Objective To investigate a new automatic inverse optimal solution based on VMAT optimization model and verify its result.Methods A variant of the new automatic inverse optimal solution was proposed in this study,which provided a solution to calculate treatment plan with the minimized number of beams and the minimized levels of their intensities on the basis of VMAT optimization model by customized software tools.The verifications were evaluated on the simulated head-neck phantom by dosimetric parameters.Results Compared with conventional IMRT/VMAT treatment plans,the adaptive optimization program(AOP)plan showed that plan20/40(20 fields with totally 40 sub-fields,m=2)made the best achievement and it was clinicable.Conclusions The proposed new optimization technique provides an effective way to reach an inverse treatment plan with the best compromise and less sub-fields compared with IMRT/VMAT plans.

Objective To dosimetrically compare three delivery techniques of VMAT,IMRT and 3D-CRT in the treatment of accelerated partial breast irradiation (APBI).Methods Twenty patients with T1/2N0M0breast cancer were treated with VMAT.These cases were subsequently re-planned using static gantry IMRT and 3D-CRT technology to evaluate dosimetric differences.Dosimetric parameters including dose conformity index (CI),dose volume histogram (DVH) analysis of normal tissue coverage,dose parameters of PTV and normal tissues were evaluated,the delivery parameters including MU and delivery time were also analyzed.Results The IMRT and VMAT plans provided lower maximum dose,better mean dose and more conformal target dose distributions than the 3D-CRT plans (F =14.86,8.57,18.23,P ＜0.05).The volume of ipsilateral breast receiving 5 Gy for VMAT technique was significantly less than that of3D-CRTor IMRT(F=5.83,P＜0.05).The ipsilateral lung volume receiving 20 Gy (V20),5 Gy(V5) and the 5％ volume dose (D5) of IMRT were superior to those of 3D-CRT and VMAT(F =16.39,3.62,4.81,P ＜ 0.05).The low volume dose distributions of D5 in contralateral lung for IMRT was better than that of VMAT and 3D-CRT(F =3.99,3.43,P ＜ 0.05).The total mean MUs for VMAT,3D-CRT and IMRT were 621.0 ± 111.9,707.3 ± 130.9 and 1161.4 ± 315.6,respectively (F =31.30,P ＜ 0.05).The average machine delivery time was(1.5 ± 0.2)min for the VMAT plans,(7.0 ± 1.6)min for the 3D-CRT plans and (11.5 ± 1.9)min for the IMRT plans.Conclusions VMAT and IMRT techniques offer improved dose conformity as compared with 3D-CRT techniques without increasing dose to the ipsilateral lung.In terms of MU and delivery time,VMAT is more efficient for APBI than conventional 3D-CRT and static beam IMRT.

BACKGROUND:The glial scar is a major obstacle to the regeneration of the central nervous system, which plays a physical and chemical barrier role to central nervous system regeneration. How to effectively inhibit glial scar formation and promote axonal regeneration has great significance.
OBJECTIVE:To explore the effect of the immune response in the formation of the glial scar after spinal cord injury.
METHODS:A computer-based online search was performed in the PubMed database and the CNKI database for the articles on the mechanisms of spinal cord injury, immune cel s and spinal cord injury as wel as the glial scar formation after spinal cord injury from January 1990 to January 2013. The key words were “spinal cord injury, immunity, glia scar”in Chinese and English. The languages of the articles were limited in Chinese and English. Final y, 72 articles were included for the further analysis according the inclusion criteria.
RESULTS AND CONCLUSION: After spinal cord injury, the effect of autoimmune response in which stil been much debated. Studies showed that spinal cord injury can cause suppression of cel ular immunity and non-specific immune function, causing immune function decreasing. Monitoring immune indicators and improving immune function have great significance in promoting the ful rehabilitation of patients with spinal cord injury. Glial scar is the most important factor to prevent the repairing after spinal cord injury. Immune and inflammatory response is the main reason to secondary spinal cord injury. Degree of repair after spinal cord injury mainly depends on the protection of the residual neurons in order to keep them off secondary damage. However, autoimmune T cel s can protect the residual neurons, the specific effect of T lymphocytes in glial scar formation after spinal cord injury is stil unclear, and further exploration is needed.

