The chicken Tva cell surface protein, a member of the low-density lipoprotein receptor family, has been identified as an entry receptor for avian leukosis virus of classic subgroup A and newly emerging subgroup K. Because both viruses represent an important concern for the poultry industry, we introduced a frame-shifting deletion into the chicken tva locus with the aim of knocking-out Tva expression and creating a virus-resistant chicken line. The tva knock-out was prepared by CRISPR/Cas9 gene editing in chicken primordial germ cells and orthotopic transplantation of edited cells into the testes of sterilized recipient roosters. The resulting tva -/- chickens tested fully resistant to avian leukosis virus subgroups A and K, both in in vitro and in vivo assays, in contrast to their susceptible tva +/+ and tva +/- siblings. We also found a specific disorder of the cobalamin/vitamin B12 metabolism in the tva knock-out chickens, which is in accordance with the recently recognized physiological function of Tva as a receptor for cobalamin in complex with transcobalamin transporter. Last but not least, we bring a new example of the de novo resistance created by CRISPR/Cas9 editing of pathogen dependence genes in farm animals and, furthermore, a new example of gene editing in chicken.
- MeSH
- editace genu MeSH
- genový knockout MeSH
- kur domácí virologie MeSH
- kuřecí embryo MeSH
- kyselina methylmalonová krev MeSH
- posunová mutace MeSH
- ptačí proteiny genetika fyziologie MeSH
- virové receptory genetika fyziologie MeSH
- virus ptačí leukózy klasifikace fyziologie MeSH
- vitamin B 12 metabolismus MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: We had a case in which three consecutive pregnancies resulted in birth of three children with an orofacial cleft. Their mother suffered from bronchial asthma and was treated using symbicort (corticosteroid budesonide plus bronchodilator formoterol) during her pregnancies. A hypothesis was assessed: these anti-asthmatics can induce an orofacial cleft in experimental model. MATERIALS AND METHODS: A single administration of one of five increasing doses (including therapeutically used ones) of Symbicort, budesonide or formoterol was injected into the amnion of a chick embryo on day 4 or 5 of incubation. The teratogenic/lethal effects of the anti-asthmatics were assessed on a total of 600 embryos. RESULTS: For budesonide, the teratogenic/lethal effect started at a dose 0.003 μg per embryo, for formoterol at 0.3 μg and for Symbicort 0.03 μg. Orofacial clefts and gastroschisis after exposure were found for all three anti-asthmatics. Heart septum defects occurred after exposure to formoterol. CONCLUSION: The present results support those clinical/epidemiological studies pointing out that anti-asthmatics have the potential to induce orofacial clefts, gastroschisis and heart malformations during prenatal development in human.
- MeSH
- antiastmatika * MeSH
- aplikace inhalační MeSH
- budesonid škodlivé účinky MeSH
- dítě MeSH
- dvojitá slepá metoda MeSH
- ethanolaminy škodlivé účinky MeSH
- formoterol fumarát škodlivé účinky MeSH
- gastroschiza * chemicky indukované MeSH
- kombinace léků budesonid a formoterol MeSH
- kuřecí embryo MeSH
- lidé MeSH
- rozštěp patra * chemicky indukované MeSH
- rozštěp rtu * chemicky indukované MeSH
- srdeční septum MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- kuřecí embryo MeSH
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND/AIM: Although it has been accepted that the tandem repeat galectin-8 (Gal-8) is linked to angiogenesis, the underlying mechanisms in endothelial cells has remained poorly understood. In this study we aimed to investigate the effect of Gal-8 on selected biological processes linked to angiogenesis in in vitro and in vivo models. MATERIALS AND METHODS: In detail, we assessed how exogenously added human recombinant Gal-8 (with or without vascular endothelial growth factor - VEGF) affects selected steps involved in vessel formation in human umbilical vein endothelial cells (HUVECs) as well as using the chick chorioallantoic membrane (CAM) assay. Gene expression profiling of HUVECs was performed to extend the scope of our investigation. RESULTS: Our findings demonstrate that Gal-8 in combination with VEGF enhanced cell proliferation and migration, two cellular events linked to angiogenesis. However, Gal-8 alone did not exhibit any significant effects on cell proliferation or on cell migration. The molecular analysis revealed that Gal-8 in the presence of VEGF influenced cytokine-cytokine receptor interactions, HIF-1 and PI3K/AKT signaling pathways. Gal-8 alone also targeted cytokine-cytokine receptor interactions, but with a different expression profile as well as a modulated focal adhesion and TNF signaling. CONCLUSION: Gal-8 promotes a pro-angiogenic phenotype possibly in a synergistic manner with VEGF.
