Investigation of muscarinic and metabotropic (glutamate) response properties of adult and immature olfactory cortical brain slices in vitro.

Muscarinic cholinergic- and metabotropic glutamate receptor-evoked responses of adult and immature olfactory cortical neurones were studied in brain slices using intracellular electrophysiological recordings. An attempt was made to study the ontogeny of the cortical slow post-stimulus afterdepolarization (sADP) induced by muscarinic cholinergic or metabotropic glutamate agonists in immature (14-22 days) and adult (greater than 40 day old) rats. In adult neurones, 10 μM oxotremorine-M (OXO-M, a muscarinic agonist) or 1S,3R- ACPD (10-50 μM, a metabotropic glutamate receptor agonist) displayed postsynaptic excitatory and presynaptic inhibitory effects. In contrast, immature rat olfactory neurones responded to 10 μM OXO-M with spontaneous epileptiform activity which was blocked by pharmacological agents such as atropine (1 μM), pirenzepine (a muscarinic M1 receptor antagonist; 300 nM), tetrodotoxin (1 μM) or the glutamate receptor antagonists DL-APV (100 μM) or CNQX (20 μM). Inhibition of either GABAA or GABAB receptor activity with bicuculline (10 μM) or CGP52432 (1 μM) respectively, actively promoted bursting behaviour, working synergistically with lower doses of OXO-M. Conversely, augmenting GABAA or GABAB receptor function with pentobarbitone (100 μM) or baclofen (10 μM), respectively, blocked the bursting. The induced bursting was accompanied by a dramatic prolongation of evoked postsynaptic potentials (PSPs), exhibiting recurrent superimposed spike discharges, not seen in control. 1S,3R-ACPD (10-50 μM) induced typical adult-type responses in immature cells, i.e. presynaptic inhibition and postsynaptic excitation, with no evidence of epileptiform behaviour. During experiments designed to investigate the possible involvement of release of calcium from intracellular stores in the generation of the cholinergic/metabotropic glutamate agonist-induced sADP and its underlying tail current (IADP) adult guinea- pig olfactory neurones, it was found that the sADP induced by OXO-M (10 μM) or 1S,3R ACPD (10-50 μM), could be reversibly blocked by 0.5-3 mM caffeine, a compound known to promote release of calcium from intracellular stores. However, when this inhibitory action was investigated further using compounds with more specific effects on intracellular calcium release, i.e. ryanodine (10 μM), thapsigargin (3 μM) or dantrolene (10 μM), no consistent inhibition of IADP was observed. In addition, other possible effects of caffeine were discounted as being important by use of more specific pharmacological tools, i.e. IBMX (100 μM; an inhibitor of phosphodiesterase activity) or adenosine (100 μM; to reverse any inhibition of adenosine receptors imposed by caffeine). In caesium-loaded cells, a direct block of voltage-sensitive calcium entry by 3 mM caffeine was found, but this could not account for the full inhibition of IADP in this system; a direct blockade of the proposed IADP K+ channels by caffeine was therefore proposed. In conclusion, the muscarinic response profile of immature rat olfactory neurones was found to differ from adult neurones, since they displayed bursting behaviour in response to muscarinic (but not metabotropic) activation, thought to be generated through a local network mechanism. Furthermore, release of calcium from intracellular stores was unlikely to play an important role in sADP or IADP generation. Caffeine, a known modulator of intracellular calcium release, however, blocked IADP through a mechanism which did not involve intracellular calcium stores, most likely having a direct action on calcium entry and/or the proposed IADP K+ conductance

Do Playgrounds Help Develop Children’s Fundamental Movement Skills? Using Direct Video Observations to Investigate

