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This study aimed to evaluate the effectiveness of the experimental formulation containing chlamydospores of Duddingtonia flagrans and Pochonia chlamydosporia fungi, against Moniezia expansa . Two experiments were carried out. The first experiment evaluated the in vitro efficacy using 1 g of the experimental formulation (V1) added to 100 M. expansa eggs and the control (V2) (without the fungal formulation). Intact eggs or eggs with alterations were counted in order to evaluate their effectiveness. The second experiment evaluated the action of the fungal formulation on M. expansa eggs after passing through the gastrointestinal tract of goats. Three groups were identified as B1, B2, and B3, which received 1.0, 1.5 g of experimental fungal formulation, and placebo, respectively. In experiment 1, all the eggs in V1 were subjected to the predatory action of fungi, while in V2, the eggs remained intact. In experiment 2, the reduction of eggs in groups B1 and B2 were 49% and 57% 24 h after ingestion, 60% and 63% 48 h after, and 48% and 58% 72 h after. The predatory capacity against M. expansa eggs shown in the tests demonstrated that experimental fungal formulation has the potential to be used on integrated helminth control programs.

Converting biopolymers to extracellular matrix (ECM)-mimetic hydrogel-based scaffolds has provided invaluable opportunities to design in vitro models of tissues/diseases and develop regenerative therapies for damaged tissues. Among biopolymers, gelatin and its crosslinkable derivatives, such as gelatin methacryloyl (GelMA), have gained significant importance for biomedical applications due to their ECM-mimetic properties. Recently, we have developed the first class of in situ forming GelMA microporous hydrogels based on the chemical annealing of physically crosslinked GelMA microscale beads (microgels), which addressed several key shortcomings of bulk (nanoporous) GelMA scaffolds, including lack of interconnected micron-sized pores to support on-demand three-dimensional-cell seeding and cell-cell interactions. Here, we address one of the limitations of in situ forming microporous GelMA hydrogels, that is, the thermal instability (melting) of their physically crosslinked building blocks at physiological temperature, resulting in compromised microporosity. To overcome this challenge, we developed a two-step fabrication strategy in which thermostable GelMA microbeads were produced via semi-photocrosslinking, followed by photo-annealing to form stable microporous scaffolds. We show that the semi-photocrosslinking step (exposure time up to 90 s at an intensity of ~100 mW/cm 2 and a wavelength of ~365 nm) increases the thermostability of GelMA microgels while decreasing their scaffold forming (annealing) capability. Hinging on the tradeoff between microgel and scaffold stabilities, we identify the optimal crosslinking condition (exposure time ~60 s) that enables the formation of stable annealed microgel scaffolds. This work is a step forward in engineering in situ forming microporous hydrogels made up from thermostable GelMA microgels for in vitro and in vivo applications at physiological temperature well above the gelatin melting point., Competing Interests: The authors declare no potential conflict of interest., (© 2020 The Authors. Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)

Alterations to DNA methylation have been attributed to in vitro culture and may affect normal embryo development. We chose to analyze DNA methylation reprogramming in the rabbit which, of the species with delayed transcriptional activation of the embryonic genome, allows easy comparisons between in vivo-developed (IVD) and in vitro-cultured (IVC) embryos. In this species, variations in DNA methylation had not previously been quantified, even in IVD embryos. IVD and IVC embryos were recovered at the 2, 4, 8 and 16-cell, morula and blastocyst stages. Immunostaining for 5-methyl-cytidine and normalization of the quantity of methylated DNA vs. the total DNA content were then performed. Our quantitative results evidenced DNA demethylation during pre-implantation development in both IVD and IVC embryos, but with different kinetics. Demethylation occurred earlier in vitro than in vivo between the 2 and 8-cell stages in IVC embryos, reaching its lowest level, while it only started at the 4-cell stage and ended at the 16-cell stage in IVD embryos. We also showed that an absence of serum from the culture medium significantly altered the degree of DNA demethylation. Finally, at the blastocyst stage, ICM was more methylated than the trophectoderm in all cases. Despite a morphological delay observed in in vitro cultured blastocysts, the difference in DNA methylation between ICM and trophectoderm cells appeared at the same time post-fertilization in IVD and IVC embryos, which may reflect another difference in the dynamics of DNA methylation during blastocyst formation. Our data thus clearly establish an effect of embryonic environment on DNA methylation reprogramming during pre-implantation development in a non-rodent species.

(1) In this study, we examined the effects of crude venom from the spider Parawixia bistriata on glutamate and GABA uptake into synaptosomes prepared from rat cerebral cortex. Addition of venom to cortical synaptosomes stimulated glutamate uptake and inhibited GABA uptake in a concentration-dependent manner. (2) The venom was fractionated using reverse-phase high-performance liquid chromatography on a preparative column. The fraction that retained glutamate uptake-stimulating activity was further purified on a reverse-phase analytical column followed by ion-exchange chromatography. (3) The active fraction, referred to as PbTx1.2.3, stimulated glutamate uptake in synaptosomes without changing the K(M) value, and did not affect GABA uptake. Additional experiments showed that the enhancement of glutamate uptake by PbTx1.2.3 occurs when ionotropic glutamate receptors or voltage-gated sodium and calcium channels are completely inhibited or when GABA receptors and potassium channels are activated, indicating that the compound may have a direct action on the transporters. (4) In an experimental model for glaucoma in which rat retinas are subjected to ischemia followed by reperfusion, PbTx1.2.3 protected neurons from excitotoxic death in both outer and inner nuclear layers, and ganglion cell layers. (5) This active spider venom component may serve as a basis for designing therapeutic drugs that increase glutamate clearance and limit neurodegeneration.