Objective To examine the interfractional dosimetric variations among inverse three-dimensional (3D) plan, forward 3D plan, and two-dimensional (2D) plan of intracavitary brachytherapy for cervical cancer, and to discuss the risk of implementing the interval plan on different implantation applicators at short time intervals.Methods Twenty-five groups of CT-guided intracavitary brachytherapy (two consecutive radiations at ≤4 d apart) plans from 11 cervical cancer patients who received radical radiation therapy in our hospital were reviewed and compared.The dwelling location and time of the first intracavitary brachytherapy plan (Plan-1) were simulated on the CT image of the second intracavitary brachytherapy to form Plan-1-S.The target coverage indices and D 2 cc of organs at risk (OARs) of Plan-1-S and Plan 2(actual plan of the second intracavitary brachytherapy) under the three planning modes were recorded and compared using the paired t-test, Wilcoxon signed rank test, and ANOVA.Results The D90, D100, and V100 of high-risk CTV were significantly lower in Plan-1-S created under the inverse mode in the actual plan (-9.11±13.46%,-13.16±18.79%, and-7.80±13.34%, P=0.002, 0.002, and 0.005, respectively).D90, D100, and V100 of the interval plan had the greatest reduction under the inverse mode (76%, 80%, and 76%, respectively).The maximum reductions in D90, D100, and V100 were 332.14 cGy (2D), 244.12 cGy (forward), and 41.76%(inverse).OAR overdose occurred most frequently under the forward mode;the rates of D90, D100, and V100 reductions accompanied by one OAR overdose were 29.41%, 37.50%, and 25.00%, and the rates of D90, D100, and V100 reductions by two OAR overdoses were 5.88%, 12.50%, and 6.25%,respectively.Overdose occurred most frequently in the small intestine (36%).Comparison of the three planning modes showed that the inverse plan had a greater reduction in each target coverage index than the 2D plan.Conclusions The simulated interval plan can significantly reduce target coverage and increase the risk of OAR overdose regardless of the planning mode and the short time intervals, and is therefore not recommended for clinical application.

Objective To explore the differences between schizophrenic patients and normal at prospective memory,and investigate the effect of personality intermediary between schizophrenia and prospective memory.Methods A case-control study was utilized in this research.It used the color matching task to test prospective memory and MMPI-2 scale to test personality differences between the two groups.Results Schizophrenia prospective memory score(19.29±2.30),lower than the normal group(44.74±2.06),the difference was significant(P＜0.01).In mediating effect on the personality inspection,the subscales within MMPI-2 of Social Scale(Si) and Anxiety and tension Scale(ANX) regression coefficients were tested(P＜0.05),which showed significant effect.Further analysis with sobel statistics showed that only one factor tested was significant.The test coefficients of depression scale (D),mental weakness scale (Pt) and schizophrenia scale (Sc) were significantly different (P＜ 0.05),which showed that these subscales also had significant mediating effect.Conclusion The prospective memory performance is low in schizophrenia.The personality characteristics that depression,mental weakness,schizo phrenia,social anxiety and tension play an intermediary role in schizophrenia and prospective memory.

Objective To compare the difference of prospective memory(PM) between schizophrenia patients and normal people,and to analyze the internal component of prospective memory using multinomial processing tree(MPT) model.Methods 17 schizophrenia patients and 17 age-and education-matched control participants completed an event-based PM task which was embedded within an ongoing computer-based color-matching task.Internal component of prospective memory was analyzed using multinomial processing tree(MPT) model.Results The scores of prospective memory performance in schizophrenia patients and normal controls were (21.83± 2.46) ％ and (38.81±2.26) ％, and the difference was statistically significant (t=2.11, P＜0.05).The difference of ongoing task between schizophrenia patients ((75.88±0.43) ％) and controls ((71.44±0.45) ％) was statistically significant (t=2.79, P＜0.05).The reaction time of schizophrenia patients was significantly longer than that of normal controls((2.34±1.41) s vs (1.81± 1.19) s, t=11.24, P＜ 0.05).The MPT model revealed a significant group difference in the prospective component (0.82 vs 0.97, G2(1)=14.17, P＜ 0.01) and retrospective component (0.54 vs 0.41 ,G2(1) 14.17, P＜0.01).Conclusion The prospective component of event-based prospective memory of schizophrenia patients was lower than normal controls,which may result in the impairment of PM performance.

