This research introduces a novel approach by incorporating various types of gelatins, including bovine, porcine, and fish skin, into polycaprolactone and poly (lactic-co-glycolic acid) using a solvent casting method. The films are evaluated for morphology, mechanical properties, thermal stability, biodegradability, hemocompatibility, cell adhesion, proliferation, and cytotoxicity. The results show that the incorporation of gelatins into the films alters their mechanical properties, with a decrease in tensile strength but an increase in elongation at break. This indicates that the films become more flexible with the addition of gelatin. Gelatin incorporation has a limited effect on the thermal stability of the films. The composites with the gelatin show higher biodegradability with the highest weight loss in the case of fish gelatin. The films exhibit high hemocompatibility with minimal hemolysis observed. The gelatin has a dynamic effect on cell behavior and promotes long-term cell proliferation. In addition, all composite films reveal exceptionally low levels of cytotoxicity. The combination of the evaluated parameters shows the appropriate level of biocompatibility for gelatin-based samples. These findings provide valuable insights for future studies involving gelatin incorporation in tissue engineering applications.
- Publikační typ
- časopisecké články MeSH
126 stran ; 21 cm
Modelové testy z oblasti chemie pro rok 2019. Určeno pro uchazeče o studium všeobecného a zubního lékařství.
- MeSH
- chemie výchova MeSH
- přijímací zkouška na vysokou školu MeSH
- studium lékařství MeSH
- univerzity MeSH
- Publikační typ
- učebnice MeSH
- Konspekt
- Chemie. Mineralogické vědy
- Učební osnovy. Vyučovací předměty. Učebnice
- NLK Obory
- chemie, klinická chemie
- NLK Publikační typ
- testy
Currently, titanium endosseous implants represent the standard in dental implantology. To improve their mechanical properties, biocompatibility and osseointegration, the concept of bulk nanostructured titanium with variously textured surface is being developed. Different animal species, mostly pigs, minipigs and rabbits, are used for the osseointegration assessment. The selection of implantation site in the target bone is also important, because various types of bones have different ratio between the compact and the trabecular bone tissue. After finishing the in vivo experiment, the implant position and orientation is verified by X-ray imaging. The part of the bone with the implant is surgically removed, cut into tissue blocks, and histologically processed using technique of undemineralized ground sections. This includes embedding the samples into resin followed by sawing, grinding, and polishing of transparent histological sections. A subsequent staining provides information on the formation and mineralization of the bone matrix in close proximity of the implant. Osseointegration is evaluated using a bone-implant contact (BIC) expressed as the ratio of the implant length in contact with bone tissue and total length of the implant. Additional information about the newly formed bone in regions surrounding the implant may be also provided by a double tetracycline test. According to our own experiments, this methodology is simple to perform, highly reproducible, and gives consistent results.
- MeSH
- lidé MeSH
- nanostruktury MeSH
- titan MeSH
- zubní implantáty * MeSH
- zubní materiály MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Publikační typ
- abstrakt z konference MeSH
Studie se zaměřuje na hodnocení účinku opakované expozice HBO na mitochondriální respiraci lidských fetálních plicních fibroblastů (HFL1). Mitochondriální spotřeba kyslíku byla hodnocena metodou high-resolution respirometry (HRR), životaschopnost buněk hodnocena PrestoBlue®, morfologie analyzovaná rutinní fluorescenční mikroskopií a fázovým kontrastem a byla zhodnocena aktivita superoxid dismutázy (SOD) a citrát syntázy (CS). Buňky byly vystaveny HBO (3ATA) 2 hodiny denně po dobu 5 po sobě jdoucích dní. Den po poslední HBO expozici vykazovaly buňky podstatně menší plochu a obvod, sníženou životaschopnost a zvýšenou aktivitu SOD. Nebyly zjištěny žádné změny v aktivitě CS ani v kvalitě mitochondriální sítě. HRR odhalila sníženou mitochondriální spotřebu kyslíku, která se projevila snížením aktivity komplexu II a sníženou spotřebou kyslíku při oxidací mastných kyselin. Naše zjištění dokládají, že v podmínkách napodobujících intermitentní expozici HBO, trpí plicní fibroblasty zhoršenou mitochondriální respirací spojenou s komplexem II a poruchou buněčného růstu i při zvýšené antioxidační obraně. Mechanismus této HBO-indukované mitochondriální dysfunkce je nutné hlouběji prozkoumat.
