New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Freezing influences diffusion of reducing sugars in carrot cortex

The loss of reducing sugars from raw and previously frozen carrot cortex tissue immersed in warm water was studied as a function of temperature (40–100°C). Leaching was described as a diffusional mechanism by application of Fick's 2nd law. This approach successfully modeled losses from raw carrots at temperatures higher than 60°C. At low temperatures diffusion was much slower, due to a high resistence of the tissues to mass transfer, and Fick's 2nd law could not be applied. Previously frozen carrots showed a Fickian behaviour through the range of temperatures and diffusivities were much higher. Dependence of diffusivity on temperature followed an Arrhenius type equation for the two cases. However, the activation energy of pre-frozen carrots was lower, indicating loss of sensitivity to temperature variations.info:eu-repo/semantics/acceptedVersio