1.Study of the influence of uniform transverse magnetic field on the dose distribution of high energy electron beam using Monte Carlo method.
Shihu YOU ; Yun XU ; Zhangwen WU ; Qing HOU ; Chengjun GUO
Journal of Biomedical Engineering 2014;31(6):1350-1354
In the present work, Monte Carlo simulations were employed to study the characteristics of the dose distribution of high energy electron beam in the presence of uniform transverse magnetic field. The simulations carried out the transport processes of the 30 MeV electron beam in the homogeneous water phantom with different magnetic field. It was found that the dose distribution of the 30 MeV electron beam had changed significantly because of the magnetic field. The result showed that the range of the electron beam was decreased obviously and it formed a very high dose peak at the end of the range, and the ratio of maximum dose to the dose of the surface was greatly increased. The results of this study demonstrated that we could change the depth dose distribution of electron beam which is analogous to the heavy ion by modulating the energy of the electron and magnetic field. It means that using magnetic fields in conjunction with electron radiation therapy has great application prospect, but it also has brought new challenges for the research of dose algorithm.
Algorithms
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Electrons
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Humans
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Magnetic Fields
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Monte Carlo Method
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Phantoms, Imaging
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Radiation Dosage
2.Electrochemical Characterizations of Quaternarized Nanodiamond-Myoglobin Modified Electrode
Xiaoling MA ; Chengjun DING ; Pu ZHANG ; Wei GUO ; Hongxia LUO
Chinese Journal of Analytical Chemistry 2014;(9):1332-1337
Through a series of chemical reactions, a kind of quaternary ammonium salt derivative of nanodiamond, ND-CO-NH-CH2-CH2-N ( CH3 ) 3+· I-( QAS-ND ) , was obtained , which was confirmed by FTIR, element analysis experiment and the electrochemistry measurements. Mixed myoglobin ( Mb) and QAS-ND solution was dropped on the surface of the glassy carbon ( GC ) electrode to prepare QAS-ND/Mb/GC modified electrode. In 0. 1 mol/L phosphate buffer solution (PBS) (pH 7. 0), Mb in the membrane exhibited direct electrochemical properties and showed good stability. The electrocatalytic property of the modified electrode toward H2 O2 was investigated, the results showed that the modified electrode could be used as the H2O2 biosensor to achieve fast, accurate detection of H2O2, with a detection limit of 3. 5 mmol/L (S/N=3).
3.Content determination of tannin in Nodus Nelumbinis Rhizomatis
Shanxin LIU ; Lijing HOU ; Guangqian JIN ; Chengjun GUO ; Ruixue LIANG
China Journal of Traditional Chinese Medicine and Pharmacy 2005;0(02):-
Objective: To establish a method for the content determination of tannin in Nodus Nelumbinis Rhizomatis. Methods: The content of tannin in Nodus Nelumbinis Rhizomatis was detected by molybdophosphate colorimetric method. Results: The content of tannin in Nodus Nelumbinis Rhizomatis from different drugstores varied from 0.2537% to 1.637%. Conclusion: This method was simple, accurate and can be used for the quality control of Nodus Nelumbinis Rhizomatis.
4.Follow-up study on application of radiofrequency ablation combined with magnetic navigation assistance system in elderly patients with atrioventricular node reentrant tachycardia
Kang MENG ; Chengjun GUO ; Rui TIAN ; Huagang ZHU ; Dongping FANG ; Shuzheng LV ; Yundai CHEN
Chinese Journal of Geriatrics 2009;28(1):23-25
Objective To explore the safety, efficacy and 1-year follow-up outcome of radiofrequency ablation combined with magnetic navigation assistance system in elderly patients with atrioventricular node reentrant tachycardia (AVNRT). Methods Forty cases of patients with AVNRT identified by the electrophysiological test were enrolled in the study. Twenty cases were ablated with magnetic navigation system. The other 20 cases underwent the conventional catheters operation. With the cardiodrive, the 8 Frablation magnetic Helios I (Stereotaxis Inc, USA) was advanced to the Koch triangle area from the inferior caval vein (IVC). With the assistance of magnetic navigation (AXIOM Artis, Siemens, Germany), the direction of tip and the advancement or retraction of the catheters were regulated. The success rate, the time of procedure, the fluoroscopy time and the 1-year follow-up outcome were analyzed, and the complications of procedure were recorded. Results Forty cases with AVNRT underwent radiofrequency ablation successfully. In magnetic navigation group, 19/20 cases underwent magnetic catheter operation. The cases who failed to finish magnetic catheter operation underwent successfully conventional catheter operation. There was no perforation complication and no significant statistic difference in the success rate between two groups. No recurring case was found in the two groups 1 year later. The total of fluoroscopy time in magnetic navigation group was more than that in standard ablation group [(16.4±2.7) min vs. (11.1±1.0)rain, P<0.01], but the decreasing trend of fluoroscopy time in magnetic navigation group was showed. The operator's fluoroscopy time in magnetic navigation group was obviously less than that in standard ablation group [(4.5±0.6) min vs. (11.1±1.0) min, P<0.01]. Conclusions The radiofrequeney ablation combining with magnetic navigation system has the similar safety and efficacy to the conventional ablation in elderly patients with AVNRT, but the operator's fluoroscopy time was significantly decreased.
