Objective To study the effect of UHRF1 expression inhibition by RNA interference on the radiosensitivity of esophageal cancer cell line TE-1 and its mechanism.Methods Short hairpin RNA (shRNA) targeting UHRF1 gene was introduced into TE-1 cells by lentivector-mediated transfer.The cells were divided into three groups:non-transfected group,negative control (NC)-shRNA-transfected group,and UHRF1-shRNA-transfected group.The mRNA and protein expression levels of UHRF1 in TE-1 cells were measured by RT-PCR and Western blot before and after transfection.After transfection and X-ray radiation,the radiosensitivity of TE-1 cells was evaluated by colony formation assay; the cell cycle and cell apoptosis were determined by flow cytometry; the γ-H2AX (as a marker of DNA damage) level was measured by Western blot.Results After transfection with UHRF1-shRNA,the mRNA and protein expression levels of UHRF1 were significantly decreased in TE-1 cells,as compared with those in the NC-shRNA-transfected group and non-transfected group (0.11 vs 0.96 and 0.98,F =124.21,P =0.000;0.10 vs 0.89 and 0.94,F =125.25,P =0.000).The UHRF1-shRNA-transfected group had sensitization enhancement ratios of 1.53 (D0 ratio) and 1.95 (Dq ratio).X-ray radiation could cause G2/M arrest and increase apoptotic rate and γ-H2AX expression in TE-1 cells.Compared with the two control groups,the UHRF1-shRNA-transfected group showed significantly less G2/M arrest (F =500.15,P =0.000),a significantly higher apoptotic rate (F =100.10,P =0.000),and significantly higher residual γ-H2AX expression (F =61.00,P =0.000) at 24 hours after X-ray radiation.Conclusions RNA interference can effectively inhibit the UHRF1 expression and enhance the radiosensitivity of TE-1 cells.The mechanism may be related to cell cycle regulation,cell apoptosis,and DNA damage repair.

Objective To investigate the local-regional recurrence in thoracic esophageal cancer after radical surgery including two-field lymph node dissection and provide evidence for postoperative radiotherapy. Methods We reviewed local-regional recurrence for 134 cases with esophageal squamous cell carcinoma after radical surgery from 2004 to 2009. Results In 134 cases, lymph node metastasis rate,anastomosis recurrence rate and tumor bed recurrence rate was 94. 0%, 9. 7% and 3.7%, respectively. As to the 126 cases with lymph node metastasis, significant difference was detected between mediastinal metastasis, supraclavicular metastasis and abdominal lymph node metastasis (80. 2%, 43.7% and 13.5%,respectively, χ2= 113. 15, P = 0. 000). Furthermore, the relative metastasis rate in upper mediastinum,middle mediastinum and the lower mediastinum was 73.8%, 39.7% and 1.6%, respectively, the difference was statistically significant ( χ2 = 139. 11, P = 0. 000 ). Significant difference was identified between right and left supraclavicular lymph node metastasis (31.7% vs 16. 7%, χ2= 7. 81, P = 0. 005 ).To confirm the analysis above,lymph node metastasis rate of left recurrent laryngeal nerve nodes, (including region 1L, 2L, 4L and 5) ,right recurrent laryngeal nerve nodes, azygos nodes, subcarinal nodes, and 2R region was 38.9%, 43.7%, 15.1%, 34.1% and 25.4%, respectively. Conclusions The main characteristics of local-regional recurrence may be lymph node metastasis for esophageal squamous cell carcinoma after radical surgery. On the contrary, tumor bed recurrence is rare. Dangerous regions include supraclavicular nodes, recurrent laryngeal nerve nodes, azygos nodes as well as subcarinal nodes.

ObjectiveTo evaluate correlation factors of cervical lymph nodes metastasis in thoracic esophageal carcinoma.MethodsLocal-regional metastasis of lymph node for 126 cases with esophageal squamous cell cancer after surgery from 2004 to 2009 were reviewed.Risk factors of cervical lymph nodes metastasis were examined by multiple Logistic regression analysis.ResultsIn 126 cases,supraclavicular lymph node metastasis rate was 43.7％ (55/126).By logistic regression,none of the primary site,T stage,N stage,histological grade,lymph node metastasis rate,lymph node metastasis degree and number of lymph nodes metastatic field was not the high risk of cervical lymph nodes metastasis.In addition,multivariate analysis found that lymph node metastasis in mediastinum region 1 was high risk factor for lymph node metastasis of region 1 ( x2 =12.14,9.27,P =0.000,0.002),lymph node metastasis in region Ⅲ and region 2 were high risk factors for lymph node metastasis of region Ⅱa ( x2 =14.56,8.27,8.02,3.93,P =0.000,0.004,0.005,0.047 ).ConclusionMediastinal para-recurrent nerve lymph node metastasis is a significant predictor for cervical lymph nodes metastasis.

