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1.
AIM: To study the inducing effect of human mutant p27 gene on apoptosis of the colorectal cancer cells. METHODS: The recombinant adenovirus Ad-p27mt was constructed to infect the colorectal cancer cell SW480. The inducing effect of Ad-p27mt on apoptosis in colorectal cancer cells was measured by flow cytometry, DNA fragment analysis and TUNEL method. RESULTS: Ad-p27mt was successfully constructed. When the multiplicity of infection (MOI) was ≥50, the infection efficiency reached 100%. After 24 h of infection, there was an apoptotic hypodiploid peak observed by flow cytometry before G1 and there were apoptotic characteristic bands in the DNA electrophoresis. The apoptotic index detected by TUNEL method was 82.6±3.2 (Ad-p27mt group) and 5.0±3.5 (control group), respectively, the difference of which was significant (P<0.01). CONCLUSION: Human mutant p27 gene transfection effectively induces apoptosis in the colorectal cancer cells.  相似文献   

2.
AIM: To investigate the effects of double thymidine deoxyribonucleoside (TdR) blocking on the cell cycle of human gastric cancer SGC-7901 cells.METHODS: SGC-7901 cells in the logarithm period were selected in the study and treated with TdR at concentration of 2 mmol/L, 4 mmol/L or 8 mmol/L for 15 h as the first blocking. After incubation in TdR-free medium for 10 h, the cells were treated with TdR at same concentrations again for another 15 h as the second blocking. The blocked cells were released by washing in fresh medium twice and incubation in TdR-free medium containing 10% fetal bovine serum for 12 h. The cells were collected and the cell cycle was detected by flow cytometry.RESULTS: By double TdR (2 mmol/L, 4 mmol/L and 8 mmol/L) blocking to synchronize the cell cycle, the cells in G0/G1 phase accounted for 77.3%, 77.5% and 77.0%, respectively. After further incubation for 12 h in TdR-free medium, the proportion of the cells in each phase of the cell cycles returned to normal range. CONCLUSION: The method of double TdR blocking is an ideal access in short term to acquire a large number of cells in G0/G1 phase.  相似文献   

3.
AIM:To investigate the inhibitory effects of Cl- channel blocker, tamoxifen, on volume-activated Cl- currents of nasopharyngeal carcinoma cells (CNE-2Z cells) in G1 and S phases. METHODS:Highly synchronous cells in G1 phase and S phase were obtained by the serum starvation and the double-block techniques. The whole-cell patch clamp technique was used to observe the effects of tamoxifen on volume-activated Cl- currents and to analyze the anion permeability of volume-activated Cl- channels. RESULTS:47% hypotonic stimulation activated a Cl- current in the nasopharngeal carcinoma cells at the cell cycle stage G1 phase and S phase. Tamoxifen at concentration of 10 to 30 μmol/L completely inhibited the current. However, the time needed to completely inhibit the current was dose-dependent and was different between G1 phase and S phase. The time needed to completely inhibit the current was shorter in G1 cells than that in S phase cells. The anion permeability sequence of the volume-activated Cl- channel was I->Cl->gluconate in both G1 phase and S phase cells. The permeability of G1 phase cells to I- was higher than that in S phase cells, but to gluconate was lower than that in S phase cells. CONCLUSIONS:The density of the volume-activated Cl- current, the anion permeability of the channel and the sensitivity of the current to tamoxifen were different between the CNE-2Z cells in G1 phase and those in S phase. The results suggest that the expression of tamoxifen-sensitive, volume-activated chloride channels is differentiated at different stages of the cell cycle.  相似文献   

4.
AIM: To investigate the effect of norcantharidin(NCTD)on proliferation and invasion of human breast cancer cell line SKBR3 in vitro and its anticancer mechanisms.METHODS: MTT assay was used to determine SKBR3 cell proliferation. Light and FACScan were used to detect apoptosis and cell cycle. The invasiveness of SKBR3 was evaluated by the adhesion test,Matrigel experiment and the crossing-river test.RESULTS: NCTD had inhibitive effects on growth of SKBR3 cells in a dose and time-dependent manner, with the IC50 value of 12.5 mg/L at 24 h.The cells treated with 10 mg/L NCTD for 24 h and 48 h showed typical apoptotic morphology and hypodiploid peak before G1 phase. The cell cycle was arrested at G2/M phase. The apoptosis percentage was up to 3.44% and 6.17%, and the G2/M percentage was up to 35.82% and 38.70%. NCTD also could inhibit obviously the adhesion, movement and invasive capability simulating human basement membrane of SKBR3. Its effect was also in a dose-dependent manner. In the NCTD-treated group, crossing-river time was prolonged significantly and passing-membrane cells markedly decreased. CONCLUSION: NCTD in vitro inhibits not only the proliferation and growth of human breast cancer cells but also invasion and metastasis of the cells at relatively low concentration. NCTD shows prominent anti-tumor effects.  相似文献   

