1.The Regulatory Effects and Mechanisms of Piezo1 Channel on Chondrocytes and Bone Metabolic Dysregulation in Osteoarthritis
Yan LI ; Tao LIU ; Yu-Biao GU ; Hui-Qing TIAN ; Lei ZHANG ; Bi-Hui BAI ; Zhi-Jun HE ; Wen CHEN ; Jin-Peng LI ; Fei LI
Progress in Biochemistry and Biophysics 2026;53(3):564-576
Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca2+, K+, and Na+, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca2+ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca2+ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca2+ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.
2.Comparison of Efficacy and Mechanism in Warming Yang and Dispersing Cold of Aconiti Radix Lateralis Praeparata Processed by ZHANG Zhongjing's Method and Pharmacopoeia Method
Mingjie JIAO ; Qian CHEN ; Shuyu YAN ; Yiyan SONG ; Jia ZHANG ; Fei LI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(2):207-217
ObjectiveTo investigate the therapeutic effects and mechanism of decoctions from four kinds of processed products of Aconiti Radix Lateralis Praeparata(ARLP) in deficiency-cold syndrome. MethodsA total of 36 SD rats were randomly divided into the control group, model group, Shengfupian(SFP) group, Paofuzi(PFZ) group, Heishunpian(HSP) group and Paofupian(PFP) group with 6 rats in each group. Except for the control group, rats in other groups were administered hydrocortisone sodium succinate via intramuscular injection to induce a cold deficiency syndrome model. After 14 consecutive days, each ARLP decoction pieces was administered via continuous gastric lavage at a dose of 12 g·kg-1·d-1 for 7 d, while the control and model groups received an equivalent volume of physiological saline. After the end of administration, body weight, spleen weight and thymus weight were measured for calculating the spleen and thymus indexes. Hematoxylin-eosin(HE) staining was used to observe the pathological morphology of adrenal tissue. The fully automatic biochemistry analyzer was used to measure the total cholesterol(TC), triglyceride(TG), lactic dehydrogenase(LDH) and lactate(LAC) levels in serum. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the contents of 17-hydroxycorticosteroid(17-OHCS), cortisol(CORT), triiodothyronine(T3), thyroxine(T4), thyrotropin(TSH), immunoglobulin(Ig) M, IgG, cyclic adenosine monophosphate(cAMP) and cyclic guanosine monophosphate(cGMP). Western blot was used to measure the protein expression levels of protein kinase A(PKA), cAMP response element-binding protein(CREB), silent information regulator 1(Sirt1) and peroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α). And high performance liquid chromatography(HPLC) was used to determine the content of major alkaloids, followed by Pearson correlation analysis with pharmacodynamic indicators. ResultsAfter modeling, compare with the control group, the model rats exhibited symptoms such as lethargy and loose stools, mild abnormalities were observed in adrenal tissue structure, and both spleen and thymus indices were significantly reduced(P<0.01). Thyroid, adrenal and immune system functions were suppressed, with decreased serum cAMP level and significantly elevated cGMP level(P<0.01). Compared with the model group, the adrenal injury by hydrocortisone sodium succinate were repaired and the spleen index were increased significantly in all four ARLP groups(P<0.05, P<0.01). The thymus index in SFP and PFZ groups were increased significantly(P<0.05). The contents of T3, TSH, 17-OHCS and CORT were increased significantly in SFP and PFZ groups(P<0.05). In addition, the content of IgG in SFP, PFZ and PFP groups were increased significantly(P<0.01), while the content of IgM in PFZ and HSP groups were also increased significantly(P<0.05). Regarding the cyclic nucleotide system, PFZ significantly elevated cAMP level while reducing cGMP level(P<0.05), exhibiting the most pronounced effect among the four decoction pieces. For energy metabolism indicators, PFZ significantly improved abnormal markers including TC, TG, LDH, and LAC(P<0.05). HSP showed marked improvement effects on TG, LDH, and LAC(P<0.05). Both PFZ and SFP significantly elevated the expression levels of PKA, CREB, Sirt1, and PGC-1α proteins(P<0.01). Additionally, the diester alkaloids in ARLP showed a strong positive correlation with TG, IgG, and CORT, a strong negative correlation with LAC, a moderate positive correlation with T4, and moderate negative correlations with cAMP and spleen index. Monomeric alkaloids showed strong positive correlations with TG and IgG, strong negative correlations with LAC, moderate positive correlations with CORT and T4, and moderate negative correlations with cAMP and spleen index. However, the content of water-soluble alkaloids showed strong positive correlations with TC, LDH, 17-OHCS, T3, TSH, and thymus index, moderate positive correlations with cAMP, CORT, T4, and spleen index, and moderate negative correlation with cGMP. ConclusionAmong different processed ARLP decoction pieces, PFZ processed according to ZHANG Zhongjing's method exhibits the most potent warming and cold-dispelling effects. Its pharmacological actions are mediated through regulating the thyroid, adrenal, immune, cyclic nucleotide systems, and material-energy metabolism pathways. Among these, water-soluble alkaloids show strong or moderate correlations with more indicators of deficiency-cold syndrome and exhibit the highest content in PFZ. Therefore, PFZ processed according to ZHANG Zhongjing's method may exert its warming and cold-dispelling effects through water-soluble alkaloids.
