1.Research progress on enhancing osseointegration properties of polyetheretherketone implants through various modification methods.
Shilai LIU ; Xiaoke FENG ; Chunxia CHEN
Journal of Biomedical Engineering 2025;42(2):417-422
This review article summarizes the current modification methods employed to enhance the osseointegration properties of polyetheretherketone (PEEK), a novel biomaterial. Our analysis highlights that strategies such as surface treatment, surface modification, and the incorporation of bioactive composites can markedly improve the bioactivity of PEEK surfaces, thus facilitating their effective integration with bone tissue. However, to ensure widespread application of PEEK in the medical field, particularly in oral implantology, additional experiments and long-term clinical evaluations are required. Looking ahead, future research should concentrate on developing innovative modification techniques and assessment methodologies to further optimize the performance of PEEK implant materials. The ultimate goal is to provide the clinical setting with even more reliable solutions.
Benzophenones
;
Ketones/chemistry*
;
Polyethylene Glycols/chemistry*
;
Osseointegration
;
Humans
;
Polymers
;
Biocompatible Materials/chemistry*
;
Surface Properties
;
Prostheses and Implants
;
Dental Implants
2.Effectiveness comparison of anterior cervical discectomy and fusion with zero-profile three-dimensional-printed interbody fusion Cage and titanium plate fusion Cage.
Yuwei LI ; Xiuzhi LI ; Bowen LI ; Yunling GU ; Tiantian YANG ; Lei ZHAO ; Wei CUI ; Shifeng GU ; Haijiao WANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(9):1187-1195
OBJECTIVE:
To compare the effectiveness of a zero-profile three-dimensiaonal (3D)-printed microporous titanium alloy Cage and a conventional titanium plate combined with a polyether-ether-ketone (PEEK)-Cage in the treatment of single-segment cervical spondylotic myelopathy (CSM) by anterior cervical discectomy and fusion (ACDF).
METHODS:
The clinical data of 83 patients with single-segment CSM treated with ACDF between January 2022 and January 2023 were retrospectively analyzed, and they were divided into 3D-ZP group (35 cases, using zero-profile 3D-printed microporous titanium alloy Cage) and CP group (48 cases, using titanium plate in combination with PEEK-Cage). There was no significant difference in gender, age, disease duration, surgical intervertebral space, and preoperative Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score, neck disability index (NDI), vertebral height at the fusion segment, Cobb angle, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stay, complications, interbody fusion, and prosthesis subsidence were recorded and compared between the two groups. VAS score, NDI, and JOA score were used to evaluate the improvement of pain and function before operation, at 3 months after operation, and at last follow-up, and the vertebral height at the fusion segment and Cobb angle were measured by imaging. The degree of dysphagia was assessed by the Bazaz dysphagia scale at 1 week and at last follow-up.
RESULTS:
The operation was successfully completed in all the 83 patients. There was no significant difference in intraoperative blood loss and hospital stay between the two groups (P>0.05), but the operation time in the 3D-ZP group was significantly shorter than that in the CP group (P<0.05). Patients in both groups were followed up 24-35 months, with an average of 25.3 months, and there was no significant difference in the follow-up time between the two groups (P>0.05). The incidence and grade of dysphagia in CP group were significantly higher than those in 3D-ZP group at 1 week after operation and at last follow-up (P<0.05). There was no dysphagia in 3D-ZP group at last follow-up. There was no complication such as implant breakage or displacement in both groups. The intervertebral fusion rates of 3D-ZP group and CP group were 65.71% (23/35) and 60.42% (29/48) respectively at 3 months after operation, and there was no significant difference between the two groups [OR (95%CI)=1.256 (0.507, 3.109), P=0.622]. The JOA score, VAS score, and NDI significantly improved in the 3D-ZP group at 3 months and at last follow-up when compared with preoperative ones (P<0.05), but there was no significant difference between the two groups (P>0.05). There was no significant difference in the improvement rate of JOA between the two groups at last follow-up (P>0.05). At 3 months after operation and at last follow-up, the vertebral height at the fusion segment and Cobb angle significantly improved in both groups, and the two indexes in 3D-ZP group were significantly better than those in CP group (P<0.05). At last follow-up, the incidence of prosthesis subsidence in 3D-ZP group (8.57%) was significantly lower than that in CP group (29.16%) (P<0.05).
