Background and purpose:As a new and important radiotherapy technique,intensity-modulated radiation therapy(IMRT) has been widely used in the clinic,but it requires longer time to deliver for one treatment session.The purpose of this study was to investigate the radiobiological effects of CNE and A549 cell lines irradiated by IMRT model.Methods:Part Ⅰ:The radiobiological characteristics of CNE and A549 cell lines were studied with standard clonogenic assays,using standard liner-quadratic model and incomplete repair model to fit the dose-survival curves.Part Ⅱ:a total dose of 8 Gy was given in two fractions with different interfraction intervals to compare the differences of cell surviving fractions(SF).Part Ⅲ:fractionated irradiation of 2 Gy,2 Gy?2,2 Gy?3,2 Gy?4 were given with one fraction per day simulating clinical dose-time-fractionation pattern in 2,20 and 40 min per fraction,respectively.Results:The ?/? of CNE and A549 was 1.76 and 12.41 Gy,respectively;the cell surviving fractions increased when the interfraction interval was longer,The values of SF2 were 0.0237 and 0.0243 in 2 min irradiation group,0.0304 and 0.0296 in 20 min irradiation group,and increased to 0.0378 and 0.0359 in 40 min irradiation group,respectively.Conclusion:The prolonged fraction delivery time would significantly decrease theradiobiological effects,it is strongly recommended that the delivery time be kept as short as possible,or do appropriate dose compensation.

BACKGROUNDRecently, results from IALT, JBR10 and CALGB9633 showed that postoperative adjuvant chemotherapy improved survival rate of patients with non-small cell lung cancer (NSCLC) after complete resection. The aim of this study is to evaluate the effect of postoperative adjuvant chemotherapy on survival after complete resection for stage IIIA-N2 NSCLC.

METHODSFrom Jan 1999 to Dec 2003, one-hundred and fifty patients with stage IIIA-N2 NSCLC were randomly divided into two groups. The chemotherapy group received four cycles of chemotherapy with navelbine or paclitaxel plus carboplatin, while the observation group did not receive chemotherapy after operation.

RESULTSIn the chemotherapy group, 86.1% (68/79) of patients finished 4 cycles of chemotherapy, and no one died of toxic effects of chemotherapy; 25% of patients had grade III-IV leukopenia, 2% of patients had febrile leukopenia. The median survival time for the entire 150 patients was 879 days, and 1-, 2- and 3-year survival rate was 81%, 59% and 43%. There was no significant difference in median survival between the chemotherapy and observation groups (P= 0.0527), but there was significant difference in the 1- and 2-year survival rate (94.71% and 76.28% vs 88.24% and 60.13%, P < 0.05). The most common site of recurrence was the brain. Twenty-six percent (39/150) of patients recurred in the brain as their first site of failure, and 22.8% (18/79) for the chemotherapy group, 29.6% (21/71) for the observation group. The median survival time for patients who developed brain metastasis was not significantly different between the chemotherapy and observation groups (812 days vs 512 days, P=0.122), but there was significant difference in the 2-year survival rate (66.7% vs 37.6%, P < 0.01). The median survival was 190 days for the patients since brain metastasis appeared.

CONCLUSIONSPostoperative adjuvant chemotherapy dose not significantly improve median survival among patients with completely resected stage IIIA-N2 NSCLC, but significantly improves the 1- and 2-year survival rate. It also dose not decrease the incidence of brain metastasis but puts off the time of brain metastasis.

Objective To study the correlation between the changes of serum neuron specific enolase (NSE) level and psychological statuses in patients with cerebral concussion.Methods Forty patients with cerebral concussion,admitted to our hospital from January 2012 to December 2012,were chosen in our study as experimental group,and other 40 healthy controls performed physical examination in our Physical Examination Center at the same period were chosen.The serum NSE level in the two groups was determined by enzyme-linked immunosorbent assay (ELISA); Symptom Checklist 90 (SCL-90) scale was performed in 40 patients at different times after injury,and these data were compared with those from the national norm; the correlation between the changes of serum NSE level and SCL-90 scores was analyzed.Results The serum NSE level in the experimental group 1 d after the injury was obviously higher than that in the control group (P＜0.05); 3 and 7 d after the injury,the serum NSE level in the experimental group was close to normal level,which showed no significant differece as compared with that in the control group (P＞0.05).The SCL-90 scores in the experiemtal group 1,3 and 7 d after injury was signficantly higher than that of the national norm (P＜0.05).Positive corelation was noted between serum NSE level and SCL-90 scores 1 and 3 d after injury (r=0.498,P=0.001; r=0.418,P=0.007);however,negative corelation was noted btween the two 7 d after injury (r=0.213,P=0.186).Conclusion Different corelation can be noted between serum NSE level and SCL-90 scores at different time points;combined application of serum NSE level and SCL-90 scores can promote the diagnosis and treatment of patients with brain concussion.

Objective To investigate the psychological status of patients with brain concussion. Methods A total of 186 patients with brain concussion were evaluated using Symptom Check-List 90 (SCL-90) and the scores were compared with the norms. Results The general scores (137.71±39.48), total mean scores (1.53±0.44) and positive object number (32.90±19.41) of SCL-90, as well as the factor scores ofsomatization(1.57±0.52), compulsion(1.79±0.50), anxiety disorder(1.50±0.49), hostility(1.63± 0.57), phobic anxiety(1.57±0.51), paranoid ideation(1.62±0.51) and psychoticism ( 1.49±0.43) in the patients with brain concussion were all higher than the normal ones (129.96±38.76, 1.44±0.43, 24.92± 18.41, 1.37±0.48, 1.62±0.58, 1.39±0.43, 1.48±0.56, 1.23±0.41, 1.43±0.57, 1.29±0.42, respectively)(P< 0.05). The scores of interpersonal sensitivity (1.67±0.54) were also significantly higher than that of normal (P>0.05). Conclusion Brain concussion may lead to psychological disturbance, for which early interventions should be administered.