5.
AIM:To study the apoptosis induction of cyclooxygenase-2 (COX-2) inhibitor,celecoxib and adriamycin (ADM) on tumor apoptosis of gastric carcinoma MGC-803 cells, and to explore their possible molecular mechanism(s) and interactions.METHODS:The number of MGC-803 cells was observed by MTT assay. Tumor apoptosis was studied by fluorescence microscopy, flow cytometry (FCM), and DNA ladder. RESULTS:MGC-803 cell number was significantly decreased with increasing dose of ADM. Cells were accumulated in G0/G1 phase and the number of cells in S phase was decreased. ADM (5 mg/L) combined with celecoxib (25 μmol/L) markably inhibited the growth of MGC-803 cells. Significant morphological changes of typical apoptosis were observed after treatment with combined use of celecoxib and ADM. Compared with ADM or celecoxib alone, ADM plus celecoxib obviously enhanced the DNA ladder fragment revealed by agarose gel electrophoresis of DNA. After exposure to combined celecoxib and ADM treatment for 48 h, MGC-803 cells were accumulated in G0/G1 phase. There was a decrease in the number of cells in S phase as compared to celecoxib or ADM alone. CONCLUSION:Celecoxib and ADM appear to have synergistic effects for the apoptosis induction. This may be an important prospect for applying COX-2 inhibitors to assist chemical therapy of ADM in clinical use.  相似文献   

6.
AIM: To investigate the role of Mcl-1 in the G2/M arrest induced by diallyl disulfide (DADS) in leukemic HL-60 cells.METHODS: The inhibitory effect of DADS on human leukemic HL-60 cells was detected by CCK-8 method in vitro. Flow cytometry analysis was employed to observe the cycle arrest in HL-60 cells and the effect of DADS-induced G2/M arrest on HL-60 cells with Mcl-1 gene knockdown by RNAi silencing. The expression of Mcl-1, PCNA and CDK1 in HL-60 cells treated with DADS was determined by Western blotting. The binding of Mcl-1 with PCNA and CDK1 was detected by coimmuno-precipitation. RESULTS: HL-60 cells were treated with DADS at concentration of 15, 30, 60, 120 or 240 μmol/L for 48 h. The inhibition rates of HL-60 cell proliferation were 31.15%, 55.88%, 66.14%, 75.29% and 80.35%, respectively, and gradually enhanced with the increase in the concentration of DADS (P<0.05). Flow cytometry analysis revealed that the proliferation of HL-60 cells was blocked by DADS in the G2/M phase. Treatment with DADS for 24 h and 48 h at concentrations of 60 μmol/L and 120 μmol/L, the percentage of G2/M phase cells increased as compared to the untreated cells (P<0.05). DADS induced arrest of HL-60 cells in G2/M phase in a time- and dose- dependent manner (P<0.05). The results of Western blot analysis indicated that Mcl-1, PCNA and CDK1 in HL-60 cells were significantly reduced after treated with DADS (P<0.05). HL-60 cell cycle progression delayed by silencing Mcl-1 gene with siRNA technique, suggesting that silence of Mcl-1 gene led to G2/M arrest. Compared to the cells treated with DADS only, the percentage of G2/M cells raised in the cells with Mcl-1 gene silencing and treated with DADS (P<0.05), indicating that Mcl-1 gene silencing enhanced the effect of DADS-induced G2/M arrest in HL-60 cells. The binding of Mcl-1 with PCNA and CDK1 was detected by coimmuno-precipitation and the formation of heterodimers was observed, which was decreased after treated with DADS for 4 h.CONCLUSION: DADS inhibits the proliferation of HL-60 cells and induces its G2/M phase arrest. The decreased expression of PCNA is related to inhibiting the proliferation of leukemic cells. Knockdown of Mcl-1 gene enhances the effect of DADS-induced G2/M arrest.  相似文献   

