ABSTRACT
OBJECTIVE: To investigate the effect of gene polymorphisms in hypoxia-inducible factor 1α (HIF-1α) in left ventricular hypertrophy of hypertensive patients. PATIENTS AND METHODS: A total of 583 hypertensive patients were divided into two groups, with left ventricular hypertrophy (LVH (+), 198 cases) and without left ventricular hypertrophy (LVH (-), 385 cases). Polymerase Chain Reaction restriction fragment length polymorphism was used to detect the single nucleotide gene polymorphisms rs11549465, rs11549467 and rs1957757 in HIF-1α. RESULTS: The distribution differences of gene frequencies for rs11549465, rs11549467 and rs1957757 in HIF1A single nucleotide gene polymorphisms for LVH (+) and LVH (-) were statistically significant (p<0.05). The T allele of rs11549465 loci and the G allele of rs11549467 loci increased the risk of LVH, related to the increased plasma expression of HIF-1α (p<0.05). CONCLUSIONS: Gene polymorphism of HIF-1α were related to primary hypertensive left ventricular hypertrophy, and the expression of rs11549467 correlated with the increasing concentration of plasma HIF-1α.
Subject(s)
Asian People , Hypertension/metabolism , Hypertrophy, Left Ventricular/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Aged , China , Echocardiography , Female , Genetic Predisposition to Disease , Humans , Hypertension/complications , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Male , Middle Aged , Polymorphism, Single NucleotideABSTRACT
OBJECTIVE: To quantify stress distribution of the foot during mid-stance to push-off in barefoot gait using 3-D finite element analysis. DESIGN: To simulate the foot structure and facilitate later consideration of footwear. Finite element model was generated and loading condition simulating barefoot gait during mid-stance to push-off was used to quantify the stress distributions. BACKGROUND: A computational model can provide overall stress distributions of the foot subject to various loading conditions. METHODS: A preliminary 3-D finite element foot model was generated based on the computed tomography data of a male subject and the bone and soft tissue structures were modeled. Analysis was performed for loading condition simulating barefoot gait during mid-stance to push-off. RESULTS: The peak plantar pressure ranged from 374 to 1003 kPa and the peak von Mises stress in the bone ranged from 2.12 to 6.91 MPa at different instants. The plantar pressure patterns were similar to measurement result from previous literature. CONCLUSIONS: The present study provides a preliminary computational model that is capable of estimating the overall plantar pressure and bone stress distributions. It can also provide quantitative analysis for normal and pathological foot motion. RELEVANCE: This model can identify areas of increased pressure and correlate the pressure with foot pathology. Potential applications can be found in the study of foot deformities, footwear, surgical interventions. It may assist pre-treatment planning, design of pedorthotic appliances, and predict the treatment effect of foot orthosis.
