3 resultados para 588.1


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The electrochemistry of phenol and 4-tert-butyl-phenol is described in [C(2)mim][NTf2] and [C(4)mpyrr][NTf2] ionic liquids. Oxidation of phenol and phenolate is observed at E-p(a) = +1.64 and +0.24 V vs. Ag in both ionic liquids. On the cathodic sweep at a potential of -2.05 P 02 V vs. Ag under an oxygen atmosphere, the production of O-2(2-) dianions triggers the formation of phenolate anions which undergo chemical oxidation to the phenoxyl radical. The phenoxyl radical then reacts with the [NTf2](-) anion of the ionic liquid to form the corresponding phenyl triflate molecule. (c) 2005 Elsevier B.V. All rights reserved.

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PURPOSE: To evaluate serum soluble Flt-1 (sFlt-1) in age-related degeneration (AMD) patients.

DESIGN: Case control study.

METHODS: Fifty-six non-AMD participants, fifty-three early AMD patients and ninety-seven neovascular AMD patients from Belfast in Northern Ireland. Serum samples were collected from each patient. Serum sFlt-1 was measured by human sVEGFR1/sFlt-1 ELISA kit. The results were analyzed by Excel and SPSS.

RESULTS: Serum sFlt-1 concentration of non-AMD, early AMD, and neovascular AMD were 90.8±2.9 pg/mL (±SEM), 88.2±2.6 pg/mL and 79.9±2.2 pg/mL. sFlt-1 from neovascular AMD patients was significantly decreased compared to non-AMD and early AMD patients (ANOVA, p<0.01). For each 10 point increase in sFlt-1, the odds for having neovascular AMD compared with non-AMD and neovascular AMD decreases by 27.8% OR=0.722 (95% CI: 0.588-0.888, p=0.002) and 27.0% OR=0.730 (95% CI: 0.594-0.898, p=0.003), respectively. In patients over 73 years of age, serum sFlt-1 <80 pg/mL was associated with a >6-fold higher risk of neovascular AMD.

CONCLUSIONS: Reduced serum sFlt-1 differentiates those patients with neovascular AMD from both early AMD and non-AMD participants. In those aged over 73, serum sFlt <80 pg/mL seems to indicate a particularly high risk of neovascular AMD. Our results indicate serum sFlt-1 could be a biomarker for development of neovascular AMD.

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PURPOSE: Inadequately corrected refractive error is the leading cause of visual disability among children in China; inaccurate spectacles are a potential cause. The prevalence and visual impact of spectacle inaccuracy were studied among rural, secondary-school children, to determine the optimal timing for updating of refraction. METHODS: A random sample of children from years 1 and 2 in all junior and senior high schools in Fuyang Township, Guangdong Province, underwent ocular examination. All children who reported wearing glasses received cycloplegic refraction, vision assessment, and measurement of current spectacles. RESULTS: Among 3226 examined children, 733 (22.7%) reported owning spectacles. Refractive error and spectacle power were assessed for 588 (80.2%) children. They had a mean age of 15.0 +/- 1.6 years; 70.2% were girls, 83.3% had more than -1.5 D of myopia, and 17.9% had presenting vision < or = 6/12 in the better eye. The glasses of 48.8% of children were inaccurate by > or = 1 D; inaccuracy was > or = 2 D in 17.7%. Children with inaccurate glasses (> or = 1 D) had presenting vision in the better eye significantly (P < 0.001) worse than that of children with accurate glasses, and 30.3% had presenting acuity < or = 6/12. In multivariate models, younger age (P = 0.004), more myopic refractive error (P < 0.001), and having glasses > or = 1 year old (P = 0.04) were associated with inaccurate spectacles. DISCUSSION: Inaccurate spectacles are common and are associated with significant visual impairment among children in rural China. Reducing outdated glasses could lessen the visual burden, although refractive services may have to be offered on an annual basis for optimal benefit.