RESUMEN
Elderly individuals with non-dipper hypertension are at high risk of cardiovascular disease because of increased stiffness of peripheral arteries. Since, vitamin D deficiency is prevalent in elderly Chinese. We examined whether reduced plasma levels of 25-hydroxyvitamin D [25(OH)D] may help promote this stiffness.Hypertensive patients at least 60 years old without history of peripheral arterial disease at our hospital were retrospectively divided into dipper and non-dipper groups according to the results of 24-hour ambulatory blood pressure monitoring. Plasma levels of 25(OH)D were measured by enzyme immunoassay. Peripheral arterial stiffness was measured based on the cardio-ankle vascular index (CAVI).Of the 155 patients enrolled, 95 (61.3%) were diagnosed with non-dipper hypertension and these patients had significantly lower plasma levels of 25(OH)D than the 60 patients with dipper hypertension (19.58â±â5.97 vs 24.36â±â6.95ânmol/L, Pâ<â.01) as well as significantly higher CAVI (8.46â±â1.65 vs 7.56â±â1.08âm/s, Pâ<â.01). Vitamin D deficiency was significantly more common among non-dipper patients (57.9% vs 31.7%, Pâ<â.01). Multivariate regression showed that age and 25(OH)D were independently related to CAVI, with each 1-ng/ml decrease in 25(OH)D associated with a CAVI increase of +0.04âm/s.Non-dipper hypertension is associated with vitamin D deficiency and reduced plasma levels of 25(OH)D. The latter may contribute to stiffening of peripheral arteries, increasing the risk of cardiovascular disease.
Asunto(s)
Hipertensión/sangre , Rigidez Vascular , Vitamina D/análogos & derivados , Anciano , Pueblo Asiatico , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Vitamina D/sangreRESUMEN
A simple hydrothermal method was developed for the synthesis of uniform single-crystal ß-MnO(2) nanorods only using potassium permanganate and sodium nitrite in acidic solution, without any seed or template. The as-prepared ß-MnO(2) nanorods have the average diameter of 300±20 nm and a length up to 1.2±0.2 µm. Moreover, the effects of pH, temperature, and reactant molar ratios on the morphology of the final product were studied in detail. In addition, the catalytic ability of the as-prepared ß-MnO(2) nanorods was tested for the electrooxidation of nitrite. The resulting sensor showed a wide linear range from 0.29 µM to 26.09 mM (R=0.9986), high sensitivity (1.21 µA mM(-1), S/N=3), low detection limit (0.29 µM), and fast response (less than 5 s).
Asunto(s)
Calor , Compuestos de Manganeso/síntesis química , Nanotubos/química , Óxidos/síntesis química , Nitrito de Sodio/análisis , Nitrito de Sodio/química , Compuestos de Manganeso/química , Ensayo de Materiales , Óxidos/química , Permanganato de Potasio/químicaRESUMEN
Spermine-graft-dextran (Spe-g-Dex) copolymer was synthesized and used as a non-covalent coating for the separation of proteins and neurotransmitters by capillary electrophoresis. The coating was obtained via flushing the capillary with 1.0% Spe-g-Dex copolymer solution for 2min. Electroosmotic flow (EOF) was strongly suppressed, ranging from -1.60x10(-9) to 3.65x10(-9)m(2)V(-1)s(-1). Effect of experimental conditions, such as the copolymer concentration, the concentration and pH of the background electrolyte (BGE), on the Spe-g-Dex coating was investigated. Separation of lysozyme, cytochrome c, ribonuclease A and alpha-chymotrypsinogen yielded high separation efficiencies ranging from 141000 to 303000plates/m and recoveries from 85.4% to 98.3% at pH 4.0 (284.0mM sodium acetate-acetic acid buffer, I=50mM). Run-to-run repeatabilities and day-to-day, and capillary-to-capillary reproducibilities were all below 1.7%. In addition, Spe-g-Dex coating allowed the successful separation of five neurotransmitters, 5-hydroxytryptamine, dopamine, epinephrine, isoprenaline, dobuamine at pH 4.0 with high separation efficiencies of 290000-449000plates/m.