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.Expert consensus on precise intervention with repetitive transcranial magnetic stimulation for sleep disorders in the elderly
Yuan SHAO ; Jian WANG ; Wei LIANG ; Yingli ZHANG ; Gangqiang HOU ; Xia LI ; Yi XING ; Lu WANG ; Shi TANG ; Yongjun WANG
Sichuan Mental Health 2026;39(2):97-105
In recent years, repetitive transcranial magnetic stimulation (rTMS) has garnered significant attention as a therapeutic approach for sleep disorders in the elderly. However, the prevailing rTMS protocols are predominantly developed based on normative neurophysiological data derived from young adults and fail to incorporate individualized parameters tailored to the brain characteristics of the elderly. To address this gap, the consensus development group synthesized the latest evidence from 2010 to 2025 and established a standardized rTMS protocol specifically for elderly patients with sleep disorders. Adhering to the Appraisal of Guidelines for Research and Evaluation II (AGREE II) framework, systematically screened randomized controlled trials (RCTs) and systematic reviews regarding rTMS in the treatment of sleep disorders across various conditions. Meanwhile, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was employed to rigorously grade the quality of evidence and the strength of recommendations. This consensus guideline delineates precise rTMS protocols for the management of sleep disorders in the elderly, highlights the adjustment of stimulation intensity according to scalp-cortex distance recommends either MRI‑guided neuronavigation or the Beam F3/F4 heuristic approach for accurate target localization, thereby providing precise rTMS intervention protocol for sleep disorders in the elderly, aiming to enhance clinical efficacy while ensuring treatment safety. [Funded by National Key Research and Development Program (number, 2023YFC3603200); General Program of Shenzhen Science and Technology Innovation Commission (number, JCYJ20240813112859008, JCYJ20240813112900002); Youth Program of Shenzhen Kangning Hospital (number, KN2023A004); www.guidelines-registry.cn number, PREPARE-2026CN530]
3.Electroacupuncture Ameliorates NLRP3-mediated Pyroptosis in Spinal Cord Injury Rats by Reshaping The Gut Microbiota
Yin-Jie CUI ; Hong-Ru LI ; Jing-Yi LIU ; Hai-Lin DU ; Shu-Wen LIU ; Yuan YANG ; Chen-Guang ZHENG ; Jian-Qin XIANG ; Xiao-Juan SONG
Progress in Biochemistry and Biophysics 2026;53(5):1132-1153
ObjectiveSpinal cord injury (SCI) directly impairs the regulatory function of the autonomic nervous system, induces intestinal dysfunction, and significantly reduces patients’ quality of life. Preclinical studies have shown that electroacupuncture (EA) therapy can regulate the brain-gut axis and is used to treat central nervous system diseases such as major depressive disorder, Alzheimer’s disease and Parkinson’s disease. Recent research has established that fecal microbiota transplantation (FMT) from EA-treated SCI rats restored intestinal motility and colonic morphology. However, it remains unclear whether the regulation of gut microbiota by EA therapy directly contributes to neural repair after SCI. This study aims to explore whether gut microbiota mediates the neuroprotective effect of EA in the treatment of SCI and its possible mechanism. MethodsThe study employed RNA transcriptome analysis of spinal cord tissue to characterize gene expression profiles and to identify key signaling pathways following EA treatment for SCI. Hematoxylin-Eosin (HE) staining and Nissl staining were used to observe the morphological changes in spinal cord tissue. Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) were applied to detect the effects of EA on the expression of proteins related to nucleotide-binding domain leucine-rich repeat and pyrin domain-containing receptor 3 (NLRP3) -dependent pyroptosis. Using 16S rDNA sequencing, the study observed alterations in gut microbiota diversity and community composition in SCI rats. Prior to establishing SCI models, rats were pretreated with an antibiotic cocktail to induce gut dysbiosis, and the effects on intestinal function and spinal cord neural repair were evaluated. FMT was performed to investigate the regulatory effects of post-EA FMT on motor function, general status, liver and spleen indices, and NLRP3-mediated pyroptosis in SCI rats. ResultsEA improved motor function and reduced regulated neuronal cell death in SCI rats. Transcriptomic analysis demonstrated the activation of immune- and inflammation-related pathways post-SCI, including NOD-like receptors, nuclear factor-kappa B(NF-κB), and Toll-like receptor (TLR) pathways. EA primarily influenced intestinal inflammation and autoimmune functions. 16S rDNA sequencing illustrated that EA did not alter the diversity of gut microbiota. However, EA altered the gut microbiota composition in SCI rats, increasing Lactobacillus and Akkermansia genera while rebalancing the Firmicutes/Bacteroidetes ratio. Furthermore, depletion of gut microbiota by antibiotics disrupted the intestinal barrier, reduced the expression of intestinal barrier proteins Zonula Occludens-1 (ZO-1) and Occludin, elevated serum lipopolysaccharide-binding protein (LBP) levels, exacerbated spinal cord tissue damage, and hindered motor function recovery in SCI rats. FMT from donors treated with EA reduced LBP levels in the intestine, blood, and spinal cord of rats, inhibited the TLR4 myeloid differentiation primary response protein 88 (MyD88)-NF‑κB pathway and NLRP3-dependent pyroptosis, and improved motor function. On the other hand, FMT treatment resulted in decreased body weight and food intake, whereas FMT using EA-treated donors effectively alleviated these alterations. ConclusionEA effectively alleviated neuroinflammatory responses in rats with SCI, primarily through regulating the gut microbiota and suppressing the NLRP3-dependent pyroptosis signaling pathway.