7.
AIM:To investigate the anti-tumor effect of Weimaining (WMN) on a murine Lewis lung carcinoma (3LL) and the influence on the cell cycle. METHODS:The inhibitory rate of WMN in 3LL growth was detected by replicating the model of 3LL. The effect of the drug on 3LL cell cycle and the influence of the drug on the expression of cyclin D1 protein were investigated by flow cytometry and immunohistochemical staining. RESULTS:The results showed that the inhibitory rate of drug in 3LL is 19.14%, 33.59%, 40.63% and 51.56% respectively at dosage ranging from 100,150, 200 and 250 mg·kg-1·d-1. The drug inhibits tumor growth in a dose-dependent manner. The drug arrests 3LL cells in G0-G1 phase and decreases the expression of cyclin D1 protein. CONCLUSION:WMN inhibits the growth of 3LL cells in vivo by decreasing the expression of cyclin D1, blocking the cells in G0-G1 phase and preventing the cells transition from G1 to S phase while DNA is replicated.  相似文献   

8.
9.
AIM: To study the effect of vitamin K3 (VK3) on the induction of apoptosis in androgen-independent prostate cancer cell PC-3M in vitro.METHODS: Cell viability was estimated by MTT assay. AO/EB staining was performed to detect apoptotic cells. Apoptosis and the changes of cell cycle were detected by flow cytometry. NAC was used to observe the effect of growth inhibition by VK3. RT-PCR was used to confirm the changes in gene expression. Levels of intracellular peroxides were estimated by using an oxidation-sensitive fluorescent probe DCFH-DA. RESULTS: PC-3M cells growth was significantly inhibited by VK3 (≥60 μmol/L, P<0.05). The inhibitory effect was time and dosage dependent. The result of AO/EB staining showed that apoptosis of PC-3M cells were induced by VK3. A typical subdiploid peak before G0/G1 phase was observed after treated for 12 h with VK3 (60 μmol/L) by flow cytometry. The effect of growth inhibition treated with VK3 was antagonized by antioxygen NAC (5, 10, 20, 40, 80 μmol/L). An increase in the level of DCF fluorescence after PC-3M cells were treated for 1-2 h with VK3 was observed. Antioxidase GSH-Px and CAT were run-down after treated with VK3. CONCLUSION: The results indicate that apoptosis in PC-3M cells is induced through oxidative stress by VK3.  相似文献   

10.
11.
AIM: To observe the effects of tissue extracts of injured liver on BEL-7402 cells,and explore a novel strategy of tumor therapy by differentiation induction. METHODS: Differentiation induction of human hepatocellular carcinoma cell line BEL-7402 was carried out with liver tissue extracts from an animal model of liver injury. The changes of cell biological characteristics, such as morphological features of the cells, MTT growth curves and cell cycle distribution, were dynamically observed. RESULTS: After exposed to the tissue extracts of injured liver, the number of mitotic cells was decreased, and the speed of growth and the proliferation of carcinoma cells were slowed down dramatically. The percentage of the cells in G0/G1 phase was increased, while the cells in S phase was decreased. The level of proliferation index (PI) also declined. CONCLUSION: The tissue extracts of injured liver affect the differentiation status of human hepatocellular carcinoma cell line BEL-7402, promote the cell differentiation and reduce the tumor characteristics. The tissue extracts of injured liver possess an important potential as a tumor differentiation inducer.  相似文献   