BACKGROUND: There are currently many cryopreservation methods for the aminotic membrane, which have varying effects on the ultrastructure and biological activity of amniotic membrane, but on no one is effective.
OBJECTIVE: To compare the effects of different cryopreservation methods on the ultrastructure and viability of aminotic membrane and to seek the ideal cryopreservation method.
METHODS: Aminotic membrane separated from the fresh placenta was preserved respectively with deep-frozen cryopreservation and vitrification, and everyway was run for 3 and 6 months. Fresh aminotic membrane was used as control. The ultrastructure of aminotic membrane was observed by transmission electron microscopy, and the viability of aminotic membrane was assessed by microcomputer analysis system for biological oxygen consumption, and immunohistochemical staining combined with image analysis system was used for lactate dehydrogenase activity.
RESULTS AND CONCLUSION:After 3 and 6 months of crypreservation, the damage to the ultrastructure of aminotic membrane by vitreous cryopreservation was slighter than that of amniotic membrane cryopreserved at-80℃. Compared with the fresh aminotic membrane, the gray value of lactate dehydrogenase and partial pressure of oxygen were significantly decreased in the cryopreserved aminotic membrane by deep-frozen cryopreservation at 3 and 6 months (P < 0.05) and by vitreous cryopreservation at 6 months (P < 0.05), but there was no statisticaly significant difference in the change rate of oxygen partial pressure and the gray value of lactate dehydrogenase between the fresh aminotic membrane and the cryopreserved aminotic membrane by vitreous cryopreservation at 3 months. The present study led to the conclusion that vitreous cryopreservation protocol alows to not only maintain the integrity of AM, but also to preserve the viability of the cels. So the vitreous cryopreservation is superior to the deep-frozen cryopreservation for cryopreservation of aminotic membrane.

Objective To explorer the application in detection the position accuracy of the multileaf collimator of Varian accelerator with dynamic therapy log files. Methods A pre-designed MLC format files named PMLC for two Varian accelerators, the dynamic treatment log files were recorded 10 times on a different date, and be converted into the MLC format files named DMLC, compared with the original plan PMLC, so we can analysis two files for each leaf position deviation. In addition, we analysis the repeatability of MLC leaves position accuracy between 10 dynalog files of two accelerators. Results No statistically significant difference between the average position of the 10 times leaf position of the two accelerators,their were 0. 29 -0. 29 and 0. 29 -0. 30(z = -0. 77, P=0. 442). About 40% ,30% ,20% and 10% of the leaf position deviation was at ≤0. 2 mm, 0. 3 mm,0. 5 mm and 0. 4 mm,respectively. the maximum value was 0. 5 mm. More than 86% of the leaf position are completely coincident between 10 dynamic treatment files of two accelerators,The rate of position deviation no more 0. 05 mm was 96. 6% and 97.3%, respectively.And the maximum value was 0. 09 mm. Conclusions Dynamic treatment log file is a splendid tool in testing the actual position of multi-leaf collimator. The multi-leaf collimator of two accelerators be detected are precise and stabilized.

Objective To explore the factors related to the delayed graft function (DGF). Methods Clinical data of 150 recipients were collected and performed by Cox proportional hazards regression analysis . In addition, the glutathione S-transferase (GST) gene polymorphism of 172 donors and 157 healthy persons was analyzed by multiple PCR and SSP-PCR. Results DGF was observed in 24 patients among 150 recipients. Pretranplantation dialysis mode, PR A levels and recipient gender were uncorrelated with the incidence of DGF(P>0. 05). Urinary volume of the second 24 hours after transplantation was an independent predictor of DGF(RR=1. 002, P = 0. 001). The frequency of donor's null GSTM1 in DGF group was significantly higher than that in non-DGF group(P<0. 05). Conclusions Urinary volume of the second 24 hours after transplantation could be a predictor for DGF. The null GSTM1 in donor might be one of the factors related to the EGF.

