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Osseointegration of metallic implants used in orthopedic surgery requires that osteoprogenitor cells attach and adhere to the surface, then proliferate, differentiate into osteoblasts, and finally produce mineralized matrix. Because the ability of progenitor cells to attach to a scaffold surface during early stages is important in the development of new tissue structures, we developed in our laboratory, a strategy involving grafting of implants with a polymer of sodium styrene sulfonate (polyNaSS) used as a scaffold which enables human mesenchymal stem cells (hMSCs) interactions. In the present study, we investigated the cellular response of hMSCs to polyNaSS surfaces of titanium (Ti). In particular, cell proliferation, cell viability, cell differentiation, and cell spreading were evaluated. Results showed that cell proliferation and cell viability did not differ with any statistical significance between modified and unmodified Ti surfaces. Interestingly, culture of MSCs on polyNaSS surfaces resulted in a significant increase of cell spreading and cell differentiation compared with the other tested surfaces. These results suggest that titanium surface grafted with polyNaSS is a suitable scaffold for bone tissue engineering. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013. [ABSTRACT FROM AUTHOR]

Severe burns remain a life-threatening local and general inflammatory condition often with serious sequelae, despite remarkable progress in their treatment over the past three decades. Cultured epidermal autografts, the first and still most up-to-date cell therapy for burns, plays a key role in that progress, but drawbacks to this need to be reduced by using cultured dermal-epidermal substitutes. This review focuses on what could be, in our view, the next major breakthrough in cell therapy of burns - use of mesenchymal stromal cells (MSCs). After summarizing current knowledge, including our own clinical experience with MSCs in the pioneering field of cell therapy of radiation-induced burns, we discuss the strong rationale supporting potential interest in MSCs in treatment of thermal burns, including limited but promising pre-clinical and clinical data in wound healing and acute inflammatory conditions other than burns. Practical options for future therapeutic applications of MSCs for burns treatment, are finally considered. [ABSTRACT FROM AUTHOR]

We have investigated whether the phenotype of myogenic clones derived from satellite cells of different muscles from the transgenic immortomouse depended on muscle type origin. Clones derived from neonatal, or 6- to 12-week-old fast and slow muscles, were analyzed for myosin and enolase isoforms as phenotypic markers. All clones derived from slow-oxidative muscles differentiated into myotubes with a preferentially slow contractile phenotype, whereas some clones derived from rapid-glycolytic or neonatal muscles expressed both fast and slow myosin isoforms. Thus, muscle origin appears to bias myosin isoform expression in myotubes. The neonatal clone (WTt) was cultivated in various medium and substrate conditions, allowing us to determine optimized conditions for their differentiation. Matrigel allowed expressions of adult myosin isoforms, and an isozymic switch from embryonic α- toward muscle-specific β-enolase, never previously observed in vitro. These cells will be a useful model for in vitro studies of muscle fiber maturation and plasticity. Developmental Dynamics 237:1412-1423, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

An important issue in the field of clinical and developmental psychopathology is whether cognitive control processes, such as response inhibition, can be specifically enhanced by motivation. To determine whether non-social (i.e. monetary) and social (i.e. positive facial expressions) rewards are able to differentially improve response inhibition accuracy in typically developing children and adolescents, an 'incentive' go/no-go task was applied with reward contingencies for successful inhibition. In addition, the impact of children's personality traits (such as reward seeking and empathy) on monetary and social reward responsiveness was assessed in 65 boys, ages 8 to 12 years. All subjects were tested twice: At baseline, inhibitory control was assessed without reward, and then subjects were pseudorandomly assigned to one of four experimental conditions, including (1) social reward only, (2) monetary reward only, (3) mixed social and monetary reward, or (4) a retest condition without reward. Both social and non-social reward significantly improved task performance, although larger effects were observed for monetary reward. The higher the children scored on reward seeking scales, the larger was their improvement in response inhibition, but only if monetary reward was used. In addition, there was a tendency for an association between empathic skills and benefits from social reward. These data suggest that social incentives do not have an equally strong reinforcing value as compared to financial incentives. However, different personality traits seem to determine to what extent a child profits from different types of reward. Clinical implications regarding probable hyposensitivity to social reward in subjects with autism and dysregulated reward-seeking behaviour in children with attention-deficit/hyperactivity disorder (ADHD) are discussed.