OBJECTIVE: To evaluate the host- and biomechanical response to a fully absorbable poly-4-hydroxybutyrate (P4HB) scaffold in comparison with the response to polypropylene (PP) mesh. DESIGN: In vivo animal experiment. SETTING: KU Leuven Center for Surgical Technologies. POPULATION: Fourteen parous female Mule sheep. METHODS: P4HB scaffolds were surgically implanted in the posterior vaginal wall of sheep. The comparative PP mesh data were obtained from an identical study protocol performed previously. MAIN OUTCOME MEASURES: Gross necropsy, host response and biomechanical evaluation of explants, and the in vivo P4HB scaffold degradation were evaluated at 60- and 180-days post-implantation. Data are reported as mean ± standard deviation (SD) or standard error of the mean (SEM). RESULTS: Gross necropsy revealed no implant-related adverse events using P4HB scaffolds. The tensile stiffness of the P4HB explants increased at 180-days (12.498 ± 2.66 N/mm SEM [p =0.019]) as compared to 60-days (4.585 ± 1.57 N/mm) post-implantation, while P4HB degraded gradually. P4HB scaffolds exhibited excellent tissue integration with dense connective tissue and a moderate initial host response. P4HB scaffolds induced a significantly higher M2/M1 ratio (1.70 ± 0.67 SD, score 0-4), as compared to PP mesh(0.99 ± 0.78 SD, score 0-4) at 180-days. CONCLUSIONS: P4HB scaffold facilitated a gradual load transfer to vaginal tissue over time. The fully absorbable P4HB scaffold, in comparison to PP mesh, has a favorable host response with comparable load-bearing capacity. If these results are also observed at longer follow-up in-vivo, a clinical study using P4HB for vaginal POP surgery may be warranted to demonstrate efficacy. TWEETABLE ABSTRACT: Degradable vaginal P4HB implant might be a solution for treatment of POP.

• Klíčová slova
• biomechanics, degradable scaffold, host response, pelvic organ prolapse, poly-4-hydroxybutyrate, vaginal surgery,
• MeSH
• biomechanika MeSH
• chirurgické síťky * škodlivé účinky   MeSH
• hydroxybutyráty MeSH
• lidé MeSH
• ovce MeSH
• polypropyleny * MeSH
• vagina chirurgie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydroxybutyráty MeSH
• polypropyleny * MeSH

BACKGROUND: There is an urgent need to develop better materials to provide anatomical support to the pelvic floor without compromising its function. OBJECTIVE: Our aim was to assess outcomes after simulated vaginal prolapse repair in a sheep model using three different materials: (1) ultra-lightweight polypropylene (PP) non-degradable textile (Restorelle) mesh, (2) electrospun biodegradable ureidopyrimidinone-polycarbonate (UPy-PC), and (3) electrospun non-degradable polyurethane (PU) mesh in comparison with simulated native tissue repair (NTR). These implants may reduce implant-related complications and avoid vaginal function loss. DESIGN, SETTING, AND PARTICIPANTS: A controlled trial was performed involving 48 ewes that underwent NTR or mesh repair with PP, UPy-PC, or PU meshes (n=12/group). Explants were examined 60 and 180 d (six per group) post-implantation. INTERVENTION: Posterior rectovaginal dissection, NTR, or mesh repair. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Implant-related complications, vaginal contractility, compliance, and host response were assessed. Power calculation and analysis of variance testing were used to enable comparison between the four groups. RESULTS: There were no visible implant-related complications. None of the implants compromised vaginal wall contractility, and passive biomechanical properties were similar to those after NTR. Shrinkage over the surgery area was around 35% for NTR and all mesh-augmented repairs. All materials were integrated well with similar connective tissue composition, vascularization, and innervation. The inflammatory response was mild with electrospun implants, inducing both more macrophages yet with relatively more type 2 macrophages present at an early stage than the PP mesh. CONCLUSIONS: Three very different materials were all well tolerated in the sheep vagina. Biomechanical findings were similar for all mesh-augmented repair and NTR. Constructs induced slightly different mid-term inflammatory profiles. PATIENT SUMMARY: Product innovation is needed to reduce implant-related complications. We tested two novel implants, electrospun and an ultra-lightweight polypropylene textile mesh, in a physiologically relevant model for vaginal surgery. All gave encouraging outcomes.

• Klíčová slova
• Biocompatibility, Biomaterials, Biomechanics, Pelvic organ prolapse, Vaginal surgery,
• MeSH
• biokompatibilní materiály MeSH
• chirurgické síťky * MeSH
• gynekologické chirurgické výkony MeSH
• modely nemocí na zvířatech MeSH
• modely u zvířat MeSH
• ovce MeSH
• polypropyleny * MeSH
• prolaps dělohy chirurgie   MeSH
• protézy - design MeSH
• pyrimidinony MeSH
• testování materiálů MeSH
• textilie MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biokompatibilní materiály MeSH
• polypropyleny * MeSH
• pyrimidinony MeSH
• ureidopyrimidinone MeSH Prohlížeč

PURPOSE: Electrospun meshes may be considered as substitutes to textile polypropylene implants. We compared the host response and biomechanical properties of the rat abdominal wall following reinforcement with either polycaprolactone (PCL) modified with ureidopyrimidinone-motifs (UPy) or polypropylene mesh. METHODS: First we measured the response to cyclic uniaxial load within the physiological range both dry (room temperature) and wet (body temperature). 36 rats underwent primary repair of a full-thickness abdominal wall defect with a polypropylene suture (native tissue repair), or reinforced with either UPy-PCL or ultra-light weight polypropylene mesh (n = 12/group). Sacrifice was at 7 and 42 days. Outcomes were compliance of explants, mesh dimensions, graft related complications and semi-quantitative assessment of inflammatory cell (sub) types, neovascularization and remodeling. RESULTS: Dry UPy-PCL implants are less stiff than polypropylene, both are more compliant in wet conditions. Polypropylene loses stiffness on cyclic loading. Both implant types were well incorporated without clinically obvious degradation or herniation. Exposure rates were similar (n = 2/12) as well as mesh contraction. There was no reinforcement at low loads, while, at higher tension, polypropylene explants were much stiffer than UPy-PCL. The latter was initially weaker yet by 42 days it had a compliance similar to native abdominal wall. There were eventually more foreign body giant cells around UPy-PCL fibers yet the amount of M1 subtype macrophages was higher than in polypropylene explants. There were less neovascularization and collagen deposition. CONCLUSION: Abdominal wall reconstruction with electrospun UPy-PCL mesh does not compromise physiologic tissue biomechanical properties, yet provokes a vivid inflammatory reaction.

• Klíčová slova
• Biocompatibility, Biomechanics, Electrospun mesh, Hernia, Pelvic organ prolapse,
• MeSH
• biomechanika MeSH
• břišní stěna fyziologie   MeSH
• chirurgické síťky * MeSH
• fascie fyziologie   MeSH
• kosterní svaly fyziologie   MeSH
• krysa rodu Rattus MeSH
• polyestery MeSH
• potkani Sprague-Dawley MeSH
• pyrimidinony MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• polycaprolactone MeSH Prohlížeč
• polyestery MeSH
• pyrimidinony MeSH