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Objective:Topredict the three-dimensional dose distribution of regions of interest (ROI) with brachytherapy for cervical cancer based on U-Net fully convolutional network, and evaluate the accuracy of prediction model.Methods:First, 100 cases of cervical cancer intracavity combined with interstitial implantation were selected as the entire research data set, and divided into the training set ( n=72), validation set ( n=8), and test set ( n=20). Then the U-Net was used to construct two models based on whether the uterine tandem and the implantation needles were included as the distinguishing factors. Finally, dose distribution of 20 cases in the test set were predicted using the trained model, and comparative analysis was performed. The performance of the model was jointly evaluated by , and the mean absolute deviation (MAD). Results:Compared with the model without the uterine tandem and the implantation needles, the of the rectum was increased by (16.83±1.82) cGy ( P<0.05), and the or of the other ROI were not different significantly (all P>0.05). The MAD of the high-risk clinical target volume, rectum, sigmoid, small bowel, and bladder was increased by (11.96±3.78) cGy, (11.43±0.54) cGy, (24.08±1.65) cGy, (17.04±7.17) cGy and (9.52±4.35) cGy, respectively (all P<0.05). The MAD of the intermediate-risk clinical target volume was decreased by (120.85±29.78) cGy ( P<0.05). The mean value of MAD for all ROI was decreased by (7.8±53) cGy ( P<0.05), which was closer to the actual plan. Conclusions:U-Net fully convolutional network can be used to predict three-dimensional dose distribution of patients with cervical cancer undergoing brachytherapy. Combining the uterine tube with the implantation needles as the input parameters yields more accurate predictions than a single use of the ROI structure as the input.
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Objective To compare the dosimetric differences between free-hand method and virtually optimized method for implanting needles in intracavitary and interstitial combined brachytherapy (IC/IS BT) of cervical cancer,and to explore the improvement space of the existing interstitial brahcytherapy plan.Methods High-dose-rate cervical cancer IC/IS BT plans (short for Treatment-Plan) of 18 cases were retrospectively analyzed.For each treatment plan,Nucletron Oncentra 3D brachytherapy planning system was utilized to redesign the virtually optimized insertion method IC/IS BT plan (short for Optimized-Plan).Dose volume histogram was adopted to evaluate the dose distribution in high-risk clinical target areas and exposure dose to organ at risk (OAR).The plan execution efficiency between two plans was also assessed.Results Comparing these two plans,the differences in conformity and uniformity of dose distribution of the target area were statistically significant (P=0.000,0.008).The differences of D0.01 cm3,D1 cm3,D2 cm3 and D5 cm3 in bladder,rectum,sigmoid and small bowel were all statistically significant (all P＜0.05).Optimized-Plan could reduce the D2 cm3 of bladder,rectum,sigmoid and small bowel by 60.41,36.43,27.53 and 12.43 cGy,respectively.The execution time for the Treatment-Plan and Optimized-Plan were (857.92±243.39) s and (804.53±239.13) s with statistical significance (P＜0.001).Conclusions Compared with the free-hand method,virtually optimized method yields more conformable coverage of the target area and more uniform dose distribution.At the same time,the doses of each OAR are reduced to different degrees and the execution time of the plan is also shortened.
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Objective To analyze the epidemiological characteristics of patients with sea lice injury in coastal baths in Qinhuangdao City, and provide scientific evidence for the importance of prevention of sea lice injury and the early warning of sea lice outbreak. Methods The data of 2 659 patients with sea lice injury, including gender, age composition, severity of bruises and other epidemiological data reported by the coastal bathing stations in Qinhuangdao City from 2016 to 2018 (mainly from July to August) were retrospectively analyzed, and the correlation between the temperature at the surface of sea water and the number of patients with sea lice injury was also analyzed. Results Among the 7 bathing beaches along the coast of Qinhuangdao City, Dongshan Bathing Spot (1 101 cases) and Repulse Bay Bathing Beach (1 365 cases) had the largest numbers of bruises, while the Gold Coast Bath had the least (only 5 cases), and the differences in number of bruises in different baths were statistically significant in 2016, 2017, 2018 years (277, 1 890, 492 cases respectively, χ2= 490.611, P < 0.05). Among 2 659 patients, 1 124 were children (≤14 years old), 1 535 were adult, 1 570 male and 1 089 female patients. The severity type of patients' sea lice injury in each bath was mainly mild to moderate type; among the total injury cases, there were 2 589 cases with mild type injury accounting for 97.37%, 61 cases with moderate type (2.29%) and 9 cases with severe type (0.34%). A linear trend between sea surface temperature and the patients' number of bruises was seen, and there was a positive correlation between the sea surface temperature and the patients' number (r = 0.433, P < 0.05). Conclusion The sea lice injuries in Qinhuangdao City are mainly distributed in the Dongshan and Repulse Bay Baths, the main type of injury is light one, and in the mean time the injury is influenced by factors such as popularization of science, medical care, environmental factors, and collective sea lice drift, etc.
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Objective To compare the relative dose of small fields measured by clinically common detectors and those obtained from Monte Carlo simulation in order to obtain the accurate measurement method, and to modify the inappropriate detectors.Methods The percentage depth-dose distribution curve and profile (flatness and symmetry) curves were collected at 2 cm×2 cm, 3 cm×3 cm, and 4 cm×4 cm under 6-MV X-ray of Trilogy linear accelerator by CC13, PFD, SFD, and blue phantom.The results were compared with the stimulation results from Monte Carlo method (the current gold standard).The correction factors for the detectors with large error were calculated to provide reference data for clinical practice.Results The results measured by SFD detector were most close to the results from Monte Carlo simulation.The measurement errors of CC13 and PFD detectors were large.The correction factor in the penumbra for CC13 and PFD detector was 0.664-1.499.Conclusions SFD detector is better than CC13 and PFD detector in the measurement of small fields, but CC13 and PFD detector can provide reference data for clinical practice after the corresponding correction.
