Objective: Recently, a subtype of obesity characterized as a metabolically healthy but obese (MHO) individual has been identified. However, limited data are available on these MHO individuals' metabolic and inflammatory profiles, and the effect of weight loss on these profiles. We investigated metabolic and inflammatory markers in MHO women to determine the effects of a 12-week weight loss on those markers. Subjects: One hundred and twenty-nine overweight-obese Korean women participated for 12 weeks in a clinical intervention study involving a 300 kcal/day intake reduction. The subjects were divided into two groups: MHO and metabolically abnormal obese (MAO) individuals. Methods: Computed tomography was performed. C-reactive protein (CRP), interkeukin-6 (IL-6) and oxidized low-density lipoprotein (LDL), as well as blood lipids, glucose and insulin concentrations were determined at baseline and after weight loss. Results: At baseline, plasma CRP (Po0.001), IL-6 (Po0.05) and oxidized LDL (Po0.001) levels were significantly lower in the MHO group than in the MAO group. Visceral fat at L1 (Po0.005) and visceral fat at L4 (Po0.001) were significantly lower in the MHO group than in the MAO group. The treatment induced weight loss averaging 3.11% of initial body weight, and the degree of weight loss between the two groups was similar. Visceral fat at L1 and L4 was reduced from its initial values by 3.2 and 5.4%, respectively, after weight loss. The levels of CRP (Po0.05) and oxidized LDL (Po0.01) were significantly reduced in the MAO group after the 12-week weight loss, whereas these effects were not seen in the MHO group. Conclusions: Our results showed that MHO individuals exhibited lower visceral fat accumulation and more favorable metabolic and inflammatory states than MAO individuals. After a 12-week weight loss program, significant reductions in blood lipids, CRP and oxidized LDL levels were observed in MAO individuals. However, there was no measurable effect of weight loss on lipid profiles and inflammation in MHO individuals, indicating differing effects of weight loss on these markers between MAO and MHO groups.

Objective: The purpose of this study was to determine whether common single nucleotide polymorphisms (SNPs) at the adiponectin (ADIPOQ) locus influence changes in circulating adiponectin and the features of insulin resistance in response to a weight loss intervention. Subjects: In total, 294 nondiabetic/overweight-obese Koreans participated in a clinical intervention study lasting 12 weeks involving a caloric reduction of À300kcal/day. Methods: Plasma adiponectin, blood lipids, glucose and insulin concentrations were measured at baseline and after weight loss. Insulin resistance was estimated by homeostasis model assessment insulin resistance (HOMA-IR) derived from fasting glucose and insulin concentrations. We genotyped for three SNPs, 45T4G, 276G4T and À11377C4G. Results: At baseline, HOMA-IR was significantly higher in GG homozygotes than in carriers of the T allele at SNP276G4T of the adiponectin gene (Po0.05). With regard to SNP45T4G and SNP À11377C4G, we did not find any genotype related differences in baseline levels of HOMA-IR and adiponectin. In the 45/276 haplotype test, homozygous for the TG haplotype had significantly lower concentrations of plasma adiponectin (Po0.05). After the 12-week weight loss intervention, the significant decreases in HOMA-IR (Po0.001) and increases in adiponectin (Po0.01) were observed in GG homozygotes at SNP276, which were not shown in carriers of the T allele. Furthermore, there was a significant difference in the decreases in HOMA-IR between the GG homozygotes and carriers of the T allele at SNP276 (Po0.05). Regarding SNP45T4G and SNP À11377C4G, there was no association between SNP45T4G and SNP À11377C4G and decreases in HOMA-IR. In the 45/276 haplotype test, there was a significant difference in changes of adiponectin levels among those with different haplotype combinations (Po0.05). Conclusion: The SNP276G4T of the ADIPOQ gene is associated with different responses of circulating adiponectin and insulin resistance to mild weight loss in overweight-obese subjects.

Understanding the mechanism of carbon oxidation is important for the successful modeling of diesel particulate filter regeneration. Characteristics of soot oxidation were investigated with carbon black (Printex-U). A flow reactor system that could simulate the condition of a diesel particulate filter and diesel exhaust gas was designed. Kinetic constants were derived and the reaction mechanisms were proposed using the experimental results and a simple reaction scheme, which approximated the overall oxidation process in TPO as well as CTO. From the experiments, the apparent activation energy for carbon oxidation with NO 2 -O 2 -H 2 O was determined to be 40±2 kJ/mol, with the first order of carbon in the range of 10~90% oxidation and a temperature range of 250~500 o C. This value was exceedingly lower than the activation energy of NO 2 -O 2 oxidation, which was 60±3 kJ/mol. When NO 2 exists with O 2 and H 2 O, the reaction rate increases in proportion to NO 2 . It increases nonlinearly with O 2 or H 2 O concentration when the other two oxidants are fixed.

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