Maria Rita Stornelli

Isolation and expansion of equine umbilical cord-derived matrix cells (EUCMCs)

Stem cells from extra‐embryonic sources can be obtained by non‐invasive procedures. We have standardized a method for the expansion of equine umbilical cord‐derived matrix cells (EUCMCs) for potential therapy.

Different media and supplements modulate the clonogenic and expansion properties of rabbit bone marrow mesenchymal stem cells

Background -Rabbits provide an excellent model for many animal and human diseases, such as cardiovascular diseases, for the development of new vaccines in wound healing management and in the field of tissue engineering of tendon, cartilage, bone and skin.The study presented herein aims to investigate the biological properties of bone marrow rabbit MSCs cultured in different conditions, in order to provide a basis for their clinical applications in veterinary medicine.Findings -MSCs were isolated from 5 New Zealand rabbits. Fold increase, CFU number, doubling time, differentiation ability and immunophenotype were analyzed.With the plating density of 10 cells/cm2 the fold increase was significantly lower with DMEM-20%FCS and MSCs growth was significantly higher with αMEM-hEGF. The highest clonogenic ability was found at 100 cell/cm2 with MSCBM and at 10 cell/cm2 with M199. Both at 10 and 100 cells/cm2, in αMEM medium, the highest CFU increase was obtained by adding bFGF. Supplementing culture media with 10%FCS-10%HS determined a significant increase of CFU.Conclusion -Our data suggest that different progenitor cells with differential sensitivity to media, sera and growth factors exist and the choice of culture conditions has to be carefully considered for MSC management.

Isolation and characterization of equine amnion mesenchymal stem cells

The amnion is a particular tissue whose cells show features of multipotent stem cells proposed for use in cellular therapy and regenerative medicine. From equine amnion collected after the foal birth we have isolated MSCs (mesenchymal stem cells), namely EAMSCs (equine amnion mesenchymal stem cells), from the mesoblastic layer. The cells were grown in α-MEM (α-modified minimum essential medium) and the effect of EGF (epidermal growth factor) supplementation was evaluated. To assess the growth kinetic of EAMSCs we have taken into account some parameters [PD (population doubling), fold increase and DT (doubling time)]. The differentiation in chondrogenic, adipogenic and osteogenic types of cells and their epitope expression by a cytofluorimetric study have been reported. EGF supplementation of the culture medium resulted in a significant increase in PD growth parameter and in the formation of bone nodules for the osteogenic differentiation. By immunohistochemistry the amnion tissue shows a positivity for the c-Kit (cluster tyrosine-protein kinase), CD105 and Oct-4 (octamer-binding transcription factor 4) antigens that confirmed the presence of MSCs with embryonic phenotype.

Tailored star poly (ε-caprolactone) wet-spun scaffolds for in vivo regeneration of long bone critical size defects:

One of the most challenging requirements of a successful bone tissue engineering approach is the development of scaffolds specifically tailored to individual tissue defects. Besides materials chemistry, well-defined scaffold’s structural features at the micro- and macro-levels are needed for optimal bone in-growth. In this study, polymeric fibrous scaffolds with a controlled internal network of pores and modelled on the anatomical shape and dimensions of a critical size bone defect in a rabbit’s radius model were developed by employing a computer-aided wet-spinning technique. The tailored scaffolds made of star poly(ε-caprolactone) or star poly(ε-caprolactone)–hydroxyapatite composite material were implanted into 20-mm segmental defects created in radial diaphysis of New Zealand white rabbits. Bone regeneration and tissue response were assessed by X-rays and histological analysis at 4, 8 and 12 weeks after surgery. No signs of macroscopic and microscopic inflammatory reactions were detected, and the developed scaffolds showed a good ability to support and promote the bone regeneration process. However, no significant differences in osteoconductivity were observed between star poly(ε-caprolactone) and star poly(ε-caprolactone)–hydroxyapatite scaffolds. Long-term study on implanted star poly(ε-caprolactone) scaffolds confirmed the presence of signs of bone regeneration and remodelling, particularly evident at 24 weeks.

A unified approach to model peripheral nerves across different animal species

Peripheral nerves are extremely complex biological structures. The knowledge of their response to stretch is crucial to better understand physiological and pathological states (e.g., due to overstretch). Since their mechanical response is deterministically related to the nature of the external stimuli, theoretical and computational tools were used to investigate their behaviour. In this work, a Yeoh-like polynomial strain energy function was used to reproduce the response of in vitro porcine nerve. Moreover, this approach was applied to different nervous structures coming from different animal species (rabbit, lobster, Aplysia) and tested for different amount of stretch (up to extreme ones). Starting from this theoretical background, in silico models of both porcine nerves and cerebro-abdominal connective of Aplysia were built to reproduce experimental data (R2 > 0.9). Finally, bi-dimensional in silico models were provided to reduce computational time of more than 90% with respect to the performances of fully three-dimensional models.

