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MARTINI is a popular coarse-grained (CG) force-field that is used in molecular dynamics (MD) simulations. It is based on the "Lego" approach where nonbonded interactions between CG beads representing chemical units of different polarity are obtained through water–octanol partition coefficients. This enables the simulation of a wide range of molecules by only using a finite number of parametrized CG beads, similar to the Lego game, where a finite number of brick types is used to create larger structures. Moreover, the MARTINI force-field is based on the Lennard–Jones potential with the shortest possible cutoff including attractions, thus rendering it very efficient for MD simulations. However, MD simulation is in general a computationally expensive method. Here, we demonstrate that using the MARTINI "Lego" approach is suitable for many-body dissipative particle (MDPD) dynamics, a method that can simulate multi-component and multi-phase soft matter systems in a much faster time than MD. In this study, a DPPC lipid bilayer is chosen to provide evidence for the validity of this approach and various properties are compared to highlight the potential of the method, which can be further extended by introducing new CG bead types. [ABSTRACT FROM AUTHOR]

We report a patient with coronary dilatation 10 weeks after paclitaxel-eluting stent implantation in the right coronary artery (RCA). Coronary angiography demonstrated a double-locular lumen dilatation in the body of the stented segment of the RCA, and intravascular ultrasound interrogation revealed the corresponding region with evidence of tissue regression behind the stent struts, incomplete stent apposition, and lumen enlargement. After three-dimensionally (3D) reconstructing the RCA, we applied computational fluid dynamics to the 3D RCA model, representing the lumen of the artery at the moment of stent implantation, and investigated the correlation of both neointimal thickness and tissue regression depth with shear stress in the stent. Neointimal thickness was found to be inversely related to shear stress, but there was no significant association of tissue regression depth with shear stress. Post-procedural stent malapposition, thrombus dissolution, and less possibly, a localized hypersensitivity reaction are potential mechanisms for the lumen enlargement in this case. [ABSTRACT FROM AUTHOR]