1.Effects and mechanisms of swimming for inhibiting traumatic joint contracture in a rat model
Xiaoping SHUI ; Chunying LI ; Xin ZHANG ; Bin LI ; Chao FENG ; Hongyu ZHOU ; Ke CHEN ; Yingying LIAO
Chinese Journal of Tissue Engineering Research 2025;29(2):262-268
BACKGROUND:Early exercise treatment is the main prevention way for traumatic joint contracture and is also a research focus.Swimming may be a potential intervention for joint contracture due to the special physical properties of water. OBJECTIVE:To explore the effects of swimming on the development of joint contracture in a rat model and study its mechanisms. METHODS:Twenty-four Sprague-Dawley rats were randomly divided into a blank control group(n=8)and a joint contracture group(n=16).After the surgical operation of knee joint contracture rat models,the joint contracture group was randomly subdivided into a surgical control group(n=8)and a swimming treatment group(n=8).Swimming started in the swimming treatment group in the second week after surgery and lasted for a total of 5 weeks.At the 6th week after surgery,the body mass,knee joint range of motion,and quadriceps diameter were tested,and the diameter/body mass index was calculated.Hematoxylin-eosin staining was performed to detect the pathological changes in the knee joint capsule and quadriceps muscle,and Masson staining was used to observe fibrotic changes in the knee joint capsule.Furthermore,the protein expression of transforming growth factor β1 and type I collagen in the knee joint capsule was quantified by immunohistochemical assay and western blot was performed to detect the protein expression of MuRF1 in the quadriceps femoris. RESULTS AND CONCLUSION:Compared with the blank control group,the knee range of motion decreased in the surgical control and swimming treatment groups(P<0.01),and knee extension deficit and arthrogenic extension deficit were significantly increased(P<0.01),the diameter of the quadriceps muscle was decreased(P<0.01),the joint capsule showed significant fibrosis,the quadriceps muscle was atrophied,and the diameter/body mass index was decreased(P<0.01).Compared with the surgical control group,the swimming treatment group showed a significant increase in knee joint range of motion and quadriceps diameter(P<0.01),and significant improvement in joint capsule fibrosis and quadriceps atrophy.Compared with the blank control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen were increased in the joint capsule of rats in both the surgical control group and the swimming treatment group(P<0.01).Compared with the surgical control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen protein in the joint capsule were decreased in the swimming treatment group.Compared with the blank control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the surgical control group and the swimming treatment group was increased(P<0.05).Compared with the surgical control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the swimming treatment group was decreased(P<0.05).To conclude,early swimming intervention reduces transforming growth factor β1 and type I collagen expression in the joint capsule of traumatic joint contracture rats,decreases MuRF1 expression in the quadriceps muscle,and increases joint range of motion and quadriceps diameter,thereby inhibiting the development of joint contracture.
2.Improvement effect and mechanism of salidroside on radiation-induced parotid gland injury in rats by VIP-cAMP pathway
Chunying ZHANG ; Guangwei YIN ; Hong CHEN ; Mingda YOU ; Jinfeng LIU ; Yakun ZHANG ; Yaojie HU
China Pharmacy 2025;36(22):2796-2801
OBJECTIVE To explore the improvement effect and mechanism of salidroside on radiation-induced parotid gland injury in rats. METHODS Rats were randomly assigned into normal group, radiation group, salidroside low-dose (salidroside-L, 50 mg/kg) group, salidroside high-dose (salidroside-H, 100 mg/kg) group, and salidroside-H+inhibitor (100 mg/kg salidroside+0.1 µmol/kg H-89) group, with 10 rats in each group. Except for the normal group, rats in the other groups were subjected to radiation exposure to establish a model of radiation-induced parotid gland injury. Rats in each group were intraperitoneally injected with the corresponding drug or normal saline, once a day, for 40 consecutive days. After the last administration, the levels of reactive oxygen species (ROS), cyclic adenosine monophosphate (cAMP), superoxide dismutase (SOD), and amylase in serum were detected; the pathological changes of parotid gland tissue were observed; the apoptosis rate of parotid gland tissue cells, the expression levels of B-cell lymphoma-2 (Bcl-2) and its associated X protein (Bax), mRNA expression levels of interleukin-6 (IL- 6) and tumor necrosis factor-α (TNF-α), the protein expression levels of type Ⅲ collagen (Col Ⅲ), vasoactive intestinal peptide (VIP), and the phosphorylation level of protein kinase A (PKA) in parotid gland tissue were determined. RESULTS Compared with normal group, the levels of ROS, amylase, apoptosis rate, Bax expression level, mRNA expression levels of IL-6 and TNF- α, and protein expression level of Col Ⅲ in the radiation group were significantly increased, while the levels of cAMP, SOD, Bcl-2 expression level, VIP protein expression level and PKA phosphorylation level were significantly decreased (P<0.05). Compared with radiation group, the above indicators in the salidroside-L group and salidroside-H group were significantly improved (P<0.05), and the improvement in the salidroside-H group was more significant (P<0.05); inhibitor H-89 significantly reversed the changes in the above indicators of the salidroside-H group (P<0.05). CONCLUSIONS Salidroside can effectively alleviate radiation-induced parotid gland injury in rats, and its mechanism may be related to the activation of the VIP-cAMP pathway.
