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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Biotechnology letters 8 (1986), S. 219-223 
    ISSN: 1573-6776
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary Application of chemical additives to alter the rate of retting of desiccated flax stems was successful. Treatment with ethylenediaminetetra-acetic acid (EDTA) and urea increased the rate of retting. Increases, in the population of fungal colonisers were observed on urea-treated stems but not after EDTA treatment. Enhanced PG activities were detected in stems treated with EDTA and maimum PL and xylanase activities were detected in stems treated with urea. Urea treated stems produced relatively finer fibres compared to fibres from EDTA treated stems of controls.
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  • 2
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Graphite has been employed as a working electrode in the controlled potential coulometric determination of uranium and plutonium. The couples U(VI)/U(IV) and Pu(IV)/Pu(III) employed for analysis have diverse redox potentials and commonly the working electrodes employed are mercury and platinum. A graphite electrode in the shape of a beaker showed satisfactory performance for the quantitative reduction of U(VI) to U(IV) and Pu(IV) to Pu(III) and also for quantitative oxidation of Pu(III) to Pu(IV). Studies on the levels of the background current, blank values and their reproducible behaviour in acid media have been carried out with a view to achieve good precision and accuracy. A software-based predictive evaluation technique of end-point charge has been investigated. The results have shown that the graphite electrode can be used for the determination of both uranium and plutonium in the presence of each other with a precision and accuracy of better than ±0.5%.
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  • 3
    ISSN: 1573-4919
    Keywords: heme oxygenase ; ubiquitin ; myocardial stunning ; pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Heme oxygenase (HO) isozymes, HO-1 and HO-2 catalyze the cleavage of heme b to form the antioxidant biliverdin IXa, iron and the putative cellular messenger carbon monoxide (CO). Heat and stress have been reported to induce the expression of HO-1, in analogy to ubiquitin, a protein of 8 kDa involved in ATP dependent proteolysis. Earlier, we have shown in anesthetized pigs that brief periods of coronary artery occlusion followed by reperfusion produce prolonged regional cardiac dysfunction (stunning) associated with altered expression of a number of genes. In the present study, we report on a coordinated expression pattern of HO-1 and ubiquitin in the same porcine model in which the left anterior descending coronary artery (LAD) was occluded for 10 min and reperfused for 30 min (group I) and after a second occlusion of 10 min, reperfused for either 30 min (group II) or 90 min (group 111) or 210 min (group IV). Myocardial tissue from LAD (stunned) and left circumflex coronary artery (LCx, control) perfused regions were collected in liquid nitrogen and analysed by Northern and dot blot hybridization techniques. We demonstrated a basal myocardial expression of multiple mRNAs (monomer and polymers) encoding ubiquitin and a single mRNA species (1.8 kb) encoding HO-1. However, the expression of both genes was drastically enhanced in the stunned myocardium as compared to the control in groups II and III with maximum mRNAs levels in group II. These results suggest that the myocardial adaptive response to ischemia involves the coordinated induction of HO-1 and ubiquitin, which may be indicative for the existence of a pathophysiologically important defense mechanism whereby, both degradation of denatured cellular proteins and generation of biologically active products of heme metabolism are accelerated.
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  • 4
    ISSN: 1436-6215
    Keywords: Dietary protein ; Vitamin A ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Es wurde der Einfluß von Qualität und Quantität von Nahrungsproteinen auf die Verteilung einer einzigen massiven Dosis von Vitamin A in verschiedenen Organen wachsender Wistar-Ratten untersucht. Die Untersuchungen wurden mit Casein- und Bengal-Gram-Diäten mit 20 % und 10 % Proteingehalt und auch mit radioaktiv markiertem Retinylacetat durchgeführt. Die Ergebnisse zeigen, daß die Leberspeicherung sowohl von Vitamin A aus der Nahrung als auch die einer einzigen starken Vitamin-A-Gabe (20 000 I.U.) stark herabgesetzt war bei Ratten, die nach der Bengal-Gram-Diät gefüttert wurden, verglichen mit Ratten, die auf Casein-Diät gesetzt waren. Im Gegensatz zur Leberspeicherung ist das Vitamin-A-Niveau im Plasma in allen Gruppen vergleichbar. Füttern niedriger Protein-Qualität reduzierte die Gewebeverteilung von [3H]-Retinylacetat sowohl bei Kontrollratten als auch bei solchen, denen eine massive Dosis Vitamin A gegeben wurde. Diese Untersuchung läßt vermuten, daß sowohl schlechte Qualität als auch unzureichende Mengen von Nahrungsproteinen nachteilige Einflüsse auf den Vitamin-A-Zustand wachsender Ratten haben.
