injury (SA-AKI) for whom urgent dialysis is indicated, it is now clear that renal replacement therapy (RRT) can be initiated immediately to control disease progression. However, the optimal timing to initiate RRT in patients whose disease is not severe enough to warrant urgent dialysis remains controversial. Some previous studies were small and heterogeneous, and there was a lack of effective reference indicators for guiding RRT in SA-AKI patients. Therefore, this article reviews the relevant experimental studies on the treatment of critically ill patients with AKI in recent years, and reviews the latest research progress on the optimal timing of RRT initiation, in order to provide an effective reference for clinical practice.
Humans
;
Acute Kidney Injury/etiology*
;
Renal Replacement Therapy/methods*
;
Sepsis/therapy*
;
Time Factors
;
Intensive Care Units
5.Construction of a risk prediction model for the timing of extracorporeal membrane oxygenation initiation.
Dehua ZENG ; Xifeng LIU ; Zhibiao HE ; Aiqun ZHU
Chinese Critical Care Medicine 2025;37(8):762-767
OBJECTIVE:
To identify the risk factors related to the timing of patients receiving extracorporeal membrane oxygenation (ECMO) initiation and construct a risk prediction model for ECMO initiation timing.
METHODS:
Patients who received ECMO admitted to the Second Xiangya Hospital of Central South University from January 2020 to January 2024 were retrospectively collected. The case data mainly included physiological and biochemical indicators 1 hour before ECMO initiation. According to the outcome of the patients, they were divided into survival group and death group. Univariate and multivariate Logistic regression analysis were used to analyze the predictors of mortality risk in patients with ECMO, and a nomogram prediction model was constructed. The discrimination, calibration accuracy, and goodness of the model were evaluated by the receiver operator characteristic curve (ROC curve), calibration curve, and the Hosmer-Lemeshow test, respectively. Decision curve analysis (DCA) evaluated the clinical net benefit rate of the model.
RESULTS:
A total of 81 ECMO patients were included, including 59 males and 22 females; age range from 16 to 61 years old, with a median age of 56.0 (39.5, 61.5) years old; 20 patients received veno-arterial (V-A) ECMO, and 61 patients received veno-venous (V-V) ECMO; 23 patients ultimately survived and 58 patients died. Univariate analysis showed that age, blood urea nitrogen, serum creatinine, D-dimer, arterial blood carbon dioxide partial pressure, and prothrombin time of the death group were all higher than those of the survival group, while albumin was slightly lower than that of the survival group. There was a statistically significant difference in the direct cause of ECMO initiation between the two groups. Multivariate Logistic regression analysis showed that age [odds ratio (OR) = 1.069, 95% confidence interval (95%CI) was 1.015-1.125, P = 0.012], direct cause of ECMO initiation [with heart failure as the reference, return of spontaneous circulation (ROSC) after cardiopulmonary support (OR = 30.672, 95%CI was 1.265-743.638, P = 0.035), novel coronavirus infection (OR = 8.666, 95%CI was 0.818-91.761, P = 0.073), other severe pneumonia (OR = 4.997, 95%CI was 0.558-44.765, P = 0.150)], pre-ECMO serum creatinine (OR = 1.008, 95%CI was 1.000-1.016, P = 0.044), prothrombin time (OR = 1.078, 95%CI was 0.948-1.226, P = 0.252), and D-dimer (OR = 1.135, 95%CI was 1.047-1.231, P = 0.002) were entered into the final regression equation. A nomogram prediction model was developed based on these five factors. The area under the ROC curve (AUC) of the model was 0.889 (95%CI was 0.819-0.959), higher than the AUC of the sequential organ failure assessment (SOFA; AUC = 0.604, 95%CI was 0.467-0.742). The calibration curve showed good consistency between the model predictions and the observed results. The Hosmer-Lemeshow goodness-of-fit test showed that χ 2 = 4.668, P = 0.792. DCA analysis showed that when the risk threshold was 0-0.8, the net benefit rate was greater than 0, which was significantly better than that of SOFA score.
CONCLUSIONS
The risk prediction model for the timing of ECMO initiation, constructed using five factors (age, direct cause of ECMO initiation, thrombin time, serum creatinine, and D-dimer), demonstrated good discrimination and calibration. It can serve as a pre-initiation assessment tool to identify and predict post-initiation mortality risk in ECMO patients.
