1.A comparison of the dosimetric effects of systematic MLC leaf position errors on flattening filter and flattening filter-free IMRT for nasopharyngeal carcinoma
Lele LIU ; Yangguang MA ; Guowen LI ; Yuexin GUO
Chinese Journal of Radiological Medicine and Protection 2015;35(11):835-838
Objective To compare the dosimetric effects of systematic MLC leaf position errors on flattening filter (FF) and flattening filter-free (FFF) IMRT for nasopharyngeal carcinoma (NPC).Methods In totaly of ten patients with NPC were enrolled in the current study.FF IMRT and FFF IMRT plans were designed for each patient, and in-house software was developed to modify the corresponding MLC files.Briefly, three kinds of systematic MLC error presented with 0.5 and 1 mm magnitudes error were simulated.The modified MLC files were re-imported into IMRT plans for dose recalculation, and differences in the dosimetry trends between FF-IMRT and FFF-IMRT plans were analyzed using a dosevolume histogram.Results Upon closed MLC, the average changes in D95% of PTV and D of parotid glands in FFF-IMRT plans were more sensitive than in FF-IMRT plans (t =3.298-4.793, P < 0.05).Otherwise, when MLC are shifted in the same direction, changes in D95%of PTV, D of PGTV, PTV as well as D of left parotid gland in FFF-IMRT plans were also more sensitive (t =2.372-6.844, P < 0.05), whereas average changes in D of right parotid gland presented with less sensitivity (t =-4.049,-3.378, P < 0.05).Conclusions For out-of-field or large organs, FFF-IMRT plans are more sensitive to leaf position error than FF-IMRT plans.
2.THE RESEARCH ON APPLICATION IN THE EDUCATION WITH GLYCEMIC INDEX IN DIABETIC PATIENTS
Yinfa ZHANG ; Yuexin YANG ; Zhongliang MA ; Junhua HAN ; Zhu WANG
Acta Nutrimenta Sinica 1956;0(03):-
Objective: To examine the effects of the education with glycemic index(GI)on dietary knowledge,attitude and practice of diabetic patients,and on their blood glucose and lipid.Methods: Seventy-two subjects with type 2 diabetes were randomly assingned into two groups. The test group (group GI) mainly learned the knowledge about GI of food. The controlled group (group FEL) mainly learned the knowledge about food exchange list(FEL). Outcomes were assessed by the change of dietary knowledge, attitude and practice, fasting blood glucose (FBG), 2 h postprandial blood glucose ( 2 hPBG), glycosylated hemoglobin (HbA 1c), and blood lipids which include total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG) and lipid comprehensive index (LCI). The period lasted five months. Results: The percent of correct answer for GI questions was increased significantly from 0 % before education to 92.2% after education (P
3.A comparative analysis of Matrixx and EPID for dosimetric verification of intensity-modulated radiotherapy
Yuexin GUO ; Yuntong PEI ; Yangguang MA ; Fei JIA ; Haiyang WANG
Chinese Journal of Radiation Oncology 2017;26(6):657-660
Objective To compare the dosimetric verification results of Varian Portal Dosimetry and Matrixx,and to assess the reliability of the clinical application of electronic portal imaging device (EPID) verification.Methods Varian TrueBeam linear accelerator,which was equipped with a 120-leaf multileaf collimator and an amorphous silicon EPID,as well as portal dose prediction software.IBA I′mRT Matrixx ion chamber array was used.EPID algorithm configuration,dose calibration,and testing before use were performed.The sliding-window protocol was used.There were 77 patients with tumors involving the head and neck (mainly nasopharyngeal carcinoma),mediastinum,abdomen,and pelvic cavity were selected.The verification plan of the portal dose was created with a source-detector distance of 100 cm,and the gantry angle was kept the same as the treatment plan.The verification plan was carried out in the TrueBeam machine,and the data were collected at the same time by EPID.Comparison between the measured and calculated dose images was performed,and the evaluation standard was gamma index (3%/3 mm).The paired t-test was used for difference analysis.Results For the 77 patients,the Gamma passing rates of both methods were above 97%.Except for head and neck carcinoma were a significant difference between the results of dosimetric results using EPID and Matrixx in intensity-modulated radiotherapy (P=0.018) other remaining all P> 0.05.Conclusions The dosimetric verification results of EPID are consistent with those of Matrixx.EPID can be used for dosimetric verification,and Matrixx ion chamber array can be used only in case of a low Gamma passing rate.