5.Comparison of drug eluting stent for treatment of intrastent restenosis and de novo lesion
Weiwei ZHU ; Chengjun GUO ; Xianliang LIU ; Hongyong SONG ; Guanqiao DING ; Lin ZHAO
Chinese Journal of Interventional Cardiology 2014;(3):158-162
Objective Compare the efifcacy and safety of drug eluting stent (DES) for treatment of in stent restenosis (ISR) and coronary de novo lesions. Methods Patients treated with DES for ISR and de novo lesions in Beijing Anzhen Hospital between October 2008 and December 2011 were followed up for 1 year. All lesions were divided into ISR and de novo group. Major adverse cardiovascular events (MACE) including all-cause death, myocardial infarction (MI) and clinical target lesion revascularization (TLR) were the primary endpoints. Results The study population consisted of 204 patients in the ISR group and 494 patients in the de novo group. Baseline clinical and angiographic parameters were comparable between the two groups. The rate of diabetic was higher in the ISR group than that in the de novo group (36.6%to 27.1%, P < 0.05). The diameter of coronary artery was smaller in the ISR group than that in the de novo group (2.72±0.36 to 3.08±0.54, P<0.01). The rate of TLR in the ISR group was higher than that in the de novo group (10.7%to 17.2%, P<0.05;14.2%to 21.1%, P<0.05),contributing to higher MACE in ISR group. Conclusions DES implantation is safe and effective for treatment of ISR lesions, but the rate of TLR is higher compared to treatment of de novo lesions.
6.Study of the feasibility and precision in dose calculation with the method of bulk density assignment
Songbing QIN ; Juying ZHOU ; Wei GONG ; Chengjun WU ; Jian GUO ; Long CHENG ; Wei ZHAN
Chinese Journal of Radiation Oncology 2013;(3):247-249
Objective To study investigate the dose accuracy that can be achieved with the method of bulk density assignment.Methods Sixteen cases of nasopharyngeal cancer patients and nineteen cases of esophageal cancer patients who accept radiotherapy in our department were selected.The planning CT images with bulk density assignment to different classes of tissues were applied to calculate the dose distributions,and then the resulting dose volume histograms (DVH) of the tumor and organs of risk were compared with the original treatment plan.The paired t-test was taken for dose comparison between two plans.Results The DVH comparison based on the planning CT and the bulk density assignment CT showed good agreements.With nasopharyngeal cancer patients,differences between the two plans about target and normal tissue were less than 1%.With esophageal cancer patients,the dose differences were less than 2%.Conclusion Preliminary results confirm that the bulk density assignment method can be applied to calculate the dose distributions.
7.Expressions of Mast Cell Tryptase and Brain Natriuretic Peptide in Myocardium of Sudden Death due to Hypersensitivity and Coronary Atherosclerotic Heart Disease
Jieru SHI ; Chengjun TIAN ; Qiang ZENG ; Xiangjie GUO ; Jian LU ; Cairong GAO
Journal of Forensic Medicine 2016;32(3):161-164
Objective To explore the value of mast cell tryptase and brain natriuretic peptide(BNP)in the differential diagnostic of sudden death due to hypersensitivity and coronary atherosclerotic heart dis-ease.Methods Totally 30 myocardial samples were collected from the autopsy cases in the Department of Forensic Pathology, Shanxi Medical University during 2010—2015. All samples were divided into three groups:death of craniocerebral injury group, sudden death of hypersensitivity group and sudden death of coronary atherosclerotic heart disease group, 10 cases in each group. Mast cell tryptase and BNP in myocardium were detected by immunofluorescence staining and Western Blotting.Results Immunofluo-rescence staining showed that the positive staining mast cell tryptase appeared in myocardium of sudden death of hypersensitivity group and coronary atherosclerotic heart disease group. Among the three groups, the expression of mast cell tryptase showed significantly differences through pairwise comparison(P<0.05); The expression level of BNP in sudden death of coronary atherosclerotic heart disease group were significantly higher than the sudden death of hypersensitivity group and death of craniocerebral injury group(P<0.05). The difference of the expression level of BNP between the sudden death of hypersensitivity group and the death of craniocerebral injury group had no statistical significance(P>0.05).Conclusion The combined detection of the mast cell tryptase and BNP in myocardium is expected to provide help for the forensic differential diagnosis of sudden death due to hypersensitivity and coronary atherosclerotic heart disease.
