Recursive partitioning staging system based on the log odds of the negative lymph node/T stage ratio in colon mucinous adenocarcinoma

BackgroundThis study aimed to investigate the prognostic significance of the log odds of negative lymph nodes/T stage ratio (LONT) and develop an efficient prognostic staging system using LONT in patients with colon mucinous adenocarcinoma (MAC).MethodsThis study included 5,236 patients diagnosed with colon MAC obtained from the Surveillance, Epidemiology, and End Results database. The Kaplan–Meier method, subgroup analysis, receiver operating characteristic (ROC) curve, and Cox proportional hazard regression model were used to determine the clinical outcomes. Recursive partitioning analysis (RPA) was used to develop a novel prognostic system.ResultsThe 1-, 3-, and 5-year ROC curves, used to predict cancer-specific survival (CSS) and overall survival (OS), demonstrated that the areas under the ROC curve for LONT were superior to those of pT, pN, and pTNM stages. Additionally, a lower LONT was correlated with worse clinical outcomes. The LONT classification efficiently differentiated the prognosis of patients in terms of OS and CSS. Multivariate Cox analyses revealed that LONT was an independent prognostic factor for both CSS and OS. Based on the pT stage and LONT, a novel prognostic staging system was developed using RPA, demonstrating a good prognostic predictive performance.ConclusionA lower LONT was associated with worse survival in patients with colon MAC. The pT stage and LONT-based prognostic staging system facilitated risk stratification in these patients

Double-stapled anastomosis without “dog-ears” reduces the anastomotic leakage in laparoscopic anterior resection of rectal cancer: A prospective, randomized, controlled study

BackgroundAnastomotic leakage (AL) is a major cause of postoperative morbidity and mortality in the treatment of colorectal cancer. The aim of this study was to investigate whether the resection of “dog-ears” in laparoscopic anterior resection of rectal cancer (called modified double-stapling technique, MDST) could reduce the rate of AL in patients with middle and high rectal cancer, as compared with the conventional double-stapling technique (DST).MethodsThe clinical data of 232 patients with middle and high rectal cancer were prospectively collected from September 2015 to October 2018. They were randomly divided into the MDST group (n = 116) and the DST group (n = 116) and the data were prospectively analyzed. Morbidity and AL rate were compared between the two groups.ResultsPatient demographics, tumor size, and time of first flatus were similar between the two groups. No difference was observed in the operation time between the two groups. The AL rate was significantly lower in the MDST group than in the DST group (3.4 vs. 11.2%, p = 0.032). The age and anastomotic technique were the factors associated with AL according to the multivariate analysis. The location of the AL in the DST group was further investigated, revealing that AL was in the same place as the “dog-ears” (11/13, 84.6%).ConclusionsOur prospective comparative study demonstrated that MDST have a better short-term outcome in reducing AL compared with DST. Therefore, this technique could be an alternative approach to maximize the benefit of laparoscopic anterior resection on patients with middle and high rectal cancer. The “dog-ears” create stapled corners potentially ischemic, since they represent the area with high incidence of AL.(NCT:02770911

Structure Design and Motion Control of a Hybrid Quadruped Robot with Wheels and Legs

As a type of modern bionic robot, the wheel-leg hybrid quadruped robot has become a popular research focus of related scholars both at home and abroad. This is due to its flexible motion performance and strong environmental adaptability. This article first summarises and analyses the related research results of the wheel-leg hybrid quadruped robot, especially focusing on the leg structure. Mirroring the movement characteristics of quadrupeds in nature and the characteristics of bone structure, a relatively novel wheel-leg hybrid quadruped robot wheel-leg structure is proposed. Based on the combination of the wheels and legs, a parallel mechanism is adopted as the structural design. The carrying capacity and overall rigidity of the robot are improved by replicating the composition of the skeletal structure of four-legged creatures in nature. At the same time, the kinematic model of the leg structure is established to analyse the movement characteristics of the robot. The kinematic and dynamic simulation of the single wheel-leg structure of the wheel-leg hybrid quadruped robot were performed using ADAMS software to verify the accuracy of the mathematical model. By setting two methods of sine drive and STEP function drive in ADAMS software, the designed gait sequence is simulated to verify the stability of the designed gait when walking. Provide reference basis for motion control. </p

Clinical analysis of metastatic characteristics of infrapyloric lymph nodes (No.206) and terminal ileum lymph nodes in patients with right colon cancer

