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V Strippoli

Publications and source records attributed to V Strippoli.

At least 19 recordsLinked to original sources
PubMed2005

Antifungal activity of Lavandula angustifolia essential oil against Candida albicans yeast and mycelial form.

The antifungal activity of the essential oil of Lavandula angustifolia Mill. (lavender oil) and its main components, linalool and linalyl acetate, was investigated against 50 clinical isolates of Candida albicans (28 oropharyngeal strains, 22 vaginal strains) and C. albicans ATCC 3153. Growth inhibition, killing time and inhibition of germ tube formation were evaluated. The chemical composition of the essential oil was determined by gas chromatography and mass spectrometry. Lavender oil inhibited C. albicans growth: mean minimum inhibitory concentration (MIC) of 0.69% (vol./vol.) (vaginal strains) and 1.04% (oropharyngeal strains); mean MFC of 1.1% (vaginal strains) and 1.8% (oropharyngeal strains). Linalool was more effective than essential oil: mean MIC of 0.09% (vaginal strains) and 0.29% (oropharyngeal strains); mean MFC of 0.1% (vaginal strains) and 0.3% (oropharyngeal strains). Linalyl acetate was almost ineffective. Lavender oil (2%) killed 100% of the C. albicans ATCC 3153 cells within 15 min; linalool (0.5%) killed 100% of the cells within 30 s. The essential oil inhibited germ tube formation (mean MIC of 0.09%), as did the main components (MIC of 0.11% for linalool and 0.08% for linalyl acetate). Both the essential oil and its main components inhibited hyphal elongation of C. albicans ATCC 3153 (about 50% inhibition at 0.016% with each substance). Lavender oil shows both fungistatic and fungicidal activity against C. albicans strains. At lower concentrations, it inhibits germ tube formation and hyphal elongation, indicating that it is effective against C. albicans dimorphism and may thus reduce fungal progression and the spread of infection in host tissues.

Antifungal Agents↗
PubMed2003

Effect of propolis on virulence factors of Candida albicans.

Propolis is a resinous substance collected by honeybees from plant sources. Its antimicrobial activity has been well documented but little is specifically known about its activity on virulence factors of Candida albicans. The aim of this work was therefore to evaluate in vitro the propolis effect on yeast-mycelial conversion (Y-M), extracellular phospholipase activity and fungal adhesion to epithelial cells. The two propolis samples used significantly inhibited the C. albicans strains tested, showing a rapid (between 30 seconds and 15 minutes), dose-dependent cytocidal activity and an inhibitory effect on Y-M conversion at a concentration of 0.22 mg/ml. Moreover, the hyphal length was reduced even at lower propolis concentration. Propolis also caused a dose- and time-dependent inhibition of phospholipase activity. No clear effect was shown on adherence to buccal epithelial cells and surface structure hydrophobicity, but damage to the plasma membrane structure was demonstrated with the Propidium Iodide test.

Anti-Infective Agents↗
PubMed2001

In vitro activity of tea tree oil against Candida albicans mycelial conversion and other pathogenic fungi.

The antifungal activity of Melaleuca alternifolia Maiden (Myrtaceae) essential oil against yeasts (Candida spp., Schizosaccharomyces pombe, Debaryomyces hansenii) and dermatophytes (Microsporum spp. and Tricophyton spp.) is reported. We focused on the ability of tea tree oil to inhibit Candida albicans conversion from the yeast to the pathogenic mycelial form. Moreover we carried out broth microdilution test and contact tests to evaluate the killing time. M. alternifolia essential oil inhibited the conversion of C. albicans from yeast to the mycelial form at a concentration of 0.16% (v/v). The minimum inhibitory concentrations (MICs) ranged from 0.12% to 0.50% (v/v) for yeasts and 0.12% to 1% (v/v) for dermatophytes; the cytocidal activity was generally expressed at the same concentration. These results, if considered along with the lipophilic nature of the oil which enables it to penetrate the skin, suggest it may be suitable for topical therapeutic use in the treatment of fungal mucosal and cutaneous infections.

Anti-Infective Agents, Local↗
PubMed2000

Propyl gallate increases in vitro antifungal imidazole activity against Candida albicans.

We looked at the in vitro effect of an antioxidant, propyl gallate (PG), on the antifungal activity of miconazole sulphosalicylate, econazole sulphosalicylate and ketoconazole against 40 clinical isolates of Candida albicans. The combination of imidazole and PG gave MIC values 10-150 times lower than those of imidazole alone. The optimal conditions for this enhanced activity were pH 6.2-8.0 and a fungal cell concentration lower than 3 x 10(5) cells/ml. The mechanism of the interaction between imidazole and PG is not known but may be as a result of an effect of PG on the P-450 cytochrome. Theoretically this combination could reduce the side effects of long treatment with imidazoles and lower the risk of resistance to these antifungal drugs.

