1.The basic structure of heavy-ion tumor therapy facility.
Tong WANG ; Ping XIAO ; Shaowei JIA ; Kehong YUAN ; Hongjie YANG
Chinese Journal of Medical Instrumentation 2014;38(6):427-438
Heavy-ions have the similar characteristic of depth-dose distribution with protons, but exhibit enhanced physical and radiobiological benefits. With increasing development in technical and clinical research, more facilities are being installed in the world. At the same time, many critical techniques of heavy-ion therapy facility were optimized and completed. This paper classified and reviewed the basic structure of heavy-ion system equipments, especially the accelerator, gantry, nozzle , TPS.
Cancer Care Facilities
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Heavy Ion Radiotherapy
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instrumentation
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Humans
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Neoplasms
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therapy
2.An Experimental Study of CAIMA in Vitro
Jun YANG ; Kehong ZHANG ; Peikun GU ; Zhengjun JIN
Academic Journal of Second Military Medical University 1982;0(01):-
To study the mechanism of CAIMA (Computer assisted instant monitoring drug administration), atracurium, a new non - depolarizing muscle relaxant was used in isolated rat diaphragm. The doses and administration rate were precisely controlled by using an improved flowing-bath system. The results showed that with increasing drug concentration, onset time shortened,over-shoot time prolonged, initial recovery rate reduced and onset rate, over-shoot extent and recovery index increased. The over-shoot existed at any pharmacologically effective concentrations and it was positively correlated to drug concentration. As a result of need-dependent and intermittent (pulsatil) drug administration, one maximally profited effect from over-shoot, that is, the effect could be maintained with over-shoot at the administration interval. Hence, the total dose could be dramatically reduced. Furthermore, for a given effect, it needs lower drug concentration with CAIMA than with classical methods and so the effect was nuch more stable.
3.Protection and mechanism of notoginsenoside-Rg_1 on focal cerebral ischemia-reperfusion rats
Lanou WU ; Heqin ZHAN ; Junling YAN ; Wenfeng CAI ; Jinping WU ; Kehong YANG
Chinese Traditional and Herbal Drugs 1994;0(02):-
Objective To explore the effects of notoginsenoside-Rg_1 on brain-derived neurotrophic factor(BDNF) protein in cerebrum cortex of MCAO/R injury,as well as to investigate whether notoginsenoside-Rg_1 can up-regulate the protein content of BDNF of the positive neurons or the amount of the po-sitive neurons.Methods Adult male SD rats(60) were randomly divided into model group,notoginsenoside-Rg_1 high,middle,and low dose(200,100,50 mg/kg) groups,and the positive control(Nimodipine,1 mg/kg) group.All drugs were given once a day by ip till the mouse was killed.The focal cerebral(ischemia-)reperfusion model was made with thread-occluded method.Their frozen brain tissue were sliced(into) section of 12 ?m thickness.The four rats were randomly taken from each groups to be treated as specimens after surgical handle in 1,3,and 7 d.The slices were according to the immunohistochemical ABC techniques.The protein content of BDNF of the positive neurons and the amount of the positive neurons in cerebrum cortex of rat were observed and counted by HPIAS—1000 analytic system,and the nervous deficit symptoms after the cerebral ischemia were observed.Results Comparing with the model group,all notoginsenoside-Rg_1 treated groups obviously improved some nervous deficit symptoms of cerebral ischemia-reperfusion rats,and increased the protein content of BDNF and the amount of the positive neurons in the cerebrum cortex of model rats(P
4.Comparative Study on Four Polyphyllins Content in Paridis Rhizome and Fibril
Fang YE ; Pei HU ; Guangyi YANG ; Chenning ZHANG ; Jinbao WEI ; Liangxue SUN ; Kehong CAO
China Pharmacist 2015;18(12):2073-2075,2122
Objective:To investigate the distribution of four polyphyllins in different parts of paris polyphylla by means of compa-ring the contents of relative constituents in paridis rhizome and fibril to provide reference for comprehensive exploitation and utilization of paris polyphylla. Methods:Paris polyphylla samples were collected from Wudang mountain area and Shennongjia forest area. The contents of main secondary metabolites including polyphillinⅠ,Ⅱ,Ⅵ andⅦin paridis rhizome and fibril were evaluated by HPLC. Results:The four polyphyllins contents had obvious differences in different parts of polyphylla. The total content of four polyphillins in fibril was significantly higher than that in rhizome. Diosgenin compositions had no significant difference in the two parts, and the con-tents of pennogenin compositions in fibril showed significantly higher than those in rhizome. Conclusion:As for the main chemical com-positions contained in polyphylla, there is chemistry equality between fibril and rhizome, thus both of them can be used for medicine. However, as for the contents of four steroidal saponins, the distribution of secondary metabolites has obvious difference between fibril and rhizome, and the result may be caused by steroidal saponins transferred to rhizome for storage after the synthesis in fibril.