Objective To evaluate the effect of GTV volume on response of esophageal carcinoma.Methods From Jan.2004 to Dec.2008,72 cases newly diagnosed N0 stage thoracic esophageal carcinomas were included in this retrospective study.All treatment plans were set up and designed by CT simulator and 3D TPS.They received dose 56-70 Gy/27-33F/6-7w with 6MV X-ray.The GTV,the tumor length and maximum diameters were measured on the treatment planning system with the X-ray.RECIST standard was applied to evaluate the radiotherapy response of esophageal carcinoma.The effectiveness of related prognostic factors on survival was evaluated by univariate analyses.Results The short-term response with CR were 79％ with length ＜ 5 cm,48％ with 5-7 cm and 26％ with length ＞7 cm(P =0.003).The 1-,2-,3-and 5-year survival rates were 93％,79％,69％,69％ ; 91％,61％,46％,46％ and 80％,46％,28％,22％ (P =0.037).The short-term response with CR were 56％ with maximum diameters ≤3 cm and 33％ with maximum diameters ＞ 3 cm(P =0.033).The 1-,2-,3-and 5-year survival rates were 91％,72％,55％,37％ and 80％,45％,30％,30％ (P =0.037).The short-term response with CR were 52％ with GTV volume≤40 cm3 and 30％ with GTV volume ＞40 cm3(P =0.059).The 1-,2-,3-and 5-year survival rates were 91％,67％,51％,41％ and 80％,43％,27％,27％ (P =0.047).In the multivariate analysis,the length of GTV was likely to be the most important factor for the short-term response(P =0.005,0.014).Conclusions GTV volume,the tumor length and maximum diameters are factors for short-term response of N0 stage esophageal carcinoma.The GTV length is independent prognostic factor.The GTV length is the worse the prognosis will be.

Orthopedic robots, as intelligent medical devices, have achieved good outcomes in clinical application in some orthopedic surgeries. Artificial intelligence (AI) has played an important role in the development of orthopedic robots due to its powerful capabilities of information processing and decision-making. The developing trends of orthopedic robotics are automation and intelligentization. Since AI has demonstrated great advantages in preoperative planning, an increasing number of researchers have been devoted to AI application in intraoperative navigation by an orthopedic robot. This paper outlines the exploratory efforts in applying AI technology to the intraoperative navigation assisted by an orthopedic robot, describes the advantages of AI in improving accuracy and reducing radiation, and forecasts research prospects in application of AI technology to orthopedic robots based on the current situation.

Femoral fracture is a common type of fracture in clinical practice, and poor fracture reduction may lead to malunion and dysfunction. At present, traditional reduction with manipulation and intramedullary nailing are the mainstream treatments, but there exist problems such as X-ray exposure or poor reduction. Fracture reduction robots are of positive significance in improving the safety of surgical treatment of femur fracture, avoiding repetitive operations and poor alignment, and shortening the patients′ postoperative recovery time. Navigation algorithm is the key to achieve the function of femoral repositioning. Understanding the advantages and disadvantages that various types of navigation algorithms demonstrated in femoral reduction applications is important for giving full play to the value of fracture reduction robots in femoral reduction. Therefore, the authors reviewed the research progress in existing robot navigation algorithms applied in femoral fracture repositioning from the following four aspects, including image alignment algorithm, algorithm for establishing the target pose of femoral repositioning, algorithm for compensating the mechanical error, and algorithm for path planning, hoping to provide a reference for the application and research of navigation algorithms of fracture reduction robots.

Bone defects, often accompanied by osteomyelitis, soft tissue contusions, etc, are facing lengthy treatment process and slow healing, seriously jeopardizing the structural integrity of the human bone tissue. Currently, the main treatment for bone defects involves autologous or allogeneic bone transplant. However, autologous bone transplant poses problems, including long surgical duration, increased pain and complications such as infections. Additionally, immune rejection reactions also limit the effectiveness of allogeneic bone transplant of the same species. Bone scaffolds have become a potential alternative for bone transplant, but problems such as sharp edges of the scaffolds and poor compatibility with human tissues exist. Triply periodic minimal surface (TPMS), with an average curvature of zero has lower levels of stress concentration and the ability to be precisely expressed with mathematical formulas, compared with other structures. Its application in bone scaffolds attracts much attention, but there is currently a lack of comprehensive understanding of the impacts of different types of TPMS on the performance of bone scaffolds. With this purpose, the authors reviewed the research progress in the impacts of different types of TPMS on the performance of bone scaffolds, providing a reference for the construction of bone scaffolds.

