In this paper, the mobile stereotactic radiosurgical system, a new therapeutant for interstitial radiotherapy, is introduced. Its principle and initial clinical applications are also summarized

Generally,pencil beam kernels for photon beam calculation are obtained through Monte Carlo calculations.In this paper,a pencil beam model is set up with a method of deconvolution from measured broad beam profiles.These profiles are usually available in a radiotherapy planning system.Furthermore,this method is applied to computing dose distributions at different sizes.Comparisons with measurements show that the accuracy of the calculated dose distributions fits well in a1%error interval in high dose gradient regions.

Objective To find a method for calculating the scatter dose of irregular fields. Methods The original Day function was improved to vary with radiation depth, and the improved Day function was used for irregular fields to calculate scatter dose. Results The accuracy was greatly improved by making Day function depend on radiation depth, and the error was within 1.5%. Conclusion This method can be used to calculate the scatter dose of irregular fields as well as rectangular fields.

Since the body is a good conductor,the pacing signals and cardio-signals can be acquired together by ECG measuring circuit. The high pacing signals interfere with the processing of cardio-signal. This paper introduces a new method for restraining pacing signals and compares it with the traditional one based on slew inhibition. The result indicates that the new method is superior to the traditional one.

Objective:To analyze the factors related to metastasis of contralateral central lymph node (CLN) in cN0 papillary thyroid car-cinoma (PTC) and discuss the indications for CLN dissection. Methods:We enrolled 149 unilateral PTC patients who underwent total thyroidectomy and prophylactic bilateral (CLN) dissection. This work analyzed the relationship of gender, age, extrathyroidal extension, multifocality, thyroiditis, ipsilateral central lymph nodes, and prelaryngeal lymph node with CLNs. Results:The rates of metastasis to ip-silateral and contralateral central compartments were 73.2%and 23.5%, respectively. In univariate analysis, gender, age, tumor size, multifocality, and thyroiditis were not important in predicting contralateral central compartment lymph node metastasis (P=0.792, 0.097, 0.531, 0.269, and 1.000, respectively);by contrast, extrathyroidal extension (P=0.017), prelaryngeal lymph nodes (P=0.006), and ipsilateral CLNs (P<0.001) are related to CLN metastasis. However, multivariate analysis showed that ipsilateral central metastasis was an independent risk factor for lymph node metastasis in the contralateral central region when the number of ipsilateral central metas-tases is≥3 (P=0.010). Conclusion:Extracapsular invasion, prelaryngeal lymph nodes, and ipsilateral CLN influence the metastases of CLN. Bilateral CLN dissection should be performed when the number of ipsilateral central metastases is≥3 and there is merger of ex-tra-laryngeal lymph nodes or capsule invasion.

Objective To summarise and analyze the clinical effecacy of endovascular treatment(internal holmium laser incision,bal-loon dilation,ureter dilator,rigid ureter dilation)for ureteral stricture.Methods The clinical data of 628 patients from January 2010 to Jan-uary 2015 in our hospital were analyzed.The relevant operation indicators,postoperative complications and recovery condition were recorded and analyzed.Results The operation time was 5.5 to 29 minutes,with average time of 16.5 minutes,no ureteral avulsion,ureteral fragmen-tation and massive haemorrhage happened.All patients were followed up for 6 to 36 months,591 cases(94.1%)were cured,29 cases (4.6%)of postoperative stricture recurrence received endovascular treatment again,8 patients(1.3%)conversion to open ureterolithotomy. Conclusion Endovascular treatment of ureteral stricture is diversified within holmium laser incision,it has the advantages of shorter opera-tion time,fewer complications,less trauma,repeatability and so on,which is an effective and safe treatment method.

Objective To analyze the factors and prognosis of graft recovery after donation after citizens death (DCD) donor renal transplantation.Methods A retrospective analysis of 67 cases of DCD renal transplantation from August 2012 to September 2015 in our hospital was carried out.According to the stability of renal function after operation,the patients were divided into group A (51cases) with stable renal function,and 16 cases in group B (delayed graft function after operation).The clinical data of two groups including age,gender,cause of death,warm ischemia time,type of dialysis,and application of norepinephrine before operation were collected and analyzed.The related factors of graft function recovery were analyzed.Logistic regression analysis was used to analyze the risk factors of graft functional recovery after operation.The 3-month,6-month,1-year and 18-month survival rate after operation in the two groups was compared.Results The causes of death,the time of ischemia,the type of dialysis before operation,the application of norepinephrine before operation,infants and young donors were related factors of graft function recovery (P ＜ 0.05).Logistic regression analysis showed that cerebral hemorrhage death donor,the long thermal ischemia time,the preoperative hemodialysis and the application of norepinephrine before operation were the risk factors of delayed graft function recovery (P＜0.05).The 3-month,6-month,1-year and 18-month survival rate after operation in group A was higher than that in group B,with the difference being statistically significant (P＜0.05).Conclusion Cerebral hemorrhage death donor,the long thermal ischemia time,the preoperative hemodialysis and the application of norepinephrine before operation were the independent risk factors of delayed graft function recovery.And the prognosis of patients with delayed graft function was poor.Clinical risk should be eliminated or reduced in clinical practice,which can effectively prevent the delayed graft function and further improve the prognosis of the patients.

