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V Strippoli

Publications and source records attributed to V Strippoli.

36 records · Page 2Linked to original sources
PubMed1976

Antimycotic activity in vitro and in vivo of a new hydrosoluble polyene antibiotic.

The in vitro and in vivo activity of a new water soluble polyene antibiotic, anmed SPA-S-222, has been studied on numerous Candida and Cryptococcus species. The in vitro tests were carried out in comparison with nystatin and amphotericin B whose antimycotic properties are already well known. The inhibition of "germination" of various strains of Candida albicans was also investigated. The results show that SPA-S-222 has greater antimycotic activity than nystatin or amphotericin B. Tests on the protection afforded by SPA-S-222 in Swiss albino mice infected with C, albicans were satisfactory as regards both the total protective dose and the partial protective dose (P.D. 50%).

Amphotericin B↗
PubMedDate not supplied

Antifungal activity of ketoconazole and other azoles against Malassezia furfur in vitro and in vivo.

The in vitro activity of several antifungal agents (ketoconazole, miconazole, econazole, fenticonazole, itraconazole, fluconazole) in routine clinical use against Malassezia furfur infections has been studied with freshly isolated strains of M. furfur from pityriasis versicolor lesions. The results indicate that the drugs tested exert a good activity, and both ketoconazole and itraconazole appear very active (0.8 mg/l respectively). Hair samples from the beards of volunteer patients affected by pityriasis versicolor but otherwise healthy were examined to determine ketoconazole levels during oral therapy (one or two 200 mg tablets daily). It was shown that the drug progressively accumulates in the beard, reaching levels proportional to the dose administered, although blood levels did not increase in parallel. The study of drug concentration profile has evidenced a long ketoconazole persistence in the beard at therapeutic levels. In conclusion, the possibility of reaching high and lasting ketoconazole levels in the keratin layer of the epidermis indicates that systemic ketoconazole therapy could be useful for eradication of M. furfur in patients affected by pityriasis versicolor.

Adult↗
PubMedDate not supplied

In vivo and in vitro antifungal activity of the polyene derivative SPA-S-753 against encapsulated form of Cryptococcus neoformans.

The in vitro and in vivo activity of SPA-S-753 (N-dimethylaminoacetyl-partricin A 2-dimethylaminoethylamide diaspartate), a new water soluble polyene, was compared with amphotericin B against Cryptococcus neoformans in encapsulated (K) and nonencapsulated (N) morphological forms. In vitro tests against 17 isolates of C. neoformans (in K or N form) showed that SPA-S-753 activity is about ten times higher than that of amphotericin B. In direct contact tests the SPA-S-753 cytocidal action was significantly higher than that of amphotericin B; the K cells are, however, less sensitive to the cytocidal action exerted by the two polyenes even when using concentrations 4-fold higher than those used against the N cells and they present a smaller potassium ion release. The cytocidal activity of the two polyenes is favoured by a low electrolyte concentration and an acid pH. SPA-S-753 microbicidal activity by contact in vivo, in mice infected with C. neoformans N cells by i.p. route, is more powerful than that of amphotericin B. In protection tests in mice infected with 10 LD50 of C. neoformans K cells, SPA-S-753 action is again more powerful, but not to a significant degree, than that of amphotericin B. In conclusion, both substances showed a reduced in vitro and in vivo activity against C. neoformans in the K morphological form. Nevertheless our results demonstrate that SPA-S-753 exerts an antifungal overall activity that is more effective than that of amphotericin B under similar experimental conditions.

Amphotericin B↗
PubMedDate not supplied

[Antimicrobial characteristics of a tincture of dequalinium chloride].