Objective To analyze the risk factors of enteral nutrition intolerance in elderly patients with severe pneumonia(SP)in intensive care unit(ICU)and construct its prediction model.Methods A total of 140 elderly patients with severe pneumonia in ICU ward of the First Affiliated Hospital of Ningbo University from January 2021 to December 2022 were selected.According to the tolerance of enteral nutrition,they were divided into tolerance group(n=82)and intolerance group(n=58).Univariate and multivariate Logistic regression analysis was used to analyze the risk factors of enteral nutrition intolerance in elderly patients with severe pneumonia in ICU.The risk prediction model was constructed,and the receiver operating characteristic(ROC)curve was drawn to evaluate the prediction effect of the model.Results Multivariate Logistic regression analysis showed that acute gastrointestinal injury(AGI),intra-abdominal pressure(IAP),and the use of antibiotics≥2 were independent influencing factors of enteral nutrition intolerance in elderly patients with severe pneumonia in ICU(P<0.05).The Hosmer-Lemeshow goodness-of-fit test was used to evaluate the fitting effect of the equation.The area under the curve was 0.867(95%CI:0.750-0.984),the sensitivity was 87.8%,and the specificity was 85.1%.Conclusion The risk prediction model constructed in this study can effectively predict the risk of enteral nutrition intolerance in elderly patients with severe pneumonia in ICU.

Objective To compare the therapeutic effects between three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) in patients with stage Ⅱ/Ⅲ esophageal cancer and investigate the prognostic factors.Methods Medical record of 2 132 patients with stage Ⅱ/Ⅲ esophageal cancer who underwent definitive radiotherapy with/without chemotherapy in 10 hospitals from January 2002 to December 2016 from were retrospectively analyzed.Among these patients,37.9％ of them were aged ≥ 70 years,33.9％ with neck and upper esophageal tumors and 66.1％ with middle and lower esophageal and borderline tumors.The median gross tumor volume (GTV) and lymph node gross tumor volume (GTVnd) was 41.6 cm3.Among them,32％ were stage Ⅱ] and 68％ were stage Ⅲ.A total of 723 patients received 3DCRT and 1 409 cases received IMRT.Patients received an equivalent dose in 2 Gy (EQD2) ≥ 60 Gy accounted for 86.1％,and 41.1％ of them received concurrent chemoradiotherapy.Results The median follow-up time was 60.8 months.The 1-,3-and 5-year overall survival (OS) of all patients was 73.9％,41.7％ and 32.6％,and the 1-,3-and 5-year progression-free survival (PFS) was 62.2％,37.3％ and 32％,respectively.Multivariate analysis demonstrated that age,primary tumor location,clinical stage,tumor target volume,EQD2 and concurrent chemoradiotherapy were the independent prognostic factors for OS.Age,primary tumor location,clinical stage,tumor target volume and EQD2 were the independent prognostic factors for PFS.The OS and PFS did not significantly differ among the low-risk,low-/moderate-risk,moderate-/high-risk and high-risk groups according to age≥70 years,tumor diameter＞5 cm,tumor volume ≥41.6 cm3 and stage Ⅲ (P＜0.001).After the propensity score matching (PSM) method,neither 3DCRT nor IMRT yielded significant advantages in OS or PFS (P=0.971;P=0.658).However,IMRT tended to yield survival benefits in low-risk patients (P=0.125).Conclusions Both 3DCRT and IMRT yield relatively high OS rate in patients with stage Ⅱ/Ⅲ esophageal cancer.The prognosis model established in this investigation can properly predict the survival of patients.Low-risk patients tend to obtain survival benefits from IMRT.

Objective To retrospectively analyze the effect of tumor length on the prognosis in stage Ⅱ/Ⅲ esophageal squamous cell carcinoma (ESCC) patients treated with definitive radiotherapy and to evaluate the role of tumor length in clinical stage for non-operative ESCC patients.Methods The data of 2 086 ESCC patients who were treated with definitive radiotherapy from 2002 to 2016 in 10 hospitals (3JECROG) were analyzed.The effect of tumor length on overall survival (OS) was analyzed and stratified analysis of tumor length was done in different stages of ESCC.Results The median OS and median progression-free survival (PFS) time of the whole group were 25.6 months and 18.2 months respectively.The Cox multivariate analysis showed that treatment moda,aga,alinical stage and tumor length were independent prognostic factors.The median,1-,3-,and 5-year OS were 28.9 months,77.3％,45.0％,and 36.3％ versus 21.9 months,69.9％,37.9％,and 28.1％ for patients with ≤ 5 cm and patients ＞ 5 cm respectively (P＜0.05).For stage Ⅱ patienta,abe median OS were 42.1 and 38.9 months respectively in ≤ 5 cm group and＞5 cm group (P=0.303).And for stage Ⅲ patienta,abe median OS were 23.9 and 19.3 months respectively in ≤5 cm group and＞5 cm group (P＜0.001).The median OS with N1was 24.1 and 18.4 montha,aespectively in ≤5 cm group and＞5 cm group (P＜0.001).Conclusions The tumor length was an independent prognostic factor for stage Ⅱ/Ⅲ patients treated definitive radiotherapy.The tumor length may be helpful in clinical staging of ESCa,aspecially for stage Ⅲ and N1.