CONCLUSION
The application of zero-profile 3D-printed Cage and titanium plate combined with PEEK-Cage in single-segment ACDF can both reconstruct the stability of cervical spine and achieve good effectiveness. Compared with the latter, the application of the former in ACDF can shorten the operation time, reduce the incidence of prosthesis subsidence, and reduce the incidence of dysphagia.
Humans
;
Spinal Fusion/instrumentation*
;
Titanium
;
Cervical Vertebrae/surgery*
;
Diskectomy/instrumentation*
;
Bone Plates
;
Male
;
Printing, Three-Dimensional
;
Female
;
Retrospective Studies
;
Middle Aged
;
Treatment Outcome
;
Benzophenones
;
Adult
;
Spondylosis/surgery*
;
Aged
;
Polymers
;
Ketones
;
Polyethylene Glycols
3.Injectable agents for the induction of Peyronie's disease in model rats: a comparative study.
Guang-Jun DU ; Si-Yan XING ; Ning WU ; Tong WANG ; Yue-Hui JIANG ; Tao SONG ; Bai-Bing YANG ; Yu-Tian DAI
Asian Journal of Andrology 2025;27(1):96-100
Peyronie's disease (PD) is a disorder characterized by fibrous plaque formation in the penile tissue that leads to curvature and complications in advanced stages. In this study, we aimed to compare four injectable induction agents for the establishment of a robust rat model of PD: transforming growth factor-β1 (TGF-β1), fibrin, sodium tetradecyl sulfate (STS) combined with TGF-β1, and polidocanol (POL) combined with TGF-β1. The results showed that injection of TGF-β1 or fibrin into the tunica albuginea induced pathological endpoints without causing penile curvature. The STS + TGF-β1 combination resulted in both histological and morphological alterations, but with a high incidence of localized necrosis that led to animal death. The POL + TGF-β1 combination produced pathological changes and curvature comparable to STS + TGF-β1 and led to fewer complications. In conclusion, fibrin, STS + TGF-β1, and POL + TGF-β1 all induced PD with a certain degree of penile curvature and histological fibrosis in rats. The POL + TGF-β1 combination offered comparatively greater safety and clinical relevance and may have the greatest potential for PD research using model rats.
Animals
;
Male
;
Penile Induration/drug therapy*
;
Rats
;
Transforming Growth Factor beta1/metabolism*
;
Disease Models, Animal
;
Fibrin
;
Penis/drug effects*
;
Polidocanol/administration & dosage*
;
Rats, Sprague-Dawley
;
Polyethylene Glycols/administration & dosage*
;
Injections
4.Clinical Characteristics and Prognosis Analysis of Patients with Extranasal NK/T-Cell Lymphoma: A Multicenter Retrospective Study of Huaihai Lymphoma Working Group.
Hui-Rong SHAN ; Qing ZHANG ; Ling WANG ; Yu-Ye SHI ; Yu-Qing MIAO ; Tai-Gang ZHU ; Jing-Jing YE ; Xu-Dong ZHANG ; Liang WANG ; Zi-Yuan SHEN ; Wei SANG
Journal of Experimental Hematology 2025;33(1):93-100
OBJECTIVE:
To explore the clinical characteristics and prognostic factors of patients with extranasal NK/T-cell lymphoma (NKTCL).
METHODS:
The clinical data of 138 patients with NKTCL diagnosed in 10 medical centers of Huaihai Lymphoma Working Group from June 2015 to April 2021 were collected and analyzed retrospectively. The differences in clinicopathological characteristics of patients with different involvement and efficacy of pegaspargase regimen were compared, as well as perform survival analysis.
