The effects of immediate administration of inderal following acute myocardial infarction on left ventricular remodeling were studied in acute myocardial infarction model of the rabbit. The results showed that there was no significant difference in the infarct size and expansion index between the infarct-inderal group and the infarct-placebo group. As compared with sham surgery-inderal group，infarct-inderal group had a higher ventricular weight，left ventricular volume index and left ventricular wall stress ［(2.65±0.17) g/kg vs (2.32±0.11) g/kg，P<0.05;(2.22±0.23) ml/kg vs (1.70±0.12) ml/kg，P<0.001;(0.84±0.07) vs (0.75±0.052)，P<0.05，respectively］，but there was no significant difference between the infarct-inderal group and infarct-placebo group. Heart rate in the infarct-inderal group was significantly decreased as compared with that of infarct-placebo group ［(153±6.36) min－1 vs (225±4.08) min－1，P<0.001］，but there was no significant difference in left ventricular end-diastolic pressure，+dp/dt max and cardiac index between the two groups. It was suggested that immediate administration of inderal postinfarction had no preventive effect on left ventricular remodeling.

Objective Rats bladder ncNOS IR following intravesical instillation of capsaicin after chronic spinal cord injury(SCI) was studied to investigate the mechanism of ncNOS IR in pathological bladder. Methods 44 adult Sprague Dawley rats were randomly divided into normal group,sham injury group and spinal cord injury group(4～5 weeks after T 8～9 spinalization).A dose of 1 mmol/L capsaicin was instilled in part of SCI rats.the distribution of ncNOS IR in bladder base,bladder body and bladder dome of all rats were examined. Results In rats,the ncNOS IR did not differ between the normal group (11.1?0.9) and the SCI group (12.8?1.3).Intravesical instillation of capsaicin significantly up regulated ncNOS IR in rat bladder of SCI group (26.1?2.7, P

AIM: To study the relationship between respiratory syncytial virus (RSV) infection and apoptosis, between RSV infection and expressions of FasL, Fas, Bcl-2 and Bax. METHODS: Apoptotic cells were examined by flow cytometry and transmission electron microscope. Immunohistochemical analysis was used to detect the expressions of apoptosis-associated gene FasL, Fas, Bcl-2 and Bax in A549 cells during RSV infection. RESULTS: Apoptotic index increased at 72 h and 120 h postinfection. Apoptotic cells were detected by transmission electron microscope. High-expressions of FasL, Fas and Bax genes and low-expression of Bcl-2 gene were detected by immunohistochemical staining. CONCLUSION: Apoptosis in A549 cells was induced by RSV infection. This apoptosis may be induced by up-regulating the expression of FasL, Fas, Bax genes and down-regulating the expression of Bcl-2 gene.

Objective To investigate feasible immunotherapy strategy using tumor specific cell against osteosarcoma,and to analyze the therapeutic effect of adoptive cellular infusion therapy on osteosarcoma.Methods Decitabine (DAC) was employed as a hypomethylating agent for the treatment in osteosarcoma cell lines HOS and U2OS.After treatment,the expression of cancer-testis antigen (CTA) was evaluated by PCR and Western Blot.In animal studies,human osteosarcoma cell line HOS,which was transfected by luciferase and HLA-A0201 in previous,was inoculated into immune deficient NOD-SCID mice to establish osteosarcoma xenografts.Ex-vivo expanded CTA specific homo CD8+T-ells were labeled with DiR and injected into the mice via the tail vein.In vivo imaging system was utilized to detect the distribution of administrated CD8+ T-cells.In addition,the progression of tumor xenografts was monitored.Moreover,mouse K7M2 osteosarcoma cell line was used to establish animal models in immune competent BALB/c mice.Immune competent models were utilized to evaluate the effectiveness of hypomethylating treatment in regarding to spontaneous immune attack against tumors.Flow cytometry was used to analyze the proportion of intratumoral lymphocytes and the status of these effector antitumor immune cells,and to reveal the effect of hypomethylating treatment in facilitating lymphocyte infiltration and activation.Results The expression of all the evaluated cancer/testis antigens were elevated in HOS and U2OS osteosarcoma cell lines after hypomethylating treatment with DAC.The proliferation of in vitro cultured osteosarcoma cells can be significantly suppressed after at least 5 d treatment with DAC.Besides,DAC alone controlled osteosarcoma cell proliferation.In immune deficient mouse models,hypomethylating pre-treatment resulted in successful T-cell homing to tumor sites.Moreover,the combination treatment with DAC and CTA specific T-cell adoptive transfer significantly suppressed tumor proliferation.In immune competent mouse models,hypomethylating treatment with DAC improved autologous T-cell infiltration into the tumor,and strengthened the activity of intratumoral CD8+ T-cells,elevated the secretion of IFN-gamma,granzyme B and perforin by CD8+ T-cells.Conclusion Hypomethylating treatment is able to suppress osteosarcoma cell proliferation,improve the expression of CTA in osteosarcoma cells,and consequently provide optimal environment for CTA specific T-cell adoptive therapy.

