1.Effects of VX765 on osteoarthritis and chondrocyte inflammation in rats.
Wanran HUANG ; Junxue TU ; Aiqing QIAO ; Chujun HE
Chinese Journal of Reparative and Reconstructive Surgery 2024;38(1):74-81
OBJECTIVE:
To investigate the effects and underlying mechanisms of VX765 on osteoarthritis (OA) and chondrocytes inflammation in rats.
METHODS:
Chondrocytes were isolated from the knee joints of 4-week-old Sprague Dawley (SD) rats. The third-generation cells were subjected to cell counting kit 8 (CCK-8) analysis to assess the impact of various concentrations (0, 1, 5, 10, 20, 50, 100 μmol/L) of VX765 on rat chondrocyte activity. An <i>in vitroi> lipopolysaccharide (LPS) induced cell inflammation model was employed, dividing cells into control group, LPS group, VX765 concentration 1 group and VX765 concentration 2 group without obvious cytotoxicity. Western blot, real-time fluorescence quantitative PCR, and ELISA were conducted to measure the expression levels of inflammatory factors-transforming growth factor β 1 (TGF-β 1), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Additionally, Western blot and immunofluorescence staining were employed to assess the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1). Thirty-two SD rats were randomly assigned to sham surgery group (group A), OA group (group B), OA+VX765 (50 mg/kg) group (group C), and OA+VX765 (100 mg/kg) group (group D), with 8 rats in each group. Group A underwent a sham operation with a medial incision, while groups B to D underwent additional transverse incisions to the medial collateral ligament and anterior cruciate ligament, with removal of the medial meniscus. One week post-surgery, groups C and D were orally administered 50 mg/kg and 100 mg/kg VX765, respectively, while groups A and B received an equivalent volume of saline. Histopathological examination using HE and safranin-fast green staining was performed, and Mankin scoring was utilized for evaluation. Immunohistochemical staining technique was employed to analyze the expressions of matrix metalloproteinase 13 (MMP-13) and collagen type Ⅱ.
RESULTS:
The CCK-8 assay indicated a significant decrease in cell viability at VX765 concentrations exceeding 10 μmol/L ( <i>Pi><0.05), so 4 μmol/L and 8 μmol/L VX765 without obvious cytotoxicity were selected for subsequent experiments. Following LPS induction, the expressions of TGF-β 1, IL-6, and TNF-α in cells significantly increased when compared with the control group ( <i>Pi><0.05). However, intervention with 4 μmol/L and 8 μmol/L VX765 led to a significant decrease in expression compared to the LPS group ( <i>Pi><0.05). Western blot and immunofluorescence staining demonstrated a significant upregulation of Nrf2 pathway-related molecules Nrf2 and HO-1 protein expressions by VX765 ( <i>Pi><0.05), indicating Nrf2 pathway activation. Histopathological examination of rat knee joint tissues and immunohistochemical staining revealed that, compared to group B, treatment with VX765 in groups C and D improved joint structural damage in rat OA, alleviated inflammatory reactions, downregulated MMP-13 expression, and increased collagen type Ⅱ expression.
CONCLUSION
VX765 can improve rat OA and reduce chondrocyte inflammation, possibly through the activation of the Nrf2 pathway.
Rats
;
Animals
;
Chondrocytes/metabolism*
;
Matrix Metalloproteinase 13/metabolism*
;
Rats, Sprague-Dawley
;
Tumor Necrosis Factor-alpha/metabolism*
;
Collagen Type II/metabolism*
;
Interleukin-6
;
Lipopolysaccharides/pharmacology*
;
NF-E2-Related Factor 2/pharmacology*
;
Inflammation/drug therapy*
;
Osteoarthritis/metabolism*
;
Transforming Growth Factor beta1/metabolism*
;
Dipeptides
;
para-Aminobenzoates
2.Study on injectable chitosan hydrogel with tendon-derived stem cells for enhancing rotator cuff tendon-to-bone healing.
Huawei WEN ; Qingsong ZHANG ; Ming TANG ; Ya'nan LI ; Hongfei TAN ; Yushun FANG
Chinese Journal of Reparative and Reconstructive Surgery 2024;38(1):91-98
OBJECTIVE:
To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits.
METHODS:
TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture <i>in vitroi>, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( <i>ni>=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties.
RESULTS:
CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( <i>Pi><0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( <i>Pi><0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( <i>Pi><0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( <i>Pi><0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( <i>Pi><0.05), while there was no significant difference in the number of cells and vascularity ( <i>Pi>>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( <i>Pi><0.05), but there was no significant difference compared to the CS group ( <i>Pi>>0.05).