3.Comprehensive evaluation of powder-liquid double-chamber bag products: a systematic review
Fei SHU ; Rui SUN ; Kai SONG ; Yuanlin ZHANG ; Jiaming YAN ; Lixin SHU
Journal of Pharmaceutical Practice and Service 2025;43(2):92-96
Objective To evaluate the advantages of powder-liquid double-chamber bag products compared with traditional powder injection. Methods The systematic review method was used to collect the literature on powder-liquid double-chamber bag, extract common evaluation indicators, evaluate the use value of powder-liquid double-chamber bag products, and conduct a comprehensive comparison with traditional powder injection products. Results A total of 23 articles were included in the literature. The effectiveness indicators used for evaluation were the stability of the liquid medicine, the accuracy of the preparation concentration, and the residual amount of the liquid medicine; the safety indicators were the incidence of insoluble particles and the incidence of punctures and scratches. The economic indicators were preparation cost, occupied volume of preparation supplies, waste weight, hospitalization cost and incidence of blood infection. The applicability indicators were preparation time, average occupation of medical staff, packaging weight and storage and transportation volume, environmental adaptability, and ease of waste disposal. Accessibility indicators are the number of manufacturers, raw material supply capacity, and patient affordability. Through the evaluation of literature evidence, it was found that the stability and concentration accuracy of the powder-liquid double-chamber bag were higher than those of the traditional powder injection, and the domestic supply had been achieved. The double-chamber bag method can reduce the infusion reaction and shorten the preparation time of the liquid medicine. Conclusion Compared with traditional powder injectabler products, powder-liquid double-chamber bags have advantages in the dimensions of effectiveness, safety, economy, suitability and innovation, and the accessibility dimension meets the requirements.
4.Application of PLIBEL and REBA for identifying and assessing the risk of work-related musculoskeletal disorders among medical staff
Tongsu ZHANG ; Ruijie LING ; Jingzhi SUN ; Zhongxu WANG ; Ning JIA ; Chuansha WU ; Yan YANG ; Fei LIU ; Hong YIN
China Occupational Medicine 2025;52(6):618-623
Objective To identify potential ergonomic risk factors of works and quickly assess their risks of developing work-related musculoskeletal disorders (WMSDs) in the medical staff. Methods A total of 188 medical staff were selected as the research objects using a two-stage random sampling method. The method for the identification of musculoskeletal stress factors (PLIBEL) was used to analyze the adverse ergonomic factors in the work process, and the rapid entire body assessment (REBA) was used to quickly assess the whole-body posture load. Results The PLIBEL assessment results showed that various adverse ergonomic factors affected different parts of the body during the work process of medical staff. Specifically, 18 adverse ergonomic factors were identified in the neck, shoulders, and upper back, while 10 adverse ergonomic factors were identified in the elbow, forearm, hand, and lower back. Rehabilitation therapists and nurses engaged in patient handling in general wards and medication preparation and blood collection were exposed to ≥35 adverse ergonomic factors. The REBA assessment showed that the REBA score was 3-12 points for medical staff during their work process. Rehabilitation therapists were classified as having an extremely high ergonomic risk. High-risk occupations included ward housekeeping nurses, surgery assistant nurses, operating-room instrument nurses, and surgeons. Medium-risk occupations included general ward nurses (medication preparation and blood collection, venipuncture/infusion, and patient handling), intensive care unit (ICU) nurses, internal medicine residents, and dentists. Low-risk occupations included administrative front-desk nurses, outpatient internal medicine physicians, and technicians/physicians in ultrasonography, laboratory medicine, physical examination, and occupational health departments. Conclusion Adverse ergonomic factors of medical staff predominantly affect the neck, shoulders, upper back, elbows, forearms, hands, and the lower back during the work process. Rehabilitation therapists, ward housekeeping nurses, ICU nurses, operating-room instrument nurses, and surgeons are high-risk groups for WMSDs. Attention should be paid to the management and control of adverse ergonomic factors for medical staff to prevent the occurrence of WMSDs.
