Design and analysis of radio frequency window for the China Fusion Engineering Test Reactor ion cyclotron range of frequency heating system.

The Ion Cyclotron Range of Frequency (ICRF) heating system of the China Fusion Engineering Test Reactor (CFETR) is intended to provide plasma heating with a minimum power output of 20 MW, which demands the Radio Frequency (RF) window to possess a higher performance requirement. This paper presents the design of an RF window for the CFETR ICRF heating system and focuses primarily on the design and confirmation of its electromagnetic performance. The RF window can be effectively matched in the operating frequency range and has an S11 of under -59 dB. The geometry of the cone type ceramics was optimized to reduce the surface tangential electric field distribution. An analysis of the electric field distribution of the RF window at 50 kV indicates that the pressure side was below 2.3 kV/mm and the vacuum side was below 1.3 kV/mm. Furthermore, a transmission line test bench with an open-terminated setup was constructed to conduct withstand voltage tests on the mockup, and the results showed that the mockup could withstand 62 kV for 2 s and 47 kV for 120 s.

Analysis of Mitochondrial Transfer RNA Mutations in Breast Cancer.

Damage of mitochondrial functions caused by mitochondrial DNA (mtDNA) pathogenic mutations had long been proposed to be involved in breast carcinogenesis. However, the detailed pathological mechanism remained deeply undetermined. In this case-control study, we screened the frequencies of mitochondrial tRNA (mt-tRNA) mutations in 80 breast cancer tissues and matched normal adjacent tissues. PCR and Sanger sequence revealed five possible pathogenic mutations: tRNAVal G1606A, tRNAIle A4300G, tRNASer(UCN) T7505C, tRNAGlu A14693G and tRNAThr G15927A. We noticed that these mutations resided at extremely conserved positions of tRNAs and would affect tRNAs transcription or modifications. Furthermore, functional analysis suggested that patients with these mt-tRNA mutations exhibited much lower levels of mtDNA copy number and ATP, as compared with controls (p<0.05). Therefore, it can be speculated that these mutations may impair mitochondrial protein synthesis and oxidative phosphorylation (OXPHOS) complexes, which caused mitochondrial dysfunctions that were involved in the breast carcinogenesis. Taken together, our data indicated that mutations in mt-tRNA were the important contributors to breast cancer, and mutational analyses of mt-tRNA genes were critical for prevention of breast cancer.

[Current status and hotspot of minimally invasive surgery for pancreatic head carcinoma].

With the improvement of laparoscopic equipment and surgical technology,pancreatic surgery has entered the "minimally invasive era".However,the use of minimally invasive pancreaticoduodenectomy in patients with pancreatic head cancer remains controversial.In recent years,China's pancreatic surgeons have been at the forefront of the world in terms of surgical technology,however,surgical philosophy, selection of indication,and perioperative management should be further stregthened. Additionally, the development of medical standards in various regions of China is seriously uneven,and minimally invasive pancreaticoduodenectomy still needs to be further standardized and popularized.Through this article,the author discusses the development status of minimally invasive surgery for pancreatic head cancer and related hot topics with fellow surgeons,in order to further improve the standard diagnosis and treatment of pancreatic cancer in China.

[Recommendations on the diagnosis and treatment of osteoarthritis in China].

Osteoarthritis (OA) is the most common form of arthritis and the leading cause of old age disability, affecting an estimated 302 million people worldwide. OA is seriously overlooked in the world. The awareness of OA and the popularization of standardized diagnosis and treatment are all lacking. Knees, hips, and hands are the most commonly affected joints in OA. Based on the experience of diagnosis and treatment, consensus and guidelines, we formulated this diagnosis and treatment standard in order to standardize the diagnosis and treatment of OA. We hope that our standard can reduce misdiagnosis and mistreatment and improve the prognosis of OA.

[The concept of traditional chinese medicine:history, theory and empirical research].