4.The expressions and significance of caspase-3 and E-cad in the tissues of Uygur patients with acquired immunodeficiency syndrome-related and classical Kaposi′s sarcoma in Xinjiang
Rongjiong ZHENG ; Xuefeng WAN ; Kejun PAN ; Linlin HUANG ; Rui MA ; Fangrong JIE ; Yuexin ZHANG ; Xiaobo LU
Chinese Journal of Infectious Diseases 2017;35(2):70-73
Objective To further clarify the pathogenesis of different types of Kaposi′s sarcoma (KS) by measuring the protein expressions of caspase-3 and E-cad in tumor tissues of Xinjiang Uygur patients with acqured immunodeficiency syndrome (AIDS)-Kaposi′s sarcoma (KS) and classical KS.Methods From July 2011 to October 2014, 38 patients with KS at the First Affiliated Hospital of Xinjiang Medical University and Urumqi Infectious Disease Hospital were enrolled, among whom 28 were male and 10 were female, and all of them were uygur.Immunohistochemical and Western blot methods were used to detect the expressions of caspase-3 and E-cad proteins in 22 cases of AIDS-KS patients and 16 cases of classic KS.The quantitative data of normal distribution were analyzed by t test, while count data were compared with χ2 test with R × C table.Results KS lesions in patients with classic KS were confined to the skin, without mucosal, lymph node or visceral involvement.Lesions in AIDS-KS patients were not only confined to the skin and superficial lymph nodes, but also oral mucosa involved in 12 cases and internal organs involved in 7 cases.Liver and lung involvement was more common.The CD4+T lymphocyte count in patients with AIDS-KS was (200.8±166)/μL.All 15 AIDS cases with CD4+ T cell count less than 200/μL developed opportunistic infections.CD4+ T lymphocyte count of patients with classic KS was (562.52±222.66)/μL and the 16 patients with CD4+T lymphocyte count greater than 350/μL had no opportunistic infections.The results of immunohistochemistry showed that the positive expression rate of caspase-3 protein in KS tissues in patients with AIDS-KS was 68.2%, in patients with classic KS was 100.0%, with significant difference between two groups (χ2=7.37, P=0.01).The positive expression rate of E-cad protein in KS tissues in patients with AIDS-KS was 72.7%, in patients with classic KS was 100.0%, with significant difference between two groups (χ2=5.18, P=0.03).Western blotting showed that the gray value of caspase-3 in the KS tissue of patients with AIDS-KS was 0.55±0.36, and that in patients with classic KS was 0.86±0.56, with significant difference between two groups (t=-2.070, P<0.05).The gray value of E-cad in the KS tissue of patients with AIDS-KS was 0.54±0.41, and that in patients with classic KS was 0.85±0.45, with significant difference between two groups (t=-2.060,P<0.05).Conclusions There are differences in the protein expressions of caspase-3 and E-cad in tumor tissues of patients with AIDS-KS and classical KS in Xinjiang Uygur patients with Kaposi's sarcoma, which may correlate with a faster progression and a higher mortality rate for AIDS-KS.
5.Development of a new special ambulance for airfield
Junsheng YOU ; Yuexin MA ; Yong YOU ; Dongchen YIN ; Xuyao XU ; Wei SUN ; Xiaohong GUAN
Chinese Medical Equipment Journal 2003;0(11):-
Objective To develop a special ambulance for airfield rescue of pilots in danger or offering medical care for pilots in flight.Of course the ambulance can also be used to rescue the wounded daily or in the war.Methods The ambulance owned a cross-country motorcar chassis and bearing carriage.A luffing extension-jib was installed on top of the carriage with a telescopic nacelle.The medical carriage owned a generator,air-conditioner,launder & antisepsis facilities,telescopic medical table,Air Force medical facilities for first aid and so on.It could simultaneously treat 2 injured pilots in lying position.Oxygen outputs were equipped to sustain Persons in carriage.Result The maximal speed of the ambulance was 95 km/h.The time of simulated rescue was about 3 minutes in the maxium height.Conclusion Without new staff established,the ambulance can adapt to any road and is suitable to war field.It can arrive at the location of flight accident quickly and rescue the pilot rapidly.It meets the needs of medical support in flight,war-time medical care in airport and mobile accompanying support.
