1.Nuclear Factor-κB Signaling Mediates Antimony-induced Astrocyte Activation.
Tao ZHANG ; Yu Dan ZHENG ; Man JIAO ; Ye ZHI ; Shen Ya XU ; Piao Yu ZHU ; Xin Yuan ZHAO ; Qi Yun WU
Biomedical and Environmental Sciences 2021;34(1):29-39
Objective:
Antimony (Sb) has recently been identified as a novel nerve poison, although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear. This study aimed to assess the effects of the nuclear factor kappa B (NF-κB) signaling pathway on antimony-induced astrocyte activation.
Methods:
Protein expression levels were detected by Western blotting. Immunofluorescence, cytoplasmic and nuclear fractions separation were used to assess the distribution of p65. The expression of protein in brain tissue sections was detected by immunohistochemistry. The levels of mRNAs were detected by Quantitative real-time polymerase chain reaction (qRT-PCR) and reverse transcription-polymerase chain reaction (RT-PCR).
Results:
Antimony exposure triggered astrocyte proliferation and increased the expression of two critical protein markers of reactive astrogliosis, inducible nitric oxide synthase (iNOS) and glial fibrillary acidic protein (GFAP), indicating that antimony induced astrocyte activation
Conclusion
Antimony activated astrocytes by activating the NF-κB signaling pathway.
Animals
;
Antimony/toxicity*
;
Astrocytes/metabolism*
;
Cell Line, Tumor
;
Cell Proliferation/drug effects*
;
Glial Fibrillary Acidic Protein/metabolism*
;
MAP Kinase Kinase Kinases
;
Male
;
Mice, Inbred ICR
;
NF-kappa B/metabolism*
;
Nitric Oxide Synthase Type II/metabolism*
;
Rats
;
Signal Transduction/drug effects*
2.Chronic Intermittent Hypobaric Hypoxia Ameliorates Renal Vascular Hypertension Through Up-regulating NOS in Nucleus Tractus Solitarii.
Na LI ; Yue GUAN ; Yan-Ming TIAN ; Hui-Jie MA ; Xiangjian ZHANG ; Yi ZHANG ; Sheng WANG
Neuroscience Bulletin 2019;35(1):79-90
Chronic intermittent hypobaric hypoxia (CIHH) is known to have an anti-hypertensive effect, which might be related to modulation of the baroreflex in rats with renal vascular hypertension (RVH). In this study, RVH was induced by the 2-kidney-1-clip method (2K1C) in adult male Sprague-Dawley rats. The rats were then treated with hypobaric hypoxia simulating 5000 m altitude for 6 h/day for 28 days. The arterial blood pressure (ABP), heart rate (HR), and renal sympathetic nerve activity (RSNA) were measured before and after microinjection of L-arginine into the nucleus tractus solitarii (NTS) in anesthetized rats. Evoked excitatory postsynaptic currents (eEPSCs) and spontaneous EPSCs (sEPSCs) were recorded in anterogradely-labeled NTS neurons receiving baroreceptor afferents. We measured the protein expression of neuronal nitric oxide synthase (nNOS) and endothelial NOS (eNOS) in the NTS. The results showed that the ABP in RVH rats was significantly lower after CIHH treatment. The inhibition of ABP, HR, and RSNA induced by L-arginine was less in RVH rats than in sham rats, and greater in the CIHH-treated RVH rats than the untreated RVH rats. The eEPSC amplitude in NTS neurons receiving baroreceptor afferents was lower in the RVH rats than in the sham rats and recovered after CIHH. The protein expression of nNOS and eNOS in the NTS was lower in the RVH rats than in the sham rats and this decrease was reversed by CIHH. In short, CIHH treatment decreases ABP in RVH rats via up-regulating NOS expression in the NTS.