12.
AIM: To observe the antitumor effect of 5 commonly used chemotherapeutic drugs on 11 human colorectal cancer cell lines in vitro. METHODS: CCK-8 method was used to determine the growth inhibitory effects of 5 antitumor drugs, which were expressed as the half growth inhibitory concentration (IC50) and sensitivity index IC50/PPC (peak plasma concentration) on 11 human colorectal cancer cell lines. The expression variations of heat-shock protein 27 (HSP27) and HSP70 at protein levels in human colorectal tumor cell lines treated with different chemotherapeutic drugs were observed by Western blotting. RESULTS: All the 11 colorectal cancer cell lines were sensitive to 5-fluorouracil (5-FU) and oxaliplatin (OHP) without drug resistant. Five colorectal cancer cell lines were sensitive to mitomycin (MMC), while the other 6 cell lines were moderately sensitive. Ten colorectal cancer cell lines except SW1116 were sensitive to docetaxel (DXL), while SW1116 cells were resistant to DXL. Nine colorectal cancer cell lines except LS174T and SW1116 were moderately sensitive to irinotecan (IFL), and SW1116 cells were also resistant to IFL, while LS174T cells were sensitive to IFL. After treated with the antitumor drugs, HSP27 was up-regulated in HCT116 cells and SW480 cells, while the expression of HSP70 didnt change. CONCLUSION: LS174T cells are multidrug-sensitive, while SW1116 cells are multidrug-resistant. 5-FU and OHP are the wide-spectrum anti-colorectal cancer drugs. Determining the sensitivity to chemotherapeutic drugs and the expression level of HSP27 can improve the accuracy in drug selection.  相似文献   

13.
LIU An  HUANG Cheng-gang  XU Jia 《园艺学报》2016,32(7):1227-1234
AIM: To investigate the therapeutic effects of lentivirus-mediated shRNA targeting growth hormone secretagogue receptor 1a(GHSR1a) on colorectal cancer cell line SW480 both in vitro and in vivo. METHODS: Human GHSR1a sequence was used for the design of shRNA targeting GHSR1a, which was introduced to lentivirus, followed by transfection into SW480 cells. CCK-8 assay was performed to detect cell viability. The mRNA expression of GHSR1a and PTEN in colorectal cancer cells was detected by RT-PCR. The protein levels of GHSR1a, ghrelin, PTEN, p-AKT and p53 were determined by Western blot. Stable GHSR1a silencing in SW480 xenografts in nude mice was established. After the mice were sacrificed and weighted, immunohistochemistry was used to detect the positive expression of Ki-67 and PTEN in the tumors. RESULTS: GHSR1a was over-expressed in the malignant cells in comparison with the normal cells in vitro. The tumor specific lentivirus-mediated shRNA targeting GHSR1a gene and GHSR1a knockdown SW480 cells were successfully constructed. After transfection with GHSR1a shRNA, the expression of GHSR1a at mRNA and protein levels was markedly inhibited in the SW480 cells. Furthermore, GHSR1a silencing by specific shRNA showed increased PTEN, inhibition of AKT phosphorylation and promotion of p53 release in the SW480 cells. In vivo results demonstrated that down-re-gulation of GHSR1a in the SW480 cells significantly decreased the expression of Ki-67 and increased the expression of PTEN in the tumor tissues, leading to a marked reduction in tumor weight in comparison to blank control or negative control tumors. CONCLUSION: Down-regulation of GHSR1a by shRNA technique inhibits the growth of colorectal cancer cell line and xenograft tumor through activation of the PTEN/PI3K/AKT signaling pathways.  相似文献   

14.
AIM: To investigate the effects of rhTGF-β1 and TGF-β1 gene transfection on the proliferation of cultured rabbit corneal endothelial cells in vitro. METHODS: Cell growth induced by various concentrations of rhTGF-β1 was determined by MTT proliferation assay. Under the induction of liposomes, recombinant pSecTag2-TGF-β1MP vectors were transferred into the corneal endothelial cells. Morphological changes of transfected cells were observed by HE staining. The expression levels of TGF-β1 were assessed by ELISA. Cell cycle analysis was assessed by flow cytometry. DNA fragment analysis was used to confirm the presence of apoptosis. RESULTS: rhTGF-β1 in concentrations of 5-20 μg/L showed a significant suppressive effect on the proliferation of corneal endothelial cells, 0.5-1 μg/L had no effect, 0.05-0.1 μg/L facilitated cell growth, as compared with negative controls. The morphous of transfected corneal cells had no significant abnormality compared with normal cells. According to the result of ELISA, the concentration of TGF-β1 in the supernatant was calculated to be (98±3) ng/L. Flow cytometry assay showed that S and G2/M phase of transfected cells decreased significantly compared with that of control group, but the cell cycle recovered normally after adding 10 μg/L EGF into the culture medium. Agarose electrophoresis didn′t show marked ladders in transfected group. CONCLUSION: Effects of rhTGF-β1 on the proliferation of corneal endothelial cells are different with various concentrations. TGF-β1 gene transfection shows suppressive effect on the proliferation of cultured corneal endothelial cells, but does not induce cell apoptosis. EGF is the antagonist of this suppressive effect.  相似文献   