4.Electroacupuncture Ameliorates NLRP3-mediated Pyroptosis in Spinal Cord Injury Rats by Reshaping The Gut Microbiota
Yin-Jie CUI ; Hong-Ru LI ; Jing-Yi LIU ; Hai-Lin DU ; Shu-Wen LIU ; Yuan YANG ; Chen-Guang ZHENG ; Jian-Qin XIANG ; Xiao-Juan SONG
Progress in Biochemistry and Biophysics 2026;53(5):1132-1153
ObjectiveSpinal cord injury (SCI) directly impairs the regulatory function of the autonomic nervous system, induces intestinal dysfunction, and significantly reduces patients’ quality of life. Preclinical studies have shown that electroacupuncture (EA) therapy can regulate the brain-gut axis and is used to treat central nervous system diseases such as major depressive disorder, Alzheimer’s disease and Parkinson’s disease. Recent research has established that fecal microbiota transplantation (FMT) from EA-treated SCI rats restored intestinal motility and colonic morphology. However, it remains unclear whether the regulation of gut microbiota by EA therapy directly contributes to neural repair after SCI. This study aims to explore whether gut microbiota mediates the neuroprotective effect of EA in the treatment of SCI and its possible mechanism. MethodsThe study employed RNA transcriptome analysis of spinal cord tissue to characterize gene expression profiles and to identify key signaling pathways following EA treatment for SCI. Hematoxylin-Eosin (HE) staining and Nissl staining were used to observe the morphological changes in spinal cord tissue. Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) were applied to detect the effects of EA on the expression of proteins related to nucleotide-binding domain leucine-rich repeat and pyrin domain-containing receptor 3 (NLRP3) -dependent pyroptosis. Using 16S rDNA sequencing, the study observed alterations in gut microbiota diversity and community composition in SCI rats. Prior to establishing SCI models, rats were pretreated with an antibiotic cocktail to induce gut dysbiosis, and the effects on intestinal function and spinal cord neural repair were evaluated. FMT was performed to investigate the regulatory effects of post-EA FMT on motor function, general status, liver and spleen indices, and NLRP3-mediated pyroptosis in SCI rats. ResultsEA improved motor function and reduced regulated neuronal cell death in SCI rats. Transcriptomic analysis demonstrated the activation of immune- and inflammation-related pathways post-SCI, including NOD-like receptors, nuclear factor-kappa B(NF-κB), and Toll-like receptor (TLR) pathways. EA primarily influenced intestinal inflammation and autoimmune functions. 16S rDNA sequencing illustrated that EA did not alter the diversity of gut microbiota. However, EA altered the gut microbiota composition in SCI rats, increasing Lactobacillus and Akkermansia genera while rebalancing the Firmicutes/Bacteroidetes ratio. Furthermore, depletion of gut microbiota by antibiotics disrupted the intestinal barrier, reduced the expression of intestinal barrier proteins Zonula Occludens-1 (ZO-1) and Occludin, elevated serum lipopolysaccharide-binding protein (LBP) levels, exacerbated spinal cord tissue damage, and hindered motor function recovery in SCI rats. FMT from donors treated with EA reduced LBP levels in the intestine, blood, and spinal cord of rats, inhibited the TLR4 myeloid differentiation primary response protein 88 (MyD88)-NF‑κB pathway and NLRP3-dependent pyroptosis, and improved motor function. On the other hand, FMT treatment resulted in decreased body weight and food intake, whereas FMT using EA-treated donors effectively alleviated these alterations. ConclusionEA effectively alleviated neuroinflammatory responses in rats with SCI, primarily through regulating the gut microbiota and suppressing the NLRP3-dependent pyroptosis signaling pathway.
