1.Therapeutic effects of adipose-derived mesenchymal stem cells and their exosomes on dexamethasone-induced sarcopenia in mice
Weiyuan YUAN ; Qinhui LEI ; Xiuqi LI ; Tiezhu LU ; Ziwen FU ; Zhili LIANG ; Shaoyang JI ; Yijia LI ; Yu REN
Chinese Journal of Tissue Engineering Research 2026;30(1):58-67
BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P<0.01).After 7 days(P<0.01,P<0.01)and 10 days(P<0.01,P<0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P<0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P<0.05,P<0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P<0.01,P<0.01,P<0.01,P<0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.
2.Determination of toluene and chlorobenzene in food-contact recycled polyethylene terephthalate by headspace gas chromatography-mass spectrometry
Runhua WANG ; Xuheng FU ; Song YU ; Yu’e JIN ; Dasheng LU ; Guoquan WANG
Journal of Environmental and Occupational Medicine 2026;43(3):363-367
Background Toluene and chlorobenzene have been designated as surrogate contaminants in the challenge test for evaluating the safety of recycling processes for food-contact recycled polyethylene terephthalate (rPET). Establishing a reliable analytical method is essential for ensuring the compliant use of rPET and safeguarding food safety. Objective To develop a rapid quantitative method for determining toluene and chlorobenzene in rPET using headspace gas chromatography-mass spectrometry (HS-GC-MS), as part of the challenge test for process safety evaluation. Methods The effects of different chromatographic columns and headspace conditions on detection of target analytes were investigated. Three columns HP-5 ms UI (30 m×0.25 mm×0.25 μm), DB-624 (30 m×0.32 mm×1.8 μm), and VF-WAXms (30 m×0.25 mm×0.25 μm) were compared for separation efficiency and peak shape. Headspace equilibration temperatures (50-100 ℃) and equilibration times (10-30 min) were evaluated to determine the optimal instrumental parameters. The effect of sample grinding on recovery was assessed to select the best pretreatment conditions. The established method was validated for selectivity, linearity, sensitivity, accuracy, and precision, and was subsequently applied to the analysis of 12 rPET samples. Results The target analytes achieved good separation and response within 15 min, under the optimized conditions using an HP-5 ms UI column, a headspace equilibration temperature of 60 ℃ and a 10 min equilibration time. Direct analysis without grinding yielded satisfactory recovery rates. Toluene and chlorobenzene showed excellent linearity (
3.Multidimensional analysis of concurrent proximal bronchiolar adenoma and lung carcinoma
Lu-Yao LI ; Gong-Ming DONG ; Yun-Peng ZHANG ; Ting-Ting WANG ; Fu-Quan JIA ; Guan-Jun ZHANG
Journal of Pathology and Translational Medicine 2026;60(3):356-363
Bronchiolar adenoma (BA) is a rare type of lung tumor characterized by bilayered epithelial cells having a continuous basal layer and a luminal layer. It resembles mucinous adenocarcinoma (MA) on frozen section, with difficulty in distinguishing the basal layer. Immunohistochemistry is the best choice for verifying the diagnosis. This study aimed to comprehensively characterize three cases of BA-combined carcinoma using clinical, histopathological, and genetic features. BA and carcinoma sections were subjected to next-generation sequencing, respectively. It was hypothesized that while different mutation forms matched different regions, BA and lung adenocarcinoma shared the same gene mutation when they co-occurred in the same location. BA with extensive carcinoma is extremely rare and presents diagnostic challenges due to its overlap with conditions such as MA. Because of its distinctive morphological characteristics, BA may be regarded as a low-grade malignancy, particularly during a confusing evaluation. A multifaceted examination of clinical, radiological, immunohistochemical, and genetic data is necessary for an accurate diagnosis.
