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1.
Braz J Microbiol ; 55(1): 143-154, 2024 Mar.
Article En | MEDLINE | ID: mdl-37964169

Farnesol is a natural essential oil with antimicrobial properties. Complexation of farnesol in chitosan nanoparticles can be useful to improve its bioavailability and potentiate its antifungal capabilities such as inhibition of hyphal and biofilm formation. The aim of this study was to develop and characterize chitosan nanoparticles with farnesol (NF) and evaluate their toxicity and antifungal action on C. albicans in vivo. The NF were prepared by the ionic gelation method and showed physicochemical characteristics such as diameter less than 200 nm, monodisperse distribution, positive zeta potential, spherical morphology, and stability after 120 days of storage. In the evaluation of toxicity in Galleria mellonella, NF did not reduce the survival rate, indicating that there was no toxicity in vivo at the doses tested. In the assays with G. mellonella infected by C. albicans, the larvae treated with NF had a high survival rate after 48 h, with a significant reduction of the fungal load and inhibition of the formation of biofilms and hyphae. In the murine model of vulvovaginal candidiasis (VVC), histopathological analysis showed a reduction in inflammatory parameters, fungal burden, and hyphal inhibition in mice treated with NF. The produced nanoparticles can be a promising alternative to inhibit C. albicans infection.


Chitosan , Nanoparticles , Animals , Mice , Candida albicans , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Farnesol/pharmacology , Chitosan/pharmacology , Biofilms , Nanoparticles/chemistry
2.
Med Mycol ; 61(11)2023 Nov 06.
Article En | MEDLINE | ID: mdl-37947253

Vulvovaginal candidiasis (VVC) is a fungal infection caused mainly by Candida albicans. The treatment of VVC with azoles has been impaired due to the increased cases of resistance presented by this pathogen. The aim of the present study was to investigate the antifungal activity of mucoadhesive chitosan nanoparticles encapsulating both green propolis and fluconazole for topical use in the treatment of VVC. The nanoparticles were prepared by the ionic gelation method, resulting in a size of 316.5 nm containing 22 mg/kg of green propolis and 2.4 mg/kg of fluconazole. The nanoparticles were non-toxic in vitro using red blood cells or in vivo in a Galleria mellonella toxicity model. The treatment of female BALB/c mice infected by C. albicans ATCC 10231 with topical nanoparticles co-encapsulating fluconazole and green propolis was effective even using a fluconazole amount 20 times lower than the amount of miconazole nitrate 2% cream. Considering that the mucoadhesive property of chitosan, which is known to allow a prolonged retention time of the compounds at the mucous epithelia, the antifungal potential of the phenols and flavonoids present in green propolis may have favored the effectiveness of this treatment. These results indicate that this formulation of topical use for fluconazole associated with green propolis can be used as a promising approach to therapy for the treatment of VVC, thus contributing to reducing the development of resistance to azoles.


Vulvovaginal candidiasis is a fungal infection for which we search for alternatives for its treatment. Thus, a nanoparticle formulation based on fluconazole and green propolis was developed. These nanoparticles were tested, and we obtained adequate results in laboratory tests.


Candidiasis, Vulvovaginal , Chitosan , Nanoparticles , Propolis , Female , Animals , Mice , Fluconazole/therapeutic use , Candidiasis, Vulvovaginal/drug therapy , Candidiasis, Vulvovaginal/microbiology , Candidiasis, Vulvovaginal/veterinary , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Propolis/therapeutic use , Disease Models, Animal , Candida albicans , Microbial Sensitivity Tests/veterinary
3.
Med Mycol ; 59(10): 958-969, 2021 Oct 04.
Article En | MEDLINE | ID: mdl-33877362

Biofilms are important virulence factor in infections caused by microorganisms because of its complex structure, which provide resistance to conventional antimicrobials. Strategies involving the use of molecules capable of inhibiting their formation and also act synergistically with conventional drugs have been explored. Farnesol is a molecule present in essential oils and produced by Candida albicans as a quorum sensing component. This sesquiterpene presents inhibitory properties in the formation of microbial biofilms and synergism with antimicrobials used in clinical practice, and can be exploited even for eradication of biofilms formed by drug-resistant microorganisms. Despite this, farnesol has physical and chemical characteristics that can limit its use, such as high hydrophobicity and volatility. Therefore, nanotechnology may represent an option to improve the efficiency of this molecule in high complex environments such as biofilms. Nanostructured systems present important results in the improvement of treatment with different commercial drugs and molecules with therapeutic or preventive potential. The formation of nanoparticles offers advantages such as protection of the incorporated drugs against degradation, improved biodistribution and residence time in specific treatment sites. The combination of farnesol with nanotechnology may be promising for the development of more effective antibiofilm therapies, as it can improve its solubility, reduce volatility, and increase bioavailability. This review summarizes existing data about farnesol, its action on biofilms, and discusses its encapsulation in nanostructured systems. LAY SUMMARY: Farnesol is a natural compound that inhibits the formation of biofilms from different microbial species. The encapsulation of this molecule in nanoparticles is a promising alternative for the development of more effective therapies against biofilms.


