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761.
Acute and chronic kidney lesions induce an increase in A Disintegrin And Metalloproteinase domain 17 (ADAM17) that cleaves several transmembrane proteins related to inflammatory and fibrotic pathways. Our group has demonstrated that renal ADAM17 is upregulated in diabetic mice and its inhibition decreases renal inflammation and fibrosis. The purpose of the present study was to analyze how Adam17 deletion in proximal tubules affects different renal structures in an obese mice model. Tubular Adam17 knockout male mice and their controls were fed a high-fat diet (HFD) for 22 weeks. Glucose tolerance, urinary albumin-to-creatinine ratio, renal histology, and pro-inflammatory and pro-fibrotic markers were evaluated. Results showed that wild-type mice fed an HFD became obese with glucose intolerance and renal histological alterations mimicking a pre-diabetic condition; consequently, greater glomerular size and mesangial expansion were observed. Adam17 tubular deletion improved glucose tolerance and protected animals against glomerular injury and prevented podocyte loss in HFD mice. In addition, HFD mice showed more glomerular macrophages and collagen accumulation, which was prevented by Adam17 deletion. Galectin-3 expression increased in the proximal tubules and glomeruli of HFD mice and ameliorated with Adam17 deletion. In conclusion, Adam17 in proximal tubules influences glucose tolerance and participates in the kidney injury in an obese pre-diabetic murine model. The role of ADAM17 in the tubule impacts on glomerular inflammation and fibrosis.  相似文献   
762.
Two types of blends containing polyamide 6 and poly(propylene oxide) (PPO) were prepared. One of them was mixed with polycarbonate (PC) in a Brabender mixer. The other one was prepared in solution with the block copolymer as the interfacial agent. The blends were analyzed by 13C nuclear magnetic resonance techniques at solid state, such as: magic angle spinning (MAS); cross-polarization MAS, and variable contact time experiment. It was observed that the addition of PC in the nylon 6/PPO system causes a hardening of it, which can be attributed to strong links, like a hydrogen bond. The ideal quantity of block copolymer added to a blend to improve the compatibility is between 5 and 10%. An increase of the quantity of this agent probably makes it act as a third component. Therefore, both PC and block copolymer can be used as an interfacial agent for nylon 6/PPO blends in an ideal composition. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1635–1640, 1997  相似文献   
763.
Phase behavior of aqueous systems containing block copolymers of poly(ethylene oxide (PEO) and poly(propylene oxide) (PPO) was evaluated by building up temperature-concentration phase diagrams. We have studied bifunctional triblock copolymers (HO-PEO-PPO-PEO-OH) and monofunctional diblock copolymers (R-PEO-PPO-OH and R-PPO-PEO-OH, where R length is linear C4 and C12–14). The cloud points of the polymer solutions depended on EO/PO ratio, polarity, R length and position of the hydrophilic and hydrophobic segments along the molecule. Such factors influence on the solutions behavior was also analyzed in terms of critical micelle concentration (CMC), which was obtained from surface tension vs. concentration plots. Salts (NaCl and KCl) added into the polymer solutions change the solvent polarity decreasing the cloud points. On the other hand, the cloud points of the polymer solutions increased as a hydrotrope (sodium p-toluenesulfonate) was added. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1767–1772, 1997  相似文献   
764.
Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease all over the world due to the obesity pandemic; currently, therapeutic options for NAFLD are scarce, except for diet recommendations and physical activity. NAFLD is characterized by excessive accumulation of fat deposits (>5%) in the liver with subsequent inflammation and fibrosis. Studies in the literature show that insulin resistance (IR) may be considered as the key mechanism in the onset and progression of NAFLD. Recently, using natural products as an alternative approach in the treatment of NAFLD has drawn growing attention among physicians. In this review, the authors present the most recent randomized controlled trials (RCTs) and lines of evidence from animal models about the efficacy of nutraceutics in alleviating NAFLD. Among the most studied substances in the literature, the following molecules were chosen because of their presence in the literature of both clinical and preclinical studies: spirulina, oleuropein, garlic, berberine, resveratrol, curcumin, ginseng, glycyrrhizin, coffee, cocoa powder, epigallocatechin-3-gallate, and bromelain.  相似文献   
765.
This paper presents an original theoretical framework to model steel material properties in continuous casting line process. Specific properties arising from non-Newtonian dynamics are herein used to indicate the natural convergence of distributed parameter systems to fractional order transfer function models. Data driven identification from a real continuous casting line is used to identify model of the electromagnetic actuator device to control flow velocity of liquid steel. To ensure product specifications, a fractional order control is designed and validated on the system. A projection of the closed loop performance onto the quality assessment at end production line is also given in this paper.   相似文献   
766.