Animals
;
Baroreflex
;
physiology
;
Blood Pressure
;
drug effects
;
Hypertension
;
metabolism
;
Hypoxia
;
chemically induced
;
Kidney
;
drug effects
;
metabolism
;
Male
;
Nitric Oxide Synthase Type I
;
drug effects
;
metabolism
;
Rats, Sprague-Dawley
;
Solitary Nucleus
;
metabolism
3.The protective effects of vitamin E on lung injury caused by high temperature and PM in COPD rats.
Jiang-Tao LIU ; Bin LUO ; Xiao-Tao HE ; Lan-Yu LI ; Sheng-Gang XU
Chinese Journal of Applied Physiology 2019;35(4):293-296
OBJECTIVE:
To investigate the effects of vitamin E on the respiratory function impairment in rats with chronic obstructive pulmonary disease (COPD) after exposed to high temperature and PM.
METHODS:
Fifty-four 7-week-old SPF male Wistar rats were randomly divided into 9 experimental groups (n=6). The rat COPD model was established by lipopolysaccharide (LPS) and smoke exposure. After modeled, the rats were tracheal instilled with PM (0 mg/ml, 3.2 mg/ml) and intraperitoneally injected with vitamin E at the dose of 40 mg/kg (20 mg/ml). Part of rats (high temperature groups) were then exposed to high temperature (40℃), once (8 h) a day for three consecutive days. After the last exposure, the lung function of rats was detected. The expression levels of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α) and monocyte chemotactic protein-1 (MCP-1) were detected by corresponding ELISA kits.
RESULTS:
Compared with the control group, exposure of high temperature and PM could inhibit the lung function of COPD rats significantly (P<0.05); the level of MCP-1 was increased significantly in PM-exposure groups (P<0.05); iNOS was increased significantly in the groups of high temperature (P<0.05). Compared with the single-PM exposure groups, TNF-α in lung was decreased in the normal temperature health group and high temperature COPD group (P<0.05) after treated with vitamin E; MCP-1 was decreased in all vitamin E-treated groups (P<0.05); the decreased iNOS only appeared in the group of high temperature with vitamin E treatment.
CONCLUSION
High temperature and PM could aggravate the inflammation of COPD rats. As an antioxidant, vitamin E may protect the lung from the damage effects.
Animals
;
Chemokine CCL2
;
metabolism
;
Hot Temperature
;
adverse effects
;
Lung
;
physiopathology
;
Male
;
Nitric Oxide Synthase Type II
;
metabolism
;
Particulate Matter
;
adverse effects
;
Pulmonary Disease, Chronic Obstructive
;
drug therapy
;
Random Allocation
;
Rats
;
Rats, Wistar
;
Tumor Necrosis Factor-alpha
;
metabolism
;
Vitamin E
;
pharmacology
4.Effects of apple polyphenols on monocrotaline-induced pulmonary vascular remodeling in rats and its mechanism.
Shu-Hao ZHANG ; Si-Ming SHAO ; Fang-Zheng CHEN ; Jing ZHU ; Luo-Wei CHEN ; Heng WANG ; Xin-Hui XIANG ; Lin-Bo YUAN
Chinese Journal of Applied Physiology 2019;35(3):209-214
OBJECTIVE:
To investigate the effects of apple polyphenols on pulmonary vascular remodeling in rats with pulmonary arterial hypertension and its mechanism.
METHODS:
Rats were randomly divided into 4 groups:control (Con) group, monocrotaline (MCT) group, apple polyphenol (APP) group,monocrotaline + apple polyphenol (MCT+APP) group. In Con group, rats received a subcutaneous injection of physical saline. In APP group, rats received intraperitoneal injection of 20 mg/kg APP, every other day. In MCT group, rats received a single subcutaneous injection of MCT(60 mg/kg). In MCT+APP group, rats received subcutaneous injection of 60 mg/kg MCT followed by an intraperitoneal injection of 20 mg/kg APP every other day. All the disposal lasted 3 weeks. Then the PAH-relevant indicators, such as mean pulmonary artery pressure(mPAP), pulmonary vascular resistance(PVR), right ventricular hypertrophy index (RVHI) ,wall thickness (WT%) and wall area (WA%) were tested. After that, the inflammatory pathway related indicators, such as interleukin1(IL-1),interleukin1(IL-6), tumor necrosis factor α(TNF-α), cyclooxygenase 2(COX-2) and myeloperoxidase(MPO) in pulmonary tissue and free intracellular Ca in pulmonary smooth muscle cell(PASMC), content of eNOS and NO in endothelial cells were determined.
