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881.
Light color and savory flavor enhancer are attractive for consumers and food producers. The effect of addition time of l ‐cysteine on inhibiting color formation was investigated in soybean peptide‐xylose system, and the possible pathway was explored. Once dicarbonyl compounds were formed during the Maillard reaction, the addition of l ‐cysteine had no color‐inhibiting effect; if l ‐cysteine was added immediately after the Amadori compound was formed, the extraordinary color‐inhibiting effect was observed. Therefore, an improved way to inhibit color formation was proposed on the basis of the interaction of l ‐cysteine and Amadori compounds by controlling the addition time of l ‐cysteine through gradient temperature‐elevating Maillard reaction. The system was heated at 80 °C for 60 min to form Amadori compounds, followed by the addition of L‐cysteine, and the temperature was raised to 120 °C and held for 110 min. Compared with traditional products, the lightest color product was found desirable by GC/MS analysis and sensory evaluation. The novel method proposed can be a guide for the industrial preparation of light‐colored products. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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Mature connective tissue mast cells (CTMC) have not been previously available as a cell line from any species. Here we describe 15 novel mast cell lines (KiSV-MC) that were derived by coculturing murine splenocytes with fibroblasts that produce a Ki-ras-containing murine sarcoma virus. Some of the KiSV-MC lines are similar to CTMC in that they synthesize predominantly heparin proteoglycans, and contain up to 35 micrograms of histamine and 2.2 units of carboxypeptidase A/10(6) cells in secretory granules which stain red with Safranin. Other cell lines display phenotypic characteristics intermediate to CTMC and mucosal-like mast cells in being predominantly Safranin-, having lower amounts of histamine and carboxypeptidase A, and in synthesizing chondroitin sulfate E proteoglycans in preference to heparin proteoglycans. When the individual KiSV-MC lines were compared, a linear relationship was found between the number of Safranin+ granules, the cellular contents of histamine and carboxypeptidase A, and the biosynthesis of heparin relative to chondroitin sulfate E proteoglycans. Upon sensitization with monoclonal IgE and exposure to hapten-specific antigen, the cells exocytose the contents of their secretory granules. Thus, these immortalized cells provide the first source of CTMC-like lines for chemical and functional analysis and illustrate that murine mast cells can express a continuum of phenotypes.  相似文献   
884.
Acinar cells in acute pancreatitis (AP) die through apoptosis and necrosis, the impacts of which are quite different. Early clinical interference strategies on preventing the progress of AP to severe acute pancreatitis (SAP) are the elimination of inflammation response and inhibition of necrosis. Muscarinic acetylcholine receptor M3 was encoded by Chrm3 gene. It is one of the best-characterized receptors of pancreatic β cells and regulates insulin secretion, but its function in AP remains unclear. In this study, we explored the function of Chrm3 gene in the regulation of cell death in l -arginine-induced SAP animal models. We found that Chrm3 was upregulated in pancreatitis, and we further confirmed the localization of Chrm3 resided in both pancreatic islets and acinar cell membranes. The reduction of Chrm3 decreased the pathological lesion of SAP and reduced amylase activities in serum. Consistently, Chrm3 can suppress acinar cells necrosis markedly, but has no effect on regulating apoptosis after l -arginine treatment. It was shown that Chrm3 attenuated acinar cells necrosis at least in part by stabilizing caspase-8. Thus, this study indicates that Chrm3 is critical participants in SAP, and regulation of Chrm3 expression might be a useful therapeutic strategy for preventing pathologic necrosis.  相似文献   
885.
