Evaluation of a Simple Antibiotic-Free Cryopreservation Protocol for Drone Semen.

The increasing reliance of modern agriculture on honey bee () pollination has driven efforts to preserve and enhance bee populations. The cryopreservation of drone semen presents a promising solution for preserving genetic diversity and supporting breeding programs without live animal transport risks. This study aimed to evaluate a one-step dilution antibiotic-free drone semen slow-freezing protocol under field conditions with in vitro and in vivo parameters.

Validation of Calcein Violet as a New Marker of Semen Membrane Integrity in Domestic Animals.

Many fluorochromes routinely used in semen quality analysis emit in the green and red channels, limiting their possible combination for multiple parameter analysis. The use of fluorophores emitting in different light channels broadens the possibilities of combination to expand the range of simultaneously evaluated criteria. This is of great interest in cases of small ejaculated volumes, such as those naturally occurring in roosters, small dog breeds and drones ().

Subunit composition, molecular environment, and activation of native TRPC channels encoded by their interactomes.

In the mammalian brain TRPC channels, a family of Ca-permeable cation channels, are involved in a variety of processes from neuronal growth and synapse formation to transmitter release, synaptic transmission and plasticity. The molecular appearance and operation of native TRPC channels, however, remained poorly understood. Here, we used high-resolution proteomics to show that TRPC channels in the rodent brain are macro-molecular complexes of more than 1 MDa in size that result from the co-assembly of the tetrameric channel core with an ensemble of interacting proteins (interactome).

Eye Infection with SARS-CoV-2 as a Route to Systemic Immunization?

Unlabelled: Infectious diseases of the conjunctiva and cornea usually leave behind both broad local and systemic immunity. Case reports of SARS-CoV-2-positive conjunctivitis with subsequent systemic immunity suggest a new route of immunization preventing the primary infection of the airways.

Material And Methods: A total of 24 Syrian field hamsters were treated.

Bitter taste signaling in tracheal epithelial brush cells elicits innate immune responses to bacterial infection.

Constant exposure of the airways to inhaled pathogens requires efficient early immune responses protecting against infections. How bacteria on the epithelial surface are detected and first-line protective mechanisms are initiated are not well understood. We have recently shown that tracheal brush cells (BCs) express functional taste receptors.

Lung emphysema and impaired macrophage elastase clearance in mucolipin 3 deficient mice.

Lung emphysema and chronic bronchitis are the two most common causes of chronic obstructive pulmonary disease. Excess macrophage elastase MMP-12, which is predominantly secreted from alveolar macrophages, is known to mediate the development of lung injury and emphysema. Here, we discovered the endolysosomal cation channel mucolipin 3 (TRPML3) as a regulator of MMP-12 reuptake from broncho-alveolar fluid, driving in two independently generated Trpml3 mouse models enlarged lung injury, which is further exacerbated after elastase or tobacco smoke treatment.

Odontoblast TRPC5 channels signal cold pain in teeth.

Teeth are composed of many tissues, covered by an inflexible and obdurate enamel. Unlike most other tissues, teeth become extremely cold sensitive when inflamed. The mechanisms of this cold sensation are not understood.

GPR101 drives growth hormone hypersecretion and gigantism in mice via constitutive activation of G and G.

Growth hormone (GH) is a key modulator of growth and GH over-secretion can lead to gigantism. One form is X-linked acrogigantism (X-LAG), in which infants develop GH-secreting pituitary tumors over-expressing the orphan G-protein coupled receptor, GPR101. The role of GPR101 in GH secretion remains obscure.

Analysis of prolactin receptor expression in the murine brain using a novel prolactin receptor reporter mouse.

Prolactin influences a wide range of physiological functions via actions within the central nervous system, as well as in peripheral tissues. A significant limitation in studies investigating these functions is the difficulty in identifying prolactin receptor (Prlr) expression, particularly in the brain. We have developed a novel mouse line using homologous recombination within mouse embryonic stem cells to produce a mouse in which an internal ribosome entry site (IRES) followed by Cre recombinase cDNA is inserted immediately after exon 10 in the Prlr gene, thereby targeting the long isoform of the Prlr.

Relationship between follicular volume and oocyte competence, blastocyst development and live-birth rate: optimal follicle size for oocyte retrieval.