- MeSH
- chorioalantoická membrána krevní zásobení účinky léků metabolismus MeSH
- endoteliální buňky pupečníkové žíly (lidské) cytologie účinky léků metabolismus MeSH
- fyziologická neovaskularizace účinky léků MeSH
- galektiny metabolismus farmakologie MeSH
- kuřecí embryo MeSH
- lidé MeSH
- pohyb buněk účinky léků MeSH
- stanovení celkové genové exprese MeSH
- techniky in vitro MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Optical mapping is a fluorescence-based physiological method to image spreading of action potential in excitable tissues, such as the heart and central nervous system. Because of the requirements for high speed imaging in low light conditions, highly sensitive high-speed cameras together with an optical system with maximum photon efficiency are required. While the optimization of these two components is relatively straightforward, the choice of the perfect light source is less simple; depending on the other (usually fixed) components, various parameters may acquire different weight in decision-making process. Here we describe the rationale for building an optical mapping setup and consider the relative advantages and disadvantages of three different commonly available light sources: mercury vapor lamp (HBO), xenon lamp (XBO), and light emitting diode (LED). Using the same optical system (fluorescence macroscope) and high-speed camera (Ultima L), we have tested each of the sources for its ability to provide bright and even illumination of the field of view and measured its temporal fluctuations in intensity. Then we used each in the actual optical mapping experiment using isolated, perfused adult mouse heart or chick embryonic heart to determine the actual signal to noise ratio at various acquisition rates. While the LED sources have undergone significant improvements in the recent past, the other alternatives may still surpass them in some parameters, so they may not be the automatic number one choice for every application.
- MeSH
- akční potenciály MeSH
- fluorescenční barviva chemie MeSH
- kuřecí embryo MeSH
- myši MeSH
- srdce fyziologie MeSH
- světlo MeSH
- vápník analýza metabolismus MeSH
- zobrazování pomocí barviva citlivého na potenciál metody normy MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Cryptosporidium is a genus of apicomplexan parasites that inhabit the respiratory and gastrointestinal tracts of vertebrates. Research of these parasites is limited by a lack of model hosts. This study aimed to determine the extent to which infection at the embryo stage can enhance the propagation of Cryptosporidium oocysts in chickens. Nine-day-old chicken embryos and one-day-old chickens were experimentally infected with different doses of Cryptosporidium baileyi and Cryptosporidium parvum oocysts. Post hatching, all chickens had demonstrable infections, and the infection dose had no effect on the course of infection. Chickens infected as embryos shed oocysts immediately after hatching and shed significantly more oocysts over the course of the infection than chickens infected as one-day-olds. In chickens infected as embryos, C. baileyi was found in all organs except the brain whereas, C. parvum was only found in the gastrointestinal tract and trachea. In chickens infected as one-day-olds, C. baileyi was only found in the gastrointestinal tract and trachea. Chickens infected as embryos with C. baileyi died within 16 days of hatching. All other chickens cleared the infection. Infection of chickens as embryos could be used as an effective and simple model for the propagation of C. baileyi and C. parvum.
The aim of the study was toxicological testing of an innovative and efficient antimicrobial agent based on photoactive phthalocyanine (Pc) derivative. A promising Aluminium phthalocyanine (AlPc) with efficient and stable antimicrobial effects was subjected to a battery of toxicological tests to avoid local and systemic toxicity hazard. In compliance with the current European legislation restricting the use of experimental animals, the methods comprised exclusively in vitro procedures based on cellular and tissue models of human origin or mimicking human tissues. The battery of toxicological tests to identify local toxicity included skin corrosion/irritation, eye irritation, and phototoxicity. The basic systemic toxicity tests included acute toxicity, skin sensitization, genotoxicity, and endocrine disruption. The results showed that AlPc induced skin and eye irritation, exhibited borderline sensitization potential and mutagenic potential in one test strain of the Ames test, which was not confirmed in the chromosome aberration test. The AlPc was found to be phototoxic. The results from the cytotoxicity test designed for acute oral toxicity estimation were not conclusive, the acute toxicity potential has to be determined by conventional tests in vivo. Regarding endocrine disruption, no agonistic activity of the AlPc on human estrogen receptor α, nor human androgen receptor was observed. The skin penetration/absorption test revealed that the AlPc has not penetrated into the dermis and receptor fluid, confirming no risk of systemic exposure via the bloodstream.
