Objectives This study assessed dietary habits and exposure to selenium, persistent organochlorine compounds, methylmercury, and methylamines among Swedish fishermen. Methods Two hundred and fifty ...randomly selected subjects from a cohort of 2896 fishermen from the Swedish east coast (Baltic Sea) and 8477 fishermen from the west coast (Skagerrak and Kattegatt) were interviewed along with 250 referents. Subgroups of fishermen and referents from different coastal areas were also selected for blood and urine sampling. Results The interview data showed that fishermen ate almost twice as much fish as the 250 referents from the general population. The blood levels of mercury were twice as high, and the plasma selenium levels were 10—15% higher in the fishermen than in the referents. There was, however, no difference between the fishermen's cohorts with respect to these variables. Fishermen from the east coast ate more fatty fish than fishermen from the west coast, and they also had higher blood levels of persistent organochlorine compounds such as polychlorinated biphenyls and poly chlorinated dibenzo p-dioxins and furans (present in fatty fish species in the Baltic Sea) than both the westcoast fishermen and the referents. Conclusions A cohort of Swedish eastcoast fishermen might be a suitable study base for epidemiologie studies on the mortality and cancer morbidity associated with dietary exposure to persistent organochlorine compounds.
Human thyrocytes were found to synthesize and secrete the selenoenzyme extracellular glutathione peroxidase (E-GPX), a process which was controlled by the Ca2+/phosphoinositol second-messenger ...cascade. The potential involvement of thyroidal E-GPX in the regulation of thyroid-hormone synthesis and in the protection of the thyrocyte from peroxidative damage is discussed.
Four cultivars of strawberries (Senga Sengana, BFr77111, Elsanta, and Honeoye) were studied for their content of antioxidants, total antioxidant capacity, and low molecular weight carbohydrates in ...relation to harvest year, ripening stage, and cold storage. For ascorbic acid, chlorogenic acid, ellagic acid, and total antioxidative capacity, measured in both water-soluble and water-insoluble extracts, there was a 2−5-fold variation among cultivars. Unripe berries contained lower concentrations of chlorogenic acid and p-coumaric acid and also quercetin and kaempferol compared with riper berries. During cold storage for up to 3 days, relatively few changes in the concentration of the different antioxidants occurred. The concentrations of several investigated parameters were interrelated, for example, for ascorbic acid and water-soluble antioxidant capacity and for ellagic acid and water-insoluble antioxidant capacity. The dominating sugars in strawberries were fructose and glucose, but considerable amounts of sucrose were also present, and their contents varied among cultivars, giving a predicted glycemic index of ∼81. Verbascose, raffinose, and stachyose were found in only minor amounts. The study shows that the concentration of a number of bioactive compounds in strawberries varied according to cultivar, ripening stage, and storage. This information should make it possible to select strawberries with an optimal content of bioactive compounds. Keywords: Flavonol; ascorbate; dehydroascorbate; phenolic acids; hydroxycinnamic acids; ellagic acid; chlorogenic acid; sucrose; fructose; glucose; oligosaccharides; ABTS method; strawberry; Fragaria × ananassa
Thirty-five varieties of the green pea (
Pisum sativum L.) were analysed for their total antioxidant capacity (TAC). After blanching and freezing, the water-soluble fraction had, on average, a TAC of ...0.61(0.22) μmol/g (mean(SD)) and the water-insoluble fraction a value of 0.23(0.08) μmol/g. There was a significant correlation between the TAC in the water-soluble and water-insoluble fractions (
r=0.41;
p<0.001
). The peas had been grown during two consecutive years and were harvested at two different periods during the second year, 1999. Regarding the antioxidant capacity in both the water-soluble and the water-insoluble extract, there was a significant difference between the varieties but not between the harvest periods. A significant correlation (
r=0.72) between TAC in the water-soluble fraction and ascorbic acid content was found. Ascorbic acid accounted for a large part of the water-soluble antioxidant capacity. Further studies are necessary to reveal other compounds explaining the variation in pea antioxidant capacity and the mechanisms involved. Measurement of TAC may be a convenient route for the selection of pea varieties with optimal functional and health effects.
Glutathione peroxidase activity (GSHPx), total and soluble selenium in two muscles from five species were compared (chicken, duck, turkey, ostrich and lamb). The highest GSHPx activity, found in duck ...muscles (4.8 U/g; 3.0 U/g), was significantly higher than that in lamb (1.8 U/g; 1.4 U/g), turkey (1.2 U/g; 0.6 U/g), chicken (1.0 U/g; 0.7 U/g), and ostrich muscles (0.9 U/g; 0.8 U/g). GSHPx activities were significantly higher in the oxidative muscles from chicken (thigh), duck (breast), turkey (thigh) and lamb (PM) than those in the corresponding glycolytic muscles (breast, thigh, breast and LD, respectively). Also the total selenium content was higher in duck muscles (149 ng/g; 139 ng/g), than in lamb (171 ng/g/PM, M. psoas major/ and 86 ng/g /LD, M. longissimus dorsil), chicken (117 ng/g; 109 ng/g), ostrich (106 ng/g; 103 ng/g) and turkey muscles (110 ng/g; 70 ng/g). The selenium content was significantly higher in the oxidative muscles of lamb and turkey than in the corresponding glycolytic muscles. The percentage of soluble selenium in lamb PM was lower (32%) than that in all other muscles' (range 48-76%). The study thus showed considerable variation, among species, of glutathione peroxidase activity, total and soluble selenium content in muscle, which may be important for the oxidative stability and nutritional value of different meat products. (C) 2003 Elsevier Ltd. All rights reserved.