Antifungal Agents↗
PubMed2000

Anticandidal activity of SPA-S-843, a new polyenic drug.

The activity of a new, soluble and stable polyene (SPA-S-843) against Candida albicans was assessed by contact and culture tests and by inhibition of germ-tube formation. The drug demonstrated a higher contact activity and lower MICs than amphotericin B. This antimicrobial activity was more evident under acid pH and low ionic strength. In addition, the ability of SPA-S-843 to inhibit Candida sp. conversion from yeast to mycelial form was evident at low drug concentrations (0.25-0.62 mg/L).

Amphotericin B↗
PubMed1995

Antifungal agents. 9. 3-Aryl-4-[alpha-(1H-imidazol-1-yl)arylmethyl]pyrroles: a new class of potent anti-Candida agents.

A new class of potent antifungal agents, namely, 3-aryl-4-[alpha-(1H-imidazol-1-yl)arylmethyl]-pyrroles, is described. These compounds are related to bifonazole and pyrrolnitrin, two compounds belonging to the class of antimycotic drugs. The synthesis of the title pyrroles has been performed starting from 1,3-diaryl-2-propen-1-ones, which were reacted with tosylmethyl isocyanide to give 3-aroyl-4-arylpyrroles. Reduction of the resulting compounds by lithium aluminum hydride furnished the related alcohols, which were treated with 1,1'-carbonyldimidazole to afford the required imidazole derivatives. Forty-four new pyrroles which incorporate an (arylmethyl)imidazole moiety in the 3-arylpyrrole structure were prepared by the above procedure and tested in vitro against Candida albicans and Candida spp. Among test compounds, 10 were found to be highly active against C. albicans. The most active derivative (27) was twice as potent (MIC90) as bifonazole, and its activity was 4 times greater than those of miconazole and ketoconazole. The other nine compounds showed antifungal activity of the same order of that of bifonazole and were ca. 2 times as active as miconazole and ketoconazole. Derivatives 21 and 27 tested in vivo against C. albicans A170 were shown to be highly effective in rabbit skin candidosis. Pharmacological studies on compounds 27 and other related pyrroles (19, 35, 36, 38, 39, and 49) are in progress to select one of them as a potential candidate for clinical experiments.

Adult↗
PubMed1991

Antimicrobial contact activity of econazole sulfosalicylate.

The aim of this investigation was to compare the contact action of econazole sulfosalicylate (E-SSA) on mycetes (Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Trichophyton rubrum, T. cutaneum, Pityrosporum sp.), Gram-positive bacteria (Staphylococcus aureus, Streptococcus faecalis) and Gram-negative bacteria (Escherichia coli, Citrobacter freundii) with that exerted by econazole nitrate (E-NIT). The results show E-SSA activity greater than E-NIT (in particular against mycetes and Gram-negative bacteria). The E-SSA contact activity trials illustrated certain properties of this imidazole sulfosolicylate such as: absence of latency time, antimicrobial activity proportional to its concentration, when a high concentration is used, given the limiting influence of pH and ionic strength of the medium. The higher E-SSA contact activity, in relation to E-NIT, can be correlated to its greater lipophylia considering also the lipophylic properties of SSA and the scarce dissociation of E-SSA.

Aspergillus fumigatus↗
PubMed1991

Increased in vitro sensitivity of Candida albicans to fluconazole.

Sodium dioctyl sulfosuccinate (SDSS), an anionic surfactant used at a non-antimicrobial concentration, increased the sensitivity of Candida albicans to fluconazole in complex media (such as Sabouraud). The conditions were assessed to determine the in vitro sensitivity to fluconazole. In this connection, the use of a liquid medium at a non-alkaline pH is important. The presence of SDSS in complex media does not seem to affect the neutralization of a particular substances but favours the activity of fluconazole.

Candida albicans↗
PubMed1990

Investigations of the activity by contact of miconazole sulfosalicylate.

The in-vitro antimicrobial activity of miconazole sulfosalicylate (M.SSA) has been investigated on mycetes (Candida albicans, Cryptococcus neoformans, Aspergillus niger, Trichophyton mentagrophytes), Gram-positive bacteria (Staphylococcus aureus, Streptococcus faecalis) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens and Proteus vulgaris) in comparison with miconazole nitrate (M.NIT). The results showed M.SSA has a greater activity than M.NIT, particularly on mycetes and Gram-negative bacteria. The study of activity by contact with M.SSA showed some characteristics of this sulfosalicylate imidazole, such as the lack of a latency time, an antimicrobic action related directly to the concentration, the limited influence of pH and ionic strength of medium used. The greater activity by contact of M.SSA than M.NIT could be related to its higher lipophilia (due also to the lipophilic characteristics of SSA) and, therefore, to increased interaction with the cell membrane.