Twenty-five isolates of F. acuminatum, 38 of F. avenaceum, 1 of F. culmorum, 31 of F. oxysporum and 56 of F. sambucinum were obtained in 1983, 1984 and 1986 from cereal grains and soil from various parts of Norway. The isolates were grown on an autoclaved Uncle Ben's parboiled rice medium and examined for production of trichothecenes and other toxins and for toxicity in rat feeding tests. F. culmorum N46C(2) and Fusarium sambucinum 45-86-A produced zearalenone (F-2) 864 and 665 ppm, respectively and caused uterine enlargement in rats. Most of these isolates produced no known trichothecene mycotoxins that could account for the toxicity that was demonstrated in the rat feeding tests. All but F. avenaceum N26B produced fusarin C (1.5 ppm) but caused no toxic effects in rat feeding test. None of the isolates produced fusarochromanone (TDP-1). Thirteen isolates of F. acuminatum, 16 of F. avenaceum, 14 of F. oxysporum and 3 of F. sambucinum produced a cytotoxic factor which we named HM-8. One isolate of F. avenaceum, 12 of F. oxysporum and 46 of F. sambucinum produced a hemorrhagic factor which we named H-1 (wortmannin). Twenty isolates of F. acuminatum, 22 of F. avenaceum, 17 of F. oxysporum and 1 of F. sambucinum produced moniliformin. Four isolates of F. acuminatum, 9 of F. avenaceum, 25 of F. oxysporum and 52 of F. sambucinum caused death to rats. Three isolates of F. avenaceum, 19 of F. oxysporum and 47 of F. sambucinum induced hemorrhage in various organs. All isolates caused decreased weight gain, relative to the control diets.  相似文献   
886.
The association between metabolic syndrome (MS) and bone health remains unclear. We aimed to study the association between MS and hip bone geometry (HBG), femoral neck bone mineral density (FN-BMD), and the risk of osteoporosis and incident fractures. Data of 2040 women and 1510 men participants in the third visit (1997–1999) of the Rotterdam Study (RSI-3), a prospective population based cohort, were available (mean follow-up 6.7 years). MS was defined according to the recent harmonized definition. HBG parameters were measured at the third round visit whereas FN-BMD was assessed at the third round and 5 years later. Incident fractures were identified from medical registry data. After correcting for age, body mass index (BMI), lifestyle factors and medication use, individuals with MS had lower bone width (β = -0.054, P = 0.003), lower cortical buckling ratio (β = -0.81, P = 0.003) and lower odds of having osteoporosis (odds ratio =0.56, P = 0.007) in women but not in men. Similarly, MS was associated with higher FN-BMD only in women (β = 0.028, P=0.001). In the analyses of MS components, the glucose component (unrelated to diabetes status) was positively associated with FN-BMD in both genders (β = 0.016, P = 0.01 for women and β = 0.022, P = 0.004 for men). In men, waist circumference was inversely associated with FN-BMD (β = -0.03, P = 0.004). No association was observed with fracture risk in either sex. In conclusion, women with MS had higher FN-BMD independent of BMI. The glucose component of MS was associated with high FN-BMD in both genders, highlighting the need to preserve glycemic control to prevent skeletal complications.  相似文献   
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Despite the unique advantages of the metal‐organic framework of Prussian blue analogues (PBAs), including a favorable crystallographic structure and facile diffusion kinetics, the capacity of PBAs delivered in aqueous systems has been limited to ≈60 mA h g?1 because only single species of transition metal ions incorporated into the PBAs are electrochemically activated. Herein, vanadium hexacyanoferrate (V/Fe PBA) is proposed as a breakthrough to this limitation, and its electrochemical performance as a cathode for aqueous rechargeable batteries (ARBs) is investigated for the first time. V/Fe PBAs are synthesized by a simple co‐precipitation method with optimization of the acidity and molar ratios of precursor solutions. The V/Fe PBAs provide an improved capacity of 91 mA h?1 under a current density of 110 mA g?1 (C‐rate of ≈1.2 C), taking advantage of the multiple‐electron redox reactions of V and Fe ions. Under an extremely fast charge/discharge rate of 3520 mA g?1, the V/Fe PBA exhibits a sufficiently high discharge capacity of 54 mA h g?1 due to its opened structure and 3D hydrogen bonding networks. V/Fe PBA‐based ARBs are the most promising candidates for large‐scale stationary energy storage systems due to their high electrochemical performance, reasonable cost, and high efficiency.  相似文献   
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