Litvinec, A*
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Stroke is despite of progressive improvements in treatment and reperfusion strategies one of the most devastating human pathology. However, as quality of acute health care improves and more people survive ischemic attack, healthcare specialists have to solve new challenges to preserve reasonable quality of life to these patients. Thus, novel approaches which prevents comorbidities of stroke and improve quality of life of stroke survivors in general has to be developed and experimentally tested. The aim of the present paper was to establish reliable rat model of middle cerebral occlusion and set of methods allowing selection of animals suitable for long-term experiments. We have compared mortality rates, cerebral blood flow and extension of ischemic lesion induced by intraluminal filament in three widely used outbred rat strains. We have additionally used an animal 18F-DG PET scans to verify its reliability in noninvasive detection of ischemic infarct in acute period (24 h after MCAO) for selecting animals eligible for long survival experiments. Our data clearly indicates that high variability between rat strains might negatively influence stroke induction by intraluminal thread occlusion of middle cerebral artery. Most reliable outbred rat strain in our hands was Sprague-Dawley where maximal reduction of cerebral blood flow and extensive ischemic lesion was observed. Contrary, Wistar rats exhibited higher mortality and Long-Evans rats significantly smaller or no ischemic region in comparison to Sprague-Dawley. Additionally, we have confirmed a positron emission tomography with 18F-fluorodeoxyglucose as suitable method to assess extension of ischemic region in acute period after the experimental arterial occlusion in rats.
- MeSH
- druhová specificita MeSH
- infarkt arteria cerebri media diagnostické zobrazování genetika patofyziologie MeSH
- krysa rodu rattus MeSH
- mozkový krevní oběh fyziologie MeSH
- potkani Long-Evans MeSH
- potkani Sprague-Dawley MeSH
- potkani Wistar MeSH
- pozitronová emisní tomografie metody MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
This study was carried out to investigate how pinworm infection in rats affects nutrient digestibility in the hosts. Twenty-four male outbred Wistar rats were randomly divided into two groups of 12 rats each. The rats from the first group (GI) were kept in cages with bedding containing pinworm eggs, and the second (control) group (GII) were kept in a separate room in clean, uncontaminated filter-top cages. The animals were put into individual metabolic cages later. Metabolic trials lasted five days and records of animal weight, food ingestion, and faecal weight were taken daily. Based on laboratory analysis of the feed and faecal nutrient content, digestibility values were determined. On day 15 of the experiment, the animals were euthanized. Although Syphacia muris were found in all rats from the GI group, animals exhibited no clinical signs. In our experiment, S. muris infection reduced the overall digestibility of all measured nutrients (P < 0.01). The most significant differences in digestibility were observed in the case of crude fibre and mineral matter (P < 0.01).
- MeSH
- energetický metabolismus MeSH
- fyziologie výživy zvířat * MeSH
- krysa rodu rattus * MeSH
- laboratorní zvířata MeSH
- náhodné rozdělení MeSH
- nemoci hlodavců parazitologie MeSH
- oxyuriáza parazitologie MeSH
- Oxyuroidea fyziologie MeSH
- potkani Wistar MeSH
- stravovací zvyklosti MeSH
- trávení * MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus * MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The study involved the electrospinning of the copolymer poly(L-lactide-co-ε-caprolactone) (PLCL) into tubular grafts. The subsequent material characterization, including micro-computed tomography analysis, revealed a level of porosity of around 70%, with pore sizes of 9.34 ± 0.19 μm and fiber diameters of 5.58 ± 0.10 μm. Unlike fibrous polycaprolactone, the electrospun PLCL copolymer promoted fibroblast and endothelial cell adhesion and proliferation in vitro. Moreover, the regeneration of the vessel wall was detected following implantation and, after six months, the endothelialization of the lumen and the infiltration of arranged smooth muscle cells producing collagen was observed. However, the degradation rate was found to be accelerated in the rabbit animal model. The study was conducted under conditions that reflected the clinical requirements-the prostheses were sutured in the end-to-side fashion and the long-term end point of prosthesis healing was assessed. The regeneration of the vessel wall in terms of endothelialization, smooth cell infiltration and the presence of collagen fibers was observed after six months in vivo. A part of the grafts failed due to the rapid degradation rate of the PLCL copolymer.
- MeSH
- aorta patologie MeSH
- arteriae carotides patologie MeSH
- buněčná adheze MeSH
- buňky 3T3 MeSH
- cévní protézy * MeSH
- endoteliální buňky pupečníkové žíly (lidské) MeSH
- endoteliální buňky MeSH
- fibroblasty cytologie MeSH
- kolagen metabolismus MeSH
- králíci MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- myocyty hladké svaloviny cytologie MeSH
- myši MeSH
- polyestery chemie MeSH
- polymery chemie MeSH
- poréznost MeSH
- prasata MeSH
- psi MeSH
- regenerace MeSH
- rentgenová mikrotomografie MeSH
- tkáňové inženýrství metody MeSH
- tkáňové podpůrné struktury MeSH
- transplantace cév * MeSH
- zobrazování trojrozměrné MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- myši MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Hydrogels are suitable for osteochondral defect regeneration as they mimic the viscoelastic environment of cartilage. However, their biomechanical properties are not sufficient to withstand high mechanical forces. Therefore, we have prepared electrospun poly-ε-caprolactone-chitosan (PCL-chit) and poly(ethylene oxide)-chitosan (PEO-chit) nanofibers, and FTIR analysis confirmed successful blending of chitosan with other polymers. The biocompatibility of PCL-chit and PEO-chit scaffolds was tested; fibrochondrocytes and chondrocytes seeded on PCL-chit showed superior metabolic activity. The PCL-chit nanofibers were cryogenically grinded into microparticles (mean size of about 500 µm) and further modified by polyethylene glycol-biotin in order to bind the anti-CD44 antibody, a glycoprotein interacting with hyaluronic acid (PCL-chit-PEGb-antiCD44). The PCL-chit or PCL-chit-PEGb-antiCD44 microparticles were mixed with a composite gel (collagen/fibrin/platelet rich plasma) to improve its biomechanical properties. The storage modulus was higher in the composite gel with microparticles compared to fibrin. The Eloss of the composite gel and fibrin was higher than that of the composite gel with microparticles. The composite gel either with or without microparticles was further tested in vivo in a model of osteochondral defects in rabbits. PCL-chit-PEGb-antiCD44 significantly enhanced osteogenic regeneration, mainly by desmogenous ossification, but decreased chondrogenic differentiation in the defects. PCL-chit-PEGb showed a more homogeneous distribution of hyaline cartilage and enhanced hyaline cartilage differentiation.
