Objective To measure and calculate the dose distribution (tissue absorbed dose) of mouth floor area while using 125I to treat sublingual gland carcinoma.Methods Phantom of head and neck was used to place the 125I radioactive seeds to simulate the sublingual gland carcinoma treatment.125I radioactive seeds of 29.6 and 25.9 MBq per seed were used as two groups,with 31 seeds in each group,and prescribed dose (peripheral matched dose) was 120 Gy.Thermoluminescence dosimetry (TLD) was used to measure the absorbed dose value in the simulated target and adjacent area.Gafchromic Eriochrome Black T (EBT) film was used to draw the dose distribution curve.Results Dose absorbed in the target area,target area center and the adjacent area one centimeter away from target reached 160 Gy,390-500 Gy,and 90-170 Gy,respectively.Dose of the skin ranged from 25 to 81 Gy,dose of mandible ranged from 7.9 to 67 Gy.No radiation cold spot was found.Conclusions 125I seeds could achieve an effective therapeutic dose distribution of the target area for sublingual gland carcinoma.Dose absorbed in the adjacent tissue is under safety limit.The radiation dose at mandible is lower,reducing the possibility of radiation damage to the bone.

Objective To evaluate the feasibility of individual template assisting permanent interstitial brachytherapy for skull base region.Methods From August 2010 to June 2012,20 patients with recurrent malignancies of skull base region received 125I seed permanent implantation.Before implanting,all patients underwent CT scan,the data were stored in Dicom format and imported into brachytherapy treatment planning system (BTPS).The preplan were finished by BTPS.Then,the digital model based on virtual needle and skin CT slices was reconstructed by Mimics and Geomagic.According to the digital model,the individual template was made from medical light-cured resin using rapid forming machine.During implanting,needles were inserted under the individual template assistance and 125I seeds were implanted according to preplan.After implanting,implantation quality was evaluated by 2D and 3D CT images and BTPS.The needles and seed distribution were observed.The actual dose distribution of target volumes D90,V100 and V150 was calculated.The complications were recorded within 72 hours.Results Interstitial implantation of 20 patients were performed successfully and efficiently under the individual template assistance without serious complications.Because of containing the virtual needle positioning and face surface feature information at the same time,the individual template significantly improved precision of needle location and orientation.The actuarial median number of 125I seeds implanted was 70 (range,20-172),and actuarial median D90,V100 and V150 was 181.6 Gy (127.4-279.6 Gy),98.2％ (94.6％-100％),43.2％ (24.3％-52.2％),respectively.The seed distribution and dosimetric quality were well controlled.Conclusions The method of individual template assisting permanent interstitial brachytherapy for skull base region is feasible,which can improve the accuracy of needle position placement.

Background There remains some controversy over whether polypoidal choroidal vasculopathy (PCV) represents a subtype of neovascular age-related macular degeneration (nAMD).Anti-vascular endothelial growth factor (VEGF) therapies are important in the treatment of PCV and nAMD.It has been identified that VEGF-A was differentially spliced from exons 8 and formed two isoforms families:the pro-angiogenic VEGFxxx family and the anti-angiogenic VEGFxxxb family.However,the role of the two VEGF families in PCV and nAMD was still unclear.Objective This study was to measure the contents of pro-angiogenic VEGFxxx family and the anti-angiogenic VEGFxxxb family in aqueous humor of nAMD and PCV patients and explore their effect on nAMD and PCV.Methods Thirty-four nAMD patients and 26 PCV patients were enrolled in Peking University People's Hospital during March to December,2013,and 16 age-related cataract patients served as controls.The aqueous humor samples 0.1 ml was collected before the introvitreous injection of anti-VEGF drug.The contents of pro-angiogenic VEGFxxx family and the anti-angiogenic VEGFxxx b family in the aqueous humor were measured by enzyme-linked immunosorbent assay(ELISA).Results The concentrations of VEGF in the aqueous humor in the nAMD group,PCV group and control group were (4 210.00±998.40),(387.00±51.31) and (377.40 ±69.97)pg/ml,respectively,showing a significant difference among the three groups (F =12.851,P =0.000).The concentrations of VEGF165 b in the aqueous humor in the nAMD group,PCV group and control group were (205.50±12.59),(159.40±16.25) and (347.90±29.18) pg/ml,with a significant difference among them (F=23.752,P=0.000).Compared with the control group,VEGF content in the aqueous humor was elevated and the VEGF165b content was declined in the nAMD group,and VEGF165b was lowed in the PCV group,with significant differences between them(all at P=0.000).However,no significant difference was seen in the change of VEGF between the PCV group and the control group (P=0.992).The VEGF content in the aqueous humor was higher in the nAMD group than that in the PCV group (P =0.001),but VEGF165b content was insignificantly different (P =0.097).Conclusions The downregulation of VEGFxxx b may be associated with nAMD and PCV.The different role of VEGFxxx b in the development of PCV and nAMD needs to be verified in further studies.