5.Molecular mechanism of different sensitivities of PML-RARα to apoptosis induced by apoptosis inducing agents
Haitao ZHAO ; Peie WEN ; Xia REN ; Weihua YANG ; Hua FAN ; Gaojuan QIAO ; Tianhua TANG ; Haiquan REN ; Kehong BI ; Guosheng JIANG
Journal of International Oncology 2009;36(5):394-397
Objective To study the molecular mechanism of different sensitivities to apoptosis induced by low concentration of As2O3 in PML-RARα negative HL-60 cells and PML-RARα positive NB4 cells. Meth-ods NB4 and HL-60 cells were cultured with As2O3 for 1 to 4 days; cell proliferation were detected by MTT method; the apoptosis was detected by flow cytometry,Bcl-2,Bax and Fas mRNA were determined by RT-PCR. Results The proliferation of NB4 cells was inhibited obviously by As2O3(1.0 μmol/L)with the induction of apoptosis( P <0.05) ,which was accompanied by the down-regulation of Bcl-2 mRNA expression( P <0.05)and the ratio of Bcl-2/Bax(P <0.05), but there was no obvious variation of Bax and Fas expression( P >0.05). Inhibition of proliferation and apoptosis were not obvious in PML-RARα negative HL-60 cells induced by low concentration As2O3 ( P >0.05), and there was no obvious variation of Bcl-2, Bax, Fas mRNA expres-sion or Bcl/Bax ratio( P >0.05). Conclusion The ratio of Bcl-2/Bax is contributed to the different sensitiv-ities of PML-RARα negative HL-60 cells and positive NB4 cells induced by low concentration of As2O3.
6.Pumping performance of a new piezoelectric pump for drug delivery.
Junwu KAN ; Zhigang YANG ; Kehong TANG ; Guangming CHENG
Journal of Biomedical Engineering 2004;21(2):297-301
A novel double-chamber series piezoelectric pump has been presented and tested. The pump is a multi-layer circular planar structure, consisting of PMMA (polymethyl methacrylate) pump body, two PZT actuator membranes and three cantilever valves. The PZT actuators are driven at a phase difference of 180 degrees, which is equal to two one-chamber pumps running in series. The output performance depends on the geometrical parameters of the actuator membrane. The prototype pump, fabricated with the PZT membrane 0.18 mm in thickness and 50 mm in diameter of 50 mm, can deliver drug in either direct way (pumping liquid drug) or indirect way (pumping air to extrude liquid drug from a sealed container). The frequency-response characteristic of the two handling methods is of difference. The pump obtains optimum performance at low frequency for liquid as medium, and at high frequency for air as medium. For both the direct delivery and indirect delivery, the maximum flowrate achieved reached up to 220 ml/min and 35 ml/min, respectively; and the maximum backpressure obtained amounted to about 14 KPa and 21 KPa, respectively, at the applied voltage of 80 V with frequency of 20 Hz.