The concept of traditional Chinese medicine has different connotations and extensions in different historical periods. This paper examines the formation and development of the concept of traditional Chinese medicine in the perspective of history, theory and empirical research, and explores the internal connection among different medical systems and between medicine and other disciplines. It attempts to re-define the connotation and extension of the concept of traditional Chinese medicine in the context of the new era, provide references for building the medical community of the Chinese nation and promote the standardization of Chinese medicine terminology, advance the cross-disciplinary construction and establishing a new medical system with the characteristics of openness and tolerance, in order to provide the solution, wisdom and power of traditional Chinese medicine for global health in the process of building a community of human health.

[Rethinking of surgical indications for pancreatic cystic tumors].

With the progress of imaging technology and the popularization of healthy examination, the detection rate of pancreatic cystic neoplasm(PCN) has increased significantly. PCN has complex disease spectrum, strong heterogeneity, and diverse surgical treatment strategies. Surgical timing and methods directly affect patients' prognosis. Therefore, how to identify malignant tumors and formulate reasonable treatment strategies are the keys to treat PCN. Many guidelines for clinical diagnosis and treatment of PCN have been released, but there are still many disputes about its surgical indications. Hence, fully assessing the surgical indications is of great significance to improve the PCN patients' prognosis. This paper deeply discusses on the surgical indications of PCN by reviewing the current clinical diagnosis, treatment and research progress of PCN, in order to standardize the diagnosis and treatment of PCN.

Impedance matching system using triple liquid stub tuners for high-power ion cyclotron resonance heating in EAST tokamak.

Ion cyclotron resonance heating (ICRH), one of the main auxiliary methods, for high-power and long-pulse plasma heating had been developed in Experimental Advanced Superconducting Tokamak (EAST). An impedance matching system, one important part of ICRH, had been developed for high-power injection and transmitter protection by reducing the reflected power from the antenna. The input impedance in the outlet of the stub tuner can be measured by voltage-current probes installed on the coaxial transmission line between the antenna and triple liquid stub tuners, and the optimum liquid levels in the stub tuners can be calculated based on the input impedance. The calculation and adjustment process of the optimum liquid levels are described comprehensively in this article. Finally, impedance matching had been achieved between two shots during EAST experiments. In the near future, a real-time impedance matching system will be developed to prevent large variations of the ICRH antenna impedance and achieve steady-state and long-pulse operation with the ICRH system.

[Safety and efficacy of percutaneous mechanical thrombectomy through ipsilateral calf venous access in the treatment of entire-limb acute deep venous thrombosis].

Objective: To evaluate the safety and clinical efficacy of percutaneous mechanical thrombectomy (PMT) through ipsilateral calf venous access in the treatment of entire-limb acute deep vein thrombosis (DVT). Methods: From July 2017 to August 2020, the clinical data of patients with entire-limb acute DVT at Renji Hospital, School of Medicine, Shanghai Jiaotong University treated by AngioJet through ipsilateral calf venous access were analyzed retrospectively. All patients received rivaroxaban or warfarin anticoagulant therapy for at least 6 months after operation. Pressure gradient socks were given routinely after operation. All patients were followed up at 3, 6, 12 months and every year after operation. The primary end points were the 12-month primary patency rate and the incidence of post thrombotic syndrome (PTS). The secondary end points included the thrombus clearance rate, total complication rate, bleeding complication rate and the 12-month incidence of moderate to severe PTS. Results: A total of 31 patients were included in the study. The age ranged from 31 to 80 (63±14) years, including 16 males and 15 females, 23 left lower limb DVT and 8 right lower limb DVT. There were 15 cases treated through peroneal venous access, 6 cases through anterior tibial venous access and 10 cases through posterior tibial venous access. Moreover, 9 cases underwent combined catheter-directed thrombolysis, 25 cases underwent iliac vein percutaneous transluminal angioplasty (PTA), and 10 cases underwent iliac vein stenting. The thrombus clearance rate was grade Ⅱ in 19 cases (61.3%) and grade Ⅲ in 12 cases (38.7%). One patient (3.2%) with anterior tibial venous access developed hematoma at the puncture site, which was improved after pressure bandage, and there were no other bleeding and serious complications. All the 31 patients were followed up for at least 12 months, with an average follow-up period of (22±9) months. The 12-month primary patency rate was 77.4% (24/31). The 12-month incidence of PTS was 16.1% (5/31) and the incidence of moderate to severe PTS was 3.2% (1/31). Conclusions: PMT through ipsilateral calf venous access is safe and effective in the treatment of entire-limb acute DVT. Thrombus in the distal popliteal vein can be one-stage removed and the incidence of PTS is low. It is considered as the first choice of access for the endovascular treatment of entire-limb acute DVT.