3.Metabolic reconfiguration in vitiligo: progress and future
Chunying LI ; Jianru CHEN ; Shuli LI
Chinese Journal of Dermatology 2024;57(1):8-11
Based on the results of the latest basic research on vitiligo, this article elucidates the significance of reconfiguration of glucose metabolism, lipid metabolism, amino acid metabolism, and metabolism of gut microbiota in the pathogenesis of vitiligo, attempts to delineate a panoramic picture of metabolic reconfiguration in vitiligo, and discusses the importance of dialectically and uniformly grasping the crosstalk between multiple metabolic pathways, and of thinking about the mechanisms of action of multiple metabolic pathway reconfiguration in the occurrence of vitiligo in individuals from a holistic perspective in future basic studies, in order to promote the understanding of the vitiligo pathogenesis and explore potential treatment methods for vitiligo.
4.Comparison of the efficacy of water jet-assisted dermabrasion versus electric dermabrasion in combination with suction blister epidermal grafting in the treatment of vitiligo
Hui CHEN ; Bing LI ; Chunying LI ; Weinan GUO
Chinese Journal of Dermatology 2024;57(1):43-45
Objective:To compare the clinical efficacy and safety of water jet-assisted dermabrasion versus electric dermabrasion in combination with suction blister epidermal grafting in the treatment of vitiligo.Methods:A total of 60 vitiligo patients were enrolled from the Department of Dermatology, Xijing Hospital from March 2020 to March 2022. Thirty patients firstly received water jet-assisted dermabrasion, 30 firstly received electric dermabrasion, and then all were treated with suction blister epidermal grafting. Follow-up visits were conducted once a month, and the repigmentation of skin lesions and efficacy were evaluated and compared between the two groups 6 months after surgery.Results:There were 30 patients with 312 skin lesions in the water jet-assisted dermabrasion group, including 13 males and 17 females, with the ages and disease duration being 24.41 ± 3.12 years and 5.13 ± 2.34 years respectively; there were 30 patients with 301 skin lesions in the electric dermabrasion group, including 11 males and 19 females, with the ages and disease duration being 22.73 ± 5.11 years and 4.88 ± 2.21 years respectively. No significant differences were observed in the age, gender, disease duration, and dermabrasion sites between the two groups (all P > 0.05). Six months after the operation, 187 (59.94%) skin lesions were healed, 103 (33.01%) were markedly improved, and 22 (7.05%) were improved in the water jet-assisted dermabrasion group; in the electric dermabrasion group, 166 (55.15%) lesions were healed, 108 (35.88%) were markedly improved, and 27 (8.97%) were improved; there was no significant difference in the total response rate between the water jet-assisted dermabrasion group (92.95%) and the electric dermabrasion group (91.03%; χ2 = 0.27, P = 0.602). The water jet-assisted dermabrasion group showed significantly higher degree of repigmentation (90.47% ± 2.53%), matching degree of skin color (3.53 ± 0.21 points), and patient satisfaction scores (3.32 ± 0.27 points) compared with the electric dermabrasion group (82.40% ± 5.33%, 2.71 ± 0.32 points, 2.68 ± 0.41 points, t = 5.30, 8.28, 5.09, respectively, all P < 0.05). No adverse reactions/events were seen in either group. Conclusions:The water jet-assisted dermabrasion combined with suction blister epidermal grafting and electric dermabrasion combined with suction blister epidermal grafting showed similar efficacy in the treatment of vitiligo, with good safety profiles. However, the degree of repigmentation, matching degree of skin color, and patient satisfaction rates were all higher in the patients receiving water jet-assisted dermabrasion than those receiving electric dermabrasion.