8.Ultrasound-mediated destruction of gene-loaded microbubbles enhanced the transfection of phospholamban antisense RNA into cardiac myocytes
Guozhong WANG ; Jinghua LIU ; Shuzheng Lü ; Chengjun GUO ; Yingchuan ZHANG ; Fei YUAN ; Xiantao SONG ; Yuan ZHOU ; Changjiang GE
Chinese Journal of Ultrasonography 2010;19(10):897-900
Objective To explore whether ultrasound-mediated microbubbles destruction could enhance anti-sense RNA transfection and expression. Methods Phospholamban antisense RNA eukaryon vector PcDNA 4. 1-asPLB was successfully constructed and it was transfected into cardiac myocytes by various methods including calcium phosphate precipitation, ultrasound exposure and ultrasound-mediated microbubbles destruction. The expression of PLB and sarcoplasmic retculum Ca2+ ATPase (SERCA2a) in cardiac myocytes was tested by RT-PCR and western blot. Results The transfection and expression of PcDNA 4. 1-asPLB increased significantly in cells treated with ultrasound-mediated microbubbles destruction compared to other transfer groups( P <0.05). The expression of PLB was inhibited specifically after cardiac myocytes were transfected with PcDNA 4. 1-asPLB. There was no change of PLB expression after cardiac myocytes transfected with PcDNA 4. 1 ( P <0.05). Though the expression of SERCA2a never exhibited any changes after PcDNA 4. 1-asPLB transfection, the PLB/SERCA2a ratio decreased markedly. Conclusions As a highly effective antisense RNA transfer method, ultrasound-mediated microbubbles destruction can enhance the transfection and expression of the PcDNA 4. 1-asPLB significantly. The PcDNA4. 1-asPLB transfection inhibits the expression of PLB and result in decrease of PLB/SERCA2a ratio in cardiac myocytes.
9.Prevalence of depressive and anxiety disorders in cardiovascular outpatients from 14 tertiary general hospitals of 5 Chinese cities.
Guo LI ; Ronghuan JIANG ; Chengjun GUO ; Meiyan LIU ; Lijun ZHANG
Chinese Journal of Cardiology 2014;42(12):1035-1038
OBJECTIVETo explore the prevalence of depression and (or) anxiety disorders among cardiovascular outpatients of tertiary general hospitals of five Chinese cities.
METHODSA hospital-based cross-sectional survey was conducted in the cardiovascular out-patient departments of 14 tertiary general hospitals in five Chinese cities. The patients aged 18 years and over were recruited consecutively, who were conscious and with informed consent, and can finish the questionnaire independently. All the subjects were screened with Hospital Anxiety Depression Scale (HADS). The subjects with HADS score of 8 and over were interviewed and diagnosed by psychiatrists using mini international neuropsychiatric interview (MINI). The physicians made the diagnosis and management without knowing the results of MINI and HADS score. Subjects who refused MINI were defined as the case of loss of follow-up.
RESULTSA total 2 123 subjects were included in the survey. The adjusted prevalence rate of depressive and anxiety disorder was 4.05% (86/2 123), the depressive and/or anxiety disorder was 14.27 % (303/2 123), depressive and anxiety disorder and mixed depressive or anxiety disorder was 14.37% (305/2 123) according to MINI. The adjusted prevalence of lifetime depressive and anxiety disorder was 5.37% (114/2 123), depressive and/or anxiety disorder was 16.91% (359/2 123), depressive and anxiety disorder and mixed depressive-anxiety disorder was 17.00% (361/2 123).
CONCLUSIONThere is a high prevalence of depressive and anxiety disorder among cardiovascular outpatients from tertiary general hospitals in China. Therefore, doctors must pay attention to this disorder and try to reduce the impact of this disorder in cardiovascular patients.
