Heterogeneity of tachykinin receptors in the rabbit lung

The tachykinins, substance P (SP) and neurokinin A (NKA), are agonists for the NK(1) and NK(2) receptors, respectively. Tachykinins have various respiratory effects, including bronchoconstriction. This study characterizes tachykinin binding sites in the rabbit lung. We hypothesize that (2-[(125)I]iodohistidyl(1))Neurokinin A ([(125)I]NKA) interacts with NK1 and NK2 binding sites in the rabbit lung. The K d determined from saturation isotherms was 0.69 times/divided by 1.14 nM (geometric mean times/divided by SEM) and the B max was 4.15 + or - 0.22 femtomole/mg protein (arithmetic mean + or - SEM). Competitive inhibition studies with NKA, SP and various selective tachykinin agonists showed the rank order of potency; [beta-Ala(8)]-Neurokinin A 4-10 = SP > NKA > [Sar(9),Met(02)11]-Substance P. [beta-Ala(8)]-Neurokinin A 4-10, a selective NK(2) agonist, and SP inhibition of [(125)I]NKA binding were best described using a two-site model. Competitive inhibition studies using the selective nonpeptide NK(2) antagonist (SR 48968) and the selective nonpeptide NK(1) antagonist (CP 96,345) revealed Ki's of 5.5 nM and 8.1 nM, respectively. Our data therefore suggest that [(125)I]NKA binds to both the NK(1) and NK(2) receptors in the lung.     

Insulin-induced activation of NADPH-dependent H2O2 generation in human adipocyte plasma membranes is mediated by Galphai2

Human fat cells possess a multireceptor-linked H2O2-generating system that is activated by insulin. Previous studies revealed that manganese was the sole cofactor required for a hormonal regulation of NADPH-dependent H2O2 generation in vitro. In this report it is shown that the synergistic activation of NADPH-dependent H2O2 generation by Mn2+ and insulin was blocked by GDPbetaS (guanosine 5'-O-(2-thiodiphosphate)), pertussis toxin and COOH-terminal anti-Galphai1-2 or the corresponding peptide. Consistently, manganese could be replaced by micromolar concentrations of GTPgammaS (guanosine 5'-O-(3-thiotriphosphate)), which increased NADPH-dependent H2O2 generation by 20-40%. Insulin shifted the dose response curve for GTPgammaS to the left (>10-fold) and increased the maximal response. In the presence of 10 microM GTPgammaS, the hormone was active at picomolar concentrations, indicating that insulin acted via its cognate receptor. The insulin receptor and Gi were co-adsorbed on anti-Galphai and anti-insulin receptor beta-subunit (anti-IRbeta) affinity columns. Partially purified insulin receptor preparations contained Galphas, Galphai2, and Gbetagamma (but no Galphai1 or Galphai3). The functional nature of the insulin receptor-Gi2 complex was made evident by insulin's ability to modulate labeling of Gi by bacterial toxins. Insulin action was mimicked by activated Galphai, but not by Galphao or Gbetagamma, indicating that insulin's signal was transduced via Galphai2. Thus, NADPH oxidase is the first example of an effector system that is coupled to the insulin receptor via a heterotrimeric G protein.     

A Probable Flavoring Principle in Vegetable-Protein Hydrolysates

SUMMARY— The characteristic seasoning flavor of hydrolyzed vegetable proteins has previously been attributed to α-ketobutyric acid formed from threonine under the conditions of acid-hydrolysis. However, pure α-ketobutyric acid is virtually odorless and tasteless, and it develops the characteristic flavor only upon ageing. The true flavoring principle is probably α-hydroxy-β-methyl-Δ.^α,β-γ-hexenolactone, which is formed from the acid by dimerization, lactonization, and decarboxylation. This conversion occurs spontaneously, but is greatly accelerated under acidic conditions.     

