Objective To compare the dosimetry between inversely optimised intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy using the field-in-field technique (FIF) for whole-breast radiotherapy with a boost to the tumor bed after breast-conserving surgery.Methods IMRT and FIF treatment plans were respectively performed and optimised for 9 patients with early stage leftbreast cancer after breast-concerving surgery.The prescribed dose of breast was 50.4 Gy in 28 fractions,1.8 Gy per fraction and that of tumor bed was 61.6 Gy in 28 fractions,2.2 Gy per fraction.The conformity index,the dose and volume for OAR( organs at risks),time of planning and treatment for the two plans were compared.Results The conformity index(CI) for IMRT was improved compared with the FIF in breast [(1.82±0.16) vs.(2.21±0.15)] and tumor bed [(1.19±0.04) vs.(1.59±0.11),t=2.08,3.97,P ＜ 0.05 ].There was no difference for V20 of ipsilateral lung and V30 of heart between two plans.The Dmax and Dmean of the contralateral lung of FIF were (5.41 ±2.76) and (0.51 ±0.10) Gy,lower than those of IMRT [ (25.72 ± 2.61 ) and (7.46 ± 0.39) Gy,t =-22.44,- 21.14,P ＜ 0.05 ].The Dmax and Dmean of the contralateral breast of FIF were (8.50 ± 5.61 ) and (0.47 ± 0.11 ) Gy,lower than those of IMRT [(27.73±4.30) and (6.38±0.48) Gy,t=-5.66,-14.83,P＜0.05].ForFIF,theV5of the contralateral lung and breast were (0.09 ± 0.09) ％ and (0.45 ± 0.45 ) ％,respectively,lower than those of IMRT,which were (84.66 ±3.06) ％ and (60.79 ±4.94)％ (t =-28.19,- 12.80,P＜0.05).The time of optimised plan was (61.57 ± 0.89) min for FIF and(241.28 ± 1.06) min for IMRT (t=-32.35,P＜0.05),and that of treatment were (16.14±1.42) min for FIF and (29.85 ±0.59) min for IMRT (t =- 8.82,P ＜ 0.05).Conclusions For patients with early stage breast cancer after breast-concerving surgery,IMRT could improve the conformity index of target but increase the dose of eontralateral lung and breast.However,FIF has advantage on the time of optimising plan and treatment.

Objective To investigate the difference of apparent diffusion coefficients (ADCs) changes in three major salivary glands after gustatory stimulation using two different stimuli. Methods Thirty healthy volunteers were examined with a 1.5 T MR unit. A diffusion-weighted MR imaging (MR DWI) sequence was performed once at rest and continuously repeated 13 times after gustatory stimulation using a commercially available lemon juice and vitamin C tablets in the same volunteer by using self-controlled method. The subsequence of two stimuli was random. In addition, the salivary flow rates at rest and after stimulation were measured. Characteristics and differences in ADCs curves of three salivary glands before and after stimulation between two stimuli were analyzed. Comparison of maximum ADCs, maximum ADCs increase rates (IRs) and times to maximum ADCs(Tmax) between two stimuli was performed by using independent-samples t test. Correlation analysis between rest salivary flow rates and rest ADCs, the maximum salivary flow rates and ADCs after stimulation, the maximum salivary flow IRs and ADC IRs after stimulation were performed by using Pearson correlation test. Results In lemon juice stimulation group, the mean ADCs mostly showed a steady increase to peak values during the first DW MRI scan after stimulation in all glands, followed by a gradually decrease fluctuating slightly around the baseline values. In vitamin C stimulation group, the mean ADCs were significantly increased in all glands during the first DW MRI scan after stimulation, followed by a gradual upward trend till peak values. In lemon juice stimulation group, the mean Tmax of submandibular and sublingual glands[(184±122)s, (345±232)s, respectively] were significantly earlier than those[(454 ± 301)s, (528 ± 297)s, respectively] in vitamin C stimulation group (t=-3.517 and-2.548 respectively, P<0.01 for all). The mean maximum ADCs of three glands in lemon juice stimulation group[(1.05 ± 0.12) × 10-3 mm2/s, (1.22 ± 0.10) × 10-3 mm2/s and (1.26 ± 0.21) × 10-3 mm2/s, respectively] were all lower than those in vitamin C stimulation group[(1.13±0.13) ×10-3 mm2/s, (1.32±0.25) × 10-3 mm2/s and (1.57 ± 0.36) × 10-3 mm2/s, respectively], and the differences in parotid and sublingual glands between two groups were significant(t=-2.894 and-3.681 respectively, P<0.01 for all). The mean maximum ADC IRs of three glands in lemon juice stimulation group[(11.35±4.07)%, (8.81±5.40)%, (34.08±21.66)%, respectively] were significantly lower than those[(17.80 ± 12.72)%, (18.16 ± 18.93)%, (67.49 ± 46.04)% , respectively] in vitamin C stimulation group (t=-2.252,-2.330 and-3.432 respectively, P<0.05 for all) . In two groups, the mean maximum ADC IRs of parotid and submandibular gland were all significantly lower than sublingual gland (t=-5.994 and-6.443 respectively, P<0.01 for all). No correlation was observed between ADCs and salivary flow rates, ADC IRs and salivary flow rate IRs in two groups (P>0.05). Conclusion MR DWI with transient stimulation using lemon juice is more stable for evaluating the physiologic changes of salivary glands in vivo.