5.Icariside II attenuates isoproterenol-induced myocardial ischemia by regulating NLRP3/Caspase-1 axis
Wenzhong FENG ; Dong fei FANG ; Fangying TANG ; Jianmei GAO ; Fuchao CHEN ; Zhihao LI ; Cancan DUAN ; Yan ZHANG ; Ming YU ; Pingping WANG ; Jianyong ZHANG
Science of Traditional Chinese Medicine 2025;3(1):40-51
Background: Epimedii Folium, first recorded in the Shennong’s Classic of Materia Medica (Shen Nong Ben Cao Jing), is a traditional Chinese medicine (TCM) known for its effects of “benefiting Qi and strengthening the heart.” Icariside II (ICS II) is one of the main active components of Epimedii Folium, possessing cardiovascular protective and anti-inflammatory properties. However, the potential mechanisms of ICS II on myocardial ischemia (MI) remain unclear. Objective: The aim of the study was to investigate the effects and preliminary molecular mechanisms of ICS II in treating isoproterenolinduced MI in rats. Methods: A rat model of MI was established by subcutaneous injection of isoproterenol. Electrocardiography, echocardiography, myocardial enzymes analysis, heart weight index, triphenyltetrazolium chloride staining, histopathology, TUNEL staining, RT-qPCR, and Western blot were employed to evaluate the effects and preliminary molecular mechanisms of ICS II on MI rats. Results: Pharmacodynamic studies suggested that ICS II inhibited ST-segment elevation in electrocardiograms, improved cardiac function, reduced heart weight index and myocardial enzyme levels, decreased myocardial infarct size, alleviated cardiac histological damage, and inhibited apoptosis, thereby exerting cardioprotective effects in MI rats. Further studies revealed that ICS II may partially inhibit the expression of NLRP3/Caspase-1 axis-related targets at both protein and mRNA levels. Conclusions: Our findings indicate that ICS II exerts anti-MI effects, and its preliminary molecular mechanisms may be related to inhibiting the activation of the NLRP3/Caspase-1 axis to alleviate inflammatory responses.
6.Icariside II attenuates isoproterenol-induced myocardial ischemia by regulating NLRP3/Caspase-1 axis
Wenzhong FENG ; Dong fei FANG ; Fangying TANG ; Jianmei GAO ; Fuchao CHEN ; Zhihao LI ; Cancan DUAN ; Yan ZHANG ; Ming YU ; Pingping WANG ; Jianyong ZHANG
Science of Traditional Chinese Medicine 2025;3(1):40-51
Background: Epimedii Folium, first recorded in the Shennong’s Classic of Materia Medica (Shen Nong Ben Cao Jing), is a traditional Chinese medicine (TCM) known for its effects of “benefiting Qi and strengthening the heart.” Icariside II (ICS II) is one of the main active components of Epimedii Folium, possessing cardiovascular protective and anti-inflammatory properties. However, the potential mechanisms of ICS II on myocardial ischemia (MI) remain unclear. Objective: The aim of the study was to investigate the effects and preliminary molecular mechanisms of ICS II in treating isoproterenolinduced MI in rats. Methods: A rat model of MI was established by subcutaneous injection of isoproterenol. Electrocardiography, echocardiography, myocardial enzymes analysis, heart weight index, triphenyltetrazolium chloride staining, histopathology, TUNEL staining, RT-qPCR, and Western blot were employed to evaluate the effects and preliminary molecular mechanisms of ICS II on MI rats. Results: Pharmacodynamic studies suggested that ICS II inhibited ST-segment elevation in electrocardiograms, improved cardiac function, reduced heart weight index and myocardial enzyme levels, decreased myocardial infarct size, alleviated cardiac histological damage, and inhibited apoptosis, thereby exerting cardioprotective effects in MI rats. Further studies revealed that ICS II may partially inhibit the expression of NLRP3/Caspase-1 axis-related targets at both protein and mRNA levels. Conclusions: Our findings indicate that ICS II exerts anti-MI effects, and its preliminary molecular mechanisms may be related to inhibiting the activation of the NLRP3/Caspase-1 axis to alleviate inflammatory responses.