CONCLUSION
TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.
Rabbits
;
Animals
;
Rotator Cuff/surgery*
;
Chitosan
;
Hydrogels
;
Rotator Cuff Injuries/surgery*
;
Wound Healing
;
Tendons/surgery*
;
Collagen
;
Stem Cells
;
Biomechanical Phenomena
3.Case report: Spontaneous resolution of acquired perforating collagenosis following insect bite
Natasha G. Manzo ; Maria Patricia A. Chavez
Journal of the Philippine Dermatological Society 2024;33(Suppl 1):1-2
Acquired perforating collagenosis (APC) is a rare dermatological condition characterized by the spontaneous eruption of skin-colored or erythematous papules or nodules that eventually ulcerate and exude collagenous material. The exact etiology of APC remains unclear, although various triggers, including infections, medications, autoimmune diseases, and trauma, have been implicated.
This case report presents a 63-year-old female with a history of diabetes who developed erythematous papules and plaques topped with thick, yellowish, hyperkeratotic, adherent crusts on the upper back following an insect bite. Histopathological examination confirmed the diagnosis of APC, characterized by a cup-shaped invagination in the epidermis containing degenerated collagen bundles and basophilic material. Masson-trichrome staining showed transepidermal elimination of the collagen fibers. Patient was initially prescribed tretinoin 0.1% cream to be applied 2x a day. However, patient was not able to apply prescribed medications. Interestingly, without any specific treatment, the patient’s symptoms gradually improved over 3 months and eventually resolved completely.
This case report highlights the spontaneous resolution of APC in a patient following an insect bite. While most cases of APC require medical intervention, this case demonstrates the potential for spontaneous healing in certain individuals. Further research is needed to understand the factors that influence the course of APC and to identify potential predictors of spontaneous resolution.
Human ; Female ; Middle Aged: 45-64 Yrs Old ; Collagen ; Insect Bites ; Insect Bites And Stings
5.Panax notoginseng saponins improve monocrotaline-induced pulmonary arterial hypertension in rats by inhibiting ADAM10/Notch3 signaling pathway.
Sai ZHANG ; Yun-Na TIAN ; Zheng-Yang SONG ; Xiao-Ting WANG ; Xin-Yu WANG ; Jun-Peng XU ; Lin-Bo YUAN ; Wan-Tie WANG
Acta Physiologica Sinica 2023;75(4):503-511
In this study, we investigated the effects of Panax notoginseng saponins (PNS) on pulmonary vascular remodeling and ADAM10/Notch3 pathway in pulmonary arterial hypertension (PAH). PAH rat model was established, and male Sprague Dawley (SD) rats were randomly divided into control group, monocrotaline (MCT) group and MCT+PNS group, with 10 rats in each group. Rats in the control group were intraperitoneally injected with equal volume of normal saline. Rats in the MCT group was injected intraperitoneally with 60 mg/kg MCT on the first day, and then with the same volume of normal saline every day. Rats in the MCT+PNS group was injected intraperitoneally with 60 mg/kg MCT on the first day, and then with 50 mg/kg PNS every day. The modeling time of each group lasted for 21 days. After the model was established, the mean pulmonary artery pressure (mPAP) was measured by right heart catheterization technique, the right ventricular hypertrophy index (RVHI) was calculated, the microscopic morphology and changes of pulmonary vascular wall were observed by HE and Masson staining, and the expressions of ADAM10, Notch3, Hes-1, P27, PCNA, Caspase-3 proteins and mRNA in pulmonary vascular tissue of rats were detected by Western blot and qPCR. The expression and localization of Notch3 and α-SMA were detected by immunofluorescence staining. The protein expression of ADAM10 was detected by immunohistochemical staining. The results showed that compared with the control group, mPAP, RVHI, pulmonary vessels and collagen fibers in the MCT group were significantly increased, the expressions of ADAM10, Notch3, Hes-1, and PCNA protein and mRNA were significantly increased, while the expressions of P27 and Caspase-3 protein and mRNA were decreased significantly. Compared with the MCT group, mPAP and RVHI were significantly decreased, pulmonary vessels were significantly improved and collagen fibers were significantly reduced, the expressions of protein and mRNA of ADAM10, Notch3, Hes-1, and PCNA were decreased in MCT+PNS group, but the expressions of protein and mRNA of P27 and Caspase-3 were increased slightly. The results of immunofluorescence showed that Notch3 and α-SMA staining could overlap, which proved that Notch3 was expressed in smooth muscle cells. The expression of Notch3 in the MCT group was increased significantly compared with that in the control group, while PNS intervention decreased the expression of Notch3. Immunohistochemical staining showed that compared with the control group, the amount of ADAM10 in the MCT group was increased significantly, and the expression of ADAM10 in the MCT+PNS group was decreased compared with the MCT group. These results indicate that PNS can improve the PAH induced by MCT in rats by inhibiting ADAM10/Notch3 signaling pathway.
