Objective: The purpose of this study was to quantitatively assess the systematic and random errors in radiation therapy for pelvic tumor patients of different somatotypes and seek an individualized mathematic basis for defining the planning target volume(PTV) and planning organ at risk volume(PRV) in 3 dimensional space.Methods: Thirty patients with pelvic tumor were immobilized by thermoplastic body mask in a spine position and divided into four somatotypes according to their body mass indexes(BMI).CT simulations were performed and digitally reconstructed radiographs(DRR) were generated as the reference image.To define the appropriate PTV-and PRV-margins for intensity modulation radiated therapy(IMRT),inter-fractional set-up errors and intra-fractional organ motions were quantitatively evaluated in the right-left(R-L),anterior-posterior(A-P) and cranial-caudal(C-C) directions.And the frequency of shift in the three directions were observed.Results: For the pelvic tumor patients with different BMIs,the inter-fractional set-up errors of the emaciated,moderate,overweight and obese somatotypes were 1.8,1.8,2.2 and 2.7 mm in the R-L direction,2.2,1.8,3.6 and 2.8 mm in the A-P direction,and 2.4,2.1,2.7 and 2.6 mm in the C-C direction.The intra-fractional organ motions of the four somatotypes were 1.9,1.9,2.3 and 2.5 mm in the R-L,2.1,2.2,2.9 and 3.0 mm in the A-P,and 1.8,1.9,2.2 and 2.5 mm in the C-C direction.Conclusion: In the pelvic irradiation,the definition of PTV and PRV should be individualized.

Objective: To observe differentially expressed genes in rat hippocampus irradiated by 6 MV X-rays during radiotherapy.Methods:After whole brain irradiation of 50 Gy in 25 fractions with 2 Gy per fraction,the capability of learning and memory was investigated in a shuttle box model,then rats were killed and the hippocampus were taken,mRNA from sham irradiation group and irradiation group were reversely transcribed to cDNA with incorporation of fluorescence dUTP(Cy5 and Cy3 dUTP) to prepare for hybridization probes.The mixed probes were hybridized to the cDNA microarray.Axon Genechix 4000 BandGenePix Pro3.0 software was used to scan and analyze the fluorescent signals. Results:①The active avoidance response of irradiated rats were lowered significantly.②Compared with the sham group,significant changes took place in 43 genes,among which 28 genes were upregulated and 15 down regulated,other genes did not change significantly.③Among the 43 malexpressed genes,16 were reported previously,others were newly found genes. Conclusion: The influence of ionizing radiation on learning and memory was a complex course,including many transduction factors and might be related to mitochondrial dysfunction.

Objective To detect the spatial point pattern distribution rules of neural tube defects.Methods The kernel density estimation and Ripley's K-function were used to analyze the spatial point pattern of the neural tube birth defects in Heshun county in 1998-2001.Results The kernel density estimation result showed that there was two clusters' distribution in central area and southeastern area respectively.In addition,the result by the Ripley's K-function presented that the location of neural tube birth defects had a significant cluster tendency in the spatial distance from 3.17 to 10.41 kilometers in the investigated area.Conclusion These results can provide an important clue for identifying the relations between environment risk factors and birth defects in this area in the future.

Background and purpose:Accurate target delineation in IMRT setting has been a challenge for post-operative gliomas.The fusion technology with MR+CT image registration could improve the accuracy of target delineation,but there are no reports as to whether this technique could increase the stability of target delineation.This study was to investigate the accuracy of different fusion technologies with MRI+CT image registration so it could improve stability of target delineation of clinical target volume in patients with post-operative gliomas.Methods:The post-operative and pre-operative MRI+CT were registrated in nine patients with post-operative gliomas.Clinical target volume in the two registration images and localized CT images were delineated at 5 different times.The image registration accuracy and stability of target delineation were also quantitatively assessed.Results:The registration accuracy in 3D space was always less than 1.5 mm.The concordance index in CT+MRI(pre-matched),CT+MRI(post-matched)and CT(conv)were(68?9)%,(61?7)% and(41?12)% respectively.The same volumes delineated with three sets of images were(82?7)% for CT+MRI(pre-matched),(78?5)% for CT+MRI(post-matched)and(65?8)% CT(conv),respectively.Conclusions:The volume delineated according to pre-operative MRI registered with CT image have the largest volume and the best stability(P

