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.A fitted formula for calculating electron beams mean energy in the homogeneous water phantom.
Shuzhi ZHANG ; Lele LIU ; Yun XU ; Zhangwen WU ; Qing HOU ; Anjian XU ; Chengjun GOU
Journal of Biomedical Engineering 2014;31(3):516-542
The hybrid pencil beam model (HPBM) is an effective algorithm for calculating electron dose distribution in radiotherapy. The mean energy distribution of incident electron beam in phantom is one of the factors that affect the calculation accuracy of HPBM, especially in field edge areas near the end of the electron range. A new fitted formula based on Monte Carlo (MC) simulation data for electron beams with energy range of 6-20 MeV in the homogeneous water phantom is proposed in this paper. The precision of the fitted formula within the scope of the energy was evaluated by comparing the electron dose distribution of ECWG measured data with that obtained from HPBM which took the mean electron energy that calculated by the fitted formula and the existed empirical formula, respectively. The results showed that the accuracy of dose distribution that obtained by the mean electron energy calculated with the fitted formula increased about 1%.
Algorithms
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Electrons
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Humans
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Monte Carlo Method
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Phantoms, Imaging
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Radiotherapy Planning, Computer-Assisted
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Water
3.Evaluation of genetic diversity and population structure of Bletilla striata based on SRAP markers.
Yu-long SUN ; Bei-wei HOU ; Li-xia GENG ; Zhi-tao NIU ; Wen-jin YAN ; Qing-yun XUE ; Xiao-yu DING
Acta Pharmaceutica Sinica 2016;51(1):147-152
Bletilla striata has been used as traditional Chinese medicine for several centuries. In recent years, the quality and quantity of wild B. striata plants have declined sharply due to habitat deterioration and human over-exploitation. Therefore, it is of great urgency to evaluate and protect B. striata wild plant resource. In this study, sequence-related amplified polymorphism (SRAP) markers were applied to assess the level and pattern of genetic diversity in twelve populations of B. striata. The results showed a high level of genetic diversity (PPB = 90.48%, H = 0.349 4, I = 0.509 6) and moderate genetic differentiation among populations (G(st) = 0.260 9). Based on the unweighted pair-group method with arithmetic average (UPGMA), twelve populations gathered in three clusters. The cluster 1 included four populations. There are Nanjing, Zhenjiang, Xuancheng and Hangzhou. The seven populations which come from Hubei Province, Hunan Province, Jiangxi Province and Guizhou Province belonged to the cluster 2. The cluster 3 only contained Wenshan population. Moreover, Mantel test revealed significant positive correlation between genetic distances and geographic distances (r = 0.632 9; P < 0.000 1). According to the results, we proposed a series of conservation consideration for B. striata.
China
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Genetic Markers
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Genetic Variation
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Genetics, Population
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Orchidaceae
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genetics
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Phylogeny
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Plants, Medicinal
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genetics
4.Comparison of adenosine stress and dobutamine stress by real-time myocardial contrast echocardiography in detecting myocardium ischemia in dogs.
Yan-qiu XING ; Bo-wen HOU ; Yun ZHANG ; Xiang-qun LIU ; Hai-qing GAO
Chinese Medical Journal 2009;122(17):2002-2007
BACKGROUNDReal-time perfusion imaging (RTPI) using ultrasound contrast agents has shown good "accuracy" in detecting myocardial infarction, however its accuracy in the assessment of peri-infarct ischemia and stress echocardiography are not known. The aim of this study was to determine the accuracy of RTPI in assessment of peri-infarct ischemia during dobutamine and adenosine stress.
METHODSWe employed the RTPI modality (Agilent and ATL Philips) in a canine model (18 dogs) of distal coronary occlusion and proximal coronary stenosis. Using coronary flow probe recordings, the physiologic significance of proximal coronary stenosis was established by confirming abolition of the coronary reserve. The contrast agent Optison was given as a slow bolus injection at baseline, during prolonged distal coronary occlusion, during adenosine bolus stress and during dobutamine stress. Triphenyltetrazolium chloride (TTC) staining was used to verify a distal infarction. RTPI recordings at baseline, the distal coronary occlusion and stress protocols were randomly mixed and reviewed blindly.
RESULTSIn all but one dog, RTPI detected a distal infarct as small as 9% of the left ventricle. The sensitivity, specificity and overall diagnostic accuracy of RTPI in the detection of distal infarcts were: 94%, 89% and 92%, respectively. The sensitivity, specificity, and overall diagnostic accuracy of RTPI in the assessment of peri-infarction ischemia were 83%, 92% and 88% for adenosine stress and 95%, 86% and 91% for dobutamine stress, respectively.
CONCLUSIONSEven small distal infarcts can be detected by RTPI; peri-infarct ischemia can be accurately recognized by RTPI during stress; adenosine and dobutamine stress appear equally reliable in the RTPI evaluation of peri-infarct ischemia.
Adenosine ; toxicity ; Animals ; Coronary Circulation ; drug effects ; Dobutamine ; toxicity ; Dogs ; Echocardiography ; methods ; Female ; Hemodynamics ; drug effects ; Male ; Myocardial Infarction ; diagnostic imaging
5.Chemical constituents from Alyxia sinensis (II).
