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1.
A Serrano-Lozano P Morata M Montiel J P Pérez-Aguilar M Morell 《Revista Espanola de Fisiología》1991,47(3):141-145
The L-thyroxine and L-triiodothyronine concentrations in several brain areas (cerebral cortex, brain stem, hypothalamus, total brain and hypophysis) in normal and hypothyroid rats have been studied. Results show that L-thyroxine values at tissue level are inferior in the hypothyroid group, although non-significant with respect to the control group, whereas L-triiodothyronine presents values similar to the hypothyroid group and its control in all the brain regions studied with the exception of hypophysis. These results show that in hypothyroid situations exist a compensatory mechanism for maintaining the adequate L-triiodothyronine levels in several brain areas, although the serum levels are strongly decreased in hypothyroid animals. 相似文献
2.
R J Stockert A G Morell I H Scheinberg 《Biochemical and biophysical research communications》1976,68(3):988-993
Oligosaccharide chains of agalactoorosomucoid, α1-acid glycoprotein from which sialic acid and galactose have been sequentially removed, terminate in N-acetylglucosaminyl residues. This protein is rapidly transferred from the circulation into the liver by a route distinct from that previously demonstrated for a number of galactosyl terminating glycoproteins. 相似文献
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Kristin Kassler Anselm H. C. Horn Heinrich Sticht 《Journal of molecular modeling》2010,16(5):1011-1020
Converging lines of evidence suggest that soluble Aβ-amyloid oligomers play a pivotal role in the pathogenesis of Alzheimer’s
disease, and present direct effectors of synaptic and cognitive dysfunction. Three pathological E22-Aβ-amyloid point mutants
(E22G, E22K, E22Q) and the deletion mutant E22Δ exhibit an enhanced tendency to form prefibrillar aggregates. The present
study assessed the effect of these four mutations using molecular dynamics simulations and subsequent structural and energetic
analyses. Our data shows that E22 plays a unique role in wild type Aβ, since it has a destabilising effect on the oligomer
structure due to electrostatic repulsion between adjacent E22 side chains. Mutations in which E22 is replaced by an uncharged
residue result in higher oligomer stability. This effect is also observed to a lesser extent for the E22K mutation and is
consistent with its lower pathogenicity compared to other mutants. Interestingly, deletion of E22 does not destroy the amyloid
fold but is compensated by local changes in the backbone geometry that allow the preservation of a structurally important
salt bridge. The finding that all mutant oligomers investigated exhibit higher internal stability than the wild type offers
an explanation for the experimentally observed enhanced oligomer formation and stability. 相似文献
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6.
Synthetic magainin analogues with improved antimicrobial activity 总被引:11,自引:0,他引:11
Based on modifications to enhance the alpha-helical structure of the broad spectrum antibiotic magainin 2, a series of analogues have been synthesized which display an increase up to two orders of magnitude in antimicrobial activity and, in the most favorable case, no appreciable increase in hemolytic activity over magainin 1 at the concentrations tested. 相似文献
7.
The enzymatic activities of two "key" enzymes of the glycolytic pathway, pyruvate kinase and lactic dehydrogenase, were studied in seven areas of the brain in male adult rats in states of pharmacologically induced hyper and hypothyroidism. The brain areas were: anterior cortex, adenohypophysis, hypothalamus, amygdaline nucleus, septum, hippocampus and cerebellum. In T3 treated animals, pyruvate kinase activity showed significant increase in all the areas studied while lactic dehydrogenase activity decreased. In propyl-thiouracil treated animals these enzyme activities showed no significant variations from those in animals of the control group. 相似文献
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M Sato M L Schilsky R J Stockert A G Morell I Sternlieb 《The Journal of biological chemistry》1990,265(5):2533-2537
Three polypeptides with apparent Mr = 200,000, 135,000, and 115,000, reacting with antibody to human ceruloplasmin (Cp), were consistently found in sera of normal adult and newborn subjects, patients with Wilson's disease, as well as in the oxidase-active fraction of purified human Cp, resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The concentrations of the three Cp polypeptides were proportional to the total Cp oxidase activity measured in whole serum. Peptide mapping revealed that the three Cp polypeptides were closely related. Cross-linking of Cp135 resulted in dimers with electrophoretic mobility similar to that of Cp200. A common shift in electrophoretic mobility following N-glycanase treatment indicated that all three polypeptides were N-glycosylated, and that the apparent differences in molecular mass could not be related to the carbohydrate moiety. Immunoprecipitates of cell lysates of [35S]cysteine labeled HepG2 cells revealed the presence of two species of newly synthesized Cp polypeptides, Mr 200,000 and 135,000, which were secreted into the media. Secretion of Cp200 by the human liver appears to be physiologic and may be the result of posttranslational modification of Cp135. 相似文献