Objective: To analyze oocyte competence in gonadotropin-releasing hormone agonist (GnRHa) stimulation cycles with regard to maturity, fertilization and blastocyst rate, as well as clinical outcome (pregnancy and live-birth rate), in relation to follicular volume, measured by three-dimensional transvaginal sonography (3D-TVS), and follicular fluid composition.

Methods: This was a prospective single-center study conducted between June 2012 and June 2014, including 118 ovum pick-ups with subsequent embryo transfer. Ovarian stimulation was performed using the GnRHa long protocol.

Cryopreservation of chicken primordial germ cells by vitrification and slow freezing: A comparative study.

In the present study, we compare a classical slow freezing (SLF) method and an aseptic vitrification (Vitrif) technique to cryopreserve a stable primordial germ cell (PGCs) line issued from the Ardennaise chicken breed. Viability immediately after warming was close to 80% and did not differ between the two cryopreservation methods. Proliferation tended to be slower for both cryopreservation methods compared with controls, but the difference was significant only for Vitrif.

Ectopic Expression of Retrotransposon-Derived PEG11/RTL1 Contributes to the Callipyge Muscular Hypertrophy.

The callipyge phenotype is an ovine muscular hypertrophy characterized by polar overdominance: only heterozygous +Mat/CLPGPat animals receiving the CLPG mutation from their father express the phenotype. +Mat/CLPGPat animals are characterized by postnatal, ectopic expression of Delta-like 1 homologue (DLK1) and Paternally expressed gene 11/Retrotransposon-like 1 (PEG11/RTL1) proteins in skeletal muscle. We showed previously in transgenic mice that ectopic expression of DLK1 alone induces a muscular hypertrophy, hence demonstrating a role for DLK1 in determining the callipyge hypertrophy.

Long term-cultured and cryopreserved primordial germ cells from various chicken breeds retain high proliferative potential and gonadal colonisation competency.

When derived from chicken embryos, avian primordial germ cells (PGCs) have been reported to keep their germline-specific properties and proliferative potential even after long-term culture and genetic modifications. Few teams to date have reported such long-term expansion and engineering without differentiation of primary avian PGCs' cultures. We have developed original and robust methods that allow more than 1 year culture, expansion and cryobanking of primary cultures of PGCs without obvious effects on their biological properties, including their ability to colonise the genital ridges.

Sensitivity and permissivity of Cyprinus carpio to cyprinid herpesvirus 3 during the early stages of its development: importance of the epidermal mucus as an innate immune barrier.

Cyprinid herpesvirus 3 (CyHV-3) causes a lethal disease in common and koi carp (Cyprinus carpio). The present study investigated the ability of CyHV-3 to infect common carp during the early stages of its development (from embryos to fingerlings) after inoculation by immersion in water containing the virus. Fish were inoculated at different times after hatching with a pathogenic recombinant CyHV-3 strain expressing luciferase.

Lower intracellular concentration of cryoprotectants after vitrification than after slow freezing despite exposure to higher concentration of cryoprotectant solutions.

Study Question: What is the intracellular concentration of cryoprotectant (ICCP) in mouse zygotes during vitrification (VIT) and slow-freezing (SLF) cryopreservation procedures?

Summary Answer: Contrary to common beliefs, it was observed that the ICCP in vitrified zygotes is lower than after SLF, although the solutions used in VIT contain higher concentrations of cryoprotectants (CPs).

What Is Known Already: To reduce the likelihood of intracellular ice crystal formation, which has detrimental effects on cell organelles and membranes, VIT was introduced as an alternative to SLF to cryopreserve embryos and gametes. Combined with high cooling and warming rates, the use of high concentrations of CPs favours an intracellular environment that supports and maintains the transition from a liquid to a solid glass-like state devoid of crystals.

Evidence for cross-talk between the LH receptor and LH during implantation in mice.

The present study investigated the first interaction that occurs between the blastocyst and endometrium during implantation. Given the ethical objections to studying implantation in humans, a mouse model was used to study the dialogue between luteinising hormone (LH) and luteinising hormone receptor (LHCGR). Several studies performed on LHCGR-knockout mice have generated controversy regarding the importance of the dialogue between LH and LHCGR during implantation.