Animals
;
Male
;
Rats
;
Caspase 3/metabolism*
;
Collagen
;
Disease Models, Animal
;
Hypertension, Pulmonary/drug therapy*
;
Monocrotaline/adverse effects*
;
Panax notoginseng/chemistry*
;
Proliferating Cell Nuclear Antigen/pharmacology*
;
Pulmonary Arterial Hypertension
;
Pulmonary Artery/metabolism*
;
Rats, Sprague-Dawley
;
Receptor, Notch3/genetics*
;
RNA, Messenger
;
Saline Solution
;
Signal Transduction
;
Saponins/pharmacology*
7.Clinical Features of Collagenous Gastritis.
Long-Jiao CAI ; Yuan LIU ; Ai-Min LENG
Acta Academiae Medicinae Sinicae 2023;45(6):902-911
Objective To analyze the clinical characteristics of collagenous gastritis (CG) and provide evidence for the precise diagnosis and treatment of CG.Methods Published case reports and case series were collected from PubMed,CNKI,and Wanfang Med Online with the key words of collagenous gastritis,collagenous gastroduodenitis,collagenous gastrointestinal diseases,and gastric mucosal nodules.The demographic and clinical information of each case was collected.Results According to the extent of collagen deposition in the digestive tract,94 CG cases included in this study were assigned into upper digestive tract (UDT)-CG,total digestive tract (TDT)-CG and other groups.The UDT-CG group included 52 cases (57.69% females and 42.31% males) with a median age of 14.50 (11.00,25.75) years old.There were 17 cases in the TDT-CG group,including 70.59% females and 29.41% males,with a median age of 15.00 (9.50,48.50) years old.The other group contained 25 cases,(64.00% females and 36.00% males) with a median age of 25.00 (15.50,59.50) years old.The main clinical manifestations in the UDT-CG group were anemia (59.62%) and diarrhea (17.31%),and those in the TDT-CG group were anemia (29.41%) and diarrhea (94.12%).The nodular appearance of gastric mucosa was observed in 75.00% cases in the UDT-CG group and 35.29% cases in the TDT-CG group.In the initial treatment,symptomatic therapy and hormonal therapy respectively relieved the symptoms in 75.00% (30/40) and 100% (3/3) cases in the UDT-CG group and 57.14% (4/7) and 83.33% (5/6) cases in the TDT-CG group.In the retreatment,symptomatic therapy and hormone therapy respectively achieved the remission rates of 100.00% (3/3) and 88.89% (8/9) in the UDT-CG group and 80.00% (4/5) and 66.67% (2/3) in the TDT-CG group.Conclusions CG,a rare disease of gastric collagen deposition,mainly occurs in young patients,and females are more susceptible than males.The clinical manifestations of CG are nonspecific,and anemia,abdominal pain,diarrhea,weight loss,and gastrointestinal bleeding are the common symptoms of CG.Nodular appearance of gastric mucosa is a relatively specific endoscopic feature of CG.There is no standardized treatment for CG.Symptomatic treatment is commonly adopted to improve the quality of life of the patients,and hormones can be added when necessary.
Male
;
Female
;
Humans
;
Quality of Life
;
Gastritis/diagnosis*
;
Gastric Mucosa
;
Collagen
;
Anemia/etiology*
;
Diarrhea/complications*
8.Effects and mechanisms of total flavones of Abelmoschus manihot in inhibiting podocyte necroptosis and renal fibrosis in diabetic kidney disease.
