The Subventricular Zone, a Hideout for Adult and Pediatric High-Grade Glioma Stem Cells

Both in adult and children, high-grade gliomas (WHO grades III and IV) account for a high proportion of death due to cancer. This poor prognosis is a direct consequence of tumor recurrences occurring within few months despite a multimodal therapy consisting of a surgical resection followed by chemotherapy and radiotherapy. There is increasing evidence that glioma stem cells (GSCs) contribute to tumor recurrences. In fact, GSCs can migrate out of the tumor mass and reach the subventricular zone (SVZ), a neurogenic niche persisting after birth. Once nested in the SVZ, GSCs can escape a surgical intervention and resist to treatments. The present review will define GSCs and describe their similarities with neural stem cells, residents of the SVZ. The architectural organization of the SVZ will be described both for humans and rodents. The migratory routes taken by GSCs to reach the SVZ and the signaling pathways involved in their migration will also be described hereafter. In addition, we will debate the advantages of the microenvironment provided by the SVZ for GSCs and how this could contribute to tumor recurrences. Finally, we will discuss the clinical relevance of the SVZ in adult GBM and pediatric HGG and the therapeutic advantages of targeting that neurogenic region in both clinical situations

Eye movement responses to caloric vestibular irrigations reveal the contribution of voluntary processes to autonomic reflexes

editorial reviewedCan autonomic reflexes inform us about higher-order cognitive processes ? To address this issue, we studied habituation (a form of non-associative learning) of the slow, uncontrolled eye movement response (nystagmus) following repetitive caloric (warm water) vestibular irrigation. After a 30s irrigation trial (total trials=6), participants (n=26) either kept their gaze fixated, or let their gaze free, testing voluntary adaptations of the nystagmus response measured with electrooculography (EOG). Participants also reported the intensity of the vertigo that they experienced after each irrigation. We found that the amplitude of the nystagmus response decreased over repetitive irrigations, revealing a clear habituation (repeated measures ANOVA with participants as random factor, F(5)=-18.8, p<0.001). We further showed that the amplitude of nystagmus is reduced after the gaze fixation condition compared to the freely moving gaze (interaction between irrigation and fixation, F(5,1)=5.1, p=0.025). Finally, by relying on a model comparison approach, we demonstrate that the oculomotor response holds partial information on the decrease of the vertigo experienced over successive irrigations, suggesting a bi-directional interaction between central and autonomic processes (Likelihood-ratio chi-squared test between mixed-models predicting vertigo response and including or excluding the duration of nystagmus, 2(12)=11.96, p=0.013). These findings suggest that reflexes carry partial information about voluntary processes. From the interoceptive active inference framework, these results might be relevant for evidencing signs of sentience when this cannot be communicated overtly

Data analysis

End-September 2019: Inclusion of the various scripts allowing the creation of specific dataframe and the statistical analysis of the data. Statistical test: Post Irrigation Questionnaire: Trend Test Nystagmus: Non parametric test (Wilcoxon) Correction Bonferron

Model (Cluster permutation test) Analysis

End of October: Addition of the script allowing the creation of the dataframe for statistical analysis by Cluster Permutation Test

Create dataframe and Statistical test

End-September 2019: Inclusion of the various scripts allowing the creation of specific dataframe and the statistical analysis of the data. Statistical test: Post Irrigation Questionnaire: Trend Test Nystagmus: Non parametric test (Wilcoxon) Correction Bonferron

Volitional activity is partially carried in autonomic reflexive responses

Physiological and neurobiological determinations of voluntary and reflex responses as well as the effect of habituation after vestibular stimulation by caloric irrigation in healthy subjects

Development of highly validated SNP markers for genetic analyses of chestnut species

To better study and manage chestnut trees and species, we identified nuclear single nucleotide polymorphism (SNP) markers using restriction-associated DNA sequencing. Out of 343 loci tested, 68 SNP markers were selected that withhold stringent quality criteria such as quasi-systematic amplification across species and Mendelian segregation in both purebred and hybrid individuals. They provide sufficient power for species, hybrids and backcross characterization as well as for clonal identification, as shown by a comparison with single sequenced repeat (SSR) loci.Plateforme d'Innovation " Forêt-Bois-Fibre-Biomasse du Futur