6.Evaluation the combined effect of three dose reconstruction systems on VMAT dosimetry verification of lung cancer
Yangguang MA ; Rizhen MAI ; Yuntong PEI ; Jinyan HU ; Fanyang KONG ; Xuemin WANG ; Yuexin GUO
Chinese Journal of Radiation Oncology 2021;30(1):76-80
Objective:To evaluate the combined effect of an trajectory log field based(LBF)and two commercial dose reconstruction systems on volume-modulated arc therapy(VMAT)dose verification of lung cancer.Methods:An in-house program was developed to introduce errors in trajectory log of TrueBeam to the origin plan and recalculate the dose of the error plan in treatment planning system(TPS). A total of 18 lung cancer cases treated by two-arc VMAT were selected to perform on LINAC and measured by ArcCheck simultaneously. Then, the reconstructed doses were obtained by 3DVH. The mode of reconstruction was calculated by LFB and Compass. Five of the 18 cases were performed on LINAC two times in four hours and measured by ArcCheck to evaluate the stability of the TrueBeam performance. The 18 plans were recalculated and performed on LINAC with a solid water phantom with 5 cm build-up, 4 cm back scattering thickness and a FC65-G detector in the center. The measured dose by detector was compared with the reconstructed dose by three systems.Results:TheTruebeam performance was stable. For all of the 18 cases, the point dose measured by FC65-G and reconstructed by three systems had a deviation of less than 2% to the TPS calculated. For all of the organs reconstructed by LBF and most organs reconstructed by 3DVH and Compass, the γ pass rate between them and TPS all exceeded 90% under all criteria, as well as the ArcCheck measured results. For all the organ dose difference between reconstructed and TPS, LBF system had the smallest difference, followed by the Compass system except the lung, and the 3DVH had the highest difference.Conclusions:LBF, 3DVH and Compass can reflect the VMAT dose verification results of lung cancer from different perspectives. The combined application of three systems can demonstrate the verification results in an intuitive manner, which is beneficial for subsequent analysis.
7.Protective effect of Xinyi capsule pretreatment on myocardial ischemia reperfusion injury in rabbits
Yuexin ZHU ; Kai MA ; Yong CAO ; Xiangyu LI ; Yixuan ZHOU ; Lei ZHOU ; Mei DONG ; Li LI
International Journal of Traditional Chinese Medicine 2015;(1):56-60
Objective To investigate the protective effect of Xinyi capsule pretreatment on myocardial ischemia reperfusion injury in rabbits and its possible mechanism. Methods Ninety-four rabbits were randomly divided into 6 groups: model group (n=16), tirofiban group (n=16), high-, medium- and low-dose Xinyi capsule groups (4.0, 2.0, 1.0 g/kg;n=16 in each group), and sham operation group (n=14). Five days after intragastric administration with drug, myocardial ischemia reperfusion was induced by ligation of the proximal left circumflex artery. The electrocardiogram (ECG) was continuously recorded. The serum levels of myeloperoxidase (MPO), lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) were measured. Myocardial histopathological damage was evaluated. Results The changes of J-point amplitude on ECG in high-, medium-and low-dose Xinyi capsule groups (0.064 ± 0.049 mV, 0.069 ± 0.061 mV, 0.079 ± 0.060 mV) were significantly lower than that in the model group (0.158 ± 0.105 mV, P<0.01 or P<0.05), the serum levels of LDH (399.7 ± 202.3 U/L, 369.6 ± 229.0 U/L, 435.5 ± 152.4 U/L), CK-MB (900.8 ± 231.2 U/L, 1 268.3 ± 899.8 U/L, 1 386.7 ± 621.6 U/L), MPO (69.81 ± 5.51 U/L, 85.44 ± 10.31 U/L, 81.33 ± 16.87 U/L) were significantly lower than those in the model group (LDH:817.1 ± 401.9 U/L, CK-MB:2 071.3 ± 693.5 U/L, MPO:149.9 ± 20.11 U/L;P<0.01 or P<0.05). Histopathological examination showed that myocardial damage in high-, medium- and low-dose Xinyi capsule groups reduced compared with the model group. Conclusions Xinyi capsule pretreatment can protect against myocardial ischemia reperfusion injury in rabbits, and its mechanism may be related to inflammation inhibition.