Cyclic voltammetry (CV), rotating disk electrode (RDE) linear sweep voltammetry and flow-injection amperometry (FIAmp) were used to investigate the possibility to determine antioxidants in bovine ...milk, whey and low-molecular-weight (LMW) fractions of whey. Using CV one major current wave was found in all types of samples at oxidation potentials between +600 and +700
mV against Ag
|
AgCl|0.1
mol
l
−1 KCl. The wave registered for the LMW fraction disappeared after treatment with uricase as shown by CV and RDE, indicating that the major antioxidant in the LMW fraction may be urate. The antioxidant capacities of the LMW fractions were also measured by the FIAmp method using an oxidation potential of +700
mV with Trolox as standard, and values between 100 and 130
μmol
l
−1 Trolox equivalents were obtained. It is concluded that different electrochemical methods can be used to measure antioxidants in milk.
In colostrum collected 0–80
h postpartum the contents of immunoglobulins (Igs), transforming growth factor beta-2 (TGF-
β2), insulin-like growth factor-1 (IGF-1) and growth hormone (GH) were ...analysed. Colostrum initially contained 90
mg
mL
−1 IgG1, 2.8
mg
mL
−1 IgG2, 1.6
mg
mL
−1 IgA, 4.5
mg
mL
−1 IgM, and these concentrations declined by 92%, 87%, 93% and 84%, respectively, in the samples collected later. Of the growth factors, colostrum initially contained 289–310
ng
mL
−1 TGF-
β2 and the concentration diminished to 66
ng
mL
−1. The content of IGF-1 and GH postpartum decreased from 870 to 150
ng
mL
−1, and from 0.17 to <0.03
ng
mL
−1, respectively. Heat treatment and freeze-drying of colostral whey decreased the content of Igs to 75%, while the contents of IGF-1 and TGF-
β2 were unaffected. A similar processing, including filtration steps reduced also the IGF-1 and TGF-
β2 by 25%. IgM seems to be the most sensitive of the Igs to processing.
Glutathione peroxidase (GSHPx) activity, and total and soluble selenium content were compared in five bovine and porcine organs. The highest GSHPx activity in porcine tissues was found in the liver ...(35.0 U/g), spleen (29.3 U/g) and kidney (27.3 U/g) with much lower values in the heart (1.8 U/g) and diaphragm (0.8 U/g). A different pattern with lower inter-organ variation in GSHPx activity was observed in cattle: kidney (8.5 U/g), spleen (8.0 U/g), heart (5.8 U/g), liver (4.0 U/g) and diaphragm (2.1 U/g). The total selenium content was similar in both species with the highest content in the kidney (1764 and 1665 ng/g; pig/bovine), followed by liver (533 and 307 ng/g), spleen (370 and 284 ng/g), heart (201 and 205 ng/g) and diaphragm (144 and 116 ng/g). The percentage of soluble selenium varied more among the pig organs (46–94%) than among bovine organs (61–75%). The results show a marked variation in the activity of the selenium-containing GSHPx among organs and species in spite of a similar rank order of selenium content in the two species. Since GSHPx has a role in food stability and the intake of selenium is marginal in many European countries, the results add to the background information concerning the use of selenium rich organs as human foods.
Designing multi-processor systems-on-chips becomes increasingly complex, as more applications with realtime requirements execute in parallel. System resources, such as memories, are shared between ...applications to reduce cost, causing their timing behavior to become inter-dependent. Using conventional simulation-based verification, this requires all concurrently executing applications to be verified together, resulting in a rapidly increasing verification complexity. Predictable and composable systems have been proposed to address this problem. Predictable systems provide bounds on performance, enabling formal analysis to be used as an alternative to simulation. Composable systems isolate applications, enabling them to be verified independently. Predictable and composable systems are built from predictable and composable resources. This paper presents three general techniques to implement and model predictable and composable resources, and demonstrates their applicability in the context of a memory controller. The architecture of the memory controller is general and supports both SRAM and DDR2/DDR3 SDRAM and a wide range of arbiters, making it suitable for many predictable and composable systems. The modeling approach is based on a shared-resource abstraction that covers any combination of supported memory and arbiter and enables system-level performance analysis with a variety of well-known frameworks, such as network calculus or data-flow analysis.
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