Playgrounds are global environments that are purpose made for children and can offer a variety of opportunities for children to be physically active and practice their fundamental movement skills (FMS), which can lead to future physical activity and sport participation. Previous research highlighted that children engage in different types of physical activity (PA) depending on playgrounds apparatus and area. However, there is a paucity of research that investigates the link between playground features, structures, PA, and FMS. This study sought to assess the impact of different playgrounds on PA type PA intensity and the types of FMS completed. This observational study examined 29 (M = 10, F = 19) children’s behaviours on three different playgrounds. Video cameras were placed strategically across the three playgrounds to allow for footage to be captured and analysed using the Observational System for Recording Physical Activity in Children (OSRAC). One-way ANOVA was used to examine the different OSRAC categories across the three playgrounds. Climbing equipment (average 1217.10 s) was the frequently used type of apparatus, standing was the most commonly performed type of activity (average 377.60 s) and stationary movements whilst moving limbs were the most regularly (average 605.13 s) performed type of PA intensity. There were no instances of any throwing, catching, or kicking activities performed across the three playgrounds. Results suggest that public playgrounds do not facilitate more intense types of PA, nor object control skills due to a lack of suitable equipment

Wide-band information transmission at the calyx of Held

We use a mathematical model of the calyx of Held to explore information transmission at this giant glutamatergic synapse. The significant depression of the postsynaptic response to repeated stimulation in vitro is a result of various activity-dependent processes in multiple time scales, which can be reproduced by multiexponential functions in this model. When stimulated by Poisson-distributed spike trains the amplitude of the postsynaptic current varies considerably with the preceding interspike intervals. Here we quantify the information contained in the postsynaptic current amplitude about preceding interspike intervals and determine the impact of different pre- and postsynaptic factors on information transmission. The mutual information between presynaptic spike times and the amplitude of the postsynaptic response in general decreases as the mean stimulation rate increases, but remains high even at frequencies greater than 100 Hz, unlike at many neocortical synapses. The maintenance of information transmission is attributable largely to vesicle recycling rates at low frequencies of stimulation, shifting to vesicle release probability at high frequencies. Also at higher frequencies the synapse operates largely in a release ready mode in which most release sites contain a release-ready vesicle and release probabilities are low

Scaling Success: Parental Perceptions of the Benefits of a 20-week Football Living-Lab Approach for Children Living with Cerebral Palsy

BackgroundLiving-lab approaches have effectively connected academic research with community needs but have not yet been applied to promote physical activity for children with cerebral palsy (CP). This study evaluated a 20-week football-based living-lab programme for children aged 5–10 years with CP, grounded in the principles of Football is Medicine and physical literacy.Methods A qualitative design was employed, involving seven one-to-one semistructured interviews with parents or legal guardians of programme participants. A deductive thematic analysis was conducted, and pen profile diagrams were developed to represent key themes related to physical literacy outcomes.Results Parents reported benefits across multiple dimensions of their children’s physical literacy, including improved competence, confidence, motivation and enjoyment. All parents observed enhanced social interaction. Six described the sessions as inclusive and community-oriented, while five felt the programme was personalised to their child’s needs. Three parents perceived the football activities as complementary to physical therapy, supporting physical rehabilitation. Participation also enabled parents to exchange strategies and engage more meaningfully in their child’s well-being.Conclusion The football-based living-lab supported the holistic development of children with CP, enhancing physical, psychological and social domains of physical literacy. Parental involvement further reinforced perceived therapeutic and community benefits

A biophysical model of short-term plasticity at the calyx of Held

The calyx of Held is a giant glutamatergic synapse in the auditory system and displays multiple forms of short-term facilitation and depression. This study presents a detailed model of short-term plasticity at this synapse. The main components of the model are the presynaptic vesicle dynamics, which include passive and activity-dependent recycling, calcium-dependent exocytosis and the postsynaptic AMPA receptor kinetics. The behaviour of the model is compared to experimental data and reproduces the time course and amplitude of synaptic depression during repetitive stimulation at different frequencies. A comparison of different manipulations of the model shows that accurate fits require the inclusion of fast activity-dependent vesicle recycling and a limited number of vesicle docking sites at each active zone

Bovine pericardium based non-cross linked collagen matrix for successful root coverage, a clinical study in human

