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21.
Tanja Goyarts Klaus-Peter Brüssow Hana Valenta Ute Tiemann Kathrin Jäger Sven Dänicke 《Mycotoxin Research》2010,26(2):119-131
Six pregnant sows of 180.6 ± 5.6 kg were fed either a Fusarium-contaminated (4.42 mg DON and 48.3 μg ZON per kg, DON per os, n = 3) or a control diet (0.15 mg DON and 5 μg ZON/kg) in the period of days 63 and 70 of gestation. On day 63 of gestation, sows fed the control diet were implanted with an intraperitoneal osmotic minipump (delivery rate of 10 μL/h, for 7 days) containing 50 mg pure (98%) DON in 2 ml 50% DMSO (DON ip, n = 3). Frequent plasma samples were taken to estimate the kinetics after oral and ip DON exposure. The intended continuous delivery of DON by the intraperitoneal minipump could not be shown, as there was a plasma peak (Cmax) of 4.2–6.4 ng DON/mL either immediately (sow IP-2+3) or 2.5 h (sow IP-1) after implantation of the pump followed by a one-exponential decline with a mean half-time (t1/2) of 1.75–4.0 h and only negligible DON plasma concentrations after 12 h. Therefore, the DON ip exposure has to be regarded as one single dose 1 week before termination of experiment. The DON per os sows showed a mean basis level (after achieving a steady state) of DON plasma concentration of about 6–8 ng/mL, as also indicated by the plasma DON concentration at the termination of the experiment. On day 70, caesarean section was carried out, the fetuses were killed immediately after birth, and samples of plasma, urine, and bile were taken to analyze the concentration of DON and its metabolite de-epoxy-DON. At necropsy there were no macroscopic lesions observed in any organ of either sows or piglets. Histopathological evaluation of sows liver and spleen revealed no alterations. The proliferation rate of peripheral blood mononuclear cells (PBMC) with or without stimulation was not affected by the kind of DON treatment. The exposure of pregnant sows at mid-gestation (days 63–70, period of organogenesis) to a Fusarium toxin-contaminated diet (4.42 mg DON and 0.048 mg ZON per kg) or pure DON via intraperitoneal osmotic minipump did not cause adverse effects on health, fertility, maintenance of pregnancy, and performance of sows and their fetuses. However, DON was detected in fetus plasma, indicating that this toxin can pass the placental barrier and may cause changes in the proportion of white blood cells (lower monocyte and neutrophil and higher lymphocyte proportion in DON per os fetuses). 相似文献
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Ahmed AA Mohamed Ael-H Tzakou O Petropoulou A Hassan ME El-Maghraby MA Zeller KP 《Phytochemistry》2003,62(8):1191-1194
The aerial parts of Inula verbascifolia afforded two new xanthanes and a new germacranolide derivative, together with the known compounds inusoniolide, 4-O-dihydroinusoniolide and 9beta-hydroxyparthenolide. The structures were determined by spectral methods (IR, HRMS,1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC). 相似文献
25.
Pilot study of elevated levels of insulin-like growth factor-binding protein-2 as indicators of hepatocellular carcinoma 总被引:3,自引:0,他引:3
Ranke MB Maier KP Schweizer R Stadler B Schleicher S Elmlinger MW Flehmig B 《Hormone research》2003,60(4):174-180
BACKGROUND/AIMS: Insulin-like growth factor-binding protein-2 (IGFBP-2) is expressed in many malignant tissues, and elevated serum levels can be indicators of tumour activity in addition to conventional tumour markers. Our aim was to evaluate the role of IGFBP-2 levels together with insulin-like growth factor (IGF)-I, IGF-II and IGFBP-3 in the diagnostic work-up of patients with hepatocellular carcinoma (HCC). METHODS: In 50 (39 males, 11 females) histologically confirmed and TNM-graded patients with HCC who had not received adjuvant chemotherapy, the basal serum levels of IGF-I, IGF-II, IGFBP-3, IGFBP-2 and alpha-fetoprotein (AFP) were measured. The median age of the patients was 66 (37-84) years, body mass index was normal (25 (35-16) kg/m2). RESULTS: The levels of IGF-I, IGF-II and IGFBP-3 were diminished, as is the case when nutrition, hepatic function and growth hormone (GH) secretion are decreased. The levels of AFP and IGFBP-2 were markedly high. In 37 cases, IGFBP-2 levels were above the age-related norm, and in 40 cases AFP levels were also elevated. In 3 cases, both AFP and IGFBP-3 were normal, and in 4 cases AFP was high but IGFBP-2 normal, whereas in 10 cases AFP was normal but IGFBP-2 was high. CONCLUSIONS: In addition to AFP, IGFBP-2 appears to be a suitable marker for the evaluation of the serological status of HCC patients. A longitudinal study during disease management is required to assess the full potential of IGFBP-2 measurements as a marker. 相似文献
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C-phycocyanin and allophycocyanin from the red alga Rhodella violacea were investigated by electron microscopy and biochemical methods using samples taken from the same fractions.The molecular weights of the native biliprotein aggregates C-phycocyanin and allophycocyanin are about 139,000 (140,000) and 130,000 (145,000) as revealed by calibrated gel chromatography, gradient gel electrophoresis and morphological measurements on the basis of an average protein packing density. These molecular weights are direct evidence for a trimeric aggregation form ()3 of these biliproteins. Independently, their monomers were determined to be about 34,400 (C-phycocyanin) and 33,900 (allophycocyanin).C-phycocyanin and allophycocyanin are ringshaped, six-membered, biliprotein aggregates with dimensions of about 10.2×3.0 nm and 10.0×3.0 nm, respectively. The aggregates are made up of six subunits, 3 and 3, which are assumed to be associated in alternating positions. They are arranged in regular hexagons in C6 symmetry. Hexameric aggregates ()6, so far only isolated for C-phycocyanin, originate by face to face association of two trimeric aggregates. 相似文献