Jia-Xin CHEN ; Qi-Jun FANG ; Yi-Gang WAN ; Ying-Lu LIU ; Yu WANG ; Wei WU ; Yue TU ; Mei-Zi WANG ; Dian-Guang WANG ; Hai-Tao GE
China Journal of Chinese Materia Medica 2023;48(15):4137-4146
Previous studies have shown that high blood glucose-induced chronic microinflammation can cause inflammatory podocyte injury in patients with diabetic kidney disease(DKD). Therein, necroptosis is a new form of podocyte death that is closely associated with renal fibrosis(RF). To explore the effects and mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese herbal medicine Abelmoschus manihot for treating kidney diseases, on podocyte necroptosis and RF in DKD, and to further reveal its scientific connotation with multi-pathway and multi-target, the authors randomly divided all rats into four groups: a namely normal group, a model group, a TFA group and a rapamycin(RAP) group. After the modified DKD rat models were successfully established, four group rats were given double-distilled water, TFA suspension and RAP suspension, respectively by gavage every day. At the end of the 4th week of drug treatment, all rats were sacrificed, and the samples of their urine, blood and kidneys were collected. And then, the various indicators related to podocyte necroptosis and RF in the DKD model rats were observed, detected and analyzed, respectively. The results indicated that, general condition, body weight(BW), serum creatinine(Scr), urinary albumin(UAlb), and kidney hypertrophy index(KHI) in these modified DKD model rats were both improved by TFA and RAP. Indicators of RF, including glomerular histomorphological characteristics, fibronectin(FN) and collagen type Ⅰ(collagen Ⅰ) staining extent in glomeruli, as well as the protein expression levels of FN, collagen Ⅰ, transforming growth factor-β1(TGF-β1) and Smad2/3 in the kidneys were improved respectively by TFA and RAP. Podocyte damage, including foot process form and the protein expression levels of podocin and CD2AP in the kidneys was improved by TFA and RAP. In addition, tumor necrosis factor-α(TNF-α)-mediated podocyte necroptosis in the kidneys, including the morphological characteristics of podocyte necroptosis, the extent and levels of the protein expression of TNF-α and phosphorylated mixed lineage kinase domain like pseudokinase(p-MLKL) was improved respectively by TFA and RAP. Among them, RAP had the better effect on p-MLKL. More importantly, the activation of the receptor interacting serine/threonine protein kinase 1(RIPK1)/RIPK3/MLKL signaling axis in the kidneys, including the expression levels of its key signaling molecules, such as phosphorylated receptor interacting serine/threonine protein kinase 1(p-RIPK1), p-RIPK3, p-MLKL and cysteinyl aspartate specific proteinase-8(caspase-8) was improved respectively by TFA and RAP. Among them, the effect of TFA on p-RIPK1 was superior. On the whole, in this study, the authors demonstrated that TFA alleviates podocyte necroptosis and RF in DKD through inhibiting the activation of the TNF-α-mediated RIPK1/RIPK3/MLKL signaling axis in diabetic kidneys. The authors' findings provide new pharmacological evidence to reveal the scientific connotation of TFA in treating RF in DKD in more depth.
Humans
;
Rats
;
Animals
;
Diabetic Nephropathies/drug therapy*
;
Abelmoschus
;
Flavones/pharmacology*
;
Podocytes
;
Tumor Necrosis Factor-alpha/metabolism*
;
Necroptosis
;
Receptor-Interacting Protein Serine-Threonine Kinases/metabolism*
;
Fibrosis
;
Threonine/pharmacology*
;
Collagen/metabolism*
;
Serine/pharmacology*
;
Diabetes Mellitus/drug therapy*
9.Cangxi Tongbi Capsules promote chondrocyte autophagy by regulating circRNA_0008365/miR-1271/p38 MAPK pathway to inhibit development of knee osteoarthritis.
