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Background Sheep (Ovis aries) have been largely used as animal models in a multitude of specialties in biomedical research. The similarity to human brain anatomy in terms of brain size, skull features, and gyrification index, gives to ovine as a large animal model a better translational value than small animal models in neuroscience. Despite this evidence and the availability of advanced imaging techniques, morphometric brain studies are lacking. We herein present the morphometric ovine brain indexes and anatomical measures developed by two observers in a double-blinded study and validated via an intra- and inter-observer analysis. Results For this retrospective study, T1-weighted Magnetic Resonance Imaging (MRI) scans were performed at 1.5 T on 15 sheep, under general anaesthesia. The animals were female Ovis aries, in the age of 18-24 months. Two observers assessed the scans, twice time each. The statistical analysis of intra-observer and inter-observer agreement was obtained via the Bland-Altman plot and Spearman rank correlation test. The results are as follows (mean ± Standard deviation): Indexes: Bifrontal 0,338 ± 0,032 cm; Bicaudate 0,080 ± 0,012 cm; Evans’ 0,218 ± 0,035 cm; Ventricular 0,241 ± 0,039 cm; Huckman 1693 ± 0,174 cm; Cella Media 0,096 ± 0,037 cm; Third ventricle ratio 0,040 ± 0,007 cm. Anatomical measures: Fourth ventricle length 0,295 ± 0,073 cm; Fourth ventricle width 0,344 ± 0,074 cm; Left lateral ventricle 4175 ± 0,275 cm; Right lateral ventricle 4182 ± 0,269 cm; Frontal horn length 1795 ± 0,303 cm; Interventricular foramen left 1794 ± 0,301 cm; Interventricular foramen right 1,78 ± 0,317 cm. Conclusions The present study provides baseline values of linear indexes of the ventricles in the ovine models. The acquisition of these data contributes to filling the knowledge void on important anatomical and morphological features of the sheep brain.

Background A balanced anaesthetic protocol is a common concept in modern veterinary anaesthesia and aims to maintain good intraoperative cardiopulmonary function. In horses, alpha-2-agonists produce sedation and analgesia and have been shown to reduce inhalational anaesthetic requirements when administered intravenously. Furthermore, these drugs can improve recovery quality. Preliminary investigations of subcutaneous dexmedetomidine administration in humans demonstrated a reduced haemodynamic impact if compared with the intravenous route suggesting that dexmedetomidine is adequately absorbed with both administration routes. The aim of the study was to compare two different dexmedetomidine (DEX) administration routes: intravenous constant rate infusion (CRI) versus repeated subcutaneous (SC) injections on cardiopulmonary function and recovery in anaesthetized horses. Results No significant differences between groups in heart rate and systolic arterial pressure were detected. A significantly higher mean and diastolic arterial pressure were detected in the SC group at T25 (p = 0.04; p = 0.02), T75 (p = 0.02; p = 0.009), and T85 (p = 0.001; p = 0.005). In SC group there was a significantly lower dobutamine infusion rate (p = 0.03) and a significantly higher urinary output (p = 0.02). Moreover, recovery quality was higher (p = 0.01). Conclusions Cardiopulmonary effects in both groups were comparable and within clinical ranges with less dobutamine requirement in the subcutaneous group. Recovery was of better quality with fewer attempts in horses receiving subcutaneous dexmedetomidine. The present study suggests that intravenous constant rate infusion and subcutaneous repeated administration of dexmedetomidine at indicated dosage can be useful in balanced anaesthesia without any systemic or local adverse effects; moreover, in healthy horses undergoing general anaesthesia, repeated subcutaneous dexmedetomidine administration may be a suitable alternative if constant rate infusion is not feasible.

Cartilage grafting is a common procedure in nasal reconstruction or dorsal augmentation. Costal cartilage is usually preferred to conchal or septal cartilage when a larger amount of graft is required, although this cartilage type is often complicated by postoperative warping. To overcome this complication, we suggest the use of multilayer costal grafts. This study aims to compare single-layer and multilayer costal grafts concerning angle of warpage, cartilage viability, and architectural changes in the animal model. Twelve costal grafts were harvested from a fresh Landrace pig cadaver; six were shaped in single-layer grafts and six into a multilayer structure, both having the same thickness. These grafts were implanted in subcutaneous dorsal skin pockets of six athymic nude rats. After 8 weeks, the animals were euthanized and the grafts removed. Pictures of the cartilages were acquired. The samples were processed and stained for histological (hematoxylin and eosin, Alcian blue, Von Kossa, Masson-Goldner trichrome, and Verhoeff/Van Gieson stains) and immunohistochemical (GFAP) analyses. A higher grade of deformation was observed in the single-layer group compared to the multilayer one (5.2° vs 0.3°). Multilayer cartilage showed significantly higher chondrocyte density (70.4 vs 44.9 cells per field at 40×) and the lowest loss of nuclei in chondrocyte lacunae percentage (0.03 vs 3.2 %). Single-layer grafts also showed sporadic inflammatory cell infiltration, not found in multilayer ones. Multilayer grafts showed a decreased degree of warping as well as an increased viability and should be considered as a valuable alternative in nasal reconstruction. Level of evidence: Not ratable

