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Vignon-Clementel, I.

Publications and source records attributed to Vignon-Clementel, I..

2 recordsLinked to original sources

Additive Manufacturing of real-scale carotid artery models: The content-container interaction in sickle cell disease-related cerebral vasculopathy

Sickle cell disease-related cerebral vasculopathy depends on patient-specific vascular geometry and hemodynamics that are not captured by conventional experimental systems or animal models. To address this limitation, we developed an additively manufactured artery scaffold representing the container and integrated it into a controlled fluidic circuit reproducing physiological flow profiles, pressures, and viscosities, the content. Validation with clinical imaging confirmed the anatomical accuracy and flow fidelity of the additively manufactured models. Mechanosensitive cells, including endothelial cells and platelets, were incorporated into the model for biological analysis. This study serves as a proof of concept demonstrating how the Container-Content model can enhance the mechanistic understanding of vascular biology under physiologically relevant conditions. The ethically responsible platform bridges computational simulations and in vitro experimentation, offering a versatile foundation for investigating cerebrovascular complications in sickle cell disease and advancing the field of personalized medicine.

bioengineering↗

Intravital multi-modal flux analysis reveals the transport mechanism of bile acids through hepatic microconduits

Small-molecule flux in tissue-microdomains is essential for organ function, but knowledge of this process is scant due to the lack of suitable methods. We developed two independent techniques that allow the quantification of advection (flow) and diffusion in individual bile canaliculi and in interlobular bile ducts of intact livers in living mice, namely Fluorescence Loss After Photoactivation (FLAP) and Intravital Arbitrary Region Image Correlation Spectroscopy (IVARICS). The results challenge the prevailing ‘mechano-osmotic’ theory of canalicular bile flow. After active transport across hepatocyte membranes bile acids are transported in the canaliculi primarily by diffusion. Only in the interlobular ducts, diffusion is augmented by regulatable advection. Photoactivation of fluorescein bis-(5-carboxymethoxy-2-nitrobenzyl)-ether (CMNB-caged fluorescein) in entire lobules demonstrated the establishment of diffusive gradients in the bile canalicular network and the sink function of interlobular ducts. In contrast to the bile canalicular network, vectorial transport was detected and quantified in the mesh of interlobular bile ducts. In conclusion, the liver consists of a diffusion dominated canalicular domain, where hepatocytes secrete small molecules and generate a concentration gradient and a flow-augmented ductular domain, where regulated water influx creates unidirectional advection that augments the diffusive flux.One Sentence Summary/Keywords Bile flux proceeds by diffusion in canaliculi, augmented by advection in ducts.Competing Interest StatementThe authors have declared no competing interest.View Full Text

physiology↗