Background How to control progression of myopia is a central issue in clinical optometry.Some clinical trials showed that wearing base-in (BI) prism can slow down progression of myopia to certain degree.However,whether BI prism or base-out (BO) prism should be used is worth discussing.Objective This study was to investigate the influences of different prisms on accommodative response and microfluctuation in emmetropias.Methods This clinical trail was approved by Ethic Committee of Peking University People's Hospital.During July in 2014,twenty-two emmetropias of 22 normal volunteers aged 21-27 years were recruited from Peking University People's Hospital under the written informed consent.An open-field infrared refractometer was used to monitor and record pupil diameter and accommodative response under three conditions including non-prism,3△ BI prism,and 3△ BO prism.The accommodative response value was calculated as the difference between reading value and-3.0 D,and root mean square (RMS) of accommodative response value served as amplitude of accommodative microfluctuation.Spectrum of accommodative response was analyzed by one dimension discrete Fourier transformation.The differences of accommodative response value,amplitude of accommodative microfluctuation and pupil diameter among three conditions were compared using repeated one-way ANOVA.Results The accommodative response values were (+0.31±0.78),(+0.51±0.75) and (+0.18±0.72) D under the non-prism,3△BI prism and 3△BO prismconditions,respectively,with a significant difference among them (F =28.078,P =0.000),and compared with the non-prism condition,the accommodative lag of 3△BI prism condition was increased and that of 3△BO prism condition was reduced (P =0.000,0.012).No significant difference was found in the amplitude of accommodative microfluctuation among the three conditions (F=0.062,P =0.879).The percentages of low frequency signal power (0-0.5 Hz)/total power (0-2.5 Hz) was 97.5％,98.3％ and 91.4％ under the non-prism,3△BI prism and 3△BO prism condition,respectively.The pupil diameter was (5.37-±0.69) mm under the 3 △ BI prism condition,which was larger than (5.07±0.66) mm under the non-prism condition and (5.01 ±0.69) mm under the 3△ BO prism condition (both at P =0.000).Conclusions Compared with wearing 3△ BI prism,wearing 3△ BO prism lessens the accommodative lag,decreases the pupil diameter and reduces the power of low frequency component in accommodative response.

Objective To evaluate the treatment of malignant submandibular gland tumors with surgery combined with 125I radioactive implantation.Methods Thirty-two patients with malignant submandibular gland tumors were treated with surgery combined with 125I seed implantation from December 2005 to December 2012.All of the 32 patients with primary disease were treated by excision of the submandibular gland and neoplasm.None of the patients received wide excision or neck dissection without the evidence of the neck metastases.The planning targets was based on computerized tomography (CT)images,tumors site,extent and pathologic type.The matched peripheral dose (mPD) was 90-110 Gy.Recurrence-free survival (RFS),overall survival (OS) rates and side effects were retrospectively reviewed.Results Totally 32 patients received 1394 radioactive seeds implantation,radioactive seeds and dose distributed were well in all patients.All patients were followed for 15-126 months (mean of 64 months),with 5 recurrence,5 distant metastases,and 4 patients who died of disease.The 3-and 5-year RFS were 93.1％ and 87.9％,and OS rates were 93.3％ and 84.5％,respectively.No severe complications were observed during follow-up.Conclusions The excision of the neoplasm and the submandibular gland,combined with 125I seed implantation brachytherapy was an effective modality for the treatment of malignant submandibular gland tumors.