RESULTS:
Compared with the control group, the levels of mPAP, PVR, RVHI, WA%, WT%, and IL-1, IL-6, TNF-α, COX-2, MPO in tissue and the expression of Ca in PASMC of MCT group were increased significantly, while the contents of eNOS and NO in endothelial cells were decreased significantly (P<0.05). Compared with the MCT group, the apple polyphenol treatment could improve the above mentioned situation, and the COX-2 and Ca indicators of the apple polyphenol treatment group were decreased significantly (P<0.05).
CONCLUSION
MCT can increase COX-2 expression and intracellular Ca in pulmonary artery smooth muscle cells, decrease the contents of eNOS and NO in endothelial cells, while apple polyphenols can significantly inhibit these effects.
Animals
;
Calcium
;
metabolism
;
Cyclooxygenase 2
;
metabolism
;
Cytokines
;
metabolism
;
Malus
;
chemistry
;
Monocrotaline
;
Nitric Oxide
;
metabolism
;
Nitric Oxide Synthase Type III
;
metabolism
;
Polyphenols
;
pharmacology
;
Pulmonary Artery
;
drug effects
;
pathology
;
Random Allocation
;
Rats
;
Vascular Remodeling
;
drug effects
5.The effects of Xiaotan Huayu Liqiao formula on mesenteric artery function in rats exposed to chronic intermittent hypoxia.
Fu-Yang YU ; Sheng-Chang YANG ; Ya-Jing GUO ; Ya-Shuo ZHAO ; Si-Wen LIU ; En-Sheng JI
Chinese Journal of Applied Physiology 2019;35(3):204-208
OBJECTIVE:
To investigate the effects of Xiaotan Huayu Liqiao formula (the Chinese Medicine) on mesenteric artery function in rats exposed to chronic intermittent hypoxia (CIH), and to explore the related mechanism.
METHODS:
Forty-eight male SD rats were randomly divided into four groups as Normoxia, CIH, Formula+CIH and formula group. Rats were exposed to normoxia in the Normoxia and Formula group, or intermittent hypoxia in CIH or Formula+CIH group. Xiaotan Huayu Liqiao formula was given at 24g/kg by intragastric administration before intermittent hypoxia exposure. The pathological changes of mesenteric artery were determined by HE staining, and the relaxation of mesenteric artery (induced by acetylcholine(ACh) and L-arginine(L-Arg)) was recorded by microvascular ring technique. Serums of all rats were collected (0 d and 21 d) and the content of NO was detected by ELISA. The levels of endothelial nitric oxide synthase (eNOS) and p-eNOS were measured by Western blot.
RESULTS:
Compared with Normoxia group, the mesenteric arterial endothelial injury and media thickening were observed and the relaxation of mesenteric artery was significantly reduced in rats exposed to CIH. The level of NO in serum and the ratio of p-eNOS/eNOS were also decreased in the CIH group. Xiaotan Huayu Liqiao formula administration improved the pathologic changes and dilatation function of mesenteric artery, increased the levels of NO and p-eNOS. Compared with Normoxia group,all the results were not observed significant difference in Formula group.
CONCLUSION
Xiaotan Huayu Liqiao formula increased the bioavailability of NO, and ameliorated the CIH induced mesenteric artery function injury.
Acetylcholine
;
Animals
;
Drugs, Chinese Herbal
;
pharmacology
;
Hypoxia
;
pathology
;
Male
;
Mesenteric Arteries
;
drug effects
;
pathology
;
Nitric Oxide
;
metabolism
;
Nitric Oxide Synthase Type III
;
metabolism
;
Random Allocation
;
Rats
;
Rats, Sprague-Dawley
6.Cardamine komarovii flower extract reduces lipopolysaccharide-induced acute lung injury by inhibiting MyD88/TRIF signaling pathways.