5.Compound Xishu Granules Inhibit Proliferation of Hepatocellular Carcinoma Cells by Regulating Ferroptosis
Yuan TIAN ; Yuxi WANG ; Zhen LIU ; Yuncheng MA ; Hongyu ZHU ; Xiaozhu WANG ; Qian LI ; Jian GAO ; Weiling WANG ; Wenhui XU ; Ting WANG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(2):37-45
ObjectiveTo study the mechanism of compound Xishu granules (CXG) in inhibiting the proliferation of hepatocellular carcinoma cells by regulating ferroptosis. MethodsThe transplanted tumor model of human Huh7 was established with nude mice and the successfully modeled mice were randomized into model, Fufang Banmao (0.21 g·kg-1), low-dose (1.87 g·kg-1) CXG, medium-dose (3.74 g·kg-1) CXG, and high-dose (7.49 g·kg-1) CXG groups. Mice were administrated with drinking water or CXG for 28 days, and the body weight and tumor volume were measured every 4 days. Hematoxylin-eosin staining was employed to observe the histopathological changes of tumors. The cell-counting kit-8 (CCK-8) was used to examine the survival rate of Huh7 cells treated with different concentrations (0, 31.25, 62.5, 125, 250, 500, 1 000 mg·L-1) of CXG for 24 h and 48 h. CA-AM, DCFH-DA, and C11-BODIPY581/591 fluorescent probes were used to determine the intracellular levels of ferrous ion (Fe2+), reactive oxygen species (ROS), and lipid peroxide (LPO), respectively. The colorimetric method was employed to measure the levels of glutathione (GSH) and superoxide dismutase (SOD). Western blot was employed to determine the protein levels of glutathione peroxidase 4 (GPX4), transferrin receptor 1 (TFR1), and ferritin heavy chain 1 (FTH1), respectively. ResultsIn the animal experiment, compared with the model group, the drug treatment groups showed reductions in the tumor volume from day 12 (P<0.01). After treatment, the Fufang Banmao and low-, medium-, and high-dose CXG groups had lower tumor volume, relative tumor volume, and tumor weight than the model group (P<0.05), with tumor inhibition rates of 48.99%, 79.93%, 91.38%, and 97.36%, respectively. Moreover, the CXG groups had lower tumor volume and relative tumor volume (P<0.05 in all the three dose groups) and lower tumor weight (P<0.05 in medium-dose and high-dose groups) than the Fufang Banmao group. Compared with the model group, the drug treatment groups showed reduced number of tumor cells, necrotic foci with karyopyknosis, nuclear fragmentation, and nucleolysis, and the high-dose CXG group showed an increase in the proportion of interstitial fibroblasts. In the cell experiment, compared with the blank group, CXG reduced the survival rate of Huh7 cells in a dose-dependent manner after incubation for 24 h and 48 h (P<0.05). Compared with the blank group, the RSL3 group and the low-, medium-, and high-dose CXG groups showed a decrease in the relative fluorescence intensity of CA-AM and increases in the fluorescence intensity of DCFH-DA and fluorescence ratio of C11-BODIPY581/591, which indicated elevations in the levels of Fe2+ (P<0.01), ROS (P<0.05), and LPO (P<0.01), respectively. Compared with the blank group, the RSL3 and low-, medium-, and high-dose CXG groups showed lowered levels of GSH and SOD (P<0.05). In addition, the RSL3 group and the medium- and high-dose CXG groups showed down-regulated expression of GPX4 and FTH1 (P<0.05), and the low- and high-dose CXG groups presented up-regulated expression of TFR1 (P<0.05). ConclusionCXG suppresses the proliferation of hepatocellular carcinoma cells by inducing ferroptosis via downregulating the GSH-GPX4 signaling axis and increasing intracellular Fe2+and LPO levels.
