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991.
Knecht E Criado-García O Aguado C Gayarre J Duran-Trio L Garcia-Cabrero AM Vernia S San Millán B Heredia M Romá-Mateo C Mouron S Juana-López L Domínguez M Navarro C Serratosa JM Sanchez M Sanz P Bovolenta P Rodríguez de Córdoba S 《Autophagy》2012,8(4):701-703
Lafora disease (LD), a fatal neurodegenerative disorder characterized by intracellular inclusions called Lafora bodies (LBs), is caused by recessive loss-of-function mutations in the genes encoding either laforin or malin. Previous studies suggested a role of these proteins in regulating glycogen biosynthesis, in glycogen dephosphorylation and in the modulation of intracellular proteolytic systems. However, the contribution of each of these processes to LD pathogenesis is unclear. Here we review our recent finding that dysfunction of autophagy is a common feature of both laforin- and malin-deficient mice, preceding other pathological manifestations. We propose that autophagy plays a primary role in LD pathogenesis and is a potential target for its treatment. 相似文献
992.
993.
994.
M. C. Espejo-Iba ez M. P. Sanchez M. D. S nchez-Y lamo 《Biochemical Systematics and Ecology》1994,22(8):827-833
Phaseolus vulgaris is an important crop species. The cultivated common bean derives from wild forms in two independent domestication centers in Mesoamerica and South America. We report a study of electrophoretic patterns of seven isoenzymatic systems in 29 samples of P. vulgaris seeds. Nineteen of them are from northern Spain, four are from Mesoamerican and six are South American forms. The isoenzymatic activity of esterases, cytochrome c oxidase, acid phosphatase, alkaline phosphatase, alcohol dehydrogenase, shikimate dehydrogenase and glutamate oxaloacetic transaminase were studied. On the basis of electrophoretic patterns of seed isoenzymes, four groups can be recognized using clustering procedures (UPGMA). Comparing this biochemical information with previous morpho-agronomic studies, the possible primary domestication centers of the cultivars are discussed. 相似文献
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996.
S Meshinchi J F Grippo E R Sanchez E H Bresnick W B Pratt 《The Journal of biological chemistry》1988,263(32):16809-16817
Boiled cytosols prepared from a wide variety of sources contain a low Mr factor that inhibits glucocorticoid receptor transformation to the DNA-binding state (Leach, K.L., Grippo, J.F., Housley, P.R., Dahmer, M.K., Salive, M.E., and Pratt, W.B. (1982) J. Biol. Chem. 257, 381-388). In this work, we show that this endogenous factor, which is partially purified from rat liver, produces all of the effects of the group VI-A transition metal oxyanions molybdate and vanadate on the structure and function of glucocorticoid receptors in cytosol preparations. Like molybdate, the endogenous factor behaves as a strong anion with an apparent Mr of 340 on Bio-Gel P-2, and it binds to both hydroxylapatite and Chelex 100 resins. The receptor stabilizing activity of the factor is completely stable to heating at 320 degrees C for 1 h. The small size, profound heat stability, and absorption by a metal chelating resin strongly suggest that the factor is an endogenous metal anion. As reduction of the concentration of the factor in cytosol promotes generation of the DNA-binding form of the receptor, we suggest that this endogenous metal anion interacts with the receptor to stabilize the 9 S complex and maintain the receptor in its untransformed, non-DNA-binding state. We propose that molybdate and vanadate may exert their effects on the untransformed receptor by interacting with the binding site for the endogenous metal anion. 相似文献
997.
Antonio Gomez Sanchez Manuel Mancera Francisco Rosado Juana Bellanato 《Carbohydrate research》1984,134(1):63-74
3,4,5,6,7-Penta-O-acetyl-1,2-dideoxy-1-nitro-d-gluco- and -d-galacto-hept-1-enitol and 3,4,5,6-tetra-O-acetyl-1,2-dideoxy-1-nitro-d-xylo-hex-1-enitol react with 3-aminocrotonic esters, yielding mixtures of the epimeric Michael adducts. These are thermally stable, and do not cyclize to pyrroles. The structures, configurations, and conformations of these compounds were established on the basis of their spectroscopic and X-ray crystallographic data. The intramolecularly bonded, (Z) configuration was deduced for all of them. Mild hydrolysis of adducts with acid yields the corresponding 2-(nitromethylpolyacetoxyalkyl)acetoacetates. 相似文献
998.
E. García-Vazquez A. R. Linde G. Blanco J. A. Sanchez E. Vázquez J. Rubio 《Journal of fish biology》1988,33(4):581-587
The karyotypes of two samples of Salmo salar fry used to repopulate the rivers of Asturias (northern Spain) during 1986 were analysed: chromosomal polymorphism differed significantly between them. The need to repopulate with non-heterogeneous stocks is suggested. 相似文献
999.
F Garcia-Maroto A Castagnaro P Sanchez de la Hoz C Mara?a P Carbonero F García-Olmedo 《FEBS letters》1991,287(1-2):67-70
Nucleotide sequences encoding signal peptides from the precursors of alpha-amylase/trypsin inhibitors from cereals are homologous to those corresponding to the precursors of thaumatin II and of plastocyanins. Non-synonymous (KA) and synonymous (KS) rates of nucleotide substitutions have been calculated for all possible binary combinations. Extreme variation in KA/KS ratios has been observed; from the 0.167 average found within the plastocyanin family to an average of 1.90 calculated for the inhibitors/thaumatin II transition. A similar calculation has been carried out for the signal peptide sequences of thionins, which are unrelated to those of the alpha-amylase/trypsin inhibitor family, and an average KA/KS of 0.12 has been obtained. This variation can be largely explained in terms of an empirical index of stability related to amino acid composition and seems to be independent of functional constraints. 相似文献
1000.
Urs Sprecher Peter Mohr Rainer E. Martin Hans Peter Maerki Rubén Alvarez Sanchez Alfred Binggeli Basil Künnecke Andreas D. Christ 《Regulatory peptides》2010,159(1-3):19-27
BackgroundSomatostatin regulates numerous endocrine processes, including glucose homeostasis. The contribution and effects of the 5 somatostatin receptors are still unclear, in part due to the lack of suitable subtype specific receptor antagonists. We explored the effects of two novel, non-peptidic, orally bioavailable somatostatin receptor subtype 5 antagonists named Compound A and Compound B on glycemia in animal models of type 2 diabetes after an initial in vitro characterization.Methods and resultsCompound A led to a dose-dependent decrease in glucose and insulin excursions during an OGTT in Zucker (fa/fa) rats after single treatment by up to 17% and 49%, respectively. Diet-induced obese mice showed after three weeks treatment with compounds A and B a dose-dependent decrease of the glucose excursion of up to 45% and 37%, respectively. In contrast to the acute effect observed in Zucker rats, Compound A showed a dose-dependent insulin increase by up to 72%, whereas body weight, liver triglycerides, ALT and AST were dose-dependently decreased.ConclusionsSSTR5 antagonists have the potential for short- and long-term improvements of the glucose homeostasis in rodent models of type 2 diabetes.Further work on the mechanism and the relevance for human disease is warranted. 相似文献