Objective To investigate the relationship between subgroups of central lymph node metastasis (sCLNM) and lateral lymph node metastasis (LNM) of unilatal papillary thyroid carcinoma (uPTC) with cervical lymph node negative(cN0).Methods The clinical and pathological data of 161 patients with cN0-uPTC who underwent total thyroidectomy+central lymph node dissection+lateral lymph node dissection from Jan.2016 to Dec.2016 were retrospectively analyzed.The relationship between the lymph node metastasis of each subarea in the central area of the affected side and the lymph node metastasis of the affected side was investigated.Results Binary logistic regression analysis of cN0-uPTC subregions in the affected central region showed:pre-laryngeal lymph node metastasis,pre-tracheal lymph node metastasis and paratracheal lymph node metastasis were independent risk factors for lymph node metastasis in the affected lateral region(P=0.008,0.016,0.035,respectively).Prelaryngeal lymph node metastasis was an independent risk factor for lymph node metastasis in the affected area Ⅱ (P=0.015).Pre-tracheal lymph node metastasis was an independent risk factor for lymph node metastasis in affected area Ⅲ (P=0.004).Pre-tracheal and para-tracheal lymph node metastasis were independent risk factors for lymph node metastasis in the affected Ⅳ area (P=0.035,0.011,respectively).Conclusions The lymph node metastasis pathway of thyroid cancer had certain regularity.The pre-laryngeal lymph node metastasis has the prediction value for the lymph node metastasis of the affected area Ⅱ.The pre-tracheal lymph node metastasis has the prediction value for the lymph node metastasis of the affected area Ⅲ.The pre-tracheal and paratracheal lymph node metastasis have the prediction value for lymph node metastasis of the affected area Ⅳ.Lymph node dissection in affected areas Ⅲ and Ⅳ needs to be considered in patients with pre-tracheal or paratracheal lymph node metastases.On this basis,lymph node dissection on the affected areas Ⅱ,Ⅲ,and Ⅳ might be considered if there is pre-laryngeal lymph node metastasis at the same time.

OBJECTIVE To identify the role of mixed lineage kinase domain like protein(MLKL)in cerebral small vessel disease(CSVD)and explore the underlying mechanism.METHODS Transient bilateral common carotid artery occlusion(tBCCAO)was used to establish a mouse model of CSVD.Immunofluorescence staining and Western blotting were used to observe the expres-sions of RIPK3/MLKL signaling molecules in brain tissues at 7,14 and 28 d after tBCCAO.Open field test,rotarod test,Y-maze and novel object recognition test were used to observe the effect of MLKL knockout on cognitive func-tion after tBCCAO.Blood-brain barrier(BBB)disruption was observed by sodium fluorescein permeability test and the expressions of tight junction proteins.Immunoflu-orescence staining and Western blotting were used to detect the expression of microglia marker Iba-1,astro-cyte marker GFAP,and NLRP3/Caspase-1 signaling mol-ecules in the hippocampus of CSVD mice.ELISA was used to detect the level of inflammatory factors(TNF-α,IL-1β,IL-18)in hippocampus.RESULTS The expres-sions of RIPK3/MLKL signaling molecules increased in cortex and hippocampus after tBCCAO,especially on day 14.The expression of pMLKL mainly increased in neurons,glia cells and endothelial cells in CSVD mice.MLKL knockout improved the cognitive functions such as motor learning,spatial learning and working memory,and object recognition ability in CSVD mice.MLKL knock-out alleviated the leakage of sodium fluorescein and attenuated the down-regulation of tight junction proteins at 1 d and 14 d after tBCCAO.At 14 d after tBCCAO,MLKL knock out inhibited the activations of microglia and astrocytes,attenuated the expressions of NLRP3/cas-pase-1 molecules,and decreased the levels of inflamma-tory factors in the hippocampus of mice.CONCLUSION Genetic inhibition of MLKL exerts protective effects against cognitive impairment by ameliorating BBB dam-age and neuroinflammation in a mouse cerebral small vessel disease model.

Objective: Remuzzi scoring system is utilized for assessing the degree of renal tissue damage in donors with hypertensive cerebral hemorrhage and donors with brain trauma after cardiac death. To explore the prognosis of hypertensive cerebral hemorrhage donor kidney in renal transplant recipients. Methods: The kidney donated by DCD between January 1, 2016 to June 1, 2018 were retrospectively reviewed. Pathological biopsy was performed before transplantation and hematoxylin-eosin (HE) staining after sectioning. The degree of renal tissue lesions was evaluated by Remuzzi scoring system. According to the source of donor kidney, they were divided into two groups of donors with heart failure due to hypertensive cerebral hemorrhage (HCH) and those with brain trauma (BT). Both groups of donor kidneys were preserved by low-temperature machine perfusion. The immunosuppressive regimen was identical in both groups. The prognosis of two groups was compared by serum creatinine (Scr) at Month 1/6/12 post-operation and cumulative graft survival rate over a follow-up period of 12-36 months. Results: The renal Remuzzi score of HCH donors was significantly higher than that of BT donors. The maximal creatinine clearance rate was significantly lower than that of BT donors [(86.8±27.8) vs (115.4±23.2) ml/min, P<0.05]. At 1/6/12 months post-transplantation, serum creatinine levels were (76.1±18.5), (72.4±16.2) and (71.4±16.8) μmol/L in BT group and (160.3±33.4), (154.3±32.6) and (146.4±29.1) μmol/L in HCH group. The SCr in BT group at 1/6/12 months was lower than that in HCH group (P<0.05). Kaplan-meier analysis showed no significant inter-group difference in graft survival between two groups over a follow-up period of 12 to 36 months (Log-Rank test, P=0.485). Conclusions No significant difference exists in short-term survival rate of kidneys from HCH and BT donors. The recipients of HCH donor's kidney have higher serum creatinine levels than those of BT donors. Selective use of kidney transplants in patients with cardiac death caused by HCH may greatly reduce the waste of donor kidney and improve the quality-of-life of patients with end-stage renal disease.