    Notes: Summary The influence of the quality and the quantity of dietary proteins on the distribution of a single massive dose of vitamin A in various organs of growing Wistar strain rats has been studied by using casein and bengal gram diets at 20 % and 10 % protein levels. The distribution of [3H]-retinyl acetate in various tissues was also investigated in these dietary conditions. The results show that the hepatic storage of dietary as well as a single massive dose (20,000 I.U.) of vitamin A was profoundly decreased in the rats fed on bengal gram diets as compared to those fed on casein diets. Regardless of hepatic stores, the plasma vitamin A levels were comparable in all the groups. Feeding of low quality of protein reduced the tissue distribution of [3H]-retinyl acetate in control as well as rats given a massive dose of vitamin A. This study suggests that both the poor quality and the inadequate quantity of dietary protein are detrimental influences on the vitamin A status of the growing rats.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 14 (1998), S. 83-85 
    ISSN: 1438-2199
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 6
    ISSN: 1438-2199
    Keywords: Keywords: Amino acids ; Nerve lesion ; Neuropathic pain ; Heme oxygenase ; Carbon monoxide ; Cell injury ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary. The influence of carbon monoxide (CO) on chronic spinal nerve lesion induced spinal cord neurodegeneration was examined using immunohistochemical expression of the constitutive isoform of its synthesising enzyme, hemeoxygenase-2 (HO-2) in a rat model. Spinal nerve lesion at L-5 and L-6 level was produced according to the Chung model of neuropathic pain and rats were allowed to survive for 8 weeks. Sham operated rats, in which the spinal nerves were exposed but not ligated, served as controls. Ligation of spinal nerves in rats resulted in an upregulation of HO-2 expression which was most pronounced in the ipsilateral gray matter of the spinal cord compared to the contralateral side. In these rats, morphological investigations showed distorted neurons, membrane disruption, synaptic damage and myelin vesiculation. Sham operated rats did not show an upregulation of HO-2 expression and the structural changes in the spinal cord were absent. These observations strongly suggest that spinal nerve lesion is associated with an increased production of CO which is somehow contributing to the neurodegenerative changes in the spinal cord, not reported earlier.
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  • 7
    ISSN: 1438-2199
    Keywords: Keywords: Amino acids ; Hyperthermia ; Heat stress ; Brain edema ; Nitric oxide synthase ; Heme oxygenase ; Oxidative stress ; H-290/51 ; Cell injury
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary. Influence of a new anti-oxidant compound H-290/51 on expression of nitric oxide synthase (NOS) and heme oxygenase (HO) enzymes responsible for nitric oxide (NO) and carbon monoxide (CO) production, respectively was examined in the CNS following heat stress in relation to cell injury. Exposure of rats to 4 h heat stress at 38°C in a biological oxygen demand (BOD) incubator (relative humidity 50–55%, wind velocity 20–25 cm/sec) resulted in profound edema and cell injury in many parts of the cerebral cortex, hippocampus, cerebellum, thalamus, hypothalamus and brain stem. Immunostaining of constitutive isoforms of neuronal NOS (nNOS) and HO-2 revealed marked upregulation in damaged and distorted neurons located within the edematous brain regions. Pretreatment with H-290/51 (50 mg/kg, p.o., 30 min before heat stress) significantly reduced the edematous swelling and cell injury and resulted in a marked attenuation of nNOS and HO-2 expression. These observations suggest that upregulation of NOS and HO is associated with cell injury, and the antioxidant compound H-290/51 is neuroprotective in heat stress.
