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NEUROD1, a basic helix-loop-helix (bHLH) transcription factor, plays an essential role in neurogenesis within both the central and peripheral nervous systems. Recent studies demonstrate its capability to directly reprogram various cell types into neurons. However, these cell-reprogramming experiments indicate that NEUROD1 possesses the ability to instigate cell-fate changes but only under specific conditions that remain incompletely characterized. To gain further insights into the ability of NEUROD1 to change cell-fate and promote neurogenesis in vivo, we used three distinct gain-of-function of Neurodl mouse models. Each model was designed to explore different temporal and spatial over-expression of NEUROD1. Overexpression of NEUROD1 in non-neuronal progenitors resulted in the induction of neurogenesis and neuron generation, while in neuronal progenitors it yielded no discernible changes. Our study provides new evidence that NEUROD1 is an efficient reprogramming factor of non-neuronal progenitors into neurons and confirms its potential for facilitation of reprogramming therapeutic strategy. [ABSTRACT FROM AUTHOR]

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Knowledge of the T2 age dependence is of importance for MRS clinical studies involving subject groups with a wide age range. A number of studies have focused on the age dependence of T2 values in the human brain, with rather conflicting results. The aim of this study was to analyze the age dependence of T2 values of N-acetyl aspartate (NAA), creatine (Cr) and choline (Cho) in the human brain using data acquired at 3T and 4T and to assess the influence of the macromolecule (MM) baseline handling on the obtained results. Two distinct groups of young and elderly controls have been measured at 3T ( TE = 30-540 ms, 9 young and 11 elderly subjects) and 4T ( TE = 10-180 ms, 18 young and 14 elderly subjects) using single-voxel spectroscopy. In addition, MM spectra were measured from two subjects using the inversion-recovery technique at 4T. All spectra were processed with LCModel using basis sets with different MM signals (measured or simulated) and also with MM signals included for a different TE range. Individual estimated T2 values were statistically analyzed using the R programming language for the age dependence of T2 values as well as the influence of the MM baseline handling. A significant decrease of T2 values of NAA and Cr in elderly subjects compared with young subjects was confirmed. The same trend was observed for Cho. Significantly higher T2 values calculated using the measured MM baseline for all studied metabolites at 4T were observed for both young and elderly subjects. To conclude, while the handling of MM and lipid signals may have a significant effect on estimated T2 values, we confirmed the age dependence of T2 values of NAA and Cr and the same trend for Cho in the human brain. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Intorduction: Age related hearing loss (presbycusis) presents itself by elevated auditory thresholds and decreased speech intelligibility especially in a noisy environment. Occurrence of tinnitus (phantom noise) commonly coincides with the onset of presbycusis. Although both are believed to originate from the auditory periphery, they have several functional and morphometric effects also in central parts of auditory and limbic system. Aim: The aim of our project is to identify possible changes within the white matter of auditory pathway above inferior colliculus (IC) and also within the connections towards the limbic system (amygdala). Material and methods: Six groups of volunteers were used in this study: elderly with expressed presbycusis, elderly with mild presbycusis, young controls, elderly with expressed presbycusis and with tinnitus, elderly with mild presbycusis and with tinnitus and subjects with normal hearing and with tinnitus. Tractographic data were acquired using a 3 T Siemens Tim Trio system (Siemens), with a 12-channel head coil. Streamline tracking was performed on common FOD template using probabilistic algorithm iFOD2. Spherical masks on both inferior colliculi were defined manually. Mask of the Heschl gyrus was obtained by applying morphing of Destrieux atlas mask of one representative subject to FOD template. These masks were used as ROIs for targeted exploratory tracking and definition of fixel mask). Fixel based analysis was used for detection of changes (using connectivitybased fixel enhancement, family-wise error corrected) in the following three metrics: fibre density, fibre cross-section, fibre density and cross-section. Results: We were able to identify auditory pathway above the level of IC, and connections from IC towards the amygdala and from AC to amygdala. The only observed changes of the white matter within the auditory and auditory -- limbic pathways were due to ageing. No statistically significant changes due to hearing loss were found. Tinnitus caused a borderline change in the part of the pathway from the inferior colliculus toward amygdala. Conclusions: This is probably the first study using fixel based analysis in the auditory system. Although we were bale to identify age related changes within the studied tracts, in all used metrics, no hearing loss related changes were present. The presence of borderline tinnitus changes in the adjacent pathway from the inferior colliculus to amygdala support the idea of involvement of the limbic system in the tinnitus network. [ABSTRACT FROM AUTHOR]