The Wheelchair Circuit: Construct Validity and Responsiveness of a Test to Assess Manual Wheelchair Mobility in Persons With Spinal Cord Injury

Kilkens OJ, Dallmeijer AJ, de Witte LP, van der Woude LH, Post MW. The Wheelchair Circuit: construct validity and responsiveness of a test to assess manual wheelchair mobility in persons with spinal cord injury. Arch Phys Med Rehabil 2004;85:424-31. Objective To assess the validity and responsiveness of the Wheelchair Circuit, a test to assess manual wheelchair mobility in persons with spinal cord injury (SCI). Design Longitudinal. Subjects performed the Wheelchair Circuit at the start (T1) and at the end (T3) of inpatient functional rehabilitation. Construct validity and responsiveness were assessed. Setting Eight rehabilitation centers in the Netherlands. Participants Seventy-four subjects with SCI admitted for inpatient rehabilitation. Interventions Not applicable. Main outcome measures The Wheelchair Circuit consists of 8 wheelchair skills and results in 3 test scores: ability, performance time, and physical strain. The construct validity of the Wheelchair Circuit was assessed by testing whether the test scores were significantly related to the subjects' functional status, physical capacity, lesion level, motor completeness of the lesion, and age. To prove the test's responsiveness, it was assessed whether the test scores had significantly improved between T1 and T3. Results For construct validity, 4 of the 5 hypotheses were confirmed. For test responsiveness, all 3 test scores had significantly improved during rehabilitation, and the standardized response mean values ranged from 0.6 to 0.9. Conclusions The Wheelchair Circuit is a valid and responsive instrument with which to measure manual wheelchair mobility in subjects with SCI. © 2004 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Candidate CSPG4 mutations and induced pluripotent stem cell modeling implicate oligodendrocyte progenitor cell dysfunction in familial schizophrenia

Schizophrenia is highly heritable, yet its underlying pathophysiology remains largely unknown. Among the most well-replicated findings in neurobiological studies of schizophrenia are deficits in myelination and white matter integrity; however, direct etiological genetic and cellular evidence has thus far been lacking. Here, we implement a family-based approach for genetic discovery in schizophrenia combined with functional analysis using induced pluripotent stem cells (iPSCs). We observed familial segregation of two rare missense mutations in Chondroitin Sulfate Proteoglycan 4 (CSPG4) (c.391G > A [p.A131T], MAF 7.79 × 10−5 and c.2702T > G [p.V901G], MAF 2.51 × 10−3). The CSPG4A131T mutation was absent from the Swedish Schizophrenia Exome Sequencing Study (2536 cases, 2543 controls), while the CSPG4V901G mutation was nominally enriched in cases (11 cases vs. 3 controls, P = 0.026, OR 3.77, 95% CI 1.05–13.52). CSPG4/NG2 is a hallmark protein of oligodendrocyte progenitor cells (OPCs). iPSC-derived OPCs from CSPG4A131T mutation carriers exhibited abnormal post-translational processing (P = 0.029), subcellular localization of mutant NG2 (P = 0.007), as well as aberrant cellular morphology (P = 3.0 × 10−8), viability (P = 8.9 × 10−7), and myelination potential (P = 0.038). Moreover, transfection of healthy non-carrier sibling OPCs confirmed a pathogenic effect on cell survival of both the CSPG4A131T (P = 0.006) and CSPG4V901G (P = 3.4 × 10−4) mutations. Finally, in vivo diffusion tensor imaging of CSPG4A131T mutation carriers demonstrated a reduction of brain white matter integrity compared to unaffected sibling and matched general population controls (P = 2.2 × 10−5). Together, our findings provide a convergence of genetic and functional evidence to implicate OPC dysfunction as a candidate pathophysiological mechanism of familial schizophrenia

Electrically aligned photo-polymer films for liquid crystal alignment

Contains fulltext : 92651.pdf (publisher's version ) (Closed access

Alignment of nematic liquid crystals on poled photo-polymer films

Contains fulltext : 92637.pdf (publisher's version ) (Closed access

Fast and credible likelihood-free cosmology with truncated marginal neural ratio estimation

Computational astrophysic