Blastocyst transfer after aseptic vitrification of zygotes: an approach to overcome an impaired uterine environment.

In some IVF cycles, no fresh embryo transfer in the stimulated cycle is advisable. The cryopreservation of zygotes and the transfer of blastocysts in a cryo-embryo transfer is an option to circumvent an inadequate uterine environment due to risk of ovarian hyperstimulation syndrome, inappropriate endometrium build up, endometrial polyps or uterine myomas. For this strategy, highly secure and safe cryopreservation protocols are advisable.

[Vitrification and the use of high concentrations of cryoprotectants: is it a justified argument to prefer slow freezing?].

The use of high levels of cryoprotectants (CPs) in solutions applied to vitrify oocytes or embryos is an argument to still prefer slow freezing procedure. Is it a justified argument? Out of three studies using mice zygotes we may assume that (i) the intracellular concentration of CPs is far lower than the one in the vitrification solutions, (ii) the intracellular concentration of CPs in the vitrified zygote is in contrary to the common beliefs even lower than the one observed after a slow freezing procedure, (iii) survival after slow freezing reflects the presence of an intracellular vitrified state in these cells.

[Closed carrier device: a reality to vitrify oocytes and embryos in aseptic conditions].

Vitrification with the use of "Open" carrier devices (Cryoloop, cryotop, cryoleaf, Vitriplug) which allowed the contact with liquid nitrogen has become a more popular way to achieve cooling rate superior to 20,000 °C/min. Even though the question of contamination with liquid nitrogen during ultra-rapid cooling and storage remain debatable with the use of "open" devices, it is important to revise the carrier system in a way, which minimizes the risk of contamination. According to the EU tissues and cells directive, it is advisable that the cooling and storage should be carried out in embryo carrier devices ensuring complete separation of the embryos from liquid nitrogen in a way, which minimizes the risk of contamination.

Higher sensitivity of Adamts12-deficient mice to tumor growth and angiogenesis.

ADAMTS (a disintegrin and metalloproteinase domain with thrombospondin motifs) constitute a family of endopeptidases related to matrix metalloproteinases. These proteases have been largely implicated in tissue remodeling and angiogenesis associated with physiological and pathological processes. To elucidate the in vivo functions of ADAMTS-12, we have generated a knockout mouse strain (Adamts12(-/-)) in which Adamts12 gene was deleted.

Aseptic vitrification of blastocysts from infertile patients, egg donors and after IVM.

During embryo vitrification, it is advisable that cooling and storage should occur in a carrier device in which there is complete separation of the embryos from liquid nitrogen to ensure asepsis. The consequence of a reduction in the cooling rate resulting from the heat-insulating barrier aseptic devices has to be counteracted by gradually increasing intracellular concentrations of cryoprotectants without inducing a toxic effect. Blastocysts originating from couples with male and/or female factor infertility (group 1) or from oocyte donors (group 2) or from in-vitro matured oocytes (group 3) were gradually exposed to increasing concentrations of dimethylsulphoxide/ethylene glycol (5/5%, 10/10% and 20/20%) before aseptic vitrification using a specially designed carrier (VitriSafe), a modification of the open hemi-straw plug device.

Expression of Hoxa2 in cells entering chondrogenesis impairs overall cartilage development.

Vertebrate Hox genes act as developmental architects by patterning embryonic structures like axial skeletal elements, limbs, brainstem territories, or neural crest derivatives. While active during the patterning steps of development, these genes turn out to be down-regulated in specific differentiation programs like that leading to chondrogenesis. To investigate why chondrocyte differentiation is correlated to the silencing of a Hox gene, we generated transgenic mice allowing Cre-mediated conditional misexpression of Hoxa2 and induced this gene in Collagen 2 alpha 1-expressing cells committed to enter chondrogenesis.

[Cryopreservation of human embryos by vitrification].

Vitrification is a cryopreservation strategy where cells are converted into a glass-like amorphous solid which is free of any crystalline structure. Such process is achieved by a combination of high concentration of cryoprotectant and an extremely high cooling rate. In the last years, survival rates of up to 80% after thawing and pregnancy rates of almost 30% could be achieved after transfer of vitrified embryos at the zygote, cleavage, morula and blastocyst stages.