Obesity in humans is associated with increased bone mass. Leptin, a hormone produced by fat cells, functions as a sentinel of energy balance, and may mediate the putative positive effects of body mass on bone. We performed studies in male C57Bl/6 wild type (WT) and leptin-deficient ob/ob mice to determine whether body mass gain induced by high fat intake increases bone mass and, if so, whether this requires central leptin signaling. The relationship between body mass and bone mass and architecture was evaluated in 9-week-old and 24-week-old WT mice fed a regular mouse diet. Femora and lumbar vertebrae were analyzed by micro computed tomography. In subsequent studies, slowly and rapidly growing ob/ob mice were injected in the hypothalamus with a recombinant adeno-associated virus containing the leptin gene (rAAV-lep) or a control vector, rAAV-GFP (green fluorescent protein). The mice were maintained on a regular control diet for 5 or 7 weeks and then subdivided into groups and either continued on the control diet or fed a high fat diet (45% of kcal from fat) for 8 weeks. In the WT mice, femoral and vertebral bone mass was positively correlated with body mass (Pearson’s r = 0.65–0.88 depending on endpoint). rAAV-lep therapy dramatically decreased body mass (−61%) but increased femur length. However, in the distal femur and lumbar vertebra, rAAV-lep therapy reduced cancellous bone volume/tissue volume, trabecular number and trabecular thickness, and increased trabecular spacing. The high fat diet increased body mass, irrespective of vector treatment. Total femur bone volume, length, cross-sectional volume, and cortical volume and thickness were increased in mice with increased body mass, independent of rAAV treatment. In the distal femur, increased body mass had no effect on cancellous architecture and there were no vector × body mass interactions. In WT mice, increased body mass resulted in increased (+33%) vertebral cancellous bone volume/tissue volume. Increased body mass had minimal independent effect on cancellous vertebral bone mass in ob/ob mice. Taken together, these findings suggest that increased body mass has a positive effect on femur cortical bone mass that is independent of leptin signaling.
In this study, the absorption properties of CO 2 in seven different solid amine absorbents were measured. The specific characteristics, such as absorption capacity, absorption/desorption rate, cyclic capacity, cycle decay effect, temperature of reaction in the absorber, and optimal conditions for the CO 2 absorption process were measured. This absorption process occurred at two temperaturesseither 296.15 or 313.15 Kswhile the desorption process temperature was raised to 348.15 K. The solid amines (TEPAN and E-100AN) demonstrated higher cyclic capacity than others under these conditions. Our testing showed high reproducibility for the CO 2 capture of TEPAN and E-100AN in measuring their cyclic capacity. Diminished cyclic capacities were noted for the MEA and 194B materials, with measured drops at the third cycle of about 16.17% and 15.79% lower than those in the first cycle, respectively.
The physical solubility and diffusivity of N 2 O and CO 2 in aqueous sodium glycinate (SG) solutions of various concentrations (1.0-3.5 kmol/m 3 ) and temperatures (303.15-323.15 K) were reported. The kinetics of the reaction between CO 2 and SG has been studied using absorption data measured by a wetted-wall column apparatus at various temperatures and concentrations. The second-order rate constant of CO 2 with SG was determined to be k 2 (m 3 kmol -1 s -1 ) ) 1.95 × 10 13 exp(-7670/T), where T is the absolute temperature (given in Kelvin). The activation energy for the reaction of CO 2 with SG was calculated to be 63.8 kJ/mol.
A recent genome wide association study (GWAS) indentified a significant association between rs2294008 (C > T) polymorphism in prostate stem-cell antigen (PSCA) and increased risk of gastric cancer in Japanese and Korean populations. The aim of this study was to determine whether rs2294008 polymorphism is associated with risk of gastric cancer in a Korean population. We conducted a large-scale case-control study of 3,245 gastric cancer patients and 1,700 controls. The frequencies of the CC, CT, and TT genotypes of rs2294008 polymorphism were 17.8%, 49.9%, and 32.3% in the gastric cancer patients; and 24.4%, 48.1%, and 27.5% in the controls, respectively. We found that the CT and TT genotypes were associated with a significantly increased risk of gastric cancer (OR(CT) = 1.50, 95% confidence intervals, 95% CI: 1.28-1.76; OR(TT) = 1.71, 95% CI: 1.43-2.04), compared with the CC genotype. Further, stratified by tumor location and histological type, the effect of the rs2294008 T allele was larger in cardia (OR(TT) = 2.62, 95% CI = 1.42-4.85) than non-cardia (OR(TT) = 1.67, 95% CI = 1.40-2.00), in diffuse-type (OR(TT) = 2.00, 95% CI: 1.55-2.59) than in intestinal-type (OR(TT) = 1.51, 95% CI: 1.22-1.86). Our study showed that rs2294008 in the PSCA gene was associated with increased risks of gastric cancer in a Korean population, suggests that rs2294008 might play an important role in gastric carcinogenesis.
The physicochemical properties of aqueous sodium glycinate solution such as density, viscosity, surface tension, alkalinity, and pH were measured over a wide range of mass fraction (0.1 to 0.5) of sodium glycinate and at T ) (303.15 to 353.15) K. The measured data were correlated with standard equations, and parameters were reported along with average absolute deviations.
A recent genome-wide association study (GWAS) identified new susceptibility single-nucleotide polymorphisms (SNPs) rs13361707 (PRKAA1 and PTGER4 gene on 5p13.1) and rs9841504 (ZBTB20 gene on 3q13.31) that were significantly associated with non-cardia gastric cancer. The aim of this study was to determine whether rs13361707 and rs9841504 polymorphisms are associated with the risk of gastric cancer in a Korean population. We conducted a large-scale case-control study of 3245 gastric cancer patients and 1700 controls. The allele frequencies for rs13361707 C and rs9841504 G were 53.5% and 18.3% among gastric cancer cases, compared with 47.1% and 17.2% among controls, respectively. We found that rs13361707 TC and CC genotypes were associated with increased risk for gastric cancer (odds ratios [OR] = 1.29; 95% confidence interval [CI] = 1.11-1.51 for TC vs. TT and 1.68; 1.41-2.01 for CC vs. TT). However, we found no significant association between rs9841504 and gastric cancer risk (OR = 1.11; 0.97-1.28 for CG vs. CC; OR = 1.09; 0.77-1.53 for GG vs. CC). We observed no significant interactions between rs13361707 and rs9841504 polymorphisms and age, gender, smoking habit, alcohol consumption, and clinicopathologic characteristics such as anatomical tumor location and histological type. Our study showed that the rs13361707 polymorphism was associated with increased risk of gastric cancer in a Korean population. This finding provides further evidence that genetic variant of PRKAA1 and PTGER4 genes may contribute to the gastric carcinogenesis. However, we found no association between rs9841504 and gastric cancer risk.
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