Study aims to evaluate effects of repeated exposure to HBO on mitochondrial respiration assessed by high-resolution respirometry (HRR), cell viability estimated by PrestoBlue® reaction, morphology analyzed by routine phase contrast and fluorescent microscopy, and superoxide dismutase (SOD) and citrate synthase (CS) activities using human lung fibroblasts. The cells were exposed to HBO (3 ATA) for 2 hours per day for 5 consecutive days. One day after the last exposure, HBO cells displayed significantly smaller area and perimeter, compromised viability and elevated SOD activity. No changes were detected in CS activity or quality of mitochondrial network. HRR revealed impaired mitochondrial oxygen consumption manifested by increased leak respiration, decreased activity of complex II and compromised ATP-related oxygen consumption when fatty acids were oxidized. Our findings document that in conditions mimicking chronic intermittent exposure to HBO, lung fibroblasts suffer from compromised mitochondrial respiration linked to complex II and impaired cellular growth in spite of increased antioxidant defense. Underlying mechanism of this HBO-induced mitochondrial dysfunction should be further explored.
- Klíčová slova
- respirometrie,
- MeSH
- buněčné dýchání MeSH
- fibroblasty * enzymologie metabolismus MeSH
- fluorescenční mikroskopie MeSH
- hyperbarická oxygenace * škodlivé účinky MeSH
- hyperoxie MeSH
- lidé MeSH
- mitochondrie MeSH
- plíce anatomie a histologie MeSH
- plod MeSH
- superoxiddismutasa MeSH
- techniky in vitro MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Hyperbaric oxygen (HBO) therapy, i.e. breathing pure oxygen under increased environmental pressures serves as a treatment for diverse medical conditions. However, elevated oxygen concentration can be detrimental to central nervous system or lungs. Our study aimed to evaluate the effects of repeated exposure to HBO on mitochondrial respiration assessed by high-resolution respirometry (HRR), cell viability estimated by PrestoBlue® reaction, morphology analyzed by routine phase contrast and fluorescent microscopy, and superoxide dismutase (SOD) and citrate synthase (CS) activities using human lung fibroblasts. The cells were exposed to HBO for 2 h per day for 5 consecutive days. One day after the last exposure, HBO cells displayed significantly smaller area and perimeter, compromised viability and elevated SOD activity. No changes were detected in CS activity or quality of mitochondrial network. HRR revealed impaired mitochondrial oxygen consumption manifested by increased leak respiration, decreased activity of complex II and compromised ATP-related oxygen consumption when fatty acids were oxidized. Our findings document that in conditions mimicking chronic intermittent exposure to HBO, lung fibroblasts suffer from compromised mitochondrial respiration linked to complex II and impaired cellular growth in spite of increased antioxidant defense. Underlying mechanism of this HBO-induced mitochondrial dysfunction should be further explored.
