ABSTRACT
Objective To study the effect of negative polarity electret on the dielectric properties and structure of insulin, and to observe the influence of electrostatic field on the hypoglycemic effect of insulin. Methods Negative polarity electrets of –500, –1 000 and –1 500 V were prepared using polypropylene film by a gate voltage corona charging system, and were used to treat insulin, respectively. The equivalent surface potential of each electret within 48 h was measured by compensation method. The relationship between the polarization of insulin and the electrostatic field was measured by the dielectric constant d33. The influence of the electrostatic field on the molecular structure of insulin was examined by nuclear magnetic resonance and gel electrophoresis. Insulin exposed to –500, –1 000 and –1 500 V negative polarity electret for 12 h was injected into the diabetic rats, and then the hypoglycemic effect of insulin were observed. Results The potential differences between the two sides of insulin solution effected by negative polarity electrets with different surface potentials were exponentially increased within 0-4 h and gradually became constant at 4-48 h. Compared with the insulin patch treated by non-electret electrostatic field, the d33 values of insulin patch effected by –500, –1 000 and –1 500 V electret for 12 h were increased by 14.7 times, 26.7 times and 45.0 times, respectively, and all tended to be stable after 12 h. The spatial structure of insulin exposed to electrostatic field did not change, but the hydrogen bond content of most perssad was decreased; the proportion of monomers of the insulin was increased, and the main structures of the insulin were monomers and dimers. Compared with the electret-free insulin treatment group, the blood glucose content of diabetic rats treated with the –500 V and –1 000 V negative polarity electrets insulin for 8 h were decreased by 50.9% and 22.1%, respectively (P<0.05). Conclusion Negative polarity electret can further improve the hypoglycemic effect of insulin.
ABSTRACT
Objective To search for the potential plasma biomarkers for patients with psoriasis vulgaris by metabonomics technology based on nuclear magnetic resonance 1H spectroscopy (1HNMR), and to explore the related metabolic pathway. Methods 1HNMR technique was applied to examine the plasma samples from 10 patients with psoriasis vulgaris and 12 healthy volunteers. The data were analyzed for pattern recognition using principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The differential metabolites in plasma between patients psoriasis vulgaris and healthy volunteers were analyzed, and the metabolic pathways were constructed according to the changes of the differential metabolites. Results Pattern recognition analysis had a satisfactory discriminating and predicting performance. Compared with healthy volunteers, the levels of very low density lipoprotein (VLDL), low density lipoprotein (LDL), lipids, leucine, isoleucine, valine, β-hydroxybutyrate, lactate, alanine, arginine, N-acetylglycoproteins, acetoacetate, glutamate, pyruvate, glutamine, citrate, creatine, creatinine, glucose, aspartate and phenylalanine in plasma of patients with psoriasis vulgaris were greatly increased. Conclusion Our results suggest that patients with psoriasis vulgaris have disorders of lipid metabolism, glucose metabolism and amino acid metabolism, accompanied by inflammation and functional damage to the liver and kidney, which may improve our understanding of the pathogenesis of psoriasis vulgaris.