6.Gut microbiota characteristics of children with cyclic vomiting syndrome complicated with constipation
Ningning LI ; Yuan LI ; Lin SONG ; Yanyan DU ; Jian WANG ; Lina JI ; Xiwei XU
Chinese Pediatric Emergency Medicine 2025;32(4):286-291
Objective:To investigate the characteristics of gut microbiota distribution in children with cyclic vomiting syndrome(CVS)complicated by constipation.Methods:The children with CVS, aged from 1 to 16 years, who were admitted to Beijing Tsinghua Changgung Hospital from June 2022 to January 2024, were divided into constipation group and normal group(non-constipation group) according to whether they were complicated with constipation or not.The clinical data and stool samples of children were collect. The abundance, diversity and composition of intestinal flora in fecal samples of two groups were detected by metagenomics sequencing.Results:A total of 20 children with CVS were collected, including 10 patients in constipation group and 10 patients in normal group.There were no significant differences in general demographic data between the two groups, including age at admission, age at first onset, body mass index, gender distribution, disease severity, endoscopic findings, and abdominal pain patterns.Microbiome analysis yielded 470 operational taxonomic units (OTUs), with 414 OTUs identified in normal group and 56 OTUs in constipation group. The abundance and diversity of intestinal flora in constipation group were significantly lower than those in normal group. Principal coordinate analysis and principal component analysis indicated significant structural differences in gut microbiota composition between the two groups. LEfSe analysis revealed distinct taxonomic patterns between the two groups, with the normal group demonstrating predominant representation of Firmicutes at the phylum level, while the constipation group showed higher relative abundance of Bacteroidetes and Actinobacteria. KEGG pathway analysis revealed that the carbon metabolism pathways was significantly enriched in the constipation group.Conclusion:There are significant differences in intestinal flora between CVS children with and without comorbid constipation.Bacteroides and Actinomycetes play an important role in constipation of children with CVS. The diversity and metabolic function of intestinal flora may be one of the pathological mechanisms of CVS complicated with constipation.
7.Transthoracic Echocardiography-guided Double Cavity Permanent Pacemaker Implantation in Pregnant Women:Two Cases Report
Huayuan YUAN ; Mingpeng FU ; Yulong GUO ; Jian LI ; Zhiling LUO ; Yu QIAO ; Guodong NIU ; Tao GUO
Chinese Circulation Journal 2025;40(9):922-925
X-ray is usually used to determine anatomy and localization during conventional permanent pacemaker implantation.But X-ray exposure might induce radiation injury to fetus.In this paper,we reported 2 cases successful double cavity permanent pacemaker implantation in pregnant women woman at 13 weeks of gestation under the guidance of transthoracic echocardiography.The postoperative pacing parameters were good,the whole process was finished with zero radiation,and there were complications during pregnancy.Both cases resulted in full-term pregnancies and the natural delivery of healthy newborns.Pacemaker electrodes were in normal position as confirmed by post-delivery X-ray examinations.
8.Current status and trends of research on animal models of postmenopausal osteoporosis:a bibliometric visualization analysis
Xiaoyun ZHANG ; Kunjian LI ; Jian MO ; Yuan CHAI ; Yourong HUANG
Chinese Journal of Tissue Engineering Research 2025;29(14):3070-3080
BACKGROUND:In recent years,postmenopausal osteoporosis has been widely concerned by the society.With the gradual deepening of the research on animal models,animal models have become an important means of modern traditional Chinese medicine research as well as the experimental basis.Therefore,it is particularly important to understand the current status,hotspots,and development trend of the research on animal models.OBJECTIVE:To analyze the research status,hotspots,and development trend of animal models of postmenopausal osteoporosis at home and abroad,and to provide a certain theoretical foundation and reference basis for subsequent research.METHODS:Using"Subject=Postmenopausal osteoporosis AND Subject line=Mouse+Rabbit+Dog+Pig+Sheep+Monkey+Fish+Laboratory animals+Animal experimentation"in Chinese as the search formula,we searched for relevant literature published from January 1,1999 to October 1,2023 in CNKI and WanFang databases.Meanwhile,the articles published from January 1,1999 to October 1,2023 in the Web of Science Core Collection database were searched using"TS=(Postmenopausal osteoporosis)AND TS=(mouse OR mice OR rat OR rabbit OR dog OR swine OR pig OR sheep OR monkey OR fish OR flies OR"laboratory animal"OR"experiment animal"as the search formula.CiteSpace software was applied to visualize and analyze the authors,institutions,countries,keywords,and literature co-citations.RESULTS AND CONCLUSION:(1)After analyzing and screening,1 238 documents were included in the CNKI and WanFang databases,and 3 419 documents were included in the Web of Science Core Collection database.The overall number of articles issued since 1999 has been on an upward trend,with the highest research centrality in the United States,the highest number of articles issued in China.Moreover,the institution with the highest research centrality is the University of California.(2)After removing the keywords directly related to the article topics and synthesizing the co-occurrence frequency and centrality,"biomechanics,""Zuo Gui Wan,""alendronate,""breast cancer,"and"biochemical indicators"are in the core of the research field.(3)According to the analysis of co-citations,among the top 10 cited documents,5 of them are related to the treatment measures and clinical efficacy of postmenopausal osteoporosis.(4)Based on the analysis of keywords and co-cited literature,investigations on osteoblast formation and the mechanism of bone formation,the mechanism of metabolomics,the treatment of traditional Chinese medicine,signaling pathway,parathyroid hormone treatment,and sclerostin antibody treatment are the hot research topics now and the future research trends.
