Overlooked Implications of Disturbed Sleep in Traumatic Brain Injury

Abstract

nucleic acid species at levels that are undetectable by conventional spectroscopic methods. Thus, it is essential to perform mNGS on no-template controls regardless of whether nucleic acid can be detected postextraction.Power et al state that they subtracted "any nonhuman hits that were common across unconnected libraries in a manner similar to [our] background subtraction approach." We did not subtract common sequences, but rather their rank was lowered in our z score-based algorithm to indicate that the organism's level of abundance was typical for controls.The variance in the relative abundance of the 4 bacterial classes that were identified in our water controls was generally wider than in the brain mNGS data sets from Power et al. Even within batched mNGS data sets, wide sample-tosample variation is common because of sample-to-sample variability in contamination levels that arise from nonreagent sources, sample-to-sample variation in input amounts of nucleic acid (see RNA doping experiments), and differences in sample handling during mNGS library preparation.We commend Power et al for detecting bacterial RNA by in situ hybridization and assessing for bacterial protein immunoreactivity. However, the former experiments are subject to some of the same potential pitfalls as mNGS, and the latter were not specific for the variety of bacterial taxa on which the claim of a multiple sclerosis brain dysbiosis was made. Given the overlap between the microbiota of laboratory-grade reagents generated by our mNGS protocol with the microbiota identified by Power et al in autopsy brain tissue, more experiments are required to provide definitive evidence that the organisms reported by Power and colleagues truly represent resident brain microbiota.

Sex‐specific incident dementia in patients with central nervous system trauma

“…Age, sex, disorders of the circulatory system, vascular risk factors, and income quantile (according to postal code) are important in predicting dementia [26–28]. Associative values between sleep disorder [29] and dementia were quantified to determine their effect on dementia onset.…”