ObjectiveTo detect the efficacy of compound matrine combined with intensity modulated radiotherapy (IMRT) for patients with locally advanced nasopharyngeal carcinoma (NPC). MethodsA total of 96 patients with locally advanced NPC were randomized into compound matrine combined with IMRT group (the therapeutic group) (n =48) and IMRT group (control group) (n =48). The nasopharyngeal DT and lymph nodes Dr were 66-78 Gy/(33-39 f)in 6-8 weeks,60-70 Gy/(30-35 f)in 6-8 weeks, respectively.The prophylactic dose of neck was 50-54 Gy.ResultsThe NPC efficacy of the therapeutic group was 93.8 ％(45/48)and control group was 79.2 ％(38/48).There was significant difference between the two groups in curative effect (P ＜0.05). The lymph nodes efficacy of the therapeutic group was 87.5 ％ (44/48) and control group was 75.0 ％ (30/48). There was significant difference between the two groups in curative effect (P ＜0.05). The side effects of mucosa were fewer in therapeutic group while the infection rate of pharynx oralis was higher in control group (P ＜0.01). ConclusionCompound matrine combined injection can improve shortterm curative effect of IMRT of locally advanced NPC and significantly decreased side effect of radiotherapy.

Objective To evaluate the survival and adverse effects of adjuvant concurrent temozolomid (TMZ) combined with radiochemotherapy in postoperative patients with high grade intracranial glioma.Methods 84 postoperative patients with high grade intracranial glioma were randomly divided into the observation group (42 cases including 25 grade Ⅲ cases and 17 grade Ⅳ cases) and the control group (42 cases including 23 grade Ⅲ cases and 19 grade Ⅳ cases).All patients were treated with concurrent radiochemotherapy after surgical operations,the total radiation dose was 60-66 Gy.The patients in observation group were given daily oral TMZ 75 mg/m2 during radiotherapy.4 weeks after radiotherapy,all of the patients received 6 cycles of TMZ,each cycle lasted 5 days with 28 days interval between each cycles.150 mg/m2 of TMZ was given for the first cycle for 5 days,followed by 200 mg/m2 of drug for the rest of the cycles if no significant drug related toxicities were observed.Results The overall response rates (CR+ PR) were 71.7 ％ (33/46) in the observation group,and 32.6 ％ (15/46) in the control group,and with significant difference between the two groups (P ＜ 0.001).The 1,2 and 3 year survival rates of patients in the observation group were 71.7 ％,47.8 ％,36.9 ％,and 56.5 ％,26.1％,15.2 ％ in the control group.The significant differences were found in 2-year and 3-year survival rates between the two groups (P =0.031,0.018).The median recurrent period in the observation group were 22 and 12 months in the control group,and with singnificant difference (P =0.015).The main side effects were limited to grade Ⅰ or Ⅱ.Conclusions Concurrent TMZ combined with radiotherapy in the treatment of high grade gliomas has better clinical efficacy,and can improve the 2-year and 3-year survival rates.Patients tolerate the strategy well and no severe toxicities are observed.

Objective: To study the accuracy of MRI-CT image registration in order to find a more effective method of image fusion and a standard for the evaluation of post-operative intra-cranial tumor radiotherapy.Methods: Twenty-four patients with intra-cranial tumor underwent MR T1-weighed sequence and post-operative location CT scan under the same location condition.The trans-axial MR T1-weighed sequence and CT image were registered and the correlation between registration scores and errors was analyzed by the method of Tris-Axes Landmark.The linear registration errors were observed in the three-dimensional space of every patient.Results: An improved linear correlation was found between registration scores and errors(r=-0.985,y=-0.551 3x+5.351 4).The registration met the clinical standard when the scores exceeded 6.61.Conclusion: Tris-Axes Landmark is a preferable registration method to be used in clinical radiotherapy for rapid and precise evaluation of MRI-CT image registration accuracy.

