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991.
Pasticci MB Floridi P Schiaroli E Stagni GM De Socio GV Longari F Baldelli F 《The new microbiologica》2012,35(2):233-237
Here we report on two consecutive cases of tuberculosis in immunocompetent HIV-negative patients with lingual lesions. In both patients diagnosis was delayed. Disease progressed involving the lungs, lymph nodes and also the brain. Both patients are disease-free at 30 and 22 month follow-up respectively. Isolated Mycobacterium tuberculosis from these patients was multi-susceptible. Tuberculosis lesions of the oral cavity and brain are infrequently diagnosed in immunocompetent subjects from Western countries. Clinicians must take into greater consideration tuberculosis as a possible diagnosis when diagnosing chronic and/or recurrent lingual lesions even in the absence of pulmonary lesions. 相似文献
992.
An in vitro evaluation of the effect of probiotics and prebiotics on the metabolic profile of human microbiota 总被引:1,自引:0,他引:1
In the current study, batch culture fermentations on fecal samples of 3 healthy individuals were performed to assess the effect of the addition of prebiotics (FOS), probiotics (Bifidobacterium longum Bar33 and Lactobacillus helveticus Bar13) and synbiotics (B. longum Bar33 + L. helveticus Bar13 + FOS) on the fecal metabolic profiles. A total of 84 different metabolites belonging to the families of sulfur compounds, nitrogen compounds, aldehydes, ketones, esters, alcohols, phenols, organic acids, and hydrocarbons were detected by GC-MS/SPME analysis. The highest number of metabolites varied in concentration in the models with added FOS and synbiotics, where several metabolic signatures were found in common. The increase of butyrate represented the greatest variation registered after the addition of FOS alone. Following the B. longum Bar33 addition, 2-methyl butyrate underwent the most evident variation. In the batch fermentation with added L. helveticus Bar13, the decrease of pyridine and butandiene was observed together with the increase of 2-methyl-5-ethyl-pyrazine, 2-butanone and butyrate. The modification of the fecal metabolic profiles induced by the simultaneous addition of B. longum Bar33 and L. helveticus Bar13 was very similar to that observed after the supplementation with L. helveticus Bar13, regarding mainly the decrease of pyridine and the increase of butyrate. 相似文献
993.
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
994.
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
995.
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
996.
997.
998.
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
999.
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
1000.
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