31 research outputs found
Exposure to the agricultural fungicide tebuconazole promotes Aspergillus fumigatus cross-resistance to clinical azoles. [Comini S. is the co-first author; Banche G. is the corresponding author; Cuffini A.M. is the co-corresponding author]
No full textResistance to clinical triazoles in Aspergillus fumigatus is a growing concern for individuals at high risk of Aspergillus infection. Two triazole resistance selection routes are currently being investigated: one occurring in triazole-treated patients in healthcare settings, and the second taking place in the environment due to the widespread use of agricultural triazoles. This study aimed to assess the ability of agricultural azoles to promote cross-resistance to clinical azoles in A. fumigatus. Five A. fumigatus isolates susceptible to clinical azoles were exposed to the triazole 14α-demethylase inhibitor, tebuconazole (TBC), and then antifungal susceptibility tests for voriconazole, itraconazole, posaconazole and isavuconazole were performed. Under TBC selection pressure, all A. fumigatus isolates exhibited resistance to clinical triazoles. However, only two displayed a multiresistant phenotype to clinical azoles. TBC exposure was also associated with delayed conidia formation and progressive absence of conidiation. Noteworthy, no TBC-exposed clones harbored TR34/L98H mutation, as judged by real-time PCR assays. The observation that TBC exposure promotes cross-resistance to clinical triazoles warrants careful and thorough assessment of the human health risk associated with agricultural azoles. The absence of TR34/L98H mutation in cross-resistant A. fumigatus isolates suggests that other cyp51A mutations may be involved in clinical azole cross-resistance
Antimicrobial oxygen-loaded nanobubbles as promising tools to promote wound healing in hypoxic human keratinocytes [*N. Mandras is the corresponding author, **A.M. Cuffini and M. Prato are co-last authors]
No full text: Chronic wounds (CWs) are typically characterized by persistent hypoxia, exacerbated inflammation, and impaired skin tissue remodeling. Additionally, CWs are often worsened by microbial infections. Oxygen-loaded nanobubbles (OLNBs), displaying a peculiar structure based on oxygen-solving perfluorocarbons such as perfluoropentane in the inner core and polysaccharydes including chitosan in the outer shell, have proven effective in delivering oxygen to hypoxic tissues. Antimicrobial properties have been largely reported for chitosan. In the present work chitosan/perfluoropentane OLNBs were challenged for biocompatibility with human skin cells and ability to promote wound healing processes, as well as for their antimicrobial properties against methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. After cellular internalization, OLNBs were not toxic to human keratinocytes (HaCaT), whereas oxygen-free NBs (OFNBs) slightly affected their viability. Hypoxia-dependent inhibition of keratinocyte migratory ability after scratch was fully reversed by OLNBs, but not OFNBs. Both OLNBs and OFNBs exerted chitosan-induced short-term bacteriostatic activity against MRSA (up to 6 h) and long-term fungistatic activity against C. albicans (up to 24 h). Short-term antibacterial activity associated with NB prolonged adhesion to MRSA cell wall (up to 24 h) while long-term antifungal activity followed NB early internalization by C. albicans (already after 3 h of incubation). Taken altogether, these data support chitosan-shelled and perfluoropentane-cored OLNB potential as innovative, promising, non-toxic, and cost-effective antimicrobial devices promoting repair processes to be used for treatment of MRSA- and C. albicans-infected CWs
Evaluation of the Antifungal Activity of Mentha x piperita (Lamiaceae) of Pancalieri (Turin, Italy) Essential Oil and Its Synergistic Interaction with Azoles [V.Tullio is the Corresponding and the First Author, N.Mandras is the Last Author]
