polyester
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- MeSH
- aorta abdominalis chirurgie MeSH
- cévní protézy MeSH
- kathepsin D biosyntéza MeSH
- proteiny MeSH
- psi MeSH
- tyrosin MeSH
- zvířata MeSH
- Check Tag
- psi MeSH
- zvířata MeSH
Úvod: V chirurgii kýl břišní stěny jsou nejčastěji používány polyesterové a polypropylenové síťky. Jejich intraperitoneální implantace může vést k tvorbě adhezí s břišními útrobami s následnou poruchou pasáže nebo vznikem střevní píštěle. Některé kompozitní implantáty mohou snížit riziko tvorby adhezí. Cílem studie bylo posouzení vlastností a vhodnosti intraperitoneální implantace nového typu kompozitního materiálu, polyesterové síťky potažené tenkou vrstvou polyuretanu, v experimentu na laboratorním potkanu. Materiál a metoda: Experiment byl proveden na 21 laboratorních potkanech. Laboratorní zvířata byla rozdělena do 3 skupin po 7 jedincích. U první skupiny byla provedena kontrolní laparotomie 7. den, u druhé skupiny 14. den a u třetí skupiny 28. den po intraperitoneální implantaci kompozitní síťky. Byla posouzena tvorba adhezí s břišními útrobami a histologicky byly vyšetřeny vzorky tkání s implantovanou síťkou. Výsledky: Makroporózní polyesterová vrstva síťky podporovala časnou a mohutnou vazivovou proliferaci s dobrou adhezivitou k břišní stěně. Na druhé straně mikroporózní polyuretanová vrstva vedla k vytvoření vazivové kapsy. Při kontrolní laparotomii byly u většiny laboratorních potkanů ve všech skupinách nalezeny rozsáhlejší adheze omenta k vazivové vrstvě pokrývající polyuretanovou stranu implantované síťky. Závěr: Lze předpokládat, že ochranná polyuretanová vrstva nevylučuje riziko tvorby adhezí u laboratorního potkana.
Introduction: Polyester and polypropylene are currently the most frequently materials for repair of abdominal wall hernias. Most of the mesh materials used intraperitoneally in repair of hernias lead to considerable adhesion formation, as well as the resultant bowel obstruction and intestinal fistula formation. Some newer composite products can reduce risk of adhesion formation. The aim of this experimental study is testing properties of patch, composite structure, characterised by the association of a non-woven textile structure made from polyester multifilaments, and a fine coat of polyurethane on one side, placed intraperitoneally in rat. Materials and methods: The experiment was carried out with 21 laboratory rats. Laboratory animals were divided into 3 groups – 7 animals in a group. In the first group the check-up laparotomy was realized the 7th day, in the second group the 14th day and in the third group the 28th day after the intraperitoneal implantation of a composite mesh. All animals were sacrificed and adhesion scoring and histological evaluation of tissue specimens with implanted mesh were done. Results:Amacroporous polyester mesh component supported an early and huge fibrous proliferation with a good adhesion onto the abdomen wall. On the other hand, a microporous polyurethane layer led to the creation of a fibrous pocket. During the check-up laparotomy, the larger adhesion of omentum to the fibrous layer, covering the polyurethane side of implanted mesh, were located in most laboratory rats – in all the groups. Conclusion: We can presume that the protective polyurethane layer does not eliminate risk of adhesion formation in rat.
- MeSH
- adheze tkání MeSH
- chirurgické síťky využití MeSH
- experimentální implantáty trendy MeSH
- hernie MeSH
- krysa rodu rattus MeSH
- modely u zvířat MeSH
- operace kýly MeSH
- polyestery terapeutické užití MeSH
- polyurethany terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- přehledy MeSH
- srovnávací studie MeSH
- MeSH
- chirurgické vybavení MeSH
- hernie komplikace MeSH
- lidé MeSH
- nemoc MeSH
- operace kýly MeSH
- polyestery terapeutické užití MeSH
- Check Tag
- lidé MeSH
The influence of biofilm formation as the mode of microorganism growth on degradation of synthetic polymers represents an important research topic. This study focuses on the effect of biofilm developed by Bacillus subtilis (BS) cultivated submerged under various nutrition conditions on biodeterioration of poly(ε-caprolactone) film. Polymer in the film form (thickness 0.7 mm) was incubated for 21 days either continuously or by regularly renewed system. The scission of polyester chain bonds took place in all biotic media and was enhanced by biofilm formation in nutrient-rich media.
Compartmentalization was likely essential for primitive chemical systems during the emergence of life, both for preventing leakage of important components, i.e., genetic materials, and for enhancing chemical reactions. Although life as we know it uses lipid bilayer-based compartments, the diversity of prebiotic chemistry may have enabled primitive living systems to start from other types of boundary systems. Here, we demonstrate membraneless compartmentalization based on prebiotically available organic compounds, α-hydroxy acids (αHAs), which are generally coproduced along with α-amino acids in prebiotic settings. Facile polymerization of αHAs provides a model pathway for the assembly of combinatorially diverse primitive compartments on early Earth. We characterized membraneless microdroplets generated from homo- and heteropolyesters synthesized from drying solutions of αHAs endowed with various side chains. These compartments can preferentially and differentially segregate and compartmentalize fluorescent dyes and fluorescently tagged RNA, providing readily available compartments that could have facilitated chemical evolution by protecting, exchanging, and encapsulating primitive components. Protein function within and RNA function in the presence of certain droplets is also preserved, suggesting the potential relevance of such droplets to various origins of life models. As a lipid amphiphile can also assemble around certain droplets, this further shows the droplets' potential compatibility with and scaffolding ability for nascent biomolecular systems that could have coexisted in complex chemical systems. These model compartments could have been more accessible in a "messy" prebiotic environment, enabling the localization of a variety of protometabolic and replication processes that could be subjected to further chemical evolution before the advent of the Last Universal Common Ancestor.
- MeSH
- fluorescenční barviva chemie MeSH
- FRAP MeSH
- koncentrace vodíkových iontů MeSH
- kyseliny karboxylové chemie MeSH
- membrány umělé * MeSH
- polyestery chemická syntéza chemie MeSH
- původ života * MeSH
- RNA chemie MeSH
- velikost částic MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
