1.Olfactory Receptors Expressed in The Intestine and Their Functions
Pei-Wen YANG ; Meng-Meng YUAN ; Ying ZHOU ; Peng LI ; Gui-Hong QI ; Ying YANG ; Zhong-Yi MAO ; Meng-Sha ZHOU ; Xiao-Shuang MAO ; Jian-Ping XIE ; Yi-Nan YANG ; Shi-Hao SUN
Progress in Biochemistry and Biophysics 2026;53(3):534-549
Olfactory receptors (ORs) form the largest superfamily of G protein-coupled receptors (GPCRs). Traditionally recognized for their role in the nasal olfactory epithelium, where they mediate the sense of smell, accumulating evidence has firmly established their ectopic expression in non-olfactory tissues, including the intestine, lungs, and kidneys. The intestine, as the primary site for nutrient digestion and absorption, harbors a highly complex chemical environment. To adapt to this environment, the gut employs a sophisticated network of “chemosensors” to monitor luminal contents and maintain homeostasis. Among these sensors, intestinal ORs have emerged as crucial functional components, serving as a molecular bridge that connects environmental chemical signals—such as food-derived odorants—to specific physiological responses. This discovery has significantly deepened our understanding of how dietary flavors and compounds influence intestinal physiology at the molecular level. This review systematically summarizes the expression profiles, ligand classification, and biological functions of ORs within the gastrointestinal tract. Studies indicate that intestinal ORs exhibit distinct spatial distribution patterns across different gut segments and display cell-type specificity, particularly within enterocytes and enteroendocrine cells. These receptors function as versatile sensors capable of recognizing a wide variety of ligands, including exogenous dietary components, gut microbiota metabolites such as short-chain fatty acids, and endogenous small molecules like azelaic acid. Upon activation by specific ligands, intestinal ORs trigger intracellular signaling cascades, primarily involving the AC-cAMP-PKA pathway or calcium influx channels. A major focus of this review is to elucidate the molecular mechanisms by which these receptors regulate the secretion of gut hormones. Activation of specific ORs in enteroendocrine cells has been shown to stimulate the release of hormones such as glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and serotonin (5-HT), thereby modulating systemic energy metabolism, glucose homeostasis, and gastrointestinal motility. Furthermore, the review addresses the critical roles of ORs in immune regulation and pathology. Evidence suggests that specific ORs contribute to the maintenance of intestinal immune homeostasis and may offer protection against inflammation. Beyond their involvement in inflammatory responses, ORs such as Olfr78 have been shown to regulate the differentiation and function of intestinal endocrine cells. Similarly, Olfr544 has been demonstrated to alleviate intestinal inflammation by remodeling the gut microbiome and metabolome. These findings collectively suggest that specific ORs hold promise as therapeutic targets for mitigating intestinal inflammation and maintaining gut homeostasis. Additionally, the review explores the emerging role of ORs in cancer. Although OR expression is often downregulated in tumor tissues compared to normal mucosa, activation of specific ORs by certain ligands can inhibit tumor cell proliferation and migration and induce apoptosis via pathways such as MEK/ERK and p38 MAPK. Conversely, other receptors, such as OR7C1, may serve as biomarkers for cancer-initiating cells. In conclusion, intestinal ORs represent a vital component of the gut’s sensory network. The review also discusses the translational potential of these findings. By elucidating the precise pairing relationships between dietary components and specific ORs, novel therapeutic strategies could be developed. Intestinal ORs may thus emerge as promising targets for nutritional and pharmacological interventions in metabolic diseases, inflammatory bowel diseases, and malignancies.
