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Background Differences in foot structure are thought to be associated with differences in foot function during movement. Many foot pathologies are of a biomechanical nature and often associated with foot type. Fundamental to the understanding of foot pathomechanics is the question: do different foot types have distinctly different structure and function? Aim To determine if objective measures of foot structure and function differ between planus, rectus and cavus foot types in asymptomatic individuals. Methods Sixty-one asymptomatic healthy adults between 18 and 77 years old, that had the same foot type bilaterally (44 planus feet, 54 rectus feet, and 24 cavus feet), were recruited. Structural and functional measurements were taken using custom equipment, an emed-x plantar pressure measuring device, a GaitMatII gait pattern measurement system, and a goniometer. Generalized Estimation Equation modeling was employed to determine if each dependent variable of foot structure and function was significantly different across foot type while accounting for potential dependencies between sides. Post hoc testing was performed to assess pairwise comparisons. Results Several measures of foot structure (malleolar valgus index and arch height index) were significantly different between foot types. Gait pattern parameters were invariant across foot types. Peak pressure, maximum force, pressure-time-integral, force-time-integral and contact area were significantly different in several medial forefoot and arch locations between foot types. Planus feet exhibited significantly different center of pressure excursion indices compared to rectus and cavus feet. Conclusions Planus, rectus and cavus feet exhibited significantly different measures of foot structure and function.

The basic premise central to the diagnosis and treatment of most mechanogenic foot and ankle pathologies is that a given foot will display a characteristic function depending on the biomechanical alignment of the hindfoot and forefoot. However, the effects of foot type on an individual's ability to perform comfortable cadence locomotion have not been scientifically proven. Therefore, this study was conducted on 21 healthy, young subjects (10 subjects with planus foot type and 11 subjects with rectus foot type) to test whether different foot types yield distinguishable foot functions. New methods were developed to quantify biomechanical foot function during posture and comfortable cadence locomotion. The results of the study indicate that individuals with planus and rectus foot types show statistically significant differences in the biomechanical function of the foot.

Background— Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular disease. Monocytes display inflammatory and resident subsets and commit to specific functions in atherogenesis. In this study, we examined the hypothesis that HHcy modulates monocyte heterogeneity and leads to atherosclerosis. Methods and Results— We established a novel atherosclerosis-susceptible mouse model with both severe HHcy and hypercholesterolemia in which the mouse cystathionine β-synthase (CBS) and apolipoprotein E (apoE) genes are deficient and an inducible human CBS transgene is introduced to circumvent the neonatal lethality of the CBS deficiency ( Tg-hCBS apoE −/− Cbs −/− mice). Severe HHcy accelerated atherosclerosis and inflammatory monocyte/macrophage accumulation in lesions and increased plasma tumor necrosis factor-α and monocyte chemoattractant protein-1 levels in Tg-hCBS apoE −/− Cbs −/− mice fed a high-fat diet. Furthermore, we characterized monocyte heterogeneity in Tg-hCBS apoE −/− Cbs −/− mice and another severe HHcy mouse model ( Tg-S466L Cbs −/− ) with a disease-relevant mutation ( Tg-S466L ) that lacks hyperlipidemia. HHcy increased monocyte population and selective expansion of inflammatory Ly-6C hi and Ly-6C mid monocyte subsets in blood, spleen, and bone marrow of Tg-S466L Cbs −/− and Tg-hCBS apoE −/− Cbs −/− mice. These changes were exacerbated in Tg-S466L Cbs −/− mice with aging. Addition of l -homocysteine (100 to 500 μmol/L), but not l -cysteine, maintained the Ly-6C hi subset and induced the Ly-6C mid subset in cultured mouse primary splenocytes. Homocysteine-induced differentiation of the Ly-6C mid subset was prevented by catalase plus superoxide dismutase and the NAD(P)H oxidase inhibitor apocynin. Conclusion— HHcy promotes differentiation of inflammatory monocyte subsets and their accumulation in atherosclerotic lesions via NAD(P)H oxidase–mediated oxidant stress.

Understanding differences in arch structure may lend insight into the predilection for injury between genders, with increasing age, and between sides of a given subject.

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The arch height index measurement system device is reliable to use between testers while simplifying the measurement procedure for recording the arch height index. The arch height index may be helpful in identifying potential structural factors that predispose individuals to lower-extremity injuries.

ObjectivesStretch affects vascular smooth muscle cell proliferation and apoptosis, and several responsible genes have been proposed. We tested whether the expression of microRNA 21 (miR-21) is modulated by stretch and is involved in stretch-induced proliferation and apoptosis of human aortic smooth muscle cells (HASMCs).Methods and ResultsRT-PCR revealed that elevated stretch (16% elongation, 1 Hz) increased miR-21 expression in cultured HASMCs, and moderate stretch (10% elongation, 1 Hz) decreased the expression. BrdU incorporation assay and cell counting showed miR-21 involved in the proliferation of HASMCs mediated by stretch, likely by regulating the expression of p27 and phosphorylated retinoblastoma protein (p-Rb). FACS analysis revealed that the complex of miR-21 and programmed cell death protein 4 (PDCD4) participated in regulating apoptosis with stretch. Stretch increased the expression of primary miR-21 and pre-miR-21 in HASMCs. Electrophoretic mobility shift assay (EMSA) demonstrated that stretch increased NF-κB and AP-1 activities in HASMCs, and blockade of AP-1 activity by c-jun siRNA significantly suppressed stretch-induced miR-21 expression.ConclusionsCyclic stretch modulates miR-21 expression in cultured HASMCs, and miR-21 plays important roles in regulating proliferation and apoptosis mediated by stretch. Stretch upregulates miR-21 expression at least in part at the transcription level and AP-1 is essential for stretch-induced miR-21 expression.