Search results for " sensitivity"
showing 10 items of 947 documents
Characterization of the antimicrobial susceptibility of fungi responsible for onychomycosis in Spain
2010
Due to the increase of choices relative to antifungals, there is a need to improve the standardization of in vitro methods used to determine the antifungal susceptibility of fungal pathogens. Our study evaluated the in vitro susceptibility of filamentous fungi isolated from patients with toenail onychomycosis against itraconazole, ciclopirox, eberconazole, fluconazole and terbinafine. The minimum inhibitory concentration (MIC) of these antifungal agents was determined with 100 isolates, including dermatophytes (70 strains) and non-dermatophyte molds (30 strains). The susceptibility of fungal isolates was measured by using a technique modified for dermatophytes (0.5 × 10(3)-0.5 × 10(4) conid…
Peptides of the Constant Region of Antibodies Display Fungicidal Activity
2012
Synthetic peptides with sequences identical to fragments of the constant region of different classes (IgG, IgM, IgA) of antibodies (Fc-peptides) exerted a fungicidal activity in vitro against pathogenic yeasts, such as Candida albicans, Candida glabrata, Cryptococcus neoformans, and Malassezia furfur, including caspofungin and triazole resistant strains. Alanine-substituted derivatives of fungicidal Fc-peptides, tested to evaluate the critical role of each residue, displayed unaltered, increased or decreased candidacidal activity in vitro. An Fc-peptide, included in all human IgGs, displayed a therapeutic effect against experimental mucosal and systemic candidiasis in mouse models. It is in…
A New Phenanthrene Glycoside and Other Constituents from Dioscorea opposita
2005
Phytochemical investigation of the rhizome of Dioscorea opposita has led to the isolation of a new phenanthrene glycoside, 3,4,6-trihydroxyphenanthrene-3-O-beta-D-glucopyranoside (1), and five known compounds, soyacerebroside I (2), adenosine (3), beta-sitosterol (4), palmitic acid (5) and palmitoyloleoylphosphatidylcholine (6). Their structures were determined by spectroscopic methods, including 1D- and 2D-NMR. Compounds 1-6 exhibited no antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata and C. tropicalis.
Synthesis and antimicrobial activity of new bromine-rich pyrrole derivatives related to monodeoxypyoluteorin
2006
The synthesis and antimicrobial activity of new pyrrole derivatives structurally related to monodeoxypyoluteorin are described. The insertion of a keto or methylene spacer between the phenol group and the pyrroloyl moiety of brominated 2-(2'-hydroxybenzoyl)pyrroles leads to a decrease of the antibacterial activity.
Antifungal steroid saponins from Dioscorea cayenensis.
2004
From the rhizomes of Dioscorea cayenensis Lam.-Holl (Dioscoreaceae), the new 26- O- beta- D-glucopyranosyl-22-methoxy-3 beta,26-dihydroxy-25( R)-furost-5-en-3- O- alpha- L-rhamnopyranosyl-(1-->4)- alpha- L-rhamnopyranosyl-(1-->4)-[ alpha- L-rhamnopyranosyl-(1-->2)]- beta- D-glucopyranoside ( 1) was isolated together with the known dioscin ( 2) and diosgenin 3- O- alpha- L-rhamnopyranosyl-(1-->4)- alpha- L-rhamnopyranosyl-(1-->4)-[ alpha- L-rhamnopyranosyl-(1-->2)]- beta- D-glucopyranoside ( 3). Their structures were established on the basis of spectral data. Compound 2 exhibited antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata and C. tropicalis (MICs of …
Identification of Novel Hexapeptides Bioactive against Phytopathogenic Fungi through Screening of a Synthetic Peptide Combinatorial Library
2002
The purpose of the present study was to improve the antifungal activity against selected phytopathogenic fungi of the previously identified hexapeptide PAF19. We describe some properties of a set of novel synthetic hexapeptides whose D-amino acid sequences were obtained through screening of a synthetic peptide combinatorial library in a positional scanning format. As a result of the screening, 12 putative bioactive peptides were identified, synthesized, and assayed. The peptides PAF26 (Ac-rkkwfw-NH(2)), PAF32 (Ac-rkwhfw-NH(2)), and PAF34 (Ac-rkwlfw-NH(2)) showed stronger activity than PAF19 against isolates of Penicillium digitatum, Penicillium italicum, and Botrytis cinerea. PAF26 and PAF3…
A Novel Series of Acylhydrazones as Potential Anti-Candida Agents: Design, Synthesis, Biological Evaluation and In Silico Studies
2019
In the context of an increased incidence of invasive fungal diseases, there is an imperative need of new antifungal drugs with improved activity and safety profiles. A novel series of acylhydrazones bearing a 1,4-phenylene-bisthiazole scaffold was designed based on an analysis of structures known to possess anti-Candida activity obtained from a literature review. Nine final compounds were synthesized and evaluated in vitro for their inhibitory activity against various strains of Candida spp. The anti-Candida activity assay revealed that some of the new compounds are as active as fluconazole against most of the tested strains. A molecular docking study was conducted in order to evaluate the …
New antifungals selected by molecular topology.
1999
Abstract Molecular topology has been applied to find the new lead antimycotic compounds. Among the selected compounds stands out 3,3′-(4,4′ - Biphenylene)bis(2,5-diphenyl-2H-tetrazolium chloride), Benztropine mesylate and Dicyclopentamethylenethiuram disulphide, with minimum inhibitory concentrations between 1.6 and 2 μg / mL.
Synthesis and antimicrobial activity of new 3-(1-R-3(5)-methyl-4-nitroso-1H-5(3)-pyrazolyl)-5-methylisoxazoles.
2000
A number of new 3-(1-R-3(5)-methyl-4-nitroso-1H-5(3)-pyrazolyl)-5-methylisoxazoles 6a-g (7b-f) were synthesized and tested for antibacterial and antifungal activity. Some of these compounds displayed antifungal activity at non-cytotoxic concentrations. Derivative 6c was 9 times more potent in vitro than miconazole and 20 times more selective against C. neoformans. 6c was also 8- and 125-fold more potent than amphotericin B and fluconazole, respectively. None of the compounds was active against bacteria. Preliminary structure-activity relationship (SAR) studies showed that the NO group at position 4 of the pyrazole ring is essential for the activity. Lipophilicity of the pyrazole moiety, N-a…
Steroidal saponins from Smilax medica and their antifungal activity.
2005
Three new steroidal saponins (1-3) were isolated from the roots of Smilax medica, together with the known disporoside A (4). The structures of the new compounds were elucidated mainly by extensive spectroscopic analysis (1D and 2D NMR, FABMS, and HRESIMS). Compounds 1, 2, and 4 demonstrated weak antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata, and C.tropicalis, with MIC values between 12.5 and 50 microg/mL.