Humans
;
Extracorporeal Membrane Oxygenation
;
Middle Aged
;
Male
;
Female
;
Retrospective Studies
;
Adult
;
Risk Factors
;
Adolescent
;
Young Adult
;
Logistic Models
;
Nomograms
;
ROC Curve
;
Time Factors
;
Risk Assessment
6.Application of delayed replantation of degloving skin preserved at 4 ℃ in treatment of limb degloving injuries.
Qianqian XU ; Jihai XU ; Yijun SHEN ; Chenxi ZHANG ; Hangchong SHEN ; Tianxiang HUANG ; Chenlin LU ; Xin WANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(1):95-99
OBJECTIVE:
To investigate the effectiveness of delayed replantation of degloving skin preserved at 4℃ in treatment of limb degloving injuries.
METHODS:
Between October 2020 and October 2023, 12 patients with limb degloving injuries were admitted. All patients had severe associated injuries or poor wound conditions that prevented primary replantation. There were 7 males and 5 females; age ranged from 29 to 46 years, with an average of 39.2 years. The causes of injury included machine entanglement in 6 cases, traffic accidents in 5 cases, and sharp instrument cuts in 1 case. Time from injury to hospital admission was 0.5-3.0 hours, with an average of 1.3 hours. Injury sites included upper limbs in 7 cases and lower limbs in 5 cases. The range of degloving skin was from 5 cm×4 cm to 15 cm×8 cm, and all degloving skins were intact. The degloving skin was preserved at 4℃. After the patient's vital signs became stable and the wound conditions improved, it was trimmed into medium-thickness skin grafts for replantation. The degloving skin was preserved for 3 to 7 days. At 4 weeks after replantation, the viability of the degloving skin grafts was assessed, including color, elasticity, and sensation of pain. The Vancouver Scar Scale (VSS) was used to assess the scars of the skin grafts during follow-up.
RESULTS:
At 4 weeks after replantation, 8 cases of skin grafts completely survived and the color was similar with normal skin, with a survival rate of 66.67%. The elasticity of skin grafts (R0 value) ranged from 0.09 to 0.85, with an average of 0.55; moderate pain was reported in 4 cases, mild pain in 3 cases, and no pain in 5 cases. All patients were followed up 12 months. Over time, the VSS scores of all 12 patients gradually decreased, with a range of 4-11 at 12 months (mean, 6.8).
CONCLUSION
For limb degloving injuries that cannot be replanted immediately and do not have the conditions for deep low-temperature freezing preservation, the method of preserving the degloving skin at 4℃ for delayed replantation can be chosen.
Humans
;
Male
;
Adult
;
Replantation/methods*
;
Female
;
Degloving Injuries/surgery*
;
Middle Aged
;
Skin Transplantation/methods*
;
Treatment Outcome
;
Extremities/injuries*
;
Time Factors
;
Skin/injuries*
;
Tissue Preservation/methods*
7.Impact of surgical timing on effectiveness of closed reduction and percutaneous Kirschner wire fixation for pediatric supracondylar humerus fractures.
Tianlong PAN ; Xianghua HOU ; Jingdong ZHANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(5):569-573
OBJECTIVE:
To compare the effectiveness of early versus delayed closed reduction and percutaneous Kirschner wire fixation in the treatment of pediatric supracondylar humerus fractures.
METHODS:
A retrospective analysis was conducted on 468 children with supracondylar humerus fractures, who were admitted between January 2020 and December 2023 and met the inclusion criteria. Among them, 187 children were treated during 12 hours after injury (early operation group) and 281 were treated after 12 hours (delayed operation group). There was no significant difference between the two groups ( P>0.05) in the gender, age, injury mechanism, fracture side and type, while there was significant difference in interval from injury to operation ( P<0.05). The operative outcomes, including the operation time, intraoperative blood loss, the length of hospital stay, fracture healing time, elbow function assessed by Flynn criteria at 3 months after operation, and complications, were compared.
RESULTS:
Compared to the delayed operation group, the early operation group demonstrated significantly shorter operation time and less intraoperative blood loss ( P<0.05). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). All children were followed up 3-12 months. The follow-up time was (6.7±2.9) months in the early operation group and (6.9±2.8) months in the delayed operation group, showing no significant difference between the two groups ( P>0.05). There was no significant difference in the fracture healing time between the two groups ( P>0.05). At 3 months after operation, the early operation group exhibited superior Flynn elbow functional outcomes to the delayed operation group ( P<0.05). In the early operation group, there was 1 case of fracture non-union and 3 cases of cubital varus deformity after operation. In the delayed operation group, there was 1 case of nerve injury, 7 cases of fracture non-union, and 12 cases of cubital varus deformity after operation. There was significant difference in the incidence of complications between the two groups ( P<0.05). One case of the early operation group and 10 cases of the delayed operation group underwent secondary operation, showing no significant difference in the incidence of secondary operation between the two groups ( P>0.05).