7.Icariside II attenuates isoproterenol-induced myocardial ischemia by regulating NLRP3/Caspase-1 axis
Wenzhong FENG ; Dong fei FANG ; Fangying TANG ; Jianmei GAO ; Fuchao CHEN ; Zhihao LI ; Cancan DUAN ; Yan ZHANG ; Ming YU ; Pingping WANG ; Jianyong ZHANG
Science of Traditional Chinese Medicine 2025;3(1):40-51
Background: Epimedii Folium, first recorded in the Shennong’s Classic of Materia Medica (Shen Nong Ben Cao Jing), is a traditional Chinese medicine (TCM) known for its effects of “benefiting Qi and strengthening the heart.” Icariside II (ICS II) is one of the main active components of Epimedii Folium, possessing cardiovascular protective and anti-inflammatory properties. However, the potential mechanisms of ICS II on myocardial ischemia (MI) remain unclear. Objective: The aim of the study was to investigate the effects and preliminary molecular mechanisms of ICS II in treating isoproterenolinduced MI in rats. Methods: A rat model of MI was established by subcutaneous injection of isoproterenol. Electrocardiography, echocardiography, myocardial enzymes analysis, heart weight index, triphenyltetrazolium chloride staining, histopathology, TUNEL staining, RT-qPCR, and Western blot were employed to evaluate the effects and preliminary molecular mechanisms of ICS II on MI rats. Results: Pharmacodynamic studies suggested that ICS II inhibited ST-segment elevation in electrocardiograms, improved cardiac function, reduced heart weight index and myocardial enzyme levels, decreased myocardial infarct size, alleviated cardiac histological damage, and inhibited apoptosis, thereby exerting cardioprotective effects in MI rats. Further studies revealed that ICS II may partially inhibit the expression of NLRP3/Caspase-1 axis-related targets at both protein and mRNA levels. Conclusions: Our findings indicate that ICS II exerts anti-MI effects, and its preliminary molecular mechanisms may be related to inhibiting the activation of the NLRP3/Caspase-1 axis to alleviate inflammatory responses.
8.Analysis of a child with Congenital leukemia and mosaicism trisomy 21 syndrome without GATA1 gene mutation.
Liya ZHANG ; Yu LIU ; Yu DING ; Lulu YAN ; Fei LI ; Qingqing JIE ; Shuni SUN ; Lili CHEN ; Xiamin JIN
Chinese Journal of Medical Genetics 2025;42(6):751-755
OBJECTIVE:
To explore the genetic characteristics and pathogenesis for a child with mosaicism trisomy 21 and Congenital leukemia (CL).
METHODS:
A child who was admitted to Ningbo Women and Children's Hospital in March 2023 was selected as the study subject. A retrospective analysis was carried out on the clinical data, laboratory test results, immunophenotyping, and genetic characteristics of the child. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: EC2024-063).
RESULTS:
Whole genome sequencing (WGS) revealed that the child has mosaicism trisomy of chromosome 21, with a ratio of approximately 74%. In addition, copy number variations involving multiple OMIM genes that could explain his clinical phenotype were detected and rated as pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). No pathogenic variant was detected with the GATA1 gene. Blood immune typing of the child conformed to the immunophenotype of acute myeloid leukemia.
CONCLUSION
For children with trisomy 21, even in the absence of GATA1 gene variants, the occurrence of CL should be monitored, and early diagnosis and treatment are of great significance for improving the prognosis.