Dequalinium is a quaternary ammonium salt. From about 30 years Dequalinium (D.C.) was used in the treatment of the initial respiratory organs infections. It can be given orally and topically yet it cannot be given systemically cause its probable systemic toxicity. D.C. has a wide range of antimicrobial activity that is extended to Gram positive, Gram negative bacteria, protozoa and yeast. Its mechanism of action is directed to the cytoplasmatic membrane where D.C. caused its damage and consequently release of cellular components. Our study has been evaluated the antimicrobial activity of D.C. both as commercial product that pure substance. We tested 27 Gram positive bacteria, 49 Gram negative bacteria, 83 strains of fungi, we also tested the antimicrobial activity of D.C. commercial product and pure substance against 8 strains of protozoa; Trichomonas vaginalis. The antimicrobial activity was estimated in some experimental conditions, (cultural and no cultural conditions); in these experiments we can observed that the commercial product presents higher activity than pure substance. In cultural condition commercial product presents antimicrobial activity against Gram positive and negative bacteria and yeast; its interesting to evaluate that bacteria, that are resistant to the common antimicrobial agents were inhibited by D.C. tinture and pure substances. Our data exhibit that serum didn't interfere until the 2% concentration with the antimicrobial activity of D.C., moreover this antimicrobial activity is not influenced by the inoculum size until 10(5) cell/ml. D.C. presents higher activity at alkaline pH than acid pH but strains of C. albicans were killed by D.C. at acid pH. In no cultural conditions D.C. has demonstrated a rapid antimicrobial activity in short contact time (15 minute); the cells of some microorganisms were killed in 60 minutes. Against mycelial form, the commercial product demonstrates good activity higher than pure substance. The activity of D.C. against the formation of germ-tube from blastospores of C. albicans in N-acetyl-glucosamine solution (no culture medium) was markedly high; this is very important because in C. albicans the germ-tube production and yeast-mycelial conversion are prominent for pathogenicity and resistance to host defences. Our data demonstrate the good activity of D.C. against Trichomonas vaginalis; we can also observed that the antimicrobial activity of commercial product is higher than pure substance.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMedDate not supplied

[Antimicrobial activity exerted by sodium dichloroisocyanurate].

Sodium dichloroisocyanurate is a chlorinated cleaner. It was used for swimming pool sanitation and for the sterilisation of linen. Not recently ago sodium dichloroisocyanurate has substituted hypochlorite for the sterilisation of infant feeding bottles and teats. Sodium dichloroisocyanurate is soluble in water; this condition causes the hydrolysis of sodium dichloroisocyanurate in hypochlorous acid, that is the active agent, isocyanurate and isocyanurate chlorine. These compounds form a chlorine protein that carry out microbicidal activity. In a toxicology study has been shown that no severe changes in the normal metabolic function occurred, furthermore sodium dichloroisocyanurate has not shown teratogenic effects at the concentration of 200 mg/kg. The antimicrobial activity of sodium dichloroisocyanurate was evaluated against Gram negative bacteria such as E. coli or Salmonella typhimurium and against some fungi. This study illustrates a rapid antimicrobial activity using concentrations. Our study concentrated on the antimicrobial activity of sodium dichloroisocyanurate in some experimental conditions. We tested 66 strains of fungi, 28 Gram positive bacteria and 29 Gram negative bacteria. We also evaluated the antimicrobial activity of sodium dichloroisocyanurate against protozoa such as Trichomonas vaginalis. The antimicrobial activity was evaluated in cultural conditions and non cultural conditions; in these experiments we observed similar action in both the commercial product and pure substance. In cultural conditions sodium dichloroisocyanurate shows a good activity against fungi and bacteria, moreover it can be observed that the serum didn't interfere with its activity. In a non cultural condition the Candida was killed rapidly by the sodium dichloroisocyanurate but this activity is influenced by the growth phase of the yeast. Against mycelial form such as Penicillium and Aspergillus the sodium dichloroisocyanurate needs a longer contact time than yeast form for its activity. It is interesting to note that well known bacteria, that are resistant to the common antimicrobial agents, such as Pseudomonas aeruginosa, were inhibited by sodium dichloroisocyanurate in a rapid bactericidal action. Our data demonstrates that no significant adverse influence on the activity of sodium dichloroisocyanurate was shown by pH and by temperature even if in some experimental conditions increased activity was noticed at pH = 6.6. The sodium dichloroisocyanurate has demonstrated good activity against Trichomonas vaginalis. This fact extends the broad-spectrum activity of sodium dichloroisocyanurate to the protozoa. In conclusion, sodium dichloroisocyanurate has demonstrated a good activity against all tested strains, furthermore its activity did not decrease in the presence of 1% of organic substance (serum etc.).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMedDate not supplied

The antibacterial activity of a new 3-azinomethyl-rifamycin.

The new 3-azinomethyl-rifamycin, SPA-S-565, was shown to exert an effective antibacterial activity in vitro comparable to that of rifampicin. In fact, the antibacterial activity of SPA-S-565 against numerous Gram-positive cocci belonging to Staphylococcus and Streptococcus species as well as against 20 strains of Mycobacterium tuberculosis, was similar to that of rifampicin. In Swiss albino mice intraperitoneally infected with Staphylococcus aureus Oxford strain or Streptococcus pyogenes, the protective activity of SPA-S-565 and rifampicin was quite remarkable, and no significant difference was noted between the two antibiotics. In M. tuberculosis-infected mice treated with the antibacterial agents every seven days, the protection exerted by SPA-S-565 was significantly greater than that exerted by rifampicin.

Animals↗