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Fibroblast growth factor‐23 (FGF23) is a hormonal regulator of circulating phosphate and vitamin D levels. Recent investigations revealed that besides a key role in the pathogenesis of calcium–phosphorus disorders, in some patients FGF23 may be an indicator of cardiovascular complications. As a ‘hormone‐like’ factor, it may also be involved in some metabolic processes, especially in the metabolism of glucose and fat. Its potential contribution to metabolic syndrome (MS) development has not been confirmed yet. Objective The study was to examine the possible correlations between FGF23 serum levels and body composition, blood pressure and selected parameters of glucose, insulin and fat metabolism in adolescents with simple obesity. Patients and design In 68 (35 female) adolescents (mean age 13·9 years) with simple obesity [mean BMI SDS 4·9 (95% CI 4·4–5·4)], the levels of FGF23, total cholesterol, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol and triglycerides were measured. Standard oral glucose tolerance tests were performed with the assessment of fasting and after 120′ postload glucose and insulin levels; the insulin resistance index HOMA‐IR was calculated. Results Regardless of gender, there was a significant inverse correlation between FGF23 and fasting insulin level (r = ?0·3), as well as HOMA‐IR (r = ?0·29). Multiple regression model showed the independent association between FGF23 and HOMA‐IR. Conclusion FGF23 seems to be a novel factor contributing to insulin sensitivity. Further investigations are needed to define its role in the development of MS.  相似文献   
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Elite athletes have a higher prevalence of exercise-induced bronchoconstriction than the general population. The pathogenesis of exercise-induced bronchoconstriction is not fully elucidated. Increasing evidence suggests that airway inflammation plays a major role in the immunopathogenesis of exercise-induced bronchoconstriction. The aim of our review is to discuss existing evidence and to present a new, modified inflammatory hypothesis of exercise-induced bronchoconstriction. Exercise alters the number and function of circulating immune cells. Episodes of upper respiratory symptoms in elite athletes do not follow the usual seasonal patterns. Moreover, they have an unusual short-term duration, which suggests a non-infectious etiology. If the pro-inflammatory response to exercise has the potential to induce symptoms that mimic respiratory tract infection, it definitely up-regulates pro-inflammatory cytokine expression in the airways. We can conclude that exercise up-regulates airway cytokine expression in a way that favors inflammation and allergic reactions in bronchi and lowers the threshold for bronchoconstriction to different stimuli like cool, dry air, allergens, and pollutants.  相似文献   
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Primary open-angle glaucoma (POAG) is one of the most common types of glaucoma. Glaucoma is a progressive neuropathy of the optic nerve with characteristic visual area disorders. The aim of this study was to assess the correlations between rheological parameters of blood and other parameters such as: intraocular pressure, visual acuity, angular breadth of the aqueous fluid eluvium, visual area and arterial hypertension. The examined group was comprised of 54 patients with POAG. Out of this group two subgroups was separated: I subgroup of 24 patients without hypertensive and II subgroup of 30 patients with chronic hypertensive disease. The control group was comprised of 40 healthy subjects. Erythrocyte aggregation and deformability analysis were determined using LORCA. From the results we concluded that rheological disorders such as enhanced erythrocyte aggregation or significantly decreased erythrocyte deformability occur in patients with POAG. Additionally, it revealed a significant relation between the duration of hypertension and an increased erythrocyte aggregation index (r = +0.27 p < 0.005) along with decreased deformability (r = -0.37 p < 0.001), where the decrease in deformability correlated with the severity of hypertonic retinal angiopathy (r = -0.30 p < 0.05). All these disorders may result in decreased blood flow to the optic nerve, which contributes towards the development of neuropathy.  相似文献   
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