Child, Preschool
;
Humans
;
DNA Copy Number Variations/genetics*
;
Down Syndrome/genetics*
;
GATA1 Transcription Factor/genetics*
;
Leukemia/congenital*
;
Mosaicism
;
Mutation
;
Retrospective Studies
;
Whole Genome Sequencing
9.Clinical features of traumatic optic neuropathy in 323 cases
Ziyi ZHANG ; Yan JIANG ; Min CHEN ; Fei CHE ; Junfeng WEN ; Na LI ; Jianbao JU
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2025;60(10):1284-1290
Objective:To analyze the clinical features of patients with traumatic optic neuropathy (TON) and to explore its clinical patterns and treatment outcomes.Methods:A retrospective analysis was conducted on data from 323 patients (334 eyes) with TON, who were treated in the Department of Otorhinolaryngology Head and Neck Surgery, the Affiliated Hospital of Qingdao University from April 1999 to October 2024. Among these patients, 288 were male and 35 were female, with ages ranging from 4 to 70 years. All patients were followed up for a period of 6 to 24 months, with the final follow-up visual acuity recorded as the ultimate visual outcome. The visual acuity evaluation criteria were classified into five levels: no light perception, light perception, hand movement in front of the eye, counting fingers at 1 meter, and "chart-visible acuity". A treatment outcome was deemed effective if the post-treatment visual acuity improved by one level or more compared to pre-treatment, or if the chart-visible acuity improved by two lines or more on the logMAR chart. The clinical characteristics of patients, causes of injury, complications, treatment methods, and changes in visual acuity before and after treatment were summarized. Logistic regression analyses were performed to identify the influencing factors affecting treatment efficacy.Results:TON occurred mostly in young (215/323, 66.56%) males (288/323, 89.16%), the majority of patients came from villages and towns (236/323, 73.07%). Traffic accidents (232/323, 71.83%) remained the main etiology. Most patients had craniofacial injuries and other bodily injuries. The effective rate of vision improvement was 50.30% (168/334). Multiple logistic regression analyses identified that residual vision (light perception or better) at presentation ( OR=3.26, P<0.001) and receiving treatment within 7 days after injury ( OR=2.04, P=0.008) were protective factors on visual acuity recovery, while the presence of orbital wall fracture was a risk factor for visual acuity recovery ( OR=0.26, P<0.001). Additionally, undergoing surgical treatment was a protective factor for visual improvement in patients with no light perception ( OR=2.94, P=0.007). For patients with residual vision at presentation, orbital wall fracture was a significant risk factor ( OR=0.28, P=0.009). Conclusions:TON is more prevalent in young males and is primarily caused by traffic accidents, leading to a poor prognosis. Timely medical intervention following injury significantly influences prognostic outcomes. Early surgical intervention (within 7 days) is recommended, particularly for patients with no light perception at presentation.
10.Guidelines for the Digital Ancient Books of TCM Indexing
Weina ZHANG ; Bing LI ; Bin LI ; Jing XIE ; Yan DONG ; Wei LONG ; Chuchu ZHANG ; Tong WEI ; Sihong LIU ; Yang WU ; Hongtao LI ; Lin TONG ; Guangkun CHEN ; Fei DONG ; Rui WANG ; He LU ; Meng LI ; Jingpeng DENG ; Tengfei WANG ; Xiaoying LI ; Di ZHANG
Chinese Journal of Information on Traditional Chinese Medicine 2025;32(3):1-11
Guidelines for Digital Ancient Books of TCM Indexing(T/CIATCM 119-2024)is based on the theoretical knowledge,disciplinary methods,and practical applications of TCM classical cataloging.Taking digital ancient books of TCM as the object,it systematically reveals the content of TCM knowledge,which is an essential indexing processing standard for building an intelligent retrieval system for TCM ancient books,and can provide support for the deep development and innovative utilization of TCM knowledge.It can not only promote the co-construction and sharing of ancient book resources in the TCM industry,but also promote the standardization construction and application of TCM information.This standard specifies the principles,methods,and examples of free indexing of digital ancient books of TCM based on their original content.It is applicable to the indexing and processing of digital ancient books of TCM for TCM professional libraries and related institutions,and to the data processing and construction of various types of TCM ancient book databases.

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