Introduction: The aim of this study was to clinically assess the capacity of a novel bovine pericardium based, non-cross linked collagen matrix in root coverage. Methods: 62 gingival recessions of Miller class I or II were treated. The matrix was adapted underneath a coronal repositioned split thickness flap. Clinical values were assessed at baseline and after six months. Results: The mean recession in each patient was 2.2 mm at baseline. 6 Months after surgery 86.7% of the exposed root surfaces were covered. On average 0,3 mm of recession remained. The clinical attachment level changed from 3.5 ± 1.3 mm to 1,8 ( ± 0,7) mm during the observational time period. No statistically significant difference was found in the difference of probing depth. An increase in the width of gingiva was significant. With a baseline value of 1.5 ± 0.9 mm an improvement of 2.4 ± 0.8 mm after six month could be observed. 40 out of 62 recessions were considered a thin biotype at baseline. After 6 months all 62 sites were assessed thick. Conclusions: The results demonstrate the capacity of the bovine pericardium based non-cross linked collagen matrix for successful root coverage. This material was able to enhance gingival thickness and the width of keratinized gingiva. The percentage of root coverage achieved thereby is comparable to existing techniques. This method might contribute to an increase of patient's comfort and an enhanced aesthetical outcome

Altered monocyte and fibrocyte phenotype and function in scleroderma interstitial lung disease: reversal by caveolin-1 scaffolding domain peptide

Interstitial lung disease (ILD) is a major cause of morbidity and mortality in scleroderma (systemic sclerosis, or SSc). Fibrocytes are a monocyte-derived cell population implicated in the pathogenesis of fibrosing disorders. Given the recently recognized importance of caveolin-1 in regulating function and signaling in SSc monocytes, in the present study we examined the role of caveolin-1 in the migration and/or trafficking and phenotype of monocytes and fibrocytes in fibrotic lung disease in human patients and an animal model. These studies fill a gap in our understanding of how monocytes and fibrocytes contribute to SSc-ILD pathology. We found that C-X-C chemokine receptor type 4-positive (CXCR4+)/collagen I-positive (ColI+), CD34+/ColI+ and CD45+/ColI+ cells are present in SSc-ILD lungs, but not in control lungs, with CXCR4+ cells being most prevalent. Expression of CXCR4 and its ligand, stromal cell-derived factor 1 (CXCL12), are also highly upregulated in SSc-ILD lung tissue. SSc monocytes, which lack caveolin-1 and therefore overexpress CXCR4, exhibit almost sevenfold increased migration toward CXCL12 compared to control monocytes. Restoration of caveolin-1 function by administering the caveolin scaffolding domain (CSD) peptide reverses this hypermigration. Similarly, transforming growth factor β-treated normal monocytes lose caveolin-1, overexpress CXCR4 and exhibit 15-fold increased monocyte migration that is CSD peptide-sensitive. SSc monocytes exhibit a different phenotype than normal monocytes, expressing high levels of ColI, CD14 and CD34. Because ColI+/CD14+ cells are prevalent in SSc blood, we looked for such cells in lung tissue and confirmed their presence in SSc-ILD lungs but not in normal lungs. Finally, in the bleomycin model of lung fibrosis, we show that CSD peptide diminishes fibrocyte accumulation in the lungs. Our results suggest that low caveolin-1 in SSc monocytes contributes to ILD via effects on cell migration and phenotype and that the hyperaccumulation of fibrocytes in SSc-ILD may result from the altered phenotype and migratory activity of their monocyte precursors

Requirement of Podocalyxin in TGF-Beta Induced Epithelial Mesenchymal Transition

Epithelial mesenchymal transition (EMT) is characterized by the development of mesenchymal properties such as a fibroblast-like morphology with altered cytoskeletal organization and enhanced migratory potential. We report that the expression of podocalyxin (PODXL), a member of the CD34 family, is markedly increased during TGF-β induced EMT. PODXL is enriched on the leading edges of migrating A549 cells. Silencing of podocalyxin expression reduced cell ruffle formation, spreading, migration and affected the expression patterns of several proteins that normally change during EMT (e.g., vimentin, E-cadherin). Cytoskeletion assembly in EMT was also found to be dependent on the production of podocalyin. Compositional analysis of podocalyxin containing immunoprecipitates revealed that collagen type 1 was consistently associated with these isolates. Collagen type 1 was also found to co-localize with podocalyxin on the leading edges of migrating cells. The interactions with collagen may be a critical aspect of podocalyxin function. Podocalyxin is an important regulator of the EMT like process as it regulates the loss of epithelial features and the acquisition of a motile phenotype