Cerebellar-dependent delay eyeblink conditioning in adolescents with Specific Language Impairment

Cerebellar impairments have been hypothesized as part of the pathogenesis of Specific Language Impairment (SLI), although direct evidence of cerebellar involvement is sparse. Eyeblink Conditioning (EBC) is a learning task with well documented cerebellar pathways. This is the first study of EBC in affected adolescents and controls. 16 adolescent controls, 15 adolescents with SLI, and 12 adult controls participated in a delay EBC task. Affected children had low general language performance, grammatical deficits but no speech impairments. The affected group did not differ from the control adolescent or control adult group, showing intact cerebellar functioning on the EBC task. This study did not support cerebellar impairment at the level of basic learning pathways as part of the pathogenesis of SLI. Outcomes do not rule out cerebellar influences on speech impairment, or possible other forms of cerebellar functioning as contributing to SLI

Role of the Striatum and the Cerebellum in Motor Skill Acquisition

Motor skill acquisition was investigated in patients with Parkinson's disease (PD) or cerebellar dysfunction using two sensory-guided tracking tasks. The subjects had to learn to track a visual target (a square) on a computer screen by moving a joystick under two different conditions. In the unreversed task, the horizontal target movements were semi-predictable and could be anticipated. In the reversed task, the horizontal movements of a pointer which had to be kept within the target square were mirror-reversed to the joystick movements. PD patients showed intact learning of the semi-predictable task and reduced learning of the mirror-reversed task; patients with cerebellar dysfunction showed the opposite pattern. These findings are discussed in relation to the differential contribution of the cerebellum and the striatum to motor skill acquisition: the cerebellum appears to participate in the implementation of anticipatory movements, whereas the striatum may be critically involved in types of motor learning which require a high degree of internal elaboration

In vitro and in vivo analysis of macroporous biodegradable poly(D,L-lactide-co-glycolide) scaffolds containing bioactive glass

Recent studies have demonstrated the angiogenic potential of 45S5 Bioglass (R). However, it is not known whether the angiogenic properties of Bioglass (R) remain when the bioactive glass particles are incorporated into polymer composites. The objectives of the current study were to investigate the angiogenic properties of 45S5 Bioglass (R) particles incorporated into biodegradable polymer composites. In vitro studies demonstrated that fibroblasts Cultured on discs consisting of specific quantities of Bioglass (R) particles mixed into poly(D,L-lactide-co-glycolide) secreted significantly increased quantities of vascular endothelial growth factor. The optimal quantity of Bioglass (R) particles determined from the in vitro experiments was incorporated into three-dimensional macroporous poly(D,L-lactide-co-glycolide) foam scaffolds. The foam scaffolds were fabricated using either compression molding or thermally induced phase separation processes. The foams were implanted subcutaneously into mice for periods Of Lip to 6 weeks. Histological assessment was used to determine the area of granulation tissue around the foams, and the number of blood vessels within the granulation tissue was counted. The presence of Bioglass (R) particles in the foams produced a sustained increase in the area of granulation tissue surrounding the foams. The number of blood vessels surrounding the neat foams was reduced after 2 weeks of implantation; however, compression-molded foams containing Bioglass (R) after 4 and 6 weeks of implantation had significant]), more blood vessels surrounding the foams compared with foams containing no Bioglass (R) at the same time points. These results indicate that composite polymer foam scaffolds containing Bioglass (R) particles retain granulation tissue and blood vessels surrounding the implanted foams. The use of this polymer composite for tissue engineering scaffolds might provide a novel approach for ensuring adequate vascular Supply to the implanted device

Development and characterization of a novel bioresorbable and bioactive biomaterial based on polyvinyl acetate, calcium carbonate and coralline hydroxyapatite

Coralina® HAP-200 (coralline hydroxyapatite obtained by hydrothermal treatment of marine corals) and POVIAC® (polymeric matrix based on PVAc), commercial trade marks were mixed with a natural product from the Cuban sea costs, i.e. calcium carbonate from Porites Porites coral, to obtain a novel bioactive composite with potential use as bone restoration material. The samples were characterized by physical-chemical (FTIR, XRD, SEM, EDS) and mechanical studies. It was shown that there is no chemical interaction between the inorganic filler and the polymer matrix, each conserving the original properties of the raw materials. The studied formulation had a compressive strength similar to that reported for trabecular bone. Scanning electron microscopy examination revealed that the addition of CaCO3 induces a change on the morphologic structure of the composite obtained after 30 days of SBF immersion. These composites generate novel biomaterials capable of promoting the deposition of a new phase, a Ca-P layer due to the bioactivity of a Ca2+ precursors