4.Therapeutic effects of adipose-derived mesenchymal stem cells and their exosomes on dexamethasone-induced sarcopenia in mice
Weiyuan YUAN ; Qinhui LEI ; Xiuqi LI ; Tiezhu LU ; Ziwen FU ; Zhili LIANG ; Shaoyang JI ; Yijia LI ; Yu REN
Chinese Journal of Tissue Engineering Research 2026;30(1):58-67
BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P<0.01).After 7 days(P<0.01,P<0.01)and 10 days(P<0.01,P<0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P<0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P<0.05,P<0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P<0.01,P<0.01,P<0.01,P<0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.
5.Clinicopathological characteristics and diagnostic strategies of prostatic paraganglioma presenting with prostatic mass and micturition-associated symptoms
Mengjie ZHANG ; Qun LU ; Yao FU ; Qing ZHANG ; Weidong GAN ; Hongqian GUO
Journal of Modern Urology 2026;31(6):552-558
Objective To evaluate the clinical characteristics, diagnostic reasoning, and therapeutic strategies of prostatic paraganglioma (PPG) to provide an evidence-based foundation for early diagnosis and precision treatment of this rare malignancy. Methods The clinical data of a patient with PPG admitted to our hospital were retrospectively analyzed. Concurrently, a systematic search was conducted across domestic and international databases, including PubMed, CNKI, and Wanfang.Clinical manifestations, laboratory tests, pathological features, therapeutic modalities, and prognostic data of 24 cases reported between 1979 and 2025 were pooled with the institutional case for a comprehensive analysis (n=25). Results Epidemiological features: the age at onset ranged from 8 to 76 years, with a mean age of (44.6±15.2) years, predominantly affecting young and middle-aged adults (30-50 years).Notably, 20.0% (5/25) of the patients exhibited characteristic micturition-associated catecholamine release symptoms (e.g., post-micturition palpitations, transient hypertension).Laboratory findings: among the 19 patients who underwent catecholamine metabolite testing, 14 (73.7%) showed significant elevation in serum or urinary norepinephrine and methoxyadrenaline levels.Pathological and immunohistochemical features: the positivity rate for neuroendocrine markers (chromogranin A, synaptophysin, and neuron-specific enolase) was 100%, while the negativity rate for prostate-specific markers (prostate-specific antigen and prostate-specific acid phosphatase) was also 100%.Treatment and prognosis: surgical intervention was performed in 96.0% (24/25) of the patients, including radical prostatectomy (37.5%), precision tumor excision (25.0%), and transurethral resection (12.5%).Favorable outcomes without recurrence were observed in 89.5% (17/19) of the total cohort. Conclusion PPG is clinically exceedingly rare.The disease should be highly suspected in patients presenting with a prostatic mass, normal prostate-specific antigen level, and micturition-associated cardiovascular symptoms.Testing for catecholamine metabolites is the key screening tool.Robot-assisted surgery facilitates precise tumor excision while ensuring optimal functional preservation.Given the malignant potential and genetic correlations of PPG, lifelong follow-up is recommended.
6.Research advances on RPL11 in the regulation of cellular stress induced by ionizing radiation
Hongyu BAO ; Yan LU ; Chenyu ZHAO ; Mingxuan BI ; Jinghong FU ; Yong ZHANG ; Lian YU ; Weiguo LI
Chinese Journal of Radiological Health 2026;35(2):286-291
Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.
7.Research advances on RPL11 in the regulation of cellular stress induced by ionizing radiation
Hongyu BAO ; Yan LU ; Chenyu ZHAO ; Mingxuan BI ; Jinghong FU ; Yong ZHANG ; Lian YU ; Weiguo LI
Chinese Journal of Radiological Health 2026;35(2):286-291
Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.