5.Analysis of depression-like behavioral performances of mouse models of vitiligo
Weiwei SUN ; Jianru CHEN ; Shuli LI ; Tianwen GAO ; Chunying LI
Chinese Journal of Dermatology 2024;57(2):147-154
Objective:To observe and analyze depression-like behavioral performances of mouse models of vitiligo.Methods:Fifteen female C57BL/6 mice aged about 9 weeks were modeled for vitiligo. Whether the mouse models of vitiligo were successfully constructed or not was determined by macroscopy and full-thickness epidermal immunofluorescence staining of mouse tail tissues on day 23 after the start of the experiment; on day 8 (pre-modeling stage) and day 21 (early modeling stage), the elevated plus maze test and the open field test were used to evaluate the behavioral performances of the mice, including the number of entry into the open arms, percentages of time spent in the open arms, percentages of time spent in the central area and total distance traveled, aiming to assess whether depression-like behaviors were exhibited in the mouse models of vitiligo. To further clarify the degree of the impact of vitiligo modeling on the depression-like state in mice, 20 female C57BL/6 mice were equally divided into 2 groups: vitiligo modeling group and vitiligo modeling + chronic restraint stress group; the mice in the vitiligo modeling + chronic restraint stress group were subjected to chronic restraint stress on day 9, that is, these mice were placed in centrifuge tubes and restrained for about 6 hours every day for 28 consecutive days; on days 7, 22, 29 and 38 after the start of vitiligo modeling, the above-mentioned behavioral indicators were determined by the elevated plus maze test and open field test in the 2 groups. Repeated measurement data in a single group were compared before and after treatment by using paired t-test, and repeated measurement data at multiple time points were compared by using two-way repeated measures analysis of variance. Results:By macroscopy, the mice gradually developed well-defined white patches on the tail skin during vitiligo modeling, which were similar to the clinical manifestations of vitiligo patients; on day 23, full-thickness epidermal immunofluorescence staining of the mouse tail tissues was conducted and showed obvious infiltration of CD8 + T cells and a decrease in the number of Melan-A-positive epidermal melanocytes under a laser confocal microscope, which were consistent with typical pathological characteristics of vitiligo; based on the macroscopic results and immunofluorescence findings, a total of 12 mouse models of vitiligo were successfully constructed on day 23. The elevated plus maze test showed that the number of entry into the open arms and the percentages of time spent in the open arms were significantly lower in the 12 mouse models of vitiligo on day 21 (2.33 ± 1.78 times, 5.01% ± 5.27%, respectively) than in those on day 8 (10.75 ± 2.30 times, 29.20% ± 12.48%, t = 9.63, 6.36, respectively, both P < 0.001) ; the open field test showed that the percentages of time spent in the central area and total distance traveled were also significantly lower in the mouse models on day 21 (2.31% ± 1.53%, 2 518.31 ± 528.38 cm, respectively) than in those on day 8 (4.47% ± 2.65%, 3 533.45 ± 465.47 cm, t = 2.40, 5.47, P = 0.036, < 0.001, respectively). In the chronic restraint stress test, a total of 14 mouse models of vitiligo were successfully constructed on day 23, including 5 in the vitiligo modeling group and 9 in the vitiligo modeling + chronic restraint stress group. There were no significant differences in the number of entry into the open arms, percentages of time spent in the open arms, percentages of time spent in the central area, and total distance traveled between the vitiligo modeling group and the vitiligo modeling + chronic restraint stress group on days 7, 22, 29, and 38 ( F = 0.21, 0.20, 0.46, 2.35, P = 0.889, 0.893, 0.719, 0.134, respectively) ; moreover, all the above indicators significantly changed over time (all P < 0.001), except for the total distance traveled ( P = 0.422) . Conclusion:The mouse models of vitiligo developed depression-like behavior at the early modeling stage, and the degree of depression could not be further deepened by chronic restraint stress on the basis of vitiligo modeling.