Scope

Obesity and insulin resistance (IR) are associated with epigenetic changes of gene expression. However, the relationship between micronutrients, epigenetic regulation of gene expression, and IR during development of diet-induced obesity has yet to be defined. Our objective is to describe the effect of micronutrient addition to diets on IR and its related genes during obesity development.

Methods and results

Male C57BL/6J mice are fed a high-fat (HFD) or low-fat (LFD) diets with or without a multi-vitamin mineral mix (MVM) addition containing vitamins A, B1, B6, B12, and Zn, and Se for 9 weeks. Compared to LFD mice, HFD mice have higher body weight, IR, fasting glucose, insulin, C-peptide, leptin, and hepatic triglyceride concentrations, and dysregulated gene expression in liver, muscle, pancreas, and fat tissues (p < 0.05). The addition of MVM reduces these HFD-induced effects. HFD downregulates 27 genes associated with insulin regulation and adipose tissue function across all tissues by an average of 47% and upregulates five genes by 230% (p < 0.001). Adding MVM downregulates five genes and upregulates one in HFD-fed mice. Both HFD and MVM alter one-carbon metabolites.

Conclusion

Addition of micronutrients to the HFD decreases IR and modifies associated gene expression in obese and lean mice.  相似文献   
767.
Corn grains with different filling times were fractionated in order to obtain their α 1,4 — α 1,6 glucopolysaccharide composition and structure. Sugary, waxy, flint and several hybrids were the varieties analyzed. There is an increase in the total content of polysaccharides, as the grain is completed. But, no differences in composition and structure were detected between the first sample analyzed (15th day after pollination) and the last one, which corresponds to the complete grain filling period. The methodology developed by us, allowed us to observe that the introduction of su character on the hybrids (F x S and S x F) has influence on the final polysaccharide structure. Also, in the F x W hybridα 1,4 — α 1,6 glucans, their structural characteristics were different from those of F or W pure.  相似文献   
768.
769.
Champagne cork popping out of standard 75 cL bottles was examined through high-speed infrared imaging for three various champagne temperatures (namely, 4, 12, and 18 °C). The cloud of gaseous CO2 gushing out of the bottleneck while cork popping (invisible in the visible light spectrum) was visualized. Both the volume of gaseous CO2 gushing out of the bottleneck, and its overall dynamic behavior were found to depend on the champagne temperature. The velocity of the cork popping out of the bottleneck was also measured, and found to logically increase with the champagne temperature. By considering that gases under pressure in the bottleneck experience adiabatic expansion while cork popping, a thermodynamic model was built that accounts for the major physical parameters that influence the volume of gaseous CO2 gushing out of the bottleneck, its drop of temperature, and its total energy released while cork popping. Only a small fraction of the total energy released while cork popping was found to be converted into the form of cork’s kinetic energy (only about 5%), whatever the champagne temperature.  相似文献   
770.
The present study was conducted in order to evaluate the starch components contained in several maize mutants. The α1,4-α1,6 glucopolysaccharides were fractionated according to their branching degree. The determination of the wavelenght of maximum absorption (γ max) in the presence of Krisman's reagent [12] as well as the glucose α1,6 linkages involved in the branching point were determined. The mutants analyzed possess characteristics that allow us to identify them according to the composition and structural properties of their polysaccharides (phytoglycogen, amylopectin, amylose).  相似文献   
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