Gang-li WANG ; Hua YAN ; Qing-yun HOU ; Yang LU ; Ning-bo GONG ; Rui-chao LIN
China Journal of Chinese Materia Medica 2002;27(3):199-201
OBJECTIVETo demonstrate the chemical constituents of Alyxia sinensis.
METHODThe constituents were isolated by column chromatography and identified by advanced physical and spectral analysis.
RESULTEight compounds have been isolated and elucidated as bauereny acetate(18), scopletin(19), liriodendrin(20), pinoresinol-di-O-beta-D-glucopyranoside(21), daucosterol(22), flaxetin(23), esculin(24), aseculin(25).
CONCLUSIONThese compounds were found from the plant for the first time, and compound 20,21,23-25 were found from Alyxiae genis for the first time, and compound 18 is firstly been isolated from natural source.
Apocynaceae ; chemistry ; Esculin ; chemistry ; isolation & purification ; Furans ; chemistry ; isolation & purification ; Glucosides ; chemistry ; isolation & purification ; Molecular Structure ; Plants, Medicinal ; chemistry ; Triterpenes ; chemistry ; isolation & purification
6.Studies on the chemical constituents of the stems of Alyxia sinensis (I).
Gang-li WANG ; Qing-yun HOU ; Ji ZHANG ; Ji-min XU ; Ji-feng PENG ; Rui-chao LIN
China Journal of Chinese Materia Medica 2002;27(2):125-127
OBJECTIVETo demonstrate the chemical constituents of Alyxia sinensis.
METHODPhytochmical experiment was carried out, using column chromatograph technologies.
RESULTFive compounds have been isolated from the petroleum ether soluble part of the stems of A. sinensis. Their structures have been elucidated respectively as heptatriacontane(1), octatriacontane(2), 20-noatriacontannone(3), 20-nonatriacontanone(4), 20-tetraacontanoe(5), physcion(6), emodin(7), chrysophanol(8), coumarin(9), stigmasterol acetate(10), beta-sitosterol acetate(11), lupeol(12), betulin(13), stigmasterol(14), beta-sitosterol(15), ursolic acid(16), oleanolic acid(17).
CONCLUSIONAll these compounds are firstly been isolated from A. sinensis. And compound 5-9, 10, 11 are also been separated from Alyxiae genus for the first time.
Anthraquinones ; chemistry ; isolation & purification ; Apocynaceae ; chemistry ; Emodin ; analogs & derivatives ; chemistry ; isolation & purification ; Plant Stems ; chemistry ; Plants, Medicinal ; chemistry
7.Efficacy observation on female chronic pyelonephritis treated with abdominal cluster-needling therapy.
Jian-Yun HONG ; Fu LI ; Xiao-Qing LIANG ; Ze HOU
Chinese Acupuncture & Moxibustion 2013;33(4):303-305
OBJECTIVETo observe the difference in the clinical efficacy on female chronic pyelonephritis between abdominal cluster-needling therapy and western medicine so as to explore the optimal therapeutic method for the disease.
METHODSSeventy cases of female chronic pyelonephritis were randomized into an abdominal cluster-needling group and levofloxacin group, 35 cases in each one. In the abdominal cluster-needling group, the lower abdominal point was selected in combination with Zusanli (ST 36), Sanyinjiao (SP 6) and Taixi (KI 3). The treatment was given once a day and 10 treatments made one session. In the levofloxacin group, levofloxacin capsules were prescribed for oral administration, once a day. Three months later, the clinical efficacy was observed before and after treatment in two groups.
RESULTSThe curative rate was 65.7% (23/35) and the total effective rate was 100.0% (35/35) in the abdominal cluster-needling group. The curative rate was 22.9%, (8/35) and the total effective rate was 71.4% (25/35) in the levofloxacin group. The clinical efficacy in the abdominal cluster-needling group was superior to that in the levofloxacin group (P < 0.01, P < 0.05).
CONCLUSIONThe abdominal cluster-needling therapy achieves the significant efficacy on female chronic pyelonephritis and it is the optimal therapy for the disease.
Acupuncture Points ; Acupuncture Therapy ; Aged ; Chronic Disease ; therapy ; Female ; Humans ; Middle Aged ; Pyelonephritis ; therapy ; Treatment Outcome
8.Anticomplementary activity and constituents of Phyllanthus urinaria
Fang-Juan ZHU ; Ling-Li HOU ; Qian-Yun SUN ; Qing-Xiong YANG
Chinese Pharmacological Bulletin 2018;34(5):686-690
Aim To explore the anticomplementary ac-tivity and active constituents of Phyllanthus urinaria. Methods Being guided by bioactive screening,the anticomplementary constituents of P.urinaria were iso-lated and purified by solution partition and chromato-graphic techniques,and their structures were identified by 13C-NMR spectrum and the comparison of reported data. The anticomplementary activity and possible mechanism were assayed.Results The EtOAc fraction of the methanol extract of P.urinaria was shown to be the active fraction,and two compounds were purified from the fraction and were identified as corilagin and ellagic acid.The EtOAc and the two compounds signifi-cantly inhibited the hemolysis of the complement classi-cal pathway,with IC50values of 53.77 mg·L-1, 176.54 mg·L-1and 102.23 mg·L-1,respectively. While they just showed slight effect on inhibiting the hemolysis of the complement alternative pathway. All of them affected the formation of C3 convertase of the classical pathway. Conclusions The polyphenols are main anticomplentary constituents of P. urinaria,and its mechanism is related to inhibiting formation of C3 convertase of the classical pathway.
