RESUMO
BACKGROUND: The aim of this study was to develop a simple method for closure of a perforated peptic ulcer, making it more accessible for laparoscopic surgery. METHODS: An experimental pilot study was performed using five male Wistar rats. The perforation was closed by a bioabsorbable patch made of lactide-glycolid-caprolactone fixed with glue onto the outside of the stomach. RESULTS: Postoperatively, there were no signs of leakage or other complications. Histologically, there were no signs of inflammation on the inside of the stomach, and there was a 50% reduction of the perforation each successive postoperative week. No adverse reactions because of the degradable material or glue were observed. CONCLUSIONS: Treatment of a perforated peptic ulcer by placing a patch of biodegradable material like a "stamp" on the outside of the stomach is a feasible option.
Assuntos
Implantes Absorvíveis , Úlcera Péptica Perfurada/cirurgia , Animais , Laparotomia , Masculino , Úlcera Péptica Perfurada/patologia , Poliésteres , Ratos , Ratos Wistar , Reoperação , Fatores de TempoRESUMO
We investigated possible cytotoxic effects, biocompatibility, and degradation of a hyaluronan-based conduit for peripheral nerve repair. We subjected the conduits to an in vitro fibroblast cytotoxicity test and concluded that the conduits were not cytotoxic. Subsequently, we implanted the conduits subcutaneously in rats, in order to investigate tissue reactions and biodegradation. Initially, a fibrin matrix was formed around the material, while the surroundings were relatively quiet. Macrophages (MØ) migrated to the conduits and formed giant cells next to the material after 5 days. The maximum presence of MØ was found after 3-6 weeks. The appearance of MHC class II cells showed a similar pattern. Highest numbers of giants reached a maximum after 6-12 weeks. Angiogenesis was started in the surroundings of the hyaluronan-based conduit within a few days. Massive ingrowth of blood vessels into the biomaterial was found after 6 weeks as well as cellular ingrowth into the lumen of the tube. At that time the tubular structure of the conduit was lost and loose biomaterial fibers were observed. The results show that a hyaluronan-based conduit is not cytotoxic and shows good biocompatibility. Such a conduit may be suitable as a guide in peripheral nerve repair.
Assuntos
Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Neurônios/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Divisão Celular , Linhagem Celular , Fibrina/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Receptores de Hialuronatos/biossíntese , Imuno-Histoquímica , Técnicas In Vitro , Macrófagos/metabolismo , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Neovascularização Patológica , Regeneração Nervosa , Tecido Nervoso , Nervos Periféricos/patologia , Sistema Nervoso Periférico/metabolismo , Ratos , Ratos Wistar , Fatores de TempoRESUMO
Recovery of nerve function was evaluated after bridging a 15 mm sciatic nerve gap in 51 rats with a biodegradable poly(DL-lactide-epsilon-caprolactone) nerve guide. Recovery of function was investigated by analysing the footprints, by analysing video recordings of gait, by electrically eliciting the withdrawal reflex, by nerve conduction velocity and by electromyography (EMG). Sensory nerve function recovered as measured by electrostimulation. Motor nerve function partly recovered but electromyograms remained abnormal throughout the study. We conclude that functional reinnervation by regenerating axons occurs after bridging a 15 mm nerve gap with a biodegradable poly(DL-lactide-epsilon-caprolactone) nerve guide, but the walking patterns remain abnormal. Video analysis is a useful tool to record and analyse the walking patterns of rats. Further studies are necessary to investigate the possibility of obtaining selective reinnervation of specific muscles.
