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811.
Sabina Cauci Rossella Monte Monica Ropele Caterina Missero Tarcisio Not Franco Quadrifoglio Gianfranco Menestrina 《Molecular microbiology》1993,9(6):1143-1155
The pleomorphic bacterium Gardnerella vaginalis releases in the culture broth a haemolytic exotoxin (Gvh) which is probably a virulence determinant of this unique bacterium, implicated in gynaecological and urological disorders. This 59kDa cytolysin was purified to homogeneity in just one chromatographic step directly from the culture supernatant, a final specific activity up to 1.9 × 106 HU mg?1 being obtained. The toxin-induced lesion on human erythrocytes results from the formation of a pore whose radius is approximately 2.4 nm. The damage is inhibited by osmotic protectants and shows a sigmoidal dose-response profile suggesting an aggregation process of haemolysin molecules on the target membrane to create the functional lesion. The extent and the kinetics of haemolysis are strongly dependent on temperature and an activation energy of 64.0 kJ mol?1 has been derived. Lipid membranes can be very efficient inhibitors of Gvh-haemolysis, being able to bind the toxin quite avidly. The inhibitory effect requires the presence of cholesterol and it is stronger when cholesterol is mixed with negatively charged phospholipids rather than with zwitterionic phospholipids, suggesting that a negative surface potential increases the affinity of the toxin for the lipid bilayer. The functional properties of Gvh have been compared with those of Clostridium perfringens theta-toxin (PFO) and Escherichia coli haemolysin (HlyA), which are representative of widespread haemolysins produced by Gram-positive and Gram-negative bacteria, respectively. The toxin shares several features with the family of the so-called ‘sulphydryl-activated’ cytolysins produced by Gram-positive bacteria, although Gvh does not truly belong to this family, being deactivated by β-mercaptoethanol and being antigenically distinct from them. We report here for the first time the detection in the vaginal fluid of infected women of a specific IgA response against the toxin. 相似文献
812.
Albino Defilippi Gianfranco Piancone Riccardo Costa Laia Silvia Balla Gian Paolo Tibaldi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,656(2)
A method for the determination of isonicotinic acid hydrazide (isoniazid) in milk was developed. Milk was deproteinized with trichloroacetic acid. Isoniazid was condensed with cinnamaldehyde and assayed on a reversed-phase HPLC system, with good sensitivity and accuracy (10 μg/l) with UV detection at 330 nm. Use of solid-phase extraction with a C18 cartridge allows the detection limit to be lowered to 0.1 μg/l with UV detection and confirmation of isoniazid hydrazone from the diode-array UV spectrum. 相似文献
813.
Syntheses are described for two N-benzyloxycarbonylpeptide tert-butoxycarbonylhydrazides which correspond to positions 24–34 and 35–44, respectively, of the primary structure of baker's yeast iso-1-cytochrome c. The two peptide derivatives were coupled via the azide procedure to form the N-benzyloxycarbonylheneicosapeptide tert-butoxycarbonylhydrazide (sequence 24–44). 相似文献
814.
815.
Carlucci Roberto Capezzuto Francesca Cipriano Giulia D’Onghia Gianfranco Fanizza Carmelo Libralato Simone Maglietta Rosalia Maiorano Porzia Sion Letizia Tursi Angelo Ricci Pasquale 《Reviews in Fish Biology and Fisheries》2021,31(1):135-156
Reviews in Fish Biology and Fisheries - The exploitation of fishery resources acts as a driving force on cetaceans both directly, by determining their fishing mortality or injury as by-catch... 相似文献
816.
Awatef Allouch Cristina Di Primio Audrey Paoletti Gabrielle Lê-Bury Frdric Subra Valentina Quercioli Roberta Nardacci Annie David Hla Saïdi Anna Cereseto David M. Ojcius Guillaume Montagnac Florence Niedergang Gianfranco Pancino Asier Saez-Cirion Mauro Piacentini Marie-Lise Gougeon Guido Kroemer Jean-Luc Perfettini 《Cell death and differentiation》2020,27(12):3243
Understanding the viral–host cell interface during HIV-1 infection is a prerequisite for the development of innovative antiviral therapies. Here we show that the suppressor of G2 allele of skp1 (SUGT1) is a permissive factor for human immunodeficiency virus (HIV)-1 infection. Expression of SUGT1 increases in infected cells on human brain sections and in permissive host cells. We found that SUGT1 determines the permissiveness to infection of lymphocytes and macrophages by modulating the nuclear import of the viral genome. More importantly, SUGT1 stabilizes the microtubule plus-ends (+MTs) of host cells (through the modulation of microtubule acetylation and the formation of end-binding protein 1 (EB1) comets). This effect on microtubules favors HIV-1 retrograde trafficking and replication. SUGT1 depletion impairs the replication of HIV-1 patient primary isolates and mutant virus that is resistant to raltegravir antiretroviral agent. Altogether our results identify SUGT1 as a cellular factor involved in the post-entry steps of HIV-1 infection that may be targeted for new therapeutic approaches.Subject terms: Infectious diseases, Immunopathogenesis 相似文献
817.
Gianfranco Adimari Andrea Sinigaglia 《Biometrical journal. Biometrische Zeitschrift》2020,62(6):1463-1475
In medical research, diagnostic tests with continuous values are widely employed to attempt to distinguish between diseased and non-diseased subjects. The diagnostic accuracy of a test (or a biomarker) can be assessed by using the receiver operating characteristic (ROC) curve of the test. To summarize the ROC curve and primarily to determine an “optimal” threshold for test results to use in practice, several approaches may be considered, such as those based on the Youden index, on the so-called close-to-(0,1) point, on the concordance probability and on the symmetry point. In this paper, we focus on the symmetry point-based approach, that simultaneously controls the probabilities of the two types of correct classifications (healthy as healthy and diseased as diseased), and show how to get joint nonparametric confidence regions for the corresponding optimal cutpoint and the associated sensitivity (= specificity) value. Extensive simulation experiments are conducted to evaluate the finite sample performances of the proposed method. Real datasets are also used to illustrate its application. 相似文献
818.