- Publikační typ
- časopisecké články MeSH
Aim: This study evaluates the effect of electrospun dressings in critical sized full-thickness skin defects in rabbits. Materials & methods: Electrospun poly-ε-caprolactone (PCL) and polyvinyl alcohol (PVA) nanofibers were tested in vitro and in vivo. Results: The PCL scaffold supported the proliferation of mesenchymal stem cells, fibroblasts and keratinocytes. The PVA scaffold showed significant swelling, high elongation capacity, limited protein adsorption and stimulation of cells. Nanofibrous dressings improved wound healing compared with the control group in vivo. A change of the PCL dressing every 7 days resulted in a decreased epithelial thickness and type I collagen level in the adhesive group, indicating peeling off of the newly formed tissue. In the PVA dressings, the exchange did not affect healing. Conclusion: The results demonstrate the importance of proper dressing exchange.
- MeSH
- buňky 3T3 MeSH
- hojení ran účinky léků MeSH
- králíci MeSH
- kůže * zranění metabolismus patologie MeSH
- myši MeSH
- nanovlákna chemie MeSH
- obvazy * MeSH
- polyestery * chemie farmakologie MeSH
- polyvinylalkohol chemie farmakologie MeSH
- prasata MeSH
- tkáňová adheziva * chemie farmakologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The present study investigates the effect of an oxidized nanocrystalline diamond (O-NCD) coating functionalized with bone morphogenetic protein 7 (BMP-7) on human osteoblast maturation and extracellular matrix mineralization in vitro and on new bone formation in vivo. The chemical structure and the morphology of the NCD coating and the adhesion, thickness and morphology of the superimposed BMP-7 layer have also been assessed. The material analysis proved synthesis of a conformal diamond coating with a fine nanostructured morphology on the Ti6Al4V samples. The homogeneous nanostructured layer of BMP-7 on the NCD coating created by a physisorption method was confirmed by AFM. The osteogenic maturation of hFOB 1.19 cells in vitro was only slightly enhanced by the O-NCD coating alone without any increase in the mineralization of the matrix. Functionalization of the coating with BMP-7 resulted in more pronounced cell osteogenic maturation and increased extracellular matrix mineralization. Similar results were obtained in vivo from micro-CT and histological analyses of rabbit distal femurs with screws implanted for 4 or 12 weeks. While the O-NCD-coated implants alone promoted greater thickness of newly-formed bone in direct contact with the implant surface than the bare material, a further increase was induced by BMP-7. It can be therefore concluded that O-NCD coating functionalized with BMP-7 is a promising surface modification of metallic bone implants in order to improve their osseointegration.
- MeSH
- biokompatibilní potahované materiály chemie farmakologie MeSH
- diamant chemie MeSH
- extracelulární matrix MeSH
- kostní morfogenetický protein 7 * farmakologie MeSH
- králíci MeSH
- osteointegrace * MeSH
- slitiny MeSH
- titan MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- aktivní transport MeSH
- astrocyty MeSH
- biologický transport MeSH
- endotel MeSH
- epilepsie etiologie MeSH
- hematoencefalická bariéra * anatomie a histologie fyziologie patologie účinky léků MeSH
- lékové transportní systémy MeSH
- lidé MeSH
- mikroglie MeSH
- mozek anatomie a histologie fyziologie MeSH
- neurony MeSH
- pericyty MeSH
- zánět imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Incisional hernia affects up to 20% of patients after abdominal surgery. Unlike other types of hernia, its prognosis is poor, and patients suffer from recurrence within 10 years of the operation. Currently used hernia-repair meshes do not guarantee success, but only extend the recurrence-free period by about 5 years. Most of them are nonresorbable, and these implants can lead to many complications that are in some cases life-threatening. Electrospun nanofibers of various polymers have been used as tissue scaffolds and have been explored extensively in the last decade, due to their low cost and good biocompatibility. Their architecture mimics the natural extracellular matrix. We tested a biodegradable polyester poly-ε-caprolactone in the form of nanofibers as a scaffold for fascia healing in an abdominal closure-reinforcement model for prevention of incisional hernia formation. Both in vitro tests and an experiment on a rabbit model showed promising results.
- MeSH
- biomechanika MeSH
- břicho chirurgie MeSH
- buňky 3T3 MeSH
- chirurgické síťky MeSH
- hernie prevence a kontrola MeSH
- histocytochemie MeSH
- hojení ran účinky léků MeSH
- králíci MeSH
- mezibuněčné signální peptidy a proteiny chemie farmakologie terapeutické užití MeSH
- myši MeSH
- nanovlákna chemie terapeutické užití MeSH
- polyestery chemie terapeutické užití MeSH
- polypropyleny chemie terapeutické užití MeSH
- pooperační komplikace prevence a kontrola MeSH
- řízená tkáňová regenerace MeSH
- techniky uzavření břišních poranění přístrojové vybavení MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