Candida albicans↗
PubMed1988

Itraconazole: increased activity by chlorhexidine.

Chlorhexidine increases the activity of itraconazole against Candida isolates; itraconazole-chlorhexidine combinations show synergistic activity in culture media. The activity of itraconazole is discussed.

Animals↗
PubMed1988

Itraconazole activity against fungal germination.

Itraconazole was found to be superior to ketoconazole in its antifungal activity in vitro against Hyphomycetes and Candida. In particular, complete inhibition of germination of Candida albicans and Aspergillus spp. by a lower dose of itraconazole can explain the better activity in vivo of this drug.

Antifungal Agents↗
PubMed1988

A study of the antifungal activity of LY121019, a new echinocandin derivative.

LY121019 is a cyclic peptide antibiotic of the echinocandin group, which is characterized by strong anti-Candida activity (in particular against Candida albicans) as well as by low experimental toxicity. Its anti-Candida activity is thought to be due to an inhibition of the synthesis of beta-glucan, an essential cell wall polysaccharide. The different composition of culture media or the presence of animal serum did not show adverse effects on LY121019's anti-Candida activity and the addition of reducing compounds such as cysteine and hydroquinone did not manifest a negative influence. Analogously the anti-Candida activity was not influenced when C. albicans was grown under aeration. The activity of LY121019 was very high against the mycelial form of C. albicans even when this form was developed in the presence of animal serum.

Antifungal Agents↗
PubMed1986

Microbiological perspective of ketoconazole.

The analysis of the results obtained in our trials, which took into account different experimental conditions, suggests that ketoconazole is a very effective anti-Candida drug. In particular, ketoconazole inhibits the development of the hyphal form of C. albicans which is highly invasive. In our trials, we were also able to demonstrate that it is possible to extend ketoconazole's range of action to gram-negative bacteria, if the drug is used in appropriate pharmaceutical forms. Moreover, its in vivo efficacy against dermatophytes and ifomycetes can also be explained by its ability to concentrate in keratinized tissues. From the investigations carried out on leukocyte populations, it has also been demonstrated that ketoconazole does not negatively interfere with the cell defense mechanisms of the host. In fact, the opsonic index and intraphagocytic killing do not significantly change in the presence of ketoconazole in therapeutic doses.

Adult↗
PubMed1984

In vitro and in vivo antifungal activity of the combination methylpartricin-5-fluorocytosine.

In vitro studies on the antifungal activity exerted by the combinations SPA-S-222 (a hydrosoluble derivative of the polyene antibiotic methylpartricin) and 5-fluorocytosine evidence a favourable interaction against the formation of germ-tube in Candida albicans; against Cryptococcus neoformans and 5FC induced-resistant strains of Candida albicans. In the experimental infections with Candida albicans and Cryptococcus neoformans a significantly favourable interaction was exerted by polyene-5FC combinations.

Animals↗
PubMed1981

[Effect of propyl gallate on the antibacterial activity of meclocycline sulfosalicylate].

Propyl gallate shows little antibacterial activity however it markedly potentiates the activity of meclocycline against Pseudomonas, Proteus, Serratia, Escherichia coli and Klebsiella strains. The potentiating effect of propyl gallate is seen especially with resistant strains whereas sensitive strains of Salmonella do not manifest a potentiating effect on meclocycline by propyl gallate. The mechanism of action of propyl gallate is discussed.

Bacteria↗
PubMed1978

Effect of a tetracycline antibiotic on the experimental pathogenicity of Cryptococcus neoformans.

The pathogenicity of three stains of Cryptococcus neoformans was experimentally tested by intradermal inoculations into albino rabbits and intraperitoneally into mice. A relationship was found between the number of inoculated cells and the diameter of dermal lesion; moreover, a typical kinetics of lesion evolution and healing has been shown. Treatment of rabbits with deoxytetracycline did not dramatically influence the behavior of dermal lesions. However, in experiments dealing with strain Vi selected for its enhanced dermotropism, the antibiotic did significantly provoke a diminition of the inflammatory area. In mice, the antibiotic caused a marked increase in mortality (as evaluated by both LD50 values and rate of mortality). Neither in rabbits nor in mice, however, were we able to detect a significant effect of the drug on the dissemination of C. neoformans cells in internal organs. There is no simple explanation for the reported observations but it is possible that local factors in the derma or an aspecific antiinflammatory action of deoxytetracycline are responsible for the unusual response of dermal experimental infection to antibiotic treatment.

Animals↗