The utilization of 3D printing- digital light processing (DLP) technique, for the direct fabrication of microneedles encounters the problem of drug solubility in printing resin, especially if it is predominantly composed of water. The possible solution how to ensure ideal belonging of drug and water-based printing resin is its pre-formulation in nanosuspension such as nanocrystals. This study investigates the feasibility of this approach on a resin containing nanocrystals of imiquimod (IMQ), an active used in (pre)cancerous skin conditions, well known for its problematic solubility and bioavailability. The resin blend of polyethylene glycol diacrylate and N-vinylpyrrolidone, and lithium phenyl-2,4,6-trimethylbenzoylphosphinate as a photoinitiator, was used, mixed with IMQ nanocrystals in water. The final microneedle-patches had 36 cylindrical microneedles arranged in a square grid, measuring approximately 600 μm in height and 500 μm in diameter. They contained 5wt% IMQ, which is equivalent to a commercially available cream. The homogeneity of IMQ distribution in the matrix was higher for nanocrystals compared to usual crystalline form. The release of IMQ from the patches was determined ex vivo in natural skin and revealed a 48% increase in efficacy for nanocrystal formulations compared to the crystalline form of IMQ.
- MeSH
- 3D tisk * MeSH
- aplikace kožní MeSH
- imichimod * chemie aplikace a dávkování MeSH
- jehly * MeSH
- kožní absorpce MeSH
- kůže metabolismus MeSH
- lékové transportní systémy přístrojové vybavení MeSH
- mikroinjekce přístrojové vybavení MeSH
- nanočástice * chemie aplikace a dávkování MeSH
- polyethylenglykoly chemie aplikace a dávkování MeSH
- povidon chemie MeSH
- rozpustnost * MeSH
- uvolňování léčiv MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In several species, including Xenopus, mouse and human, two members of cyclin A family were identified. Cyclin A2, which is ubiquitously expressed in dividing cells and plays role in DNA replication, entry into mitosis and spindle assembly, and cyclin A1, whose function is less clear and which is expressed in spermatocytes, leukemia cells and in postmitotic multiciliated cells. Deletion of the gene showed that cyclin A1 is essential for male meiosis, but nonessential for female meiosis. Our results revealed, that the cyclin A1 is not only dispensable in oocytes, we show here that its expression is in fact undesirable in these cells. Our data demonstrate that the APC/C and proteasome in oocytes are unable to target sufficiently cyclin A1 before anaphase, which leads into anaphase arrest and direct inhibition of separase. The cyclin A1-induced cell cycle arrest is oocyte-specific and the presence of cyclin A1 in early embryos has no effect on cell cycle progression or chromosome division. Cyclin A1 is therefore not only an important cell cycle regulator with biased expression in germline, being essential for male and damaging for female meiosis, its persistent expression during anaphase in oocytes shows fundamental differences between APC/C function in oocytes and in early embryos.
- MeSH
- anafáze * MeSH
- cyklin A1 fyziologie MeSH
- cyklin A2 fyziologie MeSH
- fluorescenční mikroskopie MeSH
- meióza MeSH
- metafáze MeSH
- mikroinjekce MeSH
- myši MeSH
- oocyty cytologie MeSH
- proteasomový endopeptidasový komplex fyziologie MeSH
- segregace chromozomů * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
As stated by Korpáš and Tomori (1979), cough is the most important airway protective reflex which provides airway defensive responses to nociceptive stimuli. They recognized that active expiratory efforts, due to the activation of caudal ventral respiratory group (cVRG) expiratory premotoneurons, are the prominent component of coughs. Here, we discuss data suggesting that neurons located in the cVRG have an essential role in the generation of both the inspiratory and expiratory components of the cough reflex. Some lines of evidence indicate that cVRG expiratory neurons, when strongly activated, may subserve the alternation of inspiratory and expiratory cough bursts, possibly owing to the presence of axon collaterals. Of note, experimental findings such as blockade or impairment of glutamatergic transmission to the cVRG neurons lead to the view that neurons located in the cVRG are crucial for the production of the complete cough motor pattern. The involvement of bulbospinal expiratory neurons seems unlikely since their activation affects differentially expiratory and inspiratory muscles, while their blockade does not affect baseline inspiratory activity. Thus, other types of cVRG neurons with their medullary projections should have a role and possibly contribute to the fine tuning of the intensity of inspiratory and expiratory efforts.