9.Effect of Necrostatin-1 on the inflammation in unilateral ureter obstruction mice
Xia XIAO ; Tao ZHANG ; da Xi YANG ; Qing TENG ; Jia HOU ; zhuo Yun REN
Chinese Journal of Clinical and Experimental Pathology 2017;33(8):863-867
Purpose To observe the effect of Necrostatin-1 (Nec-1),a necroptosis inhibitor,on the inflammation in unilateral ureter obstruction mice.Methods Male C57BL/6J mice were randomly divided into sham operation group,unilateral ureter obstruction operation group and UUO + Nec-1 treatment group,and the mice were sacrificed at 7th day after operated.Scr and BUN were measured.The pathological changes in the kidney were observed by HE staining.Immunohistochemistry and Western blot were used to detect the protein expression of necroptosis-related indicators RIP1,RIP3,MLKL and inflammatory cytokines TNF-α,IL-1β and MCP-1.Results Compared with sham operation group,the expression of RIP1,RIP3 and MLKL protein increased in the renal tissue of UUO mice,accompanied with increased expression of TNF-α,IL-1β and MCP-1.Nec-1 treatment significantly decreased above-mentioned protein expression in UUO mice,and also reduced renal interstitial inflammation and renal tubal injury according to HE staining.Scr and BUN levels suggested improved renal function.Conclusion Nec-1 could relieve the inflammatory reaction in renal tissue of the UUO mice by inhibiting necroptosis,which may be a new target for the treatment of secondary inflammation.
10.Effect of TGF-β1 gene-modified dendritic cells on expressions of CD28/CTLA-4:B7 in peripheral blood mononuclear cells in rats with experimental autoimmune myasthenia gravis
Yun-Fu WANG ; Sheng-Gang SUN ; Xue-Bing CAO ; Luo-Qing LI ; Xian QIAO ; Guo-Hou HE
Chinese Journal of Neuromedicine 2008;7(5):474-478
Objective To explore the effect of dendritic cells (DC) modified with transforming growth factor β1 (TGF-β1) gene on the expressions of CD28/CTLA-4:B7 costimulatory molecules in peripheral blood mononuclear cells (PBMC) in the Lewis rats with experimental autoimmune myasthenia gravis (EAMG). Methods Thirty inbreeding line, healthy, female Lewis rats were divided randomly into 6 groups: normal group, EAMG group, DC treatment group, pcDNA3-TGF-β1-DCtreatment group, pcDNA3-DC control group and normal saline group. The rats were immunized with the AChR protein extracted from electric organ of Narcine timilei and CFA in the groups except normal group. 2×106 pcDNA3-TGF-β1-DCs/rat were injected subcutaneously into the backs of the rats which had been immunized 5 d earlier with AChR+CFA. The rats in DC treatment group, pcDNA3-DC control group and normal saline group were injected in parallel with untreated DC, pcDNA3-DC and normal saline, respectively. Seven weeks after the first immunization, the expressions of CD28 mRNA and CTLA-4 mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR), and the levels of B7-1 and B7-2 on the surface of PBMC were examined using flow cytometry. Results (1)The low expression of CD28 mRNA and rare expression of CTLA-4 mRNA were found in the normal rats, and both expressions increased markedly in EAMG rats (P<0.001). Compared to those in EAMG group, the expression of CD28 mRNA decreased and CTLA-4 mRNA was upregulated after the treatment with pcDNA3-TGF-β1-DC (P<0.05). There was no significant difference in the expressions of CD28 mRNA and CTLA-4 mRNA among the EAMG group, DC treatment group, pcDNA3-DC control group and normal saline group (P>0.05). (2) The expressions of CD28, CTLA-4, B7-1 and B7-2 on the surface of PBMC were rare in normal rats, which increased significantly in EAMG rats (P<0.001). The levels of CD28, B7-1 and B7-2 in pcDNA3-TGF-β1-DC group were lower than those in EAMG group (P<0.01), but the level of CTLA-4 was higher than that in EAMG group (P<0.05). They showed no statistically difference among the EAMG group, DC treatment group, pcDNA3-DC control group and normal saline group (P>0.05). Conclusions The expressions of CD28/CTLA-4:B7 costimulatory molecules are abnormal in the rats with EAMG. The regulation of CD28/CTLA-4:B7 costimulatory pathways may play a critical role in the mechanism of the treatment with DC transfected with pcDNA3-TGF-β1 in the incipient EAMG rats.