RESULTS:
A total of 138 extranasal NKTCL patients were included, with a median age of 46 years, and the ratio of males to females was approximately 2∶1. There were 39 patients with gastrointestinal involvement, 32 patients with oropharyngeal involvement, 17 patients with skin involvement, 11 patients with lymph node involvement, 11 patients with orbital involvement, and 28 patients with other parts involvement. Patients with skin involvement had a higher proportion of advanced disease and a lower proportion of CD56 positive rate compared to those with oropharyngeal involvement. Among the patients with gastrointestinal involvement, the survival rate of patients who received pegaspargase regimen was significantly higher than those who were treated without pegaspargase (P < 0.01). Multivariate analysis showed that serum creatinine was an independent prognostic factor for patients with skin involvement ( HR =1.027, 95%CI : 1.001-1.054, P =0.040), ECOG PS and EBV DNA were independent prognostic factors for patients with gastrointestinal involvement ( HR =2.635, 95%CI : 1.096-6.338, P =0.030; HR =4.772, 95% CI : 1.092-20.854, P =0.038), and ECOG PS and CA stage were independent prognostic factors for patients with oropharyngeal involvement ( HR =13.875, 95%CI : 2.517-76.496, P =0.002; HR =20.261, 95%CI : 2.466-166.470, P =0.005).
CONCLUSION
The clinicopathological characteristics of extranasal NKTCL patients with different sites of involvement are vary, and effective individualized treatment need to be further explored.
Adult
;
Aged
;
Female
;
Humans
;
Male
;
Middle Aged
;
Asparaginase/therapeutic use*
;
Lymphoma, Extranodal NK-T-Cell/pathology*
;
Prognosis
;
Retrospective Studies
;
Survival Rate
;
Polyethylene Glycols
5.Research Progress of Ropeginterferon α-2b in Treatment of Myeloproliferative Neoplasm --Review.
Journal of Experimental Hematology 2025;33(1):306-310
Ropeginterferon α-2b (Ropeg), a novel, long-acting pegylated prolene alpha interferon, is the first interferon specifically approved for the treatment of patients with polycythemia vera (PV), and has been found in clinical trials and experience to induce hematologic remission, control disease-related symptoms, and reduce JAK2V617F allelic burden in patients with myeloproliferative neoplasms (MPNs). It has a lower incidence and severity of adverse drug reactions than pegylated interferon alpha and hydroxyurea and a longer dosing interval. Some patients with lowrisk PV and myelofibrosis can benefit from it. This article reviews the latest progress of Ropeg in MPN.
Humans
;
Interferon-alpha/therapeutic use*
;
Myeloproliferative Disorders/drug therapy*
;
Polyethylene Glycols/therapeutic use*
;
Recombinant Proteins/therapeutic use*
;
Interferon alpha-2
;
Polycythemia Vera/drug therapy*
6.Analysis of Real-World Outcomes in Patients with Acute Promyelocytic Leukemia Treated with Arsenic Trioxide and All-trans Retinoic Acid without Chemotherapy.
Jia WANG ; Qian-Shan TAO ; Yi DONG ; Zhi-Min ZHAI
Journal of Experimental Hematology 2025;33(5):1254-1261
OBJECTIVE:
To investigate the effect of non-chemotherapy strategy of retinoic acid (ATRA) combined with arsenic trioxide (ATO) on the survival of patients with acute promyelocytic leukemia (APL).
METHODS:
The data of APL patients with complete information diagnosed in the hematology department of our hospital from June 2009 to November 2024 were retrospective analyzed. All patients in the non-CHT group received ATRA-ATO induction, consolidation and maintenance therapy. Patients in the CHT group received ATRA-ATO+chemotherapy induction therapy, followed by 3 cycles of ATRA-ATO+CHT consolidation therapy and 6-10 cycles of ATRA-ATO maintenance therapy. The primary endpoint was event-free survival (EFS). Secondary endpoints included overall survival (OS), remission rate, differentiation syndrome (DS) and safety.
RESULTS:
There were 182 patients with APL and 15 patients with early death (ED), accounting for 8.24%, which was related to age and risk stratification. There was no significant difference in remission rate between the non-CHT group and the CHT group (P =0.486). As of February 2025, the median follow-up time of patients was 39.5 months. The EFS of the non-CHT group was significantly better than that of the CHT group (P =0.038). There was no significant difference in OS between the two groups (P =0.442). Subgroup analysis showed that EFS in the non-CHT was longer in standard-risk patients (P =0.012). There was no significant difference in EFS (P =0.585) and OS (P =0.473) between the CHT and non-CHT groups in high-risk patients. The incidence of mild DS was 23.6% in the non-CHT group and 23.1% in the CHT group, respectively, with no statistically significant difference(P =0.937). Compared with CHT group, the incidence of serious adverse events was lower in the non-CHT group.