No full textThe promising antimicrobial activity of essential oils (EOs) has led researchers to use them in combination with antimicrobial drugs in order to reduce drug toxicity, side effects, and resistance to single agents. Mentha x piperita, known worldwide as “Mentha of Pancalieri”, is produced locally at Pancalieri (Turin, Italy). The EO from this Mentha species is considered as one of the best mint EOs in the world. In our research, we assessed the antifungal activity of “Mentha of Pancalieri” EO, either alone or in combination with azole drugs (fluconazole, itraconazole, ketoconazole) against a wide panel of yeast and dermatophyte clinical isolates. The EO was analyzed by GC-MS, and its antifungal properties were evaluated by minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) parameters, in accordance with the CLSI guidelines, with some modifications. The interaction of EO with azoles was evaluated through the chequerboard and isobologram methods. The results suggest that this EO exerts a fungicidal activity against yeasts and a fungistatic activity against dermatophytes. Interaction studies with azoles indicated mainly synergistic profiles between itraconazole and EO vs. Candida spp., Cryptococcus neoformans, and Trichophyton mentagrophytes. Thus, the “Mentha of Pancalieri” EO may act as a potential antifungal agent and could serve as a natural adjuvant for fungal infection treatment
Antifungal Activity of Melaleuca alternifolia Essential Oil (TTO) and Its Synergy with Itraconazole or Ketoconazole against Trichophyton rubrum [*V.Tullio is the last author and the corresponding author]
No full textAntibacterial and Antifungal Efficacy of Medium and Low Weight Chitosan-Shelled Nanodroplets for the Treatment of Infected Chronic Wounds [* V. Allizond is the corresponding author; **A.M. Cuffini and G. Banche are co-last authors]
No full textPurpose: Medium versus low weight (MW vs LW) chitosan-shelled oxygen-loaded nanodroplets (cOLNDs) and oxygen-free nanodroplets (cOFNDs) were comparatively challenged for biocompatibility on human keratinocytes, for antimicrobial activity against four common infectious agents of chronic wounds (CWs) - methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pyogenes, Candida albicans and C. glabrata - and for their physical interaction with cell walls/membranes. Methods: cNDs were characterized for morphology and physico-chemical properties by microscopy and dynamic light scattering. In vitro oxygen release from cOLNDs was measured through an oximeter. ND biocompatibility and ability to promote wound healing in human normoxic/hypoxic skin cells were challenged by LDH and MTT assays using keratinocytes. ND antimicrobial activity was investigated by monitoring upon incubation with/without MW or LW cOLNDs/cOFNDs either bacteria or yeast growth over time. The mechanical interaction between NDs and microorganisms was also assessed by confocal microscopy. Results: LW cNDs appeared less toxic to keratinocytes than MW cNDs. Based on cell counts, either MW or LW cOLNDs and cOFNDs displayed long-term antimicrobial efficacy against S. pyogenes, C. albicans, and C. glabrata (up to 24 h), whereas a short-term cytostatic effects against MRSA (up to 6 h) was revealed. The internalization of all ND formulations by all four microorganisms, already after 3 h of incubation, was showed, with the only exception to MW cOLNDs/cOFNDs that adhered to MRSA walls without being internalized even after 24 h. Conclusion: cNDs exerted bacteriostatic and fungistatic effects, due to the presence of chitosan in the outer shell and independently of oxygen addition in the inner core. The duration of such effects strictly depends on the characteristics of each microbial species, and not on the molecular weight of chitosan in ND shells. However, LW chitosan was better tolerated by human keratinocytes than MW. For these reasons, the use of LW NDs should be recommended in future research to assess cOLND efficacy for the treatment of infected CWs
Antimicrobial efficacy of cryotreatment against Enterococcus faecalis in root canals [*G.Banche is the corresponding author]
No full textNew Generation of Osteoinductive and Antimicrobial Polycaprolactone-Based Scaffolds in Bone Tissue Engineering: A Review (Banche G and Longo F are the corresponding authors; Allizond V is the last author)
No full textA case of fluconazole, voriconazole-resistant Cryptococcus neoformans isolated from an immunocompetent patient [*V.Tullio is the corresponding author]
No full textAntibacterial efficacy and drug-induced tooth discolouration of antibiotic combinations for endodontic regenerative procedures [*V.Allizond is the corresponding author]
No full textImmunomodulating effect of antimicrobial agents on cytokine production by human polymorphonuclear neutrophils [*A.M. Cuffini is the corresponding author]
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