15.
AIM:To study the inhibitory effects of nm23-H1 gene on proliferation and invasion of human lung adenocarcinoma A549 cell line. METHODS:Recombinant eukaryotic expression vector pcDNA3.1-nm23-H1 containing full length of human nm23-H1 cDNA was constructed and transfected into a human lung adenocarcinoma A549 cell line by lipofectamine. Cell strain that expressed nm23-H1 stably was screened out by G418 and named pcDNA-nm23-A549. Expression of nm23-H1 was identified by RT-PCR and immunohistochemistry. Growth curves were drawn to detect the inhibitory effects on cell proliferation. Cell cycle of pcDNA-nm23-A549 was examined by flow cytometry. Atomic force microscopy was used to observe the filopodia on the surface of the cells. RESULTS:Introduction of nm23-H1 obviously inhibited the proliferation of A549. Expression of nm23-H1 did not induce apotosis in A549 cells but increased the percentage of phase G1 cells and decreased phase S cells. Meanwhile, phase G1 to phase S transition was restrained. Filopodia in the cell surface was much fewer and its structure changed in cells transformed. CONCLUSION:nm23-H1 is capable of inhibiting A549 proliferation and decreasing its metastatic ability, probably by interfering with cell cycle and cell surface structure.  相似文献   

16.
AIM: To study the mechanism of oleanolic acid induced apoptosis and its influence on cell cycle in HL-60 cells in vitro. METHODS: The HL-60 cells were treated with different concentrations of oleanolic acid and then cultured for 12 h, 24 h, 48 h and 72 h, respectively. MTT assay was used to evaluate the inhibitory effect of oleanolic acid on HL-60 cells in vitro. The argarose gel electrophoresis was used to detect the chromatin DNA fragmentation. FACS was used to analyze the cell cycle of HL-60 cells. Western blotting was used to detect the activation of caspase-3 which has been confirmed the last execution of apoptosis pathway. RESULTS: MTT assay showed that oleanolic acid dramatically inhibited the growth of HL-60 cells in vitro, more than 50% HL-60 cells were inhibited when the cells were treated with 80 μmol/L oleanolic acid for 48 h; the apparent DNA ladder was detected after exposure of HL-60 cells to oleanolic acid for 48 h. FACS analysis showed that cell cycle of HL-60 cells was arrested in G1 phase, the inhibition ratio of HL-60 cells achieved 63.24% and 67.90% after treated with oleanolic acid for 48 h and 72 h correspondingly. Western blotting detected the activation of caspase-3 after exposure of HL-60 cells to 80 μmol/L oleanolic acid for 48 h. CONCLUSION: These results suggest that oleanolic acid induces apoptosis and the cell cycle of HL-60 cells is arrested in G1 phase.  相似文献   

17.
AIM: To study the target relationship between microRNA-98 (miR-98) and enhancer of Zeste homolog 2 (EZH2), and the effect of miR-98 on the viability and invasion ability of colorectal cancer cells.METHODS: The target relationship between EZH2 and miR-98 was predicted by TargetScan software and confirmed by dual-luciferase reporter assay. The miR-98 mimic and miR-98 inhibitor were transfected into human colorectal cancer SW480 cells and SW620 cells. The protein expression level of EZH2 was determined by Western blot. The cell viability was measured by MTT assay, and the invasion ability was detected by Transwell assay. EZH2 over-expression vector was transfected into the colorectal cancer cells, and the cell viability and invasion ability were measured.RESULTS: miR-98 targeted EZH2 and down-regulated EZH2 protein expression in the SW480 cells and SW620 cells. miR-98 over-expression significantly decreased, while miR-98 knockdown dramatically increased the viability and invasion ability of SW480 cells and SW620 cells. Additionally, EZH2 over-expression enhanced the viability and invasion ability of SW480 cells and SW620 cells.CONCLUSION: miR-98 inhibits the viability and invasion ability of SW480 cells and SW620 cells by targeting EZH2, which may provide new therapeutic target and method for colorectal cancer treatment.  相似文献   