Electronic and Human Nose in the Detection of Aroma Differences Between Strawberry Ice Cream of Varying Fat Content

ABSTRACT: The capability of an electronic nose, MGD-1, in the detection of aroma differences among 5 samples of strawberry ice cream of varying fat content (0,9, or 18% dairy or vegetable fat) was compared with the human nose. R-indices were determined to detect sensory differences. In addition, the headspace compositions of samples were determined with static headspace gas chromatography. The effect of the amount of fat on the aroma release could be detected with all three methods. The headspace of the nonfat sample was very different from the other samples, but samples containing 9 or 18% of fat were also differentiated. The type of fat did not significantly affect the aroma release. The MGD- 1's capability for detecting the aroma differences was fairly comparable with the sensory and the static headspace gas chromatographic method.     

Removal of soft deposits from the distribution system improves the drinking water quality

Deterioration in drinking water quality in distribution networks represents a problem in drinking water distribution. These can be an increase in microbial numbers, an elevated concentration of iron or increased turbidity, all of which affect taste, odor and color in the drinking water. We studied if pipe cleaning would improve the drinking water quality in pipelines. Cleaning was arranged by flushing the pipes with compressed air and water. The numbers of bacteria and the concentrations of iron and turbidity in drinking water were highest at 9 p.m., when the water consumption was highest. Soft deposits inside the pipeline were occasionally released to bulk water, increasing the concentrations of iron, bacteria, microbially available organic carbon and phosphorus in drinking water. The cleaning of the pipeline decreased the diurnal variation in drinking water quality. With respect to iron, only short-term positive effects were obtained. However, removing of the nutrient-rich soft deposits did decrease the microbial growth in the distribution system during summer when there were favorable warm temperatures for microbial growth. No Norwalk-like viruses or coliform bacteria were detected in the soft deposits, in contrast to the high numbers of heterotrophic bacteria.     

中心组合设计优化绿茶色素提取研究

目的:以杭州低档绿茶碎末为原料,提取绿茶色素.方法:研究微粉碎和酶对绿茶色素的浸提效果,并用中心组合设计浸提工艺.结果:绿茶经粉碎过80目筛后采用双酶法提取,先加入果胶酶再加入纤维素酶的绿茶色素的浸提率最佳,最优浸提工艺条件为乙醇浓度82%,反应时间49 min,醇茶比12:1,反应温度79℃,绿茶色素浸提卒为48.69%,以叶绿素计为1.941 mg/g.结论:用中心组合实验设计求得绿茶色素浸提率的数学模型是可行的,并且以杭州低档绿茶碎末提取绿茶色素可以提高茶叶附加值.     

Evaluation of surface contamination and the presence of Listeria monocytogenes in fish processing factories

The main objective of this study was to determine the level of surface contamination in fish processing factories and the presence of Listeria in the factory environment and products. Another objective was evaluation of the different hygiene-monitoring methods. Total aerobic heterotrophic and enterobacteria, yeast and mold samples were collected and ATP levels measured in 28 factories. The number of well or adequately washed and disinfected factories was small (2 of 28), in terms of total aerobic heterotrophic bacterial counts on the surfaces. Most surfaces contaminated with bacteria were heavily contaminated. Results of the ATP and the total bacteria contact agar slide methods were poorly correlated (r = 0.21) although 68% of the samples were categorized as good to moderate or unacceptable with both methods. The Listeria-positive surface samples usually contained increased numbers of total bacteria (70.9%). The contamination of products and raw fish together with Listeria spp. was 45% and with Listeria monocytogenes 12%. Cold smoked fish was the most contaminated, with 75% Listeria spp. and cold salted fish with 20% L. monocytogenes. Listeria innocua was found in the samples more than twice as often as L. monocytogenes.     

Benefits of Partitioning in a Projection-based and Realizable Model-order Reduction Flow

Model-order reduction (MOR) is a typical approach to speed up the post-layout verification simulation step in circuit design. This paper studies the benefits of using circuit partitioning in a complete MOR flow. First, an efficient reduction algorithm package comprising of partitioning, reduction, and realization parts is presented. The reduction flow is then discussed using theoretical analysis and simulations from an array of 65-nm technology node interconnect circuits. It is shown that the reduction efficiency and computational costs quickly worsen with increased circuit size when using a direct projection-based MOR approach. In contrast, by using partitioning, the MOR can retain the scalability of the reduction problem, being computationally lighter and more efficient even with larger circuits. In addition, using partitioning may improve the robustness of the MOR flow in cases with circuits with many ports or sensitive verification simulations.