2.Polydatin Delays Progression of Colitis-associated Colorectal Cancer by Modulating IL-17A/Wnt/β-catenin Signaling Pathway
Jie LIU ; Mengmeng LYU ; Yanfei HONG ; Xinmei NAN ; Jialong SU ; Huachen LIU ; Qing WANG ; Guiying PENG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(13):144-154
ObjectiveTo investigate the effects and underlying mechanisms of polydatin in delaying the progression of colitis-associated colorectal cancer (CAC) by constructing an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CAC mouse model and conducting in vitro experiments. MethodsFifty-four male C57BL/6J mice were randomly divided into normal, model, and polydatin groups (0.045 g·kg-1). The CAC mouse model was established using AOM/DSS, and samples were collected at 4, 7, and 10 weeks. Body weight change rate, disease activity index (DAI), and tumor formation were assessed. Hematoxylin-eosin (HE) staining was used to observe pathological injury in intestinal tissues. Immunohistochemistry (IHC) was performed to detect zonula occludens-1 (ZO-1) expression in colonic tissues, and Western blot was used to detect the expression of E-cadherin, N-cadherin, and Vimentin in colonic epithelial cells. Real-time PCR was used to measure mRNA expression of interleukin-17A (IL-17A), Wnt3a, β-catenin, T cell factor 1 (Tcf1), E-cadherin, N-cadherin, and Vimentin in colonic tissues. Flow cytometry was used to analyze the proportion of CD8+T cells and the expression of exhaustion-related molecules in tumors. Human colon cancer DLD-1 cells were cultured in a polydatin-containing medium, and wound healing assays were performed to observe migration changes. Real-time PCR was used to detect mRNA expression of interleukin-17 receptor A (IL-17RA), Wnt3a, β-catenin, Tcf1, E-cadherin, N-cadherin, and Vimentin in DLD-1 cells. ResultsCompared with the normal group, the model group at all three time points showed significantly decreased body weight change rate (P<0.01), significantly shortened colon length (P<0.01), and markedly increased DAI scores (P<0.01). HE staining revealed significant inflammatory cell infiltration in the submucosa of the colon in the model group, accompanied by epithelial dysplasia. ZO-1 expression in colonic tissues was significantly reduced (P<0.01). The mRNA expression of the pro-inflammatory factor IL-17A and key molecules of the Wnt/β-catenin pathway (Wnt3a, β-catenin, Tcf1) was significantly elevated (P<0.05). The mRNA and protein expression of epithelial-mesenchymal transition (EMT) markers N-cadherin and Vimentin was significantly upregulated (P<0.05), while E-cadherin expression was significantly downregulated (P<0.05). The proportion of tumor-infiltrating CD8+T cells expressing immunosuppressive molecules (TIM-3, LAG-3, PD-1) was significantly increased (P<0.05). Compared with the model group, the polydatin group showed significant improvement in body weight and DAI score (P<0.01), as well as recovery of colon length and tissue injury. ZO-1 expression in colonic tissue was significantly increased (P<0.01), while IL-17A, Wnt3a, β-catenin, Tcf1, N-cadherin, and Vimentin expression levels were significantly decreased (P<0.05), and E-cadherin expression was significantly increased (P<0.01). Tumor-infiltrating CD8+ T cells expressing immunosuppressive molecules were significantly reduced (P<0.05). In vitro experiments showed that polydatin significantly inhibited migration of DLD-1 cells (P<0.01) and reversed the upregulation of IL-17RA, Wnt3a, β-catenin, N-cadherin, and Vimentin mRNA, as well as the downregulation of E-cadherin mRNA (P<0.05). ConclusionPolydatin inhibits IL-17A secretion and IL-17RA expression, improves the immune microenvironment, blocks activation of the Wnt/β-catenin signaling pathway, suppresses EMT markers (N-cadherin and Vimentin), and restores tight junction protein expression in intestinal epithelial cells, thereby delaying the progression from colitis to colorectal cancer in mice.