Qi CHEN ; Ke-Xin ZHANG ; Tai-Yuan LI ; Xuan-Mei PIAO ; Mei-Lan LIAN ; Ren-Bo AN ; Jun JIANG
Chinese Journal of Natural Medicines (English Ed.) 2019;17(6):461-468
In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower (CKF) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2 (PGE2), production of pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages (PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors (IL-1β, TNF-α, and IL-6) in bronchoalveolar lavage fluid (BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes iNOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1β, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating MyD88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1β in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.
Acute Lung Injury
;
chemically induced
;
drug therapy
;
genetics
;
metabolism
;
Adaptor Proteins, Vesicular Transport
;
genetics
;
metabolism
;
Animals
;
Anti-Inflammatory Agents
;
administration & dosage
;
chemistry
;
Cardamine
;
chemistry
;
Cyclooxygenase 2
;
genetics
;
metabolism
;
Female
;
Flowers
;
chemistry
;
Humans
;
Lipopolysaccharides
;
adverse effects
;
Male
;
Mice
;
Myeloid Differentiation Factor 88
;
genetics
;
metabolism
;
NF-kappa B
;
genetics
;
metabolism
;
Nitric Oxide Synthase Type II
;
genetics
;
metabolism
;
Plant Extracts
;
administration & dosage
;
chemistry
;
Signal Transduction
;
drug effects
;
Tumor Necrosis Factor-alpha
;
genetics
;
metabolism
7.Two new ursane-type nortriterpenes from Lonicera macranthoides and their iNOS-inhibitory activities.
Yu-Dan MEI ; Nan ZHANG ; Wei-Yang ZHANG ; Jin-Shan TANG ; Hua ZHOU ; Yang YU ; Xin-Sheng YAO
Chinese Journal of Natural Medicines (English Ed.) 2019;17(1):27-32
The flower buds of Lonicera macranthoides (Shan Yin-Hua), represent an important traditional Chinese medicine and food ingredient. A phytochemical investigation of the 70% EtOH extract of the flower buds of L. macranthoides resulted in the isolation of 12 triterpenoids (1-12), including two new ursane-type nortriterpenes, 2α, 24-dihydroxy-23-nor-ursolic acid (1) and 2α, 4α-dihydroxy-23-nor-ursolic acid (2). Their structures were established by multiple spectroscopic methods and comparison with literature data. All isolated compounds were evaluated for their anti-inflammatory effects in LPS-activated RAW264.7 cells. Compounds 1 and 2 exhibited inhibitory effects on iNOS at the concentration of 30 μmol·L.
Animals
;
Anti-Inflammatory Agents
;
chemistry
;
pharmacology
;
Drugs, Chinese Herbal
;
chemistry
;
Enzyme Inhibitors
;
chemistry
;
pharmacology
;
Ethanol
;
chemistry
;
Flowers
;
chemistry
;
Lonicera
;
chemistry
;
Macrophages
;
drug effects
;
metabolism
;
Mice
;
Molecular Structure
;
Nitric Oxide
;
metabolism
;
Nitric Oxide Synthase Type II
;
antagonists & inhibitors
;
Plant Extracts
;
chemistry
;
Plants, Edible
;
chemistry
;
RAW 264.7 Cells
;
Triterpenes
;
chemistry
;
pharmacology
8.The effects of single versus combined therapy using LIM-kinase 2 inhibitor and type 5 phosphodiesterase inhibitor on erectile function in a rat model of cavernous nerve injury-induced erectile dysfunction.
