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Lodovica Vergani Marina Fanin Andrea Martinuzzi Andrea Galassi Andrea Appi Rosalba Carrozzo Maurizio Rosa Corrado Angelini 《Molecular and cellular biochemistry》1990,98(1-2):225-230
Summary FABPs in the various tissues play an important role in the intracellular fatty acid transport and metabolism. Reye's syndrome (RS) and multisystemic lipid storage (MLS) are human disorders characterized by a disturbance of lipid metabolism of unknown etiology. We investigated for the first time L-FABP in these two conditions. Affinity purified antibodies against chicken L-FABP were raised in rabbits, and found to cross-react specifically with partially purified human L-FABP. L-FABP content in liver samples of two patients with RS and MLS was investigated by immuno-histochemistry, SDS-PAGE and ELISA. L-FABP immuno-histochemistry showed increased reactivity in the liver of RS patient and normal reactivity in MLS liver. L-FABP increase in RS liver was confirmed by densitometry of SDS-PAGE and ELISA method. By these two methods the increase amounted to 180% and 199% (p < 0.02), respectively, as compared to controls. A possible role of L-FABP in the pathogenesis of RS is discussed. 相似文献
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Maurizio Grimaldi Giacomo Pozzoli Pierluigi Navarra Paolo Preziosi Gennaro Schettini 《Journal of neurochemistry》1994,63(1):344-350
Abstract: In this study we analyzed the involvement of the cyclic AMP (cAMP)-protein kinase A system in the regulation of interleukin 6 production by cultured cortical astrocytes. Vasoactive intestinal peptide strongly increased, in a dose-dependent manner, interleukin 6 production. This effect was reduced when protein kinase A was blocked by KT-5720; it was not affected by calphostin C, a protein kinase C inhibitor. Forskolin caused a concentration-dependent increase in interleukin 6 release that was also inhibited by KT-5720. Because prostaglandins are believed to play a role in interleukin 6 production, we tried to determine whether the stimulatory effects of vasoactive intestinal peptide and forskolin on cytokine release might be mediated by stimulation of prostaglandin production in cortical astrocytes. Vasoactive intestinal peptide did not increase the production of either prostaglandin E2 or F2α. Conversely, forskolin concentration-dependently stimulated the production of both prostaglandins, an effect that was blocked by indomethacin. Indomethacin did not affect either vasoactive intestinal peptide- or forskolin-stimulated interleukin 6 production. To exclude the possibility that prostaglandins participate in interleukin 6 production induced by forskolin, we tested prostaglandins E2 and F2α. The former was completely ineffective in eliciting the cytokine production, whereas prostaglandin F2α slightly increased interleukin 6 production only at the highest concentrations. 8-Bromo-cAMP and dibutyryl-cAMP stimulated interleukin 6 production to a lesser extent than vasoactive intestinal peptide and forskolin. In conclusion, we provide evidence that vasoactive intestinal peptide increases interleukin 6 production by astrocytes through the stimulation of the cAMP-protein kinase A pathway, an effect that is reproduced by cAMP analogues. In addition, we point out that prostaglandins are not involved in vasoactive intestinal peptide- and forskolin-mediated induction of interleukin 6 production in cultured astrocytes. 相似文献
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Maurilio De Felice John Guardiola Werner Schreil Mark Levinthal Maurizio Iaccarino 《Molecular & general genetics : MGG》1977,156(1):9-16
Summary Some of the strains containing mutations in the genes for the acetolactate synthase isoenzymes are temperature sensitive (ts). Suppression of the acetolactate synthase defect due to one of these mutations suppresses also the ts phenotype; moreover, a genetic cross shows that the two phenotypes cannot be dissociated.The ts phenotype is accompanied by a decreased efficiency of transduction with Pl phage. Observations at the light microscope show formation of abnormal cells. Under specific conditions diaminopimelate stimulates growth and restores normal transduction efficiency. The rate of diaminopimelate formed and excreted by non-growing cells decreases when an acetolactate synthase mutation is present.We give evidence that the ts phenotype is due to an increased formation of lysine from diaminopimelate; this causes a starvation for the latter and therefore cell wall abnormalities. In fact, even at the permissive temperature, the lysine pool is 8x increased in a strain with an acetolactate synthase defect, while a slight decrease in the diaminopimelate pool is observed. Moreover, introduction into a ts strain of a mutation in lysA (the gene coding for diaminopimelate decarboxylase) cures the ts phenotype. Finally among the temperature resistant revertants we found some lysine auxotrophs. 相似文献
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Maurizio Rossetto Kingsley W. Dixon Eric Bunn 《In vitro cellular & developmental biology. Plant》1992,28(4):192-196
Summary Aeration of tissue cultured rare Australian plantsConostylis wonganensis S.D. Hopper (Haemodoraceae);Diplolaena andrewsii Ostenf.;Drummondita ericoides Harvey (Rutaceae);Eremophila resinosa F. Muell. (Myoporaceae);Eucalyptus ‘graniticola’ (Myrtaceae);Lechenaultia pulvinaris C. Gardner (goodeniaceae); andSowerbaea multicaulis E. Pritzel (Liliaceae) has been found to reduce vitrification in sensitive species as well as significantly improving shoot
quality and transfer to soil in most study species. A simple 7-mm hole with a double-layer insert of filter paper in the polypropylene
screw lids of the culture vessel decreased shoot vitrification over a 4-wk culture period. The method has implications for
facilitating the tissue culture of other rare Australian plants and reducing the occurrence of this developmental abnormality. 相似文献
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