3.Molecular Mechanism of Gypenoside L Inducing Ovarian Cancer Cell Apoptosis by Regulating NUF2 and Influencing Magnesium Homeostasis
Yang HONG ; Di ZHANG ; Yuanguang DONG ; Jiaxin WANG ; Lu PAN ; Lijiang ZHOU ; Mingdian YUAN ; Qun WANG ; Nan SONG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(13):155-165
ObjectiveThis paper aims to investigate the role of NDC80 kinetochore complex component (NUF2) and magnesium homeostasis in ovarian cancer cell apoptosis, as well as the regulatory mechanism of gypenoside L (Gyp-L) on NUF2 and magnesium homeostasis. MethodsOvarian cancer OVCAR3 cells were divided into a blank control group, a low-concentration Gyp-L group (50 µmol·L-1), a high-concentration Gyp-L group (100 µmol·L-1), and a cisplatin (15 µmol·L-1) group. The migration, proliferation, and apoptosis capabilities of OVCAR3 cells were evaluated through cell scratch assays, clonal experiments, and terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) staining. Differentially expressed genes of ovarian cancer were screened by using the Gene Expression Omnibus (GEO) database. The interaction relationships of differentially expressed genes and proteins were analyzed via the Search Tool for Recurring Instances of Neighbouring Genes (STRING) database. The prognostic survival analysis was performed by using the Tumor Immune Estimation Resource (TIMER) database, and the differential expression levels of genes were validated with the Gene Expression Profiling Interactive Analysis (GEPIA) database. The mRNA expression levels of NUF2, magnesium homeostasis-related indicators, such as magnesium transporter 1 (MAGT1), non-imprinted in Prader-Willi/Angelman syndrome 1 (NIPA1), NIPA-like domain containing 1 (NIPAL1), as well as apoptosis-related indicators B cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) in OVCAR3 cells, were detected by real-time quantitative polymerase chain reaction (Real-time PCR). The protein expression levels of NUF2, MAGT1, NIPA1, NIPAL1, Bcl-2, and Bax in OVCAR3 cells were quantitatively analyzed by ProteinSimple WES. A model of overexpression of NUF2 was constructed, and Gyp-L intervention was performed. The molecular mechanism by which Gyp-L induces ovarian cancer cell apoptosis by regulating NUF2 and influencing magnesium homeostasis was quantitatively analyzed and detected through cell cloning, TUNEL staining, Real-time PCR, and ProteinSimple WES. Finally, the Mg2+ content and protein synthesis efficiency were detected by immunofluorescence. ResultsGyp-L significantly inhibited the migration and proliferation capabilities of OVCAR3 cells and promoted their apoptosis (P<0.05). Overexpression of NUF2 markedly increased the expression levels of MAGT1, NIPA1, NIPAL1, and Bcl-2, while reducing the expression level of Bax (P<0.05). It also significantly elevated intracellular Mg2+ content and protein synthesis efficiency and simultaneously inhibited apoptosis (P<0.05). Gyp-L could reverse the magnesium homeostasis imbalance and apoptosis inhibition caused by the overexpression of NUF2, downregulating the expression levels of NUF2, MAGT1, NIPA1, NIPAL1, and Bcl-2 (P<0.05), while upregulating the expression level of Bax (P<0.05). ConclusionGyp-L can inhibit the occurrence of ovarian cancer, and its mechanism may involve inhibiting the expression of NUF2 to maintain magnesium homeostasis and inducing apoptosis of ovarian cancer cells.
4.Construction Strategies and Challenges of Vascularized Brain Organoids
Meng-Meng CHEN ; Nan HU ; Shuang-Qing BAO ; Xiao-Hong LI
Progress in Biochemistry and Biophysics 2025;52(7):1757-1770
Brain organoids are three-dimensional (3D) neural cultures that self-organize from pluripotent stem cells (PSCs) cultured in vitro. Compared with traditional two-dimensional (2D) neural cell culture systems, brain organoids demonstrate a significantly enhanced capacity to faithfully replicate key aspects of the human brain, including cellular diversity, 3D tissue architecture, and functional neural network activity. Importantly, they also overcome the inherent limitations of animal models, which often differ from human biology in terms of genetic background and brain structure. Owing to these advantages, brain organoids have emerged as a powerful tool for recapitulating human-specific developmental processes, disease mechanisms, and pharmacological responses, thereby providing an indispensable model for advancing our understanding of human brain development and neurological disorders. Despite their considerable potential, conventional brain organoids face a critical limitation: the absence of a functional vascular system. This deficiency results in inadequate oxygen and nutrient delivery to the core regions of the organoid, ultimately constraining long-term viability and functional maturation. Moreover, the lack of early neurovascular interactions prevents these models from fully recapitulating the human brain microenvironment. In recent years, the introduction of vascularization strategies has significantly enhanced the physiological relevance of brain organoid models. Researchers have successfully developed various vascularized brain organoid models through multiple innovative approaches. Biological methods, for example, involve co-culturing brain organoids with endothelial cells to induce the formation