Elena Banfi

Antimycobacterial Activity of Ionic Fullerene Derivatives

Positively charged fullerene derivatives, moderately soluble in water:DMSO 9:1, have been tested using three strains of Mycobacterium spp. Some compounds inhibit the growth of Mycobacterium tuberculosis, a human clinical isolate, particularly virulent and resistant, at doses as low as 5 microg/mL.

A new flow cytometric assay for the evaluation of phagocytosis and the oxidative burst in whole blood

Phagocytes play an important role in host defence against microorganisms and different techniques are needed to evaluate their functional activities. Here we describe a rapid, simple and reliable one step procedure to measure the phagocytosis rate and oxidative burst activation of both polymorphonuclear leukocytes (PMN) and monocytes, by means of flow cytometry using only small quantities of whole blood. The two species of bacteria employed as test microorganisms, Staphylococcus aureus and Candida albicans showed a somewhat different behaviour. We found that the present method could be used as an alternative test in the diagnosis of chronic granulomatous disease (CGD). Moreover we were able to analyse, in a one step procedure, defective phagocyte functions in a group of paediatric patients suffering from recurrent microbial infections.

Synthesis and antimycobacterial activity of [5-(pyridin-2-yl)-1,3,4-thiadiazol-2-ylthio]acetic acid arylidene-hydrazide derivatives.

[5-(Pyridin-2-yl)-1,3,4-thiadiazol-2-ylthio]acetic acid arylidene-hydrazide derivatives were synthesized and tested for their in vitro antimycobacterial activity. Some compounds showed a feable activity against a strain of Mycobacterium tuberculosis and a strain of Mycobacterium avium.

Synthesis and antimycobacterial activity of 5-aryl-1-isonicotinoyl-3-(pyridin-2-yl)-4,5-dihydro-1H-pyrazole derivatives ☆

5-Aryl-1-isonicotinoyl-3-(pyridin-2-yl)-4,5-dihydro-1H-pyrazole derivatives were synthesized and tested for their in vitro antimycobacterial activity. The compounds showed an interesting activity against a strain of Mycobacterium tuberculosis and a human strain of M. tuberculosis H4.

Synthesis and antimycobacterial activity of (3,4-diaryl-3H-thiazol-2-ylidene)-hydrazide derivatives.

[5-(pyridin-2-yl)-1,3,4-thiadiazol-2-ylthio]acetic acid (3,4-diaryl-3H-thiazol-2-ylidene)-hydrazide derivatives were synthesized and tested for their in vitro antimycobacterial activity. Some compounds showed an interesting activity against a strain of Mycobacterium tuberculosis H(37)Rv and three clinical isolates of M. tuberculosis.

Antifungal and antimycobacterial activity of 1-(3,5-diaryl-4,5-dihydro-1H-pyrazol-4-yl)-1H-imidazole derivatives☆

1-(3,5-Diaryl-4,5-dihydro-1H-pyrazol-4-yl)-1H-imidazole derivatives were synthesized and tested for their in vitro antifungal and antimycobacterial activities. These imidazole derivatives showed an excellent antifungal activity against a clinical strain of Candida albicans and an interesting antitubercular activity against Mycobacterium tuberculosis H(37)Rv reference strain.

Studies on the Interaction between Macrophages and Leptospires

Guinea-pig macrophages exerted no bactericidal activity against either a virulent or a saprophytic strain of leptospira during a 120 min period of contact at 37 degrees C. However, the same macrophages exhibited weak phagocytic powers towards these two strains of leptospira over a similar period of time.

Human eosinophil peroxidase induces surface alteration, killing, and lysis of Mycobacterium tuberculosis.

ABSTRACT The antimycobacterial role of eosinophil peroxidase (EPO), one of the most abundant granule proteins in human eosinophils, was investigated. Our data indicate that purified EPO shows significant inhibitory activity towards Mycobacterium tuberculosis H37Rv. On a molar basis, this activity was similar to that exhibited by neutrophil myeloperoxidase (MPO) and was both dose and time dependent. In contrast to the activity of MPO, which requires H2O2, EPO also exhibited anti-M. tuberculosis activity in the absence of exogenously added peroxide. Morphological evidence confirmed that the mechanism of action of EPO against mycobacteria differs from that of MPO. While MPO kills M. tuberculosis H37Rv exclusively in the presence of hydrogen peroxide, it does not induce morphological changes in the pathogen. In contrast, EPO-treated bacteria frequently had cell wall lesions and eventually underwent lysis, either in the presence or in the absence of H2O2.

Antimycobacterial activity of new 3,5-disubstituted 1,3,4-oxadiazol-2(3H)-one derivatives. Molecular modeling investigations

3H-1,3,4-Oxadiazol-2-one derivatives were synthesized and tested for their in vitro antimycobacterial activity. Oxadiazolone derivatives showed an interesting antimycobacterial activity against the reference strain of Mycobacterium tuberculosis H(37)Rv. Molecular modeling investigations were performed and showed that the active compounds possess all necessary features to target the protein active site of the mycobacterial cytochrome P450-dependent sterol 14alpha-demethylase in the sterol biosynthesis pathway as the calculated free energy of binding were in agreement with the corresponding MIC values.

The Role of Antibodies and Serum Complement in the Interaction between Macrophages and Leptospires

Guinea-pig macrophages exerted bactericidal activity against both a virulent and a saprophytic strain of leptospira in the presence of the homologous IgG. Serum complement alone rendered the saprophytic strain susceptible to phagocytosis by the same macrophages.