Objective To evaluate the efficacy of 125Ⅰ brachytherapy alone for the treatment of recurrent parotid gland carcinoma.Methods Recurrent parotid gland carcinoma patients (n =24) treated by 125Ⅰ brachytherapy alone between 2006 and 2013 at Peking University Hospital of Stomatology were enrolled in this retrospective study.All patients underwent surgery or radiotherapy.The local control rate,survival rate,and side effects were evaluated.Results The median follow-up time was 21 months (range,4-59 months).Among the 24 patients,6 had local failure and 10 died during the follow-up period.The 1-and 3-year overall survival rates,progression-free survival rates,local control rates were 74.8％ and 39.3％,74.8％ and 31.5％,82.0％ and 69.4％,respectively.No grade 3 or over radiation injury was found.Conclusions 125Ⅰ seed brachytherapy alone could provide an ahernative treatment method for inoperable recurrent parotid gland carcinoma patients.

Objective:To investigate clinical features of distant metastases ( DM ) and analyze clinico-pathologic risk factors associated with DM from salivary gland carcinomas after being treated by surgery combined with 125 I internal brachytherapy. Methods: Between October 2001 and March 2010, 197 pa-tients with salivary gland carcinoma were treated by surgery combined with 125 I internal brachytherapy and had follow-up for 2 years or more. Univariate and multivariate analyses were performed to evaluate clini-copathologic risk factors that might influence the risk of distant metastases. Results:DM occurred in 28 of 197 patients (14. 2%). The commonest site of distant metastases overall was the lung 89. 3% (25/28), followed by bones 17. 9% (5/28) and liver (4/28). DM developed after an average interval of (44. 2 ± 45. 8) months from the time of initial diagnosis, and the mean interval was 64 months. The average time to death after the diagnosis of DM was only (9. 7 ± 13. 4) months, and the mean time was 12 months. The 3-year locoregional control rate and survival rate were 90. 8%, and 87. 8% respectively,and the 5-year ones 84. 0% and 81. 0%, respectively. Univariate analyses revealed that the risk of distant metasta-ses was significantly influenced by locoregional tumor failure (F=26. 997,P<0. 01) and histologic dif-ferentiation (F=1. 592,P<0. 01). Multivariate analysis of freedom from distant metastases revealed that locoregional control (F=29. 332,P<0. 01) significantly influenced this end point. Conclusion: Sali-vary gland carcinoma could achieve high local control rate after being treated by surgery combined with 125 I internal brachytherapy, and the average interval from diagnosis to DM was prolonged, DM was signifi-cantly influenced bylocoregional control.

Objective To investigate the effects of low frequency repetitive transcranial magnetic stimulation (rTMS) on motor function and excitability of motor cortex in Parkinson's disease (PD) patients and to study the mechanism of PD from the electrophysiology. Methods Twenty-eight patients with PD received 1 Hz rTMS therapy for 15 d. Thirty normal volunteers were enrolled as controls. Unified Parkinson's Disease Rating Scale (UPDRS) and motor evoked potential (MEP) were adopted as assessment indicators. The excitability of motor cortex was assessed by rest motor threshold (RMT), central motor conduction time (CMCT) and the amplitude of MEP. Results The initial RMTs and CMCTs of PD patients were significantly lower than those of the controls, but MEP amplitudes were not significantly different. After rTMS treatment, motor function of PD patients improved, RMTs increased and CMCTs prolonged. Conclusion In PD patients, motor function disorder and increased motor cortical excitability were observed. Low frequency rTMS may inhibit these changes to some extent.