[Epidemiological analysis of non-enterovirus 71 and non-coxsackievirus A16 enterovirus].

Enteroviruses (EV) are the most common pathogens in humans, often causing large-scale infectious diseases, such as: hand, foot and mouth disease, herpes angina, myocarditis, encephalitis, aseptic meningitis, acute flaccidity Paralysis and acute flaccid myelitis and other nervous system and cardiopulmonary diseases, and them often infect children under 5 years old, severely can cause fatal complications. In recent years, the prevalence of non-enteric virus A71 (EV71) and non-coxsackievirus A16 (CV-A16) enteroviruses has gradually increased, and the dominant strains of EVs have gradually changed. A timely grasp of the etiology, epidemiology, and molecular evolution characteristics of EVs is of great significance to the prevention and control of EVs. Therefore, this article reviews the current status of diseases caused by non-EV71 and non-CV-A16 enteroviruses and analysis the molecular epidemiology, in order to have a certain prompting effect on the prevention and control of EVs.

[Trend analysis on morbidity and mortality of pancreatic cancer in China, 2005-2015].

Objective: To analyze the trend of morbidity and mortality of pancreatic cancer in China from 2005 to 2015 and estimate the related age, period and cohort effect, respectively. Methods: Joinpoint regression analysis was used to analyze the trend of morbidity rate and mortality rate of pancreatic cancer during 2005-2015 and calculate the annual percentage change and average annual percentage change based on the data in the annual report of China Cancer Registry. Population aged 20-84 years was fitted by the Age-Period-Cohort model to estimate the effect parameters of age, period and cohort. Results: The trend variations of the crude morbidity rate and crude mortality rate of pancreatic cancer were consistent. The morbidity rate of pancreatic cancer firstly increased before 2008 and then decreased. The morbidity rate and mortality rate of pancreatic cancer were higher in men than women, and higher in urban areas than in rural areas. From 2005 to 2015, the overall age-standardized morbidity rate of pancreatic cancer increased by 2.78% annually and the overall age standardized mortality rate of pancreatic cancer increased by 2.24% annually. The age standardized morbidity of pancreatic cancer in rural men changed more rapidly, with an average annual increase of 3.74%, and the age standardized mortality rate of pancreatic cancer in urban men changed more rapidly, with an average annual increase of 3.57%. The age effect on the morbidity and mortality of pancreatic cancer increased with age, and the effect was most obvious in age group 70-80 years, the period effect increased over time and the cohort effect decreased with year, but rebound or fluctuation was observed after 1976. Conclusions: The morbidity rate and mortality rate of pancreatic cancer in China increased slightly in past decades. Strategies on effective prevention and control of pancreatic cancer should be developed in the future.

[The Chinese guidelines for the diagnosis and treatment of pancreatic neuroendocrine neoplasms (2020)].

Pancreatic neuroendocrine neoplasms (pNENs) are highly heterogeneous, and the management of pNENs patients can be intractable. To address this challenge, an expert committee was established on behalf of the Group of Pancreatic Surgery, Chinese Society of Surgery, Chinese Medical Association, which consisted of surgical oncologists, gastroenterologists, medical oncologists, endocrinologists, radiologists, pathologists, and nuclear medicine specialists. By reviewing the important issues regarding the diagnosis and treatment of pNENs, the committee concluded evidence-based statements and recommendations in this article, in order to further improve the management of pNENs patients in China.

[Ultrasound-guided percutaneous transluminal angioplasty in the treatment of arteriovenous fistula immaturation: day surgery mode and clinical efficacy].