6.Prediction of isocitrate dehydrogenase status of glioma via diffusion tensor imaging parameters and clinical features
Yuxia LIANG ; Yu SHANG ; Yuhan REN ; Xiang LIU ; Chunying REN ; Ming ZHANG ; Chen NIU
Journal of Practical Radiology 2024;40(3):347-351
Objective To noninvasively predict isocitrate dehydrogenase(IDH)status of glioma via combining imaging and clini-cal features before surgery,so as to provide basis for individualized clinical treatment decision.Methods A total of 47 patients with glioma confirmed by pathological and molecular genetic tests were included,including 20 with IDH mutant type and 27 with IDH wild type.After diffusion tensor imaging(DTI)scanning,fractional anisotropy(FA)and mean diffusivity(MD)values of tumor paren-chyma were calculated.Combining DTI parameters with MRI morphological features of tumor,blood neutrophil/lymphocyte ratio(NLR)and patient's age,binary logistic regression model was established to effectively predict IDH status of glioma patients before surgery.Results There were significant differences in FAmean/FANAWM,MDmin,NLR,tumor location and age between IDH mutant type and IDH wild type groups(P<0.05).The binary logistic regression model concluding,FAmean/FANAWM,MDmin,cystic degeneration,NLR and age,predicted IDH status of glioma with area under the curve(AUC)of 0.961 and 95%confidence interval(CI)of 0.914-1.00.Conclusion The regression model established via combining DTI,MRI morphological features and blood NLR has great performance in classifying IDH status of glioma,and can help predict IDH status noninvasively before surgery,so as to assist clinical individualized treatment.
7.Shear wave viscoelastography for differentiating lung peripheral inflammatory masses and malignant tumors
Jiling WEI ; Chunying LI ; Han YUAN ; Hengfei CHEN ; Yong GAO ; Xinhong LIAO
Chinese Journal of Medical Imaging Technology 2024;40(10):1524-1528
Objective To observe the value of shear wave viscoelastography(SWV)for differentiating lung peripheral inflammatory masses and malignant tumors.Methods Conventional gray-scale ultrasound and SWV were prospectively performed in 70 patients with lung peripheral inflammatory mass or malignant tumor.The patients were divided into malignant group(n=42)and inflammatory group(n=28)according to pathological results.Clinical and ultrasonic data,including the maximum diameter of lesions,the mean Young's modulus(Emean),mean viscosity(Vmean),and mean dispersion slope(Dmean)were compared between groups.Receiver operating characteristic curves of ultrasonic parameters being significantly different between groups were drawn,and area under the curves(AUCs)were calculated to evaluate the efficacy of each parameter for differentiating lung peripheral inflammatory mass or malignant tumor.Results In malignant group,the maximum diameter and Emean of lesions were both higher,while Vmean and Dmean of lesions were both lower than those in inflammatory group(all P<0.05).Vmean and Dmean of lesions had moderately/good efficacy for differentiating lung peripheral inflammatory mass or malignant tumor(AUC=0.843,0.866),both better than that of conventional ultrasound and Emean(AUC=0.673,0.685)(all P<0.05).The combination of Emean,Vmean and Dmean had good efficacy for differentiating lung peripheral inflammatory masses and malignant tumors,with AUC of 0.874.Conclusion The viscous parameters of SWV could effectively differentiating lung peripheral inflammatory masses and malignant tumors.