Drug Delivery Systems
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instrumentation
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Electricity
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Equipment Design
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Evaluation Studies as Topic
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Insulin Infusion Systems
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Models, Theoretical
7.Adenosine deaminase acting on RNA-1 regulates the radiosensitivity of lung adenocarcinoma cells
Cai CHEN ; Wendi YANG ; Kehong CHEN ; Yaqian ZHANG ; Hong ZENG ; Yuan PENG ; Xiaoyue ZHANG ; Zhenzhou YANG
Journal of Army Medical University 2024;46(12):1378-1386
Objective To investigate the effect of down-regulating adenosine deaminase acting on RNA-1(AD AR1)on the radiosensitivity of lung adenocarcinoma cells.Methods Lentiviral transfection was used to establish an ADAR1 knockdown cell line based on A549 cells.Then the cells were divided into negative control(shNC)and ADAR1 knockdown(shADAR1)groups,which were followed by a single-dose irradiation of 0 Gy and 6 Gy X-rays.Western blotting and RT-PCR were utilized to detect the expression of AD AR1 at protein and mRNA levels,respectively.CCK-8 assay,wound healing assay and Transwell migration assay were applied to measure cell proliferation and migration abilities.Meanwhile,clone formation assay was performed to detect the effect of down-regulating ADAR1 on the radiosensitivity of A549 cells.Flow cytometry and Western blotting were conducted to detect the expression levels of apoptosis and apoptosis-related proteins Bax and Bcl-2.Immunofluorescence assay and Western blotting were used to detect the expression level of γ-H2AX.Comet assay was performed to detect the level of cellular DNA damage.Twelve female nude mice(4~6 weeks old,weighing 16~18 g)were divided into shNC group,shADAR1 group,shNC+ionizing radiation(IR)group and shADAR1+IR group,with 3 mice in each group.The growth of tumor of different groups was observed with subcutaneous tumorigenesis assay.Results Western blotting and RT-qPCR showed that the protein and mRNA expression of ADAR1 were significantly reduced in A549 shADAR1 cells(P<0.05).CCK-8 assay,wound healing assay and Transwell migration assay indicated that down-regulation of ADAR 1 inhibited the proliferation and migration abilities of A549 cells,and this inhibition trend became more obvious(P<0.01)after IR.Cell clone formation assay showed that the clone formation rate of both groups was decreased,with the increase of radiation dose.But the number of formed clones was lower in the shADAR1 group than the shNC group.Flow cytometry and Western blotting displayed that down-regulation of AD AR1 increased the apoptotic rate and Bax expression in A549 cells(P<0.01)and decreased Bcl-2 expression(P<0.05),and the apoptotic rate and Bax protein level were further increased in A549 shADAR1 cells after IR(P<0.01),and the Bcl-2 protein level was further decreased(P<0.01).The number of γ-H2AX foci and protein level in A549 shADAR1 cells were significantly increased after IR(P<0.05),and the results of comet assay showed that the DNA damage was more obvious in A549 shADAR1 cells after IR(P<0.01).Subcutaneous tumorigenesis assay in nude mice showed that the growth of subcutaneous tumour of A549 shADAR1 cells was significantly inhibited after IR(P<0.01).Conclusion Down-regulation of ADAR1 significantly inhibits the proliferation and migration of A549 cells after IR and promotes apoptosis and DNA damage,and thereby increases the radiosensitivity of lung adenocarcinoma cells.
8.Effect of low-molecular-weight heparin combined with doxorubicin on hepatocellular cancer cell migration in vitro.
Kehong YANG ; Linyan MA ; Xiu CHENG ; Chao CHEN ; Mengxiao ZHANG ; Hao LIU ; Zhiwen JIANG
Journal of Southern Medical University 2014;34(7):1048-1052
OBJECTIVETo investigate the anti-cancer effect of low-molecular-weight heparin (LMWH) combined with doxorubicin and explore the mechanism.
METHODSHepatocellular cancer HepG2 cells exposed to LMWH, doxorubicin, or both were evaluated for cell viability with MTT assay and for changes in their migration ability using wound healing assay and Transwell migration assay. The changes in cellular expressions of matrix metalloproteinase-9 (MMP-9) and MMP-2 mRNA and proteins were analyzed with quantitative real-time PCR (qRT-PCR) and Western blotting, and ELISA was used to determine heparanase (HPA) concentration in the cell culture medium.
RESULTSHepG2 cells exhibited suppressed proliferation in response to LMWH and doxorubicin treatments. The combined treatment caused a significantly higher inhibition rate of cell migration than LMWH and doxorubicin alone. LMWH enhanced doxorubicin-induced down-regulation of MMP-9, MMP-2 and HPA in the cells.
CONCLUSIONSLMWH can enhance the inhibitory effect of doxorubicin on the migration of HepG2 cells, the mechanism of which may involve the down-regulation of MMP-9, MMP-2 and HPA expressions.
