Objective:To study the differences in the cumulative dose between deformable image registration (DIR) and simple dose-volume histogram (DVH) summation in the fractionated brachytherapy of cervical cancer, and to analyze the feasibility of the application of DIR in the dosimetry assessment of targets and organs-at-risk (OARs) in the brachytherapy.Methods:A retrospective analysis was conducted for 13 cases with primary cervical cancer treated with four fractions of interstitial brachytherapy guided by CT images. The four CT images of each cases were registered using an intensity-based DIR. Then, the cumulative doses (the D2 cm 3, D1 cm 3, and D0.1 cm 3 of the bladder, rectum, intestine, and colon and the D90for targets) after DIR were calculated and compared to those obtained using simple DVH summation. Afterward, the correlation between the dose difference and dice similarity coefficient (DSC) was analyzed. With the dose difference (the remaining dose of OARs caused by the DIR) as limits, a new plan was made for the latest CT to calculate the dose increase to targets. Results:Compared to simple DVH summation, DIR allowed the cumulative doses of the D2 cm 3 and D1 cm 3 of bladder to be decreased by (2.47±1.92) and (2.82±2.73) Gy, respectively on average ( t=-3.65, -2.93, P < 0.05), those of the D2 cm 3, D1 cm 3, and D0.1 cm 3 of rectum to be decreased by (2.05 ± 1.61) Gy, (1.51 ± 1.58), and (3.21 ± 2.50) Gy, respectively on average ( t=-4.02, -3.02, -4.06, P < 0.05), and those of the D2 cm 3, D1 cm 3, and D0.1 cm 3 to be decreased by (1.42 ± 0.99), (1.55 ± 1.28) Gy, and (2.43 ± 1.95) Gy, respectively on average ( t=-3.52, -2.96, -3.06, P < 0.05). There was no significant statistical difference in the D90 of targets, the D0.1 cm 3 of the bladder, and the D2 cm 3, D1 cm 3, D0.1 cm 3 of the colon ( P > 0.05) between both methods, and there was no distinct correlation between DSC and dose difference ( P > 0.05). The DIR increased the dose to targets, with a median value of 150 cGy. However, the accuracy of the DIR should be improved. Conclusions:In clinical practice of multiple fractions of brachytherapy for cervical cancer, it′s still recommended to adopt the simple dose summation method to assess the doses to targets and OARs.

Objective:To investigate the diagnosis and treatment of hepatic artery thrombosis (HAT) after adult orthotopic liver transplantation.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 411 patients who underwent adult orthotopic liver transplantation in the First Affiliated Hospital of Xi ′an Jiaotong University from December 2011 to July 2018 were collected. There were 328 males and 83 females, aged from 21 to 66 years, with a median age of 46 years. Observation indicators: (1) incidence of HAT and its clinical characteristics; (2) diagnosis of HAT; (3) treatment of HAT; (4) follow-up. Follow-up using outpatient service, telephone interview or WeChat group communication was conducted to detect the incidence of biliary stricture and survival of patients up to August 2018. Measurement data with normal distribution were represented as Mean± SD, measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers or percentages. Survival rate was estimated using the Kaplan-Meier method. Results:(1) Incidence of HAT and its clinical characteristics: 11 of 411 patients had HAT after orthotopic liver transplantation with the incidence of 2.68%(11/411), including 10 males and 1 female, aged 44 years(range, 22-63 years). The time to occurrence of postoperative HAT was 4 days(range, 1-15 days). The etiologies of 11 patients included 6 cases of hepatitis B virus-related cirrhosis, 1 case of hapatitis related cirrhosis, 1 case of hepato-cellular carcinoma, 1 case of liver cirrhosis, 1 case of alcoholic hepatitis related cirrhosis, 1 case of wilson disease. All the 11 patients were ABO compatible. The cold ischemic time and warm ischemic time of donor liver were (316±89)minutes and (13±4)minutes, respectively. Type Ⅰ arterial anasto-mosis was conducted in 11 patients. The clinical manifestations included asymptomatic type in 10 patients and sepsis type in 1 patient. (2) Diagnosis of HAT: all the 11 patients were confirmed with HAT by endovascular angiography, including 7 cases showed no arterial flow under Color Doppler ultrasound, and contrast-enhanced ultrasound indicated HAT. Two patients showed increased hepatic artery resistance index under Color Doppler ultrasound, and contrast-enhanced ultrasound indicated 1 case of HAT and 1 case of anastomotic stenosis. One patient showed slow velocity of hepatic artery blood flow and low resistance index under color Doppler ultrasound, and contrast-enhanced ultrasound indicated HAT. One patient showed slight blood flow signals under Color Doppler ultrasound, and contrast-enhanced ultrasound indicated HAT. (3) Treatment of HAT: 11 patients received endovascular therapy. Six patients had HAT completely disappeared after thrombolytic therapy, 5 patients with residual thrombosis continued thrombolytic therapy with microcatheter urokinase. Six patients with complications were improved after symptomatic treatment. HAT completely disappeared after (6.7±2.6)days of treatment and the clinical success rate was 11/11. (4) Follow-up: 11 patients were followed up for 19-1 722 days, with a median follow-up time of 46 days. During the follow-up, 4 patients had biliary stricture and underwent stent implantation. Nine patients survived with 1-, 3-, 5-year overall survival rates of 75%, 75%, 75%, and 2 patients died.Conclusions:The incidence of HAT after adult orthotopic liver transplantation is low and clinical manifestations are atypical. Contrast enhanced ultrasound can improve diagnosis of suspected thrombosis. Endovascular therapy is safe and effective, which can significantly improve the blood flow of hepatic artery.

