1.Accuracy evaluation of CyberKnife system
Chenfeng CAI ; Liuling ZHU ; Sheng XU ; Yan MENG
Chinese Medical Equipment Journal 2017;38(6):121-123
Objective To evalutate the accuracy of CyberKnife system and measure its relative output factor.Methods The accuracy of target localization of the system was measured with E2E test,film dosimetry,6D-skull tracking mode and fiducial tracking mode.Six kinds of detectors were used to detect the collimators of the system.Results The positioning errors were (0.531 ±0.293) and (0.482±0.297) mm respectively by 6D-skull tracking mode and fiducial tracking mode.The detectors proved the relative output factors of 5-mm collimator were 0.133 ±0.006,0.320±0.010,0.635 ±0.010,0.656±0.009,0.777± 0.013 and 0.680±0.014,and those of 35-mm collimator were 0.983±0.002,0.990±0.002,0.987±0.001,0.992±0.002,0.990± 0.010 and 0.981 ±0.010.Conclusion The total error of CyberKnife system was less than 1 mm.Large collimater has high consistencies between the output factors of the detectors,while there are significant differences between the output factors in case of the collimater with the diameter less than 15 mm.
2.Effects of ethane 1,2-dimethanesulfonate preconditioning on renal ische-mia/reperfusion injury in male rats
Chenfeng BU ; Ganshen YU ; Yin XU ; Zhijian SU ; Yadong HUANG ; Zexuan SU
Chinese Journal of Pathophysiology 2015;(1):54-58
AIM:To investigate the effects of ethane 1,2-dimethanesulfonate (EDS) preconditioning on renal ischemia/reperfusion (I/R) injury in male Sprague-Dawley (SD) rats.METHODS: Male SD rats (n=48) were ran-domly assigned to 6 groups:blank, sham, I/R, EDS+I/R, EDS+testosterone (TST) +I/R, and castration (Cast)+I/R.The renal pedicles were bilaterally occluded with a microvascular clamp for 45 min to establish renal I/R-induced in-jury model.Bilateral orchiectomy was conducted 2 weeks before surgery .EDS (75 mg/kg) was intraperitoneally injected 5 d before operation .Blood samples were collected 24 h after reperfusion from the vena orbitalis posterior plexus .Luteinizing hormone (LH), TST, serum creatinine (SCr), blood urea nitrogen (BUN), and kidney injury molecule-1 (KIM-1) were detected.The renal tissues were harvested to measure the level of TNF-αand the expression of Fas mRNA and caspase-3 protein.RESULTS:Serum TST levels in EDS +I/R group and Cast +I/R group were below the minimum detectable threshold.Compared with other groups , the rats in EDS+I/R group and Cast +I/R group had higher levels of SCr , BUN and KIM-1 (P<0.05).SCr and BUN levels showed no significant difference between EDS +I/R group and Cast +I/R group (P>0.05), but KIM-1 level in EDS+I/R group was lower than that in Cast +I/R group (P<0.05).After reper-fusion for 24 h, the levels of TST and LH in EDS +I/R group, Cast+I/R group and EDS+TST+I/R group were lower than those 1 h before operation (P<0.05).Compared with Cast+I/R and I/R group, the TNF-αlevel and expression of Fas mRNA and caspase-3 protein were significantly decreased in EDS +I/R group ( P<0.05 ) .CONCLUSION: EDS preconditioning substantially reduces the serum TST level , thus attenuating I/R-induced acute renal injury .TNF-α-induced Fas/FasL pathway may be involved in this process .
3.A novel method for fast determination of components in Guizhi Fuling capsule by near infrared spectroscopy.
Kaimin GONG ; Jiachun LI ; Lianmin XU ; Wei XIAO ; Yu'an BI ; Zhenzhong WANG ; Chenfeng ZHANG
China Journal of Chinese Materia Medica 2011;36(8):1004-1006
OBJECTIVETo develop a new method to rapidly determine and identify Guizhi Fuling capsule by portable acousto-optic tunable filter-near infrared spectroscopy.
METHODThe qualitative model was set up using principal component analysis. The correlation models between the NIR spectra and the reference values of five major constituents were obtained with partial least squares method.
