Promotion of Hernia Repair with High-Strength, Flexible, and Bioresorbable Silk Fibroin Mesh in a Large Abdominal Hernia Model

The use of synthetic surgical meshes for abdominal hernia repair presents numerous challenges due to insufficient mechanical strength, nonabsorbability, and implant rigidity that leads to complications including chronic inflammatory reactions and adhesions. In this study, a naturally derived, high-strength, flexible, and bioresorbable silk fibroin mesh was developed by knitted textile engineering and biochemical manipulation. The mechanical properties of the mesh were optimized with the trial of different surface coating methods (thermal or chemical treatment) and 12 different knit patterns. Our silk fibroin mesh showed sufficient tensile strength (67.83 N longitudinally and 62.44 N vertically) which afforded the high mechanical strength required for abdominal hernia repair (16 N). Compared to the commonly used commercial nonabsorbable and absorbable synthetic meshes (Prolene mesh and Ultrapro mesh, respectively), the developed silk fibroin mesh showed advantages over other meshes, including lower elongation rate (47.14% longitudinally and 67.15% vertically, <i>p</i> < 0.001), lower stiffness (10–1000 fold lower, <i>p</i> < 0.001), and lower anisotropic behavior (λ = 0.32, <i>p</i> < 0.001). In a rat model of large abdominal hernia repair, our mesh facilitated effective hernia repair with minimal chronic inflammation which gradually decreased from 15 to 60 days postoperation, as well as lower adhesion formation rate and scores compared to control meshes. There was more abundant and organized collagen deposition, together with more pronounced neovascularization in the repaired tissue treated with silk fibroin mesh as compared to that treated with synthetic meshes. Besides, the silk fibroin mesh gradually transferred load-bearing responsibilities to the repaired host tissue as it was bioresorbed after implantation. Its isotropic architecture favored an ease of use during operations. In summary, our findings indicate that the use of knitted silk fibroin mesh provides a safe and effective alternative solution for large abdominal hernia repairs as it overcomes the prevailing limitations associated with synthetic meshes

Data_Sheet_1_Association between microbiological risk factors and neurodegenerative disorders: An umbrella review of systematic reviews and meta-analyses.PDF

The role of microbiological factors in the development of neurodegenerative diseases is attracting increasing attention, while the relationship remains debated. This study aimed to comprehensively summarize and evaluate the associations between microbiological factors and the risk of neurodegenerative disorders with an umbrella review. PubMed, Embase, and the Cochrane library were used to search for papers from the earliest to March 2021 for identifying meta-analyses and systematic reviews that examined associations between microbiological factors and neurodegenerative diseases. AMSTAR2 tool was employed to evaluate the methodical quality of systematic reviews and meta-analyses. The effect size and 95% confidence interval (95% CI) were recalculated with a random effect model after the overlap was recognized by the corrected covered area (CCA) method. The heterogeneity of each meta-analysis was measured by the I2 statistic and 95% prediction interval (95% PI). Additionally, publication bias and the quality of evidence were evaluated for all 37 unique associations. Only 4 associations had above the medium level of evidence, and the rest associations presented a low level of evidence. Among them, helicobacter pylori (HP), infection, and bacteria are associated with Parkinson's disease (PD), and the other one verifies that periodontal disease is a risk factor for all types of dementia. Following the evidence of our study, eradication of HP and aggressive treatment of periodontitis are beneficial for the prevention of PD and dementia, respectively. This umbrella review provides comprehensive quality-grade evidence on the relationship between microbial factors and neurodegenerative disease. Regardless of much evidence linking microbial factors to neurodegenerative diseases, these associations are not necessarily causal, and the evidence level is generally low. Thus, more effective studies are required.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/#searchadvanced, PROSPERO, identifier: CRD42021239512.</p