- MeSH
- 6-kyano-7-nitrochinoxalin-2,3-dion aplikace a dávkování MeSH
- antagonisté excitačních aminokyselin aplikace a dávkování MeSH
- kašel patofyziologie prevence a kontrola MeSH
- lidé MeSH
- mechanika dýchání účinky léků fyziologie MeSH
- medulla oblongata účinky léků fyziologie MeSH
- mikroinjekce metody MeSH
- nadechnutí účinky léků fyziologie MeSH
- nervus phrenicus účinky léků fyziologie MeSH
- neurony účinky léků fyziologie MeSH
- reflex účinky léků fyziologie MeSH
- vydechnutí účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The functional significance of having two nuclei in a cell is unknown. Having two stores of genetic material may be advantageous for cell growth. Nuclear protein import is at a critical juncture in the cell to modify cell growth. This study addressed the potential for differential nuclear protein import in two nuclei of the same cell. Isolated adult rat cardiomyocytes were microinjected with an exogenous fluorescent protein conjugated with nuclear localization amino acid sequences to facilitate nuclear import and its detection. Our results demonstrate the rate of nuclear protein import was not significantly different between the two nuclei in the same cell. These data demonstrate that the two nuclei are functionally similar in a binucleated cardiomyocyte, at least as far as nucleocytoplasmic transport is concerned.
BACKGROUND: CRISPR-Cas9 gene-editing technology has facilitated the generation of knockout mice, providing an alternative to cumbersome and time-consuming traditional embryonic stem cell-based methods. An earlier study reported up to 16% efficiency in generating conditional knockout (cKO or floxed) alleles by microinjection of 2 single guide RNAs (sgRNA) and 2 single-stranded oligonucleotides as donors (referred herein as "two-donor floxing" method). RESULTS: We re-evaluate the two-donor method from a consortium of 20 laboratories across the world. The dataset constitutes 56 genetic loci, 17,887 zygotes, and 1718 live-born mice, of which only 15 (0.87%) mice contain cKO alleles. We subject the dataset to statistical analyses and a machine learning algorithm, which reveals that none of the factors analyzed was predictive for the success of this method. We test some of the newer methods that use one-donor DNA on 18 loci for which the two-donor approach failed to produce cKO alleles. We find that the one-donor methods are 10- to 20-fold more efficient than the two-donor approach. CONCLUSION: We propose that the two-donor method lacks efficiency because it relies on two simultaneous recombination events in cis, an outcome that is dwarfed by pervasive accompanying undesired editing events. The methods that use one-donor DNA are fairly efficient as they rely on only one recombination event, and the probability of correct insertion of the donor cassette without unanticipated mutational events is much higher. Therefore, one-donor methods offer higher efficiencies for the routine generation of cKO animal models.
- MeSH
- alely * MeSH
- blastocysta metabolismus MeSH
- CRISPR-Cas systémy genetika MeSH
- faktorová analýza statistická MeSH
- mikroinjekce MeSH
- myši knockoutované MeSH
- protein 2 vázající methyl-CpG genetika metabolismus MeSH
- protein Cas9 metabolismus MeSH
- regresní analýza MeSH
- reprodukovatelnost výsledků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Biogenesis of spliceosomal snRNAs is a complex process involving both nuclear and cytoplasmic phases and the last step occurs in a nuclear compartment called the Cajal body. However, sequences that direct snRNA localization into this subnuclear structure have not been known until recently. To determine sequences important for accumulation of snRNAs in Cajal bodies, we employed microinjection of fluorescently labelled snRNAs followed by their localization inside cells. First, we prepared snRNA deletion mutants, synthesized DNA templates for in vitro transcription and transcribed snRNAs in the presence of UTP coupled with Alexa488. Labelled snRNAs were mixed with 70 kDa-Dextran conjugated with TRITC, and microinjected to the nucleus or the cytoplasm of human HeLa cells. Cells were incubated for 1 h and fixed and the Cajal body marker coilin was visualized by indirect immunofluorescence, while snRNAs and dextran, which serves as a marker of nuclear or cytoplasmic injection, were observed directly using a fluorescence microscope. This method allows for efficient and rapid testing of how various sequences influence RNA localization inside cells. Here, we show the importance of the Sm-binding sequence for efficient localization of snRNAs into the Cajal body.