Cell Movement ; drug effects ; Cell Survival ; Down-Regulation ; Doxorubicin ; pharmacology ; Glucuronidase ; chemistry ; Hep G2 Cells ; Heparin, Low-Molecular-Weight ; pharmacology ; Humans ; Liver Neoplasms ; pathology ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Neoplasm Invasiveness ; RNA, Messenger ; Real-Time Polymerase Chain Reaction
9.Observation on the teaching effect of mind mapping on interns in nephrology department
Lei FENG ; Ping LI ; Jie YANG ; Jin XIE ; Fang YOU ; Min LI ; Kehong CHEN
Chinese Journal of Medical Education Research 2023;22(3):403-408
Objective:To improve the critical thinking ability of interns in nephrology department based on electronic "Spot" mind mapping teaching method.Methods:In the control group, the traditional clinical teaching method was adopted. Each kidney disease unit was divided into 3 courses. ①The clinical practice teacher dictated or demonstrated his/her experience to the student in the first class. ②Students could exchange questions and answers in the second class. ③In the third class, according to the homework situation, the teacher presided over the discussion, guided the students to express their difficulties and help them solve the problems. The research group adopted the electronic "Spot" mind mapping teaching method: ①Grouping: the students were divided into groups, 6 to 8 people in each group, a total of 16 groups. ②Preparation: each group established a WeChat group, and teachers guided them download the Mindmanager software and learn its mapping method. ③In class: each kidney disease unit was divided into 3 sessions. In the first class, based on what the instructor taught, the students summarized the contents and drew a mind map, and then explain their understanding according to the map. In the second class, "Spot" in the group was conducted based on standards, reading each other in the group, actively discussing with each other, further improving and reconstructing the core knowledge points of the chapter, and encouraging each student to actively participate in enhancing their subjective initiative in learning. In the third class, teachers evaluated students according to their learning situation, and students filled in the gaps according to their opinions, perfected their mind maps, and finally posted to the WeChat group. ④Review: the final versions were sent to the WeChat groups as review materials, which was convenient for learning together. SPSS 24.0 was used for Chi-square test.Results:There was no significant difference between the two groups before study ( P>0.005). After the research, the scores of theory test ( t=2.52, P=0.015), clinical skill test ( t=2.22, P=0.034) and total score ( t=3.53, P=0.003) in the experimental group were significantly higher than those in the control group ( P<0.05). There was no significant difference in the scores of critical thinking ability between the two groups before research ( P>0.05). Six months after research, the total scores of critical thinking ability in the experimental group were significantly higher than those in the control group ( P<0.05). Conclusion:The introduction of electronic "Spot" mind mapping teaching method into clinical practice teaching can realize the cross-linking of related knowledge points and systematize the knowledge. At the same time, it is interesting and can stimulate students' learning interest, and is helpful to cultivate the clinical critical thinking ability of students.
10.Effect of low-molecular-weight heparin combined with doxorubicin on hepatocellular cancer cell migration in vitro
Kehong YANG ; Linyan MA ; Xiu CHENG ; Chao CHEN ; Mengxiao ZHANG ; Hao LIU ; Zhiwen JIANG
Journal of Southern Medical University 2014;(7):1048-1052
Objective To investigate the anti- cancer effect of low- molecular- weight heparin (LMWH) combined with doxorubicin and explore the mechanism. Methods Hepatocellular cancer HepG2 cells exposed to LMWH, doxorubicin, or both were evaluated for cell viability with MTT assay and for changes in their migration ability using wound healing assay and Transwell migration assay. The changes in cellular expressions of matrix metalloproteinase-9 (MMP-9) and MMP-2 mRNA and proteins were analyzed with quantitative real-time PCR (qRT-PCR) and Western blotting, and ELISA was used to determine heparanase (HPA) concentration in the cell culture medium. Results HepG2 cells exhibited suppressed proliferation in response to LMWH and doxorubicin treatments. The combined treatment caused a significantly higher inhibition rate of cell migration than LMWH and doxorubicin alone. LMWH enhanced doxorubicin-induced down-regulation of MMP-9, MMP-2 and HPA in the cells. Conclusion LMWH can enhance the inhibitory effect of doxorubicin on the migration of HepG2 cells, the mechanism of which may involve the down-regulation of MMP-9, MMP-2 and HPA expressions.