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Biology subjects

Bruno, D. C. F.

Publications and source records attributed to Bruno, D. C. F..

2 recordsLinked to original sources

EPILEPTOGENESIS INHIBITS THE CIRCADIAN CLOCK AND RESHAPES THE DIURNAL TRANSCRIPTOMIC RHYTHMICITY IN THE MOUSE HIPPOCAMPUS

Epileptogenesis is the process that leads the brain into epileptic activity. Clinical evidence shows that [~]90% of people with epilepsy present rhythmicity in the timing of their seizures presentation. However, whether the circadian clock is a key player during epileptogenesis remains unknown. Here, we triggered epileptogenesis in mice by the intra-amygdala injection of kainic acid and profiled by RNA sequencing their hippocampal diurnal mRNA rhythmicity. We show that epileptogenesis largely reshapes the hippocampal transcriptomic rhythmicity and that the molecular clock machinery is inhibited due to the disruption of the core clock gene Bmal1. We identified relevant dysregulated pathways and their dynamics in epileptogenesis, predicting a key role for microglial-driven neuroinflammation. We predicted the genes that Bmal1 is directly controlling over time. Finally, we sought for translational relevance evidence by performing RNA sequencing in hippocampal samples resected from patients with mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS) and cross-analyzing datasets.

neuroscience↗

Experimental evolution and genome data analysis of Candida albicans reveals cryptic bacteria in single yeast colonies

At least 25% of patients with positive Candida albicans bloodstream infection also have one or more bacterial species associated with the infection. These polymicrobial infections are usually caused by coagulase-negative staphylococci, most commonly Staphylococcus epidermidis and are associated with significantly worse clinical outcomes as compared to monomicrobial infections. Here we show bacteria are present in C. albicans cultures started from isolated single colony platting. These co-evolving bacteria can only be detected by the use of specific selective medium and/or long periods of incubation from 8 days up to 48 weeks (approximately 4,000 generations), used in experimental evolution methods. The detection of these co-evolving bacteria is highly dependent on the type of enzyme used for 16S rRNA gene amplification and is often missed in clinical laboratory analysis because of short incubation periods, media and temperatures, used in mycology clinical routine, that are unfavorable for bacterial growth. In this study, we identified bacteria in cultures of different C. albicans isolates from long term, continuous growth by molecular analysis and microscopy. Also, we confirmed the presence of these co-evolving bacteria by identification of S. epidermidis genome segments in sequencing reads of the C. albicans reference strain SC5314 genome sequencing project raw data deposited in GenBank. This result rules out the possibility of laboratory specific contamination. Also, we show that the presence of associated bacteria correlates with antifungal resistance alterations observed in growth under hypoxia. Our findings show the intense interaction between C. albicans yeasts and bacteria and have direct implications in yeast clinical procedures, especially concerning patient treatment.

microbiology↗