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Objective To study the significance of treating advanced primary hepatic carcinoma by using the different methods combined with chemotherapy. Methods One hundred and fifteen cases with advanced primary hepatic carcinoma were divided into 5 groups by accepting different chemotherapy: the groups of interventional-chemotherapy (group A, 40 cases), whole body hyperthermia combined with chemotherapy (group B, 16 cases), only chemotherapy (group C, 9 cases), local heat chemotherapy (group D, 26 cases), symptomatic supportive (group E, 24 cases) for comparing response rate (RR) and survival time between each other. Results The RR in group A,B,C were 30.5 % (12/40), 12.5 % (2/16), 11.1 % (1/9) respectively, and there was no significant difference among three groups (P>0.05). The mid-survival time of five groups were 7.7, 9.2, 7.9, 6.0, 4.7 months, and there was significant difference between group B and group E (P<0.05). The 0.5-, 1-, 2-year survival rate in group B were higher than those in group E with significant difference (81.2%vs. 29.1%, 37.5%vs. 12.5%, 12.5%vs. 0, all P<0.05). Conclusions The RR of only routine chemotherapy is low, while the RR of interventional-chemotherapy and local heat chemotherapy is high with non-prolonged survival time. Whole body hyperthermia combined with chemotherapy have active effects in helping to improve the efficacy and prolong the survival time in retreatment patients with advanced hepatic tumor.
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Objective To establish the high performance liquid chromatography(HPLC) fingerprint of wuzi yanzong pills. Methods HPLC was performed on Agilent Extend C18 column (250 mmí4. 6 mm,5 μm) with a gradient elution system using acetonitrile:methanol (101)-0. 4% phosphoric acid as the mobile phase. The column temperature was set at 30 ℃ and the flow rate was 1. 0 mL·min-1 . The eluate was detected at the wavelength of 254 nm. Chromatographic peaks were identified by LC-MS method. Results Nine common peaks in wuzi yanzong pill samples were identified by comparing their LC-MS data with those of reference compounds and related reference reports. The HPLC fingerprint of wuzi yanzong pills was finally developed based on the analysis of sixteen batches of samples and their similarities were above 0. 93. Conclusion This method has high precision,stability and repeatability. This study could be used for overall quality assessment of wuzi yanzong pills.
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Objective To investigate the possibility of anti-liver fibrosis of 13-estradiol nanoparticle prepared by interfacial polymeri-zation method with butylcyanoacylate as carrier material (E2-PBCA-NP) and its effect on the expression of transforming growth factor β1 and connective tissue growth factor in pig serum induced animal fibrotic model. Methods Male Sprague-Dawley (SD) rats were random divided into five groups. Except normal control group, other four groups were all given intraperitoneal injection with pig serum. Therapeutic drugs were administered to rats from the ninth week after injection of pig serum. All rats were killed at the end of the twelfth week. Several experi-ments were done as below, the tissues of liver were observed by Masson staining, and the mRNA of TGF-β1 and CTGF of liver samples were detected by RT-PCR. Meanwhile, the expression of TGF-β1 and CTGF protein were detected by immunohistochemistry. Results It showed that both E2 and E2-PBCA-NP treatment groups had lower stage of liver fibrosis, according to the observation of pathology by Masson staining (P < 0.05). The anti-liver fibrosis effect of E2-PBCA-NP treatment group was better than that of E2 treatment group (P < 0.05). The mRNA and protein level of TGF-β1 and CTGF were markedly reduced by E2 and E2-PBCA-NP treatment, compared with liver fibrotic model groups (P <0.01). There was no statistical difference between E2-PBCA-NP and E2 treatment (P >0. 05), while no significant change was observed in blank nano -particle group (P > 0.05). Conclusion Both E2-PBCA-NP and E2 had anti-liver fibrosis activity. E2-PB-CA-NP has stronger anti - liver fibrosis activity than E2, which could be resulted from the inhibition of TGF-β1 and CTGF expression.
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Objective To study the human telomerase reverse transcriptase (hTERT) and spleen tyrosine kinase (SYK) activity expression and molecular margin in the tumor center and peripheral tissues of patients with colorectal cancer, and to explore the security of tumor surgical margins. Methods The expressions of hTERT and SYK were examined by SABC and Supervisan immunohistochemistry in 20 specimens of colorectal cancer and tissues 1 cm, 2 cm, 3 cm, 4 cm and 5 cm, away from proximal and distal margin of the tumor respectively. Results The positive expression rate of hTERT in colorectal cancer was 80.00 %, the rate in tissues 3 cm, 4 cm and 5 cm away from the tumor margin was 0. The positive expression rate of hTERT in tissues from the cancer center to 3 cm away from the tumor margin was gradually diminishing (P<0.01). The positive expression rate of SYK in colorectal cancer was 10.00 %, the positive expression rate of SYK in tissues from the cancer center to 3 cm away from the tumor margin was gradually increased (P<0.05). Conclusion There is molecular margin around colorectal cancer tissues. Considering hTERT and SYK expressions, 3 cm can be defined as the safe molecular margin for the radical operation of colorectal cancer.