1.Drug sensitivity assessment of pancreatic cancer cells by real-time cell analysis
Yaxi JIN ; Caixian SUN ; Hong GAO ; Lianfeng ZHANG ; Li ZHANG
Chinese Journal of Comparative Medicine 2017;27(3):25-30
Objective To assess the drug sensitivity of pancreatic cancer cells based on real-time cell analysis and provide a reference for individualized diagnosis and treatment of pancreatic cancer.Methods Three human pancreatic cancer cells lines SW1900, Capan-2 and PANC-1 were selected and treated with gemcitabine hydrochloride and tegafur gimeracil oteracil potassium capsules, respectively.After 24 hours of culture, the cells were treated with the two drugs in gradient concentration.The cell growth curves before and after the drug administration was monitored using a real-time cells analyzer and the growth inhibition rates (IC50) of the drugs of the pancreatic cancer cells were calculated.At the same time, the cells in the cell culture plate were treated with the drug, and acridine orange/ethidium bromide (AO/EB) staining and laser scanning confocal microscopy were performed to observe the changes of cells after the drug administration.Results 72 hours after the drug administration, IC50 values for the three cell lines were different.The IC50 values of gemcitabine hydrochloride for SW1900, Capan-2 and PANC-1 cells were 1.69 μmol/L, 10.05 μmol/L and 12.74 μmol/L, respectively.The IC50 values of tegafur capsule for SW1900, Capan-2 and PANC-1 cells were 180.29 μmol/L, 765.70 μmol/L and 95.57μmol/L, respectively.AO/EB staining confirmed the reliability of IC50.Conclusions SW1900 and Capan-2 cells can be used as the control for gemcitabine hydrochloride and tegafur gimeracil oteracil potassium capsules to establish cell models for drug screening in vitro, which provides a reference for the application of the technology in anticancer drugs screening.
2.Assessment of drug sensitivity of the prostate cancer cells based on real-time cell analysis system
Yaxi JIN ; Caixian SUN ; Hong GAO ; Lianfeng ZHANG ; Li ZHANG
Chinese Journal of Comparative Medicine 2016;26(4):46-52
Objective To develop a more convenient and stable method for assessment of drug sensitivity of prostate cancer based on real-time cell analysis system as a reference for clinical treatment.Methods Human prostate cancer VCaP, DU145, PC-3, PC-3M-2B4 and PC-3M-IE8 cells were chosen to detect the sensitivity to three drugs, docetaxel, cabazitaxel and abiraterone acetate.Serial dilutions of the three drugs were used to treat the cell culture for 24 hours.The drug-induced effects on the cell lines after an incubation of 24 hours were recorded by the real-time cell analysis system to determine the half maximal inhibitory concentration (IC50).Results Docetaxel showd IC50 of 8.81 nmol/L, 11.61 nmol/L, 1.78 nmol/L, 1.44 nmol/L, 8.69 nmol/L for VCaP, DU145, PC-3, PC-3M-2B4, PC-3M-IE8 cells, respectively.Cabazitaxel showed IC50 of 3.73 nmol/L, 3.96 nmol/L, 10.41 nmol/L, 5.43 nmol/L, and 7.37 nmol/L, respectively, for the five cell lines.Abiraterone acetate showed IC50 of 8.34 μmol/L, 8.60 μmol/L, 24.20 μmol/L, 8.59 μmol/L, and 13.21 μmol/L for the five cell lines.Conclusions PC-3M-2B4 and DU145, VCaP and PC-3 cells can be used as control for docetaxel, cabazitaxel and abiraterone acetate to establish cell models for the drug screening in vitro and to provide reference for clinical applications.
3.Establishment and evaluation of the method for detecting HBV DNA in serum using HBV DNA probe labeled directly by alkaline phosphatase.
Yaxi CHEN ; Ailong HUANG ; Zhenyuan QI ; Youlan SHAN ; Hang SUN
Chinese Journal of Hepatology 2002;10(6):429-431
OBJECTIVETo establish a sensitive and specific technique for detecting HBV DNA in serum using HBV DNA probe labeled directly by alkaline phosphatase (AlkPhos Direc probe).
METHODSThe probe that purified HBV DNA sequence was labeled directly by alkaline phosphatase and chemiluminescent substrate CDP-star for AP was used in the hybridization assay. HBV DNA was detected by autoradiography on the film. The test compared the chemiluminescen dot blot hybridization assay for 80 samples with digoxigenin-labeled HBV DNA probe detective method. The correlation of 70 samples test results between fluorescent quantitative HBV DNA PCR method and dot blot hybridization assay by AlkPhos Direc probe was analysed.
RESULTSThe sensitivity of the probe labeled directly by alkaline phosphatase was 10pg at least. The coincidence was 100% compared with digoxigenin-labeled HBV DNA probe detection. A correlation coefficient of HBV DNA quantitative results between fluorescent quantitative HBV DNA PCR (QPCR) method and dot blot hybridization assay by AlkPhos Direc probe was 0.98 (P<0.01).
