ABSTRACT
Liquid isopropanol, n-butanol, and n-decane are combustible organic compounds that are frequently used in theoretical and experimental researches on fuel combustion. In this work, the temperature-dependent optical constants of liquid isopropanol, n-butanol, and n-decane in the region 500-5500 cm-1 at ambient pressure are measured using the combined ellipsometry-transmission method. In the combined method, the optical constants are first measured by a modified ellipsometry method, and then the absorption indices for weak absorption regions are obtained by the transmission method using the refractive indices measured by the modified ellipsometry method. The refractive indices of liquid isopropanol, n-butanol, and n-decane are within the range from 1.3 to 1.45 in the studied wavelength and temperature region. The absorption indices of these liquids range from 10-5 to 10-1. In the temperature range studied, the refractive indices decrease with increasing temperature in an approximately linear manner, but the effects of the temperature on the absorption indices are much smaller. The characteristic wavenumbers of the main absorption peaks are consistent with the vibrational frequencies of major functional groups.
ABSTRACT
BACKGROUND: Nowadays, intensive insulin treatment has been widely used in type 2 diabetics who have poor control of blood glucose, to reduce the risk of chronic complications of diabetes. Recently, some scholars have paid more attention to the pivotal role of inflammation involved in type 2 diabetes and its complications. Monocyte chemoattractant protein-1 (MCP-1) and intercellular adhesion molecule-1 (ICAM-1), which are two important inflammatory chemokines, have been documented to participate in the onset and development of type 2 diabetes and its complications, such as diabetic nephropathy (DN). DESIGN: In the current study, we recruited 30 type 2 diabetics with microalbuminuria to be treated with multiple insulin injections daily for 2 weeks. Random spot urine samples (corrected for creatinine-Cr) were collected for the examination of urinary MCP-1, ICAM-1 and albumin (Alb) levels before and after the intensive insulin therapy. Changes in their levels were observed to test the hypothesis that type 2 diabetes with microalbuminuria is associated with elevated urinary concentrations of MCP-1 and ICAM-1, and intensive insulin therapy can result in a decline of Alb by reducing the inflammatory reaction. RESULTS: The urinary MCP-1/Cr and urinary ICAM-1/Cr ratios in type 2 diabetic patients with microalbuminuria were much higher than those in normal controls, and intensive insulin treatment could decrease significantly the urinary MCP-1/Cr, ICAM-1/Cr and Alb/Cr ratios in type 2 diabetics with microalbuminuria. CONCLUSION: Intensive insulin treatment may protect against renal injury in early DN by reducing the urinary MCP-1 and ICAM-1 excretions.