Biofilms , Farnesol , Animals , Candida albicans , Farnesol/pharmacology , Nanotechnology , Tissue Distribution
4.
Braz J Microbiol ; 51(4): 1465-1473, 2020 Dec.
Article En | MEDLINE | ID: mdl-32638273

Vulvovaginal candidiasis is a serious health problem affecting numerous women around the world. Its treatment is based on antifungals which may not provide an effective cure because of the resistance presented by its etiological pathogens Candida spp. Candida albicans is the most prevalent species related to vulvovaginal candidiasis. Here, we evaluated the in vivo antifungal potential of thiosemicarbazide and thiosemicarbazide encapsulated within chitosan nanoparticles in a murine model of vulvovaginal candidiasis. The results demonstrated the antifungal capacity of free or nanoencapsulated thiosemicarbazide within chitosan to reduce the fungal load in the vaginal tissue of infected mice. In addition, histological analyses indicated the absence or a mild to moderate infection in thiosemicarbazide-treated groups. Statistical tests confirmed the existence of significant differences between the treated and the control groups. Therefore, our results suggest a potential application of thiosemicarbazide and encapsulated thiosemicarbazide as an alternative vulvovaginal candidiasis therapy.


Antifungal Agents , Candidiasis, Vulvovaginal/drug therapy , Semicarbazides , Animals , Antifungal Agents/administration & dosage , Antifungal Agents/pharmacology , Candida albicans/drug effects , Chitosan , Drug Evaluation, Preclinical , Female , Mice , Mice, Inbred BALB C , Nanoparticles , Semicarbazides/administration & dosage , Semicarbazides/pharmacology , Vagina/microbiology
5.
Rev Soc Bras Med Trop ; 52: e20180267, 2019 Apr 11.
Article En | MEDLINE | ID: mdl-30994801

INTRODUCTION: The prevalence of hematogenous dissemination of mycobacteria is high in immunosuppressed patients. The isolation of mycobacteria in culture remains the standard procedure. METHODS: This is a cross-sectional study based on the results of solid (Löwenstein-Jensen medium) and semi-automated liquid (BACTEC 9240) blood cultures, obtained from the Lacen-GO database. RESULTS: The implementation of a semi-automated procedure resulted in an increase of 61.5% and 350.0% in the positive results for Mycobacterium tuberculosis complex and nontuberculous mycobacteria, respectively. This technique also accelerated the detection of positive results. CONCLUSIONS: Semi-automated liquid blood culture showed a better performance in the diagnosis of mycobacteremia.


Automation, Laboratory/methods , Bacteriological Techniques/methods , Mycobacterium/isolation & purification , Cross-Sectional Studies , Culture Media , Humans , Reagent Kits, Diagnostic , Sensitivity and Specificity , Time Factors
6.
Rev. Soc. Bras. Med. Trop ; 52: e20180267, 2019. graf
Article En | LILACS | ID: biblio-1041521

Abstract INTRODUCTION The prevalence of hematogenous dissemination of mycobacteria is high in immunosuppressed patients. The isolation of mycobacteria in culture remains the standard procedure. METHODS This is a cross-sectional study based on the results of solid (Löwenstein-Jensen medium) and semi-automated liquid (BACTEC 9240) blood cultures, obtained from the Lacen-GO database. RESULTS The implementation of a semi-automated procedure resulted in an increase of 61.5% and 350.0% in the positive results for Mycobacterium tuberculosis complex and nontuberculous mycobacteria, respectively. This technique also accelerated the detection of positive results. CONCLUSIONS Semi-automated liquid blood culture showed a better performance in the diagnosis of mycobacteremia.


Humans , Bacteriological Techniques/methods , Automation, Laboratory/methods , Mycobacterium/isolation & purification , Reagent Kits, Diagnostic , Time Factors , Cross-Sectional Studies , Sensitivity and Specificity , Culture Media
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