Objective: To evaluate the precision of image registration between MRI simulation (MRIsim) and CT simulation compared to diagnostic MRI(MRIdiag) and to provide information for further application of MRIsim. Methods: A total of 24 patients who underwent both MRIsim and MRIdiag were enrolled, including 8 patients with gliomas, 8 with nasopharyngeal carcinomas and 8 with prostate cancers. MRIsim and MRIdiag images of each patient were fused with CT. The OARs were delineated on three modalities of images and targets were delineated on fusion image of MRIsim with CT (F_CTMsim) and fusion image of MRIdiag with CT (F_CTMdiag) respectively. The concordance index (CI), Dice′s similarity coefficient (DSC) between the OARs and image similarity index (S) based on images from MRIsim, MRIdiag and CT were evaluated. IMRT plans were designed based targets on F_CTMsim and OARs on CT images, and differences in dosimetry of targets and OARs were evaluated subsequently. Results: Volumes of most OAR from three modalities of images showed no statistically significant difference(P>0.05). All the CI and DSC between the OARs derived from MRIsim and CT were higher than those corresponding values from MRIdiag, and a statistically significant difference was achieved in 50% of these OARs (t=2.58-5.47, P<0.05). The S values of MRIsim and MRIdiag compared with CT were 0.89 and 0.83 respectively (t=5.77, P<0.05). MRIsim improved the S value by 10% (2%-56%) compared with MRIdiag. No further differences in dosimetry were found on all OARs and all targets(P>0.05). Conclusions The precision of image registration can be significantly improved by introducing MRIsim into radiotherapy planning design compared with MRIdiag. However, no significant differences in dosimetry were found on targets produced by rigid registration and manual adjustment method .

Objective To explore the effects of various radiation doses on the NFAT3/c4 signaling pathway and the improvement effect of exogenous brain-derived neurotrophic factor(BDNF)on this pathway. Methods Four groups of one-month-old Sprague-Dawley rats received radiation doses of 0,2,10,and 20 Gy, respectively, in a single radiation. At three days after radiation, exogenous BDNF was injected stereotaxically into the bilateral hippocampus. Western blotting and RT-PCR were used to assess the levels of NFAT3/c4-related proteins in the hippocampus. Results The results of Western blotting and RT-PCR showed that the level of NFAT3/c4 was reduced in a dose-and time-dependent manner after ionizing radiation. Compared with the radiation alone group,the ionizing radiation plus BDNF group had significantly increased levels of NFAT3/c4 and CaN with increases in radiation dose and time. Conclusions Whole brain radiotherapy inhibits the CaN/NFAT3/c4 signaling pathway. Exogenous BDNF can promote the NFAT-dependent transcription and then improve the cognitive function.

