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Potential antiinflammatory and antioxidant effects were recently ascribed to naturally occurring micronutrients. The extent and magnitudes of their differential effects on the metabolic syndrome (MetS) are still unknown. We examined the association between serum antioxidant status and MetS. NHANES 2001-2006 cross-sectional data among adults aged 20-85 y were analyzed (n = 3008-9099). MetS was defined with the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) and also by elevated homeostatic model assessment insulin resistance (HOMA-IR), C-reactive protein (CRP) and hyperuricemia. Serum antioxidants included retinol, retinyl esters, carotenoids [α-carotene, β-carotene (cis+trans), β-cryptoxanthin, lutein+zeaxanthin, total lycopene], vitamin E, and vitamin C. MetS (NCEP ATP III) prevalence in U.S. adults was 32.0% among men and 29.5% among women. Adults with MetS had consistently lower serum carotenoid concentrations compared with those without MetS, even after controlling for total cholesterol and TG among other potential confounders. Vitamin E had no significant relationship with MetS in the full multiple logistic regression model, whereas retinol+retinyl esters were inversely related to MetS among men only. The latter were also inversely related to elevated CRP and positively associated with hyperuricemia. Vitamin C exhibited a similar pattern to serum carotenoids with an inverse linear association with MetS (binary), HOMA-IR, and hyperuricemia. Future intervention studies of dietary and lifestyle change must be conducted to assess the utility of modifying serum antioxidant concentrations, especially carotenoids, given their suboptimal levels among U.S. adults with MetS, for the prevention of type 2 diabetes and various cardiovascular endpoints.  相似文献   
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In subjects with previous preeclampsia, differences in cardiovascular and/or blood biochemical parameters are present in the nonpregnant state, and a simultaneous assessment of multiple derived indices better differentiates between women with or without previous preeclampsia. We examined 18 previous preeclamptic and 50 previous uncomplicated pregnancies, ≈16 months postpartum. Cardiovascular assessment included the following: (1) systemic hemodynamics and mechanics (Doppler echocardiography, tonometry, and oscillometric sphygmomanometry); (2) endothelial function (plethysmography); (3) left ventricular properties (echocardiography); and (4) blood biochemical analyses. Compared to women with previous uncomplicated pregnancies, previous preeclamptics had higher mean (80±1 versus 86±3 mm Hg; P=0.04) and diastolic (64±1 versus 68±2 mm Hg; P=0.04) pressures and total vascular resistance (1562±37 versus 1784±114 dyne · s/cm(5); P=0.03). Systolic blood pressure, arterial compliance, and left ventricular properties were not different. Although heart-to-femoral pulse wave velocity was not different, heart-to-brachial pulse wave velocity tended to be faster in previous preeclamptics (374±8 versus 404±20 cm/s; P=0.06). Stress-induced increase in forearm blood flow was less in previous preeclamptics (245%±21% versus 136%±22%; P=0.01), indicating impaired endothelial function. No significant differences were observed in markers of endothelial activation, dyslipidemia, or oxidative stress; previous preeclamptics tended to have higher glucose level (58.7±1.9 versus 95±5.2 mg/dL; P=0.06). Logistic regression analysis indicated that a simultaneous evaluation of multiple derived indices better discriminated between the 2 groups. The differences in the previous preeclamptic group are in directions known to be associated with greater cardiovascular disease risk later in life.  相似文献   
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Sickle cell anaemia (SCA) is a devastating genetic blood disorder leading to chronic anaemia, impaired cerebrovascular dilatory capacity and cerebral infarctions. Our aim was to assess the relationship between microstructural properties of the white matter (WM) and both cerebrovascular reactivity (CVR) and cerebral blood flow, as well as the effects of hydroxycarbamide on these relationships. Our results demonstrate that mean CVR was increased in hydroxycarbamide-treated patients compared to untreated patients. Moreover, untreated SCA patients had increased skew and kurtosis of mean diffusivity histograms in the WM compared to hydroxycarbamide-treated patients and healthy age-matched controls, indicating disruption of WM integrity. Regression analysis of CVR and WM mean diffusivity (MD) revealed a significant linear relationship between CVR and MD histogram skew and kurtosis in healthy controls, but not in either of the two SCA groups. These findings suggest that patients treated with hydroxycarbamide possess white matter MD histogram parameters which more closely resemble those of healthy controls.  相似文献   
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Taylor  M.J.  Vandewouw  M.M.  Young  J.M.  Card  D.  Sled  J.G.  Shroff  M.M.  Raybaud  C. 《Neuroradiology》2018,60(10):1063-1073
Neuroradiology - Brain metabolites show very rapid maturation over infancy, particularly following very preterm (VPT) birth, and can provide an index of brain injury. The utility of magnetic...  相似文献   
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