Faculty Bibliography

Spinocerebellar ataxia type 14 (SCA14) is an autosomal dominant neurodegenerative disorder characterized by adult-onset cerebellar ataxia, and occasionally pyramidal signs, cognitive changes, sensory changes, myoclonus, and tremor. SCA14 results from heterozygous gain-of-function pathogenic variants in PRKCG, which encodes protein kinase Cγ. The aim was to elucidate the molecular mechanism of disease in a 60-year-old man with SCA14 due to a novel heterozygous variant in PRKCG c.154T > C p.(C52R). Next-generation sequencing was completed in the proband, targeted variant analysis was conducted in his family, and biochemical functional assays were performed. The C52R variant segregated with disease. Like other C1A domain variants, it had increased basal activity yet was unresponsive to agonist stimulation and was relatively resistant to down-regulation. This expands the genetic landscape of SCA14 and supports the condition as a gain-of-function disease, with variants in the C1A domain having leaky activity yet unresponsiveness to agonist stimulation.

This study examined the effects of KT tape (KT) applied in an inhibitory manner on muscle activity, measured maximal grip strength, and perceived maximal grip strength in regular KT-users and non-users. This study was a single-blinded crossover study with sixty participants including 27 kT-users and 33 non-users. Participants underwent maximal grip strength tests with and without inhibitory KT applied across the wrist extensors. Muscle activity and maximal grip strength were measured, while perceived maximal grip strength was rated using a visual analogue scale. No significant interaction effect was found between taping conditions and participant KT-experience for muscle activity (F = 0.825, p = 0.367), measured grip strength (F = 1.018, p = 0.317) or perceived grip strength (F = 0.122, p = 0.728). No significant differences were observed in the EMG activity between taping conditions for either KT-users (p = 0.367) or non-users (p = 0.215). A similar trend was found in the measured grip strength (KT-users: p = 0.317; non-users: p = 0.294) and perceived grip strength (KT-users: p = 0.728; non-users: p = 0.063). KT applied in an inhibitory manner does not impede EMG activity, measured maximal grip strength, or perceived maximal grip strength in adults, regardless of their preconceived notions of KT.