No abstract

Mesenchymal stem cells have a great potential for application in cell based therapies, such as tissue engineering. Adipose derived stem cells have shown the capacity to differentiate into several lineages, and have been isolated in many animal species. Dog is a very relevant animal model to study several human diseases and simultaneously an important subject in veterinary medicine. Thus, in this study we assessed the potential of canine adipose tissue derived stem cells (cASCs) to differentiate into the osteogenic and chondrogenic lineages by performing specific histological stainings, and studied the cell passaging effect on the cASCs stemness and osteogenic potential. We also evaluated the effect of the anatomical origin of the adipose tissue, namely from abdominal subcutaneous layer and from greater omentum. The stemness and osteogenic differentiation was followed by real time RT-PCR analysis of typical markers of mesenchymal stem cells (MSCs) and osteoblasts. The results obtained revealed that cASCs exhibit a progressively decreased expression of the MSCs markers along passages and also a decreased osteogenic differentiation potential. In the author's knowledge, this work presents the first data about the MSCs markers profile and osteogenic potential of cASCs along cellular expansion. Moreover, the obtained data showed that the anatomical origin of the adipose tissue has an evident effect in the differentiation potential of the ASCs. Due to the observed resemblances with the human ASCs, we conclude that canine ASCs can be used as a model cells in tissue engineering research envisioning human applications.

Human and canine periodontium are often affected by an inflammatory pathology called periodontitis, which is associated with severe damages across tissues, namely, in the periodontal ligament, cementum, and alveolar bone. However, the therapies used in the routine dental practice, often consisting in a combination of different techniques, do not allow to fully restore the functionality of the periodontium. Tissue Engineering (TE) appears as a valuable alternative approach to regenerate periodontal defects, but for this purpose, it is essential to develop supportive biomaterial and stem cell sourcing/culturing methodologies that address the complexity of the various tissues affected by this condition. The main aim of this work was to study the in vitro functionality of a newly developed double-layer scaffold for periodontal TE. The scaffold design was based on a combination of a three-dimensional (3D) fiber mesh functionalized with silanol groups and a membrane, both made of a blend of starch and poly-ɛ-(caprolactone). Adipose-derived stem cells (canine adipose stem cells [cASCs]) were seeded and cultured onto such scaffolds, and the obtained constructs were evaluated in terms of cellular morphology, metabolic activity, and proliferation. The osteogenic potential of the fiber mesh layer functionalized with silanol groups was further assessed concerning the osteogenic differentiation of the seeded and cultured ASCs. The obtained results showed that the proposed double-layer scaffold supports the proliferation and selectively promotes the osteogenic differentiation of cASCs seeded onto the functionalized mesh. These findings suggest that the 3D structure and asymmetric composition of the scaffold in combination with stem cells may provide the basis for developing alternative therapies to treat periodontal defects more efficiently.

The inefficacy of the currently used therapies in achieving the regeneration ad integrum of the periodontium stimulates the search for alternative approaches, such as tissue-engineering strategies. Therefore, the core objective of this study was to develop a biodegradable double-layer scaffold for periodontal tissue engineering. The design philosophy was based on a double-layered construct obtained from a blend of starch and poly-ε-caprolactone (30:70 wt%; SPCL). A SPCL fibre mesh functionalized with silanol groups to promote osteogenesis was combined with a SPCL solvent casting membrane aiming at acting as a barrier against the migration of gingival epithelium into the periodontal defect. Each layer of the double-layer scaffolds was characterized in terms of morphology, surface chemical composition, degradation behaviour and mechanical properties. Moreover, the behaviour of seeded/cultured canine adipose-derived stem cells (cASCs) was assessed. In general, the developed double-layered scaffolds demonstrated adequate degradation and mechanical behaviour for the target application. Furthermore, the biological assays revealed that both layers of the scaffold allow adhesion and proliferation of the seeded undifferentiated cASCs, and the incorporation of silanol groups into the fibre-mesh layer enhance the expression of a typical osteogenic marker. This study allowed an innovative construct to be developed, combining a three-dimensional (3D) scaffold with osteoconductive properties and with potential to assist periodontal regeneration, carrying new possible solutions to current clinical needs. Copyright © 2013 John Wiley & Sons, Ltd.