Preferential epithelial expression of type-1 cannabinoid receptor (CB1R) in the developing canine embryo

The use of cannabinoid receptor agonists is gaining a strong interest both in human and veterinary medicine. The potential use of cannabimimetic compounds in companion animals was reviewed in 2007 for their role in tissue inflammation and pain. A better knowledge of type-1 cannabinoid receptor (CB1R) expression on the target population may help in risk management in order to prevent unwanted side effects. We used 30-days old canine embryos to describe the distribution of CB1R by means of immunohistochemistry with a commercially available antibody.CB1R immunoreactivity was mainly epithelial and included most structures of central and peripheral nervous system, inner ear, olfactory epithelium and related structures, eye and thyroid. Further investigative research on the role of the endocannabinoid system in the developmental biology field is needed, however, we show that in the canine species we must consider pregnancy as risk condition for developmental abnormalities that may arise upon the use of CB1R receptor agonists.

Glucagon-like peptide 1 (GLP-1) in the gastrointestinal tract of the pheasant (Phasianus colchicus)

The distribution of Glucagon-like peptide 1 (GLP-1) was investigated in the gastrointestinal tract of the pheasant using immunohistochemistry. GLP-1 immunoreactive cells were common in the small intestine, in the proventriculus and in the pancreas. Immunostained cells were not seen in the crop, in the gizzard and in the large intestine. Double labelling demonstrated that GLP-1 and pituitary adenylate cyclase-activating polypeptide (PACAP) were occasionally co-localized only in the duodenal villi. In contrast to what was previously described in the chicken and ostrich, we noted GLP-1 positive cells in the duodenum. These data were consistent with the presence of proglucagon mRNA in the chicken duodenum. Our findings indicate that GLP-1 might have an inhibitory effect on gastric and crop emptying and on acid secretion also in the pheasant. Moreover, the results of the present research regarding the initial region of the small intestine suggest a further direct mechanism of the GLP-1 release during the early digestion phase and an enhancement of its incretin role.

Fast in silico assessment of physical stress for peripheral nerves

AbstractThe level of physical stress rules the adaptative response of peripheral nerves, which is crucial to assess their physiological and pathological states. To this aim, in this work, different computational approaches were presented to model the stress response of in vitro peripheral nerves undergoing longitudinal stretch. More specifically, the effects of geometrical simplifications were studied with respect to the amount of computational time needed to obtain relevant information. Similarly, the variation of compressibility of the peripheral nervous tissue was investigated with respect to the variation of longitudinal stress and transversal stretch variations, and with reference to the computational time needed for simulations. Finally, the effect of small dimensional changes was investigated to better understand whether the variation of time was only due to the amount of nodes or elements. In conclusion, since fast in silico models, able to assess the nerve stress, could be a strategic advantage in case of time constraints or on-line evaluation (e.g., surgical interventions), a synergistic use of these approaches was proposed as a possible strategy to decrease the computational time needed for simulations from minutes to seconds. Graphical AbstractA synergistic approach involving both symmetry and tuning of compressibility allows the computational time to be considerably decreased

Morphological study of the iris musculature in diurnal and nocturnal raptors

En la literatura, se establece que la musculatura del iris se compone de fibras musculares estriadas en las aves, mientras que en los mamiferos, la forman los musculos lisos. Algunos autores informan tambien de la presencia de tejido muscular liso en el iris de algunas especies de aves. El presente estudio informa sobre los tejidos musculares del iris (tipo de tejido, la direccion y diametro de las fibras musculares o celulas) en cinco especies de Accipitriformes y cuatro especies de Strigiformes que muestran diferentes habitos en funcion de su comportamiento depredador. Este estudio morfologico se realizo en aves rapaces que murieron o fueron eutanasiadas en el Centro de Vida Salvaje de Rescate de Aves Marinas y Acuaticas de Livorno (Italia). El examen histologico de secciones seriadas radiales del iris mostro la presencia tanto de musculatura estriada como lisa, aunque con marcadas diferencias entre las especies analizadas, pero sin correlacion directa con el estilo de vida diurna o nocturna. Las fibras estriadas estuvieron siempre presentes, principalmente en direccion transversal a lo largo del estroma del iris, mientras que las diferencias histologicas fueron de las celulas lisas. Tanto el aguilucho y el gavilan (Accipitriformes) como el buho real y el mochuelo (Strigiformes) mostraron una capa compacta de celulas musculares lisas transversales en todo el estroma del iris. En las otras especies analizadas, las celulas musculares lisas fueron ligeramente detectables de manera dispersa o no detectables. Dado que el tejido del musculo liso transversal permite mantener un estado miotico durante largos periodos de tiempo, nuestros resultados podrian estar mas correlacionados con el comportamiento depredador, y no con el orden taxonomico.

A Hybrid Framework to Investigate Physical Stress Evolution in Peripheral Nerves

The level of physical stress rules the adaptative response of peripheral nerves, which is crucial to assess their physiological and pathological states. To this aim, in this work, a hybrid computational approach was presented to model the stress response of in vitro peripheral nerves undergoing longitudinal stretch. In addition, the rate of change of stiffness with strain was investigated and quantified through the secant modulus in order to achieve a quantitative framework, providing crucial information for both physical rehabilitation and biomaterial science.