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Weiland R Macht M Ellgring H Gross-Lesch S Lesch KP Pauli P 《Attention deficit and hyperactivity disorders》2011,3(1):53-60
Recently, research on olfactory functions in attention-deficit/hyperactivity disorder (ADHD) has become prominent, whereas gustation has never been investigated. Increased odor sensitivity was found in medication-na?ve children with ADHD, but not in adult ADHD, which might be due to a dopaminergic dysregulation presumed to underlie this disorder. Taste sensitivity, in particular bitter sensitivity as a hereditary trait, also might be altered in ADHD. To examine olfactory and gustatory functions in adult ADHD patients, we assessed odor sensitivity by Sniffin' Sticks, taste sensitivity by taste strips, and bitter sensitivity by the one-solution test in women with ADHD (n = 12), Bulimia Nervosa (n = 12), and healthy control women (n = 12). Bulimia Nervosa as second patient group was included to control for effects of impulsivity. Preliminary results indicate that ADHD patients were significantly more often classified as tasters, i.e. perceived the bitter taste as more intense, compared to both bulimic patients and healthy controls. No group differences were found with regard to general odor and taste sensitivity. It is proposed that the higher frequency of tasters in ADHD patients might underlie a genetic variation of the bitter receptor-dependent signaling pathway associated with ADHD. 相似文献
28.
Thrombin activates AMP-activated protein kinase in endothelial cells via a pathway involving Ca2+/calmodulin-dependent protein kinase kinase beta 下载免费PDF全文
AMP-activated protein kinase (AMPK) is a sensor of cellular energy state in response to metabolic stress and other regulatory signals. AMPK is controlled by upstream kinases which have recently been identified as LKB1 or Ca2+/calmodulin-dependent protein kinase kinase beta (CaMKKbeta). Our study of human endothelial cells shows that AMPK is activated by thrombin through a Ca2+-dependent mechanism involving the thrombin receptor protease-activated receptor 1 and Gq-protein-mediated phospholipase C activation. Inhibition of CaMKK with STO-609 or downregulation of CaMKKbeta using RNA interference decreased thrombin-induced AMPK activation significantly, indicating that CaMKKbeta was the responsible AMPK kinase. In contrast, downregulation of LKB1 did not affect thrombin-induced AMPK activation but abolished phosphorylation of AMPK with 5-aminoimidazole-4-carboxamide ribonucleoside. Thrombin stimulation led to phosphorylation of acetyl coenzyme A carboxylase (ACC) and endothelial nitric oxide synthase (eNOS), two downstream targets of AMPK. Inhibition or downregulation of CaMKKbeta or AMPK abolished phosphorylation of ACC in response to thrombin but had no effect on eNOS phosphorylation, indicating that thrombin-stimulated phosphorylation of eNOS is not mediated by AMPK. Our results underline the role of Ca2+ as a regulator of AMPK activation in response to a physiologic stimulation. We also demonstrate that endothelial cells possess two pathways to activate AMPK, one Ca2+/CaMKKbeta dependent and one AMP/LKB1 dependent. 相似文献
29.
Ectopic expression of an amino acid transporter (VfAAP1) in seeds of Vicia narbonensis and pea increases storage proteins 下载免费PDF全文
Rolletschek H Hosein F Miranda M Heim U Götz KP Schlereth A Borisjuk L Saalbach I Wobus U Weber H 《Plant physiology》2005,137(4):1236-1249
Storage protein synthesis is dependent on available nitrogen in the seed, which may be controlled by amino acid import via specific transporters. To analyze their rate-limiting role for seed protein synthesis, a Vicia faba amino acid permease, VfAAP1, has been ectopically expressed in pea (Pisum sativum) and Vicia narbonensis seeds under the control of the legumin B4 promoter. In mature seeds, starch is unchanged but total nitrogen is 10% to 25% higher, which affects mainly globulin, vicilin, and legumin, rather than albumin synthesis. Transgenic seeds in vitro take up more [14C]-glutamine, indicating increased sink strength for amino acids. In addition, more [14C] is partitioned into proteins. Levels of total free amino acids in growing seeds are unchanged but with a shift toward higher relative abundance of asparagine, aspartate, glutamine, and glutamate. Hexoses are decreased, whereas metabolites of glycolysis and the tricarboxylic acid cycle are unchanged or slightly lower. Phosphoenolpyruvate carboxylase activity and the phosphoenolpyruvate carboxylase-to-pyruvate kinase ratios are higher in seeds of one and three lines, indicating increased anaplerotic fluxes. Increases of individual seed size by 20% to 30% and of vegetative biomass indicate growth responses probably due to improved nitrogen status. However, seed yield per plant was not altered. Root application of [15N] ammonia results in significantly higher label in transgenic seeds, as well as in stems and pods, and indicates stimulation of nitrogen root uptake. In summary, VfAAP1 expression increases seed sink strength for nitrogen, improves plant nitrogen status, and leads to higher seed protein. We conclude that seed protein synthesis is nitrogen limited and that seed uptake activity for nitrogen is rate limiting for storage protein synthesis. 相似文献
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