8.Research advances on RPL11 in the regulation of cellular stress induced by ionizing radiation
Hongyu BAO ; Yan LU ; Chenyu ZHAO ; Mingxuan BI ; Jinghong FU ; Yong ZHANG ; Lian YU ; Weiguo LI
Chinese Journal of Radiological Health 2026;35(2):286-291
Radiotherapy is a cornerstone in the treatment of malignant tumors. It induces DNA damage through high-energy radiation, preferentially eliminating rapidly proliferating tumor cells. However, its clinical efficacy is often limited by tumor radioresistance and collateral damage to normal tissues. Consequently, elucidating the cellular response mechanisms to radiation stress and identifying key targets that can both sensitize tumor cells and protect normal tissues have become critical strategies for improving radiotherapy outcomes. Radiation stress triggers structural remodeling of the nucleolus, leading to the dissociation of certain ribosomal proteins from the ribosome and enabling them to acquire extra-ribosomal functions. Among these, RPL11 can be released and specifically binds to MDM2, thus inhibiting its E3 ubiquitin ligase activity, stabilizing p53, and mediating cell cycle arrest and apoptosis. The RPL11-MDM2-p53 pathway, acting as a signaling hub that links nucleolar dysfunction to cell fate determination, plays a pivotal role in maintaining genomic stability and regulating cellular responses to radiation. This review first introduces the basic characteristics of RPL11 and elucidates the molecular basis of radiation-induced ribosomal stress. It then outlines the core regulatory mechanisms of the cell cycle. On this basis, it focuses on the mechanisms by which radiation-induced RPL11 regulates the cell cycle and analyzes the specific effects of RPL11 on cell cycle. Furthermore, it discusses the role of the RPL11-MDM2-p53 pathway in cell cycle regulation. Finally, it explores the role of this pathway in maintaining genomic stability and determining cell fate, and highlights its potential value as a target for radiosensitization, aiming to provide new perspectives for enhancing tumor radiosensitivity and reducing damage to normal tissues.
9.Mechanism of Huangqi Chifengtang in Treating Atherosclerosis Based on 16S rRNA Sequencing and Metabolomics
Yuqin LIANG ; Jiaqi FU ; Yunhe SHI ; Fang LU ; Donghua YU ; Shumin LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):94-103
ObjectiveTo investigate the mechanism of action of Huangqi Chifengtang (HQCFT) on rats with atherosclerosis (AS) by regulating the gut microbiota and their metabolites. MethodsA rat model of AS was induced through high-fat diet feeding and vitamin D3 injection, and the modeling lasted for 12 weeks. Fifty eight-week-old male SD rats were randomly divided into five groups: A blank group, a model group, a group receiving a low dose of HQCFT at 1.53 g·kg-1 (HQCFT-L group), a group receiving a high dose of HQCFT at 3.06 g·kg-1 (HQCFT-H group), and a group receiving atorvastatin calcium tablets at 1.8 mg·kg-1 (Ato group), with 10 rats in each group. Oral gavage administration started on the day after model establishment, once daily for four weeks. The efficacy of HQCFT was verified using aortic hematoxylin-eosin (HE) staining and determination of lipid levels and hemorrheology. The real-time polymerase chain reaction (Real-time PCR) was used for detecting inflammatory factor levels in the aorta, high-throughput sequencing for analyzing the gut microbiota composition in intestinal contents, targeted metabolomics for detecting short-chain fatty acid (SCFA) levels, and non-targeted metabolomics for identifying metabolomic profiles of intestinal contents. ResultsCompared with that in the blank group, the aortic tissue of rats in the model group showed significant AS lesions, including endothelial damage, inflammatory infiltration, and formation of fibrous plaques and calcified foci. Moreover, serum triacylglycerol (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels were significantly elevated (P<0.05), while high-density lipoprotein cholesterol (HDL-C) levels were significantly reduced (P<0.05). Significant increases were observed in whole blood viscosity, plasma viscosity, and the mRNA expression levels of NOD-like receptor pyrin domain containing 3 (NLRP3), Caspase-1, interleukin (IL)-β, IL-6, and tumor necrosis factor-α (TNF-α) in aortic tissue (P<0.05). Additionally, gut microbiota composition, SCFA levels, and metabolomic profiles were significantly altered. Compared with those in the model group, serum TC, TG, and LDL-C levels, as well as the whole blood viscosity and plasma viscosity, were significantly reduced in all groups treated with HQCFT (P<0.05). Significant decreases were observed in NLRP3 mRNA expression levels in all groups treated with HQCFT, Caspase-1, IL-β, and IL-6 mRNA expression levels in the HQCFT-H group, and TNF-α mRNA expression levels in the HQCFT-L group (P<0.05). HQCFT reversed the increase in the F/B ratio and dialled back the decrease in the relative abundance of Blautia and the increase in that of Desulfovibrio. HQCFT promoted the production of acetic acid, valeric acid, and propionic acid. Non-targeted metabolomics identified 39 differential metabolites, which were mainly enriched in metabolic pathways such as arachidonic acid metabolism and primary bile acid biosynthesis. ConclusionThe mechanism by which HQCFT ameliorates AS injury may be related to the improvement of dyslipidemia and body inflammatory responses by altering gut microbiota composition, promoting SCFA production, and regulating the levels of metabolites in intestinal contents.