CONCLUSION
The non-chemotherapy regimen of ATRA combined with ATO is a feasible method to cure APL patients.
Humans
;
Leukemia, Promyelocytic, Acute/drug therapy*
;
Arsenic Trioxide/therapeutic use*
;
Tretinoin/administration & dosage*
;
Retrospective Studies
;
Female
;
Treatment Outcome
;
Male
;
Adult
;
Antineoplastic Combined Chemotherapy Protocols/therapeutic use*
;
Middle Aged
;
Remission Induction
7.Associations of serum carotene levels and decline for the ability of attention: a longitudinal study in the Japanese general population.
Hiroshi OKUMIYAMA ; Yoshiki TSUBOI ; Ryosuke FUJII ; Akihiko IWAHARA ; Takeshi HATTA ; Shuntaro SATO ; Hiroya YAMADA ; Koji SUZUKI
Environmental Health and Preventive Medicine 2025;30():58-58
BACKGROUND:
Although serum carotene may contribute to dementia prevention, there is a lack of longitudinal evidence for early cognitive decline before dementia symptoms. The aim of this study was to examine whether serum carotene levels were associated with annually evaluated cognitive trajectories among the Japanese general population.
METHODS:
Among 581 baseline participants, 199 individuals (83 males; mean age [min, max], 62.7 [39, 90] years) who underwent cognitive assessments more than twice after baseline were analyzed. "Attention" levels were assessed using one- and three-target Digit Cancellation Tests (D-CAT1 and D-CAT3). "General cognitive ability" was assessed by the short version of Mini-Mental State Examination (SMMSE). Serum carotenes (α-carotene, β-carotene and lycopene) were measured by high-performance liquid chromatography. After the measurements, we calculated total carotene levels by summing up the levels of all measured carotene. Carotene levels were categorized into three groups for analysis (low: 0%-25%, middle: 25%-75%, and high: 75%-100%). A linear mixed model was used to estimate the slope of the D-CAT score trajectory and to compare it between three categories.
RESULTS:
Compared with the middle carotene group, decline of attention was faster in the D-CAT1 for low β-carotene (β = -3.48, p = 0.035), lycopene (β = -3.10, p = 0.062), and total carotene (β = -4.75, p = 0.003), but not for α-carotene (β = -2.60, p = 0.111). For the D-CAT3, decline of attention was faster in the group of low lycopene (β = -3.17, p = 0.002) and total carotene (β = -2.17, p = 0.037) compared with the middle carotene group, while no clear association for α-carotene (β = -0.67, p = 0.521) and β-carotene (β = -0.64, p = 0.639). There were no clear associations between serum carotene and the SMMSE score.
CONCLUSIONS
These findings suggest low levels of serum lycopene are associated with a decline of attention in the setting of the general population.
Humans
;
Male
;
Carotenoids/blood*
;
Female
;
Longitudinal Studies
;
Middle Aged
;
Japan
;
Aged
;
Adult
;
Aged, 80 and over
;
Attention
;
Lycopene
;
East Asian People
8.Biological activity and antitumor effect of long-acting recombinant human interleukin-2 drug.
Xuejun LIANG ; Fengxia ZHANG ; Ting JIN ; Jingjing ZHU
Journal of Peking University(Health Sciences) 2025;57(2):253-261
OBJECTIVE:
To investigate the biological activity and antitumor effect of pegylated recombinant human interleukin 2 (PEG-rhIL-2) obtained by site-specific conjugation of polyethylene glycol (PEG) with non-natural amino acids, and to explore its antitumor mechanism.
METHODS:
The binding activities of PEG-rhIL-2 at three different sites (T41, Y45, and V91) to human interleukin 2 receptors α (IL-2Rα) and β (IL-2Rβ) and were detected by surface plasmon resonance (SPR) technology. Western blot was used to detect the levels of the Janus kinase-signal transducer and activator of transcription 5 (JAK-STAT5) signaling pathway activated by different doses of rhIL-2 and PEG-rhIL-2 in CTTL-2 and YT cells. Blood was collected after a single administration in mice to detect the drug concentration at different time points and evaluate the pharmacokinetic parameters of Y45-PEG-rhIL-2. Mouse hepatoma cell line Hepa1-6, pancreatic cancer cell line Pan-02, and colon cancer cell line MC-38 were selected. Tumor models were constructed in C57BL/6 mice. Different doses of Y45-PEG-rhIL-2 and excipient control were administrated respectively to evaluate the tumor suppression effect of the drug. In the MC-38 colon cancer model, the tumor suppression effect of Y45-PEG-rhIL-2 combined with anti-programmed death-1 (PD-1) monoclonal antibody was evaluated. Hepa1-6 mouse tumor models were constructed and rhIL-2, Y45-rhIL-2 and Y45-PEG-rhIL-2 were administrated respectively. The proportion of tumor-infiltrating lymphocytes was analyzed by flow cytometry.
