1.Receiver operating characteristic curve evaluation on computed radiography: an experimental study
Zixi YU ; Changyuan WANG ; Yue XU ; Jindong XIE ; Menglong ZHANG ; Jian WANG
Chinese Journal of Radiology 2001;0(05):-
Objective To get the maximum information from computed radiography (CR) output images by changing post-processing parameters. Methods Six experimental photos of polypropylene balls of 2.0 mm in diameter were taken by means of one time X-ray exposing on an imaging plate (IP) with different post-processing parameters including rotation amount (GA), gray gradation type (GT), rotation center (GC), shifting amount (GS), frequency rank (RN), frequency type (RT), and degree of enhancement (RE). 6 photos were viewed by three students and one radiologist on a 6 000 lx illuminance viewbox. Receiver operating characteristic (ROC) curves were made by means of 5-value-differentiation method. Results The largest mean area value (Az) below ROC curves of a low contrast experimental photo with post-processing parameters GA=1.0,GT=A, GC=1.6, GS=0.3, RN=4.0, RT=R and RE=3.0 was 0.96, and the maximum information was obtained. The smallest mean area value (Az) was 0.78 with changed post-processing parameters GA=0.8, GS=-0.2 and RE=0.5 while other parameters were not changed. The minimum information was obtained from this photo. Conclusion In order to get the maximum information from a CR output image, the post-processing parameters should be suitably selected.
2.Protective effects of catalpol on cardio-cerebrovascular diseases:A comprehensive review
Zixi ZHANG ; Yongguo DAI ; Yichao XIAO ; Qiming LIU
Journal of Pharmaceutical Analysis 2023;13(10):1089-1101
Catalpol,an iridoid glucoside isolated from Rehmannia glutinosa,has gained attention due to its potential use in treating cardio-cerebrovascular diseases(CVDs).This extensive review delves into recent studies on catalpol's protective properties in relation to various CVDs,such as atherosclerosis,myocardial ischemia,infarction,cardiac hypertrophy,and heart failure.The review also explores the compound's anti-oxidant,anti-inflammatory,and anti-apoptotic characteristics,emphasizing the role of vital signaling pathways,including PGC-1a/TERT,PI3K/Akt,AMPK,Nrf2/HO-1,estrogen receptor(ER),Nox4/NF-κB,and GRP78/PERK.The article discusses emerging findings on catalpol's ability to alleviate diabetic cardiovascular complications,thrombosis,and other cardiovascular-related conditions.Although clinical studies specifically addressing catalpol's impact on CVDs are scarce,the compound's established safety and well-tolerated nature suggest that it could be a valuable treatment alternative for CVD patients.Further investigation into catalpol and related iridoid derivatives may unveil new opportunities for devising natural and efficacious CVD therapies.
3.Radiation shielding for the intraoperative radiotherapy using low energy X-rays
Daguang ZHANG ; Zixi ZHU ; Jiana SUN ; Yuan TIAN ; Wei WANG
Chinese Journal of Radiological Medicine and Protection 2022;42(8):629-635
Objective:To assess the shielding requirements of low energy X-ray intraoperative radiotherapy room under the domestic and foreign standards and guidelines, to measure the sured transmission factors for a range of shielding materials, the ambient dose equivalent rate around concerned positions and the shielding effect of protective devices, so as to provide references for shielding design of such radiotherapy units and applications of radiological protection devices.Methods:The required shielding thicknesses for a treatment room with INTRABEAM intraoperative radiotherapy system were calculated under the Chinese national standard GBZ 121, IPEM report No. 75 and NCRP report No. 151, respectively. The transmission factors for a range of shielding materials including solid water slab, shielding sheet and shielding apron were measured. Moreover, the ambient dose equivalent rates were measured under the simulated working conditions and the shielding effectiveness of a lead screen was evaluated.Results:The required lead thicknesses calculated under different standards and guidelines were less than 0.6 mm for all the concerned points, with the differences at sub-millimeter level. The low energy X-rays generated by this equipment attenuated rapidly in the shielding materials. The measured transmission factors of 0.05 mm lead equivalent shielding sheet and 0.25 mm lead equivalent shielding apron were 0.068 and 0.003 8, respectively. When the radiation was delivered using spherical applicator without any attenuation, the ambient dose equivalent rates at 1 m and 2 m from the X-ray source were 10.7 and 2.6 mSv/h, respectively. The corresponding measurement values decreased to 3.8 and 0.9 μSv/h, respectively, when the spherical applicator was inserted into a small water tank. Meanwhile, the ambient dose equivalent rate at 2 m was reduced to the background level when using protective screen.Conclusions:The shielding requirements for a low energy X-ray intraoperative radiotherapy facility are minimal, with low effective energy of X-rays generated by this equipment, but the dose rate close to the unshielded radiation source is high. The shielding scheme of treatment room should be optimized in design and the protective device should be used in a reasonable way.
4.Inhibitory effects of ursolic acid on IL-6-mediated invasion and migration of breast cancer cells
Rongrong LIU ; Tao ZHANG ; Fenfen XIANG ; Zixi CHEN ; Mengzhe ZHANG ; Xiangdong KANG ; Rong WU
China Pharmacy 2023;34(8):955-960
OBJECTIVE To investigate the inhibitory effects of ursolic acid on interleukin-6 (IL-6)-mediated invasion and migration of breast cancer MDA-MB-231 cells (hereinafter referred to as “231 cells”). METHODS The effects of 20, 40, 80, 160 and 320 µmol/L ursolic acid on the proliferation rate of 231 cells were measured by CCK-8 method. The breast cancer 231 cells were divided into control group, model group and administration group. The migration and invasion abilities of cells were detected by scratch assay and Transwell assay. Real-time quantitative polymerase chain reaction (q-PCR) assay and Western blot assay were used to detect the mRNA and protein expressions of epithelial-mesenchymal transition-related makers such as E cadherin (E-cad), matrix metalloprotein 2 (MMP2), MMP9, vimentin (Vim), CD44 molecule (CD44) and aldehyde dehydrogenase 1 family member A1 (ALDH1A1). The phosphorylation levels of JAK2 and STAT3 in the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway (in terms of p-JAK2/JAK2 ratio and p-STAT3/STAT3 ratio) were detected by Western blot assay. RESULTS A low concentration of ursolic acid of 20 µmol/L (no significant inhibitory effect on cell proliferation ability) was selected as the subsequent administration concentration. Compared with the control group, the migration and invasion abilities of cells in the model group were significantly enhanced (P<0.05); compared with the model group, the migration and invasion abilities of cells in the administered group were significantly reduced (P<0.05). Compared with the control group, the relative mRNA and protein expressions of epithelial-mesenchymal transition-related markers MMP9, MMP2, Vim, ALDH1A1 and CD44 were all elevated to different extents, and the mRNA and protein expressions of E-cad were all decreased to different extents in the model group cells, and part of the differences had statistical significance (P<0.05), the p-JAK2/JAK2 ratio and p-STAT3/STAT3 ratio were significantly increased in the model group (P<0.05); compared with the model group, the expressions of the above indicators were reversed to some extent in the administration group. CONCLUSIONS Ursolic acid blocks the activation of JAK2/STAT3 signaling pathwby the inflammatory factor IL-6, which ultimately interrupts the invasion and metastasis of breast cancer cells.