8.Potential of new self-crosslinked hyaluronic acid gel on the recovery of endometrium after artificial abortion: a multicenter, prospective randomized controlled trial
Chunying LI ; Lirong TENG ; Qing LIN ; Liping ZHAO ; Yunxia ZHU ; Xin MI ; Zhenna WANG ; Xiaoye WANG ; Lisong ZHANG ; Dan HAN ; Lili MA ; Wenpei BAI ; Jianmei WANG ; Jun NI ; Huiping SHEN ; Qinfang CHEN ; Hongmei XU ; Chenchen REN ; Jing JIANG ; Guanyuan LIU ; Ping PENG ; Xinyan LIU
Chinese Journal of Obstetrics and Gynecology 2024;59(11):864-870
Objective:To evaluate the impact of self-crosslinked hyaluronic acid (SCH) gel on endometrium recovery after artificial abortion.Methods:A multicenter, prospective randomized controlled trial was conducted across 18 hospitals from December 2021 to February 2023, involving 382 women who underwent artificial abortion. Participants were randomly allocated to receive either treatment with SCH gel (SCH group) or no treatment (control group) in a 1∶1 ratio. The primary outcome was endometrium thickness in 14 to 18 days after the first postoperative menstruation. Secondary outcomes included changes in menstrual volume during the first postoperative menstruation, menstruation resumption within 6 postoperative weeks, time to menstruation resumption, duration of the first postoperative menstruation, and incidence of dysmenorrhea.Results:Baseline characteristics of participants were comparable between the two groups (all P>0.05), with 95.3% (182/191) in SCH group and 92.7% (177/191) in the control group completed the study. The postoperative endometrial thickness in SCH group was significantly greater than that in the control group [(9.78±3.15) vs (8.95±2.32) mm; P=0.005]. SCH group also had significantly fewer participants with reduced menstrual volume [23 cases (12.6%, 23/182) vs 31 cases (17.5%, 31/177); P=0.038]. Although SCH group experienced less dysmenorrhea during the first postoperative menstrual period, this difference was not statistically significant [28.5% (51/179) vs 37.1% (65/175); P=0.083]. Outcomes were similar between SCH group and the control group regarding the proportion of participants who resumed menstruation within 6 weeks postoperatively, time to menstruation resumption, and duration of the first postoperative menstruation ( P=0.792, 0.485, and 0.254, respectively). No serious adverse events were observed during the study period, and no adverse events were attributed to SCH gel treatment. Conclusion:The application of SCH gel after artificial abortion is safe and might aid in the recovery of the endometrium.
9.Berberine regulates polarization of macrophages:a mechanistic study based on PI3K/Akt1 signaling pathway
Yushan CHEN ; Tingting WANG ; Zhonghua MENG ; Shasha SHANG ; Junmeng ZHENG ; Yonghua ZONG ; Chunying SI ; Yazhou LIANG ; Huaimin GUAN
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2024;26(6):694-698
Objective To explore the effect and possible mechanism of berberine on the macro-phage polarization of human myeloid leukemia monocytic cell line THP-1 induced by oxidized low-density lipoprotein(ox-LDL).Methods THP-1 cells were induced into macrophages by PMA,and then according to different concentrations of berberine,the cells were divided into con-trol group,and 5,10,20,40 and 50 μmol/L berberine groups.After intervention for 24 or 48 h,CCK8 assay was used to detect cell viability for optimal concentration and time of berberine treat-ment.PMA-induced THP-1 macrophages were assigned into blank group,model group(ox-LDL),berberine group,inhibitor group(phosphatidyl inositol 3-kinase(PI3K)inhibitor LY294002)and berberine+inhibitor group(berberine+LY294002).The contents of inducible nitric oxide syn-thase(iNOS)and TGF-β1 were detected by ELISA.qPCR was employed to measure the mRNA expression of TNF-α,arginase 1(Arg1),PI3K and protein kinase B Akt1,and Western blotting was applied to detect the protein levels of Akt1 and phosphorylated protein kinase B antibody(p-Akt1).Results In 24 h after intervention,the macrophage activity was significantly lower in the 40 and 50 μmol/L berberine groups than the control group(P<0.05),and after 48 h,the ac-tivity in all the 5 doses of berberine groups was obviously lower than that in the control group[(0.89±0.02)%,(0.82±0.03)%,(0.71±0.02)%,(0.62±0.03)%and(0.53±0.02)%vs(1.01±0.01)%,P<0.05].Berberine treatment of 20 μmol/L for 24 h had little effect on cell viability,and the dose and the time were regarded as the best concentration and time.Compared with the blank group,iNOS content and TNF-α mRNA level were increased in the model group,while TGF-β1 content,mRNA levels of Arg1,PI3K and Akt1,and p-Akt1/Akt1 protein levels were de-creased(P<0.05).iNOS content and TNF-α mRNA level were decreased,while TGF-β1 content,mRNA levels of Arg1,PI3K and Akt1 and protein levels of p-Akt1/Akt1s were increased in the berberine group than the model group(P<0.05).Compared with the berberine group,iNOS con-tent and TNF-α mRNA level were increased,while mRNA levels of Arg1,PI3K and Akt1 and protein levels of p-Akt1/Akt1 were decreased in the berberine+inhibitor group(P<0.05).Con-clusion Berberine can inhibit the inflammatory response of THP-1 macrophages induced by ox-LDL by activating PI3K/Akt1 pathway,and inhibit the M1 polarization and promote the M2 polarization of macrophages.