CONCLUSION
For pediatric supracondylar humerus fractures, early closed reduction and percutaneous Kirschner wire fixation can reduce operation time, minimize intraoperative blood loss and postoperative complications, and improve the functional recovery compared to delayed operation.
Humans
;
Humeral Fractures/surgery*
;
Bone Wires
;
Retrospective Studies
;
Male
;
Female
;
Child
;
Fracture Fixation, Internal/instrumentation*
;
Child, Preschool
;
Treatment Outcome
;
Operative Time
;
Fracture Healing
;
Length of Stay
;
Closed Fracture Reduction/methods*
;
Blood Loss, Surgical
;
Time Factors
;
Time-to-Treatment
;
Postoperative Complications/epidemiology*
8.Poster Fusion Cage combined with xenogeneic bone graft augmentation for bone defect management in distal radius fractures.
Yi GAO ; Xiaomeng REN ; Chuyang ZENG ; Longbo DU ; Meng LI ; Rui MA ; Wei ZHANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(6):655-661
OBJECTIVE:
To evaluate the effectiveness of Poster Fusion Cage combined with xenogeneic bone graft augmentation for bone defect management in distal radius fractures.
METHODS:
A retrospective analysis was conducted on 20 patients with bone defects complicating distal radius fractures who met the selection criteria and were treated between June 2022 and June 2024. The cohort comprised 2 males and 18 females, aged 54-87 years (mean, 63.3 years). Etiologies included falls in 17 cases, traffic accidents in 2 cases, and crush injury in 1 case. According to AO classification, there were 5 cases of type A, 8 cases of type B, and 7 cases of type C. The interval from injury to operation ranged from 2 to 10 days (mean, 5.8 days). All patients underwent volar plate fixation augmented with Poster Fusion Cage and demineralized xenogeneic bone matrix grafting. The operation time, intraoperative blood loss, fracture healing time, and postoperative complications were recorded. Radiographic parameters, including radial height, volar tilt, and ulnar deviation, were measured on standardized X-ray films obtained immediately postoperatively and at last follow-up, and whether secondary reduction loss occurred was judged. At last follow-up, wrist range of motion (extension, flexion, radial deviation, ulnar deviation, pronation, and supination) and grip strength (expressed as a percentage of the contralateral side) were measured. Wrist function was assessed using the Disabilities of the Arm, Shoulder, and Hand (DASH) score and Patient-Rated Wrist Evaluation (PRWE) score.
RESULTS:
The operation time was 70-200 minutes (mean, 116.4 minutes), and the intraoperative blood loss was 10-80 mL (mean, 36.5 mL). All surgical incisions healed by first intention, with no neurovascular complications documented. All patients were followed up 9-12 months (mean, 11.6 months). All fractures healed normally, with a healing time of 8-14 weeks (mean, 9.95 weeks). No significant difference was observed in radial height, volar tilt, or ulnar deviation between immediate postoperatively and last follow-up ( P>0.05). All fractures achieved satisfactory reduction, with no secondary loss of reduction or implant failure occurring during follow-up. At last follow-up, the range of motion of the affected wrist joint was 60°-65° (mean, 62.5°) in extension, 67°-75° (mean, 71.1°) in flexion, 18°-23° (mean, 20.4°) in radial deviation, 28°-33° (mean, 30.1°) in ulnar deviation, 69°-80° (mean, 74.7°) in pronation, and 69°-82° (mean, 75.6°) in supination. Grip strength recovered to 75%-85% (mean, 80%) of the contralateral side. Functional scores showed a DASH score of 5-15 (mean, 9.4) and PRWE score of 8.0-12.5 (mean, 10.2).
CONCLUSION
The combination of Poster Fusion Cage and xenogeneic bone graft augmentation provides a safe and effective treatment for bone defects in distal radius fractures.
