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991.
Dina Manetti Lorenzo Di Cesare Mannelli Silvia Dei Luca Guandalini Elisabetta Martini Martina Banchelli Carla Ghelardini 《Bioorganic & medicinal chemistry letters》2009,19(8):2224-2229
This paper documents a serious problem met during the testing of Gi protein-activating properties of a new series of synthetic compounds by measuring the induced binding of [35S]GTPγS to different subtypes of Gi protein. The problem arose from the strong affinity between [35S]GTPγS and the tested compounds, that are characterized by several (2–4) positive charges and high lipophilicity. Apparently, such affinity yields insoluble, labelled complexes that, also in the absence of Gi protein, are retained on the filters and give rise to false positive results. 相似文献
992.
Calcareous nannofossil changes during the late Callovian–early Oxfordian cooling phase 总被引:2,自引:2,他引:0
Fabrizio Tremolada Elisabetta Erba Bas van de Schootbrugge Emanuela Mattioli 《Marine Micropaleontology》2006,59(3-4):197-209
Calcareous nannofossil quantitative and biostratigraphic analyses integrated with carbon and oxygen stable isotopes were carried out on the core ANDRA (Agence Nationale pour la gestion des Déchets Radio-Actifs—FRANCE) HTM 102 across the Callovian/Oxfordian boundary drilled at Cirfontaines-en-Ornois, Départment de Haute-Marne, eastern France. Calcareous nannofossil assemblages at the Callovian–Oxfordian transition are dominated by the genus Watznaueria. An increase in abundance of Biscutum spp. and A-group, which consists of Axopodorhabdus spp. (A. atavus, A. rahla, and A. cylindratus), Podorhabdus grassei, Octopodorhabdus decussatus, Hexapodorhabdus cuvillieri (family Axopodorhabdaceae), and Triscutum spp., correlates with a significant positive excursion in δ18O suggesting that these groups were probably adapted to cooler surface waters. A positive increase in δ13C values is coupled with high abundances of eutrophic taxa such as Zeughrabdotus erectus, Biscutum spp., and small-sized Watznaueria britannica, and a decrease in abundance of the big and oligotrophic taxa Schizosphaerella punctulata and Watznaueria manivitae. Climate cooling across the Callovian/Oxfordian boundary probably triggered a breakdown in stratification of surface waters leading to more intense nutrient recycling and higher primary productivity that favoured the shift in abundance of small-sized eutrophic taxa in the East Paris Basin. 相似文献
993.
Marina Cinco Elena Banfi Elisabetta Ruaro Diana Crevatin Daniele Crotti 《FEMS microbiology letters》1984,21(3):347-351
Abstract 14 strains of Campylobacter isolated from humans and birds were tested for adhesion on intestine cell line. All the strains showed quick adhesion which was inhibited by l -fucose (6-deoxy- l -galactopyranose), among the sugars and lectins used in the adhesion inhibition assay. Inhibition was a function of l -fucose concentration and was not complete, suggesting that beside l -fucose other receptors—or nonspecific interactions—may cooperate in the cell binding by Campylobacter . 相似文献
994.
995.
996.
Lucio Cariello Marina De Nicola Giudici Elisabetta Tosti Laura Zanetti 《Molecular reproduction and development》1982,5(2):161-166
In this paper we report on the mechanism of action of bonellin on sea urchin eggs. Bonellin acts in the same way as porphyrins, ie, by causing the crosslinking of membrane proteins and the peroxocompounds formation. A possible role of membrane organization related to cleavage formation is discussed. 相似文献
997.