Adult ; Anxiety Disorders ; epidemiology ; Asian Continental Ancestry Group ; Cardiovascular Diseases ; psychology ; China ; epidemiology ; Cities ; Cross-Sectional Studies ; Depressive Disorder ; epidemiology ; Disease Management ; Hospitals ; Hospitals, General ; Humans ; Outpatients ; Physicians ; Prevalence ; Surveys and Questionnaires
10.Effect of Fuzhenghuayu compound on hepatocyte expression of Nrf2 in a mouse model of hepatic fibrosis.
Shuo WU ; Xingbin MA ; Chengjun ZHOU ; Jingjie ZHAO ; Jianqiang GUO ; Weihua XU
Chinese Journal of Hepatology 2014;22(8):609-615
OBJECTIVETo investigate the effect of Fuzhenghuayu compound (FZHc) on expression of nuclear factor E2-related factor 2 (Nrf2) in hepatocytes under conditions of hepatic fibrosis using a mouse model.
METHODSMice were randomly assigned to a control group and a hepatic fibrosis model group. The control group was further divided into three subgroups for use as normal controls (A1), mineral oil-treated controls (A2), and FZHc-treated controls (A3); the hepatic fibrosis model group was administered carbon tetrachloride (CC14 dissolved in mineral oil and injected intraperitoneally) and further divided into four subgroups for use as 6-weeks models (B1), 10-weeks models (B2), low-dose (L)-FZHc models (C1), and high-dose (H)-FZHc models (C2). The FZHc (capsule powder diluted with double-distilled water to 0.1 g/mL) was administered via gastric perfusion to groups A3, C1, and C2 starting at week 7 of the experiment. At the end of week 6 and 10, hepatic specimens were collected and evaluated for degree of hepatic fibrosis and inflammation using routine haematoxylin-eosin staining and Masson staining. Immunohistochemical analysis was performed to measure the hepatocyte expression of Nrf2, NAD(P)H quinine oxidoreductase 1 (Nqol), a-smooth muscle actin (a-SMA) and fibronectin (FN). Real-time fluorescence quantitative PCR was used to measure Nrf2 mRNA expression. Western blotting was used to detect Nrf2 and Nqol total protein expression and Nrf2 nuclear translocation. F test, LSD test and ridit test were used for statistical analyses.
RESULTSCompared with the B2 group (ridit value: 0.09), the model groups treated with FZHc showed significantly lower degrees of hepatic inflammation and fibrosis for both the low (C1 group, ridit value: 0.32) and high doses (C2 group, ridit value: 0.40) (F =82.927, P less than 0.05). In addition, compared with the B2 group, the model groups treated with FZHc showed significantly decreased expression of a-SMA and FN proteins, with a dose-dependent trend (by immunohistochemistry: C 1 group at the end of 10 weeks, F =77.421, 118.262, P less than 0.05; C2 group, P =0.002, 0.013) and significantly increased expression of Nrf2 and Nqol proteins (by immunohistochemistry:C1 and C2 groups at the end of 10 weeks, F =182.537, 75.615, P less than 0.05 and by westen blotting: F =45.664, 127.673, P less than 0.05), which also showed a dose-dependent trend (C2 group, P =0.000, 0.014; 0.005, 0.014). Western blotting also indicated that the amount of nuclear transported Nrf2 was higher in the C1 and C2 groups at the end of 10 weeks (vs. B2 group, F =94.787, P less than 0.05), and the amount of nuclear transported Nrf2 was significantly higher in the C2 group (vs. C1 group, P =0.044). Nrf2 mRNA expression was significantly higher in the C1 group than in the B2 group (F =3230.105, P less than 0.05), and the C2 group had more substantially increased expression (P =0.001); there was no statistical difference found between groups B1 and B2 (P =0.094).
CONCLUSIONFuzhenghuayu compound increased the expression of Nrf2 mRNA and protein under conditions of hepatic fibrosis in mice and stimulated Nrf2 nuclear transport, as well as increased expression of the Nrf2 target gene Nqol that is known to suppress activation of hepatic stellate cells and decrease the deposition of FN. Therefore, Fuzhenghuayu compound may ameliorate hepatocyte injury in hepatic fibrosis in mice by exerting an antihepatic fibrosis effect.
Animals ; Drugs, Chinese Herbal ; pharmacology ; Female ; Hepatocytes ; drug effects ; metabolism ; Liver Cirrhosis, Experimental ; metabolism ; Mice ; Mice, Inbred Strains ; NAD(P)H Dehydrogenase (Quinone) ; metabolism ; NF-E2-Related Factor 2 ; metabolism