Dominant effect of gap junction communication in wound-induced calcium-wave, NFAT activation and wound closure in keratinocytes.

Wounding induces a calcium wave and disrupts the calcium gradient across the epidermis but mechanisms mediating calcium and downstream signalling, and longer-term wound healing responses are incompletely understood. As expected, live-cell confocal imaging of Fluo-4-loaded normal human keratinocytes showed an immediate increase in [Ca2+ ]i at the wound edge that spread as a calcium wave (8.3 µm/s) away from the wound edge with gradually diminishing rate of rise and amplitude. The amplitude and area under the curve of [Ca2+ ]i flux was increased in high (1.2 mM) [Ca2+ ]o media. 18α-glycyrrhetinic acid (18αGA), a gap-junction inhibitor or hexokinase, an ATP scavenger, blocked the wound-induced calcium wave, dependent in part on [Ca2+ ]o . Wounding in a high [Ca2+ ]o increased nuclear factor of activated T-cells (NFAT) but not NFkB activation, assessed by dual-luciferase receptor assays compared to unwounded cells. Treatment with 18αGA or the store-operated channel blocker GSK-7975A inhibited wound-induced NFAT activation, whereas treatment with hexokinase did not. Real-time cell migration analysis, measuring wound closure rates over 24 h, revealed that 18αGA essentially blocked wound closure whereas hexokinase and GSK-7975A showed relatively minimal effects. Together these data indicate that while both gap-junction communication and ATP release from damaged cells are important in regulating the wound-induced calcium wave, long-term transcriptional and functional responses are dominantly regulated by gap-junction communication.

Feasibility trial of an early therapy in perinatal stroke (eTIPS).

BACKGROUND: Perinatal stroke (PS) affects up to 1/2300 infants and frequently leads to unilateral cerebral palsy (UCP). Preterm-born infants affected by unilateral haemorrhagic parenchymal infarction (HPI) are also at risk of UCP. To date no standardised early therapy approach exists, yet early intervention could be highly effective, by positively influencing processes of activity-dependent plasticity within the developing nervous system including the corticospinal tract. Our aim was to test feasibility and acceptability of an "early Therapy In Perinatal Stroke" (eTIPS) intervention, aiming ultimately to improve motor outcome. METHODS: Design: Feasibility trial, North-East England, August 2015-September 2017. Participants were infants with PS or HPI, their carers and therapists. The intervention consisted of a parent-delivered lateralised therapy approach starting from term equivalent age and continuing until 6 months corrected age. The outcome measures were feasibility (recruitment and retention rates) and acceptability of the intervention (parental questionnaires including the Warwick-Edinburgh Mental Wellbeing Scale (WEBWMS), qualitative observations and in-depth interviews with parents and therapists). We also reviewed clinical imaging data and undertook assessments of motor function, including the Hand Assessment for Infants (HAI). Assessments were also piloted in typically developing (TD) infants, to provide further information on their ease of use and acceptability. RESULTS: Over a period of 18 months we screened 20 infants referred as PS/HPI: 14 met the inclusion criteria and 13 took part. At 6 months, 11 (85%) of those enrolled had completed the final assessment. Parents valued the intervention and found it acceptable and workable. There were no adverse events related to the intervention. We recruited 14 TD infants, one of whom died prior to undertaking any assessments and one of whom was subsequently found to have a condition affecting neurodevelopmental progress: thus, data for 12 TD infants was analysed to 6 months. The HAI was well tolerated by infants and highly valued by parents. Completion rates for the WEBWMS were high and did not suggest any adverse effect of engagement in eTIPS on parental mental wellbeing. CONCLUSION: The eTIPS intervention was feasible to deliver and acceptable to families. We plan to investigate efficacy in a multicentre randomised controlled trial. TRIAL REGISTRATION: ISRCTN12547427 (registration request submitted 28/05/2015; retrospectively registered, 30/09/2015).

The Tyneside Pegboard Test: development, validation, and observations in unilateral cerebral palsy.

AIM: The aims of this study were twofold: first, to develop and validate a timed test of unimanual and bimanual dexterity suitable for those with disability affecting hand function; second, to explore relationships between unimanual and bimanual completion times. METHOD: We developed the Tyneside Pegboard Test (TPT), an electronically timed test with three peg sizes, incorporating an asymmetrical bimanual task. Nine hundred and seventy-four participants (455 males, 519 females; age range 4-80y) provided normative data. Test-retest reliability and construct validity were assessed (50 adults: 14 males, 36 females; 15-73y) on two occasions 2 weeks apart. Bimanual and unimanual completion times were measured in 87 children (51 males, 36 females) with unilateral cerebral palsy (CP) and 498 individuals in a comparison group (238 males, 260 females; 5-15y). RESULTS: The comparison group showed an asymmetrical U-shaped relationship between completion times and age. Intraclass correlation coefficients ranged from 0.74 to 0.91, indicating moderate test-retest reliability. There was a negative relationship between average TPT bimanual times and Purdue pegboard bimanual scores (Spearman's rho -0.611, degrees of freedom 44, p<0.001). Children with unilateral CP had greater prolongation of bimanual than unimanual completion times compared with the comparison group (mean difference 20.31s, 95% confidence interval 18.13-22.49, p<0.001). INTERPRETATION: The TPT is accessible for those with impaired hand function. Children with unilateral CP demonstrated disproportionate bimanual deficits, even allowing for unimanual dexterity: this has implications for therapy. WHAT THIS PAPER ADDS: We developed an adapted, electronically timed 9-hole pegboard test. Our modifications facilitate use by those with disability affecting hand function. The test incorporates an asymmetrical bimanual task. Children with unilateral cerebral palsy showed disproportionate bimanual dexterity deficits even allowing for unimanual dexterity.