10.Study on the protective effect of folic acid against oxidative stress-induced damage to melanocytes in vitro
Jiaxi CHEN ; Xiuli YI ; Chunying LI ; Shuli LI
Chinese Journal of Dermatology 2024;57(6):547-552
Objective:To investigate the protective effect of folic acid on melanocytes under oxidative stress.Methods:The normal human melanocyte cell line (PIG1) was cultured in vitro and divided into 5 groups to receive corresponding treatments: control group (normal culture for 48 hours without other treatment), H 2O 2 treatment group (normal culture for 24 hours followed by the treatment with 1 mmol/L H 2O 2 for another 24 hours), and 3 folic acid pretreatment groups (pretreatment with folic acid at concentrations of 50, 125, and 250 μmol/L for 24 hours followed by the treatment with 1 mmol/L H 2O 2 for another 24 hours). The cell viability was assessed using the cell counting kit 8 (CCK8) assay, the intracellular melanin content was measured by the sodium hydroxide solubilization method, cell apoptosis rates were detected by annexin V-fluorescein isothiocyanate/propidium iodide double staining, levels of intracellular reactive oxygen species (ROS) were detected using the fluorescent probe CM-H2DCFDA, the mitochondrial membrane potential was determined using the fluorescent probe JC-1, and the mitochondrial ultrastructure was observed by transmission electron microscopy. Comparisons among multiple groups were performed using one-way analysis of variance, and multiple comparisons were performed using Tukey test. Results:Compared with the control group, the H 2O 2 treatment group showed decreased cell viability (83.62% ± 3.77% vs. 99.99% ± 5.06%, P = 0.031), intracellular melanin content (68.48% ± 4.17% vs. 100.11% ± 2.30%, P < 0.001) and mitochondrial membrane potential (2.96 ± 0.26 vs. 5.86 ± 0.56, P = 0.002), but increased cell apoptosis rate (16.35% ± 1.20% vs. 6.45% ± 1.34%, P = 0.001) and intracellular ROS level (138.98% ± 2.74% vs. 100.00% ± 0.64%, P = 0.004). Compared with the H 2O 2 treatment group, the 125-μmol/L and 250-μmol/L folic acid pretreatment groups showed increased cell viability (106.21% ± 6.34%, 101.64% ± 6.77%, respectively; both P < 0.05) and intracellular melanin content (77.24% ± 3.85%, 88.34% ± 2.65%, respectively; both P < 0.05) ; the 50-μmol/L, 125-μmol/L and 250-μmol/L folic acid pretreatment groups all showed decreased cell apoptosis rates (9.40% ± 0.99%, 9.00% ± 1.13%, 6.50% ± 0.28%, P = 0.007, 0.005, 0.001, respectively) ; the 125-μmol/L and 250-μmol/L folic acid pretreatment groups showed decreased intracellular ROS levels (112.99% ± 4.21%, 101.36% ± 10.60%, P = 0.023, 0.005, respectively), but increased mitochondrial membrane potential (4.93 ± 0.25, 5.67 ± 0.35, P = 0.012, 0.003, respectively). Transmission electron microscopy showed damaged mitochondrial ultrastructure in melanocytes in the H 2O 2 treatment group, characterized by a substantial number of vacuolated mitochondria, intimal swelling, and reduced ridges, compared with the control group; compared with the H 2O 2 treatment group, the 250-μmol/L folic acid pretreatment group exhibited decreased degree of mitochondrial damage, manifesting as reduced mitochondrial vacuolization, clearer mitochondrial ultrastructure, and slight swelling of mitochondrial ridges. Conclusion:Folic acid could reduce the oxidative stress level in melanocytes, thus protecting melanocytes from oxidative stress.

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