Maintaining post-operative mechanical stability is crucial for successfully healing intertrochanteric fractures treated with the Proximal Femoral Nail Antirotation (PFNA) system. This stability is primarily dependent on the bone mineral density (BMD) and strain on the fracture. Current PFNA failure analyses often overlook the uncertainties related to BMD and body weight (BW).
View Article and Find Full Text PDFBackground: Observational research has shed light on the ability of gut microbes to influence the onset and progression of gastrointestinal diseases. The causal relationships between specific gut microbiomes and various gastrointestinal conditions, however, remain unknown.
Methods: We investigated the relationship between gut microbiota and seven specific gastrointestinal disorders using a robust two-sample Mendelian randomization (MR) approach.
Patient-specific coronary endothelial shear stress (ESS) calculations using Newtonian and non-Newtonian rheological models were performed to assess whether the common assumption of Newtonian blood behavior offers similar results to a more realistic but computationally expensive non-Newtonian model. 16 coronary arteries (from 16 patients) were reconstructed from optical coherence tomographic (OCT) imaging. Pulsatile CFD simulations using Newtonian and the Quemada non-Newtonian model were performed.
View Article and Find Full Text PDFObjectives: This study aimed to investigate the impact of mechanical factors at baseline on the patency of a restorative conduit for coronary bypass grafts in an ovine model at serial follow-up up to 1 year.
Methods: The analyses of 4 mechanical factors [i.e.
One particular complexity of coronary artery is the natural tapering of the vessel with proximal segments having larger caliber and distal tapering as the vessel get smaller. The natural tapering of a coronary artery often leads to proximal incomplete stent apposition (ISA). ISA alters coronary hemodynamics and creates pathological path to develop complications such as in-stent restenosis, and more worryingly, stent thrombosis (ST).
View Article and Find Full Text PDF"Controlled particle release and targeting" is a technique using particle release score map (PRSM) and transient particle release score map (TPRSM) via backtracking to determine optimal drug injection locations for achieving an enhanced target efficiency (TE). This paper investigates the possibility of targeting desired locations through an idealized but complex three-dimensional (3D) vascular tree geometry under realistic hemodynamic conditions by imposing a Poiseuille velocity profile and a Womersley velocity profile derived from cine phase contrast magnetic resonance imaging (MRI) data for steady and pulsatile simulations, respectively. The shear thinning non-Newtonian behavior of blood was accounted for by the Carreau-Yasuda model.
View Article and Find Full Text PDFThe deployment of a coronary stent near complex lesions can sometimes lead to incomplete stent apposition (ISA), an undesirable side effect of coronary stent implantation. Three-dimensional computational fluid dynamics (CFD) calculations are performed on simplified stent models (with either square or circular cross-section struts) inside an idealised coronary artery to analyse the effect of different levels of ISA to the change in haemodynamics inside the artery. The clinical significance of ISA is reported using haemodynamic metrics like wall shear stress (WSS) and wall shear stress gradient (WSSG).
View Article and Find Full Text PDF