Liver: An alarm for the heart?

Background/Aims: Fatty liver (FL) and coronary artery disease (CAD) have several risk factors in common, which are usually considered to account for their frequent coexistence. The independent association between FL and angiographic CAD was assessed in this case-control study by considering the contribution of their shared risk factors. Methods: Three hundred and seventeen adult patients who underwent elective coronary angiography (CAG) were recruited immediately after CAG and classified into either of the two groups A (normal or mildly abnormal CAG; n = 85) or B (clinically relevant CAD; n = 232). A liver sonography was performed on the same day as CAG. Results: The groups were significantly different in terms of gender, fasting blood glucose, low-density lipoproteins, diabetes (DM), hypertension and FL. In binary logistic regression, FL was the strongest independent predictor of CAD P < 0.001, odds ratio (OR) = 8.48%, 95% confidence interval (CI) = 4.39-16.40, followed by DM (P = 0.002, OR = 2.94) and male gender (P = 0.014, OR = 2.31). This pattern of associations did not change after clinically significant variables (waist-to-hip ratio, body mass index, triglycerides and high-density lipoproteins) were added to analysis. Conclusion: Fatty liver seems to be a strong independent alarm for the presence of significant CAD. © 2007 Blackwell Munksgaard

Upper limb impairments associated with spasticity in neurological disorders

<p>Abstract</p> <p>Background</p> <p>While upper-extremity movement in individuals with neurological disorders such as stroke and spinal cord injury (SCI) has been studied for many years, the effects of spasticity on arm movement have been poorly quantified. The present study is designed to characterize the nature of impaired arm movements associated with spasticity in these two clinical populations. By comparing impaired voluntary movements between these two groups, we will gain a greater understanding of the effects of the type of spasticity on these movements and, potentially a better understanding of the underlying impairment mechanisms.</p> <p>Methods</p> <p>We characterized the kinematics and kinetics of rapid arm movement in SCI and neurologically intact subjects and in both the paretic and non-paretic limbs in stroke subjects. The kinematics of rapid elbow extension over the entire range of motion were quantified by measuring movement trajectory and its derivatives; i.e. movement velocity and acceleration. The kinetics were quantified by measuring maximum isometric voluntary contractions of elbow flexors and extensors. The movement smoothness was estimated using two different computational techniques.</p> <p>Results</p> <p>Most kinematic and kinetic and movement smoothness parameters changed significantly in paretic as compared to normal arms in stroke subjects (p < 0.003). Surprisingly, there were no significant differences in these parameters between SCI and stroke subjects, except for the movement smoothness (p ≤ 0.02). Extension was significantly less smooth in the paretic compared to the non-paretic arm in the stroke group (p < 0.003), whereas it was within the normal range in the SCI group. There was also no significant difference in these parameters between the non-paretic arm in stroke subjects and the normal arm in healthy subjects.</p> <p>Conclusion</p> <p>The findings suggest that although the cause and location of injury are different in spastic stroke and SCI subjects, the impairments in arm voluntary movement were similar in the two spastic groups. Our results also suggest that the non-paretic arm in stroke subjects was not distinguishable from the normal, and might therefore be used as an appropriate control for studying movement of the paretic arm.</p

Muscle and reflex changes with varying joint angle in hemiparetic stroke

<p>Abstract</p> <p>Background</p> <p>Despite intensive investigation, the origins of the neuromuscular abnormalities associated with spasticity are not well understood. In particular, the mechanical properties induced by stretch reflex activity have been especially difficult to study because of a lack of accurate tools separating reflex torque from torque generated by musculo-tendinous structures. The present study addresses this deficit by characterizing the contribution of neural and muscular components to the abnormally high stiffness of the spastic joint.</p> <p>Methods</p> <p>Using system identification techniques, we characterized the neuromuscular abnormalities associated with spasticity of ankle muscles in chronic hemiparetic stroke survivors. In particular, we systematically tracked changes in muscle mechanical properties and in stretch reflex activity during changes in ankle joint angle. Modulation of mechanical properties was assessed by applying perturbations at different initial angles, over the entire range of motion (ROM). Experiments were performed on both paretic and non-paretic sides of stroke survivors, and in healthy controls.</p> <p>Results</p> <p>Both reflex and intrinsic muscle stiffnesses were significantly greater in the spastic/paretic ankle than on the non-paretic side, and these changes were strongly position dependent. The major reflex contributions were observed over the central portion of the angular range, while the intrinsic contributions were most pronounced with the ankle in the dorsiflexed position.</p> <p>Conclusion</p> <p>In spastic ankle muscles, the abnormalities in intrinsic and reflex components of joint torque varied systematically with changing position over the full angular range of motion, indicating that clinical perceptions of increased tone may have quite different origins depending upon the angle where the tests are initiated.</p> <p>Furthermore, reflex stiffness was considerably larger in the non-paretic limb of stroke patients than in healthy control subjects, suggesting that the non-paretic limb may not be a suitable control for studying neuromuscular properties of the ankle joint.</p> <p>Our findings will help elucidate the origins of the neuromuscular abnormalities associated with stroke-induced spasticity.</p

Decreased Circulating Endothelial Progenitor Cell Levels and Function in Patients with Nonalcoholic Fatty Liver Disease

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is associated with advanced atherosclerosis and a higher risk of cardiovascular disease. Increasing evidence suggests that injured endothelial monolayer is regenerated by circulating bone marrow derived-endothelial progenitor cells (EPCs), and levels of circulating EPCs reflect vascular repair capacity. However, the relation between NAFLD and EPC remains unclear. Here, we tested the hypothesis that patients with nonalcoholic fatty liver disease (NAFLD) might have decreased endothelial progenitor cell (EPC) levels and attenuated EPC function. METHODS AND RESULTS: A total of 312 consecutive patients undergoing elective coronary angiography because of suspected coronary artery disease were screened and received examinations of abdominal ultrasonography between July 2009 and November 2010. Finally, 34 patients with an ultrasonographic diagnosis of NAFLD, and 68 age- and sex-matched controls without NAFLD were enrolled. Flow cytometry with quantification of EPC markers (defined as CD34(+), CD34(+)KDR(+), and CD34(+)KDR(+)CD133(+)) in peripheral blood samples was used to assess circulating EPC numbers. The adhesive function, and migration, and tube formation capacities of EPCs were also determined in NAFLD patients and controls. Patients with NAFLD had a significantly higher incidence of metabolic syndrome, previous myocardial infarction, hyperuricemia, and higher waist circumference, body mass index, fasting glucose and triglyceride levels. In addition, patients with NAFLD had significantly decreased circulating EPC levels (all P<0.05), attenuated EPC functions, and enhanced systemic inflammation compared to controls. Multivariate logistic regression analysis showed that circulating EPC level (CD34(+)KDR(+) [cells/10(5) events]) was an independent reverse predictor of NAFLD (Odds ratio: 0.78; 95% confidence interval: 0.69-0.89, P<0.001). CONCLUSIONS: NAFLD patients have decreased circulating EPC numbers and functions than those without NAFLD, which may be one of the mechanisms to explain atherosclerotic disease progression and enhanced cardiovascular risk in patients with NAFLD

Review of natural fibre-reinforced hybrid composites

Natural fibre-reinforced hybrid composites which contain one or more types of natural reinforcement are gaining increasing research interest. This paper presents a review of natural fibre-reinforced hybrid composites. Both thermoplastic and thermoset composites reinforced by hybrid/synthetic fibres or hybrid/hybrid fibres are reviewed. The properties of natural fibres, the properties and processing of composites are summarised