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  • 8
    ISSN: 1436-6215
    Keywords: lung ; development ; vitamin A ; DNA ; RNA ; protein ; rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Der Einfluß einer Beschränkung der Vitamin-A-Zufuhr für das Muttertier auf die biochemische Entwicklung der Lunge des Jungtieres wurde bei Ratten untersucht. Der Vitamin-A-Status der Muttertiere wurde durch niedrige, mittlere und adäquate Gaben von Vitamin A während Trächtigkeit und Säugezeit variiert (6, 40 und 100 μg Retinol/Tag/kg Körpergewicht). Die Ergebnisse zeigen, daß die Beschränkung der Vitamin-A-Zufuhr für das Muttertier das Wachstum und die Entwicklung der Lunge in bezug auf Gewicht, DNA- und Proteingehalt und -biosynthese aus markierten Vorstufen, RNA-Gehalt, Zellgröße und Zellzahl beeinflussen.
    Notes: Summary The effect of maternal vitamin A restriction on the biochemical development of the lung in rats has been studied. The vitamin A status of dams has been varied by supplying low, medium and adequate amounts of vitamin A (6, 40 and 100 μg retinol/day/kg body weight, respectively) during pregnancy and suckling. The results demonstrate that the restricted supply of vitamin A to the mother affected the growth and development of the lung in parameters of tissue weight, DNA and protein levels and their biosynthesis from respective labelled precursors, RNA contents, cell number and cell size.
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  • 9
    ISSN: 1436-6215
    Keywords: RBP secretion ; vitamin A ; carotenoids ; goat ; RBP-Sekretion ; Vitamin A ; Carotinoide ; Ziege
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Die Sekretion von retinolbindendem Protein (RBP) ins Blut von Ziegen wurde nach unterschiedlicher Verabreichung von Vitamin A (Retinylacetat), Β-Carotin und einer Mischung von pflanzlichen Carotinoiden untersucht. Die Zufuhr dieser Verbindungen — entweder in einer einzelnen hohen Dosis oder in der gleichen Menge gleichmäßig auf 4 Tagesdosen verteilt — führte zu einem deutlichen Anstieg der RBP-Sekretion. Diese Sekretion erfolgte in zwei Phasen, von denen eine früh und eine später einsetzte.
    Notes: Summary Studies were conducted on the secretion of retinol-binding protein (RBP) in blood of goats given different treatments of preformed vitamin A, Β-carotene and plant carotenoids. Administration of these sources either in a single massive dose or massive dose split into four equal doses, markedly increased the secretion of RBP in blood. The secretion of RBP in blood occurred at least in two phases, one at early periods and the other at later periods.
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  • 10
    ISSN: 1438-2199
    Keywords: Heat stress ; Nitric oxide ; Cell injury ; Antioxidant ; H-290/51Blood-brain barrier ; Brain edema
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that nitric oxide (NO) is involved in the pathophysiology of brain injury caused by heat stress (HS) was examined using neuronal nitric oxide synthase (NOS) immunohistochemistry in a rat model. In addition, to find out a role of oxidative stress in NOS upregulation and cell injury, the effect of a new antioxidant compound H-290/51 (Astra Hässle, Mälndal, Sweden) was examined in this model. Subjection of conscious young rats to 4 h HS in a biological oxygen demand (BOD) incubator at 38°C resulted in a marked upregulation of NOS in many brain regions compared to control rats kept at room temperature (21 ± 1°C. This NOS immunoreactivity was found mainly in distorted neurons located in the edematous regions not normally showing NOS activity. Breakdown of the blood-brain barrier (BBB) permeability, increase in brain water content and marked neuronal, glial and myelin reaction were common findings in several brain regions exhibiting upregulation of NOS activity. Pretreatment with H-290/51 significantly attenuated the upregulation of NOS in rats subjected to HS. In these animals breakdown of the BBB permeability, edema and cell changes were considerably reduced. Our results suggest that hyperthermic brain injury is associated with a marked upregulation of NOS activity in the CNS and this upregulation of NOS and concomitant cell injury can be reduced by prior treatment with an antioxidant compound H 290/51. These observations indicate that oxidative stress seems to be an important endogenous signals for NOS upregulation and cell reaction in hyperthermic brain injury.
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