Objective: To summarize the clinical effect of ultrasound-guided percutaneous transluminal angioplasty (PTA) in the treatment of arteriovenous fistula (AVF) immaturation under day surgery mode. Methods: The clinical data was retrospective analyzed of patients with AVF immaturation who were treated by ultrasound-guided PTA under day surgery mode from November 2016 to June 2019 in Renji Hospital. The basic information, lesion location, puncture approach, number and diameter of balloon used were counted. The primary and secondary patency rates were calculated at 6 and 12 months after operation. Results: In all of the 21 patients, 11 patients were male and 10 patients were female. The mean age was (52.6±12.9) years old. There were 20 of the 21 patients who were treated successfully. One patient had AVF reconstruction with vascular rupture, and the complication rate was 4.8% (1/21). The length of hospitalization was (1.05±0.71) days, and the cost was (11 487.7±4 401.4) yuan. The follow-up time was (19.7±8.3) months. The 6-month and 12-month primary patency rate were 70% and 55%, and the 6-month and 12-month secondary patency rate were both 90%. Conclusion: Ultrasound-guided PTA in the treatment of AVF immaturation under day surgery mode is safe and effective, which has a high technical success rate and good patency rate for AVF maturation.

Quantitative analysis of gastrointestinal bleeding with technetium-99m-labeled red blood cells in an experimental model.

OBJECTIVE: The aim of this study was to propose a quantitative analysis method using technetium (Tc)-99m-labeled red blood cell RBC imaging to allow calculation of the amount and the rate of gastrointestinal (GI) bleeding. MATERIALS AND METHODS: Rabbit models of fixed-GI and continuous-GI bleeding were created using catheter infusion. The amount and rate of bleeding were calculated and compared with the infused amount and rate. RESULTS: No significant differences in calculated or actual amounts or rates of GI bleeding were observed after 2, 4, and 6 hours of catheter infusion of Tc-99m-RBCs. CONCLUSIONS: The proposed quantitative analysis method using Tc-99m-RBCs GI scintigraphy can accurately calculate the actual amount and rate of GI bleeding.

[Effect of polyphyllin â ¡ on the proliferation, invasion and chemosensitivity to temozolomide of glioma cells].

Objective: To investigate the effect and mechanism of Polyphyllin Ⅱ on the proliferation, invasion and chemosensitivity of glioma cells. Method: CCK-8 cell proliferation assays and Transwell assays were employed to determine the effect of Polyphyllin Ⅱ on the proliferation and invasion of glioma cells (T98G and LN18), respectively. The expression of E-cadherin, Snail and O6-methylguanine DNA methyltranferase (MGMT) were quantified by Western blot analysis. Results: Polyphyllin Ⅱ could inhibit the proliferation of glioma cells in a time- and does-dependent manner. The half maximal inhibitory concentration (IC(50)) of T98G at 24 h, 48 h and 72 h were (5.82±0.32), (3.57±0.07) and (1.48±0.35) µmol/L, respectively. The IC(50) of LN18 at 24 h, 48 h and 72 h were (6.83±0.11), (4.28±0.29), (2.66±0.22) µmol/L, respectively. After being treated with 2 µmol/L, 4 µmol/L and 6 µmol/L Polyphyllin Ⅱ for 24 h, the percentage of invasive cell area in the chamber area was lower than those in T98G and LN18 control groups (P<0.05). Western blot analysis showed that compared with glioma cells without Polyphyllin Ⅱ treatment, the expression of E-cadherin in T98G and LN18 was higher (F=85.56, P<0.05; F=60.80, P<0.05), but the expression of snail was lower (F=25.34, P<0.05; F=48.28, P<0.05). When temozolomide was used in combination with Polyphyllin Ⅱ at different concentrations, the coefficient of drug interaction (CDI) was less than 1. Western blot showed that MGMT expressions in T98G and LN18 were inhibited compared with glioma cells without Polyphyllin Ⅱ treatment (F=40.38, P<0.05; F=48.44, P<0.05). Conclusion: Polyphyllin Ⅱ can inhibit the proliferation and invasion of glioma cells, and improve its sensitivity to Temozolomide.