Objective To investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) / heme oxygenase-1 (HO-1) signaling pathway in reduction of acute kidney injury following orthotopic liver transplantation (OLT) by hydrogen-rich saline in rats.Methods Thirty-two healthy adult male SpragueDawley rats,weighing 220-250 g,were randomly assigned into 4 groups (n =8 each) using a random number table:sham operation group (S group),OLT group,hydrogen-rich saline group (HS group),and all-trans retinoic acid (ATRA) group.Laparotomy was performed,and the related blood vessels were isolated in group S.The model of orthotopic autologous liver transplantation was established in OLT,HS and ATRA groups.Normal saline and hydrogen-rich saline 6 ml/kg were injected through the inferior vena cava at 5 min before the portal vein was clamped in OLT and HS groups,respectively.In group ATRA,Nrf2 inhibitor ATRA 7 mg/kg was injected intraperitoneally once a day for 2 consecutive days,the model of orthotopic autologous liver transplantation was established at 16 h after the last injection of ATRA,and the other treatments were similar to those previously described in group HS.At 6 h of reperfusion,blood samples were collected for determination of serum blood urea nitrogen (BUN),creatinine (Cr),interleukin10 (1L-10) and tumor necrosis factor-alpha (TNF-α) concentrations.After blood sampling,the lungs were removed for determination of malondialdehyde (MDA) content,superoxide dismutase (SOD) activity,expression of HO-1,Bcl-2 and Bax mRNA (by using real-time reverse transcriptase polymerase chain reaction),and HO-1 protein expression in lung tissues (by Western blot) and for microscopic examination.The damage to the renal tubules was scored.Results Compared with group S,the serum BUN,Cr and TNF-α concentrations were significantly increased,the serum IL-10 concentrations were decreased,the MDA content and renal tubular damage score were increased,the SOD activity was decreased,and the expression of HO-1 protein and mRNA,and Bcl-2 and Bax mRNA was up-regulated in group OLT (P＜ 0.05).Compared with group OLT,the serum BUN,Cr and TNF-α concentrations were significantly decreased,the serum IL-10 concentrations were increased,the MDA content and renal tubular damage score were decreased,the SOD activity was increased,the expression of HO-1 protein and mRNA and Bcl-2 mR-NA was up-regulated,and the expression of Bax mRNA was down-regulated in group HS (P＜0.05).Compared with group HS,the serum BUN,Cr and TNF-α concentrations were significantly increased,the serum IL-10 concentrations were decreased,the MDA content and renal tubular damage score were increased,the SOD activity was decreased,the expression of HO-1 protein and mRNA and Bcl-2 mRNA was down-regulated,and the expression of Bax mRNA was up-regulated in group ATRA (P＜0.05).Conclusion The mechanism by which hydrogen-rich saline reduces acute kidney injury following OLT is probably associated with activation of Nrf2/HO-1 signaling pathway in rats.

Objective To study the diagnostic value of magnetic resonance imaging (MRI) and spiral CT in thyroid microcarcinoma (TMC), in order to improve the diagnostic accuracy of TMC. Methods The preoperative imaging manifestations of MRI and spiral CT in 68 TMC patients who were confirmed by surgical pathology were retrospectively analyzed, and the diagnostic accordance rates were compared between the independent and the combined diagnosis. Results The diagnostic accordance rates of MRI and spiral CT in TMC were 73.53%(50/68) and 66.18%(45/68). The diagnostic accordance of combined MRI and spiral CT in TMC was 88.24%(60/68). The diagnostic accordance rate of combined MRI and spiral CT was significantly higher than that of independent examine, and there was statistical difference (P<0.05). The lesion detection rate of MRI was significantly higher than that of spiral CT:95.59% (65/68) vs. 83.82% (57/68), but the calcification lesion detection rate of spiral CT was significantly higher than that of MRI: 85.42% (41/48) vs. 4.17% (2/48), and there were statistical differences (P<0.05 or <0.01). There were no statistical differences in the detection rates of irregular shape lesions, boundary indistinct/coarse lesion, signal/uneven density lesions and cervical lymph node metastasis between MRI and spiral CT (P>0.05). Conclusions Spiral CT is superior to MRI in the micro-calcification detection, and MRI, with a high resolution of soft tissue, can display the lesions of surrounding tissue organs and neck lymph node metastasis better. The combined examine can increase the diagnostic accuracy of TMC.