CONCLUSIONSThe method detecting HBV DNA in serum by HBV DNA AlkPhos Direc probe is sensitive and specific. The results between two methods with AlkPhos Direc and digoxigenin-labeled HBV DNA probe are coincident completely. The correlation of HBV DNA quantitative results between fluorescent QPCR method and dot blot hybridization assay by AlkPhos Direc probe is satisfactory.
Alkaline Phosphatase ; chemistry ; metabolism ; Animals ; DNA Probes ; chemistry ; genetics ; DNA, Viral ; blood ; genetics ; Hepatitis B ; blood ; diagnosis ; virology ; Hepatitis B virus ; genetics ; Humans ; Molecular Diagnostic Techniques ; methods ; standards ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity
4.Automated cephalometric landmark identification and location based on convolutional neural network
Beiwen GONG ; Qiao CHANG ; Feifei ZUO ; Xianju XIE ; Shaofeng WANG ; Yajie WANG ; Yaxi SUN ; Xiuchen GUAN ; Yuxing BAI
Chinese Journal of Stomatology 2023;58(12):1249-1256
Objective:To develop an automated landmark location system applicable to the case of landmark missing.Methods:Four and eighty-one lateral cephalograms, which contained 240 males and 241 females, with an average age of (24.5±5.6) years, taken from January 2015 to January 2021 in the Department of Orthodontics, Capital Medical University School of Stomatology, and met the inclusion criteria were collected. Five postgraduate orthodontic students were the annotators to manually locate 61 possible landmarks in 481 lateral cephalograms. Two assistant professors in the department as reviewers performed calibration. Two professors as arbitrators, made final decision. Data sets were established (341 were used as training set, 40 as validation set, and 100 as test set). In this paper, an automatic landmarks identification and location model based on convolutional neural networks (CNN), CephaNET, was developed. The model was trained by feeding the original image into the feature extraction module and convolutional pose machine (CPM) module to locate landmarks with high accuracy using deep supervision. Training set was enhanced to 1 684 images by histogram equalization, cropping, and adjustment of brightness. The model was trained to compare the Gaussian heat maps output from the network with the set threshold to identify landmark missing cases. Test set of 100 lateral cephalograms was used to test the accuracy of the model. The evaluation criteria used were success detection rate of missing landmark, mean radial error (MRE) and success detection rate (SDR) in the range of 2.0, 2.5, 3.0, 3.5 and 4.0 mm.Results:The model identified and located 61 commonly used landmarks in 0.13 seconds on average. It had an average accuracy of 93.5% in identifying missing landmarks. The MRE of our testing set was (1.19±0.91) mm. SDR of 2.0, 2.5, 3.0, 3.5 and 4.0 mm were 85.4%, 90.2%, 93.5%, 95.4%, 97.0% respectively.Conclusions:The model proposed in this paper could adapt to the absence of landmark in lateral cephalograms and locate 61 commonly used landmarks with high accuracy to meet the requirements of different cephalometric analysis methods.
5. Pathological insights of radiotherapy-related damage to surgical margin after preoperative radiotherapy in patients with rectal cancer
Qinghua ZHONG ; Peihuang WU ; Qiyuan QIN ; Yingyi KUANG ; Tenghui MA ; Huaiming WANG ; Yaxi ZHU ; Daici CHEN ; Jianping WANG ; Lei WANG
Chinese Journal of Surgery 2017;55(7):507-514
Objective:
To investigate the effect of irradiation to anastomosis from preoperative radiotherapy for patients with rectal cancer by studying the pathological changes.
Methods:
In this retrospective study, patients enrolled in the FOWARC study from January 2011 to July 2014 in the Sixth Affiliated Hospital of Sun Yat-Sen University were included. In the FOWARC study, enrolled patients with local advanced rectal cancer were randomly assigned to receive either neoadjuvant chemo-radiotherapy or chemotherapy. Among these patients, 23 patients were selected as radiation proctitis (RP)group, who fulfilled these conditions: (1) received neoadjuvant chemo-radiotherapy followed by sphincter-preserving surgery; (2) developed radiation proctitis as confirmed by preoperative imaging diagnosis; (3) had intact clinical samples of surgical margins. Twenty-three patients who had received neoadjuvant chemo-radiotherapy but without development of radiation proctitis were selected as non-radiation proctitis (nRP) group. Meanwhile, 23 patients received neoadjuvant chemotherapy only were selected as neoadjuvant chemotherapy (CT) group. Both nRP and CT cases were selected by ensuring the basic characteristics such as sex, age, tumor site, lengths of proximal margin and distal margin all maximally matched to the RP group. Both proximal and distal margins were collected for further analysis for all selected cases. Microscopy slices were prepared for hematoxylin & eosin staining and Masson staining to show general pathological changes, and also for immunohistochemistry with anti-CD-34 as primary antibody to reveal the microvessel. Microvessel counting in submucosal layer and proportion of macrovessel with stenosis were used to evaluate the blood supply of the proximal and distal end of anastomosis. A modified semi-quantitative grading approach was used to evaluate the severity of radiation-induced injury. Either ANOVA analysis, Kruskal-Wallis rank-sum test or χ2 test was used for comparison among three groups, and Mann-Whitney