Retrospective Studies
;
Humans
;
Male
;
Female
;
Middle Aged
;
Aged
;
Aged, 80 and over
;
Treatment Outcome
;
Wrist Fractures/surgery*
;
Heterografts
;
Transplantation, Heterologous/methods*
;
Bone Transplantation/methods*
;
Operative Time
;
Blood Loss, Surgical
;
Radius/surgery*
;
Fracture Healing
;
Time Factors
;
Postoperative Complications/etiology*
;
Range of Motion, Articular
;
Follow-Up Studies
;
Internal Fixators
;
Fracture Fixation, Internal/methods*
;
Combined Modality Therapy
9.Glycemic Control and Diabetes Duration in Relation to Subsequent Myocardial Infarction among Patients with Coronary Heart Disease and Type 2 Diabetes.
Fu Rong LI ; Yan DOU ; Chun Bao MO ; Shuang WANG ; Jing ZHENG ; Dong Feng GU ; Feng Chao LIANG
Biomedical and Environmental Sciences 2025;38(1):27-36
OBJECTIVE:
This study aimed to investigate the impact of glycemic control and diabetes duration on subsequent myocardial infarction (MI) in patients with both coronary heart disease (CHD) and type 2 diabetes (T2D).
METHODS:
We conducted a retrospective cohort study of 33,238 patients with both CHD and T2D in Shenzhen, China. Patients were categorized into 6 groups based on baseline fasting plasma glucose (FPG) levels and diabetes duration (from the date of diabetes diagnosis to the baseline date) to examine their combined effects on subsequent MI. Cox proportional hazards regression models were used, with further stratification by age, sex, and comorbidities to assess potential interactions.
RESULTS:
Over a median follow-up of 2.4 years, 2,110 patients experienced MI. Compared to those with optimal glycemic control (FPG < 6.1 mmol/L) and shorter diabetes duration (< 10 years), the fully-adjusted hazard ratio ( HR) (95% Confidence Interval [95% CI]) for those with a diabetes duration of ≥ 10 years and FPG > 8.0 mmol/L was 1.93 (95% CI: 1.59, 2.36). The combined effects of FPG and diabetes duration on MI were largely similar across different age, sex, and comorbidity groups, although the excess risk of MI associated with long-term diabetes appeared to be more pronounced among those with atrial fibrillation.
CONCLUSION
Our study indicates that glycemic control and diabetes duration significant influence the subsequent occurrence of MI in patients with both CHD and T2D. Tailored management strategies emphasizing strict glycemic control may be particularly beneficial for patients with longer diabetes duration and atrial fibrillation.
Humans
;
Diabetes Mellitus, Type 2/blood*
;
Male
;
Female
;
Middle Aged
;
Aged
;
Coronary Disease/complications*
;
Myocardial Infarction/etiology*
;
Retrospective Studies
;
China/epidemiology*
;
Glycemic Control
;
Blood Glucose
;
Adult
;
Risk Factors
;
Time Factors
10.A cross-sectional study on improving clinical efficiency through centralized digital impression.
West China Journal of Stomatology 2025;43(1):63-67
OBJECTIVES:
This study aims to explore the effect of improving clinical efficiency by replacing traditional impression workflow with centralized digital impression workflow.
METHODS:
The department of prosthodontics in Center of Stomatology, Peking University Shenzhen Hospital has improved the clinical workflow by replacing the traditional impression made by doctors using impression materials for each patient with a centralized digital impression made by one technician for all patients in the department. This cross-sectional study recorded the chairside time required for impression taking in patients undergoing single posterior zirconia full crown restoration before clinical process improvement; the time required for centralized digital impression production; the comfort level of patients; and the adjacency relationship, occlusal contact relationship, and time required for prostheses adjusting (i.e., whether centralized digital impressions would compromise the quality of pro-stheses and increase the time of prostheses adjusting).
RESULTS:
The average time to make a traditional impression was (9.98±1.41) min, and the average time required for each patient to make a centralized digital impression was (5.98±1.49) min, which was shorter than that to used make a traditional impression (P<0.05). Centralized digital impression made patients feel more comfortable compared with traditional impression (P<0.05). The adjacency relationship of restorations by centralized digital impression was more appropriate (P<0.05), and no significant difference in occlusal relationship was found (P>0.05). The time required for adjusting prostheses also had no significant differences (P>0.05).
CONCLUSIONS
Centralized digital impression can improve clinical efficiency for patients undergoing single posterior zirconia crown restoration. The time for impression taking is shorter, and patients feel more comfortable without compromising the quality of the prostheses.
Humans
;
Cross-Sectional Studies
;
Dental Impression Technique
;
Crowns
;
Zirconium
;
Workflow
;
Computer-Aided Design
;
Time Factors
;
Dental Impression Materials

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