Effect of polyunsaturated fatty acids on endocannabinoid and N-acyl-ethanolamine levels in mouse adipocytes 总被引:1,自引:0,他引:1
Matias I Carta G Murru E Petrosino S Banni S Di Marzo V 《Biochimica et biophysica acta》2008,1781(1-2):52-60
The tissue concentrations of the endocannabinoids, 2-arachidonoylglycerol (2-AG) and N-arachidonoyl-ethanolamine (anandamide), are altered in the adipose tissue of mice fed a high fat diet. We have investigated here the effect on endocannabinoid levels of incubation of mouse 3T3-F442A adipocytes with several free polyunstaurated fatty acids (PUFAs), including linolenic acid (LA), alpha-linolenic acid (ALA), arachidonic acid (AA) and docosahexaenoic acid (DHA), as well as oleic acid (OA) and palmitic acid (PA). By using mass spectrometric methods, we quantified the levels of endocannabinoids, of two anandamide congeners, N-palmitoyl-ethanolamine (PEA) and N-oleoyl-ethanolamine (OEA), and of fatty acids esterified in triacylglycerols or phospholipids, which act as 2-AG and/or N-acyl-ethanolamine precursors. Incubation with AA strongly elevated 2-AG levels and the amounts of AA esterified in triacylglycerols and on glycerol carbon atom 2 (sn-2), but not 1 (sn-1), in phospholipids. Incubation with DHA decreased 2-AG and anandamide levels and the amounts of AA esterified on both the sn-2 and sn-1 position of phospholipids, but not on triacylglycerols. PEA levels augmented following incubation of adipocytes with OA and PA, with no corresponding changes in phospholipids and triacylglycerols. We suggest that dietary PUFAs might modulate the levels of adipocyte phospholipids that act as endocannabinoid precursors. 相似文献
998.
Mattioli E Columbaro M Capanni C Santi S Maraldi NM D'Apice MR Novelli G Riccio M Squarzoni S Foisner R Lattanzi G 《Experimental cell research》2008,314(3):453-462
Increasing interest in drugs acting on prelamin A has derived from the finding of prelamin A involvement in severe laminopathies. Amelioration of the nuclear morphology by inhibitors of prelamin A farnesylation has been widely reported in progeroid laminopathies. We investigated the effects on chromatin organization of two drugs inhibiting prelamin A processing by an ultrastructural and biochemical approach. The farnesyltransferase inhibitor FTI-277 and the non-peptidomimetic drug N-acetyl-S-farnesyl-l-cysteine methylester (AFCMe) were administered to cultured control human fibroblasts for 6 or 18 h. FTI-277 interferes with protein farnesylation causing accumulation of non-farnesylated prelamin A, while AFCMe impairs the last cleavage of the lamin A precursor and is expected to accumulate farnesylated prelamin A. FTI-277 caused redistribution of heterochromatin domains at the nuclear interior, while AFCMe caused loss of heterochromatin domains, increase of nuclear size and nuclear lamina thickening. At the biochemical level, heterochromatin-associated proteins and LAP2 alpha were clustered at the nuclear interior following FTI-277 treatment, while they were unevenly distributed or absent in AFCMe-treated nuclei. The reported effects show that chromatin is an immediate target of FTI-277 and AFCMe and that dramatic remodeling of chromatin domains occurs following treatment with the drugs. These effects appear to depend, at least in part, on the accumulation of prelamin A forms, since impairment of prelamin A accumulation, here obtained by 5-azadeoxycytidine treatment, abolishes the chromatin effects. These results may be used to evaluate downstream effects of FTIs or other prelamin A inhibitors potentially useful for the therapy of laminopathies. 相似文献
999.
Siracusano A Riganò R Ortona E Profumo E Margutti P Buttari B Delunardo F Teggi A 《Experimental parasitology》2008,119(4):483-489
The pathologic events that ensue after humans ingest the eggs of Echinococcus granulosus and continue while cystic echinococcosis develops, provide an excellent example illustrating the evasive strategies helminth parasites use to develop, progress and cause chronic disease. The hydatid cyst secretes and exposes numerous immunomodulatory molecules to the host’s immune system. By characterizing these molecules we can understand the mechanisms that E. granulosus uses for increasing the efficiency and persistency of infection in the host. These molecules modulate both the innate and adaptive arms of the immune response and appear to target cellular and humoral responses. In this review, we discuss recent advances in the immunobiology of host-E. granulosus interactions that provide intriguing insights into the complex interplay between host and parasite that ultimately facilitates parasite survival. 相似文献
1000.