of static vascular networks. Alternatively, co-differentiation strategies direct both mesodermal and ectodermal lineages to generate vascularized tissues, while fusion techniques combine pre-formed vascular organoids with brain organoids. Beyond biological approaches, tissue engineering techniques have played a pivotal role in promoting vascularization. Microfluidic systems enable the creation of dynamic, perfusable vascular networks that mimic blood flow, while 3D printing technologies allow for the precise fabrication of artificial vascular scaffolds tailored to the organoid’s architecture. Additionally, in vivo transplantation strategies facilitate the formation of functional, blood-perfused vascular networks through host-derived vascular infiltration. The incorporation of vascularization has yielded multiple benefits for brain organoid models. It alleviates hypoxia within the organoid core, thereby improving cell survival and supporting long-term culture and maturation. Furthermore, vascularized organoids recapitulate critical features of the neurovascular unit, including the early structural and functional characteristics of the blood-brain barrier. These advancements have established vascularized brain organoids as a highly relevant platform for studying neurovascular disorders, drug screening, and other applications. However, achieving sustained, long-term functional perfusion while preserving vascular structural integrity and promoting vascular maturation remains a major challenge in the field. In this review, we systematically outline the key stages of human neurovascular development and provide a comprehensive analysis of the various strategies employed to construct vascularized brain organoids. We further present a detailed comparative assessment of different vascularization techniques, highlighting their respective strengths and limitations. Additionally, we summarize the principal challenges currently faced in brain organoid vascularization and discuss the specific technical obstacles that persist. Finally, in the outlook section, we elaborate on the promising applications of vascularized brain organoids in disease modeling and drug testing, address the main controversies and unresolved questions in the field, and propose potential directions for future research.
5.The protective effect of Gualou Guizhi granules on neuronal injury induced by LPS-activated microglia based on Notch signaling pathway
Xue-zhen LI ; Xiao-xue ZOU ; Wen-ting CHEN ; Yi FENG ; Ya-nan LI ; Yu-qin ZHANG ; Li-hong NAN
Chinese Pharmacological Bulletin 2025;41(4):781-786
Aim To investigate the protective effect of Gualou Guizhi granules(GLGZG)on neuronal injury induced by LPS-activated microglia based on Notch signaling pathway.Methods LPS-activated microglia were co-cultured with neurons to construct neuron inju-ry models,and the cells were divided into the control group,model group,Notch inhibitor(DAPT)group,GLGZG(50,100,200 mg·L-1)group,DAPT+100 mg·L-1GLGZG group.After intervention,the activity of HT22 cells was detected by CCK-8 method,and rel-ative mRNA expression was detected by real-time PCR.The relative protein expression was detected by Western blot.Results Compared with the model group,after GLGZG intervention,the cell activity was significantly improved,GLGZG decreased IL-6,IL-12,Bax,Notch 1,caspase-3,Delta-1,NICD,RBPSUH,HES1 expression,and increased Bcl-2 expression(P<0.05).Compared with the model group,the NICD,RBPSUH and HES1 mRNA and protein expressions significantly decreased after DAPT treatment(P<0.05),and there was no superposition effect with GLG-ZG.Conclusion GLGZG may play a neuroprotective role by inhibiting inflammatory factors and apoptosis,and inhibiting Notch signaling pathway.
6.Non-contrast CT radiomics for predicting recurrence of acute pancreatitis
Bingbing LIN ; Ping YIN ; Fei ZHENG ; Nan HONG
Chinese Journal of Medical Imaging Technology 2025;41(5):749-752
Objective To observe the value of non-contrast CT radiomics for predicting recurrence of acute pancreatitis(AP).Methods Totally 356 patients with first-episode AP were retrospectively enrolled.The patients were categorized into recurrence group(n=78)and non-recurrence group(n=278)based on whether recurrence after 3 months of complete/near disappearance of symptoms,also divided into training set(n=213)and test set(n=143)at the ratio of 6∶4.For 116 cases who underwent contrast-enhanced CT,taken portal venous phase images as references,ROI of pancreatic parenchyma was manually delineated on non-contrast CT,while SegResNet segmentation model was used for automatic segmentation on non-contrast CT images for the rest 240 cases.The optimal radiomics features were extracted and selected to construct a radiomics model based on YeoJohnson transformer and Bagging decision tree.The receiver operating characteristic curve was drawn,and the area under the curve(AUC)was calculated to evaluate the efficacy of the obtained model for predicting AP recurrence.Results Totally 2 264 radiomics features were extracted from ROI of pancreatic parenchyma,and finally 4 optimal features were screened.The AUC of radiomics model for predicting recurrence was 0.887 and 0.889 in training set and test set,respectively.Conclusion Non-contrast CT radiomics could be used to effectively predict recurrence of AP.