Objective To evaluate the feasibility and accuracy of performing dose calculation on megavoltage cone-beam CT(MVCBCT) in the head and neck. Methods MiniCTQC phantom was imaged using MVCBCT scanner, and the MVCBCT value density calibration curve was established. Conventional CT and MVCBCT image of phantom and nasopharyngeal carcinoma(NPC) patient were acquired respectively. Two kinds of single field plan were designed for conventional CT image of phantom,and IMRT plan was used for conventional CT image of a NPC patient. The conventional CT plans were copied to MVCBCT image. The dose distribution was calculated for targets and normal tissues using the MVCBCT value density calibration curve,and compared with that of conventional CT. Results For all the cases,the differences between the calculated dose distributions using MVCBCT and CT were less than 3% and 3 mm in single field plan. In IMRT plan, DVHs of conventional CT and MVCBCT were in excellent agreement. The biggest difference between conventional CT and MVCBCT was 95 cGy with the error of 1.4%. On the isocenter plane,the passing rate was 95.5% ,99.4% ,93.8% ,98.7%, 100% ,94.5% ,97.3% ,95.6% ,99.3% and 99.4% for the beam angle of 0°,45°,90°,120°,160°,200°,240°,280° and 320°. Conclusions Performing dose calculation using MVCBCT in head-and-neck region was feasible, and the dose distributions on the conventional CT and MVCBCT were in excellent agreement.

Objective To explore the diagnosis and surgical treatment of ileosigmoid fistulas (ISF) complicated by Crohn's disease (CD).Methods 13 CD patients with ISF were collected.Patients' clinical data,diagnostic methods,surgical procedures and outcomes were reviewed.Results Suspected or definite diagnosis was suggested by preoperative imaging in 12 patients.All 13 patients received surgery.Ileal lesions were all removed,while sigmiod fistula were repaired in 11 patients and partially resected in 2 patients.11 patients had a temporary ileostomy.All the patients recovered well,with 3 cases suffering from postoperative complications.Conclusions The diagnosis of ISF can be established preoperatively,and treatment should be individualized to patient' condition.

BACKGROUND: Acetabular malignant tumor reconstruction is to obtain pelvic stability and lower limb walking function to excise the tumor at safe margin.Excision range has been evaluated by MRI,CT,X-ray,which are subjective and lack preoperative design.Computer-aided three-dimensional reconstruction can evaluate tumor erosion range from all planes to accurately excise the tumor.OBJECTIVE: To evaluate the value of computer aided design in the treatment of acetabular malignant tumor.METHODS: One case with acetabular hemangiosarcoma was checked with lamellar CT scanning,which acquired some two-dimensional data in disease area.The three-dimensional reconstruction of anatomical model,design of cutting bone extent,design of individual prosthesis and sham operation were made by computer.Based on computer aided design proposal,acetabular tumor was resected,pelvic ring and right hip articulation were reconstructed with allogeneic semi-pelvis and individual total hip replacement.RESULTS AND CONCLUSION: The patient began to non-weight bearing walk with double crutches 2 months after operation.At6 months,the patient walked normally.The right hip joint motion was good with no pain.Postoperative X-ray film displayed individual prosthesis matched to pelvis.The patient fell a little numbness of skin in the lateral of right hip.No phlebothrombosis,prosthesis loosening or dislocation was found.Computer aided design has a good perspective of application in the treatment of acetabular malignant tumor.Individualized treatment can improve operation accuracy,reliability,convenience and curative effect.

Objective To investigate the association of genetic polymorphisms in glutathione S-transferases T1 (GSTrl), M1 (GSTM1) and P1 (GSTP1) with aristolochic acid nephropathy (AAN) of Chinese people in Wenzhou of China. Methods Fifty-nine patientswith AAN (AAN group) including 29 male and 30 female as well as 157 healthy ethnically matched controls (control group) including 93 male and 64 female were enrolled in this study. The genotypes of GSTT1, GSTMI and GSTP1 were determined by multiple PCR and confronting two-pair primers PCR (CTPP-PCR). Results The genotype frequencies of GSTP1 were in Hardy-Weinberg equilibrium. Compared with the healthy controls, the frequency of GSTT1 null genotype was significantly higher in the patients with AAN (66.1% vs 48.4%,P＜0.05). Risk of A.AN for individuals with GSTT1 null genotype was 1.747 fold of those without GSTIl null genotype (95% CI=0.818-3.731). The frequency of GSTM1 null genotype, GSTP1 variant genotypes and GSTP1 G allele in the patients and in the controls were 40.7%, 28.8%, 16.1% and 47.8%, 31.8%, 17.5%, respectively, which were not significantly different. No significant differences were found in prevalence of GSTM1 and GSTP1 gene distribution between patients and controls. Conclusion GSTrl gene polymorphism appears to be associated with susceptibility to AAN in Southern China.