Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add filters








Language
Year range
1.
Chinese Journal of Digestion ; (12): 14-18, 2022.
Article in Chinese | WPRIM | ID: wpr-934128

ABSTRACT

Objective:To explore the marking method for magnetically controlled capsule gastroscopy (MCCG) pictures with artificial intelligence (AI), so as to improve the work efficiency of endoscopist and to reduce the blind area of AI image reading.Methods:According to the consensus of MCCG, 24 parts of stomach in 14 775 pictures of MCCG from 35 subjects in Shenzhen Zifu Medical Technology Co., Ltd received MCCG from March to August, 2020 were marked by ten gastroenterologists and one developer of MCCG with medical background, the marking shape included rectangles and polygons. Among the ten gastroenterologists, three were senior endoscopist (the total number of gastroenteroscopy operations over 80 000, chief physician or associate chief physician), four were medium seniority endoscopist (the total number of gastroenteroscopy operations between 10 000 and 80 000, associate chief physician), and three were junior endoscopist (the total number of gastroenteroscopy operations less than 10 000, attending physician). The pictures of the same subject were pre-marked by two selected senior endoscopists with blind method, and the standard of marking with most appropriate coincidence rate was determined. The qualified marked pictures were automatically learn with AI deep learning method, and the learning results were fed back. Chi square test was used for statistical analysis.Results:According to the pre-marked results, the standard of coincidence rate for rectangular marking area was set as 50.0% and that for polygon marking area was 70.0%. The first correction for qualified rate was 39.0% (5 762/14 775). A total of 9 013 pictures were corrected. After repeated training and correction for one to five times, all pictures were qualified marked. The marking qualified rate of senior endoscopist partners was higher than that of partners of different qualifications (48.7%, 1 200/2 466 vs. 19.0%, 825/4 337), and the difference was statistically significant ( χ2=659.20, P<0.001). There was no statistically significant difference in the marking qualified rate between the senior endoscopist partners and partners of senior endoscopist and capsule developer (48.7%, 1 200/2 466 vs. 49.6%, 1 496/3 019; P>0.05). Conclusions:Establishment of AI marking method for MCCG can provide technical support for AI non-blind area reading, and AI non-blind area monitoring during the operation of MCCG.

2.
Chinese Pharmacological Bulletin ; (12): 973-978,979, 2014.
Article in Chinese | WPRIM | ID: wpr-599297

ABSTRACT

Aim To investigate the mechanism of demethylation on adenosine (ADO )and homocysteine (HCY)-induced apoptosis in human hepatoma HepG2 cells .Methods HepG 2 cells were treated with differ-ent concentrations of ADO (1.0、2.0、4.0 mol · L-1 ) alone or in combination with HCY for 6h,12h and 24h,5-aza-2-deoxycytidine (5-Aza-CdR)as a positive control.Cell viabilities were assessed by CCK8 assay. Cell apoptosis was observed by AnnexinV-FITC/PI staining.The mitochondrial membrane potentials(ΔΨ) were measured by flow cytometry.The mRNA and pro-tein expressions of caspase-3,caspase-8,caspase-9, MDM-2,p53,Cytochrome C,DNMT1,DNMT3a,DN-MT3 b were detected by RT-qPCR and Western blot re-spectively.Results ADO alone or in combination with HCY significantly reduced the viability of HepG2 cells in a dose and time-dependent manner.The apoptotic rates of HepG2 cells after combination treatment with ADO and HCY at 1 .0,2.0,4.0 mol · L-1 for 24 h were (1 8.63 ± 1.25 )%,(29.42 ±2.37 )% and (42.47 ±3.09 )%,compared with the control group (1.30 ±0.82 )%,P <0.01;and the mitochondrial membrane potentials were decreased from 674.15 ± 82.8%(black control group)to (428.38 ±54.5)%, (297.78 ±30.5)%,(74.45 ±5.73)%,P<0.01, respectively.The expressions of caspase-3,caspase-8, caspase-9,MDM-2,p53,Cytochrome C were up-regula-ted and MDM-2 were down-regulated after combination treatment of ADO and HCY.The mRNA expressions of DNMT1 ,DNMT3 a and DNMT3 b were down-regulated after combination treatment with ADO and HCY or 5-Aza-CdR alone.Conclusion Combination treatment of ADO and HCY can cause cellular methylation chan-ges.The effects of demethylation of ADO and HCY may activate p53 gene and mitochondrial pathway, which at last leads to HepG2 cell apoptosis.

3.
Chinese Journal of Pathophysiology ; (12): 2155-2160, 2014.
Article in Chinese | WPRIM | ID: wpr-457508

ABSTRACT

[ ABSTRACT] AIM:To investigate the effects of tanshinone IIA ( Tan IIA) on proliferation, apoptosis and its mo-lecular mechanism in human hepatoma HepG2 cells under hypoxic condition.METHODS:Hypoxia model was established by treatment with cobalt chloride ( CoCl2 ) .The cells were divided into normoxia control group, hypoxia control group and hypoxia combined at different concentrations of Tan IIA groups.After HepG2 cells were incubated with different concentra-tions of Tan IIA (0.5, 1.0, 2.0, 5.0 and 10.0 mg/L) for 24 h, 48 h and 72 h under hypoxic condition, the cell prolifer-ation was determined by MTT assay.After Tan IIA was added to the media at different concentrations for 24 h and 48 h, the apoptotic cells were observed by Hoechst 33258 staining.The protein levels of hypoxia-inducible factor 1 alpha (HIF-1α) , vascular endothelial growth factor ( VEGF) and wild-type P53 were detected by Western blotting after cultured with different concentrations of Tan IIA for 48 h.RESULTS:Tan IIA inhibited the proliferation of HepG2 cells in a dose-and time-dependent manner.Tan IIA induced the typical morphology of apoptotic cells and increased the apoptotic rate in a dose-and time-dependent manner after treatment with 1.0 mg/L~5.0 mg/L for 24 h and 48 h under hypoxic condition. The protein levels of HIF-1αand VEGF were weakly expressed in HepG2 cells under normoxia but up-regulated after incu-bated under hypoxia for 48 h.The protein expression of HIF-1αand VEGF were decreased with the increase in the concen-tration of Tan IIA under hypoxia.The protein expression of wild-type P53 was increased with the increase in the concentra-tions of Tan IIA under hypoxia.CONCLUSION:Tan IIA significantly inhibits the proliferation and induces the apoptosis of human hepatoma HepG2 cells under hypoxia, which may be related to the down-regulation of HIF-1αand VEGF and up-regulation of wild-type P53.

SELECTION OF CITATIONS
SEARCH DETAIL