Engineering in vitro human neural tissue analogs by 3D bioprinting and electrostimulation.

There is a fundamental need for clinically relevant, reproducible, and standardized in vitro human neural tissue models, not least of all to study heterogenic and complex human-specific neurological (such as neuropsychiatric) disorders. Construction of three-dimensional (3D) bioprinted neural tissues from native human-derived stem cells (e.g., neural stem cells) and human pluripotent stem cells (e.g., induced pluripotent) in particular is appreciably impacting research and conceivably clinical translation. Given the ability to artificially and favorably regulate a cell's survival and behavior by manipulating its biophysical environment, careful consideration of the printing technique, supporting biomaterial and specific exogenously delivered stimuli, is both required and advantageous. By doing so, there exists an opportunity, more than ever before, to engineer advanced and precise tissue analogs that closely recapitulate the morphological and functional elements of natural tissues (healthy or diseased). Importantly, the application of electrical stimulation as a method of enhancing printed tissue development in vitro, including neuritogenesis, synaptogenesis, and cellular maturation, has the added advantage of modeling both traditional and new stimulation platforms, toward improved understanding of efficacy and innovative electroceutical development and application.

Further development of the response scales of the Acquired Brain Injury Challenge Assessment (ABI-CA).

PRIMARY OBJECTIVE: To revise the scaling of the response sets of the Acquired Brain Injury Challenge Assessment (ABI-CA) through expert input and determination of empirically based cut-points. RESEARCH DESIGN: A measurement development study with a content validity focus. METHODS: Response option wording was revised through consultation with six physiotherapists with paediatric ABI expertise. Twenty-nine typically-developing children performed the ABI-CA and empirically-based cut-points for item-specific response options were derived from their time/distance/repetition results (SD values) as benchmark values. Movement quality considerations (compensatory movements) were identified from expert consultation/ABI-CA video observation and built into revised response options. The revised ABI-CA was pilot-tested with four children with ABI, aged 7-15 years, for a feasibility check. RESULTS: Nineteen of the 23 items' response scales were revised based on experts' feedback and empirically-based cut-points replaced the previous arbitrarily-determined cut-points. Compensatory movement considerations were re-defined in nine items. The mean score of the refined ABI-CA was 70.0% (SD = 18.5) with four children with ABI. CONCLUSION: The new response options in the ABI-CA appeared suitable for testing high-functioning children with ABI and the mid-range mean score in this pilot sample indicates its potential to measure change. Recommendations are outlined for final ABI-CA amendments before large-scale validation.