- MeSH
- alfa receptor estrogenů metabolismus MeSH
- androgenní receptory metabolismus MeSH
- antiinfekční látky farmakokinetika toxicita MeSH
- chorioalantoická membrána krevní zásobení účinky léků MeSH
- dráždivé látky farmakokinetika toxicita MeSH
- fotochemické procesy MeSH
- indoly farmakokinetika toxicita MeSH
- kožní absorpce MeSH
- kultivované buňky MeSH
- kuřecí embryo MeSH
- kůže účinky léků metabolismus MeSH
- lidé MeSH
- lymfocyty účinky léků MeSH
- myši inbrední BALB C MeSH
- oči účinky léků MeSH
- poškození DNA MeSH
- prasata MeSH
- testy toxicity MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The globally increasing incidence of cancer, including melanoma, requires novel therapeutic strategies. Development of successful novel drugs is based on clear identification of the target mechanisms responsible for the disease progression. The specific cancer microenvironment represents a critically important aspect of cancer biology, which cannot be properly studied in simplistic cell culture conditions. Among other traditional options, the study of melanoma cell growth on the chicken chorioallantoic membrane offers several significant advantages. This model offers increased complexity compared to usual in silico culture models and still remains financially affordable. Using this model, we studied the growth of three established human melanoma cell lines: A2058, BLM, G361. The combination of histology, immunohistochemistry with the application of human-specific antibodies, intravascular injection of contrast material such as filtered Indian ink, Mercox solution and phosphotungstic acid, and X-ray micro-CT and live-cell monitoring was employed. Melanoma cells spread well on the chicken chorioallantoic membrane. However, invasion into the stroma of the chorioallantoic membrane and the limb primordium graft was rare. The melanoma cells also significantly influenced the architecture of the blood vessel network, resulting in the orientation of the vessels to the site of the tumour cell inoculation. The system of melanoma cell culture on the chorioallantoic membrane is suitable for the study of melanoma cell growth, particularly of rearrangement of the host vascular pattern after cancer cell implantation. The system also has promising potential for further development.
- MeSH
- biologické modely * MeSH
- chorioalantoická membrána metabolismus patologie MeSH
- imunohistochemie MeSH
- kur domácí MeSH
- kuřecí embryo MeSH
- lidé MeSH
- melanom experimentální metabolismus patologie MeSH
- nádorové buňky kultivované MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Hypothermic incubation of chicken eggs leads to smaller embryos with enlarged hearts, originally described as hypertrophic. Over the years, however, accumulated evidence suggested that hyperplasia, rather than hypertrophy, is the predominant mechanism of cardiac growth during the prenatal period. We have thus set to re-evaluate the hypothermia model to precise the exact cellular mechanism behind cardiac enlargement. Fertilized chicken eggs were incubated at either 37.5 °C (normothermia) or 33.5 °C from embryonic day (ED) 13 onward (hypothermia). Sampling was performed at ED17, at which point wet embryo and heart weight were recorded, and the hearts were submitted to histological examination. In agreement with previous results, the hypothermic embryos were 29% smaller and had hearts 18% larger, translating into a 67% increase in the heart to body weight ratio (P < 0.05 for all parameters). The cell size was essentially the same between control and hypothermic hearts in all regions analysed. Likewise, there was no significant relationship between the cell size and heart weight; however, in the hypothermic hearts, there was a trend showing positive correlation between cell sizes in different cardiac regions and heart weight. Proliferation rate, determined on the basis of anti-phosphohistone H3 immunofluorescence, showed an overall increase in the hypothermic group, reaching statistical significance (P = 0.02, t-test) in the right ventricle. The proliferation rate was similar among different regions of the same heart. However, the correlation between the proliferation rate and heart weight was only small (r2 = 0.007 and r2 = 0.234 for the normothermic and hypothermic group, respectively). We thus conclude that hyperplasia is the predominant response mechanism in this volume-overload model; mechanistically, decreased heart rate at lower temperature increases the end-diastolic and stroke volume, minimizing the drop in cardiac output through the Frank- Starling mechanism.