Abstract Background D3 or complete mesocolic excision (CME) surgery has become a common surgical procedure for the treatment of colon cancer metastasis. Clinical misuse and overuse of lymph node dissection bring unnecessary burdens to patients. A detailed guidance for lymph node dissection in patients with T3 and T4 stage right colon cancer at different locations is urgently needed. Methods A retrospective study was performed. Patients received D3 or CME surgery were divided into ileocecal group, ascending colon group, and hepatic flexure group according to the 9th edition of the Japanese Society for Cancer of the Colon and Rectum guidelines. The distributions of lymph node metastases were analyzed according to tumor infiltration depth (T stage) and tumor location. Results The incidence of metastases in the paracolic area (or station), intermediate area, and main (or central) area was 38.4% (139/362), 12.7% (46/362), and 9.7% (35/362), respectively. The proportion of patients having No.206 and terminal ileum lymph nodes metastases was 7.7% (14/181) and 3.7% (9/244), respectively. No.206 lymph node metastasis is related to tumor location (χ2 = 7.955, p = 0.019) and degree of differentiation (χ2 = 18.99, p = 0.000), and terminal ileum lymph node metastasis is related to tumor location (χ2 = 6.273, p = 0.043). Patients with T3/T4 hepatic flexure cancer received radical right hemicolectomy in addition to No.206 lymph node dissection. Conclusion Radical right hemicolectomy and No.206 group lymph node dissection are necessary for T3 and T4 stage colon cancer therapy. </jats:sec

Design and Manufacture of Pneumatically Actuated Flexible Hand

A kind of bionic flexible hand was designed, and a pneumatically actuated finger bending scheme was proposed. It can imitate the human hand to complete a variety of complex work, e.g., grabbing fragile or irregular objects. The fabrication scheme of flexible fingers was proposed and the corresponding mold was designed. A finite element simulation analysis of flexible finger was conducted. The fabrication of flexible fingers was completed, and the feasibility of the fabrication scheme was proved. </p

Development and Validation of a Robust Pyroptosis-Related Signature for Predicting Prognosis and Immune Status in Patients with Colon Cancer

Background. Pyroptosis has been confirmed as a type of inflammatory programmed cell death in recent years. However, the prognostic role of pyroptosis in colon cancer (CC) remains unclear. Methods. Dataset TCGA-COAD which came from the TCGA portal was taken as the training cohort. GSE17538 from the GEO database was treated as validation cohorts. Differential expression genes (DEGs) between normal and tumor tissues were confirmed. Patients were classified into two subgroups according to the expression characteristics of pyroptosis-related DEGs. The LASSO regression analysis was used to build the best prognostic signature, and its reliability was validated using Kaplan–Meier, ROC, PCA, and t-SNE analyses. And a nomogram based on the multivariate Cox analysis was developed. The enrichment analysis was performed in the GO and KEGG to investigate the potential mechanism. In addition, we explored the difference in the abundance of infiltrating immune cells and immune microenvironment between high- and low-risk groups. And we also predicted the association of common immune checkpoints with risk scores. Finally, we verified the expression of the pyroptosis-related hub gene at the protein level by immunohistochemistry. Results. A total of 23 pyroptosis-related DEGs were identified in the TCGA cohort. Patients were classified into two molecular clusters (MC) based on DEGs. Kaplan–Meier survival analysis indicated that patients with MC1 represented significantly poorer OS than patients with MC2. 13 overall survival- (OS-) related DEGs in MCs were used to construct the prognostic signature. Patients in the high-risk group exhibited poorer OS compared to those in the low-risk group. Combined with the clinical features, the risk score was found to be an independent prognostic factor of CC patients. The above results are verified in the external dataset GSE17538. A nomogram was established and showed excellent performance. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the varied prognostic performance between high- and low-risk groups may be related to the immune response mediated by local inflammation. Further analysis showed that the high-risk group has stronger immune cell infiltration and lower tumor purity than the low-risk group. Through the correlation between risk score and immune checkpoint expression, T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) was predicted as a potential therapeutic target for the high-risk group. Conclusion. The 13-gene signature was associated with OS, immune cells, tumor purity, and immune checkpoints in CC patients, and it could provide the basis for immunotherapy and predicting prognosis and help clinicians make decisions for individualized treatment.</jats:p