18.
LIU Wei  YANG Yi  QIN Ru-zi  LU Xiu-hong  YANG Yu 《园艺学报》2010,26(11):2112-2117
AIM: To explore the effects of melanoma-associated antigen H1 (Mage-H1) on cell proliferation and differentiation. METHODS: A phase contrast microscope was used to observe the morphological changes of PC12 cells treated with or without nerve growth factor (NGF). The expression of Mage-H1 in pre-and post-differentiated PC12 cells was detected by RT-PCR and Western blotting, and its potential effects on the cell cycle were analyzed by flow cytometry. RESULTS: After induced by NGF for 8 days, over 92% of PC12 cells were differentiated. The relative levels of Mage-H1 mRNA and protein in the differentiated PC12 cells were 4.6 times and 2.6 times higher than those in control cells,respectively. Moreover, the PC12 cells transiently expressed Mage-H1 were significantly arrested in G0-G1 phase as compared to the cells transfected with an empty vector.CONCLUSION: Mage-H1 inhibits the proliferation of PC12 cells and promotes the differentiation of the cells.  相似文献   

19.
AIM: The cancer biology has showed that overexpression of oncogenes is responsible for the progression of human malignancies,antisense technology can block a certain gene expression.Caffeine has enhancement effect on chemotherapy of osteosarcoma cells to cisplatin,we constructed the recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment and investigated its effect on the in vitro sensitivity of osteosarcoma MG-63 cells to cisplatin.METHODS: The recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment was constructed by cloning c-myc cDNA of about 750 base pairs in a reverse direction into adenovirus vector.Ad-Asc-myc and caffeine was used respectively or together to co-operate with cisplatin to treat the osteosarcoma MG-63 cells in vitro,and Western blotting,MTT,flow cytometry (FCM),electron microscope were used to evaluate expression of c-Myc protein,tumor cell proliferation in vitro,apoptosis and cell cycle analysis.RESULTS: Ad-Asc-myc was obtained with the titer of 2×1012 pfu/L.Ad-Asc-myc down-regulated the expression of c-Myc protein,Ad-Asc-myc or caffeine enhanced the effects of 2.0,5.0 mg/L cisplatin on MG-63 cells.Moreover,Ad-Asc-myc combined with caffeine significantly enhanced this effects,not only on cisplatin-induced apoptosis,but also on tumor cells proliferation in vitro.The expression of bcl-2 was downregulated,bax were upregulated,while there was no change in the expression of E2F-1.FCM analysis showed that cisplatin treatment induced a block in S phase,and caffeine reversed this block and speeded up the progression of cells out of the S phase.Ad-Asc-myc induced obvious G2/M phase arrest in transfected cells.CONCLUSION: Ad-Asc-myc combined with caffeine may enhance apoptosis-induced and chemotherapy effects of osteosarcoma MG-63 cells to cisplatin.  相似文献   

20.
SUN Yan  ZHANG Yuan 《园艺学报》2007,23(8):1613-1617
AIM: To purify and investigate the differentiation potentials of fetal liver mesenchymal stem cells (flMSCs) from murine in vitro.METHODS: flMSCs from mouse fetuses at embryonic and fetal day (ED)13.5 or ED14.5 were isolated by adhering to plastic and passaged by modified method.Cell cycle and phenotype were analyzed by flow cytometry.The cell differentiation was induced by special induction media.The cells differentiated to adipose,cartilaginous and osteoid tissues were identified with oil red O,Toluid blue,alkaline phosphatease (ALP) and von Kossa’s staining.The cells differentiated to neural-like cells were detected by RT-PCR and immuno-staining.RESULTS: Fibroblast-like cells predominated in culture.(83.76±2.88)% of flMSCs stayed in the G0/G1 phases.Homogenous cells were positive for mesenchymal lineage markers CD44,CD29,but not for markers of hematopoietic cells CD45,CD11b.flMSCs were able to differentiate into adipogenic,chondrogenic,osteogenic and neurogenic cells.CONCLUSION: flMSCs can be purified by modified plastic-attachment method and have multiple differentiation,which is available to stem cell therapy for various diseases.  相似文献   

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