RESULTThe identifying model accurately identified Guizhi Fuling capsule, and quantitative analytical models could precisely predicted the content of ellagic acid, baicalin, benzoylpaenoniflorin, cinnamaldehyde, and paeonol. The correlation coefficients of the calibration models were 0.924 2, 0.938 4, 0.924 2, 0.933 6, 0.934 7, the validation set coefficients of the calibration were 0.924 2, 0.938 4, 0.924 2, 0.933 6, 0.934 7, and the RMSEP were 1.138%, 3.014%, 0.751%, 0.625%, 3.455%, 1.363%, respectively. The results of external validation showed no significant difference between the predictive and the determining values by t-test.
CONCLUSIONThe method is accurate, rapid and non-destructive, and can be used for determining and identifying Guizhi Fuling capsule.
Acetophenones ; analysis ; Acrolein ; analogs & derivatives ; analysis ; Calibration ; Capsules ; chemistry ; Drug Evaluation ; methods ; Drugs, Chinese Herbal ; analysis ; Ellagic Acid ; analysis ; Flavonoids ; analysis ; Least-Squares Analysis ; Models, Chemical ; Principal Component Analysis ; methods ; Spectroscopy, Near-Infrared ; methods
4.Light chain deposition disease after renal transplantation: a report of 2 cases and a review of literature
Chenfeng JIAO ; Feng XU ; Xuefeng NI ; Jinsong CHEN ; Bing YOU ; Wei WANG ; Jiqiu WEN
Chinese Journal of Organ Transplantation 2020;41(1):37-41
Objective:To report for the first time the clinicopathologic characteristics of two patients with light chain deposition disease after renal transplantation.Methods:The clinicopathologic features were analyzed for two patients with light chain deposition disease and the related literature was reviewed.Case 1 was a 49-year-old male with unknown primary disease presenting with abnormal urine test and elevated serum creatinine at 24 months after kidney transplantation. Renal allograft biopsy hinted at light chain deposition disease. Case 2 was a 38-year-old male with light chain deposition disease in native kidneys presenting with proteinuria, microscopic hematuria and elevated serum creatinine at 15 months after kidney transplantation. Renal allograft biopsy supported recurrent light chain deposition disease.Results:1 case after bortezomib and dexamethasone dosing, serum creatinine decreased during follow-ups. 1 case received bortezomib and dexamethasone. However, sepsis and pulmonary infections developed and allograft function deteriorated.Conclusions:Light chain deposition disease after renal transplantation is a rare disorder with a rapid progression and a poor prognosis. Early detection of free light chain in blood and urine through immune fixed electrophoresis is conducive to an early diagnosis. The efficacy of bortezomib is to be furthered examined.
5.knocking out mediated by CRISPR-Cas9 genome editing for PD-L1 attenuation and enhanced antitumor immunity.
Huan DENG ; Songwei TAN ; Xueqin GAO ; Chenming ZOU ; Chenfeng XU ; Kun TU ; Qingle SONG ; Fengjuan FAN ; Wei HUANG ; Zhiping ZHANG
Acta Pharmaceutica Sinica B 2020;10(2):358-373
Blocking the programmed death-ligand 1 (PD-L1) on tumor cells with monoclonal antibody therapy has emerged as powerful weapon in cancer immunotherapy. However, only a minority of patients presented immune responses in clinical trials. To develop an alternative treatment method based on immune checkpoint blockade, we designed a novel and efficient CRISPR-Cas9 genome editing system delivered by cationic copolymer aPBAE to downregulate PD-L1 expression on tumor cells specifically knocking out Cyclin-dependent kinase 5 () gene . The expression of PD-L1 on tumor cells was significantly attenuated by knocking out , leading to effective tumor growth inhibition in murine melanoma and lung metastasis suppression in triple-negative breast cancer. Importantly, we demonstrated that aPBAE/Cas9-Cdk5 treatment elicited strong T cell-mediated immune responses in tumor microenvironment that the population of CD8 T cells was significantly increased while regulatory T cells (Tregs) was decreased. It may be the first case to exhibit direct PD-L1 downregulation CRISPR-Cas9 genome editing technology for cancer therapy. It will provide promising strategy for preclinical antitumor treatment through the combination of nanotechnology and genome engineering.