7.Underlying target of bullatine A in treating rheumatoid arthritis based on LiP-SMap drug target proteomics
Hao-hong ZHANG ; Nan-ting ZOU ; Chun-fei ZHANG ; Qing-yan MO ; Ming-qian JU ; Xiao-hong LI ; Shuai LIU ; Mao-kui HUANG ; Hong-yun WANG ; Chun-ping WAN
Chinese Pharmacological Bulletin 2025;41(6):1072-1078
Aim To identify the underlying target of bullatine A(BA)against rheumatoid arthritis(RA)u-sing limited proteolysis-small molecule mapping(LiP-SMap)drug target proteomics and to provide a scientif-ic basis for clinical application of Aconiti brachypodi Radix in the treatment of RA.Methods LiP-SMap drug target proteomics was employed to perform bioin-formatics analysis for comparing and validating the dif-ferential protein expression after BA intervention.A collagen-induced arthritis(CIA)model was estab-lished in DBA/1 mice using bovine type Ⅱ collagen.The mice were then divided into the CIA model group,methotrexate-positive control group(MTX group),and BA groups(10 mg·kg-1 and 20 mg·kg-1)based on their clinical scores.After drug intervention,the thera-peutic efficacy against RA was assessed by joint index scores and foot thickness measurements.Histopatholog-ical changes in the arthritic joints of CIA mice were e-valuated using hematoxylin and eosin(HE)staining.Enzyme-linked immunosorbent assay(ELISA)was employed to detect inflammatory cytokines interleukin-17(IL-17)and total IgG and IgG3 anti-collagen-spe-cific antibodies levels from the serum of CIA mice.Flow cytometry was used to detect the expression levels of intracellular Th17 cells(IL-17+CD4+T cells)and Th1 cells(IFN-γ+CD4+T cells).Fluorescent quanti-tative PCR was performed to detect the expression of genes related to differential proteins.Results The proteomic analysis identified Serpinb1a as a protein with strong binding affinity to BA,and KEGG enrich-ment analysis indicated IL-17 signaling pathway was a crucial pathway of BA in against RA.BA treatment significantly reduced clinical scores and foot thickness,improved local arthritis symptoms in CIA mice,and al-leviated inflammatory cell infiltration into arthritic joints(P<0.05).Differential protein validation re-sults showed that BA had strong affinity with Serpinb1a(-5.92 kJ·mol-1)and downregulated the expres-sion of Serpinb1a mRNA.Furthermore,the administra-tion of BA markedly reduced serum IL-17 A levels from CIA mice,inhibited the expression of intracellular IL-17 A and IFN-γ cytokines in splenic CD4+T cells(P<0.05),and significantly downregulated the transcrip-tional expression of IL-17F(P<0.05).Conclusion BA exhibits therapeutic effects on collagen-induced arthritis,and its mechanism of action may involve the regulation of Serpinb1a and the IL-17 signaling path-way.
8.Research progress in laboratory artificial breeding technologies for ticks
Xiao-nan DONG ; Lian-yang SUN ; Hao CUI ; Jia-mei KANG ; Yu-lin DING ; Yong-hong LIU ; Li ZHAO
Chinese Journal of Zoonoses 2025;41(1):67-74
As the world's second largest vector of pathogens,ticks can spread a variety of pathogens by sucking the host's blood.Ticks not only threaten human life and health,but also cause great economic losses in animal husbandry.Artificial breeding of ticks can provide a stable environment for the growth and reproduction of ticks,thereby generating sufficient exper-imental materials for understanding ticks'biological characteristics,studying tick-borne pathogens,and developing anti-tick drugs and vaccines.Current methods of breeding ticks in the laboratory can be roughly divided into two categories:breeding methods using host animals or artificial membranes.The selection of breeding method must be comprehensively considered,ac-cording to tick types,blood-sucking habits,living environments,and other aspects.The development processes of the two methods,and their respective advantages and disadvantages,are described and discussed,to assist laboratories in artificial breeding of ticks.