Min Chul CHO ; Junghoon LEE ; Juhyun PARK ; Sohee OH ; Ji Sun CHAI ; Hwancheol SON ; Jae-Seung PAICK ; Soo Woong KIM
Asian Journal of Andrology 2019;21(5):493-500
We aimed to determine whether combination of LIM-kinase 2 inhibitor (LIMK2i) and phosphodiesterase type-5 inhibitor (PDE5i) could restore erectile function through suppressing cavernous fibrosis and improving cavernous apoptosis in a rat model of cavernous nerve crush injury (CNCI). Seventy 12-week-old Sprague-Dawley rats were equally distributed into five groups as follows: (1) sham surgery (Group S), (2) CNCI (Group I), (3) CNCI treated with daily intraperitoneal administration of 10.0 mg kg-1 LIMK2i (Group I + L), (4) daily oral administration of 20.0 mg kg-1 udenafil, PDE5i (Group I + U), and (5) combined administration of 10.0 mg kg-1 LIMK2i and 20.0 mg kg-1 udenafil (Group I + L + U). Rats in Groups I + L, I + U, and I + L + U were treated with respective regimens for 2 weeks after CNCI. At 2 weeks after surgery, erectile response was assessed using electrostimulation. Penile tissues were processed for histological studies and western blot. Group I showed lower intracavernous pressure (ICP)/mean arterial pressure (MAP), lower area under the curve (AUC)/MAP, decreased immunohistochemical staining for alpha-smooth muscle (SM) actin, higher apoptotic index, lower SM/collagen ratio, increased phospho-LIMK2-positive fibroblasts, decreased protein kinase B/endothelial nitric oxide synthase (Akt/eNOS) phosphorylation, increased LIMK2/cofilin phosphorylation, and increased protein expression of fibronectin, compared to Group S. In all three treatment groups, erectile responses, protein expression of fibronectin, and SM/collagen ratio were improved. Group I + L + U showed greater improvement in erectile response than Group I + L. SM content and apoptotic index in Groups I + U and I + L + U were improved compared to those in Group I. However, Group I + L did not show a significant improvement in SM content or apoptotic index. The number of phospho-LIMK2-positive fibroblasts was normalized in Groups I + L and I + L + U, but not in Group I + U. Akt/eNOS phosphorylation was improved in Groups I + U and I + L + U, but not in Group I + L. LIMK2/cofilin phosphorylation was improved in Groups I + L and I + L + U, but not in Group I + U. Our data indicate that combined treatment of LIMK2i and PDE5i immediate after CN injury could improve erectile function by improving cavernous apoptosis or eNOS phosphorylation and suppressing cavernous fibrosis. Rectification of Akt/eNOS and LIMK2/cofilin pathways appears to be involved in their improvement.
Animals
;
Apoptosis/drug effects*
;
Arterial Pressure
;
Electric Stimulation
;
Erectile Dysfunction/pathology*
;
Lim Kinases/antagonists & inhibitors*
;
Male
;
Nerve Crush
;
Nitric Oxide Synthase Type III/metabolism*
;
Penis/pathology*
;
Peripheral Nerve Injuries/pathology*
;
Phosphodiesterase 5 Inhibitors/therapeutic use*
;
Phosphorylation
;
Pyrimidines/therapeutic use*
;
Rats
;
Rats, Sprague-Dawley
;
Sulfonamides/therapeutic use*
9.Evodiamine Inhibits Angiotensin II-Induced Rat Cardiomyocyte Hypertrophy.
Na HE ; Qi-Hai GONG ; Feng ZHANG ; Jing-Yi ZHANG ; Shu-Xian LIN ; Hua-Hua HOU ; Qin WU ; An-Sheng SUN
Chinese journal of integrative medicine 2018;24(5):359-365
OBJECTIVETo investigate the effects of evodiamine (Evo), a component of Evodiaminedia rutaecarpa (Juss.) Benth, on cardiomyocyte hypertrophy induced by angiotensin II (Ang II) and further explore the potential mechanisms.