Objective To investigate the treatment outcomes of 41 patients with suprasellar and pineal germinoma who are treated in our department in recent 18 years,and to explore related therapeutic strategies.Methods A total of 41 patients with concurrent suprasellar and pineal germinoma who were treated in our department from January 1996 to August 2013 were enrolled.There were 35 male patients and 6 female patients,and the median age was 16 years (range 5-39 years).Five patients had pathologically confirmed germinoma and 36 patients had clinically diagnosed germinoma.Conventional radiotherapy was performed for 33 patients, and intensity-modulated radiotherapy was performed for 8 patients.Combined-modality chemoradiotherapy was performed for the 5 patients with pathologically diagnosed germinoma.The 6 MV X-ray was applied for radiotherapy;6 patients received whole ventricular irradiation and a boost in tumor region, 16 received whole-brain radiotherapy and a boost in tumor region,and 19 received craniospinal irradiation and a boost in tumor region.The median radiation dose for tumor region was 45.0 Gy (37.8-50.0 Gy),and the median dose for prophylactic irradiation was 25.0 Gy (17.8-35.0 Gy).The survival was caculated using Kaplan-Meier method.Results The number of patients followed were 26 at 5-years.The 5-year overall survival rate and relapse-free survival rate were 95% and 85%,respectively.Relapse and metastasis were noted in 8 patients,and 3 of them died.There were 4 patients with spinal cord metastasis,1 patient with ventricular dissemination,and 3 patients with periventricular relapse.Among the 22 patients who did not undergo spinal irradiation,4(18.2%) experienced spinal cord metastasis,and all the other 19 patients who underwent spinal irradiation did not experience spinal cord metastasis.The 8 patients undergoing intensity-modulated radiotherapy and the 5 patients undergoing combined-modality chemoradiotherapy did not experience treatment failure during follow-up.Conclusions Radiotherapy for intracranial germinoma has a good therapeutic effect,and the patients with suprasellar and pineal germinoma who do not undergo spinal cord irradiation have a high failure rate.It is suggested to perform spinal cord irradiation for patients with suprasellar and pineal lesions.

Objective To investigate the associations between lifestyle factors and social network and cognitive impairment among the elderly in three communities in China.Methods From November 2017 to May 2018,1 200 elderly individuals were selected from three Chinese communities (Beijing,Hefei,and Lanzhou) using a random cluster sampling method.Data were collected on lifestyle,social network,and cognition.A conditional logistic regression analysis was conducted to identify the associations between lifestyle and social network and cognitive impairment.Results A total 1 115 participants (92.9％) were administered both social network and cognition questionnaires.After adjustment by age,sex,education,marital status,health,and living status,only low participation in physical activity was found to be associated with cognitive impairment (OR=0.65,95％ CI=0.45-0.93,P=0.019).A larger social network (OR=0.50,95％ CI=0.29-0.85,P=0.010),especially more friends (0R=0.44,95％ CI=0.29-0.65,P＜0.001),may decrease the risk of cognitive impairment.The interactions between lifestyle factors and social network were not associated with cognitive impairment.Conclusion Our findings suggest that larger social networks and physical activity are associated with cognitive function among the elderly.Identification and intervention of risk factors are crucial in the delay and prevention of cognitive impairment and the improvement of quality of life among the elderly.

Objective: To investigate the clinical features and prognosis of primitive neuroectodermal tumor (PNET). Methods: The clinical data of 99 patients with PNET from February 1, 1998 to February 1, 2017 were retrospectively analyzed. Univariate analysis was performed using Kaplan-Meier and Log rank test. Multiviate Cox regression was applied to analyzed independent prognostic factor for patient survival. Results: Among the 99 patients, 81 were peripheral PNET(pPNET) and 18 were central PNET (cPNET) . Biopsy was performed exclusively in 16 cases, with R0 resection in 61 cases, with R1 resection in 4 cases, and with R2 resection in 18 cases. Twelve patients underwent surgery only, nine had chemotherapy only, and one received radiotherapy only. There were 72 patients who had combined treatment including chemotherapy, and 48 patients had combined therapy including radiotherapy. The one-year, three-year and five-year overall survival(OS) rates of the 99 PNET patients were 79.2%, 63.9% and 56.1% respectively, and median OS time was 14.0 months. The one-year, three-year and five-year progression free survival (PFS) rates of these patients were 42.7%, 25.7% and 19.8% respectively, and median PFS time was 8.0 months. The univariate analysis revealed that lymph node metastasis, surgical resection, numbers of cycles of chemotherapy and radiotherapy dose were the main factors affecting the OS (all P<0.05). Gender, age, lymph node metastasis, staging, and chemotherapy cycles were related to PFS in PNET patients (P<0.05). Multivariate analysis showed that the degree of surgical resection, chemotherapy cycle, and radiotherapy dosage were independent influencing factors of OS in PNET patients (risk ratio=1.856, 0.398, and 0.408, respectively, all P<0.05), and gender was an independent factor influencing PFS in PNET patients (risk ratio=0.494, P<0.05). Conclusions Comprehensive therapy is the main therapy for PNET patients. The surgical resection, cycles of chemotherapy and radiotherapy dosage are independent prognostic factors for patient′s OS.