9.Study on the Relationship between Serum PGRN,PTX3,KL-6 and the Prognosis of Patients with AECOPD Combined with Type Ⅱ Respiratory Failure after Nasal High-Flow Humidified Oxygen Therapy
Ben LIU ; Xian-hong LIU ; Nan ZHANG
Progress in Modern Biomedicine 2025;25(18):3003-3009,2948
Objective:To investigate the relationship between serum progranulin(PGRN),pentraxin 3(PTX3),krebs von den lungen-6(KL-6)and the prognosis of patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD)combined with type Ⅱ respiratory failure(RF)after nasal high-flow humidified oxygen therapy.Methods:160 patients with AECOPD combined with type Ⅱ RF who were treated in Zigong First People's Hospital from June 2022 to June 2024 were retrospectively selected,all patients received nasal high-flow humidified oxygen therapy,and they were divided into death group(38 cases)and survival group(122 cases)according to the prognosis of patients after treatment.The differences of serum PGRN,PTX3 and KL-6 levels and clinical data between two groups before treatment were compared.Logistic regression was applied to analyze the influencing factors of the poor prognosis of patients,and the receiver operating characteristic(ROC)curve was used to analyze the predictive efficacy of related risk factors for the poor prognosis of patients.Results:According to the prognosis evaluation,122 cases(76.25%)were in survival group,and 38 cases(23.75%)were in death group.Compared with survival group,serum PGRN,PTX3,KL-6,C-reactive protein(CRP),arterial partial pressure of carbon dioxide(PaCO2)and the number of AECOPD episodes in the past 1 year before treatment in death group were significantly increased,while the arterial partial pressure of oxygen(PaO2)was significantly decreased,the differences were statistically significant(P<0.05).Logistic multivariate regression analysis showed that,elevated PGRN(OR=1.138),elevated PTX3(OR=1.182)and elevated KL-6(OR=1.162)were risk factors for death in patients with AECOPD combined with type Ⅱ RF after nasal high-flow humidified oxygen therapy(P<0.05),and elevated PaO2(OR=0.758)was protective factor(P<0.05).ROC curve analysis showed that the area under the curve(AUC)of serum PGRN,PTX3 and KL-6 in predicting the death of patients with AECOPD combined with type Ⅱ RF after nasal high-flow humidified oxygen therapy was 0.816,0.731 and 0.695 respectively,the AUC of the combined prediction of the three was 0.893,which was significantly higher than that of the single prediction.Conclusion:The levels of serum PGRN,PTX3 and KL-6 in patients with AECOPD combined with type Ⅱ RF are increased,which have high predictive value for the poor prognosis of patients with AECOPD combined with type Ⅱ RF after nasal high-flow humidified oxygen therapy.
10.Review of application scope of mobile medical devices combined with EMA method for lung cancer patient caring
Zi-dan WANG ; Hong-yue WU ; Bing LI ; Xin-tong ZHENG ; Jun-ling LIU ; Ying-nan ZHAO ; Yan LI
Chinese Medical Equipment Journal 2025;46(10):71-77
Relevant literature on mobile medical devices combined with the ecological momentary assessment(EMA)method applied to lung cancer patient caring was collected from some databases of CNKI,Wanfang,VIP,China Biomedical Literature Database,PubMed,Embase,Cochrane Library,CINAHL and Web of Science.The method of scoping review was used to sort out the general characteristics of the included literature,types and application of mobile medical devices,assessment content elements and outcome indicators.The feasibility and validity of mobile medical devices combined with the EMA method for the symptom assessment of lung cancer patients were described,whose advantages in monitoring during lung cancer caring and application prospects were elaborated.The problems of mobile medical devices during practical application were pointed out and some countermeasures were put forward accordingly.References were provided for personalized remote caring of lung cancer patients and development of intelligent multi-modal mobile devices.[Chinese Medical Equipment Journal,2025,46(10):71-77]

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