- MeSH
- HeLa buňky MeSH
- lidé MeSH
- mikroinjekce metody MeSH
- RNA malá jaderná metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- práce podpořená grantem MeSH
Here we report in vitro and term development of sheep embryos after the inner cell mass (ICM) from one set of sheep blastocysts were injected into the trophoblast vesicles of another set. We also observed successful in vitro development of chimeric blastocysts made from sheep trophoblast vesicles injected with bovine ICM. First, we dissected ICMs from 35 sheep blastocysts using a stainless steel microblade and injected them into 29 re-expanded sheep trophoblastic vesicles. Of the 25 successfully micromanipulated trophoblastic vesicles, 15 (51.7%) re-expanded normally and showed proper ICM integration. The seven most well reconstructed embryos were transferred for development to term. Three ewes receiving manipulated blastocysts were pregnant at day 45 (42.8%), and all delivered normal offspring (singletons, two females and one male, average weight: 3.54 ± 0.358 kg). Next, we monitored in vitro development of sheep trophoblasts injected with bovine ICMs. Of 17 injected trophoblastic vesicles, 10 (58.8%) re-expanded after 4 h in culture, and four (40%) exhibited integrated bovine ICM. Our results indicate that ICM/trophoblast exchange is feasible, allowing full term development with satisfactory lambing rate. Therefore, ICM exchange is a promising approach for endangered species conservation.
- MeSH
- chiméra embryologie MeSH
- ektogeneze * MeSH
- embryoblast cytologie MeSH
- fertilizace in vitro veterinární MeSH
- IVM techniky veterinární MeSH
- jatka MeSH
- klonování organismů veterinární MeSH
- mikroinjekce veterinární MeSH
- mikromanipulace veterinární MeSH
- novorozená zvířata MeSH
- ovce domácí MeSH
- ověření koncepční studie MeSH
- přenos embrya veterinární MeSH
- skot MeSH
- studie proveditelnosti MeSH
- těhotenství MeSH
- trofoblasty cytologie MeSH
- vývoj plodu * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- skot MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Itálie MeSH
Salusin-beta is newly identified bioactive peptide of 20 amino acids, which is widely distributed in hematopoietic system, endocrine system, and the central nervous system (CNS). Although salusin-beta extensively expressed in the CNS, the central cardiovascular functions of salusin-beta are unclear. Our main objective was to determine the cardiovascular effect of microinjection of salusin-beta into the nucleus tractus solitarii (NTS) in anesthetized rats. Bilateral or unilateral microinjection of salusin-beta (0.94-94 microg/rat) into the NTS dose-dependently decreased blood pressure and heart rate. Bilateral NTS microinjection of salusin-beta (9.4 microg/rat) did not alter baroreflex sensitivity. Prior application of the glutamate receptor antagonist kynurenic acid (0.19 microg/rat, n=9) into the NTS did not alter the salusin-beta (9.4 microg/rat) induced hypotension and bradycardia. However, pretreatment with the GABA receptor agonist muscimol (0.5 ng/rat) within the rostral ventrolateral medulla (RVLM) completely abolished the hypotension (-14+/-5 vs. -3+/-5 mm Hg, P<0.05) and bradycardia (-22+/-6 vs. -6+/-5 bpm, P<0.05) evoked by intra-NTS salusin-beta (9.4 microg/rat). In addition, we found that vagotomy didn't influence the actions of salusin-beta (9.4 microg/rat) in the NTS. In conclusion, our present study shows that microinjection of salusin-beta into the NTS significantly produces hypotension and bradycardia, presumably by suppressing the activities of presympathetic neurons in the RVLM.