[Preliminary study on the application of abdominal aortic balloon occlusion in the treatment of cesarean scar pregnancy].

Objective: To explore the clinical value by analyzing the application of abdominal aortic balloon occlusion in the uterine curettage treatment for patients with cesarean scar pregnancy (CSP). Methods: Totally 42 CSP patients in the first Affiliated Hospital of Zhengzhou University were analyzed retrospectively, 21 cases in the observation group, placing the balloon catheter to the abdominal aorta under the renal artery under the digital substraction angiography(DSA), conducting curettage under hysteroscopy or uterine laparoscopy immediately, and making intermittent blockage in abdominal aorta blood flow during the surgery;21 patients in the control group, conducting uterine artery embolization (UAE) before operation, conducting curettage under hysteroscopy or uterine laparoscopy after 1-3 days. The fluoroscopy time under DSA, body surface radiation dose, intraoperative blood loss, operation time, incidence of postoperative adverse reactions, hospitalization time and follow-up menstruation were comparatively analyzed. Results: All patients operated and retained the uterus successfully. In the control group, all 21 patients had different degrees of fever, pain and other symptoms after UAE. In the observation group and control group, the fluoroscopy time and body surface radiation dose under DSA respectively were (7.4±1.4) s, (5.4±1.1) mGy and (1 142.8±315.5) s, (1 442.0±300.0) mGy (both P<0.01);the average amount of intraoperative blood loss were (22±15), (19±14) ml (P>0.05), the time of uterine curettage were (37±20), (42±19) minutes (P>0.05);hospitalization time were (5.0±0.9), (7.7±1.3) days (P<0.01). The follow-up period was more than 3 months, no adverse reactions were observed in the observation group; 4 cases of menstrual reduction and 1 case of intrauterine adhesions were found in the control group. Conclusion: Abdominal aortic balloon occlusion and UAE could effectively reduce intraoperative bleeding in uterine curettage for patients with CSP; abdominal aortic balloon occlusion has significant reduction of the X-ray dose, shorter hospitalization time, and fewer adverse events comparing to UAE.

[Parotid CT imaging reporting and data system: A preliminary study].

OBJECTIVE: To establish a Parotid Imaging Reporting and Data System (PI-RADS) for CT diagnosis of the parotid gland neoplasms and to investigate the clinical applicable value and feasibility of PI-RADS. METHODS: Patients who had been diagnosed with primary parotid gland neoplasms and had received surgical treatments in Peking University School and Hospital of Stomatology during the period of January 2013 to December 2016 were included in this study. The diagnoses were confirmed by the postoperative pathological examinations in all the patients. The CT imaging data of all patients were retrospectively reviewed and analyzed by two readers in consensus. Imaging characteristics related to the parotid neoplasms were extracted and quantified. Based on comprehensive analysis of the imaging characteristics, the probabilities of the benign and malignant neoplasms were evaluated and classified into six grades, PI-RADS 1-6 (PI-RADS 1: normal parotid gland; PI-RADS 2: confidently benign lesions; PI-RADS 3: probably benign lesions without confirmed evidence of malignancy; PI-RADS 4: suspected malignancy without sufficient evidence of malignancy; PI-RADS 5: confidently malignant lesions; PI-RADS 6: lesions with confirmed pathological evidence of malignancy). RESULTS: A total of 897 patients with 1 003 parotid lesions were included. The lesions included 905 benign and 98 malignant lesions. The proportions of the malignancies in PI-RADS 2, PI-RADS 3, PI-RADS 4 and PI-RADS 5 according to the two readers in consensus were 0.4%, 5.7%, 35.5% and 96.7% respectively. The overall Cohen's Kappa test showed medium consistency between the two independent researchers (κ=0.614, P<0.001, 95%CI: 0.569-0.695). Pearson Chi-square test showed that the proportions of malignancies increased with the diagnostic PI-RADS grades (Cochran-Armitage trend test, Z=-15.579, P<0.001). The results of Pearson Chi-square tests showed significant differences between the grades [PI-RADS 2 and 3 (χ²=12.048, P=0.001); PI-RADS 3 and 4 (χ²=75.231, P<0.001); PI-RADS 4 and 5 (χ²=32.266, P<0.001)]. CONCLUSION: PI-RADS can be used to evaluate the risk of malignancy and will be helpful to improve the imaging diagnosis and clinical treatment of parotid gland neoplasms.