Damages in the maxillofacial bones are frequent in humans following trauma, metabolic diseases, neoplasia, or inflammatory processes. Many of the available treatments to regenerate bone are often ineffective. The goal of this work was to assess the in vivo behavior of an innovative double-layered scaffold based on a blend of starch and polycaprolactone (SPCL) that comprises a membrane obtained by solvent casting, which aims to act as a guided tissue regeneration membrane, and a wet-spun fiber mesh (in some cases functionalized with osteoconductive silanol groups) targeting bone regeneration. The behavior of the double layer scaffold, functionalized with silanol groups (SPCL-Si) or without (SPCL), was assessed in a mandibular rodent model and compared to a commercial collagen membrane (positive control) and to empty defects (negative control). After 8 weeks of implantation, the microcomputed tomography and the histomorphometric analysis revealed that the SPCL-Si scaffolds induced significantly higher new bone formation compared to the collagen membrane and to the empty defects, although they had a similar performance when compared to the SPCL scaffolds. ß

OBJECTIVE To determine the prevalence of dental anomalies in brachycephalic cats from various geographic regions and analyze potential relationships with oral disease. DESIGN Prospective multicenter cross-sectional study. ANIMALS 50 purebred Persian (n = 42) and Exotic (8) cats. PROCEDURES Cats were anesthetized, and a complete dental examination, dental charting, 3-view oral photography, and full-mouth dental radiography were performed. RESULTS Malocclusions were observed in 36 (72%) cats. Crowding of the teeth was evident in 28 (56%) cats, with the incisors being most commonly affected. Malpositioned teeth were noted in 32 (64%) cats, with abnormal orientation being the most common anomaly followed by rotation and impaction. Numerical abnormalities were present in 38 (76%) cats, including 6 (12%) with hyperdontia and 32 (64%) with hypodontia. Periodontal disease was reported in 44 (88%) cats, and cats with periodontal disease were older than cats without. Tooth resorption was evident in 35 (70%) cats. Overall, 123 of 1,349 (8.7%) teeth had external inflammatory resorption and 82 (6.1%) had external replacement resorption. The premolar teeth were the teeth most commonly affected with inflammatory resorption, whereas the canine teeth were the teeth most commonly affected with replacement resorption. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that because of their brachycephaly, Persian and Exotic cats have unique oral and dental features that may predispose them to dental disease (eg, tooth resorption and periodontal disease). Knowledge of the particular dental anomalies common in brachycephalic cats could aid in early detection and mitigation of dental disease in these breeds.

The worldwide incidence of bone disorders is raising, mainly due to aging population. The lack of effective treatments is pushing the development of synthetic bone substitutes (SBSs). Most ceramic‐based SBSs commercially available display limited handling properties. Attempting to solve these issues and achieve wider acceptance by the clinicians, granular ceramics have been associated with hydrogels (HGs) to produce injectable/moldable SBSs. Dextrin, a low‐molecular‐weight carbohydrate, was used to develop a fully resorbable and injectable HG. It was first oxidized with sodium periodate and then cross‐linked with adipic acid dihydrazide. The in vivo biocompatibility and safety of the dextrin‐based HG was assessed by subacute systemic toxicity and skin sensitization tests, using rodent models. The results showed that the HG did not induce any systemic toxic effect, skin reaction, or genotoxicity, neither impaired the bone repair/regeneration process. Then, the HG was successfully combined with granular bone substitute, registered as Bonelike (250–500 μm) to obtain a moldable/injectable SBS, which was implanted in tibial fractures in goats for 3 and 6 weeks. The obtained results showed that HG allowed the stabilization of the granules into the defect, ensuring effective handling, and molding properties of the formulation, as well as an efficient cohesion of the granules. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1678–1689, 2019.

This study aimed to perform a morphometric analysis of the skull of the European shorthair cat by using computed tomographic images. Thirty-seven computed tomography (CT) studies of healthy cats’ heads were used for linear measurements and index calculations of the skull and cranium. The following values were determined: skull length = 8.94 ± 0.45 cm, cranial length = 8.21 ± 0.42 cm, nasal length = 0.73 ± 0.17 cm, cranial width = 4.28 ± 0.26 cm, cranial index = 52.18 ± 3.75%, internal height of cranium = 2.88 ± 0.29 cm, external height of cranium = 3.35 ± 0.12 cm, internal length of the cranium = 5.53 ± 0.28 cm, external length of the cranium = 6.32 ± 0.28 cm, internal cranium index = 45.62 ± 4.77%, external cranium index = 53.06 ± 2.07%, internal cranium and skull index = 61.93 ± 2.38%, external cranium and skull index = 70.70 ± 1.72%, width of the foramen magnum = 1.34 ± 0.07 cm, height of the foramen magnum = 1.01 ± 0.09 cm, and foramen magnum index = 75.37 ± 5.76%. It was also found that the population was homogeneous, with the exception of nasal length (NL), and that there was a sexual dimorphism present, with males exhibiting higher dimensions. This work contributed to characterizing the morphometry of the cranium and skull of the domestic cat, a knowledge of utmost importance for the diagnosis and treatment of conditions affecting this complex anatomical region.