Objective To investigate the safety and efficacy of curettage and excision for giant cell tumor of the cervical spine.Methods Retrospectively analyzed 6 cases of giant cell tumors patients who underwent surgical resection of cervical spine between April 2006 and July 2015.There were 2 males and 4 females with an average age of 31.3 years old (ranged from 18 to 42 years).Among them,4 cases were located in C2 vertebral body,1 case located in C3 vertebral body,1 case in C4 spinous pro cess and vertebral lamina.In this study,all the 6 patients underwent intralesional surgery,3 patients were Enneking grade ⅡA,which 1 case underwent curettage,2 cases underwent extended curettage;three cases were Enneking grade ⅢB,which 1 case underwent extended curettage,and 2 cases underwent subtotal spondylectomy.Three patients received local inactivation of the lesion.One patient received local radiotherapy after first posterior occipital-cervical fixation,and underwent posterior and anterior tumor resection,bone grafting and internal fixation 3 months later.One patient was treated with denosumab preoperatively,3 patients were treated with bisphosphonates postoperatively.The neurological status was evaluated by Frankel classification pre-and postoperatively,the pain scale was evaluated by Visual Analogue Scale (VAS) pre-and postoperatively.Imaging examination was used to assess the location and the extent of the tumor preoperatively,as well as the tumor recurrence postoperatively.Results The mean follow-up period was 61.1 months (ranged from 25 to 134 months).One case underwent posterior surgery,while other 5 cases underwent anterior and posterior surgery;3 patients underwent one-stage surgery,3 patients underwent multi-staged surgery.The mean intraoperative bleeding was 2 142 ml (ranged from 300 to 9100 ml).The mean preoperative VAS score was 3 (ranged from 2 to 5),the neck pain of the patients were all relieved postoperatively,and the mean VAS score was 0.The Frankel grade were E in all 6 patients of pre-and postoperation.One intracranial epidural hematoma occurred on the second day after operation,emergency evacuation of hematoma was then performed and the postoperative recovery was good.At the latest follow-up,no internal fixation loosening or failure occurred,and no tumor recurrence was observed in all patients.Conclusion Intralesional curettage and excision of the cervical spinal giant cell tumor is a safe and effective surgical method which can achieve satisfactory local control and prognosis.

Objective To investigate the clinical charactistics,diagnosis,treatment options and surgical efficacy of spinal osteoblastoma.Methods From May 2007 to May 2016,the clinical manifestations,imaging data,diagnosis,treatment and prognosis of 11 patients with spinal osteoblastoma were retrospectively reviewed.There were 7 males and 4 females.The age ranged from 15 to 44 years old with the average of 27.5 years.Two lesions were involved in cervical spine and 6 lesions were located in thoracic spine.The other 3 cases was in lumbar spine.All patients suffered from local pain.Four patients had neurological deficiency,with 3 suffering radicular pain and 1 suffering incomplete paraplegia (Frankel C).Four patients were staged as Enneking 2 and treated by intralesional curettage.Seven patients were staged as Enneking 3.Accordingly,4 patients were treated by expanded excision with single posterior approach and 1 patient was treated by expanded excision with combined anterior and posterior approach.The other 2 patients were treated by piecemeal total vertebrectomy with single posterior approach.The pain release,neurological recovery and tumor recurrence were evaluated by postoperative follow-up.Results The mean operation time was 3.5 h (range,1.5-7 h) and the average intraoperative blood loss was 800 ml (range,100-3 000 ml).1 patient had cerebrospinal fluid leakage and 2 patients had pleural effusion.No surgical infection was detected in any patient.After surgery,the pain was dramatically relieved in all patients.The radicular pain in 3 patients were relieved and the incomplete paraplegia in 1 patient was recovered to Frankel E.The mean follow-up period was 45.8 months (range,12-117 months).Recurrence occurred in 1 case of cervical 7 and thoracic 1 spine leison 4 years after the surgery.Another expanded excision of the tumor was conducted for this patient and no recurrence was detected till now.No other cases of recurrence were observed.No loosing or breakage of implantation was detected during the follow-up.Conclusion For Enneking 2 leisons,intralesional curettage was effective.For Enneking 3 leisons,the expanded excision or piecemeal total vertebrectomy were recommended.No matter the excision was intralesional or not,the satisfactory results could be achieved if complete tumor excision could be conducted.