[Analysis of clinical, pathological features and therapeutic treatments in predicting prognosis of elderly glioblastomas].

Objective: This study was designed to investigate prognostic factors and the potential relationship between the expression of Ki67 and IDH of glioblastoma in the elderly (≥ 65 years old) and the clinical factors such as gender, the KPS score and treatments including surgical resection, radiotherapy and chemotherapy and the prognosis of such patients. Methods: Fifty-four elderly patients (≥ 65 years old) with glioblastoma admitted to the First Affiliated Hospital of Zhengzhou University from 2013 to 2018 were enrolled in this study. The expression of Ki67 was detected by immunohistochemical SP method and the mutation of IDH was detected by Sanger sequencing. Finally, statistical analysis was performed to determine whether Ki67, the mutation of IDH, gender, the KPS score and the extent of resection, radiotherapy and chemotherapy were associated with the clinical prognosis of the patients. Results: Of the 54 elderly patients with glioblastoma, none was detected with IDH mutation. Univariate analysis showed that Ki67(P=0.033), the KPS score (P=0.008), the extent of resection (P<0.001) were factors influencing the prognosis of elderly patients with glioblastoma. Patients receiving postoperative adjuvant radiotherapy (P=0.002) and chemotherapy (P=0.034) had longer survival time. There was no significant correlation between gender (P=0.467) and prognosis. Multivariate analysis demonstrated that radiotherapy (OR 2.446, P=0.009) and the extent of resection (OR 6.976, P<0.001) were independent prognostic factors. Conclusions: No IDH mutation was detected in all the patients in this study, indicating that IDH mutation is indeed rare in elderly glioblastoma, which suggests that geriatric population often harbor a molecular phenotype with poor prognosis. Ki67, KPS score, the extent of resection, radiotherapy and chemotherapy were the factors influencing the prognosis of patients.

[Computed tomographic features of desmoplastic ameloblastoma of the jaw].

OBJECTIVE: To retrospectively analyze the clinical and CT imaging features of desmoplastic ameloblastomas (DA) in comparison with other types of ameloblastomas. METHODS: Patients diagnosed with ameloblastoma histopathologically in Peking University School and Hospital of Stomatology from July 2000 to August 2017 were reviewed to analyze the constituent ratios and characteristics of DA. CT imaging features of DA (28 cases) were investigated in comparison with consecutive cases of solid/multicystic and unicystic ameloblastomas. The following imaging perspectives were analyzed: the border, internal structure, three-dimensional shape, tooth, the periodontium, the cortex and the expansion of the tumors. CT values were measured in the region of interest for quantitative analysis. RESULTS: Among the 1 269 cases of ameloblastomas, 50 (3.9%) were DA, which showed predilections for males (74.0%). The average age of DA was about 43.9 years old, which was higher than the other two types. The anterior incisorcanine region (62.0%) and premolar region (30.0%) were most frequently affected. The incidence rate of DA in mandibule was 56.0% (28/50), which was slightly higher than that of maxilla (44.0%). The DA characteristically showed scallop border and honeycomblike or soapbubble internal structure with bone formation on CT. The mean ratios of height to mesiodistal and buccal-lingual to mesio-distal distances were 0.76 and 0.63, which were higher than the other two types. According to the degree of internal bone formation, three subtypes of DA could be observed: densely ossifying type (I), honeycomb/soap bubble type (II) and sparsely ossifying type (III). The means and standard deviations of CT values of DA were significantly higher than those of the other two types, which were (488.8±164.0) HU (type I), (171.7±102.8) HU (type II), (42.1±8.8) HU (type III). CONCLUSION: CT is helpful for diagnosis of DA, which shows as solid tumor with varying degrees of internal ossification.