- MeSH
- fluorescenční protilátková technika MeSH
- hyperplazie metabolismus MeSH
- hypertrofie metabolismus patofyziologie MeSH
- kardiomyocyty MeSH
- kuřecí embryo MeSH
- myokard cytologie metabolismus MeSH
- proliferace buněk fyziologie MeSH
- tepový objem fyziologie MeSH
- terapeutická hypotermie metody MeSH
- velikost orgánu fyziologie MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Using scaffolds with appropriate porosity represents a potential approach for repair of critical-size bone defects. Vascularization is essential for bone formation and healing. This study investigates methods for monitoring angiogenesis within porous biopolymer scaffolds on the basis of polyhydroxybutyrate (PHB)/chitosan. We use the chick and quail chorioallantoic membrane (CAM) assay as an in vivo model focused on the formation of new blood vessels inside the implant structure. Chemical properties of the surface in biopolymer scaffold matrix were characterized as well as the tissue reaction of the CAM. Implantation of a piece of polymer scaffold results in vascular reaction, documented visually and by ultrasound biomicroscopy. Histological analysis shows myofibroblast reaction (smooth muscle actin-positive cells) without excessive collagen deposition. Cell invasion is observed inside the implant, and QH1 marker, detecting hemangioblasts and endothelial cells of quail origin, confirms the presence of vascular network. The CAM assay is a rapid and easy way to test biocompatibility and vasculogenic potential of new candidate scaffolds for bone tissue bioengineering with respect to the 3R´ s.
- MeSH
- biokompatibilní materiály MeSH
- chorioalantoická membrána krevní zásobení fyziologie MeSH
- fyziologická neovaskularizace fyziologie MeSH
- kosti a kostní tkáň * MeSH
- křepelky a křepelovití MeSH
- kuřecí embryo MeSH
- regenerace kostí fyziologie MeSH
- tkáňové inženýrství * MeSH
- tkáňové podpůrné struktury * MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
SCOPE: Intake of flavonoids from the diet can be substantial, and epidemiological studies suggest that these compounds can decrease the incidence of cardiovascular diseases by involvement with increased platelet aggregation. Although parent flavonoids possess antiplatelet effects, the clinical importance is disputable due to their very low bioavailability. Most of them are metabolized by human colon bacteria to smaller phenolic compounds, which reach higher plasma concentrations than the parent flavonoids. In this study, a series of 29 known flavonoid metabolites is tested for antiplatelet potential. METHODS AND RESULTS: Four compounds appear to have a biologically relevant antiplatelet effect using whole human blood. 4-Methylcatechol (4-MC) is clearly the most efficient being about 10× times more active than clinically used acetylsalicylic acid. This ex vivo effect is also confirmed using a potentially novel in-vivo-like ex ovo hen's egg model of thrombosis, where 4-MC significantly increases the survival of the eggs. The mechanism of action is studied and it seems that it is mainly based on the influence on intracellular calcium signaling. CONCLUSION: This study shows that some flavonoid metabolites formed by human microflora have a strong antiplatelet effect. This information can help to explain the antiplatelet potential of orally given flavonoids.
- MeSH
- agregace trombocytů účinky léků MeSH
- inhibitory agregace trombocytů farmakologie MeSH
- inhibitory cyklooxygenasy farmakologie MeSH
- inhibitory enzymů farmakologie MeSH
- katecholy farmakologie MeSH
- kuřecí embryo MeSH
- kyselina arachidonová farmakologie MeSH
- lidé MeSH
- preklinické hodnocení léčiv metody MeSH
- pyrogalol farmakologie MeSH
- serotonin metabolismus MeSH
- thromboxan-A synthasa antagonisté a inhibitory MeSH
- trombóza farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