9.Effect of walking-cognition dual-task training combined with active self-disclosure on elderly patients with acute ischemic stroke
Qinqin HU ; Xueying SHI ; Anna WANG ; Pengchao WU ; Qin ZHOU ; Jiaojiao LI ; Xing YUAN ; Jian LI
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2025;27(2):197-201
Objective To observe the effect of specialist team-led walking-cognition dual-task train-ing combined with active self-disclosure on control and balance abilities in elderly patients with acute ischemic stroke(AIS).Methods A total of 90 elderly AIS patients treated in our hospital from January 2022 to January 2024 were enrolled and randomly assigned into the control group and the observation group,with 45 cases in each group.The control group received routine walk-ing training,while the observation group received specialist team-led walking-cognition dual-task training combined with active self-disclosure intervention.Control ability,balance ability,walking ability,cognitive function and psychological status were compared between the two groups.Results After intervention,the scores of Sheikh Trunk Control Scale and Fugl-Meyer Assessment(FMA),and the static balance score,dynamic balance score and total score of Berg Balance Scale(BBS)were significantly increased in both the observation and the control groups(P<0.05),and all above scores were obviously higher in the former group than the latter one(P<0.01).The two groups also obtained notably shorter single-and dual-task walking time after intervention,but there were no statistical difference in the single-task walking time in both groups before and after intervention(P>0.05).After intervention,the observation group had significantly shorter dual-task walking time(22.87±7.36 s vs 27.52±8.71 s,P=0.008)and lower walking time cost of dual task[(11.16±4.07)%vs(25.61±7.82)%,P=0.000]when compared with the control group.After intervention,the scores of Mini-Mental Status Examination were increased,and the scores of Hamilton Depression Rating Scale and Hamilton Anxiety Rating Scale were decreased in the two groups(P<0.05).Conclusion Specialist team-led walking-cognition dual-task training com-bined with active self-disclosure intervention can effectively improve trunk control ability,balance ability,walking ability,cognitive function and psychological state in elderly AIS patients,has cer-tian clinical application value.
10.Progress in regulatory role of macrophages in mucosal healing during in-flammatory bowel disease
Keqi CHEN ; Yaobin LI ; Haoxian CHEN ; Yiming CUI ; Jian HONG ; Hui YUAN
Chinese Journal of Pathophysiology 2025;41(9):1807-1813
Inflammatory bowel disease(IBD)is a chronic,nonspecific inflammatory condition of the intes-tine.However,its pathogenesis and molecular mechanisms remain elusive.The primary therapeutic goal for IBD is to achieve complete restoration of the intestinal mucosa.Despite various treatment strategies available in clinical practice,options to effectively promote mucosal healing remain limited.Macrophages play a pivotal role in maintaining intestinal ho-meostasis,modulating inflammatory responses,and facilitating mucosal healing.This review explores the significance and regulatory mechanisms of macrophages in intestinal mucosal healing,with particular emphasis on modulating macrophage phenotypic switching in the treatment of IBD.Furthermore,this review provides a theoretical basis for precision medicine in IBD treatment,highlighting valuable insights for more targeted therapeutic approaches.

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