- MeSH
- antagonisté excitačních aminokyselin farmakologie MeSH
- baroreflex účinky léků MeSH
- bradykardie chemicky indukované patofyziologie MeSH
- GABA antagonisté farmakologie MeSH
- hemodynamika účinky léků MeSH
- hypotenze chemicky indukované patofyziologie MeSH
- krysa rodu rattus MeSH
- kyselina kynurenová farmakologie MeSH
- medulla oblongata cytologie účinky léků MeSH
- mezibuněčné signální peptidy a proteiny aplikace a dávkování farmakologie MeSH
- mikroinjekce MeSH
- muscimol farmakologie MeSH
- neurony účinky léků MeSH
- nucleus solitarius účinky léků MeSH
- potkani Sprague-Dawley MeSH
- sympatický nervový systém účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Primordial germ cells (PGCs) are the origin of all germ cells in developing embryos. In the sturgeon embryo, PGCs develop from the vegetal hemisphere, which mainly acts as an extraembryonic source of nutrition. Current methods for studying sturgeon PGCs require either killing the fish or using costly and time-consuming histological procedures. Here, we demonstrate that visualization of sterlet (Acipenser ruthenus>) PGCs in vivo is feasible by simply labeling the vegetal hemisphere with fluorescein isothiocyanate (FITC)-dextran. We injected FITC-dextrans, with molecular weights varying between 10 000 and 2 000 000, into the vegetal pole of 1- to 4-cell stage embryos. At the neurula to tail-bud developmental stages, FITC-positive PGC-like cells appeared ventrally around the developing tail bud in the experimental group that received a high-molecular-weight FITC-dextran. The highest average number of FITC-positive PGC-like cells was observed in embryos injected with FITC-dextran having a molecular weight of 500 000 (FD-500). The pattern of migration of the labeled cells was identical to that of PGCs, clearly indicating that the FITC-positive PGC-like cells were PGCs. Labeled vegetal cells, except for the PGCs, were digested and excreted before the embryos starting feeding. FITC-labeled PGCs were observed in the developing gonads of fish for at least 3 mo after injection. We also found that FD-500 could be used to visualize PGCs in other sturgeon species. To the best of our knowledge, this report is the first to demonstrate in any animal species that PGCs can be visualized in vivo for a long period by the injection of a simple reagent.
- MeSH
- bičík spermie ultrastruktura MeSH
- dextrany MeSH
- embryo nesavčí ultrastruktura MeSH
- embryonální vývoj fyziologie MeSH
- fluorescein-5-isothiokyanát analogy a deriváty MeSH
- fluorescenční barviva MeSH
- mikroinjekce MeSH
- molekulová hmotnost MeSH
- pohyb buněk MeSH
- ryby fyziologie MeSH
- zárodečné buňky ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The pig has emerged as an important large animal model in biomedical and pharmaceutical research. We describe a protocol for high-efficiency germline transgenesis and sustained transgene expression in pigs by using the Sleeping Beauty (SB) transposon system. The protocol is based on co-injection of a plasmid encoding the SB100X hyperactive transposase, together with a second plasmid carrying a transgene flanked by binding sites for the transposase, into the cytoplasm of porcine zygotes. The transposase mediates excision of the transgene cassette from the plasmid vector and its permanent insertion into the genome to produce stable transgenic animals. This method compares favorably in terms of both efficiency and reliable transgene expression to classic pronuclear microinjection or somatic cell nuclear transfer (SCNT), and it offers comparable efficacies to lentiviral approaches, without limitations on vector design, issues of transgene silencing and the toxicity and biosafety concerns of working with viral vectors. Microinjection of the vectors into zygotes and transfer of the embryos to recipient animals can be performed in 1 d; generation of germline-transgenic lines by using this protocol takes ∼1 year.
- MeSH
- genetické vektory MeSH
- geneticky modifikovaná zvířata * MeSH
- genom MeSH
- mikroinjekce MeSH
- prasata genetika MeSH
- technika přenosu genů * MeSH
- transposasy MeSH
- transpozibilní elementy DNA * MeSH
- zárodečné buňky MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