This paper studies the active force characteristics of the neck muscles under the condition of rapid braking, which can provide theoretical support for reducing the neck injury of pilots when carrier-based aircraft blocks the landing. We carried out static loading and real vehicle braking experiments under rapid braking conditions, collected the active contraction force and electromyography (EMG) signals of neck muscles, and analyzed the response characteristics of neck muscle active force response. The results showed that the head and neck forward tilt time was delayed and the amplitude decreased during neck muscle pre-tightening. The duration of the neck in the extreme position decreased, and the recovery towards the seat direction was faster. The EMG signals of trapezius muscle was higher than sternocleidomastoid muscle. This suggests that pilots can reduce neck injury by pre-tightening the neck muscles during actual braking flight. In addition, we can consider the design of relevant fittings for pre-tightening the neck muscles.
Neck Muscles ; Neck ; Electromyography ; Head

Objective:To explore the effects of interpregnancy interval (IPI) on pregnancy outcomes of subsequent pregnancy.Methods:A multicenter retrospective study was conducted in 21 hospitals in China. Information of age, height, pre-pregnancy weight, IPI, history of diseases, complications of pregnancy, gestational age of delivery, delivery mode, and pregnancy outcomes of the participants were collected by consulting medical records of pregnant women who had two consecutive deliveries in the same hospital during 2011 to 2018. The participants were divided into 4 groups according to IPI:<18 months, 18-23 months, 24-59 months and ≥60 months. According to the WHO′s recommendation, with the IPI of 24-59 months group as a reference, to the effects of IPI on pregnancy outcomes of subsequent pregnancy were analyzed. Stratified analysis was further carried out based on age, history of gestational diabetes mellitus (GDM), macrosomia, and premature delivery, to explore the differences in the effects of IPI on pregnancy outcomes among women with different characteristics.Results:A total of 8 026 women were included in this study. There were 423, 623, 5 512 and 1 468 participants in <18 months group, 18-23 months group, 24-59 months group and ≥60 months group, respectively. (1) The age, pre-pregnancy body mass index (BMI), history of cesarean section, GDM, gestational hypertension and cesarean section delivery rate of <18 months group, 18-23 months group, 24-59 months group and ≥60 months group were gradually increased, and the differences were statistically significant ( P<0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 24-59 months group, the risk of premature delivery, premature rupture of membranes, and oligohydramnios were increased by 42% ( OR=1.42, 95% CI: 1.07-1.88, P=0.015), 46% ( OR=1.46, 95% CI: 1.13-1.88, P=0.004), and 64% ( OR=1.64, 95% CI: 1.13-2.38, P=0.009) respectively for women in the IPI≥60 months group. No effects of IPI on other pregnancy outcomes were found in this study ( P>0.05). (3) After stratified by age and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of oligohydramnios for women with advanced age ( OR=2.87, 95% CI: 1.41-5.83, P=0.004); and <18 months could increase the risk of premature rupture of membranes for women under the age of 35 ( OR=1.59, 95% CI: 1.04-2.43, P=0.032). Both the risk of premature rupture of membranes ( OR=1.58, 95% CI: 1.18-2.13, P=0.002) and premature delivery ( OR=1.52, 95% CI: 1.07-2.17, P=0.020) were significantly increased in the IPI≥60 months group. After stratified by history of GDM and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would lead to an increased risk of postpartum hemorrhage for women with a history of GDM ( OR=5.34, 95% CI: 1.45-19.70, P=0.012) and an increased risk of premature rupture of membranes for women without a history of GDM ( OR=1.44, 95% CI: 1.10-1.90, P=0.009). After stratified by history of macrosomia and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months could increase the proportion of cesarean section for women with a history of macrosomia ( OR=4.11, 95% CI: 1.18-14.27, P=0.026) and the risk of premature rupture of membranes for women without a history of macrosomia ( OR=1.46, 95% CI: 1.12-1.89, P=0.005). After stratified by history of premature delivery and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of premature rupture of membranes for women without a history of premature delivery ( OR=1.47, 95% CI: 1.13-1.92, P=0.004). Conclusions:Both IPI≥60 months and <18 months would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women of reproductive age to maintain an appropriate IPI when they plan to pregnant again, to reduce the risk of adverse pregnancy outcomes in the subsequent pregnancy.

After multidisciplinary treatment including radiotherapy, the median survival of patients with glioblastoma multiforme (GBM) remains approximately 1 year. The heterogeneity of the genome and proteome of glioblastoma stem cells (GSC) is the fundamental factor affecting the prognosis. Proteomics-based sensitization of key radioresistance proteins is expected to improve the prognosis of GBM patients. In this article, literature review was conducted from PubMed and other databases in the previous 10 years to systematically discuss the research progress on various commonly used protein quantitative techniques, tools for data processing analysis and the application in radioresistance and radiosensitization of GSCs.