- MeSH
- buněčné dýchání fyziologie MeSH
- buněčné linie MeSH
- fibroblasty metabolismus MeSH
- hyperbarická oxygenace škodlivé účinky MeSH
- lidé MeSH
- mitochondrie fyziologie MeSH
- oxidační stres fyziologie MeSH
- plíce cytologie metabolismus MeSH
- spotřeba kyslíku fyziologie MeSH
- viabilita buněk fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Emerging evidence indicates that polychlorinated biphenyls (PCBs) are involved in the development of diabetes mellitus in the obese. The purpose of this study was to determine mechanisms by which PCB 153 (2,2´,4,4´,5,5´-hexachloro-biphenyl) could influence diet-induced obesity and insulin resistance during adipogenesis. Lineage of h-ADMSCs was differentiated either as control (differentiation medium only), or with lipid vehicle modeling high fat nutrition (NuTRIflex) or lipid free vehicle (dimethylsulfoxide) for 28 days with or without PCB 153 daily co-exposure (in three concentrations 0.1, 1, and 10 microM). Gene expression analyses were performed using RT-qPCR at days 4, 10, 21, 24, 28; protein levels Akt and phosphorylated Akt (Phospho-Akt) by Western blot at days 4, and 21. PCB 153 treatment of h-ADMSCs only in lipid vehicle was associated with down regulation of key master genes of adipogenesis: PPARgamma, SREBP-1, PPARGC1B, and PLIN2 during the whole process of differentiation; and with increased Akt and decreased Phospho-Akt protein level at day 21. We have shown that PCB 153, in concentration 0.1 microM, has a potential in lipid rich environment to modulate differentiation of adipocytes. Because European and U.S. adults have been exposed to PCB 153, this particular nutrient-toxicant interaction potentially impacts human obesity and insulin sensitivity.
- MeSH
- buněčná diferenciace účinky léků fyziologie MeSH
- inzulinová rezistence fyziologie MeSH
- kultivované buňky MeSH
- lidé MeSH
- obezita chemicky indukované metabolismus MeSH
- polychlorované bifenyly toxicita MeSH
- tukové buňky účinky léků metabolismus MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Evidence indicating, that persistent organic pollutants are involved in the development of obesity, has emerged. The aim of this study was to reveal whether an environmental bioaccumulative human adipose tissue contaminant, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), affects adipocyte differentiation. Our study was conducted on an in vitro adipogenic model of human adipose derived mesenchymal stem cells (hADMSC). The adipose cultures were exposed to DDE (concentrations: 0.1 μM, 1 μM, and 10 μM) for 28 consecutive days, from the beginning of the experiment until full differentiation. DDE was administered in lipid vehicle (NuTRIflex). Samples for gene expression analysis by RT real-time PCR were collected on days 0, 4, 10, 21 and 28 during the course of differentiation. Differentiating adipocytes cultivated in lipid-rich medium (NuTRIflex) increased the expression of perilipin 2 (PLIN2). However, the addition of DDE suppressed this effect (p < 0.03). Our results may suggest that upregulation of PLIN2, caused by exposure to lipids during the differentiation of adipocytes, is reduced in the presence of DDE. This effect of DDE warrants future attention, because of the important role of PLIN2 in formation and stabilization of lipid droplets, as the impairment of their function could be linked to the worldwide obesity epidemic.
- Klíčová slova
- perilipin-2,
- MeSH
- buněčná diferenciace účinky léků MeSH
- dichlordifenyldichlorethylen * MeSH
- kultivované buňky MeSH
- látky znečišťující životní prostředí metabolismus MeSH
- lipidová tělíska metabolismus MeSH
- membránové proteiny * genetika MeSH
- mezenchymální kmenové buňky MeSH
- neparametrická statistika MeSH
- pesticidy MeSH
- tukové buňky * metabolismus účinky léků MeSH
- upregulace MeSH
- Publikační typ
- práce podpořená grantem MeSH
Mitochondria play a key role in energy metabolism in many tissues, including cardiac and skeletal muscle, brain, liver, and adipose tissue. Three types of adipose depots can be identified in mammals, commonly classified according to their colour appearance: the white (WAT), the brown (BAT), and the beige/brite/brown-like (bAT) adipose tissues. WAT is mainly involved in the storage and mobilization of energy and BAT is predominantly responsible for nonshivering thermogenesis. Recent data suggest that adipocyte mitochondria might play an important role in the development of obesity through defects in mitochondrial lipogenesis and lipolysis, regulation of adipocyte differentiation, apoptosis, production of oxygen radicals, efficiency of oxidative phosphorylation, and regulation of conversion of white adipocytes into brown-like adipocytes. This review summarizes the main characteristics of each adipose tissue subtype and describes morphological and functional modifications focusing on mitochondria and their activity in healthy and unhealthy adipocytes.
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