METHODSCardiomyocytes from neonatal Sprague Dawley rats were isolated and characterized, and then the cadiomyocyte cultures were randomly divided into control, model (Ang II 0.1 μmol/L), and Evo (0.03, 0.3, 3 μmol/L) groups. The cardiomyocyte surface area, protein level, intracellular free calcium ([Ca]) concentration, activity of nitric oxide synthase (NOS) and content of nitric oxide (NO) were measured, respectively. The mRNA expressions of atrial natriuretic factor (ANF), calcineurin (CaN), extracellular signal-regulated kinase-2 (ERK-2), and endothelial nitric oxide synthase (eNOS) of cardiomyocytes were analyzed by real-time reverse transcriptionpolymerase chain reaction. The protein expressions of calcineurin catalytic subunit (CnA) and mitogen-activated protein kinase phosphatase-1 (MKP-1) were detected by Western blot analysis.
RESULTSCompared with the control group, Ang II induced cardiomyocytes hypertrophy, as evidenced by increased cardiomyocyte surface area, protein content, and ANF mRNA expression; increased intracellular free calcium ([Ca]) concentration and expressions of CaN mRNA, CnA protein, and ERK-2 mRNA, but decreased MKP-1 protein expression (P<0.05 or P<0.01). Compared with Ang II, Evo (0.3, 3 μmol/L) significantly attenuated Ang II-induced cardiomyocyte hypertrophy, decreased the [Ca] concentration and expressions of CaN mRNA, CnA protein, and ERK-2 mRNA, but increased MKP-1 protein expression (P<0.05 or P<0.01). Most interestingly, Evo increased the NOS activity and NO production, and upregulated the eNOS mRNA expression (P<0.05).
CONCLUSIONEvo signifificantly attenuated Ang II-induced cardiomyocyte hypertrophy, and this effect was partly due to promotion of NO production, reduction of [Ca]i concentration, and inhibition of CaN and ERK-2 signal transduction pathways.
Angiotensin II ; Animals ; Atrial Natriuretic Factor ; metabolism ; Calcineurin ; genetics ; metabolism ; Calcium ; metabolism ; Dual Specificity Phosphatase 1 ; genetics ; metabolism ; Extracellular Signal-Regulated MAP Kinases ; genetics ; metabolism ; Hypertrophy ; Myocytes, Cardiac ; drug effects ; metabolism ; pathology ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Quinazolines ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Rats, Sprague-Dawley
10.Quercetin modulates iron homeostasis and iNOS expression of splenic macrophages in a rat model of iron deficiency anemia.
Maryam MAZHAR ; Nurul KABIR ; Shabana U SIMJEE
Chinese Journal of Natural Medicines (English Ed.) 2018;16(8):580-589
Iron deficiency anemia is one of the most common micronutrient deficient conditions around the globe with various consequences, including the weakened immune system. Quercetin is widely distributed bioflavonoid; it has been debated for its dual roles in iron regulation. Quercetin-iron interaction in the body is a complex mechanism which has not been completely understood. The present study aimed to investigate the effect of quercetin on iron supplementation in iron deficiency anemia and on iNOS expression in splenic macrophages. The rat model of iron deficiency anemia was induced by feeding low iron diet to weanling rats for 20 days. The animals were then administered with ferrous sulfate, quercetin, and their combination for 30 days. Blood parameters, histopathological analysis, iron storage, CD68, iNOS and SLC40 expression in rat spleen were investigated. Our results showed that quercetin regulated iron absorption, despite SLC40 down-expression, indicating possible alternate route of iron transport, and that quercetin modulated iNOS production in splenic macrophages.
Anemia, Iron-Deficiency
;
drug therapy
;
genetics
;
metabolism
;
Animals
;
Dietary Supplements
;
analysis
;
Female
;
Homeostasis
;
drug effects
;
Humans
;
Iron
;
deficiency
;
Macrophages
;
drug effects
;
metabolism
;
Nitric Oxide Synthase Type II
;
genetics
;
metabolism
;
Quercetin
;
administration & dosage
;
Rats
;
Rats, Sprague-Dawley
;
Spleen
;
drug effects
;
enzymology

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