Wen-Peng XIE ; Teng MA ; Yan-Chen LIANG ; Xiang-Peng WANG ; Rong-Xiu BI ; Wei-Guo WANG ; Yong-Kui ZHANG
China Journal of Chinese Materia Medica 2023;48(18):4843-4851
To investigate the mechanism by which Cangxi Tongbi Capsules promote chondrocyte autophagy to inhibit knee osteoarthritis(KOA) progression by regulating the circRNA_0008365/miR-1271/p38 mitogen-activated protein kinase(MAPK) pathway. The cell and animal models of KOA were established and intervened with Cangxi Tongbi Capsules, si-circRNA_0008365, si-NC, and Cangxi Tongbi Capsules combined with si-circRNA_0008365. Flow cytometry and transmission electron microscopy were employed to determine the level of apoptosis and observe autophagosomes, respectively. Western blot was employed to reveal the changes in the protein levels of microtubule-associated protein light chain 3(LC3)Ⅱ/Ⅰ, Beclin-1, selective autophagy junction protein p62/sequestosome 1, collagen Ⅱ, a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS-5), and p38 MAPK. The mRNA levels of circRNA_0008365, miR-1271, collagen Ⅱ, and ADAMTS-5 were determined by qRT-PCR. Hematoxylin-eosin staining was employed to reveal the pathological changes of the cartilage tissue of the knee, and enzyme-linked immunosorbent assay to measure the levels of interleukin-1β(IL-1β) and tumor necrosis factor-alpha(TNF-α). The chondrocytes treated with IL-1β showed down-regulated expression of circRNA_0008365, up-regulated expression of miR-1271 and p38 MAPK, lowered autophagy level, increased apoptosis rate, and accelerated catabolism of extracellular matrix. The intervention with Cangxi Tongbi Capsules up-regulated the expression of circRNA_0008365, down-regulated the expression of miR-1271 and p38 MAPK, increased the autophagy level, decreased the apoptosis rate, and weakened the catabolism of extracellular matrix. However, the effect of Cangxi Tongbi Capsules was suppressed after interfering with circRNA_0008365. The in vivo experiments showed that Cangxi Tongbi Capsules dose-dependently inhibited the p38 MAPK pathway, enhanced chondrocyte autophagy, and mitigated articular cartilage damage and inflammatory response, thereby inhibiting the progression of KOA in rats. This study indicated that Cangxi Tongbi Capsules promoted chondrocyte autophagy by regulating the circRNA_0008365/miR-1271/p38 MAPK pathway to inhibit the development of KOA.
Rats
;
Animals
;
Chondrocytes
;
Osteoarthritis, Knee/pathology*
;
RNA, Circular/pharmacology*
;
p38 Mitogen-Activated Protein Kinases/metabolism*
;
MicroRNAs/metabolism*
;
Apoptosis
;
Autophagy/genetics*
;
Collagen/metabolism*
10.Liver targeting of compound liposomes mediated by glycyrrhetinic acid derivative receptor and its effect on hepatic stellate cells.
Xiu-Li WANG ; Hui-da GUAN ; Shu-Xian QU ; Bo-Wen XUE ; Geng LI ; Xing-Yu LIU ; Li-Sha CHEN ; Heng GU
China Journal of Chinese Materia Medica 2023;48(19):5195-5204
The 3-succinate-30-stearyl glycyrrhetinic acid(18-GA-Suc) was inserted into glycyrrhetinic acid(GA)-tanshinone Ⅱ_A(TSN)-salvianolic acid B(Sal B) liposome(GTS-lip) to prepare liver targeting compound liposome(Suc-GTS-lip) mediated by GA receptors. Next, pharmacokinetics and tissue distribution of Suc-GTS-lip and GTS-lip were compared by UPLC, and in vivo imaging tracking of Suc-GTS-lip was conducted. The authors investigated the effect of Suc-GTS-lip on the proliferation inhibition of hepatic stellate cells(HSC) and explored their molecular mechanism of improving liver fibrosis. Pharmacokinetic results showed that the AUC_(Sal B) decreased from(636.06±27.73) μg·h·mL~(-1) to(550.39±12.34) μg·h·mL~(-1), and the AUC_(TSN) decreased from(1.08±0.72) μg·h·mL~(-1) to(0.65±0.04) μg·h·mL~(-1), but the AUC_(GA) increased from(43.64±3.10) μg·h·mL~(-1) to(96.21±3.75) μg·h·mL~(-1). The results of tissue distribution showed that the AUC_(Sal B) and C_(max) of Sal B in the liver of the Suc-GTS-lip group were 10.21 and 4.44 times those of the GTS-lip group, respectively. The liver targeting efficiency of Sal B, TSN, and GA in the Suc-GTS-lip group was 40.66%, 3.06%, and 22.08%, respectively. In vivo imaging studies showed that the modified liposomes tended to accumulate in the liver. MTT results showed that Suc-GTS-lip could significantly inhibit the proliferation of HSC, and RT-PCR results showed that the expression of MMP-1 was significantly increased in all groups, but that of TIMP-1 and TIMP-2 was significantly decreased. The mRNA expressions of collagen-I and collagen-Ⅲ were significantly decreased in all groups. The experimental results showed that Suc-GTS-lip had liver targeting, and it could inhibit the proliferation of HSC and induce their apoptosis, which provided the experimental basis for the targeted treatment of liver fibrosis by Suc-GTS-lip.
Humans
;
Liposomes
;
Hepatic Stellate Cells
;
Glycyrrhetinic Acid/pharmacology*
;
Liver
;
Liver Cirrhosis/genetics*
;
Collagen/pharmacology*


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