Objective:To establish a dosimetric method based on the well-chamber to verify the accuracy of the source positioning and dwelling time for the afterloading machine, aiming to provide a new method for the quality control of afterloading machine.Methods:The principle of this method was explained according to the hardware structure of the well-chamber. Then, the precision of this method was analyzed by the simulation test and data fitting. The feasibility test was also performed. And the advantages and disadvantages of this method were compared with those of the traditional method.Results:The precision of this method for detecting the source positioning was 0.07 mm and the dwelling time was 0.09 s, respectively. In the feasibility test, the standard deviation of the measure value was below 3%.Conclusions:The well-chamber method has high precision and convenient operation. It can be applied in the rapid verification of the relative accuracy of the source positioning and dwelling time of well-chamber.

Surgical treatment for bone and soft tumors of pelvis and sacrum presents a big challenge, because of the complex anatomy of sacropelvic region, large tumor volume at presentation, rich blood supply to the tumor and visceral involvemen, et al. Therefore, surgical excision and reconstruction are technically difficult for sacropelvic tumors. Extensive intraoperative haemorrhage could be life-threatening, and this issue remains a major concern. How to effectively control bleeding during surgery is critical for successful operation and patient's favorable prognosis. Some previous attempts, such as interventional selective internal iliac artery embolization or manual ligation through an additional anterior approach, were tested to be ineffective. Inspired by the success of resuscitative endovascular balloon occlusion of the aorta (REBOA) which resemble an endovascular tourniquet for traumatic hemorrhagic shock, some researchers have applied this techinique to control surgical bleeding during pelvic or sacral tumor resection.The authors have performed REBOA for more than 1 500 sacropelvic tumr surgeries since 2003 in Peking University People's Hospital. The patient age, the diameter of femoral artery and aorta, atherosclerosis, as well as tumor location, volume and expansion and blood suppy, have to be thoroughly evaluated prior to REBOA administration. Admittedly, the application of REBOA do reduce intraoperative bleeding, shorten the operation duration, improve the safety of surgery, yet some complications were observed including local hematoma at the puncture site, acute arterial thrombosis, femoral artery pseudoaneurysm or occlusio, et al. The purpose of this study is to review the literature on REBOA administration in pelvic and sacral tumors excision, with the focus on its indications, performing procedure, the safety and efficacy, and complications. Moreover, in order to popularize the clinical application of aortic balloon occlusion in the future, we summarize our experience of abdominal aortic balloon occlusion over 10 years.