Objective:To analyze the surgical techniques, surgical indications and early clinical effects of 3D printed hemipelvic prostheses in the reconstruction of pelvic malignant tumors resected by the sacroiliac joint.Methods:From January 2016 to March 2020, a retrospective analysis of 9 patients with malignant tumors involving pelvis I+II or I+II+III region were treated with sacroiliac joint osteotomy and 3D printed pelvic prosthesis reconstruction. There were 7 males and 2 females; their age was 51.1±10.5 years (range 27-66 years). Among them, 5 cases were chondrosarcoma, 1 case was pleomorphic undifferentiated sarcoma, 2 cases were metastatic renal cell carcinoma, and 1 case was metastatic primitive neuroectodermal tumor. Resection of pelvic area I+II or I+II+III were according to the extent of tumor involvement. During the resection of pelvic I region, osteotomy was done through sacroiliac joint surface, and 3D printed hemipelvic prosthesis that fits the sacral auricular surface was used for reconstruction. Postoperative imaging examination was used to evaluate the acetabular rotation center deviation of the pelvic prosthesis; the International Bone Tumor Society (Musculoskeletal Tumor Society, MSTS) function score was used for functional evaluation; the patient's oncology outcome and postoperative complications were evaluated.Results:All 9 patients successfully completed the operation. The operation time was 3.5-6 hours, with an average of 4.5 hours. The intraoperative blood loss was 800-3 000 ml, with an average of 1 400 ml. 3 patients underwent resection and reconstruction of pelvis I+II area, 4 patients underwent pelvic resection and reconstruction of I+II+III area, 2 patients underwent pelvic I+II+III area combined with proximal femur resection and reconstruction; all patients were followed up. The follow-up time was 6-50 months, with an average of 16 months. At the last follow-up of 9 patients, the MSTS score was 12-26, with an average of 20.2; the postoperative rotation center horizontal displacement distance was 10.67±7.12 mm, and the vertical displacement was 8.56±4.22 mm. One case of metastatic cancer was found to have multiple metastases throughout the body during chemotherapy 3 months after surgery, and died in 7 months after surgery; 1 case of pelvic metastatic renal cell carcinoma developed multiple metastases within one and a half years after surgery, controlled by targeted drugs, and survived with the tumor; the rest seven cases had no recurrence at the surgical site and no distant metastasis was found.Conclusion:The semipelvic prosthesis with 3D printed auricular surface has potential advantages in reconstructing the bone defect of the pelvis I+II or I+II+III area after the sacroiliac joint osteotomy. The short-term efficacy is relatively satisfactory, and the long-term efficacy remains to be further observed.

The transportation of electron is inseparable from vacuum environment. The maintenance of the vacuum system of Elekta linear accelerator depends on two sputtering ionic pumps at the gun end and the target end. The traveling wave acceleration were used in Elekta linear accelerators. And the design of the electron gun filament is detachable. Because of these two reasons, the vacuum stability is relatively weak. Only two vacuum values are used to reflect the operation state of the whole vacuum system, which causes a few failures but will not trigger a the machine interlock. Considering the complexity of whole vacuum system, the problem of vacuum caused by the failure of various components in vacuum system is analyzed in this paper. It is hoped that some useful repairing experience and suggestions for the maintenance engineers of linear accelerator to solve the vacuum fault and rebuild the vacuum can be provided quickly.
Electrons ; Particle Accelerators ; Radiotherapy Dosage ; Vacuum

