1. Investigación

The use of cadavers is essential for veterinary anatomy learning. However, facing an animal corpse can be stressful for veterinary students because of their empathy toward animals. The objective of this study was to evaluate veterinary medicine students' emotions, feelings, and anxiety levels related to practicals with dog cadavers. Two questionnaires were administered to 1st year students (n = 168) at CEU Cardenal Herrera University in Valencia (Spain) before and after their first practical session with cadavers. The application of State–Trait Anxiety Inventory questionnaires showed that “state anxiety” decreased significantly (p < 0.05), from a score of 14.8 before the practical to 10.4 after, and that female students showed higher but not significantly different levels than males. Most (64%) of the students were not willing to donate the bodies of their pets, and those students were more stressed before the practical than their peers, although their anxiety levels significantly decreased by the end of the session. The majority of the students answered positively about emotions, such as feeling calm, safe, not nervous, relaxed and not worried before the practical, and this increased significantly to more than 80% by the end of the session. The visualization of educational videos prior to the session was evaluated positively by students. These results agree with those reported in other health science disciplines, showing that students face practical sessions with corpses in a similar way and suggesting that the use of videos can help decrease anxiety and enhance their learning experience.

Ultrasound-guided quadratus lumborum block (QLB) is a locoregional technique described in canine cadavers. The aim of this study was to assess a modified approach to QLB to minimise potential complications such as abdominal organ puncture. Nine canine cadavers were included and were positioned in lateral recumbency. An ultrasound-guided QLB was performed on each side. The probe was placed in the transverse position over the lumbar muscles just caudal to the last rib, and a needle was advanced in-plane from a dorso-lateral to a ventro-medial. A volume of 0.2 mL kg􀀀1 of a mixture of iomeprol and methylene blue was injected. Computed tomography (CT) and dissection were performed to evaluate the spreading. Success was defined as staining of the nerve with a length of more than 0.6 cm. Potential complications such as intra-abdominal, epidural, or intravascular spreading of the mixture were also assessed. The CT images showed a T13 to L7 vertebra distribution, with a median of 5 (3–6). Dissection showed staining of the nerves from T13 to L4, with a median of 3 (2–5). No complications were found. This modified approach to QLB is safe and shows similar results to the previous studies in canine carcass.

Rho small GTPases are proteins with key roles in the development of the central nervous system. Rnd proteins are a subfamily of Rho GTPases characterized by their constitutive activity. Rnd3/RhoE is a member of this subfamily ubiquitously expressed in the CNS, whose specific functions during brain development are still not well defined. Since other Rho proteins have been linked to the myelination process, we study here the expression and function of Rnd3 in oligodendrocyte development. We have found that Rnd3 is expressed in a subset of oligodendrocyte precursor cells and of mature oligodendrocytes both in vivo and in vitro. We have analyzed the role of Rnd3 in myelination using mice lacking Rnd3 expression (Rnd3gt/gt mice), showing that these mice exhibit hypomyelination in the brain and a reduction in the number of mature and total oligodendrocytes in the corpus callosum and striatum. The mutants display a decreased expression of several myelin proteins and a reduction in the number of myelinated axons. In addition, myelinated axons exhibit thinner myelin sheaths. In vitro experiments using Rnd3gt/gt mutant mice showed that the differentiation of the precursor cells is altered in the absence of Rnd3 expression, suggesting that Rnd3 is directly required for the differentiation of oligodendrocytes and, in consequence, for the correct myelination of the CNS. This work shows Rnd3 as a new protein involved in oligodendrocyte maturation, opening new avenues to further study the function of Rnd3 in the development of the central nervous system and its possible involvement in demyelinating diseases.