RESULTS:
The SPR detection results showed that the binding activities of PEG-rhIL-2 to IL-2Rα/IL-2Rβ were both reduced. The affinity of Y45-PEG-rhIL-2 to IL-2Rα was reduced to approximately 1/250, and its affinity to IL-2Rβ was reduced to 1/3. Western blot results showed that the activity of Y45-PEG-rhIL-2 in stimulating JAK-STAT5 signaling in CTLL-2 cells expressing heterotrimeric IL-2 receptor complex IL-2Rαβγwas reduced to approximately 1/300, while its activity in YT cells expressing heterodimeric IL-2 receptor complex IL-2Rβγwas reduced to approximately 1/3. The pharmacokinetic evaluation after a single dose in the mice showed that the elimination half-life of Y45-PEG-rhIL-2 was 17.7 h. Y45-PEG-rhIL-2 has pharmacokinetic characteristics superior to those of rhIL-2. Y45-PEG-rhIL-2 showed dose-dependent tumor suppression activity, and the combination of Y45-PEG-rhIL-2 and anti-PD-1 antibody had a better tumor-inhibiting effect than the single use of Y45-PEG-rhIL-2 or anti-PD-1 antibody. Flow cytometry analysis demonstrated that 72 h after the administration of Y45-PEG-rhIL-2, the proportion of tumor-infiltrating cytotoxic T lymphocytes (CD8+T cells) increased by 86.84%. At 120 h after administration, the ratio of CD8+T cells to regulatory T cells (Treg) increased by 75.10%.
CONCLUSION
Y45-PEG-rhIL-2 obtained by site-specific conjugation via non-natural amino acids changed its receptor binding activity and inhibited tumor growth in dose-dependent manner in multiple tumor models by regulating CD8+T cells.
Interleukin-2/pharmacokinetics*
;
Animals
;
Mice
;
Humans
;
Recombinant Proteins/pharmacology*
;
Polyethylene Glycols/chemistry*
;
Cell Line, Tumor
;
Antineoplastic Agents/pharmacokinetics*
;
Signal Transduction/drug effects*
;
STAT5 Transcription Factor/metabolism*
;
Interleukin-2 Receptor alpha Subunit/metabolism*
;
Interleukin-2 Receptor beta Subunit/metabolism*
9.Crocin Inhibited Aβ Generation via Modulating APP Processing, Suppressing Endoplasmic Reticulum Stress and Activating Autophagy in N2a/APP Cells.
Zi-Rong LIANG ; Cui-Jun LIN ; Yi-Han LIU ; Qian YUE ; Pui Man HOI
Chinese journal of integrative medicine 2025;31(11):973-981
OBJECTIVE:
To explore the mechanism of crocin, a major active component of Crocus sativus (Zanghonghua), in regulating amyloid beta (Aβ) generation, endoplasmic reticulum (ER) stress, and autophagy in neuronal cells, with potential therapeutic applications in Alzheimer's disease (AD).
METHODS:
Mouse neuroblastoma Neuron2a (N2a) cells stably transfected with the human amyloid precursor protein (APP) Swedish mutant was used as a cellular model for AD (N2a/APP). Control cells were vector transfected (N2a/vector). The effects of 3 different doses of crocin on reactive oxygen species (ROS) generation, cytosolic calcium, and apoptosis were evaluated by flow cytometry. Aβ levels were determined by enzyme-linked immunosorbent assay. APP processing and ER stress proteins expressions were determined by Western blot. Autophagosome formation was evaluated by autophagy detection kit and confocal microscope.