Plantar reconstruction is often challenging for plastic surgeons because of the peculiar anatomical features of this region. A large variety of reconstructive techniques for the plantar aspect of the foot have been described previously, including skin grafts, local flaps, fasciocutaneous flaps, perforator flaps, cross-limb flaps, and free flaps. This article presents a case of a 64-year-old patient with insulin-dependent diabetes who was involved in a traffic accident that resulted in a large plantar tissue defect (9×4 cm) extending to the base of the toes. After debridement of the wound, a subcutaneous flap was raised from the medial aspect of the lower leg in a sovrafascial plane. The flap was based on a double vascularization given by the great saphenous vein and by the perforator vessels from the posterior tibial artery, located anteriorly and inferiorly to the medial malleolus. The flap showed excellent vitality and long-term result with reduced donor site morbidity. We believe this flap represents a reliable surgical option in superficial plantar defects due to easy harvesting, short operative time, and minimal donor site morbidity. The subcutaneous flap of the distal medial fourth of the leg is a safe technique because of the vascular components of the pedicle. It provides durable coverage, mechanical resistance to pressure and shear stresses and, in selected cases (superficial defects, thin patients), is an interesting option to avoid major free flap procedures.

Even if anesthetics are widely used in the medical practice, there are still many unresolved issues relating to their mechanism(s) of action on neuronal circuits. Since their action is likely to be synaptic, these compounds could act either presynaptically, with a modification of neurotransmitter release and/or reuptake machineries, or postsynaptically, with alterations of the number and/or sensitivity of post-synaptic receptors. Despite the complexity of these molecular targets, all general anesthetics induce a profound inhibition of cortical EEG activity while sparing evoked cortical responses. Based on these considerations, we began the investigation of the electrophysiological action of various classes of general anesthetics on the activity of the rat visual system to identify potential targets and uncover specific features of their action. We compared the effects of three states of anesthesia induced by two different anesthetic molecules (sevoflurane and propofol). During experiments, adult rats were kept at 37°C, curarized, mechanically ventilated and oxygen and CO2 levels were continuously monitored. Rats were exposed to monocular light pulses of different durations and intensities and EEG activity and evoked potentials, both ON and OFF responses, were recorded using implanted superficial electrodes. While basal cortical activity is reduced in a comparable manner by both classes of anesthetics, throughout the three states of anesthesia, the effect on visual evoked activity exhibit clear differences, suggesting the presence of two very distinct circuital mechanisms of action. In future, the analysis on the response of visual cortex, might provide important informations on the mode of action of general anesthetics.

An 8-year-old male lion with progressive lack of secondary sex characteristics, dysorexia and weight loss was referred to our Institution. The patient was anaesthetized to undergo general clinical evaluation, hematologic, serum biochemical and hormonal profile, FIV/FeLV tests. Total body computed tomography, abdominal ultrasonography and fine-needle aspirates of the liver and left adrenal lesion were performed. Imaging findings showed the presence of a neoplastic lesion on the left adrenal gland and generalized hepatopathy. Blood tests reported an estradiol concentration of 462 ng/dl. To our knowledge, this is the first description of an adrenal mass in a lion associated with secondary feminization.

Prosthetic exposure is a severe complication of total knee arthroplasty. Many factors are responsible for failed wound healing, and successful salvage of total knee arthroplasty requires early identification of infection, antecedent events related with wound healing failure, aggressive surgical debridement and early appropriate soft-tissue coverage with local skin, fasciocutaneous, muscle, neurocutaneous or perforator flaps. In this report, we present 15 cases of exposed knee prosthesis treated with island sural neurocutaneous flap. Follow-up showed favorable clinical outcomes: all flaps survived and only two cases of hematoma and one of aseptic phystula occurred. According to our results, the island neurofasciocutaneous sural flap represents a sensate reconstructive alternative for providing fine and dependable soft tissue for covering skin defects around the knee.

info:eu-repo/semantics/published