Signalling-modulated gene regulatory networks in early mammalian development.

Early mammalian embryo is a paradigm of dynamic, self-organised process. It involves gene expression, cell division and intercellular signalling. How these processes interact to ensure reproducible development is being often investigated by modelling, which allows to dissect the mechanisms controlling cell fate decisions.

Modeling the photoperiodic entrainment of the plant circadian clock.

The circadian clock is an endogenous 24 hour rhythm that helps organisms anticipate and adapt to daily and seasonal variations in environment, such as the day/night cycle or changing temperatures. The plant clock is a complex network of transcription factors that regulate each other, forming interlocked feedback loops. Most of its components are light-regulated in some way, making the system highly sensitive to changes in light conditions.

A Compact Model for the Complex Plant Circadian Clock.

The circadian clock is an endogenous timekeeper that allows organisms to anticipate and adapt to the daily variations of their environment. The plant clock is an intricate network of interlocked feedback loops, in which transcription factors regulate each other to generate oscillations with expression peaks at specific times of the day. Over the last decade, mathematical modeling approaches have been used to understand the inner workings of the clock in the model plant Arabidopsis thaliana.

The progression towards Alzheimer's disease described as a bistable switch arising from the positive loop between amyloids and Ca(2+).

Alzheimer's disease is a progressive neurodegenerative disorder affecting millions of people. It is characterized by the slow deposition of cerebral amyloid-β peptides in the brain and by dysregulations in neuronal Ca(2+) homeostasis. Numerous experimental studies have revealed the existence of a feed-forward loop wherein amyloids-β disturb neuronal Ca(2+) levels, which in turn affect the production of amyloids.

[Lead poisoning caused by prolonged use of kohl, an underestimated cause in French-speaking countries].

Use of kohl (called surma in India and Pakistan) as an eye cosmetic is very common, especially among women, children, and babies, not only in North Africa (Morocco, Algeria, Egypt), but also in the Near East and the Middle East, as well in India and Pakistan. This practice has now become widespread in European countries and North America. The cultural custom is very old and has been in use in Egypt since the Ancient Empire.