Differences in Gut Microbiota between Healthy Individuals and Patients with Perianal Abscess before and after Surgery

Surgery is the most important treatment for perianal abscesses. However, the gut microbiota of patients with perianal abscess and the effects of perianal abscess on the gut microbiota after surgery are unknown. In this study, significant changes in interleukin 6 and tumor necrosis factor-α in the blood of healthy subjects, patients with perianal abscesses, and patients after perianal abscess surgery were identified. 16S rRNA gene sequencing technology was used to detect the changes in the gut microbiota among 30 healthy individuals and 30 patients with perianal abscess before and after surgery. Venn diagrams and alpha diversity analyses indicated differences in the abundance and uniformity of gut microbiota between the healthy individuals and patients with perianal abscesses before and after surgery. Beta diversity analysis indicated that the grouping effects among the control, abscess, and surgery groups were good. The classification and compositional analysis showed significant differences in the gut microbiota between healthy individuals and patients with perianal abscesses before and after surgery. LEfSe analysis, random forest analysis, and ROC curve analysis showed that Klebsiella (AUC=0.7467) and Bilophila (AUC=0.72) could be potential biomarkers for the diagnosis of perianal abscess. The functional prediction results showed that the differential microbiota is significantly enriched in the pathways related to nutrition and drug metabolism. This study may have important implications for the clinical management and prognostic assessment of patients with perianal abscesses

Immunotherapy and Antivascular Targeted Therapy in Patients’ Treatment with Concurrent Malignant Tumors after Organ Transplantation: Opportunity or Challenge

Objective. To analyze the therapeutic effects and organ rejection of anti-PD-1 immunotherapy or antivascular targeting therapy on patients with combined malignancies after organ transplantation. Methods. We collected retrospective studies on “post-transplantation, cancer, immunotherapy, and vascular targeting therapy” in Embase, Wanfang database, Cochrane Library, VIP databases, CNKI, and PubMed, and the case data were organized and analyzed. Results. Data from only 40 papers met our requirements, which included 2 literature reviews, 4 original researches, and 34 case reports from 2016 to 2020. A total of 40 studies involving 66 patients were included, who were divided into 3 groups (patients using CTLA-4 inhibitors, group 1; patients who received sequential or concurrent anti-PD-1 and anti-CTLA-4 therapy, group 2; and patients using PD-1/PD-L1 inhibitors, group 3). There was no statistical difference in patients’ DCR between the three groups (P>0.05). Also, compared with group 2, there was no statistically significant difference in recipient organ rejection in group 1 and group 3 (P>0.05). The DCR rate for antivascular targeted therapy is approximately 60%. Conclusions. Immunotherapy should be carefully selected for patients with combined malignancies after organ transplantation. Antivascular targeted therapy is one of the options worth considering; the risk of side effects of drug therapy is something that needs to be closely monitored when combined with immunotherapy

An enhanced thermo-actuated shape memory polymer composite coupled with elastomer

A new enhanced thermo-actuated shape memory polymer (SMP) composite PE-NBR was developed and its properties were compared with traditional SMPs. The numerical simulation and experiment study on packer element were performed by the way of newly developed constitutive model. The functional composite system with shape memory effect is mainly composed of polyolefin acting as shape memory component and particle-filled elastomer acting as modified enhancement component. The PE-NBR system has advantages over traditional SMP with tensile strength of 14.3 MPa, hardness of 71 and shape recovery ratio of 95%. The ratio of polyolefin in the system can be adjusted from 20% to 90% and that of elastomer can be adjusted from 10% to 70%. The constitutive model with rubber plastic blending for PE-NBR system based upon mesomechanics and macroscopic properties of materials is used to meet the numerical study requirements of large-deformation, temperature-dependence and nonlinear composites. The rating pressure of packer element using PE-NBR system is more than 10 MPa and the maximum of contact pressure is obtained in the location which is 60 mm away from the end surface of the element. Key words: shape memory polymer, composite material, mesomechanics, constitutive model, polyolefin, elastomer, packe