Objective:To explore the clinical characteristics of dislocation after resection and reconstruction of tumors involving pelvic area II, and to try to propose intraoperative and postoperative techniques to prevent its occurrence.Methods:From March 2011 to March 2021, 122 patients with resection and reconstruction involving pelvic area II were retrospectively analyzed. Among them, 17 had postoperative dislocation, 32 had pelvic area II, and 31 had pelvic area I+II. There were 40 cases in the pelvic area II+III, and 19 cases in the pelvic area I+II+III. There were 49 female patients and 73 male patients; the mean age was 47 years (9-73 years). The Musculoskeletal Tumor Society (MSTS) score of lower extremity patients after reduction was evaluated, and the clinical characteristics of dislocation, such as dislocation direction, dislocation time and reduction method, were counted and analyzed, and feasible prevention measures were analyzed based on the imaging characteristics after resection and reconstruction. dislocation method.Results:Among the 122 patients, there were 17 cases of dislocation, and the dislocation rate was 13.7%. Among them, 12 cases were anterior dislocation, accounting for 70.6% of anterior dislocation; 5 cases were posterior dislocation, and the proportion of posterior dislocation was 29.4%, difference (χ 2=4.52, P=0.033). There were 12 cases of dislocation within 3 months after operation, accounting for 70.6%; 1 case of dislocation occurred in 5 months after operation, and the other 4 cases of dislocation occurred for more than one year. The MSTS score of the dislocation patients after reduction was 56.1±15.6% (20%-80%). Combined with postoperative imaging examinations, the feasible methods for preventing dislocation include: The anteversion angle of the acetabular cup can be appropriately reduced (0°-10°); The acetabular cup can be appropriately shifted to the rear of the rotation center; Appropriately reducing the anteversion angle of the femoral neck prosthesis, the combination of the three can reduce the occurrence of femoral-acetabular prosthesis impingement; at the same time, the affected limb is controlled in a neutral position with strict nail shoes after surgery to avoid the occurrence of external rotation. Conclusion:The dislocation after tumor resection and reconstruction in pelvic area II is mostly anterior dislocation. Postoperative CT scan of the pelvis shows that the space between the neck of the femoral stem prosthesis and the lower edge of the acetabulum is small, which is prone to impingement. If the anteversion angle of the acetabular cup is appropriately reduced, the acetabular prosthesis is appropriately displaced posteriorly, and the anteversion angle of the femoral neck is reduced by 5°, the possibility of femoral-acetabular impingement can be reduced, thereby reducing the risk of postoperative dislocation.

Objective:To investigate the surgical method and clinical effect of O-arm navigation mini-open burring for osteoid osteoma.Methods:Eighteen patients with osteoid osteoma were treated with O-arm guided grinding drill from June 2021 to May 2022, including 15 males and 3 females, the age was (18.4 ±10.9) years (range 2 to 44 years), and the course of disease ranged from 1 week to 3 years (mean 14.2 months). The lesions sites included 6 cases of proximal femur, 3 cases of distal femur, 4 cases of proximal tibia, 1 case of distal tibia, 2 cases of proximal fibula and 1 case of distal and proximal humerus. During the operation, the O-arm navigation was used to determine the location of the focus, the muscle and soft tissue was peeled off to the bone surface through a 1-4 cm small incision, the channel retractor was placed, and the burr was registered as a navigation recognition device to gradually remove the bone on the surface of the tumor nest, and the tumor nest was scraped with a curette for pathological examination; according to the navigation image, the focus was enlarged removed with burr and the grinding range was confirmed by the O-arm X-ray machine before the end of the operation. The patients were followed up for 6 to 15 months (mean 9.5 months). CT scans were performed before and after surgery for imaging comparison in order to figure out whether it had residual lesions or recurrence. The visual analogue score (VAS) of pain was used as a parameter for evaluating the clinical efficacy.Results:The operation time of 18 cases was 40-175 min, with an average of 89.3 min. The time required to establish navigation image was 18.0 ±4.1 min (range 13 ~ 22 min). The length of the incision was 2.7±1.1 cm (range 1-4 cm). All patients achieved complete curettage of the lesions, and osteoid osteoma was confirmed by pathology after operation. All the patients could move to the ground 24 hours after operation, and the pain was significantly relieved from 3 to 7 d after operation, and the pain almost disappeared 3 months after operation. The VAS score of 18 cases was 5.33±1.24 before surgery, 2.79±1.32 on the 3rd day, 1.86±1.21 on the 7th day, 0.86±0.93 on the 1st month, 0.33±0.48 on the 3rd month, and 0.09±0.29 on the 6th month after operation, and the difference was statistically significant ( F=58.50, P<0.001). There were no serious complications during and after operation, and the success rate of treatment (no recurrence of symptoms, no residual recurrence of imaging lesions, no serious complications after operation) was 100%. Conclusion:Treatment of osteoid osteoma with mini-open excision using burrs under the navigation of O-arm is a simple, safe, minimally invasive and efficient technique. Intraoperative precise positioning and the use of burr with navigation to remove a larger area than the tumor nest are the keys to successful treatment.