8.The biologic characteristics of human immunodeficieney virus-1 subtype B' R5 tropic strains in different disease stage
Yanfang GUO ; Liying MA ; Yuexin ZHANG ; Lin YUAN ; Jianping SUN ; Weisi XU ; Quanbi ZHAO ; Shuilin QU ; Yang HUANG ; Yiming SHAO
Chinese Journal of Infectious Diseases 2008;26(7):425-429
Objective To study biological characteristics of R5 tropic human immunodeficiency virus (HIV)-1 strains in different disease stage. Methods Primary clinical viruses were isolated from fresh peripheral blood mononuclear cells (PBMC) using co-culture methods; meanwhile, viral co receptor usage and infectivity were tested using flow cytometry on GHOST (3) cell lines,which expressed CD4 receptor and CC ehemokine receptor 5 (CCR5) or CXCR4 eoreceptor; to identified CCR5 tropic viruses(R5 tropic strains). Viral replication kinetics was detected in PBMCs. Plasma viral load was measured using an HIV-1 nucleotide fluorescence quantification assay kit. Results There were 22 individuals with HIV-1 subtype B' infection, in which 11 were CD4>0. 2 × 109/L and 11 were CD4≤0. 2 × 109/L. All isolated viruses used CCR5 coreceptor and therefore were HIV-1 R5 tropic strains. The infectivity of R5 tropic strains isolated from patients with CD4≤0.2 × 109/L was (7.392 7 ± 4. 584 2) % ; while the infectivity of R5 tropic strain from patients with CD4>0. 2 × 109/L was (2. 613 6 ± 1. 610 5)%. There were significant statistical difference(t= 3. 262, P<0.05). The possibility of viral replication became strong after the day 7 post-infection. There was a significant difference of viral replication between two groups in the day 7,10, 15 post-infection(t value was 3. 771, 2. 509 and 2. 260 respectively, P<0. 05). The possibility of viral replication was higher in CD4≤0.2 ×109/L group than that of CD4>0.2 × 109/L group. The logarithm of viral load was (5. 606 8 ± 0. 815 1 ) copies/mL in CD4≤0.2 × 109/L group and (4. 729 8 ± 0. 431 6) copies/mL in CD4> 0.2 × 109/L group. There was a significant difference between two groups(t = 3. 771 ; P<0.05). Conclusion Viral infection and replication are enhanced during progression of disease, even if viral coreceptor usage do not switch from CCR5 to CXCR4.
9.Effects of experimental varicocele on mitochondria calcium and cytochrome C of the epididymis in adolescent rats.
Xiaoru MA ; Shuqiu WANG ; Yuexin WANG ; Shuxiang WANG ; Weiqun WANG ; Jianhua ZHANG ; Yongyi LI
National Journal of Andrology 2004;10(6):420-422
OBJECTIVETo investigate the effects of experimental varicocele on mitochondria calcium and cytochrome C of the epididymal cells in adolescent rats.
METHODSForty male adult Wistar rats were divided into two groups randomly: varicocele group (VG) and sham operation group (SOG) by partial ligation or exposure of the left renal vein. Bilateral epididymides were removed after ten
RESULTSThe content of mitochondria weeks. Mitochondria calcium and cytochrome C levels of the epididymal cells were detected. calcium decreased (P < 0.001 ) while that of cytochrome C increased (P < 0.05) markedly in the experimental group compared with SOG.
CONCLUSIONCalcium dyshomeostasis and mitochondrial damage of the epididymal cells caused by varicocele may play an important role in leading to subfertility.
Animals ; Calcium ; metabolism ; Cytochromes c ; analysis ; Epididymis ; metabolism ; Infertility, Male ; etiology ; Male ; Mitochondria ; metabolism ; Rats ; Rats, Wistar ; Varicocele ; metabolism
10.Preliminary application of volumetric-modulated arc therapy dosimetry verification system based on three-dimensional dose reconstruction of patient anatomical structures
Yangguang MA ; Rizhen MAI ; Yuntong PEI ; Yuexin GUO
Chinese Journal of Radiation Oncology 2022;31(2):170-175
Objective:To perform testing and clinical application of a volumetric-modulated arc therapy (VMAT) dosimetry verification system based on three-dimensional dose reconstruction of patient anatomical structures.Methods:ArcCheck array calibration was performed. Then, 200 MU was delivered with a 10 cm×10 cm field when the source to center of ArcCheck was 100 cm to calibrate the absolute dose and the dose was simultaneously measured by a FC65-G detector in the center of the ArcCheck. The absolute dose calibration value or the CT value of ArcCheck was adjusted to minimize the differences between the planning and measurement values of FC65-G, reconstructed value by 3DVH and reconstructed percent depth dose by 3DVH. 10 lung and 10 cervical cancer VMAT cases were selected and measured by ArcCheck and FC65-G under the delivery of a TrueBeam LINAC. The three-dimensional doses of all cases were reconstructed by 3DVH and compared with the planning and measurement values.Results:Different array calibration files of ArcCheck exerted different effect upon the two-dimensional dose measured by ArcCheck and three-dimensional dose reconstructed by 3DVH. The optimal reconstructed dose was obtained when self-calibration file was adopted and 249.96 cGy was regarded as the absolute dose calibration value. The deviations of the mean dose (D mean) and D 95% of the target were within ±4.2% and parameters of some organs at risk significantly differed compared with the reconstructed and planning dose for all cases. A negative mean point dose difference was obtained and the reconstructed dose was closer to the measured value. The γ-passing rate of the target for some cases was low, the proportion of regions irradiated by 50% prescription dose was slightly higher and the proportion of other organs was relatively high. Conclusion:The 3DVH model can be accurately established and tested with the acceptance test method in the present study, which can provide detailed information for dose verification.