RESULTS:
Crocin inhibited APP expression in N2a/APP cells and promoted α-cleavage of APP processing, while modestly reduced beta-secretase 1 (BACE1) and presenilin 1 (PS1, P<0.05 or P<0.01). ER stress markers, including the binding immunoglobulin protein/78-kD glucose-regulated protein (Bip/GRP78) and C/EBP homologous protein (CHOP), were elevated in N2a/APP cells compared to N2a/vector cells (P<0.05). Crocin could effectively reduce the levels of ER stress (P<0.05 or P<0.01). In addition, crocin enhanced autophagy by promoting formation of autophagosome (P<0.05 or P<0.01).
CONCLUSION
Crocin significantly inhibited Aβ generation by promoting α-cleavage of APP processing, inhibiting ER stress-associated unfolded protein response, and regulating autophagy.
Endoplasmic Reticulum Stress/drug effects*
;
Autophagy/drug effects*
;
Animals
;
Endoplasmic Reticulum Chaperone BiP
;
Mice
;
Amyloid beta-Peptides/metabolism*
;
Amyloid beta-Protein Precursor/metabolism*
;
Carotenoids/pharmacology*
;
Humans
;
Cell Line, Tumor
;
Reactive Oxygen Species/metabolism*
;
Apoptosis/drug effects*
;
Calcium/metabolism*
10.Role of acitretin in regulating glucose and lipid homeostasis in an imiquimod-induced psoriasis model mouse.
Kexin LONG ; Wangqing CHEN ; Manyun MAO ; Wu ZHU
Journal of Central South University(Medical Sciences) 2025;50(3):344-357
OBJECTIVES:
Psoriasis is a chronic inflammatory skin disease often accompanied by comorbidities such as hyperglycemia, insulin resistance, and obesity. Acitretin, as a second-generation retinoid, is used in the treatment of psoriasis. This study aims to explore the role of acitretin on glucose and lipid metabolism in psoriasis.
METHODS:
HepG2 cells were treated with acitretin under high- or low-glucose conditions. mRNA and protein expression levels of glucose transport-related genes were evaluated using real-time reverse transcription PCR (real-time RT-PCR) and Western blotting. Glucose uptake was analyzed by flow cytometry, and intracellular lipid droplet formation was assessed via Oil Red O staining. Healthy adult female BALB/C mice were randomly divided into 3 groups: a control group, an imiquimod (IMQ)-induced psoriasis model group (IMQ group), and an acitretin treatment group. Skin lesions and inflammatory markers were examined, along with changes in body weight, plasma glucose/lipid levels, and transcription of metabolic genes. Islets were isolated from normal and psoriasis-induced mice, and the effect of acitretin on insulin secretion was evaluated in vitro.
RESULTS:
Acitretin treatment increased glucose uptake and lipid droplet synthesis of HepG2 in high-glucose environment, with elevated transcription levels of glucose transport-related genes GLUT1 and GLUT4. Transcription of gluconeogenesis-related gene G6pase decreased, while transcription levels of glycogen synthesis-related genes AKT1 and GSY2 increased (all P<0.05), while acitretin inhibits glucose uptake and promotes gluconeogenesis in low-glucose environment. In vivo experiments revealed that compared with the control group, the blood glucose level in the IMQ group was significantly decreased (P<0.05), while acitretin treatment partially restored glucose homeostasis and alleviated weight loss. Ex vivo culture of islets from psoriatic mice revealed that acitretin reduced elevated insulin secretion and downregulated PDX-1 expression, while upregulating glucose homeostasis gene SIRT1 and insulin sensitivity gene PPARγ (all P<0.05). These findings suggest that acitretin plays a critical role in improving islet function and restoring islet homeostasis.
CONCLUSIONS
Acitretin helps maintain the balance between hepatic glycogenesis and gluconeogenesis, enhances insulin sensitivity, and improves pancreatic islet function, thereby promoting systemic and cellular glucose homeostasis.
Acitretin/therapeutic use*
;
Psoriasis/drug therapy*
;
Animals
;
Imiquimod
;
Humans
;
Glucose/metabolism*
;
Homeostasis/drug effects*
;
Mice
;
Lipid Metabolism/drug effects*
;
Mice, Inbred BALB C
;
Female
;
Hep G2 Cells
;
Disease Models, Animal

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