Objective:To establish a nursing intervention process for Intensive Care Unit (ICU) patients with thirst after cardiac surgery to guide clinical practice, so as to provide a basis for the scientific management of thirst in patients after cardiac surgery.Methods:We searched domestic and foreign databases to obtain and evaluate relevant literature on thirst in critically ill patients. After discussion by the research group, the first draft of the thirst intervention process was formulated. The Delphi method was used to conduct two rounds of expert consultation, and finally the nursing intervention process for ICU patients with thirst after cardiac surgery was determined.Results:Through two rounds of expert consultation, 4 first-level indicators (pre-intervention evaluation, graded intervention, post-intervention evaluation, health education) , 11 second-level indicators, and 29 third-level indicators were formed. The authority coefficients of the two rounds of expert consultation were 0.83 and 0.85 respectively, and Kendall's W were 0.259 and 0.214 respectively. Conclusions:Expert advice tends to be consistent, highly authoritative, and good coordination, which can provide a scientific management basis for the construction of nursing intervention process for ICU patients with thirst after cardiac surgery.

Objective: To study the feasibility of using the PTW729 2D array ion-chamber to verify the relative dose distribution calculated with the Acuros BV algorithm. Both advantages and disadvantages of the method were analyzed to provide reference for practical clinical practices. Methods: Based on self-built measurement phantoms, the dose distribution on the same slice of the phantom was measured with PTW729 and film, respectively, under the same measurement condition and plan. The dose distributions obtained by the two method were compared with the result calculated with Acuros BV, separately, by using γ analytical tool. And the stability of the PTW729 was tested. Results: The γ comparison value was 95.9% between the film and Acuros BV, 98.9% between the PTW729 and Acuros BV and 88.0% between the film and PTW729, with 95.0%, 100.0%, and 100.0%, in their stability test respectively. Conclusions PTW729 2D array ion-chamber can be applied to the rapid verification of Acuros BV algorithm-calculated relative dose distribution.

Objective: This paper summarized the research status and progress of photodynamic therapy (PDT) and sonodynam-ic therapy (SDT), and we hope this can be a useful reference for clinics or research. Methods: In this review we expound their molecular mechanisms in detail and classify the photosensitizer and sonosensitizer, indicate their applications for the cancer treatment and summarize their new treating modes. PDT and SDT have huge potential for cancer treatment. Results: PDT and SDT have achieved a certain results, whereas there are still many problems, such as tissue oxygen content, new photosensitizer and sonosensitizer, drug dosage and mechanisms of SDT. Conclusions: PDT and SDT, which are new methods for treating cancer, have shown a good application prospect. But PDT has not been universal in clinics and SDT is still in the experiment stage.

In th is paper, an Extremely Low Frequency Multi-waveform Electromagnetic Field Generator has been developed with single chip computer, which provides pulsed, rectangular, triangular and sinusoidal magnetic field with the frequency range from 0-150 Hz and the intensity range from 0-50 mT. The application shows that the device is easy to operate and the parameters of magnetic fields are stable. It has provided successful application in the experiments on biological effects of magnetics and has obtained valuable result.
Cell Differentiation ; radiation effects ; Cell Proliferation ; radiation effects ; Cells, Cultured ; Electromagnetic Fields ; Equipment Design ; Humans ; Magnetics ; instrumentation ; Osteoblasts ; radiation effects

In order to meet the needs of training high-quality medical persons, combining teaching reform theory with foundational courses teaching practice, we summarize some successful experience in many respects such as construction and reformation of foundational educational system, grasping subject construction goal, bringing up and cultivating scientific researchers, improving experimental conditions. All we have done reveal that the combination of medicine and engineering is the characteristic form of development.

The performance of extremely low-frequency electromagnetic fields (ELEF) can change the response of osteoblasts. In this study a kind of ELEF stimulator, which can radiate sinusoidal, rectangular, triangular and pulsed burst ELEF with frequency of 0-300 Hz and strength of 0-40 mT was developed. The neonatal rat calvarial osteoblasts were treated with the device. The effects of various ELEF stimulation on the osteoblast were evaluated by its proliferation and differentiation. The results demonstrated that rectangular and pulsed burst radiation (15Hz, 5mT) can positively change the proliferation of the osteoblast and inhibit its differentiation, but the sinusoidal one can significantly enhance its differentiation and decrease its proliferation.
Animals ; Animals, Newborn ; Cell Differentiation ; radiation effects ; Cell Proliferation ; radiation effects ; Cells, Cultured ; Electromagnetic Fields ; Osteoblasts ; cytology ; radiation effects ; Rats ; Rats, Sprague-Dawley ; Skull ; cytology