Peripheral nerve injury remains a medical challenge with no easy resolution. Over the last few decades, significant advances have been achieved in promoting peripheral nerve regeneration, and new assessment tools have been developed, both functional and imaging, to quantify the proportion and quality of nerve recovery. The exploration of new animal models, larger, more complex and with more similarities to humans, has made it possible to reduce the gap between the results obtained in classic animal models such as rodents and the application of new therapies in humans and animals of clinical interest. Ultrasonography is an imaging technique recurrently used in clinical practice to assess the peripheral nerves, allowing its anatomical and topographic characterization, and aiding in the administration of anesthesia and in the performance of nerve blocks. The use of this technique in animal models is scarce, but it could be a useful tool in monitoring the progression of nerve regeneration after the induction of controlled experimental lesions. In this work, sheep, a promising animal model in the area of peripheral nerve regeneration, were subjected to an ultrasonographic study of three peripheral nerves of the hind limb, the common peroneal, tibial and sciatic nerves, in order to establish values of dimensions and ultrasound appearance in healthy nerves and also landmarks for their identification. At the same time, an echographic evaluation of the cranial tibial muscle, an effector muscle of the common peroneal nerve, was also carried out, establishing normal values for the echographic aspect and dimensions. The results obtained will allow the use of these data as control values in future work exploring new therapeutic options for nerve regeneration after induction of common peroneal nerve injuries in sheep.

Horses are high performance athletes prone to sportive injuries such as tendonitis and desmitis. The formation of fibrous tissue in tendon repair becomes a therapeutic challenge to overcome. This impels regenerative medicine to develop innovative therapies that enhance tissue regenera-tion retrieving original tissue properties. Multipotent Mesenchymal Stem/ Stromal Cells (MSCs) have been successfully used to develop therapeutic products, as they secrete a variety of bioac-tive molecules that play a pivotal role in tissue regeneration. These factors are released in cul-ture media producing conditioned media (CM). The aforementioned assumptions led to the formulation of equine synovial membrane MSCs (eSM-MSCs) – the cellular pool that naturally regenerates joint tissue, combined with medium enriched in immunomodulatory factors (among other bioactive factors) produced by umbilical cord stroma-derived MSCs (eUC-MSCs), that nat-urally contribute to suppress the immune rejection in the maternal-fetal barrier. A clinical case of an equine acute desmitis, treated with this formulation is presented. Ultrasonographic ligament regeneration occurred in a reduced time frame, reducing stoppage time and allowing return to unrestricted competition after completion of a physical rehabilitation program. This study fo-cused on the determination of the formulation therapeutic potential and the evaluation of its synergistic effect in an equine desmitis treatment, utilizing the cells themselves and its secretome.

Horses are high performance athletes prone to sportive injuries such as tendonitis and desmitis. Fibrous tissue formation with loss of mechanical properties occurs in tendon repair, becoming a therapeutic challenge to overcome. This impels regenerative medicine to develop innovative therapies that enhance tissue regeneration retrieving original tissue properties. Mesenchymal stem cells (MSCs) have been successfully used to develop therapeutic products. They secrete a variety of bioactive molecules that play a pivotal role in tissue regeneration. These factors are released in culture media producing conditioned media (CM). The aforementioned assumptions impelled us to formulate equine synovial membrane stem cells (eSM-MSCs) – the cellular pool that naturally regenerates joint tissue, combined with medium enriched in immunomodulatory factors produced by umbilical cord stroma-derived MSCs (eUC-MSCs), that naturally contribute to suppress the immune rejection in the maternal-fetal frontier. A clinical case of an equine acute desmitis, treated with the abovementioned formulation is presented. Ligament regeneration occurred in a reduced time frame, reducing stoppage time, allowing return to unrestricted competition after completion of a physical rehabilitation program. This study focus was determination of the formulation therapeutic potential and the evaluation of its synergistic effect in an equine desmitis treatment, utilizing the cells themselves and its secretome.

Additive manufacturing or 3D printing applying polycaprolactone-(PCL)-based medical devices represents an important branch of tissue engineering, where the sterilization method is a key process for further safe application in vitro and in vivo. In this study, the authors intend to access the most suitable gamma radiation conditions to sterilize PCL-based scaffolds in a preliminary biocompatibility assessment, envisioning future studies for airway obstruction conditions. Three radiation levels were considered, 25 kGy, 35 kGy and 45 kGy and evaluated as to their cyto- and biocompatibility. All three groups presented biocompatible properties, indicating an adequate sterility condition. As for the cytocompatibility analysis, devices sterilized by 35 kGy and 45 kGy showed better results, with the 45 kGy showing overall improved outcomes. This study allowed to select the most suitable sterilization condition for PCL-based scaffolds, aiming at immediate future assays, by applying 3D-customized printing techniques to specific airway obstruction lesions of the trachea.

Tendons and ligaments injuries are frequent in sport horses and humans, representing a great therapeutic challenge. Tissue regeneration and function recovery are the paramount of tendon and ligament lesions management. Nowadays, several regenerative treatments are being developed, based on the use of stem cell and stem cell-based therapies. In the present study, the preparation of equine synovial membrane mesenchymal stem cells (eSM-MSCs) for clinical use - collection, transport, isolation, differentiation, characterization, and application is described. These cells are fibroblast-like and grow in clusters. They retain an osteogenic, chondrogenic and adipogenic differentiation potential. 16 clinical cases of tendonitis and desmitis, treated with allogenic eSM-MSCs and autologous serum are also presented, including their evaluation, treatment and follow-up. The use of autologous serum as a vehicle concern to a decreased immunogenic response after the administration of this combination and to its healing properties, due to the presence of growth factors and immunoglobulins. Most of the cases (14/16), healed in 30 days and presented a good outcome. Treatment of tendon and ligament lesions with the mixture of eSM-MSCs and autologous serum appears to be a promising clinical option for this category of lesions in equine patients.

This prospective cohort pilot study included 22 cats diagnosed with partial traumatic brachial plexus injury (PTBPI), aiming to explore the response of an early intensive neurorehabilitation protocol. This protocol included functional electrical stimulation (FES), locomotor treadmill training and kinesiotherapy exercises, starting at the time with highest probability of nerve repair. The synergetic benefits of this multimodal approach were based on the structural and protective role of proteins and release of neurotrophic factors. Furthermore, parametrization of FES was according to presence or absence of deep pain. Results have shown 72.6% (16/22) cats that achieved ambulation, with 9 cats within 15 days, 2 cats until 30 days and 5 cats until 60 days, however with persistent knuckling position. During the 4 years follow-up, there was evidence of improvement on both muscle mass and muscle weakness, in addition to the disappearance of neuropathic pain. Notably, after the 60 days of neurorehabilitation, 3 cats improved ambulation after arthrodesis of the carpus. Thus, early rehabilitation, with FES applied at the first weeks after injury and accurate parametrization according to deep pain perception, may improve functionality and ambulation, reducing probability of amputation of the affected limb.