Objective To observe the effect of EGFR mutation on radiation induced DNA repair in pulmonary adenocarcinoma ceils.Methods A549 cells with wild-type EGFR and H1975 cells with mutated-type of EGFR were irradiated by 4 Gy of 6 MV X-rays.After irradiation,the formation of nuclear γ-H2AX foci was assayed with immunostaining method,the level of DNA-PKcs-EGFR interaction was detected with coimmunoprecipitation,and nuclear RAD51 expression and EGFR nuclear translocation were detected using Western blot.Results DNA repair in the H1975 cells was significantly lower than that in A549 cells.In the irradiated H1975 cells,there was no EGFR translocation with further nuclear DNA-PKcs binding,and the expression of nucleus RAD51 was not altered.But in the irradiated A549 cells,EGFRDNA-PKcs interaction and nucleus RAD51 were increased.Conclusions Lung adenocarcinoma cell line with mutations in the tyrosine kinase domain (TKD) of EGFR exhibits a high radiosensitivity due to the reduction of the non-homologous end-joining (NHEJ) and homologous recombination (HR) DNA DSB repair kinetics.

Objective To study the protective effects of vitamin E combined with Rhodiola rosea on the injury in mice skeletal muscle through hypoxia with exercise training and research the mechanism of action.Methods Forty ICR mice were randomly divided into control group and observation group,20 mice in each group.The control group was given Vitamin E (40 mg·kg-1·d-1),and the observation group was given Vitamin E (40 mg·kg-1·d-1)combined with Rhodiola rosea (20 g·kg-1·d-1);the rats in the two groups were treated with hypoxia (11.3%) for 4 weeks (5 ℃,15 m/min,60 min/d) after 15-day drug using.After the last training,all the mice were euthanized and then detected the gene of Bax and Bcl-2 mRNA through the RT-PCR in the skeletal muscle and the activity of GSH-PX,SOD,ROS,the concentration of MDA in the skeletal muscle.During the period (pretrain and 1,2,4 weeks) of hypoxia combined with exercise training,the CK,LDH in the serum were detected.Results The expression of CK and LDH in the observation group were lower than those of the control group (P<0.05).The activity of GSH-PX and SOD in the skeletal muscle of the observation group was significantly higher than that of the control group (P<0.05),while the ROS and MDA were lower than those of the control group(P<0.05);the expression of Bax mRNA and Bax/Bcl-2 of the observation group was significantly lower than that of the control group(P<0.05).While the expression of Bcl-2 mRNA was significantly higher than that of the control group(P<0.05).Conclusion Rhodiola rosea combined with Vitamin E can inhibit the expression of apoptotic genes by correcting the oxidation and hypoxia imbalance under hypoxia.

Objective: To observe the characteristics of dynamic changes of lysophosphatidic acid (LPA) levels in cerebrospinal fluid (CSF) in patients with subarachnoid hemorrhage (SAH) and its relationship with cerebral vasospasm (CVS) and to explore the pathogenesis of CVS. Methods: Sixty-seven patients with SAH diagnozed by clinical and accessory examinations were selected. The LPA levels in CSF were measured at 24 hours, day 7,14, and 28 respectively after the onset of symptoms,and they were compared with a control group. The correlation between LPA levels and CVS on the time course was also observed at the same time. Results: Of the 67 patients with SAH, a total of 29 patients (43.3%) occurred CVS, the average time of occurrence was 6. 6 days. There was no significant difference between the LPA levels in CSF in patients with SAH and the control group at 24 hours after the onset of symptoms; they were significantly higher than the control group at day 7 (P ＜0. 001); they were significantly higher than the control group at day 14 (P ＜ 0. 001), but they were significantly lower than those at day 7 (P ＜ 0. 01); they decreased to baseline at day 28, and there was significant difference compared with the control group. There was no significant difference between the LPA levels in the CVS group and those in the non-CVS group at 24 hours, they were significantly higher than those in the non-CVS group at day 7 (P ＜0. 001), they were still significantly higher than those in the non-CVS group at day 14 (P ＜0. 01); and there was no significant difference between the 2 groups at day 28. Conclusions: The LPA levels in CSF in patients with SAH increased significantly from day 7 to day 14 after the onset of symptoms, and they had obvious association with CVS on the time course. The detection of the LPA levels in CSF may have important significance in predicting the occurrence of CVS.