10.Randomized Double-blind Placebo-controlled Study on Clinical Efficacy and Mechanism of Shexiang Baoxinwan in Treating Stable Angina Pectoris Complicated with Anxiety and Depression in Coronary Artery Disease
Jie WANG ; Linzi LONG ; Zhiru ZHAO ; Feifei LIAO ; Jieming LU ; Tianjiao LIU ; Yuxuan PENG ; Hua QU ; Changgeng FU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):159-169
ObjectiveTo evaluate the efficacy of Shexiang Baoxinwan in treating stable angina pectoris with Qi stagnation and blood stasis syndrome in patients with coronary artery disease (CAD) complicated with anxiety and depression and explore its underlying mechanisms. MethodsThis study employed a randomized, double-blind, and placebo-controlled clinical trial design. Patients admitted to the hospital were randomly assigned to the observation group and the control group, with 52 patients in each group. Patients in the observation and control groups received Shexiang Baoxinwan and placebo, respectively, both in combination with conventional Western medication. The dose was 45.0 mg, three times daily, for a total duration of eight weeks. The primary outcome was the Seattle Angina Questionnaire (SAQ) scores before and after treatment. Secondary outcomes included changes in traditional Chinese medicine (TCM) syndrome score, the patient health questionnaire-9 (PHQ-9), generalized anxiety disorder-7 (GAD-7), inflammatory markers [interleukin-18 (IL-18), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), CD40, etc.], monoamine neurotransmitters [e.g., dopamine (DA)], vascular endothelial function markers [e.g., endothelin-1(ET-1)], adipokines, and ischemia-modified albumin (IMA). Adverse reactions were also recorded. ResultsA total of 92 patients completed the study, with 44 in the observation group and 48 in the control group. Compared with baseline, both groups showed significant decreases in PHQ-9, GAD-7, and TCM syndrome scores following treatment (P<0.05), along with a significant increase in SAQ scores (P<0.05). In the observation group, DA levels were significantly increased (P<0.05), while levels of IL-18, TNF-α, CD40, ET-1, and IMA were decreased (P<0.05). In contrast, the control group exhibited significantly increased CD40 levels (P<0.05). Compared with the control group after treatment, the observation group showed significant improvements in the SAQ dimensions of physical limitation, angina stability, treatment satisfaction, and disease perception, as well as in TCM syndrome score, PHQ-9 score, IL-18, CD40, ET-1, and IMA (P<0.05). No adverse reactions were observed in either group during treatment. ConclusionShexiang Baoxinwan can improve anxiety and depression, alleviate angina symptoms, and reduce TCM symptoms of Qi stagnation and blood stasis in CAD patients. The mechanism may involve anti-inflammation, improvement of vascular endothelial function, reduction of IMA, and increase of monoamine neurotransmitter levels.

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