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Biology subjects

Berni, J.

Publications and source records attributed to Berni, J..

3 recordsLinked to original sources

The female larval fly CNS connectome: first draft

We release an enhanced FIB-SEM volume and associated neuron, mitochondria, synapse and glia automated segmentations for the complete, gap- and artifact-free central nervous system of the first instar female larval Drosophila melanogaster. Segmentation data is largely unproofread besides select neurons in the premotor and proprioceptive system and select subvolumes where synapses have been manually annotated, serving as training and evaluation data. The dataset represents the first complete central nervous system of the larval fly, and now awaits substantial improvement of machine vision approaches that effectively leverage domain knowledge for the automated yet data-guided proofreading, or substantial and costly human proofreading. All the data and methods are publicly available for further improvement and analysis.

neuroscience↗

Adaptation of Drosophila larva foraging in response to changes in food distribution

When foraging, animals combine internal cues and sensory input from their environment to guide sequences of behavioral actions. Drosophila larva executes crawls, turns, and pauses to explore the substrate and find food sources. This exploration has to be flexible in the face of changes in the quality of food so that larvae feed in patches with favorable food and look for another source when the current location does not fulfill their nutritional needs. But which behavioral elements adapt, and what triggers those changes remain elusive. Using experiments and modeling, we investigate the foraging behavior of larvae in homogeneous environments with different food types and in environments where the food sources are patchy. Our work indicates that the speed of larval crawling and frequency of pauses is modulated by the food quality. Interestingly, we found that the genetic dimorphism in the foraging gene influences the exploratory behavior only when larvae crawl on yeast patches. While in a homogeneous substrate larvae maintain a turning bias in a specific orientation, in a patchy substrate larvae orient themselves towards the food when the patch border is reached. Therefore, by adapting different elements in their foraging behavior, larvae either increase the time inside nutritious food patches or continue exploring the substrate in less nutritious environments.

animal behavior and cognition↗

Behavioural Evaluation of the Anticonvulsant Properties of the Traditional Medicine Anonna Senegalensis on Parabss Drosophila melanogaster Mutants.

Epilepsy is the most common serious neurological disorder affecting 50 million people worldwide, 40 millions of which live in developing countries. Despite the introduction of a dozen of new Anti-Epileptic Drugs (AEDs), one third of the patients continue to have seizure regardless of receiving a AEDs treatment. This emphasize on the need to discover new drugs with different mechanisms of action. Traditional medicine (TM), pays a significant role in the treatment of epilepsy in many countries and offers an affordable and accessible alternative to AEDs. However, the lack of both empirical testing in animal models and clinical data places constrains to their clinical recommendation.\n\nIn this study, we use Drosophila melanogaster as a model for epilepsy and tested the anti-seizure effect of leaf and stem bark aqueous extract form Annona senegalensis, a plant used as anti-convulsant by rural populations in Africa.\n\nOur results show, that at the concentrations tested, the leaf extract of A. senegalensis was more effective than the AEDs phenytoin and phenobarbital to control seizures. These promising results demonstrate that Drosophila is an excellent model for new drug discovery and that it could be used to do large scale screening of TMs for the treatment of epilepsy.

pharmacology and toxicology↗