Predictive value of definitely abnormal general movements in the general population

Aim Definitely abnormal general movements in populations of high‐risk infants predict serious neurodevelopmental impairment. This study aimed to assess predictive values of definitely abnormal general movements at 3 months for serious neurodevelopmental impairment in a representative sample of the general population. Method A prospective cohort study of 455 3‐month‐old infants was performed (241 females, 214 males; mean birthweight 3452g, SD 604g; mean gestational age 39.4wks, SD 1.96; n=32 born preterm). At enrolment, general movement quality was assessed by means of video recording. At 4 years, all participants were reassessed by well‐baby health clinicians; if serious neurodevelopmental impairment was identified, clinical records were reviewed. Predictive values of definitely abnormal general movement quality for major neurodevelopmental impairment were calculated. Results Five children were diagnosed as having a major neurodevelopmental disorder with serious implications for daily life, including three children with cerebral palsy (CP). Three out of the five had shown definitely abnormal general movements; they had lesions involving the periventricular white matter. Two children did not show definitely abnormal general movements; one had unilateral spastic CP due to a cortical lesion and the other had ataxia due to cerebellar atrophy. The positive predictive value of definitely abnormal general movements for major neurodevelopmental impairment was 18/100, and for CP it was 12/100. Negative predictive values approached 100%. Interpretation The good predictive value of general movement assessment in high‐risk populations cannot be generalized to the general population.     

Wide-angle X-ray Diffraction of Human Stratum Corneum: Effects of Hydration and Terpene Enhancer Treatment

Abstract— Wide-angle X-ray-diffraction experiments were used to investigate the molecular organization of barrier components of human stratum corneum. Diffraction lines related to the side-by-side lipid packing arrangements in the intercellular bilayers were identified as were patterns arising from secondary protein structures in intracellular keratin. Reflections were also identified which may be produced by proteins in the corneocyte envelopes. The effects of hydration on stratum corneum structure were monitored using 0, 20–40, 40–60, 60–80 and approximately 300% hydrated samples. The packing arrangements in the intercellular lipid bilayers remained the same over the entire hydration range, as did keratin structures. A new diffraction ring, attributable to liquid water, was produced by 300% hydrated samples with a repeat spacing of 0.35 to 0.30-0.29 nm. The effects of three terpene enhancers, (+)-limonene, nerolidol and 1,8-cineole, on stratum corneum structure were monitored. Treatment with each of the terpenes produced additional reflections which were attributed to the presence of the respective liquid enhancers within the stratum corneum. (+)-Limonene produced an additional reflection at 0.503-0.489 nm, nerolidol, an additional reflection at 0.486-0.471 nm and 1,8-cineole, an intense reflection at 0.583–0.578 nm. Reflections characteristic of gel-phase lipids and crystalline lipids also remained after all terpene treatments. These results provide no clear evidence of lipid bilayer disruption by the terpenes and suggest that areas of liquid terpene exist within the stratum corneum. The mechanisms underlying propylene glycol synergy with terpene enhancers were investigated. Treatment of stratum corneum with each terpene mixed with propylene glycol gave rise to two additional reflections. One reflection, always positioned at 0.452–0.448 nm, had been observed in control studies following propylene glycol treatment and may have been associated with bilayer structures disrupted by propylene glycol or altered keratin structures. The second reflection was developed by the respective terpene enhancer. For example, treatment with a 1,8-cineole/propylene glycol mixture produced reflections at 0.457—0.451 nm (propylene glycol-disrupted lipids or altered keratin) and 0.591—0.578 nm (liquid 1,8-cineole). Since the reflection at 0.452—0.448 nm was unaffected by co-application of propylene glycol with terpene enhancers, this study offers no evidence to support the theory that propylene glycol synergy with the terpenes occurs through enhanced lipid disruption.